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@martinradev martinradev commented Jun 4, 2020

Hello people,

I recently disclosed a small issue of making the KASLR offsets the same and known between reboots of the VM. This happens in two steps:

  1. disabling RDRAND for the VM
  2. modifying the TSC for the guest via interception or setting the tsc ratio msr to 0.

This patch fixes the issue by making RDRAND a required feature for starting a SEV-ES and -SNP VM. I tested locally that booting the VM fails if RDRAND is not supported.

Let me know of your thoughts on the fix and whether you have any other concerns.

This patch offers a hardening to prevent the HV from 'disabling'
KASLR for the VM. With this patch any intercepted cpuid would fail
if RDRAND is not offered and already cause a fault in the Linux boot
stage.

Without RDRAND, KASLR and the initial sequence of kernel stack
canaries rely on the TSC for randomness. The HV is able to
specify a fixed TSC value by either intercepting RDTSC or specifying

a zero multiplier with the TSC_RATIO MSR.
Adding such a requirement should not cause any harm for when
SEV-ES or SEV-SNP are enabled because in such cases RDRAND should
also be supported.

Signed-off-by: Martin Radev <martin.b.radev@gmail.com>
@martinradev martinradev changed the base branch from master to sev-es-5.6-v3 June 4, 2020 13:35
tlendacky pushed a commit that referenced this pull request Jun 24, 2020
Here is the steps to reproduce the problem:
ip netns add foo
ip netns add bar
ip -n foo link add xfrmi0 type xfrm dev lo if_id 42
ip -n foo link set xfrmi0 netns bar
ip netns del foo
ip netns del bar

Which results to:
[  186.686395] general protection fault, probably for non-canonical address 0x6b6b6b6b6b6b6bd3: 0000 [#1] SMP PTI
[  186.687665] CPU: 7 PID: 232 Comm: kworker/u16:2 Not tainted 5.6.0+ #1
[  186.688430] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014
[  186.689420] Workqueue: netns cleanup_net
[  186.689903] RIP: 0010:xfrmi_dev_uninit+0x1b/0x4b [xfrm_interface]
[  186.690657] Code: 44 f6 ff ff 31 c0 5b 5d 41 5c 41 5d 41 5e c3 48 8d 8f c0 08 00 00 8b 05 ce 14 00 00 48 8b 97 d0 08 00 00 48 8b 92 c0 0e 00 00 <48> 8b 14 c2 48 8b 02 48 85 c0 74 19 48 39 c1 75 0c 48 8b 87 c0 08
[  186.692838] RSP: 0018:ffffc900003b7d68 EFLAGS: 00010286
[  186.693435] RAX: 000000000000000d RBX: ffff8881b0f31000 RCX: ffff8881b0f318c0
[  186.694334] RDX: 6b6b6b6b6b6b6b6b RSI: 0000000000000246 RDI: ffff8881b0f31000
[  186.695190] RBP: ffffc900003b7df0 R08: ffff888236c07740 R09: 0000000000000040
[  186.696024] R10: ffffffff81fce1b8 R11: 0000000000000002 R12: ffffc900003b7d80
[  186.696859] R13: ffff8881edcc6a40 R14: ffff8881a1b6e780 R15: ffffffff81ed47c8
[  186.697738] FS:  0000000000000000(0000) GS:ffff888237dc0000(0000) knlGS:0000000000000000
[  186.698705] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  186.699408] CR2: 00007f2129e93148 CR3: 0000000001e0a000 CR4: 00000000000006e0
[  186.700221] Call Trace:
[  186.700508]  rollback_registered_many+0x32b/0x3fd
[  186.701058]  ? __rtnl_unlock+0x20/0x3d
[  186.701494]  ? arch_local_irq_save+0x11/0x17
[  186.702012]  unregister_netdevice_many+0x12/0x55
[  186.702594]  default_device_exit_batch+0x12b/0x150
[  186.703160]  ? prepare_to_wait_exclusive+0x60/0x60
[  186.703719]  cleanup_net+0x17d/0x234
[  186.704138]  process_one_work+0x196/0x2e8
[  186.704652]  worker_thread+0x1a4/0x249
[  186.705087]  ? cancel_delayed_work+0x92/0x92
[  186.705620]  kthread+0x105/0x10f
[  186.706000]  ? __kthread_bind_mask+0x57/0x57
[  186.706501]  ret_from_fork+0x35/0x40
[  186.706978] Modules linked in: xfrm_interface nfsv3 nfs_acl auth_rpcgss nfsv4 nfs lockd grace fscache sunrpc button parport_pc parport serio_raw evdev pcspkr loop ext4 crc16 mbcache jbd2 crc32c_generic 8139too ide_cd_mod cdrom ide_gd_mod ata_generic ata_piix libata scsi_mod piix psmouse i2c_piix4 ide_core 8139cp i2c_core mii floppy
[  186.710423] ---[ end trace 463bba18105537e5 ]---

The problem is that x-netns xfrm interface are not removed when the link
netns is removed. This causes later this oops when thoses interfaces are
removed.

Let's add a handler to remove all interfaces related to a netns when this
netns is removed.

Fixes: f203b76 ("xfrm: Add virtual xfrm interfaces")
Reported-by: Christophe Gouault <christophe.gouault@6wind.com>
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
tlendacky pushed a commit that referenced this pull request Jun 24, 2020
Commit ed83038 ("scsi: ibmvfc: Avoid loss of all paths during SVC node
reboot") introduced a regression where when the client resets or re-enables
its CRQ with the hypervisor there is a chance that if the server side
doesn't issue its INIT handshake quick enough the client can issue an
Implicit Logout prior to doing an NPIV Login. The server treats this
scenario as a protocol violation and closes the CRQ on its end forcing the
client through a reset that gets the client host state and next host action
out of agreement leading to a BUG assert.

ibmvfc 30000003: Partner initialization complete
ibmvfc 30000002: Partner initialization complete
ibmvfc 30000002: Host partner adapter deregistered or failed (rc=2)
ibmvfc 30000002: Partner initialized
------------[ cut here ]------------
kernel BUG at ../drivers/scsi/ibmvscsi/ibmvfc.c:4489!
Oops: Exception in kernel mode, sig: 5 [#1]
LE PAGE_SIZE=64K MMU=Hash SMP NR_CPUS=2048 NUMA pSeries
Supported: No, Unreleased kernel
CPU: 16 PID: 1290 Comm: ibmvfc_0 Tainted: G           OE  X   5.3.18-12-default
NIP:  c00800000d84a2b4 LR: c00800000d84a040 CTR: c00800000d84a2a0
REGS: c00000000cb57a00 TRAP: 0700   Tainted: G           OE  X    (5.3.18-12-default)
MSR:  800000000282b033 <SF,VEC,VSX,EE,FP,ME,IR,DR,RI,LE>  CR: 24000848  XER: 00000001
CFAR: c00800000d84a070 IRQMASK: 1
GPR00: c00800000d84a040 c00000000cb57c90 c00800000d858e00 0000000000000000
GPR04: 0000000000000000 0000000000000000 0000000000000000 00000000000000a0
GPR08: c00800000d84a074 0000000000000001 0000000000000014 c00800000d84d7d0
GPR12: 0000000000000000 c00000001ea28200 c00000000016cd98 0000000000000000
GPR16: c00800000d84b7b8 0000000000000000 0000000000000000 c00000542c706d68
GPR20: 0000000000000005 c00000542c706d88 5deadbeef0000100 5deadbeef0000122
GPR24: 000000000000000c 000000000000000b c00800000d852180 0000000000000001
GPR28: 0000000000000000 c00000542c706da0 c00000542c706860 c00000542c706828
NIP [c00800000d84a2b4] ibmvfc_work+0x3ac/0xc90 [ibmvfc]
LR [c00800000d84a040] ibmvfc_work+0x138/0xc90 [ibmvfc]

This scenario can be prevented by rejecting any attempt to send an Implicit
Logout if the client adapter is not logged in yet.

Link: https://lore.kernel.org/r/20200427214824.6890-1-tyreld@linux.ibm.com
Fixes: ed83038 ("scsi: ibmvfc: Avoid loss of all paths during SVC node reboot")
Signed-off-by: Brian King <brking@linux.vnet.ibm.com>
Signed-off-by: Tyrel Datwyler <tyreld@linux.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
tlendacky pushed a commit that referenced this pull request Jun 24, 2020
Commit 64e90a8 ("Introduce STATIC_USERMODEHELPER to mediate
call_usermodehelper()") added the optiont to disable all
call_usermodehelper() calls by setting STATIC_USERMODEHELPER_PATH to
an empty string. When this is done, and crashdump is triggered, it
will crash on null pointer dereference, since we make assumptions
over what call_usermodehelper_exec() did.

This has been reported by Sergey when one triggers a a coredump
with the following configuration:

```
CONFIG_STATIC_USERMODEHELPER=y
CONFIG_STATIC_USERMODEHELPER_PATH=""
kernel.core_pattern = |/usr/lib/systemd/systemd-coredump %P %u %g %s %t %c %h %e
```

The way disabling the umh was designed was that call_usermodehelper_exec()
would just return early, without an error. But coredump assumes
certain variables are set up for us when this happens, and calls
ile_start_write(cprm.file) with a NULL file.

[    2.819676] BUG: kernel NULL pointer dereference, address: 0000000000000020
[    2.819859] #PF: supervisor read access in kernel mode
[    2.820035] #PF: error_code(0x0000) - not-present page
[    2.820188] PGD 0 P4D 0
[    2.820305] Oops: 0000 [#1] SMP PTI
[    2.820436] CPU: 2 PID: 89 Comm: a Not tainted 5.7.0-rc1+ torvalds#7
[    2.820680] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS ?-20190711_202441-buildvm-armv7-10.arm.fedoraproject.org-2.fc31 04/01/2014
[    2.821150] RIP: 0010:do_coredump+0xd80/0x1060
[    2.821385] Code: e8 95 11 ed ff 48 c7 c6 cc a7 b4 81 48 8d bd 28 ff
ff ff 89 c2 e8 70 f1 ff ff 41 89 c2 85 c0 0f 84 72 f7 ff ff e9 b4 fe ff
ff <48> 8b 57 20 0f b7 02 66 25 00 f0 66 3d 00 8
0 0f 84 9c 01 00 00 44
[    2.822014] RSP: 0000:ffffc9000029bcb8 EFLAGS: 00010246
[    2.822339] RAX: 0000000000000000 RBX: ffff88803f860000 RCX: 000000000000000a
[    2.822746] RDX: 0000000000000009 RSI: 0000000000000282 RDI: 0000000000000000
[    2.823141] RBP: ffffc9000029bde8 R08: 0000000000000000 R09: ffffc9000029bc00
[    2.823508] R10: 0000000000000001 R11: ffff88803dec90be R12: ffffffff81c39da0
[    2.823902] R13: ffff88803de84400 R14: 0000000000000000 R15: 0000000000000000
[    2.824285] FS:  00007fee08183540(0000) GS:ffff88803e480000(0000) knlGS:0000000000000000
[    2.824767] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[    2.825111] CR2: 0000000000000020 CR3: 000000003f856005 CR4: 0000000000060ea0
[    2.825479] Call Trace:
[    2.825790]  get_signal+0x11e/0x720
[    2.826087]  do_signal+0x1d/0x670
[    2.826361]  ? force_sig_info_to_task+0xc1/0xf0
[    2.826691]  ? force_sig_fault+0x3c/0x40
[    2.826996]  ? do_trap+0xc9/0x100
[    2.827179]  exit_to_usermode_loop+0x49/0x90
[    2.827359]  prepare_exit_to_usermode+0x77/0xb0
[    2.827559]  ? invalid_op+0xa/0x30
[    2.827747]  ret_from_intr+0x20/0x20
[    2.827921] RIP: 0033:0x55e2c76d2129
[    2.828107] Code: 2d ff ff ff e8 68 ff ff ff 5d c6 05 18 2f 00 00 01
c3 0f 1f 80 00 00 00 00 c3 0f 1f 80 00 00 00 00 e9 7b ff ff ff 55 48 89
e5 <0f> 0b b8 00 00 00 00 5d c3 66 2e 0f 1f 84 0
0 00 00 00 00 0f 1f 40
[    2.828603] RSP: 002b:00007fffeba5e080 EFLAGS: 00010246
[    2.828801] RAX: 000055e2c76d2125 RBX: 0000000000000000 RCX: 00007fee0817c718
[    2.829034] RDX: 00007fffeba5e188 RSI: 00007fffeba5e178 RDI: 0000000000000001
[    2.829257] RBP: 00007fffeba5e080 R08: 0000000000000000 R09: 00007fee08193c00
[    2.829482] R10: 0000000000000009 R11: 0000000000000000 R12: 000055e2c76d2040
[    2.829727] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
[    2.829964] CR2: 0000000000000020
[    2.830149] ---[ end trace ceed83d8c68a1bf1 ]---
```

Cc: <stable@vger.kernel.org> # v4.11+
Fixes: 64e90a8 ("Introduce STATIC_USERMODEHELPER to mediate call_usermodehelper()")
BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=199795
Reported-by: Tony Vroon <chainsaw@gentoo.org>
Reported-by: Sergey Kvachonok <ravenexp@gmail.com>
Tested-by: Sergei Trofimovich <slyfox@gentoo.org>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
Link: https://lore.kernel.org/r/20200416162859.26518-1-mcgrof@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
tlendacky pushed a commit that referenced this pull request Jun 24, 2020
netvsc_start_xmit is used as a callback function for the ndo_start_xmit
function pointer. ndo_start_xmit's return type is netdev_tx_t but
netvsc_start_xmit's return type is int.

This causes a failure with Control Flow Integrity (CFI), which requires
function pointer prototypes and callback function definitions to match
exactly. When CFI is in enforcing, the kernel panics. When booting a
CFI kernel with WSL 2, the VM is immediately terminated because of this.

The splat when CONFIG_CFI_PERMISSIVE is used:

[    5.916765] CFI failure (target: netvsc_start_xmit+0x0/0x10):
[    5.916771] WARNING: CPU: 8 PID: 0 at kernel/cfi.c:29 __cfi_check_fail+0x2e/0x40
[    5.916772] Modules linked in:
[    5.916774] CPU: 8 PID: 0 Comm: swapper/8 Not tainted 5.7.0-rc3-next-20200424-microsoft-cbl-00001-ged4eb37d2c69-dirty #1
[    5.916776] RIP: 0010:__cfi_check_fail+0x2e/0x40
[    5.916777] Code: 48 c7 c7 70 98 63 a9 48 c7 c6 11 db 47 a9 e8 69 55 59 00 85 c0 75 02 5b c3 48 c7 c7 73 c6 43 a9 48 89 de 31 c0 e8 12 2d f0 ff <0f> 0b 5b c3 00 00 cc cc 00 00 cc cc 00 00 cc cc 00 00 85 f6 74 25
[    5.916778] RSP: 0018:ffffa803c0260b78 EFLAGS: 00010246
[    5.916779] RAX: 712a1af25779e900 RBX: ffffffffa8cf7950 RCX: ffffffffa962cf08
[    5.916779] RDX: ffffffffa9c36b60 RSI: 0000000000000082 RDI: ffffffffa9c36b5c
[    5.916780] RBP: ffff8ffc4779c2c0 R08: 0000000000000001 R09: ffffffffa9c3c300
[    5.916781] R10: 0000000000000151 R11: ffffffffa9c36b60 R12: ffff8ffe39084000
[    5.916782] R13: ffffffffa8cf7950 R14: ffffffffa8d12cb0 R15: ffff8ffe39320140
[    5.916784] FS:  0000000000000000(0000) GS:ffff8ffe3bc00000(0000) knlGS:0000000000000000
[    5.916785] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[    5.916786] CR2: 00007ffef5749408 CR3: 00000002f4f5e000 CR4: 0000000000340ea0
[    5.916787] Call Trace:
[    5.916788]  <IRQ>
[    5.916790]  __cfi_check+0x3ab58/0x450e0
[    5.916793]  ? dev_hard_start_xmit+0x11f/0x160
[    5.916795]  ? sch_direct_xmit+0xf2/0x230
[    5.916796]  ? __dev_queue_xmit.llvm.11471227737707190958+0x69d/0x8e0
[    5.916797]  ? neigh_resolve_output+0xdf/0x220
[    5.916799]  ? neigh_connected_output.cfi_jt+0x8/0x8
[    5.916801]  ? ip6_finish_output2+0x398/0x4c0
[    5.916803]  ? nf_nat_ipv6_out+0x10/0xa0
[    5.916804]  ? nf_hook_slow+0x84/0x100
[    5.916807]  ? ip6_input_finish+0x8/0x8
[    5.916807]  ? ip6_output+0x6f/0x110
[    5.916808]  ? __ip6_local_out.cfi_jt+0x8/0x8
[    5.916810]  ? mld_sendpack+0x28e/0x330
[    5.916811]  ? ip_rt_bug+0x8/0x8
[    5.916813]  ? mld_ifc_timer_expire+0x2db/0x400
[    5.916814]  ? neigh_proxy_process+0x8/0x8
[    5.916816]  ? call_timer_fn+0x3d/0xd0
[    5.916817]  ? __run_timers+0x2a9/0x300
[    5.916819]  ? rcu_core_si+0x8/0x8
[    5.916820]  ? run_timer_softirq+0x14/0x30
[    5.916821]  ? __do_softirq+0x154/0x262
[    5.916822]  ? native_x2apic_icr_write+0x8/0x8
[    5.916824]  ? irq_exit+0xba/0xc0
[    5.916825]  ? hv_stimer0_vector_handler+0x99/0xe0
[    5.916826]  ? hv_stimer0_callback_vector+0xf/0x20
[    5.916826]  </IRQ>
[    5.916828]  ? hv_stimer_global_cleanup.cfi_jt+0x8/0x8
[    5.916829]  ? raw_setsockopt+0x8/0x8
[    5.916830]  ? default_idle+0xe/0x10
[    5.916832]  ? do_idle.llvm.10446269078108580492+0xb7/0x130
[    5.916833]  ? raw_setsockopt+0x8/0x8
[    5.916833]  ? cpu_startup_entry+0x15/0x20
[    5.916835]  ? cpu_hotplug_enable.cfi_jt+0x8/0x8
[    5.916836]  ? start_secondary+0x188/0x190
[    5.916837]  ? secondary_startup_64+0xa5/0xb0
[    5.916838] ---[ end trace f2683fa869597ba5 ]---

Avoid this by using the right return type for netvsc_start_xmit.

Fixes: fceaf24 ("Staging: hv: add the Hyper-V virtual network driver")
Link: ClangBuiltLinux#1009
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Reviewed-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
tlendacky pushed a commit that referenced this pull request Jun 24, 2020
…kernel/git/kvmarm/kvmarm into kvm-master

KVM/arm fixes for Linux 5.7, take #1

- Prevent the userspace API from interacting directly with the HW
  stage of the virtual GIC
- Fix a couple of vGIC memory leaks
- Tighten the rules around the use of the 32bit PSCI functions
  for 64bit guest, as well as the opposite situation (matches the
  specification)
tlendacky pushed a commit that referenced this pull request Jun 24, 2020
Commit f458d03 ("kvm: ioapic: Lazy update IOAPIC EOI") introduces
the following infinite loop:

BUG: stack guard page was hit at 000000008f595917 \
(stack is 00000000bdefe5a4..00000000ae2b06f5)
kernel stack overflow (double-fault): 0000 [#1] SMP NOPTI
RIP: 0010:kvm_set_irq+0x51/0x160 [kvm]
Call Trace:
 irqfd_resampler_ack+0x32/0x90 [kvm]
 kvm_notify_acked_irq+0x62/0xd0 [kvm]
 kvm_ioapic_update_eoi_one.isra.0+0x30/0x120 [kvm]
 ioapic_set_irq+0x20e/0x240 [kvm]
 kvm_ioapic_set_irq+0x5c/0x80 [kvm]
 kvm_set_irq+0xbb/0x160 [kvm]
 ? kvm_hv_set_sint+0x20/0x20 [kvm]
 irqfd_resampler_ack+0x32/0x90 [kvm]
 kvm_notify_acked_irq+0x62/0xd0 [kvm]
 kvm_ioapic_update_eoi_one.isra.0+0x30/0x120 [kvm]
 ioapic_set_irq+0x20e/0x240 [kvm]
 kvm_ioapic_set_irq+0x5c/0x80 [kvm]
 kvm_set_irq+0xbb/0x160 [kvm]
 ? kvm_hv_set_sint+0x20/0x20 [kvm]
....

The re-entrancy happens because the irq state is the OR of
the interrupt state and the resamplefd state.  That is, we don't
want to show the state as 0 until we've had a chance to set the
resamplefd.  But if the interrupt has _not_ gone low then
ioapic_set_irq is invoked again, causing an infinite loop.

This can only happen for a level-triggered interrupt, otherwise
irqfd_inject would immediately set the KVM_USERSPACE_IRQ_SOURCE_ID high
and then low.  Fortunately, in the case of level-triggered interrupts the VMEXIT already happens because
TMR is set.  Thus, fix the bug by restricting the lazy invocation
of the ack notifier to edge-triggered interrupts, the only ones that
need it.

Tested-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Reported-by: borisvk@bstnet.org
Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Link: https://www.spinics.net/lists/kvm/msg213512.html
Fixes: f458d03 ("kvm: ioapic: Lazy update IOAPIC EOI")
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=207489
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
tlendacky pushed a commit that referenced this pull request Jun 24, 2020
Once the intel_context is closed, the GEM context may be freed and so
the link from intel_context.gem_context is invalid.

<3>[  219.782944] BUG: KASAN: use-after-free in intel_engine_coredump_alloc+0x1bc3/0x2250 [i915]
<3>[  219.782996] Read of size 8 at addr ffff8881d7dff0b8 by task kworker/0:1/12

<4>[  219.783052] CPU: 0 PID: 12 Comm: kworker/0:1 Tainted: G     U            5.7.0-rc2-g1f3ffd7683d54-kasan_118+ #1
<4>[  219.783055] Hardware name: System manufacturer System Product Name/Z170 PRO GAMING, BIOS 3402 04/26/2017
<4>[  219.783105] Workqueue: events heartbeat [i915]
<4>[  219.783109] Call Trace:
<4>[  219.783113]  <IRQ>
<4>[  219.783119]  dump_stack+0x96/0xdb
<4>[  219.783177]  ? intel_engine_coredump_alloc+0x1bc3/0x2250 [i915]
<4>[  219.783182]  print_address_description.constprop.6+0x16/0x310
<4>[  219.783239]  ? intel_engine_coredump_alloc+0x1bc3/0x2250 [i915]
<4>[  219.783295]  ? intel_engine_coredump_alloc+0x1bc3/0x2250 [i915]
<4>[  219.783300]  __kasan_report+0x137/0x190
<4>[  219.783359]  ? intel_engine_coredump_alloc+0x1bc3/0x2250 [i915]
<4>[  219.783366]  kasan_report+0x32/0x50
<4>[  219.783426]  intel_engine_coredump_alloc+0x1bc3/0x2250 [i915]
<4>[  219.783481]  execlists_reset+0x39c/0x13d0 [i915]
<4>[  219.783494]  ? mark_held_locks+0x9e/0xe0
<4>[  219.783546]  ? execlists_hold+0xfc0/0xfc0 [i915]
<4>[  219.783551]  ? lockdep_hardirqs_on+0x348/0x5f0
<4>[  219.783557]  ? _raw_spin_unlock_irqrestore+0x34/0x60
<4>[  219.783606]  ? execlists_submission_tasklet+0x118/0x3a0 [i915]
<4>[  219.783615]  tasklet_action_common.isra.14+0x13b/0x410
<4>[  219.783623]  ? __do_softirq+0x1e4/0x9a7
<4>[  219.783630]  __do_softirq+0x226/0x9a7
<4>[  219.783643]  do_softirq_own_stack+0x2a/0x40
<4>[  219.783647]  </IRQ>
<4>[  219.783692]  ? heartbeat+0x3e2/0x10f0 [i915]
<4>[  219.783696]  do_softirq.part.13+0x49/0x50
<4>[  219.783700]  __local_bh_enable_ip+0x1a2/0x1e0
<4>[  219.783748]  heartbeat+0x409/0x10f0 [i915]
<4>[  219.783801]  ? __live_idle_pulse+0x9f0/0x9f0 [i915]
<4>[  219.783806]  ? lock_acquire+0x1ac/0x8a0
<4>[  219.783811]  ? process_one_work+0x811/0x1870
<4>[  219.783827]  ? rcu_read_lock_sched_held+0x9c/0xd0
<4>[  219.783832]  ? rcu_read_lock_bh_held+0xb0/0xb0
<4>[  219.783836]  ? _raw_spin_unlock_irq+0x1f/0x40
<4>[  219.783845]  process_one_work+0x8ca/0x1870
<4>[  219.783848]  ? lock_acquire+0x1ac/0x8a0
<4>[  219.783852]  ? worker_thread+0x1d0/0xb80
<4>[  219.783864]  ? pwq_dec_nr_in_flight+0x2c0/0x2c0
<4>[  219.783870]  ? do_raw_spin_lock+0x129/0x290
<4>[  219.783886]  worker_thread+0x82/0xb80
<4>[  219.783895]  ? __kthread_parkme+0xaf/0x1b0
<4>[  219.783902]  ? process_one_work+0x1870/0x1870
<4>[  219.783906]  kthread+0x34e/0x420
<4>[  219.783911]  ? kthread_create_on_node+0xc0/0xc0
<4>[  219.783918]  ret_from_fork+0x3a/0x50

<3>[  219.783950] Allocated by task 1264:
<4>[  219.783975]  save_stack+0x19/0x40
<4>[  219.783978]  __kasan_kmalloc.constprop.3+0xa0/0xd0
<4>[  219.784029]  i915_gem_create_context+0xa2/0xab8 [i915]
<4>[  219.784081]  i915_gem_context_create_ioctl+0x1fa/0x450 [i915]
<4>[  219.784085]  drm_ioctl_kernel+0x1d8/0x270
<4>[  219.784088]  drm_ioctl+0x676/0x930
<4>[  219.784092]  ksys_ioctl+0xb7/0xe0
<4>[  219.784096]  __x64_sys_ioctl+0x6a/0xb0
<4>[  219.784100]  do_syscall_64+0x94/0x530
<4>[  219.784103]  entry_SYSCALL_64_after_hwframe+0x49/0xb3

<3>[  219.784120] Freed by task 12:
<4>[  219.784141]  save_stack+0x19/0x40
<4>[  219.784145]  __kasan_slab_free+0x130/0x180
<4>[  219.784148]  kmem_cache_free_bulk+0x1bd/0x500
<4>[  219.784152]  kfree_rcu_work+0x1d8/0x890
<4>[  219.784155]  process_one_work+0x8ca/0x1870
<4>[  219.784158]  worker_thread+0x82/0xb80
<4>[  219.784162]  kthread+0x34e/0x420
<4>[  219.784165]  ret_from_fork+0x3a/0x50

Fixes: 2e46a2a ("drm/i915: Use explicit flag to mark unreachable intel_context")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Acked-by: Akeem G Abodunrin <akeem.g.abodunrin@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200428090255.10035-1-chris@chris-wilson.co.uk
(cherry picked from commit 24aac33)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
tlendacky pushed a commit that referenced this pull request Jun 24, 2020
…ay_plane

Since moving the obj->vma.list to a spin_lock, and the vm->bound_list to
its vm->mutex, along with tracking shrinkable status under its own
spinlock, we no long require the object to be locked by the caller.

This is fortunate as it appears we can be called with the lock along an
error path in flipping:

<4> [139.942851] WARN_ON(debug_locks && !lock_is_held(&(&((obj)->base.resv)->lock.base)->dep_map))
<4> [139.943242] WARNING: CPU: 0 PID: 1203 at drivers/gpu/drm/i915/gem/i915_gem_domain.c:405 i915_gem_object_unpin_from_display_plane+0x70/0x130 [i915]
<4> [139.943263] Modules linked in: snd_hda_intel i915 vgem snd_hda_codec_realtek snd_hda_codec_generic coretemp snd_intel_dspcfg snd_hda_codec snd_hwdep snd_hda_core r8169 lpc_ich snd_pcm realtek prime_numbers [last unloaded: i915]
<4> [139.943347] CPU: 0 PID: 1203 Comm: kms_flip Tainted: G     U            5.6.0-gd0fda5c2cf3f1-drmtip_474+ #1
<4> [139.943363] Hardware name:  /D510MO, BIOS MOPNV10J.86A.0311.2010.0802.2346 08/02/2010
<4> [139.943589] RIP: 0010:i915_gem_object_unpin_from_display_plane+0x70/0x130 [i915]
<4> [139.943589] Code: 85 28 01 00 00 be ff ff ff ff 48 8d 78 60 e8 d7 9b f0 e2 85 c0 75 b9 48 c7 c6 50 b9 38 c0 48 c7 c7 e9 48 3c c0 e8 20 d4 e9 e2 <0f> 0b eb a2 48 c7 c1 08 bb 38 c0 ba 0a 01 00 00 48 c7 c6 88 a3 35
<4> [139.943589] RSP: 0018:ffffb774c0603b48 EFLAGS: 00010282
<4> [139.943589] RAX: 0000000000000000 RBX: ffff9a142fa36e80 RCX: 0000000000000006
<4> [139.943589] RDX: 000000000000160d RSI: ffff9a142c1a88f8 RDI: ffffffffa434a64d
<4> [139.943589] RBP: ffff9a1410a513c0 R08: ffff9a142c1a88f8 R09: 0000000000000000
<4> [139.943589] R10: 0000000000000000 R11: 0000000000000000 R12: ffff9a1436ee94b8
<4> [139.943589] R13: 0000000000000001 R14: 00000000ffffffff R15: ffff9a1410960000
<4> [139.943589] FS:  00007fc73a744e40(0000) GS:ffff9a143da00000(0000) knlGS:0000000000000000
<4> [139.943589] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
<4> [139.943589] CR2: 00007fc73997e098 CR3: 000000002f5fe000 CR4: 00000000000006f0
<4> [139.943589] Call Trace:
<4> [139.943589]  intel_pin_and_fence_fb_obj+0x1c9/0x1f0 [i915]
<4> [139.943589]  intel_plane_pin_fb+0x3f/0xd0 [i915]
<4> [139.943589]  intel_prepare_plane_fb+0x13b/0x5c0 [i915]
<4> [139.943589]  drm_atomic_helper_prepare_planes+0x85/0x110
<4> [139.943589]  intel_atomic_commit+0xda/0x390 [i915]
<4> [139.943589]  drm_atomic_helper_page_flip+0x9c/0xd0
<4> [139.943589]  ? drm_event_reserve_init+0x46/0x60
<4> [139.943589]  drm_mode_page_flip_ioctl+0x587/0x5d0

This completes the symmetry lost in commit 8b1c78e ("drm/i915: Avoid
calling i915_gem_object_unbind holding object lock").

Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/1743
Fixes: 8b1c78e ("drm/i915: Avoid calling i915_gem_object_unbind holding object lock")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Matthew Auld <matthew.auld@intel.com>
Cc: Andi Shyti <andi.shyti@intel.com>
Cc: <stable@vger.kernel.org> # v5.6+
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200420125356.26614-1-chris@chris-wilson.co.uk
(cherry picked from commit a95f3ac)
(cherry picked from commit 2208b85fa1766ee4821a9435d548578b67090531)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
tlendacky pushed a commit that referenced this pull request Jun 24, 2020
This patch fixes the following warning and few other instances of
traversal of evm_config_xattrnames list:

[   32.848432] =============================
[   32.848707] WARNING: suspicious RCU usage
[   32.848966] 5.7.0-rc1-00006-ga8d5875ce5f0b #1 Not tainted
[   32.849308] -----------------------------
[   32.849567] security/integrity/evm/evm_main.c:231 RCU-list traversed in non-reader section!!

Since entries are only added to the list and never deleted, use
list_for_each_entry_lockless() instead of list_for_each_entry_rcu for
traversing the list.  Also, add a relevant comment in evm_secfs.c to
indicate this fact.

Reported-by: kernel test robot <lkp@intel.com>
Suggested-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Madhuparna Bhowmik <madhuparnabhowmik10@gmail.com>
Acked-by: Paul E. McKenney <paulmck@kernel.org> (RCU viewpoint)
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
tlendacky pushed a commit that referenced this pull request Jun 24, 2020
Since 5.7-rc1, on btrfs we have a percpu counter initialization for
which we always pass a GFP_KERNEL gfp_t argument (this happens since
commit 2992df7 ("btrfs: Implement DREW lock")).

That is safe in some contextes but not on others where allowing fs
reclaim could lead to a deadlock because we are either holding some
btrfs lock needed for a transaction commit or holding a btrfs
transaction handle open.  Because of that we surround the call to the
function that initializes the percpu counter with a NOFS context using
memalloc_nofs_save() (this is done at btrfs_init_fs_root()).

However it turns out that this is not enough to prevent a possible
deadlock because percpu_alloc() determines if it is in an atomic context
by looking exclusively at the gfp flags passed to it (GFP_KERNEL in this
case) and it is not aware that a NOFS context is set.

Because percpu_alloc() thinks it is in a non atomic context it locks the
pcpu_alloc_mutex.  This can result in a btrfs deadlock when
pcpu_balance_workfn() is running, has acquired that mutex and is waiting
for reclaim, while the btrfs task that called percpu_counter_init() (and
therefore percpu_alloc()) is holding either the btrfs commit_root
semaphore or a transaction handle (done fs/btrfs/backref.c:
iterate_extent_inodes()), which prevents reclaim from finishing as an
attempt to commit the current btrfs transaction will deadlock.

Lockdep reports this issue with the following trace:

  ======================================================
  WARNING: possible circular locking dependency detected
  5.6.0-rc7-btrfs-next-77 #1 Not tainted
  ------------------------------------------------------
  kswapd0/91 is trying to acquire lock:
  ffff8938a3b3fdc8 (&delayed_node->mutex){+.+.}, at: __btrfs_release_delayed_node.part.0+0x3f/0x320 [btrfs]

  but task is already holding lock:
  ffffffffb4f0dbc0 (fs_reclaim){+.+.}, at: __fs_reclaim_acquire+0x5/0x30

  which lock already depends on the new lock.

  the existing dependency chain (in reverse order) is:

  -> #4 (fs_reclaim){+.+.}:
         fs_reclaim_acquire.part.0+0x25/0x30
         __kmalloc+0x5f/0x3a0
         pcpu_create_chunk+0x19/0x230
         pcpu_balance_workfn+0x56a/0x680
         process_one_work+0x235/0x5f0
         worker_thread+0x50/0x3b0
         kthread+0x120/0x140
         ret_from_fork+0x3a/0x50

  -> #3 (pcpu_alloc_mutex){+.+.}:
         __mutex_lock+0xa9/0xaf0
         pcpu_alloc+0x480/0x7c0
         __percpu_counter_init+0x50/0xd0
         btrfs_drew_lock_init+0x22/0x70 [btrfs]
         btrfs_get_fs_root+0x29c/0x5c0 [btrfs]
         resolve_indirect_refs+0x120/0xa30 [btrfs]
         find_parent_nodes+0x50b/0xf30 [btrfs]
         btrfs_find_all_leafs+0x60/0xb0 [btrfs]
         iterate_extent_inodes+0x139/0x2f0 [btrfs]
         iterate_inodes_from_logical+0xa1/0xe0 [btrfs]
         btrfs_ioctl_logical_to_ino+0xb4/0x190 [btrfs]
         btrfs_ioctl+0x165a/0x3130 [btrfs]
         ksys_ioctl+0x87/0xc0
         __x64_sys_ioctl+0x16/0x20
         do_syscall_64+0x5c/0x260
         entry_SYSCALL_64_after_hwframe+0x49/0xbe

  -> #2 (&fs_info->commit_root_sem){++++}:
         down_write+0x38/0x70
         btrfs_cache_block_group+0x2ec/0x500 [btrfs]
         find_free_extent+0xc6a/0x1600 [btrfs]
         btrfs_reserve_extent+0x9b/0x180 [btrfs]
         btrfs_alloc_tree_block+0xc1/0x350 [btrfs]
         alloc_tree_block_no_bg_flush+0x4a/0x60 [btrfs]
         __btrfs_cow_block+0x122/0x5a0 [btrfs]
         btrfs_cow_block+0x106/0x240 [btrfs]
         commit_cowonly_roots+0x55/0x310 [btrfs]
         btrfs_commit_transaction+0x509/0xb20 [btrfs]
         sync_filesystem+0x74/0x90
         generic_shutdown_super+0x22/0x100
         kill_anon_super+0x14/0x30
         btrfs_kill_super+0x12/0x20 [btrfs]
         deactivate_locked_super+0x31/0x70
         cleanup_mnt+0x100/0x160
         task_work_run+0x93/0xc0
         exit_to_usermode_loop+0xf9/0x100
         do_syscall_64+0x20d/0x260
         entry_SYSCALL_64_after_hwframe+0x49/0xbe

  -> #1 (&space_info->groups_sem){++++}:
         down_read+0x3c/0x140
         find_free_extent+0xef6/0x1600 [btrfs]
         btrfs_reserve_extent+0x9b/0x180 [btrfs]
         btrfs_alloc_tree_block+0xc1/0x350 [btrfs]
         alloc_tree_block_no_bg_flush+0x4a/0x60 [btrfs]
         __btrfs_cow_block+0x122/0x5a0 [btrfs]
         btrfs_cow_block+0x106/0x240 [btrfs]
         btrfs_search_slot+0x50c/0xd60 [btrfs]
         btrfs_lookup_inode+0x3a/0xc0 [btrfs]
         __btrfs_update_delayed_inode+0x90/0x280 [btrfs]
         __btrfs_commit_inode_delayed_items+0x81f/0x870 [btrfs]
         __btrfs_run_delayed_items+0x8e/0x180 [btrfs]
         btrfs_commit_transaction+0x31b/0xb20 [btrfs]
         iterate_supers+0x87/0xf0
         ksys_sync+0x60/0xb0
         __ia32_sys_sync+0xa/0x10
         do_syscall_64+0x5c/0x260
         entry_SYSCALL_64_after_hwframe+0x49/0xbe

  -> #0 (&delayed_node->mutex){+.+.}:
         __lock_acquire+0xef0/0x1c80
         lock_acquire+0xa2/0x1d0
         __mutex_lock+0xa9/0xaf0
         __btrfs_release_delayed_node.part.0+0x3f/0x320 [btrfs]
         btrfs_evict_inode+0x40d/0x560 [btrfs]
         evict+0xd9/0x1c0
         dispose_list+0x48/0x70
         prune_icache_sb+0x54/0x80
         super_cache_scan+0x124/0x1a0
         do_shrink_slab+0x176/0x440
         shrink_slab+0x23a/0x2c0
         shrink_node+0x188/0x6e0
         balance_pgdat+0x31d/0x7f0
         kswapd+0x238/0x550
         kthread+0x120/0x140
         ret_from_fork+0x3a/0x50

  other info that might help us debug this:

  Chain exists of:
    &delayed_node->mutex --> pcpu_alloc_mutex --> fs_reclaim

   Possible unsafe locking scenario:

         CPU0                    CPU1
         ----                    ----
    lock(fs_reclaim);
                                 lock(pcpu_alloc_mutex);
                                 lock(fs_reclaim);
    lock(&delayed_node->mutex);

   *** DEADLOCK ***

  3 locks held by kswapd0/91:
   #0: (fs_reclaim){+.+.}, at: __fs_reclaim_acquire+0x5/0x30
   #1: (shrinker_rwsem){++++}, at: shrink_slab+0x12f/0x2c0
   #2: (&type->s_umount_key#43){++++}, at: trylock_super+0x16/0x50

  stack backtrace:
  CPU: 1 PID: 91 Comm: kswapd0 Not tainted 5.6.0-rc7-btrfs-next-77 #1
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.0-0-ga698c8995f-prebuilt.qemu.org 04/01/2014
  Call Trace:
   dump_stack+0x8f/0xd0
   check_noncircular+0x170/0x190
   __lock_acquire+0xef0/0x1c80
   lock_acquire+0xa2/0x1d0
   __mutex_lock+0xa9/0xaf0
   __btrfs_release_delayed_node.part.0+0x3f/0x320 [btrfs]
   btrfs_evict_inode+0x40d/0x560 [btrfs]
   evict+0xd9/0x1c0
   dispose_list+0x48/0x70
   prune_icache_sb+0x54/0x80
   super_cache_scan+0x124/0x1a0
   do_shrink_slab+0x176/0x440
   shrink_slab+0x23a/0x2c0
   shrink_node+0x188/0x6e0
   balance_pgdat+0x31d/0x7f0
   kswapd+0x238/0x550
   kthread+0x120/0x140
   ret_from_fork+0x3a/0x50

This could be fixed by making btrfs pass GFP_NOFS instead of GFP_KERNEL
to percpu_counter_init() in contextes where it is not reclaim safe,
however that type of approach is discouraged since
memalloc_[nofs|noio]_save() were introduced.  Therefore this change
makes pcpu_alloc() look up into an existing nofs/noio context before
deciding whether it is in an atomic context or not.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: Dennis Zhou <dennis@kernel.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Christoph Lameter <cl@linux.com>
Link: http://lkml.kernel.org/r/20200430164356.15543-1-fdmanana@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
tlendacky pushed a commit that referenced this pull request Jun 24, 2020
And there are no multiple TRBs on EP0 and WA1 workaround,
so it doesn't need to change TRB for EP0. It fixes below oops.

configfs-gadget gadget: high-speed config #1: b
android_work: sent uevent USB_STATE=CONFIGURED
Unable to handle kernel read from unreadable memory at virtual address 0000000000000008
Mem abort info:
android_work: sent uevent USB_STATE=DISCONNECTED
  ESR = 0x96000004
  EC = 0x25: DABT (current EL), IL = 32 bits

  SET = 0, FnV = 0
  EA = 0, S1PTW = 0
Data abort info:
  ISV = 0, ISS = 0x00000004
  CM = 0, WnR = 0
user pgtable: 4k pages, 48-bit VAs, pgdp=00000008b5bb7000
[0000000000000008] pgd=0000000000000000
Internal error: Oops: 96000004 [#1] PREEMPT SMP
Modules linked in:
CPU: 2 PID: 430 Comm: HwBinder:401_1 Not tainted 5.4.24-06071-g6fa8921409c1-dirty torvalds#77
Hardware name: Freescale i.MX8QXP MEK (DT)
pstate: 60400085 (nZCv daIf +PAN -UAO)
pc : cdns3_gadget_ep_dequeue+0x1d4/0x270
lr : cdns3_gadget_ep_dequeue+0x48/0x270
sp : ffff800012763ba0
x29: ffff800012763ba0 x28: ffff00082c653c00
x27: 0000000000000000 x26: ffff000068fa7b00
x25: ffff0000699b2000 x24: ffff00082c6ac000
x23: ffff000834f0a480 x22: ffff000834e87b9c
x21: 0000000000000000 x20: ffff000834e87800
x19: ffff000069eddc00 x18: 0000000000000000
x17: 0000000000000000 x16: 0000000000000000
x15: 0000000000000000 x14: 0000000000000000
x13: 0000000000000000 x12: 0000000000000001
x11: ffff80001180fbe8 x10: 0000000000000001
x9 : ffff800012101558 x8 : 0000000000000001
x7 : 0000000000000006 x6 : ffff000835d9c668
x5 : ffff000834f0a4c8 x4 : 0000000096000000
x3 : 0000000000001810 x2 : 0000000000000000
x1 : ffff800024bd001c x0 : 0000000000000001
Call trace:
 cdns3_gadget_ep_dequeue+0x1d4/0x270
 usb_ep_dequeue+0x34/0xf8
 composite_dev_cleanup+0x154/0x170
 configfs_composite_unbind+0x6c/0xa8
 usb_gadget_remove_driver+0x44/0x70
 usb_gadget_unregister_driver+0x74/0xe0
 unregister_gadget+0x28/0x58
 gadget_dev_desc_UDC_store+0x80/0x110
 configfs_write_file+0x1e0/0x2a0
 __vfs_write+0x48/0x90
 vfs_write+0xe4/0x1c8
 ksys_write+0x78/0x100
 __arm64_sys_write+0x24/0x30
 el0_svc_common.constprop.0+0x74/0x168
 el0_svc_handler+0x34/0xa0
 el0_svc+0x8/0xc
Code: 52830203 b9407660 f94042e4 11000400 (b9400841)
---[ end trace 1574516e4c1772ca ]---
Kernel panic - not syncing: Fatal exception
SMP: stopping secondary CPUs
Kernel Offset: disabled
CPU features: 0x0002,20002008
Memory Limit: none
Rebooting in 5 seconds..

Fixes: f616c3b ("usb: cdns3: Fix dequeue implementation")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Peter Chen <peter.chen@nxp.com>
Signed-off-by: Felipe Balbi <balbi@kernel.org>
tlendacky pushed a commit that referenced this pull request Jun 24, 2020
…em boot up

Booting one of my machines, it triggered the following crash:

 Kernel/User page tables isolation: enabled
 ftrace: allocating 36577 entries in 143 pages
 Starting tracer 'function'
 BUG: unable to handle page fault for address: ffffffffa000005c
 #PF: supervisor write access in kernel mode
 #PF: error_code(0x0003) - permissions violation
 PGD 2014067 P4D 2014067 PUD 2015063 PMD 7b253067 PTE 7b25206
 Oops: 0003 [#1] PREEMPT SMP PTI
 CPU: 0 PID: 0 Comm: swapper Not tainted 5.4.0-test+ torvalds#24
 Hardware name: To Be Filled By O.E.M. To Be Filled By O.E.M./To be filled by O.E.M., BIOS SDBLI944.86P 05/08/2007
 RIP: 0010:text_poke_early+0x4a/0x58
 Code: 34 24 48 89 54 24 08 e8 bf 72 0b 00 48 8b 34 24 48 8b 4c 24 08 84 c0 74 0b 48 89 df f3 a4 48 83 c4 10 5b c3 9c 58 fa 48 89 df <f3> a4 50 9d 48 83 c4 10 5b e9 d6 f9 ff ff
0 41 57 49
 RSP: 0000:ffffffff82003d38 EFLAGS: 00010046
 RAX: 0000000000000046 RBX: ffffffffa000005c RCX: 0000000000000005
 RDX: 0000000000000005 RSI: ffffffff825b9a90 RDI: ffffffffa000005c
 RBP: ffffffffa000005c R08: 0000000000000000 R09: ffffffff8206e6e0
 R10: ffff88807b01f4c0 R11: ffffffff8176c106 R12: ffffffff8206e6e0
 R13: ffffffff824f2440 R14: 0000000000000000 R15: ffffffff8206eac0
 FS:  0000000000000000(0000) GS:ffff88807d400000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: ffffffffa000005c CR3: 0000000002012000 CR4: 00000000000006b0
 Call Trace:
  text_poke_bp+0x27/0x64
  ? mutex_lock+0x36/0x5d
  arch_ftrace_update_trampoline+0x287/0x2d5
  ? ftrace_replace_code+0x14b/0x160
  ? ftrace_update_ftrace_func+0x65/0x6c
  __register_ftrace_function+0x6d/0x81
  ftrace_startup+0x23/0xc1
  register_ftrace_function+0x20/0x37
  func_set_flag+0x59/0x77
  __set_tracer_option.isra.19+0x20/0x3e
  trace_set_options+0xd6/0x13e
  apply_trace_boot_options+0x44/0x6d
  register_tracer+0x19e/0x1ac
  early_trace_init+0x21b/0x2c9
  start_kernel+0x241/0x518
  ? load_ucode_intel_bsp+0x21/0x52
  secondary_startup_64+0xa4/0xb0

I was able to trigger it on other machines, when I added to the kernel
command line of both "ftrace=function" and "trace_options=func_stack_trace".

The cause is the "ftrace=function" would register the function tracer
and create a trampoline, and it will set it as executable and
read-only. Then the "trace_options=func_stack_trace" would then update
the same trampoline to include the stack tracer version of the function
tracer. But since the trampoline already exists, it updates it with
text_poke_bp(). The problem is that text_poke_bp() called while
system_state == SYSTEM_BOOTING, it will simply do a memcpy() and not
the page mapping, as it would think that the text is still read-write.
But in this case it is not, and we take a fault and crash.

Instead, lets keep the ftrace trampolines read-write during boot up,
and then when the kernel executable text is set to read-only, the
ftrace trampolines get set to read-only as well.

Link: https://lkml.kernel.org/r/20200430202147.4dc6e2de@oasis.local.home

Cc: Ingo Molnar <mingo@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: stable@vger.kernel.org
Fixes: 768ae44 ("x86/ftrace: Use text_poke()")
Acked-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
tlendacky pushed a commit that referenced this pull request Jun 24, 2020
…sg list

On platforms with IOMMU enabled, multiple SGs can be coalesced into one
by the IOMMU driver. In that case the SG list processing as part of the
completion of a urb on a bulk endpoint can result into a NULL pointer
dereference with the below stack dump.

<6> Unable to handle kernel NULL pointer dereference at virtual address 0000000c
<6> pgd = c0004000
<6> [0000000c] *pgd=00000000
<6> Internal error: Oops: 5 [#1] PREEMPT SMP ARM
<2> PC is at xhci_queue_bulk_tx+0x454/0x80c
<2> LR is at xhci_queue_bulk_tx+0x44c/0x80c
<2> pc : [<c08907c4>]    lr : [<c08907bc>]    psr: 000000d3
<2> sp : ca337c80  ip : 00000000  fp : ffffffff
<2> r10: 00000000  r9 : 50037000  r8 : 00004000
<2> r7 : 00000000  r6 : 00004000  r5 : 00000000  r4 : 00000000
<2> r3 : 00000000  r2 : 00000082  r1 : c2c1a200  r0 : 00000000
<2> Flags: nzcv  IRQs off  FIQs off  Mode SVC_32  ISA ARM  Segment none
<2> Control: 10c0383d  Table: b412c06a  DAC: 00000051
<6> Process usb-storage (pid: 5961, stack limit = 0xca336210)
<snip>
<2> [<c08907c4>] (xhci_queue_bulk_tx)
<2> [<c0881b3c>] (xhci_urb_enqueue)
<2> [<c0831068>] (usb_hcd_submit_urb)
<2> [<c08350b4>] (usb_sg_wait)
<2> [<c089f384>] (usb_stor_bulk_transfer_sglist)
<2> [<c089f2c0>] (usb_stor_bulk_srb)
<2> [<c089fe38>] (usb_stor_Bulk_transport)
<2> [<c089f468>] (usb_stor_invoke_transport)
<2> [<c08a11b4>] (usb_stor_control_thread)
<2> [<c014a534>] (kthread)

The above NULL pointer dereference is the result of block_len and the
sent_len set to zero after the first SG of the list when IOMMU driver
is enabled. Because of this the loop of processing the SGs has run
more than num_sgs which resulted in a sg_next on the last SG of the
list which has SG_END set.

Fix this by check for the sg before any attributes of the sg are
accessed.

[modified reason for null pointer dereference in commit message subject -Mathias]
Fixes: f9c589e ("xhci: TD-fragment, align the unsplittable case with a bounce buffer")
Cc: stable@vger.kernel.org
Signed-off-by: Sriharsha Allenki <sallenki@codeaurora.org>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20200514110432.25564-2-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
tlendacky pushed a commit that referenced this pull request Jun 24, 2020
While removing the host (e.g. for USB role switch from host to device),
if runtime pm is enabled by user, below oops occurs on dwc3 and cdns3
platforms.
Keeping the xhci-plat device active during host removal, and disabling
runtime pm before calling pm_runtime_set_suspended() fixes them.

oops1:
Unable to handle kernel NULL pointer dereference at virtual address
0000000000000240
Internal error: Oops: 96000004 [#1] PREEMPT SMP
Modules linked in:
CPU: 0 PID: 5 Comm: kworker/0:0 Not tainted 5.4.3-00107-g64d454a-dirty
Hardware name: FSL i.MX8MP EVK (DT)
Workqueue: pm pm_runtime_work
pstate: 60000005 (nZCv daif -PAN -UAO)
pc : xhci_suspend+0x34/0x698
lr : xhci_plat_runtime_suspend+0x2c/0x38
sp : ffff800011ddbbc0
Call trace:
 xhci_suspend+0x34/0x698
 xhci_plat_runtime_suspend+0x2c/0x38
 pm_generic_runtime_suspend+0x28/0x40
 __rpm_callback+0xd8/0x138
 rpm_callback+0x24/0x98
 rpm_suspend+0xe0/0x448
 rpm_idle+0x124/0x140
 pm_runtime_work+0xa0/0xf8
 process_one_work+0x1dc/0x370
 worker_thread+0x48/0x468
 kthread+0xf0/0x120
 ret_from_fork+0x10/0x1c

oops2:
usb 2-1: USB disconnect, device number 2
xhci-hcd xhci-hcd.1.auto: remove, state 4
usb usb2: USB disconnect, device number 1
xhci-hcd xhci-hcd.1.auto: USB bus 2 deregistered
xhci-hcd xhci-hcd.1.auto: remove, state 4
usb usb1: USB disconnect, device number 1
Unable to handle kernel NULL pointer dereference at virtual address
0000000000000138
Internal error: Oops: 96000004 [#1] PREEMPT SMP
Modules linked in:
CPU: 2 PID: 7 Comm: kworker/u8:0 Not tainted 5.6.0-rc4-next-20200304-03578
Hardware name: Freescale i.MX8QXP MEK (DT)
Workqueue: 1-0050 tcpm_state_machine_work
pstate: 20000005 (nzCv daif -PAN -UAO)
pc : xhci_free_dev+0x214/0x270
lr : xhci_plat_runtime_resume+0x78/0x88
sp : ffff80001006b5b0
Call trace:
 xhci_free_dev+0x214/0x270
 xhci_plat_runtime_resume+0x78/0x88
 pm_generic_runtime_resume+0x30/0x48
 __rpm_callback+0x90/0x148
 rpm_callback+0x28/0x88
 rpm_resume+0x568/0x758
 rpm_resume+0x260/0x758
 rpm_resume+0x260/0x758
 __pm_runtime_resume+0x40/0x88
 device_release_driver_internal+0xa0/0x1c8
 device_release_driver+0x1c/0x28
 bus_remove_device+0xd4/0x158
 device_del+0x15c/0x3a0
 usb_disable_device+0xb0/0x268
 usb_disconnect+0xcc/0x300
 usb_remove_hcd+0xf4/0x1dc
 xhci_plat_remove+0x78/0xe0
 platform_drv_remove+0x30/0x50
 device_release_driver_internal+0xfc/0x1c8
 device_release_driver+0x1c/0x28
 bus_remove_device+0xd4/0x158
 device_del+0x15c/0x3a0
 platform_device_del.part.0+0x20/0x90
 platform_device_unregister+0x28/0x40
 cdns3_host_exit+0x20/0x40
 cdns3_role_stop+0x60/0x90
 cdns3_role_set+0x64/0xd8
 usb_role_switch_set_role.part.0+0x3c/0x68
 usb_role_switch_set_role+0x20/0x30
 tcpm_mux_set+0x60/0xf8
 tcpm_reset_port+0xa4/0xf0
 tcpm_detach.part.0+0x28/0x50
 tcpm_state_machine_work+0x12ac/0x2360
 process_one_work+0x1c8/0x470
 worker_thread+0x50/0x428
 kthread+0xfc/0x128
 ret_from_fork+0x10/0x18
Code: c8037c02 35ffffa3 17ffe7c3 f9800011 (c85f7c01)
---[ end trace 45b1a173d2679e44 ]---

[minor commit message cleanup  -Mathias]
Cc: Baolin Wang <baolin.wang@linaro.org>
Cc: <stable@vger.kernel.org>
Fixes: b0c69b4 ("usb: host: plat: Enable xHCI plat runtime PM")
Reviewed-by: Peter Chen <peter.chen@nxp.com>
Tested-by: Peter Chen <peter.chen@nxp.com>
Signed-off-by: Li Jun <jun.li@nxp.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20200514110432.25564-3-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
tlendacky pushed a commit that referenced this pull request Jun 24, 2020
security_secid_to_secctx is called by the bpf_lsm hook and a successful
return value (i.e 0) implies that the parameter will be consumed by the
LSM framework. The current behaviour return success when the pointer
isn't initialized when CONFIG_BPF_LSM is enabled, with the default
return from kernel/bpf/bpf_lsm.c.

This is the internal error:

[ 1229.341488][ T2659] usercopy: Kernel memory exposure attempt detected from null address (offset 0, size 280)!
[ 1229.374977][ T2659] ------------[ cut here ]------------
[ 1229.376813][ T2659] kernel BUG at mm/usercopy.c:99!
[ 1229.378398][ T2659] Internal error: Oops - BUG: 0 [#1] PREEMPT SMP
[ 1229.380348][ T2659] Modules linked in:
[ 1229.381654][ T2659] CPU: 0 PID: 2659 Comm: systemd-journal Tainted: G    B   W         5.7.0-rc5-next-20200511-00019-g864e0c6319b8-dirty torvalds#13
[ 1229.385429][ T2659] Hardware name: linux,dummy-virt (DT)
[ 1229.387143][ T2659] pstate: 80400005 (Nzcv daif +PAN -UAO BTYPE=--)
[ 1229.389165][ T2659] pc : usercopy_abort+0xc8/0xcc
[ 1229.390705][ T2659] lr : usercopy_abort+0xc8/0xcc
[ 1229.392225][ T2659] sp : ffff000064247450
[ 1229.393533][ T2659] x29: ffff000064247460 x28: 0000000000000000
[ 1229.395449][ T2659] x27: 0000000000000118 x26: 0000000000000000
[ 1229.397384][ T2659] x25: ffffa000127049e0 x24: ffffa000127049e0
[ 1229.399306][ T2659] x23: ffffa000127048e0 x22: ffffa000127048a0
[ 1229.401241][ T2659] x21: ffffa00012704b80 x20: ffffa000127049e0
[ 1229.403163][ T2659] x19: ffffa00012704820 x18: 0000000000000000
[ 1229.405094][ T2659] x17: 0000000000000000 x16: 0000000000000000
[ 1229.407008][ T2659] x15: 0000000000000000 x14: 003d090000000000
[ 1229.408942][ T2659] x13: ffff80000d5b25b2 x12: 1fffe0000d5b25b1
[ 1229.410859][ T2659] x11: 1fffe0000d5b25b1 x10: ffff80000d5b25b1
[ 1229.412791][ T2659] x9 : ffffa0001034bee0 x8 : ffff00006ad92d8f
[ 1229.414707][ T2659] x7 : 0000000000000000 x6 : ffffa00015eacb20
[ 1229.416642][ T2659] x5 : ffff0000693c8040 x4 : 0000000000000000
[ 1229.418558][ T2659] x3 : ffffa0001034befc x2 : d57a7483a01c6300
[ 1229.420610][ T2659] x1 : 0000000000000000 x0 : 0000000000000059
[ 1229.422526][ T2659] Call trace:
[ 1229.423631][ T2659]  usercopy_abort+0xc8/0xcc
[ 1229.425091][ T2659]  __check_object_size+0xdc/0x7d4
[ 1229.426729][ T2659]  put_cmsg+0xa30/0xa90
[ 1229.428132][ T2659]  unix_dgram_recvmsg+0x80c/0x930
[ 1229.429731][ T2659]  sock_recvmsg+0x9c/0xc0
[ 1229.431123][ T2659]  ____sys_recvmsg+0x1cc/0x5f8
[ 1229.432663][ T2659]  ___sys_recvmsg+0x100/0x160
[ 1229.434151][ T2659]  __sys_recvmsg+0x110/0x1a8
[ 1229.435623][ T2659]  __arm64_sys_recvmsg+0x58/0x70
[ 1229.437218][ T2659]  el0_svc_common.constprop.1+0x29c/0x340
[ 1229.438994][ T2659]  do_el0_svc+0xe8/0x108
[ 1229.440587][ T2659]  el0_svc+0x74/0x88
[ 1229.441917][ T2659]  el0_sync_handler+0xe4/0x8b4
[ 1229.443464][ T2659]  el0_sync+0x17c/0x180
[ 1229.444920][ T2659] Code: aa1703e2 aa1603e1 910a8260 97ecc860 (d4210000)
[ 1229.447070][ T2659] ---[ end trace 400497d91baeaf51 ]---
[ 1229.448791][ T2659] Kernel panic - not syncing: Fatal exception
[ 1229.450692][ T2659] Kernel Offset: disabled
[ 1229.452061][ T2659] CPU features: 0x240002,20002004
[ 1229.453647][ T2659] Memory Limit: none
[ 1229.455015][ T2659] ---[ end Kernel panic - not syncing: Fatal exception ]---

Rework the so the default return value is -EOPNOTSUPP.

There are likely other callbacks such as security_inode_getsecctx() that
may have the same problem, and that someone that understand the code
better needs to audit them.

Thank you Arnd for helping me figure out what went wrong.

Fixes: 98e828a ("security: Refactor declaration of LSM hooks")
Signed-off-by: Anders Roxell <anders.roxell@linaro.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: James Morris <jamorris@linux.microsoft.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/bpf/20200512174607.9630-1-anders.roxell@linaro.org
tlendacky pushed a commit that referenced this pull request Jun 24, 2020
FuzzUSB (a variant of syzkaller) found an illegal array access
using an incorrect index while binding a gadget with UDC.

Reference: https://www.spinics.net/lists/linux-usb/msg194331.html

This bug occurs when a size variable used for a buffer
is misused to access its strcpy-ed buffer.
Given a buffer along with its size variable (taken from user input),
from which, a new buffer is created using kstrdup().
Due to the original buffer containing 0 value in the middle,
the size of the kstrdup-ed buffer becomes smaller than that of the original.
So accessing the kstrdup-ed buffer with the same size variable
triggers memory access violation.

The fix makes sure no zero value in the buffer,
by comparing the strlen() of the orignal buffer with the size variable,
so that the access to the kstrdup-ed buffer is safe.

BUG: KASAN: slab-out-of-bounds in gadget_dev_desc_UDC_store+0x1ba/0x200
drivers/usb/gadget/configfs.c:266
Read of size 1 at addr ffff88806a55dd7e by task syz-executor.0/17208

CPU: 2 PID: 17208 Comm: syz-executor.0 Not tainted 5.6.8 #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0xce/0x128 lib/dump_stack.c:118
 print_address_description.constprop.4+0x21/0x3c0 mm/kasan/report.c:374
 __kasan_report+0x131/0x1b0 mm/kasan/report.c:506
 kasan_report+0x12/0x20 mm/kasan/common.c:641
 __asan_report_load1_noabort+0x14/0x20 mm/kasan/generic_report.c:132
 gadget_dev_desc_UDC_store+0x1ba/0x200 drivers/usb/gadget/configfs.c:266
 flush_write_buffer fs/configfs/file.c:251 [inline]
 configfs_write_file+0x2f1/0x4c0 fs/configfs/file.c:283
 __vfs_write+0x85/0x110 fs/read_write.c:494
 vfs_write+0x1cd/0x510 fs/read_write.c:558
 ksys_write+0x18a/0x220 fs/read_write.c:611
 __do_sys_write fs/read_write.c:623 [inline]
 __se_sys_write fs/read_write.c:620 [inline]
 __x64_sys_write+0x73/0xb0 fs/read_write.c:620
 do_syscall_64+0x9e/0x510 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Signed-off-by: Kyungtae Kim <kt0755@gmail.com>
Reported-and-tested-by: Kyungtae Kim <kt0755@gmail.com>
Cc: Felipe Balbi <balbi@kernel.org>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20200510054326.GA19198@pizza01
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
tlendacky pushed a commit that referenced this pull request Jun 24, 2020
call_undef_hook() in traps.c applies the same instr_mask for both 16-bit
and 32-bit thumb instructions. If instr_mask then is only 16 bits wide
(0xffff as opposed to 0xffffffff), the first half-word of 32-bit thumb
instructions will be masked out. This makes the function match 32-bit
thumb instructions where the second half-word is equal to instr_val,
regardless of the first half-word.

The result in this case is that all undefined 32-bit thumb instructions
with the second half-word equal to 0xde01 (udf #1) work as breakpoints
and will raise a SIGTRAP instead of a SIGILL, instead of just the one
intended 16-bit instruction. An example of such an instruction is
0xeaa0de01, which is unallocated according to Arm ARM and should raise a
SIGILL, but instead raises a SIGTRAP.

This patch fixes the issue by setting all the bits in instr_mask, which
will still match the intended 16-bit thumb instruction (where the
upper half is always 0), but not any 32-bit thumb instructions.

Cc: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Fredrik Strupe <fredrik@strupe.net>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
tlendacky pushed a commit that referenced this pull request Jun 24, 2020
This BUG halt was reported a while back, but the patch somehow got
missed:

PID: 2879   TASK: c16adaa0  CPU: 1   COMMAND: "sctpn"
 #0 [f418dd28] crash_kexec at c04a7d8c
 #1 [f418dd7c] oops_end at c0863e02
 #2 [f418dd90] do_invalid_op at c040aaca
 #3 [f418de28] error_code (via invalid_op) at c08631a5
    EAX: f34baac0  EBX: 00000090  ECX: f418deb0  EDX: f5542950  EBP: 00000000
    DS:  007b      ESI: f34ba800  ES:  007b      EDI: f418dea0  GS:  00e0
    CS:  0060      EIP: c046fa5e  ERR: ffffffff  EFLAGS: 00010286
 #4 [f418de5c] add_timer at c046fa5e
 #5 [f418de68] sctp_do_sm at f8db8c77 [sctp]
 #6 [f418df30] sctp_primitive_SHUTDOWN at f8dcc1b5 [sctp]
 torvalds#7 [f418df48] inet_shutdown at c080baf9
 torvalds#8 [f418df5c] sys_shutdown at c079eedf
 torvalds#9 [f418df7] sys_socketcall at c079fe88
    EAX: ffffffda  EBX: 0000000d  ECX: bfceea90  EDX: 0937af98
    DS:  007b      ESI: 0000000c  ES:  007b      EDI: b7150ae4
    SS:  007b      ESP: bfceea7c  EBP: bfceeaa8  GS:  0033
    CS:  0073      EIP: b775c424  ERR: 00000066  EFLAGS: 00000282

It appears that the side effect that starts the shutdown timer was processed
multiple times, which can happen as multiple paths can trigger it.  This of
course leads to the BUG halt in add_timer getting called.

Fix seems pretty straightforward, just check before the timer is added if its
already been started.  If it has mod the timer instead to min(current
expiration, new expiration)

Its been tested but not confirmed to fix the problem, as the issue has only
occured in production environments where test kernels are enjoined from being
installed.  It appears to be a sane fix to me though.  Also, recentely,
Jere found a reproducer posted on list to confirm that this resolves the
issues

Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
CC: Vlad Yasevich <vyasevich@gmail.com>
CC: "David S. Miller" <davem@davemloft.net>
CC: jere.leppanen@nokia.com
CC: marcelo.leitner@gmail.com
CC: netdev@vger.kernel.org
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
tlendacky pushed a commit that referenced this pull request Jun 24, 2020
In null_init_zone_dev() check if the zone size is larger than device
capacity, return error if needed.

This also fixes the following oops :-

null_blk: changed the number of conventional zones to 4294967295
BUG: kernel NULL pointer dereference, address: 0000000000000010
PGD 7d76c5067 P4D 7d76c5067 PUD 7d240c067 PMD 0
Oops: 0002 [#1] SMP NOPTI
CPU: 4 PID: 5508 Comm: nullbtests.sh Tainted: G OE 5.7.0-rc4lblk-fnext0
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.0-59-gc9ba5276e4
RIP: 0010:null_init_zoned_dev+0x17a/0x27f [null_blk]
RSP: 0018:ffffc90007007e00 EFLAGS: 00010246
RAX: 0000000000000020 RBX: ffff8887fb3f3c00 RCX: 0000000000000007
RDX: 0000000000000000 RSI: ffff8887ca09d688 RDI: ffff888810fea510
RBP: 0000000000000010 R08: ffff8887ca09d688 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffff8887c26e8000
R13: ffffffffa05e9390 R14: 0000000000000000 R15: 0000000000000001
FS:  00007fcb5256f740(0000) GS:ffff888810e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000010 CR3: 000000081e8fe000 CR4: 00000000003406e0
Call Trace:
 null_add_dev+0x534/0x71b [null_blk]
 nullb_device_power_store.cold.41+0x8/0x2e [null_blk]
 configfs_write_file+0xe6/0x150
 vfs_write+0xba/0x1e0
 ksys_write+0x5f/0xe0
 do_syscall_64+0x60/0x250
 entry_SYSCALL_64_after_hwframe+0x49/0xb3
RIP: 0033:0x7fcb51c71840

Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
tlendacky pushed a commit that referenced this pull request Jun 24, 2020
q_deferred_work isn't initialized when creating an explicit ODP memory
region. This can lead to a NULL pointer dereference when user performs
asynchronous prefetch MR. Fix it by initializing q_deferred_work for
explicit ODP.

  BUG: kernel NULL pointer dereference, address: 0000000000000000
  #PF: supervisor read access in kernel mode
  #PF: error_code(0x0000) - not-present page
  PGD 0 P4D 0
  Oops: 0000 [#1] SMP PTI
  CPU: 4 PID: 6074 Comm: kworker/u16:6 Not tainted 5.7.0-rc1-for-upstream-perf-2020-04-17_07-03-39-64 #1
  Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.12.1-0-ga5cab58e9a3f-prebuilt.qemu.org 04/01/2014
  Workqueue: events_unbound mlx5_ib_prefetch_mr_work [mlx5_ib]
  RIP: 0010:__wake_up_common+0x49/0x120
  Code: 04 89 54 24 0c 89 4c 24 08 74 0a 41 f6 01 04 0f 85 8e 00 00 00 48 8b 47 08 48 83 e8 18 4c 8d 67 08 48 8d 50 18 49 39 d4 74 66 <48> 8b 70 18 31 db 4c 8d 7e e8 eb 17 49 8b 47 18 48 8d 50 e8 49 8d
  RSP: 0000:ffffc9000097bd88 EFLAGS: 00010082
  RAX: ffffffffffffffe8 RBX: ffff888454cd9f90 RCX: 0000000000000000
  RDX: 0000000000000000 RSI: 0000000000000003 RDI: ffff888454cd9f90
  RBP: ffffc9000097bdd0 R08: 0000000000000000 R09: ffffc9000097bdd0
  R10: 0000000000000000 R11: 0000000000000001 R12: ffff888454cd9f98
  R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000003
  FS:  0000000000000000(0000) GS:ffff88846fd00000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 0000000000000000 CR3: 000000044c19e002 CR4: 0000000000760ee0
  DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
  PKRU: 55555554
  Call Trace:
   __wake_up_common_lock+0x7a/0xc0
   destroy_prefetch_work+0x5a/0x60 [mlx5_ib]
   mlx5_ib_prefetch_mr_work+0x64/0x80 [mlx5_ib]
   process_one_work+0x15b/0x360
   worker_thread+0x49/0x3d0
   kthread+0xf5/0x130
   ? rescuer_thread+0x310/0x310
   ? kthread_bind+0x10/0x10
   ret_from_fork+0x1f/0x30

Fixes: de5ed00 ("IB/mlx5: Fix implicit ODP race")
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20200521072504.567406-1-leon@kernel.org
Signed-off-by: Maor Gottlieb <maorg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
tlendacky pushed a commit that referenced this pull request Jun 24, 2020
Ido Schimmel says:

====================
netdevsim: Two small fixes

Fix two bugs observed while analyzing regression failures.

Patch #1 fixes a bug where sometimes the drop counter of a packet trap
policer would not increase.

Patch #2 adds a missing initialization of a variable in a related
selftest.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
tlendacky pushed a commit that referenced this pull request Jun 24, 2020
Ido Schimmel says:

====================
mlxsw: Various fixes

Patch #1 from Jiri fixes a use-after-free discovered while fuzzing mlxsw
/ devlink with syzkaller.

Patch #2 from Amit works around a limitation in new versions of arping,
which is used in several selftests.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
tlendacky pushed a commit that referenced this pull request Jun 24, 2020
On a non-forwarding 802.11s link between two fairly busy
neighboring nodes (iperf with -P 16 at ~850MBit/s TCP;
1733.3 MBit/s VHT-MCS 9 80MHz short GI VHT-NSS 4), so with
frequent PREQ retries, usually after around 30-40 seconds the
following crash would occur:

[ 1110.822428] Unable to handle kernel read from unreadable memory at virtual address 00000000
[ 1110.830786] Mem abort info:
[ 1110.833573]   Exception class = IABT (current EL), IL = 32 bits
[ 1110.839494]   SET = 0, FnV = 0
[ 1110.842546]   EA = 0, S1PTW = 0
[ 1110.845678] user pgtable: 4k pages, 48-bit VAs, pgd = ffff800076386000
[ 1110.852204] [0000000000000000] *pgd=00000000f6322003, *pud=00000000f62de003, *pmd=0000000000000000
[ 1110.861167] Internal error: Oops: 86000004 [#1] PREEMPT SMP
[ 1110.866730] Modules linked in: pppoe ppp_async batman_adv ath10k_pci ath10k_core ath pppox ppp_generic nf_conntrack_ipv6 mac80211 iptable_nat ipt_REJECT ipt_MASQUERADE cfg80211 xt_time xt_tcpudp xt_state xt_nat xt_multiport xt_mark xt_mac xt_limit xt_conntrack xt_comment xt_TCPMSS xt_REDIRECT xt_LOG xt_FLOWOFFLOAD slhc nf_reject_ipv4 nf_nat_redirect nf_nat_masquerade_ipv4 nf_conntrack_ipv4 nf_nat_ipv4 nf_nat nf_log_ipv4 nf_flow_table_hw nf_flow_table nf_defrag_ipv6 nf_defrag_ipv4 nf_conntrack_rtcache nf_conntrack iptable_mangle iptable_filter ip_tables crc_ccitt compat nf_log_ipv6 nf_log_common ip6table_mangle ip6table_filter ip6_tables ip6t_REJECT x_tables nf_reject_ipv6 usb_storage xhci_plat_hcd xhci_pci xhci_hcd dwc3 usbcore usb_common
[ 1110.932190] Process swapper/3 (pid: 0, stack limit = 0xffff0000090c8000)
[ 1110.938884] CPU: 3 PID: 0 Comm: swapper/3 Not tainted 4.14.162 #0
[ 1110.944965] Hardware name: LS1043A RGW Board (DT)
[ 1110.949658] task: ffff8000787a81c0 task.stack: ffff0000090c8000
[ 1110.955568] PC is at 0x0
[ 1110.958097] LR is at call_timer_fn.isra.27+0x24/0x78
[ 1110.963055] pc : [<0000000000000000>] lr : [<ffff0000080ff29c>] pstate: 00400145
[ 1110.970440] sp : ffff00000801be10
[ 1110.973744] x29: ffff00000801be10 x28: ffff000008bf7018
[ 1110.979047] x27: ffff000008bf87c8 x26: ffff000008c160c0
[ 1110.984352] x25: 0000000000000000 x24: 0000000000000000
[ 1110.989657] x23: dead000000000200 x22: 0000000000000000
[ 1110.994959] x21: 0000000000000000 x20: 0000000000000101
[ 1111.000262] x19: ffff8000787a81c0 x18: 0000000000000000
[ 1111.005565] x17: ffff0000089167b0 x16: 0000000000000058
[ 1111.010868] x15: ffff0000089167b0 x14: 0000000000000000
[ 1111.016172] x13: ffff000008916788 x12: 0000000000000040
[ 1111.021475] x11: ffff80007fda9af0 x10: 0000000000000001
[ 1111.026777] x9 : ffff00000801bea0 x8 : 0000000000000004
[ 1111.032080] x7 : 0000000000000000 x6 : ffff80007fda9aa8
[ 1111.037383] x5 : ffff00000801bea0 x4 : 0000000000000010
[ 1111.042685] x3 : ffff00000801be98 x2 : 0000000000000614
[ 1111.047988] x1 : 0000000000000000 x0 : 0000000000000000
[ 1111.053290] Call trace:
[ 1111.055728] Exception stack(0xffff00000801bcd0 to 0xffff00000801be10)
[ 1111.062158] bcc0:                                   0000000000000000 0000000000000000
[ 1111.069978] bce0: 0000000000000614 ffff00000801be98 0000000000000010 ffff00000801bea0
[ 1111.077798] bd00: ffff80007fda9aa8 0000000000000000 0000000000000004 ffff00000801bea0
[ 1111.085618] bd20: 0000000000000001 ffff80007fda9af0 0000000000000040 ffff000008916788
[ 1111.093437] bd40: 0000000000000000 ffff0000089167b0 0000000000000058 ffff0000089167b0
[ 1111.101256] bd60: 0000000000000000 ffff8000787a81c0 0000000000000101 0000000000000000
[ 1111.109075] bd80: 0000000000000000 dead000000000200 0000000000000000 0000000000000000
[ 1111.116895] bda0: ffff000008c160c0 ffff000008bf87c8 ffff000008bf7018 ffff00000801be10
[ 1111.124715] bdc0: ffff0000080ff29c ffff00000801be10 0000000000000000 0000000000400145
[ 1111.132534] bde0: ffff8000787a81c0 ffff00000801bde8 0000ffffffffffff 000001029eb19be8
[ 1111.140353] be00: ffff00000801be10 0000000000000000
[ 1111.145220] [<          (null)>]           (null)
[ 1111.149917] [<ffff0000080ff77c>] run_timer_softirq+0x184/0x398
[ 1111.155741] [<ffff000008081938>] __do_softirq+0x100/0x1fc
[ 1111.161130] [<ffff0000080a2e28>] irq_exit+0x80/0xd8
[ 1111.166002] [<ffff0000080ea708>] __handle_domain_irq+0x88/0xb0
[ 1111.171825] [<ffff000008081678>] gic_handle_irq+0x68/0xb0
[ 1111.177213] Exception stack(0xffff0000090cbe30 to 0xffff0000090cbf70)
[ 1111.183642] be20:                                   0000000000000020 0000000000000000
[ 1111.191461] be40: 0000000000000001 0000000000000000 00008000771af000 0000000000000000
[ 1111.199281] be60: ffff000008c95180 0000000000000000 ffff000008c19360 ffff0000090cbef0
[ 1111.207101] be80: 0000000000000810 0000000000000400 0000000000000098 ffff000000000000
[ 1111.214920] bea0: 0000000000000001 ffff0000089167b0 0000000000000000 ffff0000089167b0
[ 1111.222740] bec0: 0000000000000000 ffff000008c198e8 ffff000008bf7018 ffff000008c19000
[ 1111.230559] bee0: 0000000000000000 0000000000000000 ffff8000787a81c0 ffff000008018000
[ 1111.238380] bf00: ffff00000801c000 ffff00000913ba34 ffff8000787a81c0 ffff0000090cbf70
[ 1111.246199] bf20: ffff0000080857cc ffff0000090cbf70 ffff0000080857d0 0000000000400145
[ 1111.254020] bf40: ffff000008018000 ffff00000801c000 ffffffffffffffff ffff0000080fa574
[ 1111.261838] bf60: ffff0000090cbf70 ffff0000080857d0
[ 1111.266706] [<ffff0000080832e8>] el1_irq+0xe8/0x18c
[ 1111.271576] [<ffff0000080857d0>] arch_cpu_idle+0x10/0x18
[ 1111.276880] [<ffff0000080d7de4>] do_idle+0xec/0x1b8
[ 1111.281748] [<ffff0000080d8020>] cpu_startup_entry+0x20/0x28
[ 1111.287399] [<ffff00000808f81c>] secondary_start_kernel+0x104/0x110
[ 1111.293662] Code: bad PC value
[ 1111.296710] ---[ end trace 555b6ca4363c3edd ]---
[ 1111.301318] Kernel panic - not syncing: Fatal exception in interrupt
[ 1111.307661] SMP: stopping secondary CPUs
[ 1111.311574] Kernel Offset: disabled
[ 1111.315053] CPU features: 0x0002000
[ 1111.318530] Memory Limit: none
[ 1111.321575] Rebooting in 3 seconds..

With some added debug output / delays we were able to push the crash from
the timer callback runner into the callback function and by that shedding
some light on which object holding the timer gets corrupted:

[  401.720899] Unable to handle kernel read from unreadable memory at virtual address 00000868
[...]
[  402.335836] [<ffff0000088fafa4>] _raw_spin_lock_bh+0x14/0x48
[  402.341548] [<ffff000000dbe684>] mesh_path_timer+0x10c/0x248 [mac80211]
[  402.348154] [<ffff0000080ff29c>] call_timer_fn.isra.27+0x24/0x78
[  402.354150] [<ffff0000080ff77c>] run_timer_softirq+0x184/0x398
[  402.359974] [<ffff000008081938>] __do_softirq+0x100/0x1fc
[  402.365362] [<ffff0000080a2e28>] irq_exit+0x80/0xd8
[  402.370231] [<ffff0000080ea708>] __handle_domain_irq+0x88/0xb0
[  402.376053] [<ffff000008081678>] gic_handle_irq+0x68/0xb0

The issue happens due to the following sequence of events:

1) mesh_path_start_discovery():
-> spin_unlock_bh(&mpath->state_lock) before mesh_path_sel_frame_tx()

2) mesh_path_free_rcu()
-> del_timer_sync(&mpath->timer)
   [...]
-> kfree_rcu(mpath)

3) mesh_path_start_discovery():
-> mod_timer(&mpath->timer, ...)
   [...]
-> rcu_read_unlock()

4) mesh_path_free_rcu()'s kfree_rcu():
-> kfree(mpath)

5) mesh_path_timer() starts after timeout, using freed mpath object

So a use-after-free issue due to a timer re-arming bug caused by an
early spin-unlocking.

This patch fixes this issue by re-checking if mpath is about to be
free'd and if so bails out of re-arming the timer.

Cc: stable@vger.kernel.org
Fixes: 050ac52 ("mac80211: code for on-demand Hybrid Wireless Mesh Protocol")
Cc: Simon Wunderlich <sw@simonwunderlich.de>
Signed-off-by: Linus Lüssing <ll@simonwunderlich.de>
Link: https://lore.kernel.org/r/20200522170413.14973-1-linus.luessing@c0d3.blue
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
tlendacky pushed a commit that referenced this pull request Jun 24, 2020
In the MPTCP receive path we must cope with TCP fallback
on blocking recvmsg(). Currently in such code path we detect
the fallback condition, but we don't fetch the struct socket
required for fallback.

The above allowed syzkaller to trigger a NULL pointer
dereference:

general protection fault, probably for non-canonical address 0xdffffc0000000004: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000020-0x0000000000000027]
CPU: 1 PID: 7226 Comm: syz-executor523 Not tainted 5.7.0-rc6-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:sock_recvmsg_nosec net/socket.c:886 [inline]
RIP: 0010:sock_recvmsg+0x92/0x110 net/socket.c:904
Code: 5b 41 5c 41 5d 41 5e 41 5f 5d c3 44 89 6c 24 04 e8 53 18 1d fb 4d 8d 6f 20 4c 89 e8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df <80> 3c 08 00 74 08 4c 89 ef e8 20 12 5b fb bd a0 00 00 00 49 03 6d
RSP: 0018:ffffc90001077b98 EFLAGS: 00010202
RAX: 0000000000000004 RBX: ffffc90001077dc0 RCX: dffffc0000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: ffffffff86565e59 R09: ffffed10115afeaa
R10: ffffed10115afeaa R11: 0000000000000000 R12: 1ffff9200020efbc
R13: 0000000000000020 R14: ffffc90001077de0 R15: 0000000000000000
FS:  00007fc6a3abe700(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000004d0050 CR3: 00000000969f0000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 mptcp_recvmsg+0x18d5/0x19b0 net/mptcp/protocol.c:891
 inet_recvmsg+0xf6/0x1d0 net/ipv4/af_inet.c:838
 sock_recvmsg_nosec net/socket.c:886 [inline]
 sock_recvmsg net/socket.c:904 [inline]
 __sys_recvfrom+0x2f3/0x470 net/socket.c:2057
 __do_sys_recvfrom net/socket.c:2075 [inline]
 __se_sys_recvfrom net/socket.c:2071 [inline]
 __x64_sys_recvfrom+0xda/0xf0 net/socket.c:2071
 do_syscall_64+0xf3/0x1b0 arch/x86/entry/common.c:295
 entry_SYSCALL_64_after_hwframe+0x49/0xb3

Address the issue initializing the struct socket reference
before entering the fallback code.

Reported-and-tested-by: syzbot+c6bfc3db991edc918432@syzkaller.appspotmail.com
Suggested-by: Ondrej Mosnacek <omosnace@redhat.com>
Fixes: 8ab183d ("mptcp: cope with later TCP fallback")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
tlendacky pushed a commit that referenced this pull request Jun 24, 2020
Be there a platform with the following layout:

      Regular NIC
       |
       +----> DSA master for switch port
               |
               +----> DSA master for another switch port

After changing DSA back to static lockdep class keys in commit
1a33e10 ("net: partially revert dynamic lockdep key changes"), this
kernel splat can be seen:

[   13.361198] ============================================
[   13.366524] WARNING: possible recursive locking detected
[   13.371851] 5.7.0-rc4-02121-gc32a05ecd7af-dirty torvalds#988 Not tainted
[   13.377874] --------------------------------------------
[   13.383201] swapper/0/0 is trying to acquire lock:
[   13.388004] ffff0000668ff298 (&dsa_slave_netdev_xmit_lock_key){+.-.}-{2:2}, at: __dev_queue_xmit+0x84c/0xbe0
[   13.397879]
[   13.397879] but task is already holding lock:
[   13.403727] ffff0000661a1698 (&dsa_slave_netdev_xmit_lock_key){+.-.}-{2:2}, at: __dev_queue_xmit+0x84c/0xbe0
[   13.413593]
[   13.413593] other info that might help us debug this:
[   13.420140]  Possible unsafe locking scenario:
[   13.420140]
[   13.426075]        CPU0
[   13.428523]        ----
[   13.430969]   lock(&dsa_slave_netdev_xmit_lock_key);
[   13.435946]   lock(&dsa_slave_netdev_xmit_lock_key);
[   13.440924]
[   13.440924]  *** DEADLOCK ***
[   13.440924]
[   13.446860]  May be due to missing lock nesting notation
[   13.446860]
[   13.453668] 6 locks held by swapper/0/0:
[   13.457598]  #0: ffff800010003de0 ((&idev->mc_ifc_timer)){+.-.}-{0:0}, at: call_timer_fn+0x0/0x400
[   13.466593]  #1: ffffd4d3fb478700 (rcu_read_lock){....}-{1:2}, at: mld_sendpack+0x0/0x560
[   13.474803]  #2: ffffd4d3fb478728 (rcu_read_lock_bh){....}-{1:2}, at: ip6_finish_output2+0x64/0xb10
[   13.483886]  #3: ffffd4d3fb478728 (rcu_read_lock_bh){....}-{1:2}, at: __dev_queue_xmit+0x6c/0xbe0
[   13.492793]  #4: ffff0000661a1698 (&dsa_slave_netdev_xmit_lock_key){+.-.}-{2:2}, at: __dev_queue_xmit+0x84c/0xbe0
[   13.503094]  #5: ffffd4d3fb478728 (rcu_read_lock_bh){....}-{1:2}, at: __dev_queue_xmit+0x6c/0xbe0
[   13.512000]
[   13.512000] stack backtrace:
[   13.516369] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.7.0-rc4-02121-gc32a05ecd7af-dirty torvalds#988
[   13.530421] Call trace:
[   13.532871]  dump_backtrace+0x0/0x1d8
[   13.536539]  show_stack+0x24/0x30
[   13.539862]  dump_stack+0xe8/0x150
[   13.543271]  __lock_acquire+0x1030/0x1678
[   13.547290]  lock_acquire+0xf8/0x458
[   13.550873]  _raw_spin_lock+0x44/0x58
[   13.554543]  __dev_queue_xmit+0x84c/0xbe0
[   13.558562]  dev_queue_xmit+0x24/0x30
[   13.562232]  dsa_slave_xmit+0xe0/0x128
[   13.565988]  dev_hard_start_xmit+0xf4/0x448
[   13.570182]  __dev_queue_xmit+0x808/0xbe0
[   13.574200]  dev_queue_xmit+0x24/0x30
[   13.577869]  neigh_resolve_output+0x15c/0x220
[   13.582237]  ip6_finish_output2+0x244/0xb10
[   13.586430]  __ip6_finish_output+0x1dc/0x298
[   13.590709]  ip6_output+0x84/0x358
[   13.594116]  mld_sendpack+0x2bc/0x560
[   13.597786]  mld_ifc_timer_expire+0x210/0x390
[   13.602153]  call_timer_fn+0xcc/0x400
[   13.605822]  run_timer_softirq+0x588/0x6e0
[   13.609927]  __do_softirq+0x118/0x590
[   13.613597]  irq_exit+0x13c/0x148
[   13.616918]  __handle_domain_irq+0x6c/0xc0
[   13.621023]  gic_handle_irq+0x6c/0x160
[   13.624779]  el1_irq+0xbc/0x180
[   13.627927]  cpuidle_enter_state+0xb4/0x4d0
[   13.632120]  cpuidle_enter+0x3c/0x50
[   13.635703]  call_cpuidle+0x44/0x78
[   13.639199]  do_idle+0x228/0x2c8
[   13.642433]  cpu_startup_entry+0x2c/0x48
[   13.646363]  rest_init+0x1ac/0x280
[   13.649773]  arch_call_rest_init+0x14/0x1c
[   13.653878]  start_kernel+0x490/0x4bc

Lockdep keys themselves were added in commit ab92d68 ("net: core:
add generic lockdep keys"), and it's very likely that this splat existed
since then, but I have no real way to check, since this stacked platform
wasn't supported by mainline back then.

>From Taehee's own words:

  This patch was considered that all stackable devices have LLTX flag.
  But the dsa doesn't have LLTX, so this splat happened.
  After this patch, dsa shares the same lockdep class key.
  On the nested dsa interface architecture, which you illustrated,
  the same lockdep class key will be used in __dev_queue_xmit() because
  dsa doesn't have LLTX.
  So that lockdep detects deadlock because the same lockdep class key is
  used recursively although actually the different locks are used.
  There are some ways to fix this problem.

  1. using NETIF_F_LLTX flag.
  If possible, using the LLTX flag is a very clear way for it.
  But I'm so sorry I don't know whether the dsa could have LLTX or not.

  2. using dynamic lockdep again.
  It means that each interface uses a separate lockdep class key.
  So, lockdep will not detect recursive locking.
  But this way has a problem that it could consume lockdep class key
  too many.
  Currently, lockdep can have 8192 lockdep class keys.
   - you can see this number with the following command.
     cat /proc/lockdep_stats
     lock-classes:                         1251 [max: 8192]
     ...
     The [max: 8192] means that the maximum number of lockdep class keys.
  If too many lockdep class keys are registered, lockdep stops to work.
  So, using a dynamic(separated) lockdep class key should be considered
  carefully.
  In addition, updating lockdep class key routine might have to be existing.
  (lockdep_register_key(), lockdep_set_class(), lockdep_unregister_key())

  3. Using lockdep subclass.
  A lockdep class key could have 8 subclasses.
  The different subclass is considered different locks by lockdep
  infrastructure.
  But "lock-classes" is not counted by subclasses.
  So, it could avoid stopping lockdep infrastructure by an overflow of
  lockdep class keys.
  This approach should also have an updating lockdep class key routine.
  (lockdep_set_subclass())

  4. Using nonvalidate lockdep class key.
  The lockdep infrastructure supports nonvalidate lockdep class key type.
  It means this lockdep is not validated by lockdep infrastructure.
  So, the splat will not happen but lockdep couldn't detect real deadlock
  case because lockdep really doesn't validate it.
  I think this should be used for really special cases.
  (lockdep_set_novalidate_class())

Further discussion here:
https://patchwork.ozlabs.org/project/netdev/patch/20200503052220.4536-2-xiyou.wangcong@gmail.com/

There appears to be no negative side-effect to declaring lockless TX for
the DSA virtual interfaces, which means they handle their own locking.
So that's what we do to make the splat go away.

Patch tested in a wide variety of cases: unicast, multicast, PTP, etc.

Fixes: ab92d68 ("net: core: add generic lockdep keys")
Suggested-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
tlendacky pushed a commit that referenced this pull request Jun 24, 2020
The intermediate result of the old term (4UL * 1024 * 1024 * 1024) is
4 294 967 296 or 0x100000000 which is no problem on 64 bit systems.
The patch does not change the later overall result of 0x100000 for
MAX_DMA32_PFN (after it has been shifted by PAGE_SHIFT). The new
calculation yields the same result, but does not require 64 bit
arithmetic.

On 32 bit systems the old calculation suffers from an arithmetic
overflow in that intermediate term in braces: 4UL aka unsigned long int
is 4 byte wide and an arithmetic overflow happens (the 0x100000000 does
not fit in 4 bytes), the in braces result is truncated to zero, the
following right shift does not alter that, so MAX_DMA32_PFN evaluates to
0 on 32 bit systems.

That wrong value is a problem in a comparision against MAX_DMA32_PFN in
the init code for swiotlb in pci_swiotlb_detect_4gb() to decide if
swiotlb should be active.  That comparison yields the opposite result,
when compiling on 32 bit systems.

This was not possible before

  1b7e03e ("x86, NUMA: Enable emulation on 32bit too")

when that MAX_DMA32_PFN was first made visible to x86_32 (and which
landed in v3.0).

In practice this wasn't a problem, unless CONFIG_SWIOTLB is active on
x86-32.

However if one has set CONFIG_IOMMU_INTEL, since

  c5a5dc4 ("iommu/vt-d: Don't switch off swiotlb if bounce page is used")

there's a dependency on CONFIG_SWIOTLB, which was not necessarily
active before. That landed in v5.4, where we noticed it in the fli4l
Linux distribution. We have CONFIG_IOMMU_INTEL active on both 32 and 64
bit kernel configs there (I could not find out why, so let's just say
historical reasons).

The effect is at boot time 64 MiB (default size) were allocated for
bounce buffers now, which is a noticeable amount of memory on small
systems like pcengines ALIX 2D3 with 256 MiB memory, which are still
frequently used as home routers.

We noticed this effect when migrating from kernel v4.19 (LTS) to v5.4
(LTS) in fli4l and got that kernel messages for example:

  Linux version 5.4.22 (buildroot@buildroot) (gcc version 7.3.0 (Buildroot 2018.02.8)) #1 SMP Mon Nov 26 23:40:00 CET 2018
  …
  Memory: 183484K/261756K available (4594K kernel code, 393K rwdata, 1660K rodata, 536K init, 456K bss , 78272K reserved, 0K cma-reserved, 0K highmem)
  …
  PCI-DMA: Using software bounce buffering for IO (SWIOTLB)
  software IO TLB: mapped [mem 0x0bb78000-0x0fb78000] (64MB)

The initial analysis and the suggested fix was done by user 'sourcejedi'
at stackoverflow and explicitly marked as GPLv2 for inclusion in the
Linux kernel:

  https://unix.stackexchange.com/a/520525/50007

The new calculation, which does not suffer from that overflow, is the
same as for arch/mips now as suggested by Robin Murphy.

The fix was tested by fli4l users on round about two dozen different
systems, including both 32 and 64 bit archs, bare metal and virtualized
machines.

 [ bp: Massage commit message. ]

Fixes: 1b7e03e ("x86, NUMA: Enable emulation on 32bit too")
Reported-by: Alan Jenkins <alan.christopher.jenkins@gmail.com>
Suggested-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Alexander Dahl <post@lespocky.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: stable@vger.kernel.org
Link: https://unix.stackexchange.com/q/520065/50007
Link: https://web.nettworks.org/bugs/browse/FFL-2560
Link: https://lkml.kernel.org/r/20200526175749.20742-1-post@lespocky.de
tlendacky pushed a commit that referenced this pull request Jun 24, 2020
Replace superfluous VM_BUG_ON() with comment about correct usage.

Technically reverts commit 1d148e2 ("mm: add VM_BUG_ON_PAGE() to
page_mapcount()"), but context lines have changed.

Function isolate_migratepages_block() runs some checks out of lru_lock
when choose pages for migration.  After checking PageLRU() it checks
extra page references by comparing page_count() and page_mapcount().
Between these two checks page could be removed from lru, freed and taken
by slab.

As a result this race triggers VM_BUG_ON(PageSlab()) in page_mapcount().
Race window is tiny.  For certain workload this happens around once a
year.

    page:ffffea0105ca9380 count:1 mapcount:0 mapping:ffff88ff7712c180 index:0x0 compound_mapcount: 0
    flags: 0x500000000008100(slab|head)
    raw: 0500000000008100 dead000000000100 dead000000000200 ffff88ff7712c180
    raw: 0000000000000000 0000000080200020 00000001ffffffff 0000000000000000
    page dumped because: VM_BUG_ON_PAGE(PageSlab(page))
    ------------[ cut here ]------------
    kernel BUG at ./include/linux/mm.h:628!
    invalid opcode: 0000 [#1] SMP NOPTI
    CPU: 77 PID: 504 Comm: kcompactd1 Tainted: G        W         4.19.109-27 #1
    Hardware name: Yandex T175-N41-Y3N/MY81-EX0-Y3N, BIOS R05 06/20/2019
    RIP: 0010:isolate_migratepages_block+0x986/0x9b0

The code in isolate_migratepages_block() was added in commit
119d6d5 ("mm, compaction: avoid isolating pinned pages") before
adding VM_BUG_ON into page_mapcount().

This race has been predicted in 2015 by Vlastimil Babka (see link
below).

[akpm@linux-foundation.org: comment tweaks, per Hugh]
Fixes: 1d148e2 ("mm: add VM_BUG_ON_PAGE() to page_mapcount()")
Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Hugh Dickins <hughd@google.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: David Rientjes <rientjes@google.com>
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/159032779896.957378.7852761411265662220.stgit@buzz
Link: https://lore.kernel.org/lkml/557710E1.6060103@suse.cz/
Link: https://lore.kernel.org/linux-mm/158937872515.474360.5066096871639561424.stgit@buzz/T/ (v1)
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
tlendacky pushed a commit that referenced this pull request Jun 24, 2020
This patch is to fix a crash:

  [ ] kasan: GPF could be caused by NULL-ptr deref or user memory access
  [ ] general protection fault: 0000 [#1] SMP KASAN PTI
  [ ] RIP: 0010:ipv6_local_error+0xac/0x7a0
  [ ] Call Trace:
  [ ]  xfrm6_local_error+0x1eb/0x300
  [ ]  xfrm_local_error+0x95/0x130
  [ ]  __xfrm6_output+0x65f/0xb50
  [ ]  xfrm6_output+0x106/0x46f
  [ ]  udp_tunnel6_xmit_skb+0x618/0xbf0 [ip6_udp_tunnel]
  [ ]  vxlan_xmit_one+0xbc6/0x2c60 [vxlan]
  [ ]  vxlan_xmit+0x6a0/0x4276 [vxlan]
  [ ]  dev_hard_start_xmit+0x165/0x820
  [ ]  __dev_queue_xmit+0x1ff0/0x2b90
  [ ]  ip_finish_output2+0xd3e/0x1480
  [ ]  ip_do_fragment+0x182d/0x2210
  [ ]  ip_output+0x1d0/0x510
  [ ]  ip_send_skb+0x37/0xa0
  [ ]  raw_sendmsg+0x1b4c/0x2b80
  [ ]  sock_sendmsg+0xc0/0x110

This occurred when sending a v4 skb over vxlan6 over ipsec, in which case
skb->protocol == htons(ETH_P_IPV6) while skb->sk->sk_family == AF_INET in
xfrm_local_error(). Then it will go to xfrm6_local_error() where it tries
to get ipv6 info from a ipv4 sk.

This issue was actually fixed by Commit 628e341 ("xfrm: make local
error reporting more robust"), but brought back by Commit 844d487
("xfrm: choose protocol family by skb protocol").

So to fix it, we should call xfrm6_local_error() only when skb->protocol
is htons(ETH_P_IPV6) and skb->sk->sk_family is AF_INET6.

Fixes: 844d487 ("xfrm: choose protocol family by skb protocol")
Reported-by: Xiumei Mu <xmu@redhat.com>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
mdroth pushed a commit that referenced this pull request Oct 10, 2025
Patch series "mm/damon: fix divide by zero and its samples", v3.

This series includes fixes against damon and its samples to make it safer
when damon sample starting fails.

It includes the following changes.
- fix unexpected divide by zero crash for zero size regions
- fix bugs for damon samples in case of start failures


This patch (of 4):

The damon_sample_prcl_start() can fail so we must reset the "enable"
parameter to "false" again for proper rollback.

In such cases, setting Y to "enable" then N triggers the following crash
because damon sample start failed but the "enable" stays as Y.

  [ 2441.419649] damon_sample_prcl: start
  [ 2454.146817] damon_sample_prcl: stop
  [ 2454.146862] ------------[ cut here ]------------
  [ 2454.146865] kernel BUG at mm/slub.c:546!
  [ 2454.148183] Oops: invalid opcode: 0000 [#1] SMP NOPTI
  	...
  [ 2454.167555] Call Trace:
  [ 2454.167822]  <TASK>
  [ 2454.168061]  damon_destroy_ctx+0x78/0x140
  [ 2454.168454]  damon_sample_prcl_enable_store+0x8d/0xd0
  [ 2454.168932]  param_attr_store+0xa1/0x120
  [ 2454.169315]  module_attr_store+0x20/0x50
  [ 2454.169695]  sysfs_kf_write+0x72/0x90
  [ 2454.170065]  kernfs_fop_write_iter+0x150/0x1e0
  [ 2454.170491]  vfs_write+0x315/0x440
  [ 2454.170833]  ksys_write+0x69/0xf0
  [ 2454.171162]  __x64_sys_write+0x19/0x30
  [ 2454.171525]  x64_sys_call+0x18b2/0x2700
  [ 2454.171900]  do_syscall_64+0x7f/0x680
  [ 2454.172258]  ? exit_to_user_mode_loop+0xf6/0x180
  [ 2454.172694]  ? clear_bhb_loop+0x30/0x80
  [ 2454.173067]  ? clear_bhb_loop+0x30/0x80
  [ 2454.173439]  entry_SYSCALL_64_after_hwframe+0x76/0x7e

Link: https://lkml.kernel.org/r/20250702000205.1921-1-honggyu.kim@sk.com
Link: https://lkml.kernel.org/r/20250702000205.1921-2-honggyu.kim@sk.com
Fixes: 2aca254 ("samples/damon: introduce a skeleton of a smaple DAMON module for proactive reclamation")
Signed-off-by: Honggyu Kim <honggyu.kim@sk.com>
Reviewed-by: SeongJae Park <sj@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
mdroth pushed a commit that referenced this pull request Oct 10, 2025
The current implementation allows having zero size regions with no special
reasons, but damon_get_intervals_score() gets crashed by divide by zero
when the region size is zero.

  [   29.403950] Oops: divide error: 0000 [#1] SMP NOPTI

This patch fixes the bug, but does not disallow zero size regions to keep
the backward compatibility since disallowing zero size regions might be a
breaking change for some users.

In addition, the same crash can happen when intervals_goal.access_bp is
zero so this should be fixed in stable trees as well.

Link: https://lkml.kernel.org/r/20250702000205.1921-5-honggyu.kim@sk.com
Fixes: f04b0fe ("mm/damon/core: implement intervals auto-tuning")
Signed-off-by: Honggyu Kim <honggyu.kim@sk.com>
Reviewed-by: SeongJae Park <sj@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
mdroth pushed a commit that referenced this pull request Oct 10, 2025
If "try_verify_in_tasklet" is set for dm-verity, DM_BUFIO_CLIENT_NO_SLEEP
is enabled for dm-bufio. However, when bufio tries to evict buffers, there
is a chance to trigger scheduling in spin_lock_bh, the following warning
is hit:

BUG: sleeping function called from invalid context at drivers/md/dm-bufio.c:2745
in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 123, name: kworker/2:2
preempt_count: 201, expected: 0
RCU nest depth: 0, expected: 0
4 locks held by kworker/2:2/123:
 #0: ffff88800a2d1548 ((wq_completion)dm_bufio_cache){....}-{0:0}, at: process_one_work+0xe46/0x1970
 #1: ffffc90000d97d20 ((work_completion)(&dm_bufio_replacement_work)){....}-{0:0}, at: process_one_work+0x763/0x1970
 #2: ffffffff8555b528 (dm_bufio_clients_lock){....}-{3:3}, at: do_global_cleanup+0x1ce/0x710
 #3: ffff88801d5820b8 (&c->spinlock){....}-{2:2}, at: do_global_cleanup+0x2a5/0x710
Preemption disabled at:
[<0000000000000000>] 0x0
CPU: 2 UID: 0 PID: 123 Comm: kworker/2:2 Not tainted 6.16.0-rc3-g90548c634bd0 torvalds#305 PREEMPT(voluntary)
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
Workqueue: dm_bufio_cache do_global_cleanup
Call Trace:
 <TASK>
 dump_stack_lvl+0x53/0x70
 __might_resched+0x360/0x4e0
 do_global_cleanup+0x2f5/0x710
 process_one_work+0x7db/0x1970
 worker_thread+0x518/0xea0
 kthread+0x359/0x690
 ret_from_fork+0xf3/0x1b0
 ret_from_fork_asm+0x1a/0x30
 </TASK>

That can be reproduced by:

  veritysetup format --data-block-size=4096 --hash-block-size=4096 /dev/vda /dev/vdb
  SIZE=$(blockdev --getsz /dev/vda)
  dmsetup create myverity -r --table "0 $SIZE verity 1 /dev/vda /dev/vdb 4096 4096 <data_blocks> 1 sha256 <root_hash> <salt> 1 try_verify_in_tasklet"
  mount /dev/dm-0 /mnt -o ro
  echo 102400 > /sys/module/dm_bufio/parameters/max_cache_size_bytes
  [read files in /mnt]

Cc: stable@vger.kernel.org	# v6.4+
Fixes: 450e8de ("dm bufio: improve concurrent IO performance")
Signed-off-by: Wang Shuai <wangshuai12@xiaomi.com>
Signed-off-by: Sheng Yong <shengyong1@xiaomi.com>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
mdroth pushed a commit that referenced this pull request Oct 10, 2025
This marks 0x29 as accelerometer address on Dell Precision 3551.

I followed previous works of Paul Menzel and Hans de Goede to verify it:

$ cd /sys/bus/pci/drivers/i801_smbus/0000\:00\:1f.4

$ ls -d i2c-?
i2c-0

$ sudo modprobe i2c-dev

$ sudo i2cdetect 0
WARNING! This program can confuse your I2C bus, cause data loss and worse!
I will probe file /dev/i2c-0.
I will probe address range 0x08-0x77.
Continue? [Y/n] Y
     0  1  2  3  4  5  6  7  8  9  a  b  c  d  e  f
00:                         08 -- -- -- -- -- -- --
10: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
20: -- -- -- -- -- -- -- -- -- 29 -- -- -- -- -- --
30: 30 -- -- -- -- 35 UU UU -- -- -- -- -- -- -- --
40: -- -- -- -- 44 -- -- -- -- -- -- -- -- -- -- --
50: UU -- 52 -- -- -- -- -- -- -- -- -- -- -- -- --
60: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
70: -- -- -- -- -- -- -- --

$ echo lis3lv02d 0x29 > sudo tee /sys/bus/i2c/devices/i2c-0/new_device
lis3lv02d 0x29

$ sudo dmesg
[    0.000000] Linux version 6.12.28 (nixbld@localhost) (gcc (GCC) 14.2.1 20250322, GNU ld (GNU Binutils) 2.44) #1-NixOS SMP PREEMPT_DYNAMIC Fri May  9 07:50:53 UTC 2025
[...]
[    0.000000] DMI: Dell Inc. Precision 3551/07YHW8, BIOS 1.18.0 10/03/2022
[...]
[ 3749.077624] lis3lv02d_i2c 0-0029: supply Vdd not found, using dummy regulator
[ 3749.077732] lis3lv02d_i2c 0-0029: supply Vdd_IO not found, using dummy regulator
[ 3749.098674] lis3lv02d: 8 bits 3DC sensor found
[ 3749.182480] input: ST LIS3LV02DL Accelerometer as /devices/platform/lis3lv02d/input/input28
[ 3749.182899] i2c i2c-0: new_device: Instantiated device lis3lv02d at 0x29

Signed-off-by: Jan-Niklas Burfeind <kernel@aiyionpri.me>
Reviewed-by: Paul Menzel <pmenzel@molgen.mpg.de>
Link: https://lore.kernel.org/r/20250710190919.37842-1-kernel@aiyionpri.me
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
mdroth pushed a commit that referenced this pull request Oct 10, 2025
syzbot reported weird splats [0][1] in cipso_v4_sock_setattr() while
freeing inet_sk(sk)->inet_opt.

The address was freed multiple times even though it was read-only memory.

cipso_v4_sock_setattr() did nothing wrong, and the root cause was type
confusion.

The cited commit made it possible to create smc_sock as an INET socket.

The issue is that struct smc_sock does not have struct inet_sock as the
first member but hijacks AF_INET and AF_INET6 sk_family, which confuses
various places.

In this case, inet_sock.inet_opt was actually smc_sock.clcsk_data_ready(),
which is an address of a function in the text segment.

  $ pahole -C inet_sock vmlinux
  struct inet_sock {
  ...
          struct ip_options_rcu *    inet_opt;             /*   784     8 */

  $ pahole -C smc_sock vmlinux
  struct smc_sock {
  ...
          void                       (*clcsk_data_ready)(struct sock *); /*   784     8 */

The same issue for another field was reported before. [2][3]

At that time, an ugly hack was suggested [4], but it makes both INET
and SMC code error-prone and hard to change.

Also, yet another variant was fixed by a hacky commit 98d4435
("net/smc: prevent NULL pointer dereference in txopt_get").

Instead of papering over the root cause by such hacks, we should not
allow non-INET socket to reuse the INET infra.

Let's add inet_sock as the first member of smc_sock.

[0]:
kvfree_call_rcu(): Double-freed call. rcu_head 000000006921da73
WARNING: CPU: 0 PID: 6718 at mm/slab_common.c:1956 kvfree_call_rcu+0x94/0x3f0 mm/slab_common.c:1955
Modules linked in:
CPU: 0 UID: 0 PID: 6718 Comm: syz.0.17 Tainted: G        W           6.16.0-rc4-syzkaller-g7482bb149b9f #0 PREEMPT
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : kvfree_call_rcu+0x94/0x3f0 mm/slab_common.c:1955
lr : kvfree_call_rcu+0x94/0x3f0 mm/slab_common.c:1955
sp : ffff8000a03a7730
x29: ffff8000a03a7730 x28: 00000000fffffff5 x27: 1fffe000184823d3
x26: dfff800000000000 x25: ffff0000c2411e9e x24: ffff0000dd88da00
x23: ffff8000891ac9a0 x22: 00000000ffffffea x21: ffff8000891ac9a0
x20: ffff8000891ac9a0 x19: ffff80008afc2480 x18: 00000000ffffffff
x17: 0000000000000000 x16: ffff80008ae642c8 x15: ffff700011ede14c
x14: 1ffff00011ede14c x13: 0000000000000004 x12: ffffffffffffffff
x11: ffff700011ede14c x10: 0000000000ff0100 x9 : 5fa3c1ffaf0ff000
x8 : 5fa3c1ffaf0ff000 x7 : 0000000000000001 x6 : 0000000000000001
x5 : ffff8000a03a7078 x4 : ffff80008f766c20 x3 : ffff80008054d360
x2 : 0000000000000000 x1 : 0000000000000201 x0 : 0000000000000000
Call trace:
 kvfree_call_rcu+0x94/0x3f0 mm/slab_common.c:1955 (P)
 cipso_v4_sock_setattr+0x2f0/0x3f4 net/ipv4/cipso_ipv4.c:1914
 netlbl_sock_setattr+0x240/0x334 net/netlabel/netlabel_kapi.c:1000
 smack_netlbl_add+0xa8/0x158 security/smack/smack_lsm.c:2581
 smack_inode_setsecurity+0x378/0x430 security/smack/smack_lsm.c:2912
 security_inode_setsecurity+0x118/0x3c0 security/security.c:2706
 __vfs_setxattr_noperm+0x174/0x5c4 fs/xattr.c:251
 __vfs_setxattr_locked+0x1ec/0x218 fs/xattr.c:295
 vfs_setxattr+0x158/0x2ac fs/xattr.c:321
 do_setxattr fs/xattr.c:636 [inline]
 file_setxattr+0x1b8/0x294 fs/xattr.c:646
 path_setxattrat+0x2ac/0x320 fs/xattr.c:711
 __do_sys_fsetxattr fs/xattr.c:761 [inline]
 __se_sys_fsetxattr fs/xattr.c:758 [inline]
 __arm64_sys_fsetxattr+0xc0/0xdc fs/xattr.c:758
 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
 invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:49
 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:132
 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151
 el0_svc+0x58/0x180 arch/arm64/kernel/entry-common.c:879
 el0t_64_sync_handler+0x84/0x12c arch/arm64/kernel/entry-common.c:898
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600

[1]:
Unable to handle kernel write to read-only memory at virtual address ffff8000891ac9a8
KASAN: probably user-memory-access in range [0x0000000448d64d40-0x0000000448d64d47]
Mem abort info:
  ESR = 0x000000009600004e
  EC = 0x25: DABT (current EL), IL = 32 bits
  SET = 0, FnV = 0
  EA = 0, S1PTW = 0
  FSC = 0x0e: level 2 permission fault
Data abort info:
  ISV = 0, ISS = 0x0000004e, ISS2 = 0x00000000
  CM = 0, WnR = 1, TnD = 0, TagAccess = 0
  GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0
swapper pgtable: 4k pages, 48-bit VAs, pgdp=0000000207144000
[ffff8000891ac9a8] pgd=0000000000000000, p4d=100000020f950003, pud=100000020f951003, pmd=0040000201000781
Internal error: Oops: 000000009600004e [#1]  SMP
Modules linked in:
CPU: 0 UID: 0 PID: 6946 Comm: syz.0.69 Not tainted 6.16.0-rc4-syzkaller-g7482bb149b9f #0 PREEMPT
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
pstate: 604000c5 (nZCv daIF +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : kvfree_call_rcu+0x31c/0x3f0 mm/slab_common.c:1971
lr : add_ptr_to_bulk_krc_lock mm/slab_common.c:1838 [inline]
lr : kvfree_call_rcu+0xfc/0x3f0 mm/slab_common.c:1963
sp : ffff8000a28a7730
x29: ffff8000a28a7730 x28: 00000000fffffff5 x27: 1fffe00018b09bb3
x26: 0000000000000001 x25: ffff80008f66e000 x24: ffff00019beaf498
x23: ffff00019beaf4c0 x22: 0000000000000000 x21: ffff8000891ac9a0
x20: ffff8000891ac9a0 x19: 0000000000000000 x18: 00000000ffffffff
x17: ffff800093363000 x16: ffff80008052c6e4 x15: ffff700014514ecc
x14: 1ffff00014514ecc x13: 0000000000000004 x12: ffffffffffffffff
x11: ffff700014514ecc x10: 0000000000000001 x9 : 0000000000000001
x8 : ffff00019beaf7b4 x7 : ffff800080a94154 x6 : 0000000000000000
x5 : ffff8000935efa60 x4 : 0000000000000008 x3 : ffff80008052c7fc
x2 : 0000000000000001 x1 : ffff8000891ac9a0 x0 : 0000000000000001
Call trace:
 kvfree_call_rcu+0x31c/0x3f0 mm/slab_common.c:1967 (P)
 cipso_v4_sock_setattr+0x2f0/0x3f4 net/ipv4/cipso_ipv4.c:1914
 netlbl_sock_setattr+0x240/0x334 net/netlabel/netlabel_kapi.c:1000
 smack_netlbl_add+0xa8/0x158 security/smack/smack_lsm.c:2581
 smack_inode_setsecurity+0x378/0x430 security/smack/smack_lsm.c:2912
 security_inode_setsecurity+0x118/0x3c0 security/security.c:2706
 __vfs_setxattr_noperm+0x174/0x5c4 fs/xattr.c:251
 __vfs_setxattr_locked+0x1ec/0x218 fs/xattr.c:295
 vfs_setxattr+0x158/0x2ac fs/xattr.c:321
 do_setxattr fs/xattr.c:636 [inline]
 file_setxattr+0x1b8/0x294 fs/xattr.c:646
 path_setxattrat+0x2ac/0x320 fs/xattr.c:711
 __do_sys_fsetxattr fs/xattr.c:761 [inline]
 __se_sys_fsetxattr fs/xattr.c:758 [inline]
 __arm64_sys_fsetxattr+0xc0/0xdc fs/xattr.c:758
 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
 invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:49
 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:132
 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151
 el0_svc+0x58/0x180 arch/arm64/kernel/entry-common.c:879
 el0t_64_sync_handler+0x84/0x12c arch/arm64/kernel/entry-common.c:898
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600
Code: aa1f03e2 52800023 97ee1e8d b4000195 (f90006b4)

Fixes: d25a92c ("net/smc: Introduce IPPROTO_SMC")
Reported-by: syzbot+40bf00346c3fe40f90f2@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/all/686d9b50.050a0220.1ffab7.0020.GAE@google.com/
Tested-by: syzbot+40bf00346c3fe40f90f2@syzkaller.appspotmail.com
Reported-by: syzbot+f22031fad6cbe52c70e7@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/all/686da0f3.050a0220.1ffab7.0022.GAE@google.com/
Reported-by: syzbot+271fed3ed6f24600c364@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=271fed3ed6f24600c364 # [2]
Link: https://lore.kernel.org/netdev/99f284be-bf1d-4bc4-a629-77b268522fff@huawei.com/ # [3]
Link: https://lore.kernel.org/netdev/20250331081003.1503211-1-wangliang74@huawei.com/ # [4]
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: D. Wythe <alibuda@linux.alibaba.com>
Reviewed-by: Wang Liang <wangliang74@huawei.com>
Link: https://patch.msgid.link/20250711060808.2977529-1-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
mdroth pushed a commit that referenced this pull request Oct 10, 2025
The conversion from compiler assisted indexing to manual
indexing wasn't done correctly. The array is still made
up of __le16 elements so multiplying the outer index by
the element size is not what we want. Fix it up.

This causes the kernel to oops when trying to transfer any
significant amount of data over wifi:

BUG: unable to handle page fault for address: ffffc900009f5282
PGD 100000067 P4D 100000067 PUD 1000fb067 PMD 102e82067 PTE 0
Oops: Oops: 0002 [#1] SMP
CPU: 1 UID: 0 PID: 99 Comm: kworker/u8:3 Not tainted 6.15.0-rc2-cl-bisect3-00604-g6204d5130a64-dirty torvalds#78 PREEMPT
Hardware name: Dell Inc. Latitude E5400                  /0D695C, BIOS A19 06/13/2013
Workqueue: events_unbound cfg80211_wiphy_work [cfg80211]
RIP: 0010:iwl_trans_pcie_tx+0x4dd/0xe60 [iwlwifi]
Code: 00 00 66 81 fa ff 0f 0f 87 42 09 00 00 3d ff 00 00 00 0f 8f 37 09 00 00 41 c1 e0 0c 41 09 d0 48 8d 14 b6 48 c1 e2 07 48 01 ca <66> 44 89 04 57 48 8d 0c 12 83 f8 3f 0f 8e 84 01 00 00 41 8b 85 80
RSP: 0018:ffffc900001c3b50 EFLAGS: 00010206
RAX: 00000000000000c1 RBX: ffff88810b180028 RCX: 00000000000000c1
RDX: 0000000000002141 RSI: 000000000000000d RDI: ffffc900009f1000
RBP: 0000000000000002 R08: 0000000000000025 R09: ffffffffa050fa60
R10: 00000000fbdbf4bc R11: 0000000000000082 R12: ffff88810e5ade40
R13: ffff88810af81588 R14: 000000000000001a R15: ffff888100dfe0c8
FS:  0000000000000000(0000) GS:ffff8881998c3000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffc900009f5282 CR3: 0000000001e39000 CR4: 00000000000426f0
Call Trace:
 <TASK>
 ? rcu_is_watching+0xd/0x40
 ? __iwl_dbg+0xb1/0xe0 [iwlwifi]
 iwlagn_tx_skb+0x8e2/0xcb0 [iwldvm]
 iwlagn_mac_tx+0x18/0x30 [iwldvm]
 ieee80211_handle_wake_tx_queue+0x6c/0xc0 [mac80211]
 ieee80211_agg_start_txq+0x140/0x2e0 [mac80211]
 ieee80211_agg_tx_operational+0x126/0x210 [mac80211]
 ieee80211_process_addba_resp+0x27b/0x2a0 [mac80211]
 ieee80211_iface_work+0x4bd/0x4d0 [mac80211]
 ? _raw_spin_unlock_irq+0x1f/0x40
 cfg80211_wiphy_work+0x117/0x1f0 [cfg80211]
 process_one_work+0x1ee/0x570
 worker_thread+0x1c5/0x3b0
 ? bh_worker+0x240/0x240
 kthread+0x110/0x220
 ? kthread_queue_delayed_work+0x90/0x90
 ret_from_fork+0x28/0x40
 ? kthread_queue_delayed_work+0x90/0x90
 ret_from_fork_asm+0x11/0x20
 </TASK>
Modules linked in: ctr aes_generic ccm sch_fq_codel bnep xt_tcpudp xt_multiport xt_state iptable_filter iptable_nat nf_nat nf_conntrack nf_defrag_ipv4 ip_tables x_tables btusb btrtl btintel btbcm bluetooth ecdh_generic ecc libaes hid_generic usbhid hid binfmt_misc joydev mousedev snd_hda_codec_hdmi iwldvm snd_hda_codec_idt snd_hda_codec_generic mac80211 coretemp iTCO_wdt watchdog kvm_intel i2c_dev snd_hda_intel libarc4 kvm snd_intel_dspcfg sdhci_pci sdhci_uhs2 snd_hda_codec iwlwifi sdhci irqbypass cqhci snd_hwdep snd_hda_core cfg80211 firewire_ohci mmc_core psmouse snd_pcm i2c_i801 firewire_core pcspkr led_class uhci_hcd i2c_smbus tg3 crc_itu_t iosf_mbi snd_timer rfkill libphy ehci_pci snd ehci_hcd lpc_ich mfd_core usbcore video intel_agp usb_common soundcore intel_gtt evdev agpgart parport_pc wmi parport backlight
CR2: ffffc900009f5282
---[ end trace 0000000000000000 ]---
RIP: 0010:iwl_trans_pcie_tx+0x4dd/0xe60 [iwlwifi]
Code: 00 00 66 81 fa ff 0f 0f 87 42 09 00 00 3d ff 00 00 00 0f 8f 37 09 00 00 41 c1 e0 0c 41 09 d0 48 8d 14 b6 48 c1 e2 07 48 01 ca <66> 44 89 04 57 48 8d 0c 12 83 f8 3f 0f 8e 84 01 00 00 41 8b 85 80
RSP: 0018:ffffc900001c3b50 EFLAGS: 00010206
RAX: 00000000000000c1 RBX: ffff88810b180028 RCX: 00000000000000c1
RDX: 0000000000002141 RSI: 000000000000000d RDI: ffffc900009f1000
RBP: 0000000000000002 R08: 0000000000000025 R09: ffffffffa050fa60
R10: 00000000fbdbf4bc R11: 0000000000000082 R12: ffff88810e5ade40
R13: ffff88810af81588 R14: 000000000000001a R15: ffff888100dfe0c8
FS:  0000000000000000(0000) GS:ffff8881998c3000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffc900009f5282 CR3: 0000000001e39000 CR4: 00000000000426f0
Kernel panic - not syncing: Fatal exception in interrupt
Kernel Offset: disabled
---[ end Kernel panic - not syncing: Fatal exception in interrupt ]---

Cc: Miri Korenblit <miriam.rachel.korenblit@intel.com>
Fixes: 6204d51 ("wifi: iwlwifi: use bc entries instead of bc table also for pre-ax210")
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patch.msgid.link/20250711205744.28723-1-ville.syrjala@linux.intel.com
Signed-off-by: Miri Korenblit <miriam.rachel.korenblit@intel.com>
mdroth pushed a commit that referenced this pull request Oct 10, 2025
This reverts commit 7796c97.

This patch broke Dragonboard 845c (sdm845). I see:

    Unexpected kernel BRK exception at EL1
    Internal error: BRK handler: 00000000f20003e8 [#1]  SMP
    pc : qcom_swrm_set_channel_map+0x7c/0x80 [soundwire_qcom]
    lr : snd_soc_dai_set_channel_map+0x34/0x78
    Call trace:
     qcom_swrm_set_channel_map+0x7c/0x80 [soundwire_qcom] (P)
     sdm845_dai_init+0x18c/0x2e0 [snd_soc_sdm845]
     snd_soc_link_init+0x28/0x6c
     snd_soc_bind_card+0x5f4/0xb0c
     snd_soc_register_card+0x148/0x1a4
     devm_snd_soc_register_card+0x50/0xb0
     sdm845_snd_platform_probe+0x124/0x148 [snd_soc_sdm845]
     platform_probe+0x6c/0xd0
     really_probe+0xc0/0x2a4
     __driver_probe_device+0x7c/0x130
     driver_probe_device+0x40/0x118
     __device_attach_driver+0xc4/0x108
     bus_for_each_drv+0x8c/0xf0
     __device_attach+0xa4/0x198
     device_initial_probe+0x18/0x28
     bus_probe_device+0xb8/0xbc
     deferred_probe_work_func+0xac/0xfc
     process_one_work+0x244/0x658
     worker_thread+0x1b4/0x360
     kthread+0x148/0x228
     ret_from_fork+0x10/0x20
    Kernel panic - not syncing: BRK handler: Fatal exception

Dan has also reported following issues with the original patch
https://lore.kernel.org/all/33fe8fe7-719a-405a-9ed2-d9f816ce1d57@sabinyo.mountain/

Bug #1:
The zeroeth element of ctrl->pconfig[] is supposed to be unused.  We
start counting at 1.  However this code sets ctrl->pconfig[0].ch_mask = 128.

Bug #2:
There are SLIM_MAX_TX_PORTS (16) elements in tx_ch[] array but only
QCOM_SDW_MAX_PORTS + 1 (15) in the ctrl->pconfig[] array so it corrupts
memory like Yongqin Liu pointed out.

Bug 3:
Like Jie Gan pointed out, it erases all the tx information with the rx
information.

Cc: stable@vger.kernel.org # v6.15+
Signed-off-by: Amit Pundir <amit.pundir@linaro.org>
Acked-by: Srinivas Kandagatla <srini@kernel.org>
Link: https://lore.kernel.org/r/20250709174949.8541-1-amit.pundir@linaro.org
Signed-off-by: Vinod Koul <vkoul@kernel.org>
mdroth pushed a commit that referenced this pull request Oct 10, 2025
When device reset is triggered by feature changes such as toggling Rx
VLAN offload, wx->do_reset() is called to reinitialize Rx rings. The
hardware descriptor ring may retain stale values from previous sessions.
And only set the length to 0 in rx_desc[0] would result in building
malformed SKBs. Fix it to ensure a clean slate after device reset.

[  549.186435] [     C16] ------------[ cut here ]------------
[  549.186457] [     C16] kernel BUG at net/core/skbuff.c:2814!
[  549.186468] [     C16] Oops: invalid opcode: 0000 [#1] SMP NOPTI
[  549.186472] [     C16] CPU: 16 UID: 0 PID: 0 Comm: swapper/16 Kdump: loaded Not tainted 6.16.0-rc4+ torvalds#23 PREEMPT(voluntary)
[  549.186476] [     C16] Hardware name: Micro-Star International Co., Ltd. MS-7E16/X670E GAMING PLUS WIFI (MS-7E16), BIOS 1.90 12/31/2024
[  549.186478] [     C16] RIP: 0010:__pskb_pull_tail+0x3ff/0x510
[  549.186484] [     C16] Code: 06 f0 ff 4f 34 74 7b 4d 8b 8c 24 c8 00 00 00 45 8b 84 24 c0 00 00 00 e9 c8 fd ff ff 48 c7 44 24 08 00 00 00 00 e9 5e fe ff ff <0f> 0b 31 c0 e9 23 90 5b ff 41 f7 c6 ff 0f 00 00 75 bf 49 8b 06 a8
[  549.186487] [     C16] RSP: 0018:ffffb391c0640d70 EFLAGS: 00010282
[  549.186490] [     C16] RAX: 00000000fffffff2 RBX: ffff8fe7e4d40200 RCX: 00000000fffffff2
[  549.186492] [     C16] RDX: ffff8fe7c3a4bf8e RSI: 0000000000000180 RDI: ffff8fe7c3a4bf40
[  549.186494] [     C16] RBP: ffffb391c0640da8 R08: ffff8fe7c3a4c0c0 R09: 000000000000000e
[  549.186496] [     C16] R10: ffffb391c0640d88 R11: 000000000000000e R12: ffff8fe7e4d40200
[  549.186497] [     C16] R13: 00000000fffffff2 R14: ffff8fe7fa01a000 R15: 00000000fffffff2
[  549.186499] [     C16] FS:  0000000000000000(0000) GS:ffff8fef5ae40000(0000) knlGS:0000000000000000
[  549.186502] [     C16] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  549.186503] [     C16] CR2: 00007f77d81d6000 CR3: 000000051a032000 CR4: 0000000000750ef0
[  549.186505] [     C16] PKRU: 55555554
[  549.186507] [     C16] Call Trace:
[  549.186510] [     C16]  <IRQ>
[  549.186513] [     C16]  ? srso_alias_return_thunk+0x5/0xfbef5
[  549.186517] [     C16]  __skb_pad+0xc7/0xf0
[  549.186523] [     C16]  wx_clean_rx_irq+0x355/0x3b0 [libwx]
[  549.186533] [     C16]  wx_poll+0x92/0x120 [libwx]
[  549.186540] [     C16]  __napi_poll+0x28/0x190
[  549.186544] [     C16]  net_rx_action+0x301/0x3f0
[  549.186548] [     C16]  ? srso_alias_return_thunk+0x5/0xfbef5
[  549.186551] [     C16]  ? __raw_spin_lock_irqsave+0x1e/0x50
[  549.186554] [     C16]  ? srso_alias_return_thunk+0x5/0xfbef5
[  549.186557] [     C16]  ? wake_up_nohz_cpu+0x35/0x160
[  549.186559] [     C16]  ? srso_alias_return_thunk+0x5/0xfbef5
[  549.186563] [     C16]  handle_softirqs+0xf9/0x2c0
[  549.186568] [     C16]  __irq_exit_rcu+0xc7/0x130
[  549.186572] [     C16]  common_interrupt+0xb8/0xd0
[  549.186576] [     C16]  </IRQ>
[  549.186577] [     C16]  <TASK>
[  549.186579] [     C16]  asm_common_interrupt+0x22/0x40
[  549.186582] [     C16] RIP: 0010:cpuidle_enter_state+0xc2/0x420
[  549.186585] [     C16] Code: 00 00 e8 11 0e 5e ff e8 ac f0 ff ff 49 89 c5 0f 1f 44 00 00 31 ff e8 0d ed 5c ff 45 84 ff 0f 85 40 02 00 00 fb 0f 1f 44 00 00 <45> 85 f6 0f 88 84 01 00 00 49 63 d6 48 8d 04 52 48 8d 04 82 49 8d
[  549.186587] [     C16] RSP: 0018:ffffb391c0277e78 EFLAGS: 00000246
[  549.186590] [     C16] RAX: ffff8fef5ae40000 RBX: 0000000000000003 RCX: 0000000000000000
[  549.186591] [     C16] RDX: 0000007fde0faac5 RSI: ffffffff826e53f6 RDI: ffffffff826fa9b3
[  549.186593] [     C16] RBP: ffff8fe7c3a20800 R08: 0000000000000002 R09: 0000000000000000
[  549.186595] [     C16] R10: 0000000000000000 R11: 000000000000ffff R12: ffffffff82ed7a40
[  549.186596] [     C16] R13: 0000007fde0faac5 R14: 0000000000000003 R15: 0000000000000000
[  549.186601] [     C16]  ? cpuidle_enter_state+0xb3/0x420
[  549.186605] [     C16]  cpuidle_enter+0x29/0x40
[  549.186609] [     C16]  cpuidle_idle_call+0xfd/0x170
[  549.186613] [     C16]  do_idle+0x7a/0xc0
[  549.186616] [     C16]  cpu_startup_entry+0x25/0x30
[  549.186618] [     C16]  start_secondary+0x117/0x140
[  549.186623] [     C16]  common_startup_64+0x13e/0x148
[  549.186628] [     C16]  </TASK>

Fixes: 3c47e8a ("net: libwx: Support to receive packets in NAPI")
Cc: stable@vger.kernel.org
Signed-off-by: Jiawen Wu <jiawenwu@trustnetic.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20250714024755.17512-4-jiawenwu@trustnetic.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
mdroth pushed a commit that referenced this pull request Oct 10, 2025
… runtime

Assuming the "rx-vlan-filter" feature is enabled on a net device, the
8021q module will automatically add or remove VLAN 0 when the net device
is put administratively up or down, respectively. There are a couple of
problems with the above scheme.

The first problem is a memory leak that can happen if the "rx-vlan-filter"
feature is disabled while the device is running:

 # ip link add bond1 up type bond mode 0
 # ethtool -K bond1 rx-vlan-filter off
 # ip link del dev bond1

When the device is put administratively down the "rx-vlan-filter"
feature is disabled, so the 8021q module will not remove VLAN 0 and the
memory will be leaked [1].

Another problem that can happen is that the kernel can automatically
delete VLAN 0 when the device is put administratively down despite not
adding it when the device was put administratively up since during that
time the "rx-vlan-filter" feature was disabled. null-ptr-unref or
bug_on[2] will be triggered by unregister_vlan_dev() for refcount
imbalance if toggling filtering during runtime:

$ ip link add bond0 type bond mode 0
$ ip link add link bond0 name vlan0 type vlan id 0 protocol 802.1q
$ ethtool -K bond0 rx-vlan-filter off
$ ifconfig bond0 up
$ ethtool -K bond0 rx-vlan-filter on
$ ifconfig bond0 down
$ ip link del vlan0

Root cause is as below:
step1: add vlan0 for real_dev, such as bond, team.
register_vlan_dev
    vlan_vid_add(real_dev,htons(ETH_P_8021Q),0) //refcnt=1
step2: disable vlan filter feature and enable real_dev
step3: change filter from 0 to 1
vlan_device_event
    vlan_filter_push_vids
        ndo_vlan_rx_add_vid //No refcnt added to real_dev vlan0
step4: real_dev down
vlan_device_event
    vlan_vid_del(dev, htons(ETH_P_8021Q), 0); //refcnt=0
        vlan_info_rcu_free //free vlan0
step5: delete vlan0
unregister_vlan_dev
    BUG_ON(!vlan_info); //vlan_info is null

Fix both problems by noting in the VLAN info whether VLAN 0 was
automatically added upon NETDEV_UP and based on that decide whether it
should be deleted upon NETDEV_DOWN, regardless of the state of the
"rx-vlan-filter" feature.

[1]
unreferenced object 0xffff8880068e3100 (size 256):
  comm "ip", pid 384, jiffies 4296130254
  hex dump (first 32 bytes):
    00 20 30 0d 80 88 ff ff 00 00 00 00 00 00 00 00  . 0.............
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace (crc 81ce31fa):
    __kmalloc_cache_noprof+0x2b5/0x340
    vlan_vid_add+0x434/0x940
    vlan_device_event.cold+0x75/0xa8
    notifier_call_chain+0xca/0x150
    __dev_notify_flags+0xe3/0x250
    rtnl_configure_link+0x193/0x260
    rtnl_newlink_create+0x383/0x8e0
    __rtnl_newlink+0x22c/0xa40
    rtnl_newlink+0x627/0xb00
    rtnetlink_rcv_msg+0x6fb/0xb70
    netlink_rcv_skb+0x11f/0x350
    netlink_unicast+0x426/0x710
    netlink_sendmsg+0x75a/0xc20
    __sock_sendmsg+0xc1/0x150
    ____sys_sendmsg+0x5aa/0x7b0
    ___sys_sendmsg+0xfc/0x180

[2]
kernel BUG at net/8021q/vlan.c:99!
Oops: invalid opcode: 0000 [#1] SMP KASAN PTI
CPU: 0 UID: 0 PID: 382 Comm: ip Not tainted 6.16.0-rc3 torvalds#61 PREEMPT(voluntary)
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996),
BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
RIP: 0010:unregister_vlan_dev (net/8021q/vlan.c:99 (discriminator 1))
RSP: 0018:ffff88810badf310 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffff88810da84000 RCX: ffffffffb47ceb9a
RDX: dffffc0000000000 RSI: 0000000000000008 RDI: ffff88810e8b43c8
RBP: 0000000000000000 R08: 0000000000000000 R09: fffffbfff6cefe80
R10: ffffffffb677f407 R11: ffff88810badf3c0 R12: ffff88810e8b4000
R13: 0000000000000000 R14: ffff88810642a5c0 R15: 000000000000017e
FS:  00007f1ff68c20c0(0000) GS:ffff888163a24000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f1ff5dad240 CR3: 0000000107e56000 CR4: 00000000000006f0
Call Trace:
 <TASK>
rtnl_dellink (net/core/rtnetlink.c:3511 net/core/rtnetlink.c:3553)
rtnetlink_rcv_msg (net/core/rtnetlink.c:6945)
netlink_rcv_skb (net/netlink/af_netlink.c:2535)
netlink_unicast (net/netlink/af_netlink.c:1314 net/netlink/af_netlink.c:1339)
netlink_sendmsg (net/netlink/af_netlink.c:1883)
____sys_sendmsg (net/socket.c:712 net/socket.c:727 net/socket.c:2566)
___sys_sendmsg (net/socket.c:2622)
__sys_sendmsg (net/socket.c:2652)
do_syscall_64 (arch/x86/entry/syscall_64.c:63 arch/x86/entry/syscall_64.c:94)

Fixes: ad1afb0 ("vlan_dev: VLAN 0 should be treated as "no vlan tag" (802.1p packet)")
Reported-by: syzbot+a8b046e462915c65b10b@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=a8b046e462915c65b10b
Suggested-by: Ido Schimmel <idosch@idosch.org>
Signed-off-by: Dong Chenchen <dongchenchen2@huawei.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/20250716034504.2285203-2-dongchenchen2@huawei.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
mdroth pushed a commit that referenced this pull request Oct 10, 2025
We have observed kernel panics when using timerlat with stack saving,
with the following dmesg output:

memcpy: detected buffer overflow: 88 byte write of buffer size 0
WARNING: CPU: 2 PID: 8153 at lib/string_helpers.c:1032 __fortify_report+0x55/0xa0
CPU: 2 UID: 0 PID: 8153 Comm: timerlatu/2 Kdump: loaded Not tainted 6.15.3-200.fc42.x86_64 #1 PREEMPT(lazy)
Call Trace:
 <TASK>
 ? trace_buffer_lock_reserve+0x2a/0x60
 __fortify_panic+0xd/0xf
 __timerlat_dump_stack.cold+0xd/0xd
 timerlat_dump_stack.part.0+0x47/0x80
 timerlat_fd_read+0x36d/0x390
 vfs_read+0xe2/0x390
 ? syscall_exit_to_user_mode+0x1d5/0x210
 ksys_read+0x73/0xe0
 do_syscall_64+0x7b/0x160
 ? exc_page_fault+0x7e/0x1a0
 entry_SYSCALL_64_after_hwframe+0x76/0x7e

__timerlat_dump_stack() constructs the ftrace stack entry like this:

struct stack_entry *entry;
...
memcpy(&entry->caller, fstack->calls, size);
entry->size = fstack->nr_entries;

Since commit e7186af ("tracing: Add back FORTIFY_SOURCE logic to
kernel_stack event structure"), struct stack_entry marks its caller
field with __counted_by(size). At the time of the memcpy, entry->size
contains garbage from the ringbuffer, which under some circumstances is
zero, triggering a kernel panic by buffer overflow.

Populate the size field before the memcpy so that the out-of-bounds
check knows the correct size. This is analogous to
__ftrace_trace_stack().

Cc: stable@vger.kernel.org
Cc: John Kacur <jkacur@redhat.com>
Cc: Luis Goncalves <lgoncalv@redhat.com>
Cc: Attila Fazekas <afazekas@redhat.com>
Link: https://lore.kernel.org/20250716143601.7313-1-tglozar@redhat.com
Fixes: e7186af ("tracing: Add back FORTIFY_SOURCE logic to kernel_stack event structure")
Signed-off-by: Tomas Glozar <tglozar@redhat.com>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
mdroth pushed a commit that referenced this pull request Oct 10, 2025
Sometimes the netdev triggers causes tasks to get blocked for more then
120 seconds, which in turn makes the (WAN) network port on the NanoPi
R5S fail to come up.
This results in the following (partial) trace:

  INFO: task kworker/0:1:11 blocked for more than 120 seconds.
        Not tainted 6.16-rc6+unreleased-arm64-cknow #1 Debian 6.16~rc6-1~exp1
  "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
  task:kworker/0:1     state:D stack:0     pid:11    tgid:11    ppid:2      task_flags:0x4208060 flags:0x00000010
  Workqueue: events_power_efficient reg_check_chans_work [cfg80211]
  Call trace:
   __switch_to+0xf8/0x168 (T)
   __schedule+0x3f8/0xda8
   schedule+0x3c/0x120
   schedule_preempt_disabled+0x2c/0x58
   __mutex_lock.constprop.0+0x4d0/0xab8
   __mutex_lock_slowpath+0x1c/0x30
   mutex_lock+0x50/0x68
   rtnl_lock+0x20/0x38
   reg_check_chans_work+0x40/0x478 [cfg80211]
   process_one_work+0x178/0x3e0
   worker_thread+0x260/0x390
   kthread+0x150/0x250
   ret_from_fork+0x10/0x20
  INFO: task kworker/0:1:11 is blocked on a mutex likely owned by task dhcpcd:615.
  task:dhcpcd          state:D stack:0     pid:615   tgid:615   ppid:614    task_flags:0x400140 flags:0x00000018
  Call trace:
   __switch_to+0xf8/0x168 (T)
   __schedule+0x3f8/0xda8
   schedule+0x3c/0x120
   schedule_preempt_disabled+0x2c/0x58
   rwsem_down_write_slowpath+0x1e4/0x750
   down_write+0x98/0xb0
   led_trigger_register+0x134/0x1c0
   phy_led_triggers_register+0xf4/0x258 [libphy]
   phy_attach_direct+0x30c/0x390 [libphy]
   phylink_fwnode_phy_connect+0xb0/0x138 [phylink]
   __stmmac_open+0xec/0x520 [stmmac]
   stmmac_open+0x4c/0xe8 [stmmac]
   __dev_open+0x130/0x2e0
   __dev_change_flags+0x1c4/0x248
   netif_change_flags+0x2c/0x80
   dev_change_flags+0x88/0xc8
   devinet_ioctl+0x35c/0x610
   inet_ioctl+0x204/0x260
   sock_do_ioctl+0x6c/0x140
   sock_ioctl+0x2e4/0x388
   __arm64_sys_ioctl+0xb4/0x120
   invoke_syscall+0x6c/0x100
   el0_svc_common.constprop.0+0x48/0xf0
   do_el0_svc+0x24/0x38
   el0_svc+0x3c/0x188
   el0t_64_sync_handler+0x10c/0x140
   el0t_64_sync+0x198/0x1a0

In order to not introduce a regression with kernel 6.16, drop the netdev
triggers for now while the problem is being investigated further.

Fixes: 1631cbd ("arm64: dts: rockchip: Improve LED config for NanoPi R5S")
Helped-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Diederik de Haas <didi.debian@cknow.org>
Link: https://lore.kernel.org/r/20250722123628.25660-1-didi.debian@cknow.org
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
mdroth pushed a commit that referenced this pull request Oct 10, 2025
syzbot reported a bug in in afs_put_vlserverlist.

  kAFS: bad VL server IP address
  BUG: unable to handle page fault for address: fffffffffffffffa
  ...
  Oops: Oops: 0002 [#1] SMP KASAN PTI
  ...
  RIP: 0010:refcount_dec_and_test include/linux/refcount.h:450 [inline]
  RIP: 0010:afs_put_vlserverlist+0x3a/0x220 fs/afs/vl_list.c:67
  ...
  Call Trace:
   <TASK>
   afs_alloc_cell fs/afs/cell.c:218 [inline]
   afs_lookup_cell+0x12a5/0x1680 fs/afs/cell.c:264
   afs_cell_init+0x17a/0x380 fs/afs/cell.c:386
   afs_proc_rootcell_write+0x21f/0x290 fs/afs/proc.c:247
   proc_simple_write+0x114/0x1b0 fs/proc/generic.c:825
   pde_write fs/proc/inode.c:330 [inline]
   proc_reg_write+0x23d/0x330 fs/proc/inode.c:342
   vfs_write+0x25c/0x1180 fs/read_write.c:682
   ksys_write+0x12a/0x240 fs/read_write.c:736
   do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
   do_syscall_64+0xcd/0x260 arch/x86/entry/syscall_64.c:94
   entry_SYSCALL_64_after_hwframe+0x77/0x7f

Because afs_parse_text_addrs() parses incorrectly, its return value -EINVAL
is assigned to vllist, which results in -EINVAL being used as the vllist
address when afs_put_vlserverlist() is executed.

Set the vllist value to NULL when a parsing error occurs to avoid this
issue.

Fixes: e2c2cb8 ("afs: Simplify cell record handling")
Reported-by: syzbot+5c042fbab0b292c98fc6@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=5c042fbab0b292c98fc6
Tested-by: syzbot+5c042fbab0b292c98fc6@syzkaller.appspotmail.com
Signed-off-by: Edward Adam Davis <eadavis@qq.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Link: https://lore.kernel.org/4119365.1753108011@warthog.procyon.org.uk
cc: Marc Dionne <marc.dionne@auristor.com>
cc: linux-afs@lists.infradead.org
cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
mdroth pushed a commit that referenced this pull request Dec 15, 2025
With CONFIG_PROVE_RCU_LIST=y and by executing

  $ netcat -l --sctp &
  $ netcat --sctp localhost &
  $ ss --sctp

one can trigger the following Lockdep-RCU splat(s):

  WARNING: suspicious RCU usage
  6.18.0-rc1-00093-g7f864458e9a6 #5 Not tainted
  -----------------------------
  net/sctp/diag.c:76 RCU-list traversed in non-reader section!!

  other info that might help us debug this:

  rcu_scheduler_active = 2, debug_locks = 1
  2 locks held by ss/215:
   #0: ffff9c740828bec0 (nlk_cb_mutex-SOCK_DIAG){+.+.}-{4:4}, at: __netlink_dump_start+0x84/0x2b0
   #1: ffff9c7401d72cd0 (sk_lock-AF_INET6){+.+.}-{0:0}, at: sctp_sock_dump+0x38/0x200

  stack backtrace:
  CPU: 0 UID: 0 PID: 215 Comm: ss Not tainted 6.18.0-rc1-00093-g7f864458e9a6 #5 PREEMPT(voluntary)
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
  Call Trace:
   <TASK>
   dump_stack_lvl+0x5d/0x90
   lockdep_rcu_suspicious.cold+0x4e/0xa3
   inet_sctp_diag_fill.isra.0+0x4b1/0x5d0
   sctp_sock_dump+0x131/0x200
   sctp_transport_traverse_process+0x170/0x1b0
   ? __pfx_sctp_sock_filter+0x10/0x10
   ? __pfx_sctp_sock_dump+0x10/0x10
   sctp_diag_dump+0x103/0x140
   __inet_diag_dump+0x70/0xb0
   netlink_dump+0x148/0x490
   __netlink_dump_start+0x1f3/0x2b0
   inet_diag_handler_cmd+0xcd/0x100
   ? __pfx_inet_diag_dump_start+0x10/0x10
   ? __pfx_inet_diag_dump+0x10/0x10
   ? __pfx_inet_diag_dump_done+0x10/0x10
   sock_diag_rcv_msg+0x18e/0x320
   ? __pfx_sock_diag_rcv_msg+0x10/0x10
   netlink_rcv_skb+0x4d/0x100
   netlink_unicast+0x1d7/0x2b0
   netlink_sendmsg+0x203/0x450
   ____sys_sendmsg+0x30c/0x340
   ___sys_sendmsg+0x94/0xf0
   __sys_sendmsg+0x83/0xf0
   do_syscall_64+0xbb/0x390
   entry_SYSCALL_64_after_hwframe+0x77/0x7f
   ...
   </TASK>

Fixes: 8f840e4 ("sctp: add the sctp_diag.c file")
Signed-off-by: Stefan Wiehler <stefan.wiehler@nokia.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Acked-by: Xin Long <lucien.xin@gmail.com>
Link: https://patch.msgid.link/20251028161506.3294376-2-stefan.wiehler@nokia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
mdroth pushed a commit that referenced this pull request Dec 15, 2025
Raw IP packets have no MAC header, leaving skb->mac_header uninitialized.
This can trigger kernel panics on ARM64 when xfrm or other subsystems
access the offset due to strict alignment checks.

Initialize the MAC header to prevent such crashes.

This can trigger kernel panics on ARM when running IPsec over the
qmimux0 interface.

Example trace:

    Internal error: Oops: 000000009600004f [#1] SMP
    CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted 6.12.34-gbe78e49cb433 #1
    Hardware name: LS1028A RDB Board (DT)
    pstate: 60000005 (nZCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
    pc : xfrm_input+0xde8/0x1318
    lr : xfrm_input+0x61c/0x1318
    sp : ffff800080003b20
    Call trace:
     xfrm_input+0xde8/0x1318
     xfrm6_rcv+0x38/0x44
     xfrm6_esp_rcv+0x48/0xa8
     ip6_protocol_deliver_rcu+0x94/0x4b0
     ip6_input_finish+0x44/0x70
     ip6_input+0x44/0xc0
     ipv6_rcv+0x6c/0x114
     __netif_receive_skb_one_core+0x5c/0x8c
     __netif_receive_skb+0x18/0x60
     process_backlog+0x78/0x17c
     __napi_poll+0x38/0x180
     net_rx_action+0x168/0x2f0

Fixes: c6adf77 ("net: usb: qmi_wwan: add qmap mux protocol support")
Signed-off-by: Qendrim Maxhuni <qendrim.maxhuni@garderos.com>
Link: https://patch.msgid.link/20251029075744.105113-1-qendrim.maxhuni@garderos.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
mdroth pushed a commit that referenced this pull request Dec 15, 2025
Michael Chan says:

====================
bnxt_en: Bug fixes

Patches 1, 3, and 4 are bug fixes related to the FW log tracing driver
coredump feature recently added in 6.13.  Patch #1 adds the necessary
call to shutdown the FW logging DMA during PCI shutdown.  Patch #3 fixes
a possible null pointer derefernce when using early versions of the FW
with this feature.  Patch #4 adds the coredump header information
unconditionally to make it more robust.

Patch #2 fixes a possible memory leak during PTP shutdown.  Patch #5
eliminates a dmesg warning when doing devlink reload.
====================

Link: https://patch.msgid.link/20251104005700.542174-1-michael.chan@broadcom.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
mdroth pushed a commit that referenced this pull request Dec 15, 2025
… NULL on error

Make knav_dma_open_channel consistently return NULL on error instead
of ERR_PTR. Currently the header include/linux/soc/ti/knav_dma.h
returns NULL when the driver is disabled, but the driver
implementation does not even return NULL or ERR_PTR on failure,
causing inconsistency in the users. This results in a crash in
netcp_free_navigator_resources as followed (trimmed):

Unhandled fault: alignment exception (0x221) at 0xfffffff2
[fffffff2] *pgd=80000800207003, *pmd=82ffda003, *pte=00000000
Internal error: : 221 [#1] SMP ARM
Modules linked in:
CPU: 0 UID: 0 PID: 1 Comm: swapper/0 Not tainted 6.17.0-rc7 #1 NONE
Hardware name: Keystone
PC is at knav_dma_close_channel+0x30/0x19c
LR is at netcp_free_navigator_resources+0x2c/0x28c

[... TRIM...]

Call trace:
 knav_dma_close_channel from netcp_free_navigator_resources+0x2c/0x28c
 netcp_free_navigator_resources from netcp_ndo_open+0x430/0x46c
 netcp_ndo_open from __dev_open+0x114/0x29c
 __dev_open from __dev_change_flags+0x190/0x208
 __dev_change_flags from netif_change_flags+0x1c/0x58
 netif_change_flags from dev_change_flags+0x38/0xa0
 dev_change_flags from ip_auto_config+0x2c4/0x11f0
 ip_auto_config from do_one_initcall+0x58/0x200
 do_one_initcall from kernel_init_freeable+0x1cc/0x238
 kernel_init_freeable from kernel_init+0x1c/0x12c
 kernel_init from ret_from_fork+0x14/0x38
[... TRIM...]

Standardize the error handling by making the function return NULL on
all error conditions. The API is used in just the netcp_core.c so the
impact is limited.

Note, this change, in effect reverts commit 5b6cb43 ("net:
ethernet: ti: netcp_core: return error while dma channel open issue"),
but provides a less error prone implementation.

Suggested-by: Simon Horman <horms@kernel.org>
Suggested-by: Jacob Keller <jacob.e.keller@intel.com>
Signed-off-by: Nishanth Menon <nm@ti.com>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Link: https://patch.msgid.link/20251103162811.3730055-1-nm@ti.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
mdroth pushed a commit that referenced this pull request Dec 15, 2025
I started seeing this in recent Fedora 42 kernels:

  root@x1:~# uname -a
  Linux x1 6.17.4-200.fc42.x86_64 #1 SMP PREEMPT_DYNAMIC Sun Oct 19 18:47:49 UTC 2025 x86_64 GNU/Linux
  root@x1:~#

  root@x1:~# perf test 1
    1: vmlinux symtab matches kallsyms     : FAILED!
  root@x1:~#

Related to:

  root@x1:~# grep ' 1 ' /proc/kallsyms
  ffffffffb098bc00 1 __pfx__RNCINvNtNtNtCsfwaGRd4cjqE_4core4iter8adapters3map12map_try_foldjNtCskFudTml27HW_12drm_panic_qr7VersionuINtNtNtBa_3ops12control_flow11ControlFlowB10_ENcB10_0NCINvNvNtNtNtB8_6traits8iterator8Iterator4find5checkB10_NCNvMB12_B10_13from_segments0E0E0B12_
  ffffffffb098bc10 1 _RNCINvNtNtNtCsfwaGRd4cjqE_4core4iter8adapters3map12map_try_foldjNtCskFudTml27HW_12drm_panic_qr7VersionuINtNtNtBa_3ops12control_flow11ControlFlowB10_ENcB10_0NCINvNvNtNtNtB8_6traits8iterator8Iterator4find5checkB10_NCNvMB12_B10_13from_segments0E0E0B12_
  root@x1:~#

That is found in:

  root@x1:~# pahole --running_kernel_vmlinux
  /usr/lib/debug/lib/modules/6.17.4-200.fc42.x86_64/vmlinux
  root@x1:~#

  root@x1:~# readelf -sW /usr/lib/debug/lib/modules/6.17.4-200.fc42.x86_64/vmlinux | grep __pfx__RNCINvNtNtNtCsfwaGRd4cjqE_4core4iter8adapters3map12map_try_foldjNtCskFudTml27HW_12drm_panic_qr7VersionuINtNtNtBa_3ops12control_flow11ControlFlowB10_ENcB10_0NCINvNvNtNtNtB8_6traits8iterator8Iterator4find5checkB10_NCNvMB12_B10_13from_segments0E0E0B12_
  150649: ffffffff81f8bc00    16 FUNC    LOCAL  DEFAULT    1 __pfx__RNCINvNtNtNtCsfwaGRd4cjqE_4core4iter8adapters3map12map_try_foldjNtCskFudTml27HW_12drm_panic_qr7VersionuINtNtNtBa_3ops12control_flow11ControlFlowB10_ENcB10_0NCINvNvNtNtNtB8_6traits8iterator8Iterator4find5checkB10_NCNvMB12_B10_13from_segments0E0E0B12_
  root@x1:~#

But was being filtered out when reading /proc/kallsyms, as the '1'
symbol type was not being handled, do it, there are just two of them at
this point.

Cc: Alex Gaynor <alex.gaynor@gmail.com>
Cc: Alice Ryhl <aliceryhl@google.com>
Cc: Andreas Hindborg <a.hindborg@kernel.org>
Cc: Benno Lossin <lossin@kernel.org>
Cc: Björn Roy Baron <bjorn3_gh@protonmail.com>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Danilo Krummrich <dakr@kernel.org>
Cc: Gary Guo <gary@garyguo.net>
Cc: Miguel Ojeda <ojeda@kernel.org>
Cc: Trevor Gross <tmgross@umich.edu>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
mdroth pushed a commit that referenced this pull request Dec 15, 2025
On completion of i915_vma_pin_ww(), a synchronous variant of
dma_fence_work_commit() is called.  When pinning a VMA to GGTT address
space on a Cherry View family processor, or on a Broxton generation SoC
with VTD enabled, i.e., when stop_machine() is then called from
intel_ggtt_bind_vma(), that can potentially lead to lock inversion among
reservation_ww and cpu_hotplug locks.

[86.861179] ======================================================
[86.861193] WARNING: possible circular locking dependency detected
[86.861209] 6.15.0-rc5-CI_DRM_16515-gca0305cadc2d+ #1 Tainted: G     U
[86.861226] ------------------------------------------------------
[86.861238] i915_module_loa/1432 is trying to acquire lock:
[86.861252] ffffffff83489090 (cpu_hotplug_lock){++++}-{0:0}, at: stop_machine+0x1c/0x50
[86.861290]
but task is already holding lock:
[86.861303] ffffc90002e0b4c8 (reservation_ww_class_mutex){+.+.}-{3:3}, at: i915_vma_pin.constprop.0+0x39/0x1d0 [i915]
[86.862233]
which lock already depends on the new lock.
[86.862251]
the existing dependency chain (in reverse order) is:
[86.862265]
-> #5 (reservation_ww_class_mutex){+.+.}-{3:3}:
[86.862292]        dma_resv_lockdep+0x19a/0x390
[86.862315]        do_one_initcall+0x60/0x3f0
[86.862334]        kernel_init_freeable+0x3cd/0x680
[86.862353]        kernel_init+0x1b/0x200
[86.862369]        ret_from_fork+0x47/0x70
[86.862383]        ret_from_fork_asm+0x1a/0x30
[86.862399]
-> #4 (reservation_ww_class_acquire){+.+.}-{0:0}:
[86.862425]        dma_resv_lockdep+0x178/0x390
[86.862440]        do_one_initcall+0x60/0x3f0
[86.862454]        kernel_init_freeable+0x3cd/0x680
[86.862470]        kernel_init+0x1b/0x200
[86.862482]        ret_from_fork+0x47/0x70
[86.862495]        ret_from_fork_asm+0x1a/0x30
[86.862509]
-> #3 (&mm->mmap_lock){++++}-{3:3}:
[86.862531]        down_read_killable+0x46/0x1e0
[86.862546]        lock_mm_and_find_vma+0xa2/0x280
[86.862561]        do_user_addr_fault+0x266/0x8e0
[86.862578]        exc_page_fault+0x8a/0x2f0
[86.862593]        asm_exc_page_fault+0x27/0x30
[86.862607]        filldir64+0xeb/0x180
[86.862620]        kernfs_fop_readdir+0x118/0x480
[86.862635]        iterate_dir+0xcf/0x2b0
[86.862648]        __x64_sys_getdents64+0x84/0x140
[86.862661]        x64_sys_call+0x1058/0x2660
[86.862675]        do_syscall_64+0x91/0xe90
[86.862689]        entry_SYSCALL_64_after_hwframe+0x76/0x7e
[86.862703]
-> #2 (&root->kernfs_rwsem){++++}-{3:3}:
[86.862725]        down_write+0x3e/0xf0
[86.862738]        kernfs_add_one+0x30/0x3c0
[86.862751]        kernfs_create_dir_ns+0x53/0xb0
[86.862765]        internal_create_group+0x134/0x4c0
[86.862779]        sysfs_create_group+0x13/0x20
[86.862792]        topology_add_dev+0x1d/0x30
[86.862806]        cpuhp_invoke_callback+0x4b5/0x850
[86.862822]        cpuhp_issue_call+0xbf/0x1f0
[86.862836]        __cpuhp_setup_state_cpuslocked+0x111/0x320
[86.862852]        __cpuhp_setup_state+0xb0/0x220
[86.862866]        topology_sysfs_init+0x30/0x50
[86.862879]        do_one_initcall+0x60/0x3f0
[86.862893]        kernel_init_freeable+0x3cd/0x680
[86.862908]        kernel_init+0x1b/0x200
[86.862921]        ret_from_fork+0x47/0x70
[86.862934]        ret_from_fork_asm+0x1a/0x30
[86.862947]
-> #1 (cpuhp_state_mutex){+.+.}-{3:3}:
[86.862969]        __mutex_lock+0xaa/0xed0
[86.862982]        mutex_lock_nested+0x1b/0x30
[86.862995]        __cpuhp_setup_state_cpuslocked+0x67/0x320
[86.863012]        __cpuhp_setup_state+0xb0/0x220
[86.863026]        page_alloc_init_cpuhp+0x2d/0x60
[86.863041]        mm_core_init+0x22/0x2d0
[86.863054]        start_kernel+0x576/0xbd0
[86.863068]        x86_64_start_reservations+0x18/0x30
[86.863084]        x86_64_start_kernel+0xbf/0x110
[86.863098]        common_startup_64+0x13e/0x141
[86.863114]
-> #0 (cpu_hotplug_lock){++++}-{0:0}:
[86.863135]        __lock_acquire+0x1635/0x2810
[86.863152]        lock_acquire+0xc4/0x2f0
[86.863166]        cpus_read_lock+0x41/0x100
[86.863180]        stop_machine+0x1c/0x50
[86.863194]        bxt_vtd_ggtt_insert_entries__BKL+0x3b/0x60 [i915]
[86.863987]        intel_ggtt_bind_vma+0x43/0x70 [i915]
[86.864735]        __vma_bind+0x55/0x70 [i915]
[86.865510]        fence_work+0x26/0xa0 [i915]
[86.866248]        fence_notify+0xa1/0x140 [i915]
[86.866983]        __i915_sw_fence_complete+0x8f/0x270 [i915]
[86.867719]        i915_sw_fence_commit+0x39/0x60 [i915]
[86.868453]        i915_vma_pin_ww+0x462/0x1360 [i915]
[86.869228]        i915_vma_pin.constprop.0+0x133/0x1d0 [i915]
[86.870001]        initial_plane_vma+0x307/0x840 [i915]
[86.870774]        intel_initial_plane_config+0x33f/0x670 [i915]
[86.871546]        intel_display_driver_probe_nogem+0x1c6/0x260 [i915]
[86.872330]        i915_driver_probe+0x7fa/0xe80 [i915]
[86.873057]        i915_pci_probe+0xe6/0x220 [i915]
[86.873782]        local_pci_probe+0x47/0xb0
[86.873802]        pci_device_probe+0xf3/0x260
[86.873817]        really_probe+0xf1/0x3c0
[86.873833]        __driver_probe_device+0x8c/0x180
[86.873848]        driver_probe_device+0x24/0xd0
[86.873862]        __driver_attach+0x10f/0x220
[86.873876]        bus_for_each_dev+0x7f/0xe0
[86.873892]        driver_attach+0x1e/0x30
[86.873904]        bus_add_driver+0x151/0x290
[86.873917]        driver_register+0x5e/0x130
[86.873931]        __pci_register_driver+0x7d/0x90
[86.873945]        i915_pci_register_driver+0x23/0x30 [i915]
[86.874678]        i915_init+0x37/0x120 [i915]
[86.875347]        do_one_initcall+0x60/0x3f0
[86.875369]        do_init_module+0x97/0x2a0
[86.875385]        load_module+0x2c54/0x2d80
[86.875398]        init_module_from_file+0x96/0xe0
[86.875413]        idempotent_init_module+0x117/0x330
[86.875426]        __x64_sys_finit_module+0x77/0x100
[86.875440]        x64_sys_call+0x24de/0x2660
[86.875454]        do_syscall_64+0x91/0xe90
[86.875470]        entry_SYSCALL_64_after_hwframe+0x76/0x7e
[86.875486]
other info that might help us debug this:
[86.875502] Chain exists of:
  cpu_hotplug_lock --> reservation_ww_class_acquire --> reservation_ww_class_mutex
[86.875539]  Possible unsafe locking scenario:
[86.875552]        CPU0                    CPU1
[86.875563]        ----                    ----
[86.875573]   lock(reservation_ww_class_mutex);
[86.875588]                                lock(reservation_ww_class_acquire);
[86.875606]                                lock(reservation_ww_class_mutex);
[86.875624]   rlock(cpu_hotplug_lock);
[86.875637]
 *** DEADLOCK ***
[86.875650] 3 locks held by i915_module_loa/1432:
[86.875663]  #0: ffff888101f5c1b0 (&dev->mutex){....}-{3:3}, at: __driver_attach+0x104/0x220
[86.875699]  #1: ffffc90002e0b4a0 (reservation_ww_class_acquire){+.+.}-{0:0}, at: i915_vma_pin.constprop.0+0x39/0x1d0 [i915]
[86.876512]  #2: ffffc90002e0b4c8 (reservation_ww_class_mutex){+.+.}-{3:3}, at: i915_vma_pin.constprop.0+0x39/0x1d0 [i915]
[86.877305]
stack backtrace:
[86.877326] CPU: 0 UID: 0 PID: 1432 Comm: i915_module_loa Tainted: G     U              6.15.0-rc5-CI_DRM_16515-gca0305cadc2d+ #1 PREEMPT(voluntary)
[86.877334] Tainted: [U]=USER
[86.877336] Hardware name:  /NUC5CPYB, BIOS PYBSWCEL.86A.0079.2020.0420.1316 04/20/2020
[86.877339] Call Trace:
[86.877344]  <TASK>
[86.877353]  dump_stack_lvl+0x91/0xf0
[86.877364]  dump_stack+0x10/0x20
[86.877369]  print_circular_bug+0x285/0x360
[86.877379]  check_noncircular+0x135/0x150
[86.877390]  __lock_acquire+0x1635/0x2810
[86.877403]  lock_acquire+0xc4/0x2f0
[86.877408]  ? stop_machine+0x1c/0x50
[86.877422]  ? __pfx_bxt_vtd_ggtt_insert_entries__cb+0x10/0x10 [i915]
[86.878173]  cpus_read_lock+0x41/0x100
[86.878182]  ? stop_machine+0x1c/0x50
[86.878191]  ? __pfx_bxt_vtd_ggtt_insert_entries__cb+0x10/0x10 [i915]
[86.878916]  stop_machine+0x1c/0x50
[86.878927]  bxt_vtd_ggtt_insert_entries__BKL+0x3b/0x60 [i915]
[86.879652]  intel_ggtt_bind_vma+0x43/0x70 [i915]
[86.880375]  __vma_bind+0x55/0x70 [i915]
[86.881133]  fence_work+0x26/0xa0 [i915]
[86.881851]  fence_notify+0xa1/0x140 [i915]
[86.882566]  __i915_sw_fence_complete+0x8f/0x270 [i915]
[86.883286]  i915_sw_fence_commit+0x39/0x60 [i915]
[86.884003]  i915_vma_pin_ww+0x462/0x1360 [i915]
[86.884756]  ? i915_vma_pin.constprop.0+0x6c/0x1d0 [i915]
[86.885513]  i915_vma_pin.constprop.0+0x133/0x1d0 [i915]
[86.886281]  initial_plane_vma+0x307/0x840 [i915]
[86.887049]  intel_initial_plane_config+0x33f/0x670 [i915]
[86.887819]  intel_display_driver_probe_nogem+0x1c6/0x260 [i915]
[86.888587]  i915_driver_probe+0x7fa/0xe80 [i915]
[86.889293]  ? mutex_unlock+0x12/0x20
[86.889301]  ? drm_privacy_screen_get+0x171/0x190
[86.889308]  ? acpi_dev_found+0x66/0x80
[86.889321]  i915_pci_probe+0xe6/0x220 [i915]
[86.890038]  local_pci_probe+0x47/0xb0
[86.890049]  pci_device_probe+0xf3/0x260
[86.890058]  really_probe+0xf1/0x3c0
[86.890067]  __driver_probe_device+0x8c/0x180
[86.890072]  driver_probe_device+0x24/0xd0
[86.890078]  __driver_attach+0x10f/0x220
[86.890083]  ? __pfx___driver_attach+0x10/0x10
[86.890088]  bus_for_each_dev+0x7f/0xe0
[86.890097]  driver_attach+0x1e/0x30
[86.890101]  bus_add_driver+0x151/0x290
[86.890107]  driver_register+0x5e/0x130
[86.890113]  __pci_register_driver+0x7d/0x90
[86.890119]  i915_pci_register_driver+0x23/0x30 [i915]
[86.890833]  i915_init+0x37/0x120 [i915]
[86.891482]  ? __pfx_i915_init+0x10/0x10 [i915]
[86.892135]  do_one_initcall+0x60/0x3f0
[86.892145]  ? __kmalloc_cache_noprof+0x33f/0x470
[86.892157]  do_init_module+0x97/0x2a0
[86.892164]  load_module+0x2c54/0x2d80
[86.892168]  ? __kernel_read+0x15c/0x300
[86.892185]  ? kernel_read_file+0x2b1/0x320
[86.892195]  init_module_from_file+0x96/0xe0
[86.892199]  ? init_module_from_file+0x96/0xe0
[86.892211]  idempotent_init_module+0x117/0x330
[86.892224]  __x64_sys_finit_module+0x77/0x100
[86.892230]  x64_sys_call+0x24de/0x2660
[86.892236]  do_syscall_64+0x91/0xe90
[86.892243]  ? irqentry_exit+0x77/0xb0
[86.892249]  ? sysvec_apic_timer_interrupt+0x57/0xc0
[86.892256]  entry_SYSCALL_64_after_hwframe+0x76/0x7e
[86.892261] RIP: 0033:0x7303e1b2725d
[86.892271] Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 8b bb 0d 00 f7 d8 64 89 01 48
[86.892276] RSP: 002b:00007ffddd1fdb38 EFLAGS: 00000246 ORIG_RAX: 0000000000000139
[86.892281] RAX: ffffffffffffffda RBX: 00005d771d88fd90 RCX: 00007303e1b2725d
[86.892285] RDX: 0000000000000000 RSI: 00005d771d893aa0 RDI: 000000000000000c
[86.892287] RBP: 00007ffddd1fdbf0 R08: 0000000000000040 R09: 00007ffddd1fdb80
[86.892289] R10: 00007303e1c03b20 R11: 0000000000000246 R12: 00005d771d893aa0
[86.892292] R13: 0000000000000000 R14: 00005d771d88f0d0 R15: 00005d771d895710
[86.892304]  </TASK>

Call asynchronous variant of dma_fence_work_commit() in that case.

v3: Provide more verbose in-line comment (Andi),
  - mention target environments in commit message.

Fixes: 7d1c261 ("drm/i915: Take reservation lock around i915_vma_pin.")
Closes: https://gitlab.freedesktop.org/drm/i915/kernel/-/issues/14985
Cc: Andi Shyti <andi.shyti@kernel.org>
Signed-off-by: Janusz Krzysztofik <janusz.krzysztofik@linux.intel.com>
Reviewed-by: Sebastian Brzezinka <sebastian.brzezinka@intel.com>
Reviewed-by: Krzysztof Karas <krzysztof.karas@intel.com>
Acked-by: Andi Shyti <andi.shyti@linux.intel.com>
Signed-off-by: Andi Shyti <andi.shyti@linux.intel.com>
Link: https://lore.kernel.org/r/20251023082925.351307-6-janusz.krzysztofik@linux.intel.com
(cherry picked from commit 648ef13)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
mdroth pushed a commit that referenced this pull request Dec 15, 2025
When a connector is connected but inactive (e.g., disabled by desktop
environments), pipe_ctx->stream_res.tg will be destroyed. Then, reading
odm_combine_segments causes kernel NULL pointer dereference.

 BUG: kernel NULL pointer dereference, address: 0000000000000000
 #PF: supervisor read access in kernel mode
 #PF: error_code(0x0000) - not-present page
 PGD 0 P4D 0
 Oops: Oops: 0000 [#1] SMP NOPTI
 CPU: 16 UID: 0 PID: 26474 Comm: cat Not tainted 6.17.0+ #2 PREEMPT(lazy)  e6a17af9ee6db7c63e9d90dbe5b28ccab67520c6
 Hardware name: LENOVO 21Q4/LNVNB161216, BIOS PXCN25WW 03/27/2025
 RIP: 0010:odm_combine_segments_show+0x93/0xf0 [amdgpu]
 Code: 41 83 b8 b0 00 00 00 01 75 6e 48 98 ba a1 ff ff ff 48 c1 e0 0c 48 8d 8c 07 d8 02 00 00 48 85 c9 74 2d 48 8b bc 07 f0 08 00 00 <48> 8b 07 48 8b 80 08 02 00>
 RSP: 0018:ffffd1bf4b953c58 EFLAGS: 00010286
 RAX: 0000000000005000 RBX: ffff8e35976b02d0 RCX: ffff8e3aeed052d8
 RDX: 00000000ffffffa1 RSI: ffff8e35a3120800 RDI: 0000000000000000
 RBP: 0000000000000000 R08: ffff8e3580eb0000 R09: ffff8e35976b02d0
 R10: ffffd1bf4b953c78 R11: 0000000000000000 R12: ffffd1bf4b953d08
 R13: 0000000000040000 R14: 0000000000000001 R15: 0000000000000001
 FS:  00007f44d3f9f740(0000) GS:ffff8e3caa47f000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 0000000000000000 CR3: 00000006485c2000 CR4: 0000000000f50ef0
 PKRU: 55555554
 Call Trace:
  <TASK>
  seq_read_iter+0x125/0x490
  ? __alloc_frozen_pages_noprof+0x18f/0x350
  seq_read+0x12c/0x170
  full_proxy_read+0x51/0x80
  vfs_read+0xbc/0x390
  ? __handle_mm_fault+0xa46/0xef0
  ? do_syscall_64+0x71/0x900
  ksys_read+0x73/0xf0
  do_syscall_64+0x71/0x900
  ? count_memcg_events+0xc2/0x190
  ? handle_mm_fault+0x1d7/0x2d0
  ? do_user_addr_fault+0x21a/0x690
  ? exc_page_fault+0x7e/0x1a0
  entry_SYSCALL_64_after_hwframe+0x6c/0x74
 RIP: 0033:0x7f44d4031687
 Code: 48 89 fa 4c 89 df e8 58 b3 00 00 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 1a 5b c3 0f 1f 84 00 00 00 00 00 48 8b 44 24 10 0f 05 <5b> c3 0f 1f 80 00 00 00 00>
 RSP: 002b:00007ffdb4b5f0b0 EFLAGS: 00000202 ORIG_RAX: 0000000000000000
 RAX: ffffffffffffffda RBX: 00007f44d3f9f740 RCX: 00007f44d4031687
 RDX: 0000000000040000 RSI: 00007f44d3f5e000 RDI: 0000000000000003
 RBP: 0000000000040000 R08: 0000000000000000 R09: 0000000000000000
 R10: 0000000000000000 R11: 0000000000000202 R12: 00007f44d3f5e000
 R13: 0000000000000003 R14: 0000000000000000 R15: 0000000000040000
  </TASK>
 Modules linked in: tls tcp_diag inet_diag xt_mark ccm snd_hrtimer snd_seq_dummy snd_seq_midi snd_seq_oss snd_seq_midi_event snd_rawmidi snd_seq snd_seq_device x>
  snd_hda_codec_atihdmi snd_hda_codec_realtek_lib lenovo_wmi_helpers think_lmi snd_hda_codec_generic snd_hda_codec_hdmi snd_soc_core kvm snd_compress uvcvideo sn>
  platform_profile joydev amd_pmc mousedev mac_hid sch_fq_codel uinput i2c_dev parport_pc ppdev lp parport nvme_fabrics loop nfnetlink ip_tables x_tables dm_cryp>
 CR2: 0000000000000000
 ---[ end trace 0000000000000000 ]---
 RIP: 0010:odm_combine_segments_show+0x93/0xf0 [amdgpu]
 Code: 41 83 b8 b0 00 00 00 01 75 6e 48 98 ba a1 ff ff ff 48 c1 e0 0c 48 8d 8c 07 d8 02 00 00 48 85 c9 74 2d 48 8b bc 07 f0 08 00 00 <48> 8b 07 48 8b 80 08 02 00>
 RSP: 0018:ffffd1bf4b953c58 EFLAGS: 00010286
 RAX: 0000000000005000 RBX: ffff8e35976b02d0 RCX: ffff8e3aeed052d8
 RDX: 00000000ffffffa1 RSI: ffff8e35a3120800 RDI: 0000000000000000
 RBP: 0000000000000000 R08: ffff8e3580eb0000 R09: ffff8e35976b02d0
 R10: ffffd1bf4b953c78 R11: 0000000000000000 R12: ffffd1bf4b953d08
 R13: 0000000000040000 R14: 0000000000000001 R15: 0000000000000001
 FS:  00007f44d3f9f740(0000) GS:ffff8e3caa47f000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 0000000000000000 CR3: 00000006485c2000 CR4: 0000000000f50ef0
 PKRU: 55555554

Fix this by checking pipe_ctx->stream_res.tg before dereferencing.

Fixes: 07926ba ("drm/amd/display: Add debugfs interface for ODM combine info")
Signed-off-by: Rong Zhang <i@rong.moe>
Reviewed-by: Mario Limoncello <mario.limonciello@amd.com>
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
(cherry picked from commit f19bbec)
Cc: stable@vger.kernel.org
mdroth pushed a commit that referenced this pull request Dec 15, 2025
…or slabobj_ext

When alloc_slab_obj_exts() fails and then later succeeds in allocating a
slab extension vector, it calls handle_failed_objexts_alloc() to mark all
objects in the vector as empty.  As a result all objects in this slab
(slabA) will have their extensions set to CODETAG_EMPTY.

Later on if this slabA is used to allocate a slabobj_ext vector for
another slab (slabB), we end up with the slabB->obj_exts pointing to a
slabobj_ext vector that itself has a non-NULL slabobj_ext equal to
CODETAG_EMPTY.  When slabB gets freed, free_slab_obj_exts() is called to
free slabB->obj_exts vector.  

free_slab_obj_exts() calls mark_objexts_empty(slabB->obj_exts) which will
generate a warning because it expects slabobj_ext vectors to have a NULL
obj_ext, not CODETAG_EMPTY.

Modify mark_objexts_empty() to skip the warning and setting the obj_ext
value if it's already set to CODETAG_EMPTY.


To quickly detect this WARN, I modified the code from
WARN_ON(slab_exts[offs].ref.ct) to BUG_ON(slab_exts[offs].ref.ct == 1);

We then obtained this message:

[21630.898561] ------------[ cut here ]------------
[21630.898596] kernel BUG at mm/slub.c:2050!
[21630.898611] Internal error: Oops - BUG: 00000000f2000800 [#1] SMP
[21630.900372] Modules linked in: squashfs isofs vfio_iommu_type1 
vhost_vsock vfio vhost_net vmw_vsock_virtio_transport_common vhost tap 
vhost_iotlb iommufd vsock binfmt_misc nfsv3 nfs_acl nfs lockd grace 
netfs tls rds dns_resolver tun brd overlay ntfs3 exfat btrfs 
blake2b_generic xor xor_neon raid6_pq loop sctp ip6_udp_tunnel 
udp_tunnel nft_fib_inet nft_fib_ipv4 nft_fib_ipv6 nft_fib 
nft_reject_inet nf_reject_ipv4 nf_reject_ipv6 nft_reject nft_ct 
nft_chain_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 
nf_tables rfkill ip_set sunrpc vfat fat joydev sg sch_fq_codel nfnetlink 
virtio_gpu sr_mod cdrom drm_client_lib virtio_dma_buf drm_shmem_helper 
drm_kms_helper drm ghash_ce backlight virtio_net virtio_blk virtio_scsi 
net_failover virtio_console failover virtio_mmio dm_mirror 
dm_region_hash dm_log dm_multipath dm_mod fuse i2c_dev virtio_pci 
virtio_pci_legacy_dev virtio_pci_modern_dev virtio virtio_ring autofs4 
aes_neon_bs aes_ce_blk [last unloaded: hwpoison_inject]
[21630.909177] CPU: 3 UID: 0 PID: 3787 Comm: kylin-process-m Kdump: 
loaded Tainted: G        W           6.18.0-rc1+ torvalds#74 PREEMPT(voluntary)
[21630.910495] Tainted: [W]=WARN
[21630.910867] Hardware name: QEMU KVM Virtual Machine, BIOS unknown 
2/2/2022
[21630.911625] pstate: 80400005 (Nzcv daif +PAN -UAO -TCO -DIT -SSBS 
BTYPE=--)
[21630.912392] pc : __free_slab+0x228/0x250
[21630.912868] lr : __free_slab+0x18c/0x250[21630.913334] sp : 
ffff8000a02f73e0
[21630.913830] x29: ffff8000a02f73e0 x28: fffffdffc43fc800 x27: 
ffff0000c0011c40
[21630.914677] x26: ffff0000c000cac0 x25: ffff00010fe5e5f0 x24: 
ffff000102199b40
[21630.915469] x23: 0000000000000003 x22: 0000000000000003 x21: 
ffff0000c0011c40
[21630.916259] x20: fffffdffc4086600 x19: fffffdffc43fc800 x18: 
0000000000000000
[21630.917048] x17: 0000000000000000 x16: 0000000000000000 x15: 
0000000000000000
[21630.917837] x14: 0000000000000000 x13: 0000000000000000 x12: 
ffff70001405ee66
[21630.918640] x11: 1ffff0001405ee65 x10: ffff70001405ee65 x9 : 
ffff800080a295dc
[21630.919442] x8 : ffff8000a02f7330 x7 : 0000000000000000 x6 : 
0000000000003000
[21630.920232] x5 : 0000000024924925 x4 : 0000000000000001 x3 : 
0000000000000007
[21630.921021] x2 : 0000000000001b40 x1 : 000000000000001f x0 : 
0000000000000001
[21630.921810] Call trace:
[21630.922130]  __free_slab+0x228/0x250 (P)
[21630.922669]  free_slab+0x38/0x118
[21630.923079]  free_to_partial_list+0x1d4/0x340
[21630.923591]  __slab_free+0x24c/0x348
[21630.924024]  ___cache_free+0xf0/0x110
[21630.924468]  qlist_free_all+0x78/0x130
[21630.924922]  kasan_quarantine_reduce+0x114/0x148
[21630.925525]  __kasan_slab_alloc+0x7c/0xb0
[21630.926006]  kmem_cache_alloc_noprof+0x164/0x5c8
[21630.926699]  __alloc_object+0x44/0x1f8
[21630.927153]  __create_object+0x34/0xc8
[21630.927604]  kmemleak_alloc+0xb8/0xd8
[21630.928052]  kmem_cache_alloc_noprof+0x368/0x5c8
[21630.928606]  getname_flags.part.0+0xa4/0x610
[21630.929112]  getname_flags+0x80/0xd8
[21630.929557]  vfs_fstatat+0xc8/0xe0
[21630.929975]  __do_sys_newfstatat+0xa0/0x100
[21630.930469]  __arm64_sys_newfstatat+0x90/0xd8
[21630.931046]  invoke_syscall+0xd4/0x258
[21630.931685]  el0_svc_common.constprop.0+0xb4/0x240
[21630.932467]  do_el0_svc+0x48/0x68
[21630.932972]  el0_svc+0x40/0xe0
[21630.933472]  el0t_64_sync_handler+0xa0/0xe8
[21630.934151]  el0t_64_sync+0x1ac/0x1b0
[21630.934923] Code: aa1803e0 97ffef2b a9446bf9 17ffff9c (d4210000)
[21630.936461] SMP: stopping secondary CPUs
[21630.939550] Starting crashdump kernel...
[21630.940108] Bye!

Link: https://lkml.kernel.org/r/20251029014317.1533488-1-hao.ge@linux.dev
Fixes: 09c4656 ("codetag: debug: introduce OBJEXTS_ALLOC_FAIL to mark failed slab_ext allocations")
Signed-off-by: Hao Ge <gehao@kylinos.cn>
Reviewed-by: Suren Baghdasaryan <surenb@google.com>
Cc: Christoph Lameter (Ampere) <cl@gentwo.org>
Cc: David Rientjes <rientjes@google.com>
Cc: gehao <gehao@kylinos.cn>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
mdroth pushed a commit that referenced this pull request Dec 15, 2025
Typically copynotify stateid is freed either when parent's stateid
is being close/freed or in nfsd4_laundromat if the stateid hasn't
been used in a lease period.

However, in case when the server got an OPEN (which created
a parent stateid), followed by a COPY_NOTIFY using that stateid,
followed by a client reboot. New client instance while doing
CREATE_SESSION would force expire previous state of this client.
It leads to the open state being freed thru release_openowner->
nfs4_free_ol_stateid() and it finds that it still has copynotify
stateid associated with it. We currently print a warning and is
triggerred

WARNING: CPU: 1 PID: 8858 at fs/nfsd/nfs4state.c:1550 nfs4_free_ol_stateid+0xb0/0x100 [nfsd]

This patch, instead, frees the associated copynotify stateid here.

If the parent stateid is freed (without freeing the copynotify
stateids associated with it), it leads to the list corruption
when laundromat ends up freeing the copynotify state later.

[ 1626.839430] Internal error: Oops - BUG: 00000000f2000800 [#1]  SMP
[ 1626.842828] Modules linked in: nfnetlink_queue nfnetlink_log bluetooth cfg80211 rpcrdma rdma_cm iw_cm ib_cm ib_core nfsd nfs_acl lockd grace nfs_localio ext4 crc16 mbcache jbd2 overlay uinput snd_seq_dummy snd_hrtimer qrtr rfkill vfat fat uvcvideo snd_hda_codec_generic videobuf2_vmalloc videobuf2_memops snd_hda_intel uvc snd_intel_dspcfg videobuf2_v4l2 videobuf2_common snd_hda_codec snd_hda_core videodev snd_hwdep snd_seq mc snd_seq_device snd_pcm snd_timer snd soundcore sg loop auth_rpcgss vsock_loopback vmw_vsock_virtio_transport_common vmw_vsock_vmci_transport vmw_vmci vsock xfs 8021q garp stp llc mrp nvme ghash_ce e1000e nvme_core sr_mod nvme_keyring nvme_auth cdrom vmwgfx drm_ttm_helper ttm sunrpc dm_mirror dm_region_hash dm_log iscsi_tcp libiscsi_tcp libiscsi scsi_transport_iscsi fuse dm_multipath dm_mod nfnetlink
[ 1626.855594] CPU: 2 UID: 0 PID: 199 Comm: kworker/u24:33 Kdump: loaded Tainted: G    B   W           6.17.0-rc7+ torvalds#22 PREEMPT(voluntary)
[ 1626.857075] Tainted: [B]=BAD_PAGE, [W]=WARN
[ 1626.857573] Hardware name: VMware, Inc. VMware20,1/VBSA, BIOS VMW201.00V.24006586.BA64.2406042154 06/04/2024
[ 1626.858724] Workqueue: nfsd4 laundromat_main [nfsd]
[ 1626.859304] pstate: 6140000 (nZCv daif +PAN -UAO -TCO +DIT -SSBS BTYPE=--)
[ 1626.860010] pc : __list_del_entry_valid_or_report+0x148/0x200
[ 1626.860601] lr : __list_del_entry_valid_or_report+0x148/0x200
[ 1626.861182] sp : ffff8000881d7a40
[ 1626.861521] x29: ffff8000881d7a40 x28: 0000000000000018 x27: ffff0000c2a98200
[ 1626.862260] x26: 0000000000000600 x25: 0000000000000000 x24: ffff8000881d7b20
[ 1626.862986] x23: ffff0000c2a981e8 x22: 1fffe00012410e7d x21: ffff0000920873e8
[ 1626.863701] x20: ffff0000920873e8 x19: ffff000086f22998 x18: 0000000000000000
[ 1626.864421] x17: 20747562202c3839 x16: 3932326636383030 x15: 3030666666662065
[ 1626.865092] x14: 6220646c756f6873 x13: 0000000000000001 x12: ffff60004fd9e4a3
[ 1626.865713] x11: 1fffe0004fd9e4a2 x10: ffff60004fd9e4a2 x9 : dfff800000000000
[ 1626.866320] x8 : 00009fffb0261b5e x7 : ffff00027ecf2513 x6 : 0000000000000001
[ 1626.866938] x5 : ffff00027ecf2510 x4 : ffff60004fd9e4a3 x3 : 0000000000000000
[ 1626.867553] x2 : 0000000000000000 x1 : ffff000096069640 x0 : 000000000000006d
[ 1626.868167] Call trace:
[ 1626.868382]  __list_del_entry_valid_or_report+0x148/0x200 (P)
[ 1626.868876]  _free_cpntf_state_locked+0xd0/0x268 [nfsd]
[ 1626.869368]  nfs4_laundromat+0x6f8/0x1058 [nfsd]
[ 1626.869813]  laundromat_main+0x24/0x60 [nfsd]
[ 1626.870231]  process_one_work+0x584/0x1050
[ 1626.870595]  worker_thread+0x4c4/0xc60
[ 1626.870893]  kthread+0x2f8/0x398
[ 1626.871146]  ret_from_fork+0x10/0x20
[ 1626.871422] Code: aa1303e1 aa1403e3 910e8000 97bc55d7 (d4210000)
[ 1626.871892] SMP: stopping secondary CPUs

Reported-by: rtm@csail.mit.edu
Closes: https://lore.kernel.org/linux-nfs/d8f064c1-a26f-4eed-b4f0-1f7f608f415f@oracle.com/T/#t
Fixes: 624322f ("NFSD add COPY_NOTIFY operation")
Cc: stable@vger.kernel.org
Signed-off-by: Olga Kornievskaia <okorniev@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
mdroth pushed a commit that referenced this pull request Dec 15, 2025
When freeing indexed arrays, the corresponding free function should
be called for each entry of the indexed array. For example, for
for 'struct tc_act_attrs' 'tc_act_attrs_free(...)' needs to be called
for each entry.

Previously, memory leaks were reported when enabling the ASAN
analyzer.

=================================================================
==874==ERROR: LeakSanitizer: detected memory leaks

Direct leak of 24 byte(s) in 1 object(s) allocated from:
    #0 0x7f221fd20cb5 in malloc ./debug/gcc/gcc/libsanitizer/asan/asan_malloc_linux.cpp:67
    #1 0x55c98db048af in tc_act_attrs_set_options_vlan_parms ../generated/tc-user.h:2813
    #2 0x55c98db048af in main  ./linux/tools/net/ynl/samples/tc-filter-add.c:71

Direct leak of 24 byte(s) in 1 object(s) allocated from:
    #0 0x7f221fd20cb5 in malloc ./debug/gcc/gcc/libsanitizer/asan/asan_malloc_linux.cpp:67
    #1 0x55c98db04a93 in tc_act_attrs_set_options_vlan_parms ../generated/tc-user.h:2813
    #2 0x55c98db04a93 in main ./linux/tools/net/ynl/samples/tc-filter-add.c:74

Direct leak of 10 byte(s) in 2 object(s) allocated from:
    #0 0x7f221fd20cb5 in malloc ./debug/gcc/gcc/libsanitizer/asan/asan_malloc_linux.cpp:67
    #1 0x55c98db0527d in tc_act_attrs_set_kind ../generated/tc-user.h:1622

SUMMARY: AddressSanitizer: 58 byte(s) leaked in 4 allocation(s).

The following diff illustrates the changes introduced compared to the
previous version of the code.

 void tc_flower_attrs_free(struct tc_flower_attrs *obj)
 {
+	unsigned int i;
+
 	free(obj->indev);
+	for (i = 0; i < obj->_count.act; i++)
+		tc_act_attrs_free(&obj->act[i]);
 	free(obj->act);
 	free(obj->key_eth_dst);
 	free(obj->key_eth_dst_mask);

Signed-off-by: Zahari Doychev <zahari.doychev@linux.com>
Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Link: https://patch.msgid.link/20251106151529.453026-3-zahari.doychev@linux.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
mdroth pushed a commit that referenced this pull request Dec 15, 2025
When crashkernel is configured with a high reservation, shrinking its
value below the low crashkernel reservation causes two issues:

1. Invalid crashkernel resource objects
2. Kernel crash if crashkernel shrinking is done twice

For example, with crashkernel=200M,high, the kernel reserves 200MB of high
memory and some default low memory (say 256MB).  The reservation appears
as:

cat /proc/iomem | grep -i crash
af000000-beffffff : Crash kernel
433000000-43f7fffff : Crash kernel

If crashkernel is then shrunk to 50MB (echo 52428800 >
/sys/kernel/kexec_crash_size), /proc/iomem still shows 256MB reserved:
af000000-beffffff : Crash kernel

Instead, it should show 50MB:
af000000-b21fffff : Crash kernel

Further shrinking crashkernel to 40MB causes a kernel crash with the
following trace (x86):

BUG: kernel NULL pointer dereference, address: 0000000000000038
PGD 0 P4D 0
Oops: 0000 [#1] PREEMPT SMP NOPTI
<snip...>
Call Trace: <TASK>
? __die_body.cold+0x19/0x27
? page_fault_oops+0x15a/0x2f0
? search_module_extables+0x19/0x60
? search_bpf_extables+0x5f/0x80
? exc_page_fault+0x7e/0x180
? asm_exc_page_fault+0x26/0x30
? __release_resource+0xd/0xb0
release_resource+0x26/0x40
__crash_shrink_memory+0xe5/0x110
crash_shrink_memory+0x12a/0x190
kexec_crash_size_store+0x41/0x80
kernfs_fop_write_iter+0x141/0x1f0
vfs_write+0x294/0x460
ksys_write+0x6d/0xf0
<snip...>

This happens because __crash_shrink_memory()/kernel/crash_core.c
incorrectly updates the crashk_res resource object even when
crashk_low_res should be updated.

Fix this by ensuring the correct crashkernel resource object is updated
when shrinking crashkernel memory.

Link: https://lkml.kernel.org/r/20251101193741.289252-1-sourabhjain@linux.ibm.com
Fixes: 16c6006 ("kexec: enable kexec_crash_size to support two crash kernel regions")
Signed-off-by: Sourabh Jain <sourabhjain@linux.ibm.com>
Acked-by: Baoquan He <bhe@redhat.com>
Cc: Zhen Lei <thunder.leizhen@huawei.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
mdroth pushed a commit that referenced this pull request Dec 15, 2025
When emulating an nvme device on qemu with both logical_block_size and
physical_block_size set to 8 KiB, but without format, a kernel panic
was triggered during the early boot stage while attempting to mount a
vfat filesystem.

[95553.682035] EXT4-fs (nvme0n1): unable to set blocksize
[95553.684326] EXT4-fs (nvme0n1): unable to set blocksize
[95553.686501] EXT4-fs (nvme0n1): unable to set blocksize
[95553.696448] ISOFS: unsupported/invalid hardware sector size 8192
[95553.697117] ------------[ cut here ]------------
[95553.697567] kernel BUG at fs/buffer.c:1582!
[95553.697984] Oops: invalid opcode: 0000 [#1] SMP NOPTI
[95553.698602] CPU: 0 UID: 0 PID: 7212 Comm: mount Kdump: loaded Not tainted 6.18.0-rc2+ torvalds#38 PREEMPT(voluntary)
[95553.699511] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
[95553.700534] RIP: 0010:folio_alloc_buffers+0x1bb/0x1c0
[95553.701018] Code: 48 8b 15 e8 93 18 02 65 48 89 35 e0 93 18 02 48 83 c4 10 5b 41 5c 41 5d 41 5e 41 5f 5d 31 d2 31 c9 31 f6 31 ff c3 cc cc cc cc <0f> 0b 90 66 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f
[95553.702648] RSP: 0018:ffffd1b0c676f990 EFLAGS: 00010246
[95553.703132] RAX: ffff8cfc4176d820 RBX: 0000000000508c48 RCX: 0000000000000001
[95553.703805] RDX: 0000000000002000 RSI: 0000000000000000 RDI: 0000000000000000
[95553.704481] RBP: ffffd1b0c676f9c8 R08: 0000000000000000 R09: 0000000000000000
[95553.705148] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000001
[95553.705816] R13: 0000000000002000 R14: fffff8bc8257e800 R15: 0000000000000000
[95553.706483] FS:  000072ee77315840(0000) GS:ffff8cfdd2c8d000(0000) knlGS:0000000000000000
[95553.707248] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[95553.707782] CR2: 00007d8f2a9e5a20 CR3: 0000000039d0c006 CR4: 0000000000772ef0
[95553.708439] PKRU: 55555554
[95553.708734] Call Trace:
[95553.709015]  <TASK>
[95553.709266]  __getblk_slow+0xd2/0x230
[95553.709641]  ? find_get_block_common+0x8b/0x530
[95553.710084]  bdev_getblk+0x77/0xa0
[95553.710449]  __bread_gfp+0x22/0x140
[95553.710810]  fat_fill_super+0x23a/0xfc0
[95553.711216]  ? __pfx_setup+0x10/0x10
[95553.711580]  ? __pfx_vfat_fill_super+0x10/0x10
[95553.712014]  vfat_fill_super+0x15/0x30
[95553.712401]  get_tree_bdev_flags+0x141/0x1e0
[95553.712817]  get_tree_bdev+0x10/0x20
[95553.713177]  vfat_get_tree+0x15/0x20
[95553.713550]  vfs_get_tree+0x2a/0x100
[95553.713910]  vfs_cmd_create+0x62/0xf0
[95553.714273]  __do_sys_fsconfig+0x4e7/0x660
[95553.714669]  __x64_sys_fsconfig+0x20/0x40
[95553.715062]  x64_sys_call+0x21ee/0x26a0
[95553.715453]  do_syscall_64+0x80/0x670
[95553.715816]  ? __fs_parse+0x65/0x1e0
[95553.716172]  ? fat_parse_param+0x103/0x4b0
[95553.716587]  ? vfs_parse_fs_param_source+0x21/0xa0
[95553.717034]  ? __do_sys_fsconfig+0x3d9/0x660
[95553.717548]  ? __x64_sys_fsconfig+0x20/0x40
[95553.717957]  ? x64_sys_call+0x21ee/0x26a0
[95553.718360]  ? do_syscall_64+0xb8/0x670
[95553.718734]  ? __x64_sys_fsconfig+0x20/0x40
[95553.719141]  ? x64_sys_call+0x21ee/0x26a0
[95553.719545]  ? do_syscall_64+0xb8/0x670
[95553.719922]  ? x64_sys_call+0x1405/0x26a0
[95553.720317]  ? do_syscall_64+0xb8/0x670
[95553.720702]  ? __x64_sys_close+0x3e/0x90
[95553.721080]  ? x64_sys_call+0x1b5e/0x26a0
[95553.721478]  ? do_syscall_64+0xb8/0x670
[95553.721841]  ? irqentry_exit+0x43/0x50
[95553.722211]  ? exc_page_fault+0x90/0x1b0
[95553.722681]  entry_SYSCALL_64_after_hwframe+0x76/0x7e
[95553.723166] RIP: 0033:0x72ee774f3afe
[95553.723562] Code: 73 01 c3 48 8b 0d 0a 33 0f 00 f7 d8 64 89 01 48 83 c8 ff c3 0f 1f 84 00 00 00 00 00 f3 0f 1e fa 49 89 ca b8 af 01 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d da 32 0f 00 f7 d8 64 89 01 48
[95553.725188] RSP: 002b:00007ffe97148978 EFLAGS: 00000246 ORIG_RAX: 00000000000001af
[95553.725892] RAX: ffffffffffffffda RBX: 00005dcfe53d0080 RCX: 000072ee774f3afe
[95553.726526] RDX: 0000000000000000 RSI: 0000000000000006 RDI: 0000000000000003
[95553.727176] RBP: 00007ffe97148ac0 R08: 0000000000000000 R09: 000072ee775e7ac0
[95553.727818] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
[95553.728459] R13: 00005dcfe53d04b0 R14: 000072ee77670b00 R15: 00005dcfe53d1a28
[95553.729086]  </TASK>

The panic occurs as follows:
1. logical_block_size is 8KiB, causing {struct super_block *sb}->s_blocksize
is initialized to 0.
vfat_fill_super
 - fat_fill_super
  - sb_min_blocksize
   - sb_set_blocksize //return 0 when size is 8KiB.
2. __bread_gfp is called with size == 0, causing folio_alloc_buffers() to
compute an offset equal to folio_size(folio), which triggers a BUG_ON.
fat_fill_super
 - sb_bread
  - __bread_gfp  // size == {struct super_block *sb}->s_blocksize == 0
   - bdev_getblk
    - __getblk_slow
     - grow_buffers
      - grow_dev_folio
       - folio_alloc_buffers  // size == 0
        - folio_set_bh //offset == folio_size(folio) and panic

To fix this issue, add proper return value checks for
sb_min_blocksize().

Cc: stable@vger.kernel.org # v6.15
Fixes: a64e5a5 ("bdev: add back PAGE_SIZE block size validation for sb_set_blocksize()")
Reviewed-by: Matthew Wilcox <willy@infradead.org>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Yongpeng Yang <yangyongpeng@xiaomi.com>
Link: https://patch.msgid.link/20251104125009.2111925-2-yangyongpeng.storage@gmail.com
Acked-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Christian Brauner <brauner@kernel.org>
mdroth pushed a commit that referenced this pull request Dec 15, 2025
The validation of the set(nsh(...)) action is completely wrong.
It runs through the nsh_key_put_from_nlattr() function that is the
same function that validates NSH keys for the flow match and the
push_nsh() action.  However, the set(nsh(...)) has a very different
memory layout.  Nested attributes in there are doubled in size in
case of the masked set().  That makes proper validation impossible.

There is also confusion in the code between the 'masked' flag, that
says that the nested attributes are doubled in size containing both
the value and the mask, and the 'is_mask' that says that the value
we're parsing is the mask.  This is causing kernel crash on trying to
write into mask part of the match with SW_FLOW_KEY_PUT() during
validation, while validate_nsh() doesn't allocate any memory for it:

  BUG: kernel NULL pointer dereference, address: 0000000000000018
  #PF: supervisor read access in kernel mode
  #PF: error_code(0x0000) - not-present page
  PGD 1c2383067 P4D 1c2383067 PUD 20b703067 PMD 0
  Oops: Oops: 0000 [#1] SMP NOPTI
  CPU: 8 UID: 0 Kdump: loaded Not tainted 6.17.0-rc4+ torvalds#107 PREEMPT(voluntary)
  RIP: 0010:nsh_key_put_from_nlattr+0x19d/0x610 [openvswitch]
  Call Trace:
   <TASK>
   validate_nsh+0x60/0x90 [openvswitch]
   validate_set.constprop.0+0x270/0x3c0 [openvswitch]
   __ovs_nla_copy_actions+0x477/0x860 [openvswitch]
   ovs_nla_copy_actions+0x8d/0x100 [openvswitch]
   ovs_packet_cmd_execute+0x1cc/0x310 [openvswitch]
   genl_family_rcv_msg_doit+0xdb/0x130
   genl_family_rcv_msg+0x14b/0x220
   genl_rcv_msg+0x47/0xa0
   netlink_rcv_skb+0x53/0x100
   genl_rcv+0x24/0x40
   netlink_unicast+0x280/0x3b0
   netlink_sendmsg+0x1f7/0x430
   ____sys_sendmsg+0x36b/0x3a0
   ___sys_sendmsg+0x87/0xd0
   __sys_sendmsg+0x6d/0xd0
   do_syscall_64+0x7b/0x2c0
   entry_SYSCALL_64_after_hwframe+0x76/0x7e

The third issue with this process is that while trying to convert
the non-masked set into masked one, validate_set() copies and doubles
the size of the OVS_KEY_ATTR_NSH as if it didn't have any nested
attributes.  It should be copying each nested attribute and doubling
them in size independently.  And the process must be properly reversed
during the conversion back from masked to a non-masked variant during
the flow dump.

In the end, the only two outcomes of trying to use this action are
either validation failure or a kernel crash.  And if somehow someone
manages to install a flow with such an action, it will most definitely
not do what it is supposed to, since all the keys and the masks are
mixed up.

Fixing all the issues is a complex task as it requires re-writing
most of the validation code.

Given that and the fact that this functionality never worked since
introduction, let's just remove it altogether.  It's better to
re-introduce it later with a proper implementation instead of trying
to fix it in stable releases.

Fixes: b2d0f5d ("openvswitch: enable NSH support")
Reported-by: Junvy Yang <zhuque@tencent.com>
Signed-off-by: Ilya Maximets <i.maximets@ovn.org>
Acked-by: Eelco Chaudron <echaudro@redhat.com>
Reviewed-by: Aaron Conole <aconole@redhat.com>
Link: https://patch.msgid.link/20251112112246.95064-1-i.maximets@ovn.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
mdroth pushed a commit that referenced this pull request Dec 15, 2025
The function devl_rate_nodes_destroy is documented to "Unset parent for
all rate objects". However, it was only calling the driver-specific
`rate_leaf_parent_set` or `rate_node_parent_set` ops and decrementing
the parent's refcount, without actually setting the
`devlink_rate->parent` pointer to NULL.

This leaves a dangling pointer in the `devlink_rate` struct, which cause
refcount error in netdevsim[1] and mlx5[2]. In addition, this is
inconsistent with the behavior of `devlink_nl_rate_parent_node_set`,
where the parent pointer is correctly cleared.

This patch fixes the issue by explicitly setting `devlink_rate->parent`
to NULL after notifying the driver, thus fulfilling the function's
documented behavior for all rate objects.

[1]
repro steps:
echo 1 > /sys/bus/netdevsim/new_device
devlink dev eswitch set netdevsim/netdevsim1 mode switchdev
echo 1 > /sys/bus/netdevsim/devices/netdevsim1/sriov_numvfs
devlink port function rate add netdevsim/netdevsim1/test_node
devlink port function rate set netdevsim/netdevsim1/128 parent test_node
echo 1 > /sys/bus/netdevsim/del_device

dmesg:
refcount_t: decrement hit 0; leaking memory.
WARNING: CPU: 8 PID: 1530 at lib/refcount.c:31 refcount_warn_saturate+0x42/0xe0
CPU: 8 UID: 0 PID: 1530 Comm: bash Not tainted 6.18.0-rc4+ #1 NONE
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014
RIP: 0010:refcount_warn_saturate+0x42/0xe0
Call Trace:
 <TASK>
 devl_rate_leaf_destroy+0x8d/0x90
 __nsim_dev_port_del+0x6c/0x70 [netdevsim]
 nsim_dev_reload_destroy+0x11c/0x140 [netdevsim]
 nsim_drv_remove+0x2b/0xb0 [netdevsim]
 device_release_driver_internal+0x194/0x1f0
 bus_remove_device+0xc6/0x130
 device_del+0x159/0x3c0
 device_unregister+0x1a/0x60
 del_device_store+0x111/0x170 [netdevsim]
 kernfs_fop_write_iter+0x12e/0x1e0
 vfs_write+0x215/0x3d0
 ksys_write+0x5f/0xd0
 do_syscall_64+0x55/0x10f0
 entry_SYSCALL_64_after_hwframe+0x4b/0x53

[2]
devlink dev eswitch set pci/0000:08:00.0 mode switchdev
devlink port add pci/0000:08:00.0 flavour pcisf pfnum 0 sfnum 1000
devlink port function rate add pci/0000:08:00.0/group1
devlink port function rate set pci/0000:08:00.0/32768 parent group1
modprobe -r mlx5_ib mlx5_fwctl mlx5_core

dmesg:
refcount_t: decrement hit 0; leaking memory.
WARNING: CPU: 7 PID: 16151 at lib/refcount.c:31 refcount_warn_saturate+0x42/0xe0
CPU: 7 UID: 0 PID: 16151 Comm: bash Not tainted 6.17.0-rc7_for_upstream_min_debug_2025_10_02_12_44 #1 NONE
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
RIP: 0010:refcount_warn_saturate+0x42/0xe0
Call Trace:
 <TASK>
 devl_rate_leaf_destroy+0x8d/0x90
 mlx5_esw_offloads_devlink_port_unregister+0x33/0x60 [mlx5_core]
 mlx5_esw_offloads_unload_rep+0x3f/0x50 [mlx5_core]
 mlx5_eswitch_unload_sf_vport+0x40/0x90 [mlx5_core]
 mlx5_sf_esw_event+0xc4/0x120 [mlx5_core]
 notifier_call_chain+0x33/0xa0
 blocking_notifier_call_chain+0x3b/0x50
 mlx5_eswitch_disable_locked+0x50/0x110 [mlx5_core]
 mlx5_eswitch_disable+0x63/0x90 [mlx5_core]
 mlx5_unload+0x1d/0x170 [mlx5_core]
 mlx5_uninit_one+0xa2/0x130 [mlx5_core]
 remove_one+0x78/0xd0 [mlx5_core]
 pci_device_remove+0x39/0xa0
 device_release_driver_internal+0x194/0x1f0
 unbind_store+0x99/0xa0
 kernfs_fop_write_iter+0x12e/0x1e0
 vfs_write+0x215/0x3d0
 ksys_write+0x5f/0xd0
 do_syscall_64+0x53/0x1f0
 entry_SYSCALL_64_after_hwframe+0x4b/0x53

Fixes: d755598 ("devlink: Allow setting parent node of rate objects")
Signed-off-by: Shay Drory <shayd@nvidia.com>
Reviewed-by: Carolina Jubran <cjubran@nvidia.com>
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Link: https://patch.msgid.link/1763381149-1234377-1-git-send-email-tariqt@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
mdroth pushed a commit that referenced this pull request Dec 15, 2025
The mlx5_irq_alloc() function can inadvertently free the entire rmap
and end up in a crash[1] when the other threads tries to access this,
when request_irq() fails due to exhausted IRQ vectors. This commit
modifies the cleanup to remove only the specific IRQ mapping that was
just added.

This prevents removal of other valid mappings and ensures precise
cleanup of the failed IRQ allocation's associated glue object.

Note: This error is observed when both fwctl and rds configs are enabled.

[1]
mlx5_core 0000:05:00.0: Successfully registered panic handler for port 1
mlx5_core 0000:05:00.0: mlx5_irq_alloc:293:(pid 66740): Failed to
request irq. err = -28
infiniband mlx5_0: mlx5_ib_test_wc:290:(pid 66740): Error -28 while
trying to test write-combining support
mlx5_core 0000:05:00.0: Successfully unregistered panic handler for port 1
mlx5_core 0000:06:00.0: Successfully registered panic handler for port 1
mlx5_core 0000:06:00.0: mlx5_irq_alloc:293:(pid 66740): Failed to
request irq. err = -28
infiniband mlx5_0: mlx5_ib_test_wc:290:(pid 66740): Error -28 while
trying to test write-combining support
mlx5_core 0000:06:00.0: Successfully unregistered panic handler for port 1
mlx5_core 0000:03:00.0: mlx5_irq_alloc:293:(pid 28895): Failed to
request irq. err = -28
mlx5_core 0000:05:00.0: mlx5_irq_alloc:293:(pid 28895): Failed to
request irq. err = -28
general protection fault, probably for non-canonical address
0xe277a58fde16f291: 0000 [#1] SMP NOPTI

RIP: 0010:free_irq_cpu_rmap+0x23/0x7d
Call Trace:
   <TASK>
   ? show_trace_log_lvl+0x1d6/0x2f9
   ? show_trace_log_lvl+0x1d6/0x2f9
   ? mlx5_irq_alloc.cold+0x5d/0xf3 [mlx5_core]
   ? __die_body.cold+0x8/0xa
   ? die_addr+0x39/0x53
   ? exc_general_protection+0x1c4/0x3e9
   ? dev_vprintk_emit+0x5f/0x90
   ? asm_exc_general_protection+0x22/0x27
   ? free_irq_cpu_rmap+0x23/0x7d
   mlx5_irq_alloc.cold+0x5d/0xf3 [mlx5_core]
   irq_pool_request_vector+0x7d/0x90 [mlx5_core]
   mlx5_irq_request+0x2e/0xe0 [mlx5_core]
   mlx5_irq_request_vector+0xad/0xf7 [mlx5_core]
   comp_irq_request_pci+0x64/0xf0 [mlx5_core]
   create_comp_eq+0x71/0x385 [mlx5_core]
   ? mlx5e_open_xdpsq+0x11c/0x230 [mlx5_core]
   mlx5_comp_eqn_get+0x72/0x90 [mlx5_core]
   ? xas_load+0x8/0x91
   mlx5_comp_irqn_get+0x40/0x90 [mlx5_core]
   mlx5e_open_channel+0x7d/0x3c7 [mlx5_core]
   mlx5e_open_channels+0xad/0x250 [mlx5_core]
   mlx5e_open_locked+0x3e/0x110 [mlx5_core]
   mlx5e_open+0x23/0x70 [mlx5_core]
   __dev_open+0xf1/0x1a5
   __dev_change_flags+0x1e1/0x249
   dev_change_flags+0x21/0x5c
   do_setlink+0x28b/0xcc4
   ? __nla_parse+0x22/0x3d
   ? inet6_validate_link_af+0x6b/0x108
   ? cpumask_next+0x1f/0x35
   ? __snmp6_fill_stats64.constprop.0+0x66/0x107
   ? __nla_validate_parse+0x48/0x1e6
   __rtnl_newlink+0x5ff/0xa57
   ? kmem_cache_alloc_trace+0x164/0x2ce
   rtnl_newlink+0x44/0x6e
   rtnetlink_rcv_msg+0x2bb/0x362
   ? __netlink_sendskb+0x4c/0x6c
   ? netlink_unicast+0x28f/0x2ce
   ? rtnl_calcit.isra.0+0x150/0x146
   netlink_rcv_skb+0x5f/0x112
   netlink_unicast+0x213/0x2ce
   netlink_sendmsg+0x24f/0x4d9
   __sock_sendmsg+0x65/0x6a
   ____sys_sendmsg+0x28f/0x2c9
   ? import_iovec+0x17/0x2b
   ___sys_sendmsg+0x97/0xe0
   __sys_sendmsg+0x81/0xd8
   do_syscall_64+0x35/0x87
   entry_SYSCALL_64_after_hwframe+0x6e/0x0
RIP: 0033:0x7fc328603727
Code: c3 66 90 41 54 41 89 d4 55 48 89 f5 53 89 fb 48 83 ec 10 e8 0b ed
ff ff 44 89 e2 48 89 ee 89 df 41 89 c0 b8 2e 00 00 00 0f 05 <48> 3d 00
f0 ff ff 77 35 44 89 c7 48 89 44 24 08 e8 44 ed ff ff 48
RSP: 002b:00007ffe8eb3f1a0 EFLAGS: 00000293 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 000000000000000d RCX: 00007fc328603727
RDX: 0000000000000000 RSI: 00007ffe8eb3f1f0 RDI: 000000000000000d
RBP: 00007ffe8eb3f1f0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000
R13: 0000000000000000 R14: 00007ffe8eb3f3c8 R15: 00007ffe8eb3f3bc
   </TASK>
---[ end trace f43ce73c3c2b13a2 ]---
RIP: 0010:free_irq_cpu_rmap+0x23/0x7d
Code: 0f 1f 80 00 00 00 00 48 85 ff 74 6b 55 48 89 fd 53 66 83 7f 06 00
74 24 31 db 48 8b 55 08 0f b7 c3 48 8b 04 c2 48 85 c0 74 09 <8b> 38 31
f6 e8 c4 0a b8 ff 83 c3 01 66 3b 5d 06 72 de b8 ff ff ff
RSP: 0018:ff384881640eaca0 EFLAGS: 00010282
RAX: e277a58fde16f291 RBX: 0000000000000000 RCX: 0000000000000000
RDX: ff2335e2e20b3600 RSI: 0000000000000000 RDI: ff2335e2e20b3400
RBP: ff2335e2e20b3400 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 00000000ffffffe4 R12: ff384881640ead88
R13: ff2335c3760751e0 R14: ff2335e2e1672200 R15: ff2335c3760751f8
FS:  00007fc32ac22480(0000) GS:ff2335e2d6e00000(0000)
knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f651ab54000 CR3: 00000029f1206003 CR4: 0000000000771ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
PKRU: 55555554
Kernel panic - not syncing: Fatal exception
Kernel Offset: 0x1dc00000 from 0xffffffff81000000 (relocation range:
0xffffffff80000000-0xffffffffbfffffff)
kvm-guest: disable async PF for cpu 0

Fixes: 3354822 ("net/mlx5: Use dynamic msix vectors allocation")
Signed-off-by: Mohith Kumar Thummaluru<mohith.k.kumar.thummaluru@oracle.com>
Tested-by: Mohith Kumar Thummaluru<mohith.k.kumar.thummaluru@oracle.com>
Reviewed-by: Moshe Shemesh <moshe@nvidia.com>
Reviewed-by: Shay Drori <shayd@nvidia.com>
Signed-off-by: Pradyumn Rahar <pradyumn.rahar@oracle.com>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Link: https://patch.msgid.link/1763381768-1234998-1-git-send-email-tariqt@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
mdroth pushed a commit that referenced this pull request Dec 15, 2025
The kernel test has reported:

  BUG: unable to handle page fault for address: fffba000
  #PF: supervisor write access in kernel mode
  #PF: error_code(0x0002) - not-present page
  *pde = 03171067 *pte = 00000000
  Oops: Oops: 0002 [#1]
  CPU: 0 UID: 0 PID: 1 Comm: swapper/0 Tainted: G                T   6.18.0-rc2-00031-gec7f31b2a2d3 #1 NONE  a1d066dfe789f54bc7645c7989957d2bdee593ca
  Tainted: [T]=RANDSTRUCT
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
  EIP: memset (arch/x86/include/asm/string_32.h:168 arch/x86/lib/memcpy_32.c:17)
  Code: a5 8b 4d f4 83 e1 03 74 02 f3 a4 83 c4 04 5e 5f 5d 2e e9 73 41 01 00 90 90 90 3e 8d 74 26 00 55 89 e5 57 56 89 c6 89 d0 89 f7 <f3> aa 89 f0 5e 5f 5d 2e e9 53 41 01 00 cc cc cc 55 89 e5 53 57 56
  EAX: 0000006b EBX: 00000015 ECX: 001fefff EDX: 0000006b
  ESI: fffb9000 EDI: fffba000 EBP: c611fbf0 ESP: c611fbe8
  DS: 007b ES: 007b FS: 0000 GS: 0000 SS: 0068 EFLAGS: 00010287
  CR0: 80050033 CR2: fffba000 CR3: 0316e000 CR4: 00040690
  Call Trace:
   poison_element (mm/mempool.c:83 mm/mempool.c:102)
   mempool_init_node (mm/mempool.c:142 mm/mempool.c:226)
   mempool_init_noprof (mm/mempool.c:250 (discriminator 1))
   ? mempool_alloc_pages (mm/mempool.c:640)
   bio_integrity_initfn (block/bio-integrity.c:483 (discriminator 8))
   ? mempool_alloc_pages (mm/mempool.c:640)
   do_one_initcall (init/main.c:1283)

Christoph found out this is due to the poisoning code not dealing
properly with CONFIG_HIGHMEM because only the first page is mapped but
then the whole potentially high-order page is accessed.

We could give up on HIGHMEM here, but it's straightforward to fix this
with a loop that's mapping, poisoning or checking and unmapping
individual pages.

Reported-by: kernel test robot <oliver.sang@intel.com>
Closes: https://lore.kernel.org/oe-lkp/202511111411.9ebfa1ba-lkp@intel.com
Analyzed-by: Christoph Hellwig <hch@lst.de>
Fixes: bdfedb7 ("mm, mempool: poison elements backed by slab allocator")
Cc: stable@vger.kernel.org
Tested-by: kernel test robot <oliver.sang@intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://patch.msgid.link/20251113-mempool-poison-v1-1-233b3ef984c3@suse.cz
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
mdroth pushed a commit that referenced this pull request Dec 15, 2025
nvme_fc_delete_assocation() waits for pending I/O to complete before
returning, and an error can cause ->ioerr_work to be queued after
cancel_work_sync() had been called.  Move the call to cancel_work_sync() to
be after nvme_fc_delete_association() to ensure ->ioerr_work is not running
when the nvme_fc_ctrl object is freed.  Otherwise the following can occur:

[ 1135.911754] list_del corruption, ff2d24c8093f31f8->next is NULL
[ 1135.917705] ------------[ cut here ]------------
[ 1135.922336] kernel BUG at lib/list_debug.c:52!
[ 1135.926784] Oops: invalid opcode: 0000 [#1] SMP NOPTI
[ 1135.931851] CPU: 48 UID: 0 PID: 726 Comm: kworker/u449:23 Kdump: loaded Not tainted 6.12.0 #1 PREEMPT(voluntary)
[ 1135.943490] Hardware name: Dell Inc. PowerEdge R660/0HGTK9, BIOS 2.5.4 01/16/2025
[ 1135.950969] Workqueue:  0x0 (nvme-wq)
[ 1135.954673] RIP: 0010:__list_del_entry_valid_or_report.cold+0xf/0x6f
[ 1135.961041] Code: c7 c7 98 68 72 94 e8 26 45 fe ff 0f 0b 48 c7 c7 70 68 72 94 e8 18 45 fe ff 0f 0b 48 89 fe 48 c7 c7 80 69 72 94 e8 07 45 fe ff <0f> 0b 48 89 d1 48 c7 c7 a0 6a 72 94 48 89 c2 e8 f3 44 fe ff 0f 0b
[ 1135.979788] RSP: 0018:ff579b19482d3e50 EFLAGS: 00010046
[ 1135.985015] RAX: 0000000000000033 RBX: ff2d24c8093f31f0 RCX: 0000000000000000
[ 1135.992148] RDX: 0000000000000000 RSI: ff2d24d6bfa1d0c0 RDI: ff2d24d6bfa1d0c0
[ 1135.999278] RBP: ff2d24c8093f31f8 R08: 0000000000000000 R09: ffffffff951e2b08
[ 1136.006413] R10: ffffffff95122ac8 R11: 0000000000000003 R12: ff2d24c78697c100
[ 1136.013546] R13: fffffffffffffff8 R14: 0000000000000000 R15: ff2d24c78697c0c0
[ 1136.020677] FS:  0000000000000000(0000) GS:ff2d24d6bfa00000(0000) knlGS:0000000000000000
[ 1136.028765] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 1136.034510] CR2: 00007fd207f90b80 CR3: 000000163ea22003 CR4: 0000000000f73ef0
[ 1136.041641] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 1136.048776] DR3: 0000000000000000 DR6: 00000000fffe07f0 DR7: 0000000000000400
[ 1136.055910] PKRU: 55555554
[ 1136.058623] Call Trace:
[ 1136.061074]  <TASK>
[ 1136.063179]  ? show_trace_log_lvl+0x1b0/0x2f0
[ 1136.067540]  ? show_trace_log_lvl+0x1b0/0x2f0
[ 1136.071898]  ? move_linked_works+0x4a/0xa0
[ 1136.075998]  ? __list_del_entry_valid_or_report.cold+0xf/0x6f
[ 1136.081744]  ? __die_body.cold+0x8/0x12
[ 1136.085584]  ? die+0x2e/0x50
[ 1136.088469]  ? do_trap+0xca/0x110
[ 1136.091789]  ? do_error_trap+0x65/0x80
[ 1136.095543]  ? __list_del_entry_valid_or_report.cold+0xf/0x6f
[ 1136.101289]  ? exc_invalid_op+0x50/0x70
[ 1136.105127]  ? __list_del_entry_valid_or_report.cold+0xf/0x6f
[ 1136.110874]  ? asm_exc_invalid_op+0x1a/0x20
[ 1136.115059]  ? __list_del_entry_valid_or_report.cold+0xf/0x6f
[ 1136.120806]  move_linked_works+0x4a/0xa0
[ 1136.124733]  worker_thread+0x216/0x3a0
[ 1136.128485]  ? __pfx_worker_thread+0x10/0x10
[ 1136.132758]  kthread+0xfa/0x240
[ 1136.135904]  ? __pfx_kthread+0x10/0x10
[ 1136.139657]  ret_from_fork+0x31/0x50
[ 1136.143236]  ? __pfx_kthread+0x10/0x10
[ 1136.146988]  ret_from_fork_asm+0x1a/0x30
[ 1136.150915]  </TASK>

Fixes: 19fce04 ("nvme-fc: avoid calling _nvme_fc_abort_outstanding_ios from interrupt context")
Cc: stable@vger.kernel.org
Tested-by: Marco Patalano <mpatalan@redhat.com>
Reviewed-by: Justin Tee <justin.tee@broadcom.com>
Signed-off-by: Ewan D. Milne <emilne@redhat.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>
mdroth pushed a commit that referenced this pull request Dec 15, 2025
If the allocation of tl_hba->sh fails in tcm_loop_driver_probe() and we
attempt to dereference it in tcm_loop_tpg_address_show() we will get a
segfault, see below for an example. So, check tl_hba->sh before
dereferencing it.

  Unable to allocate struct scsi_host
  BUG: kernel NULL pointer dereference, address: 0000000000000194
  #PF: supervisor read access in kernel mode
  #PF: error_code(0x0000) - not-present page
  PGD 0 P4D 0
  Oops: 0000 [#1] PREEMPT SMP NOPTI
  CPU: 1 PID: 8356 Comm: tokio-runtime-w Not tainted 6.6.104.2-4.azl3 #1
  Hardware name: Microsoft Corporation Virtual Machine/Virtual Machine, BIOS Hyper-V UEFI Release v4.1 09/28/2024
  RIP: 0010:tcm_loop_tpg_address_show+0x2e/0x50 [tcm_loop]
...
  Call Trace:
   <TASK>
   configfs_read_iter+0x12d/0x1d0 [configfs]
   vfs_read+0x1b5/0x300
   ksys_read+0x6f/0xf0
...

Cc: stable@vger.kernel.org
Fixes: 2628b35 ("tcm_loop: Show address of tpg in configfs")
Signed-off-by: Hamza Mahfooz <hamzamahfooz@linux.microsoft.com>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Allen Pais <apais@linux.microsoft.com>
Link: https://patch.msgid.link/1762370746-6304-1-git-send-email-hamzamahfooz@linux.microsoft.com
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
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