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mcgrof pushed a commit that referenced this pull request Oct 15, 2024
Attaching SST PCI device to VM causes "BUG: KASAN: slab-out-of-bounds".
kasan report:
[   19.411889] ==================================================================
[   19.413702] BUG: KASAN: slab-out-of-bounds in _isst_if_get_pci_dev+0x3d5/0x400 [isst_if_common]
[   19.415634] Read of size 8 at addr ffff888829e65200 by task cpuhp/16/113
[   19.417368]
[   19.418627] CPU: 16 PID: 113 Comm: cpuhp/16 Tainted: G            E      6.9.0 #10
[   19.420435] Hardware name: VMware, Inc. VMware20,1/440BX Desktop Reference Platform, BIOS VMW201.00V.20192059.B64.2207280713 07/28/2022
[   19.422687] Call Trace:
[   19.424091]  <TASK>
[   19.425448]  dump_stack_lvl+0x5d/0x80
[   19.426963]  ? _isst_if_get_pci_dev+0x3d5/0x400 [isst_if_common]
[   19.428694]  print_report+0x19d/0x52e
[   19.430206]  ? __pfx__raw_spin_lock_irqsave+0x10/0x10
[   19.431837]  ? _isst_if_get_pci_dev+0x3d5/0x400 [isst_if_common]
[   19.433539]  kasan_report+0xf0/0x170
[   19.435019]  ? _isst_if_get_pci_dev+0x3d5/0x400 [isst_if_common]
[   19.436709]  _isst_if_get_pci_dev+0x3d5/0x400 [isst_if_common]
[   19.438379]  ? __pfx_sched_clock_cpu+0x10/0x10
[   19.439910]  isst_if_cpu_online+0x406/0x58f [isst_if_common]
[   19.441573]  ? __pfx_isst_if_cpu_online+0x10/0x10 [isst_if_common]
[   19.443263]  ? ttwu_queue_wakelist+0x2c1/0x360
[   19.444797]  cpuhp_invoke_callback+0x221/0xec0
[   19.446337]  cpuhp_thread_fun+0x21b/0x610
[   19.447814]  ? __pfx_cpuhp_thread_fun+0x10/0x10
[   19.449354]  smpboot_thread_fn+0x2e7/0x6e0
[   19.450859]  ? __pfx_smpboot_thread_fn+0x10/0x10
[   19.452405]  kthread+0x29c/0x350
[   19.453817]  ? __pfx_kthread+0x10/0x10
[   19.455253]  ret_from_fork+0x31/0x70
[   19.456685]  ? __pfx_kthread+0x10/0x10
[   19.458114]  ret_from_fork_asm+0x1a/0x30
[   19.459573]  </TASK>
[   19.460853]
[   19.462055] Allocated by task 1198:
[   19.463410]  kasan_save_stack+0x30/0x50
[   19.464788]  kasan_save_track+0x14/0x30
[   19.466139]  __kasan_kmalloc+0xaa/0xb0
[   19.467465]  __kmalloc+0x1cd/0x470
[   19.468748]  isst_if_cdev_register+0x1da/0x350 [isst_if_common]
[   19.470233]  isst_if_mbox_init+0x108/0xff0 [isst_if_mbox_msr]
[   19.471670]  do_one_initcall+0xa4/0x380
[   19.472903]  do_init_module+0x238/0x760
[   19.474105]  load_module+0x5239/0x6f00
[   19.475285]  init_module_from_file+0xd1/0x130
[   19.476506]  idempotent_init_module+0x23b/0x650
[   19.477725]  __x64_sys_finit_module+0xbe/0x130
[   19.476506]  idempotent_init_module+0x23b/0x650
[   19.477725]  __x64_sys_finit_module+0xbe/0x130
[   19.478920]  do_syscall_64+0x82/0x160
[   19.480036]  entry_SYSCALL_64_after_hwframe+0x76/0x7e
[   19.481292]
[   19.482205] The buggy address belongs to the object at ffff888829e65000
 which belongs to the cache kmalloc-512 of size 512
[   19.484818] The buggy address is located 0 bytes to the right of
 allocated 512-byte region [ffff888829e65000, ffff888829e65200)
[   19.487447]
[   19.488328] The buggy address belongs to the physical page:
[   19.489569] page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888829e60c00 pfn:0x829e60
[   19.491140] head: order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0
[   19.492466] anon flags: 0x57ffffc0000840(slab|head|node=1|zone=2|lastcpupid=0x1fffff)
[   19.493914] page_type: 0xffffffff()
[   19.494988] raw: 0057ffffc0000840 ffff88810004cc80 0000000000000000 0000000000000001
[   19.496451] raw: ffff888829e60c00 0000000080200018 00000001ffffffff 0000000000000000
[   19.497906] head: 0057ffffc0000840 ffff88810004cc80 0000000000000000 0000000000000001
[   19.499379] head: ffff888829e60c00 0000000080200018 00000001ffffffff 0000000000000000
[   19.500844] head: 0057ffffc0000003 ffffea0020a79801 ffffea0020a79848 00000000ffffffff
[   19.502316] head: 0000000800000000 0000000000000000 00000000ffffffff 0000000000000000
[   19.503784] page dumped because: kasan: bad access detected
[   19.505058]
[   19.505970] Memory state around the buggy address:
[   19.507172]  ffff888829e65100: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[   19.508599]  ffff888829e65180: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[   19.510013] >ffff888829e65200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[   19.510014]                    ^
[   19.510016]  ffff888829e65280: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[   19.510018]  ffff888829e65300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[   19.515367] ==================================================================

The reason for this error is physical_package_ids assigned by VMware VMM
are not continuous and have gaps. This will cause value returned by
topology_physical_package_id() to be more than topology_max_packages().

Here the allocation uses topology_max_packages(). The call to
topology_max_packages() returns maximum logical package ID not physical
ID. Hence use topology_logical_package_id() instead of
topology_physical_package_id().

Fixes: 9a1aac8 ("platform/x86: ISST: PUNIT device mapping with Sub-NUMA clustering")
Cc: stable@vger.kernel.org
Acked-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Zach Wade <zachwade.k@gmail.com>
Link: https://lore.kernel.org/r/20240923144508.1764-1-zachwade.k@gmail.com
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
@computexpresslink computexpresslink closed this by deleting the head repository Oct 16, 2024
modules-kpd-app bot pushed a commit that referenced this pull request Dec 16, 2024
syzkaller reported a warning in __sk_skb_reason_drop().

Commit 61b95c7 ("net: ip: make ip_route_input_rcu() return
drop reasons") missed a path where -EINVAL is returned.

Then, the cited commit started to trigger the warning with the
invalid error.

Let's fix it by returning SKB_DROP_REASON_NOT_SPECIFIED.

[0]:
WARNING: CPU: 0 PID: 10 at net/core/skbuff.c:1216 __sk_skb_reason_drop net/core/skbuff.c:1216 [inline]
WARNING: CPU: 0 PID: 10 at net/core/skbuff.c:1216 sk_skb_reason_drop+0x97/0x1b0 net/core/skbuff.c:1241
Modules linked in:
CPU: 0 UID: 0 PID: 10 Comm: kworker/0:1 Not tainted 6.12.0-10686-gbb18265c3aba #10 1c308307628619808b5a4a0495c4aab5637b0551
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
Workqueue: wg-crypt-wg2 wg_packet_decrypt_worker
RIP: 0010:__sk_skb_reason_drop net/core/skbuff.c:1216 [inline]
RIP: 0010:sk_skb_reason_drop+0x97/0x1b0 net/core/skbuff.c:1241
Code: 5d 41 5c 41 5d 41 5e e9 e7 9e 95 fd e8 e2 9e 95 fd 31 ff 44 89 e6 e8 58 a1 95 fd 45 85 e4 0f 85 a2 00 00 00 e8 ca 9e 95 fd 90 <0f> 0b 90 e8 c1 9e 95 fd 44 89 e6 bf 01 00 00 00 e8 34 a1 95 fd 41
RSP: 0018:ffa0000000007650 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 000000000000ffff RCX: ffffffff83bc3592
RDX: ff110001002a0000 RSI: ffffffff83bc34d6 RDI: 0000000000000007
RBP: ff11000109ee85f0 R08: 0000000000000001 R09: ffe21c00213dd0da
R10: 000000000000ffff R11: 0000000000000000 R12: 00000000ffffffea
R13: 0000000000000000 R14: ff11000109ee86d4 R15: ff11000109ee8648
FS:  0000000000000000(0000) GS:ff1100011a000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020177000 CR3: 0000000108a3d006 CR4: 0000000000771ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe07f0 DR7: 0000000000000600
PKRU: 55555554
Call Trace:
 <IRQ>
 kfree_skb_reason include/linux/skbuff.h:1263 [inline]
 ip_rcv_finish_core.constprop.0+0x896/0x2320 net/ipv4/ip_input.c:424
 ip_list_rcv_finish.constprop.0+0x1b2/0x710 net/ipv4/ip_input.c:610
 ip_sublist_rcv net/ipv4/ip_input.c:636 [inline]
 ip_list_rcv+0x34a/0x460 net/ipv4/ip_input.c:670
 __netif_receive_skb_list_ptype net/core/dev.c:5715 [inline]
 __netif_receive_skb_list_core+0x536/0x900 net/core/dev.c:5762
 __netif_receive_skb_list net/core/dev.c:5814 [inline]
 netif_receive_skb_list_internal+0x77c/0xdc0 net/core/dev.c:5905
 gro_normal_list include/net/gro.h:515 [inline]
 gro_normal_list include/net/gro.h:511 [inline]
 napi_complete_done+0x219/0x8c0 net/core/dev.c:6256
 wg_packet_rx_poll+0xbff/0x1e40 drivers/net/wireguard/receive.c:488
 __napi_poll.constprop.0+0xb3/0x530 net/core/dev.c:6877
 napi_poll net/core/dev.c:6946 [inline]
 net_rx_action+0x9eb/0xe30 net/core/dev.c:7068
 handle_softirqs+0x1ac/0x740 kernel/softirq.c:554
 do_softirq kernel/softirq.c:455 [inline]
 do_softirq+0x48/0x80 kernel/softirq.c:442
 </IRQ>
 <TASK>
 __local_bh_enable_ip+0xed/0x110 kernel/softirq.c:382
 spin_unlock_bh include/linux/spinlock.h:396 [inline]
 ptr_ring_consume_bh include/linux/ptr_ring.h:367 [inline]
 wg_packet_decrypt_worker+0x3ba/0x580 drivers/net/wireguard/receive.c:499
 process_one_work+0x940/0x1a70 kernel/workqueue.c:3229
 process_scheduled_works kernel/workqueue.c:3310 [inline]
 worker_thread+0x639/0xe30 kernel/workqueue.c:3391
 kthread+0x283/0x350 kernel/kthread.c:389
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:244
 </TASK>

Fixes: 82d9983 ("net: ip: make ip_route_input_noref() return drop reasons")
Reported-by: syzkaller <syzkaller@googlegroups.com>
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://patch.msgid.link/20241206020715.80207-1-kuniyu@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
modules-kpd-app bot pushed a commit that referenced this pull request Feb 4, 2025
libtraceevent parses and returns an array of argument fields, sometimes
larger than RAW_SYSCALL_ARGS_NUM (6) because it includes "__syscall_nr",
idx will traverse to index 6 (7th element) whereas sc->fmt->arg holds 6
elements max, creating an out-of-bounds access. This runtime error is
found by UBsan. The error message:

  $ sudo UBSAN_OPTIONS=print_stacktrace=1 ./perf trace -a --max-events=1
  builtin-trace.c:1966:35: runtime error: index 6 out of bounds for type 'syscall_arg_fmt [6]'
    #0 0x5c04956be5fe in syscall__alloc_arg_fmts /home/howard/hw/linux-perf/tools/perf/builtin-trace.c:1966
    #1 0x5c04956c0510 in trace__read_syscall_info /home/howard/hw/linux-perf/tools/perf/builtin-trace.c:2110
    #2 0x5c04956c372b in trace__syscall_info /home/howard/hw/linux-perf/tools/perf/builtin-trace.c:2436
    #3 0x5c04956d2f39 in trace__init_syscalls_bpf_prog_array_maps /home/howard/hw/linux-perf/tools/perf/builtin-trace.c:3897
    #4 0x5c04956d6d25 in trace__run /home/howard/hw/linux-perf/tools/perf/builtin-trace.c:4335
    #5 0x5c04956e112e in cmd_trace /home/howard/hw/linux-perf/tools/perf/builtin-trace.c:5502
    #6 0x5c04956eda7d in run_builtin /home/howard/hw/linux-perf/tools/perf/perf.c:351
    #7 0x5c04956ee0a8 in handle_internal_command /home/howard/hw/linux-perf/tools/perf/perf.c:404
    #8 0x5c04956ee37f in run_argv /home/howard/hw/linux-perf/tools/perf/perf.c:448
    #9 0x5c04956ee8e9 in main /home/howard/hw/linux-perf/tools/perf/perf.c:556
    #10 0x79eb3622a3b7 in __libc_start_call_main ../sysdeps/nptl/libc_start_call_main.h:58
    #11 0x79eb3622a47a in __libc_start_main_impl ../csu/libc-start.c:360
    #12 0x5c04955422d4 in _start (/home/howard/hw/linux-perf/tools/perf/perf+0x4e02d4) (BuildId: 5b6cab2d59e96a4341741765ad6914a4d784dbc6)

     0.000 ( 0.014 ms): Chrome_ChildIO/117244 write(fd: 238, buf: !, count: 1)                                      = 1

Fixes: 5e58fcf ("perf trace: Allow allocating sc->arg_fmt even without the syscall tracepoint")
Signed-off-by: Howard Chu <howardchu95@gmail.com>
Link: https://lore.kernel.org/r/20250122025519.361873-1-howardchu95@gmail.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
modules-kpd-app bot pushed a commit that referenced this pull request May 5, 2025
When the size of the range invalidated is larger than
rounddown_pow_of_two(ULONG_MAX),
The function macro roundup_pow_of_two(length) will hit an out-of-bounds
shift [1].

Use a full TLB invalidation for such cases.
v2:
- Use a define for the range size limit over which we use a full
  TLB invalidation. (Lucas)
- Use a better calculation of the limit.

[1]:
[   39.202421] ------------[ cut here ]------------
[   39.202657] UBSAN: shift-out-of-bounds in ./include/linux/log2.h:57:13
[   39.202673] shift exponent 64 is too large for 64-bit type 'long unsigned int'
[   39.202688] CPU: 8 UID: 0 PID: 3129 Comm: xe_exec_system_ Tainted: G     U             6.14.0+ #10
[   39.202690] Tainted: [U]=USER
[   39.202690] Hardware name: ASUS System Product Name/PRIME B560M-A AC, BIOS 2001 02/01/2023
[   39.202691] Call Trace:
[   39.202692]  <TASK>
[   39.202695]  dump_stack_lvl+0x6e/0xa0
[   39.202699]  ubsan_epilogue+0x5/0x30
[   39.202701]  __ubsan_handle_shift_out_of_bounds.cold+0x61/0xe6
[   39.202705]  xe_gt_tlb_invalidation_range.cold+0x1d/0x3a [xe]
[   39.202800]  ? find_held_lock+0x2b/0x80
[   39.202803]  ? mark_held_locks+0x40/0x70
[   39.202806]  xe_svm_invalidate+0x459/0x700 [xe]
[   39.202897]  drm_gpusvm_notifier_invalidate+0x4d/0x70 [drm_gpusvm]
[   39.202900]  __mmu_notifier_release+0x1f5/0x270
[   39.202905]  exit_mmap+0x40e/0x450
[   39.202912]  __mmput+0x45/0x110
[   39.202914]  exit_mm+0xc5/0x130
[   39.202916]  do_exit+0x21c/0x500
[   39.202918]  ? lockdep_hardirqs_on_prepare+0xdb/0x190
[   39.202920]  do_group_exit+0x36/0xa0
[   39.202922]  get_signal+0x8f8/0x900
[   39.202926]  arch_do_signal_or_restart+0x35/0x100
[   39.202930]  syscall_exit_to_user_mode+0x1fc/0x290
[   39.202932]  do_syscall_64+0xa1/0x180
[   39.202934]  ? do_user_addr_fault+0x59f/0x8a0
[   39.202937]  ? lock_release+0xd2/0x2a0
[   39.202939]  ? do_user_addr_fault+0x5a9/0x8a0
[   39.202942]  ? trace_hardirqs_off+0x4b/0xc0
[   39.202944]  ? clear_bhb_loop+0x25/0x80
[   39.202946]  ? clear_bhb_loop+0x25/0x80
[   39.202947]  ? clear_bhb_loop+0x25/0x80
[   39.202950]  entry_SYSCALL_64_after_hwframe+0x76/0x7e
[   39.202952] RIP: 0033:0x7fa945e543e1
[   39.202961] Code: Unable to access opcode bytes at 0x7fa945e543b7.
[   39.202962] RSP: 002b:00007ffca8fb4170 EFLAGS: 00000293
[   39.202963] RAX: 000000000000003d RBX: 0000000000000000 RCX: 00007fa945e543e3
[   39.202964] RDX: 0000000000000000 RSI: 00007ffca8fb41ac RDI: 00000000ffffffff
[   39.202964] RBP: 00007ffca8fb4190 R08: 0000000000000000 R09: 00007fa945f600a0
[   39.202965] R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000
[   39.202966] R13: 00007fa9460dd310 R14: 00007ffca8fb41ac R15: 0000000000000000
[   39.202970]  </TASK>
[   39.202970] ---[ end trace ]---

Fixes: 332dd01 ("drm/xe: Add range based TLB invalidations")
Cc: Matthew Brost <matthew.brost@intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: <stable@vger.kernel.org> # v6.8+
Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: Lucas De Marchi <lucas.demarchi@intel.com> #v1
Link: https://lore.kernel.org/r/20250326151634.36916-1-thomas.hellstrom@linux.intel.com
(cherry picked from commit b88f48f)
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
dkruces pushed a commit that referenced this pull request Aug 25, 2025
Both jbd2_log_do_checkpoint() and jbd2_journal_shrink_checkpoint_list()
periodically release j_list_lock after processing a batch of buffers to
avoid long hold times on the j_list_lock. However, since both functions
contend for j_list_lock, the combined time spent waiting and processing
can be significant.

jbd2_journal_shrink_checkpoint_list() explicitly calls cond_resched() when
need_resched() is true to avoid softlockups during prolonged operations.
But jbd2_log_do_checkpoint() only exits its loop when need_resched() is
true, relying on potentially sleeping functions like __flush_batch() or
wait_on_buffer() to trigger rescheduling. If those functions do not sleep,
the kernel may hit a softlockup.

watchdog: BUG: soft lockup - CPU#3 stuck for 156s! [kworker/u129:2:373]
CPU: 3 PID: 373 Comm: kworker/u129:2 Kdump: loaded Not tainted 6.6.0+ #10
Hardware name: Huawei TaiShan 2280 /BC11SPCD, BIOS 1.27 06/13/2017
Workqueue: writeback wb_workfn (flush-7:2)
pstate: 20000005 (nzCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : native_queued_spin_lock_slowpath+0x358/0x418
lr : jbd2_log_do_checkpoint+0x31c/0x438 [jbd2]
Call trace:
 native_queued_spin_lock_slowpath+0x358/0x418
 jbd2_log_do_checkpoint+0x31c/0x438 [jbd2]
 __jbd2_log_wait_for_space+0xfc/0x2f8 [jbd2]
 add_transaction_credits+0x3bc/0x418 [jbd2]
 start_this_handle+0xf8/0x560 [jbd2]
 jbd2__journal_start+0x118/0x228 [jbd2]
 __ext4_journal_start_sb+0x110/0x188 [ext4]
 ext4_do_writepages+0x3dc/0x740 [ext4]
 ext4_writepages+0xa4/0x190 [ext4]
 do_writepages+0x94/0x228
 __writeback_single_inode+0x48/0x318
 writeback_sb_inodes+0x204/0x590
 __writeback_inodes_wb+0x54/0xf8
 wb_writeback+0x2cc/0x3d8
 wb_do_writeback+0x2e0/0x2f8
 wb_workfn+0x80/0x2a8
 process_one_work+0x178/0x3e8
 worker_thread+0x234/0x3b8
 kthread+0xf0/0x108
 ret_from_fork+0x10/0x20

So explicitly call cond_resched() in jbd2_log_do_checkpoint() to avoid
softlockup.

Cc: stable@kernel.org
Signed-off-by: Baokun Li <libaokun1@huawei.com>
Link: https://patch.msgid.link/20250812063752.912130-1-libaokun@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
dkruces pushed a commit that referenced this pull request Aug 25, 2025
…dlock

When a user creates a dualpi2 qdisc it automatically sets a timer. This
timer will run constantly and update the qdisc's probability field.
The issue is that the timer acquires the qdisc root lock and runs in
hardirq. The qdisc root lock is also acquired in dev.c whenever a packet
arrives for this qdisc. Since the dualpi2 timer callback runs in hardirq,
it may interrupt the packet processing running in softirq. If that happens
and it runs on the same CPU, it will acquire the same lock and cause a
deadlock. The following splat shows up when running a kernel compiled with
lock debugging:

[  +0.000224] WARNING: inconsistent lock state
[  +0.000224] 6.16.0+ #10 Not tainted
[  +0.000169] --------------------------------
[  +0.000029] inconsistent {IN-HARDIRQ-W} -> {HARDIRQ-ON-W} usage.
[  +0.000000] ping/156 [HC0[0]:SC0[2]:HE1:SE0] takes:
[  +0.000000] ffff897841242110 (&sch->root_lock_key){?.-.}-{3:3}, at: __dev_queue_xmit+0x86d/0x1140
[  +0.000000] {IN-HARDIRQ-W} state was registered at:
[  +0.000000]   lock_acquire.part.0+0xb6/0x220
[  +0.000000]   _raw_spin_lock+0x31/0x80
[  +0.000000]   dualpi2_timer+0x6f/0x270
[  +0.000000]   __hrtimer_run_queues+0x1c5/0x360
[  +0.000000]   hrtimer_interrupt+0x115/0x260
[  +0.000000]   __sysvec_apic_timer_interrupt+0x6d/0x1a0
[  +0.000000]   sysvec_apic_timer_interrupt+0x6e/0x80
[  +0.000000]   asm_sysvec_apic_timer_interrupt+0x1a/0x20
[  +0.000000]   pv_native_safe_halt+0xf/0x20
[  +0.000000]   default_idle+0x9/0x10
[  +0.000000]   default_idle_call+0x7e/0x1e0
[  +0.000000]   do_idle+0x1e8/0x250
[  +0.000000]   cpu_startup_entry+0x29/0x30
[  +0.000000]   rest_init+0x151/0x160
[  +0.000000]   start_kernel+0x6f3/0x700
[  +0.000000]   x86_64_start_reservations+0x24/0x30
[  +0.000000]   x86_64_start_kernel+0xc8/0xd0
[  +0.000000]   common_startup_64+0x13e/0x148
[  +0.000000] irq event stamp: 6884
[  +0.000000] hardirqs last  enabled at (6883): [<ffffffffa75700b3>] neigh_resolve_output+0x223/0x270
[  +0.000000] hardirqs last disabled at (6882): [<ffffffffa7570078>] neigh_resolve_output+0x1e8/0x270
[  +0.000000] softirqs last  enabled at (6880): [<ffffffffa757006b>] neigh_resolve_output+0x1db/0x270
[  +0.000000] softirqs last disabled at (6884): [<ffffffffa755b533>] __dev_queue_xmit+0x73/0x1140
[  +0.000000]
              other info that might help us debug this:
[  +0.000000]  Possible unsafe locking scenario:

[  +0.000000]        CPU0
[  +0.000000]        ----
[  +0.000000]   lock(&sch->root_lock_key);
[  +0.000000]   <Interrupt>
[  +0.000000]     lock(&sch->root_lock_key);
[  +0.000000]
               *** DEADLOCK ***

[  +0.000000] 4 locks held by ping/156:
[  +0.000000]  #0: ffff897842332e08 (sk_lock-AF_INET){+.+.}-{0:0}, at: raw_sendmsg+0x41e/0xf40
[  +0.000000]  #1: ffffffffa816f880 (rcu_read_lock){....}-{1:3}, at: ip_output+0x2c/0x190
[  +0.000000]  #2: ffffffffa816f880 (rcu_read_lock){....}-{1:3}, at: ip_finish_output2+0xad/0x950
[  +0.000000]  #3: ffffffffa816f840 (rcu_read_lock_bh){....}-{1:3}, at: __dev_queue_xmit+0x73/0x1140

I am able to reproduce it consistently when running the following:

tc qdisc add dev lo handle 1: root dualpi2
ping -f 127.0.0.1

To fix it, make the timer run in softirq.

Fixes: 320d031 ("sched: Struct definition and parsing of dualpi2 qdisc")
Reviewed-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Victor Nogueira <victor@mojatatu.com>
Link: https://patch.msgid.link/20250815135317.664993-1-victor@mojatatu.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
dkruces pushed a commit that referenced this pull request Sep 29, 2025
smc_lo_register_dmb() allocates DMB buffers with kzalloc(), which are
later passed to get_page() in smc_rx_splice(). Since kmalloc memory is
not page-backed, this triggers WARN_ON_ONCE() in get_page() and prevents
holding a refcount on the buffer. This can lead to use-after-free if
the memory is released before splice_to_pipe() completes.

Use folio_alloc() instead, ensuring DMBs are page-backed and safe for
get_page().

WARNING: CPU: 18 PID: 12152 at ./include/linux/mm.h:1330 smc_rx_splice+0xaf8/0xe20 [smc]
CPU: 18 UID: 0 PID: 12152 Comm: smcapp Kdump: loaded Not tainted 6.17.0-rc3-11705-g9cf4672ecfee #10 NONE
Hardware name: IBM 3931 A01 704 (z/VM 7.4.0)
Krnl PSW : 0704e00180000000 000793161032696c (smc_rx_splice+0xafc/0xe20 [smc])
           R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 CC:2 PM:0 RI:0 EA:3
Krnl GPRS: 0000000000000000 001cee80007d3001 00077400000000f8 0000000000000005
           0000000000000001 001cee80007d3006 0007740000001000 001c000000000000
           000000009b0c99e0 0000000000001000 001c0000000000f8 001c000000000000
           000003ffcc6f7c88 0007740003e98000 0007931600000005 000792969b2ff7b8
Krnl Code: 0007931610326960: af000000		mc	0,0
           0007931610326964: a7f4ff43		brc	15,00079316103267ea
          #0007931610326968: af000000		mc	0,0
          >000793161032696c: a7f4ff3f		brc	15,00079316103267ea
           0007931610326970: e320f1000004	lg	%r2,256(%r15)
           0007931610326976: c0e53fd1b5f5	brasl	%r14,000793168fd5d560
           000793161032697c: a7f4fbb5		brc	15,00079316103260e6
           0007931610326980: b904002b		lgr	%r2,%r11
Call Trace:
 smc_rx_splice+0xafc/0xe20 [smc]
 smc_rx_splice+0x756/0xe20 [smc])
 smc_rx_recvmsg+0xa74/0xe00 [smc]
 smc_splice_read+0x1ce/0x3b0 [smc]
 sock_splice_read+0xa2/0xf0
 do_splice_read+0x198/0x240
 splice_file_to_pipe+0x7e/0x110
 do_splice+0x59e/0xde0
 __do_splice+0x11a/0x2d0
 __s390x_sys_splice+0x140/0x1f0
 __do_syscall+0x122/0x280
 system_call+0x6e/0x90
Last Breaking-Event-Address:
smc_rx_splice+0x960/0xe20 [smc]
---[ end trace 0000000000000000 ]---

Fixes: f7a2207 ("net/smc: implement DMB-related operations of loopback-ism")
Reviewed-by: Mahanta Jambigi <mjambigi@linux.ibm.com>
Signed-off-by: Sidraya Jayagond <sidraya@linux.ibm.com>
Link: https://patch.msgid.link/20250917184220.801066-1-sidraya@linux.ibm.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
dkruces pushed a commit that referenced this pull request Sep 29, 2025
Running sha224_kunit on a KMSAN-enabled kernel results in a crash in
kmsan_internal_set_shadow_origin():

    BUG: unable to handle page fault for address: ffffbc3840291000
    #PF: supervisor read access in kernel mode
    #PF: error_code(0x0000) - not-present page
    PGD 1810067 P4D 1810067 PUD 192d067 PMD 3c17067 PTE 0
    Oops: 0000 [#1] SMP NOPTI
    CPU: 0 UID: 0 PID: 81 Comm: kunit_try_catch Tainted: G                 N  6.17.0-rc3 #10 PREEMPT(voluntary)
    Tainted: [N]=TEST
    Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.17.0-0-gb52ca86e094d-prebuilt.qemu.org 04/01/2014
    RIP: 0010:kmsan_internal_set_shadow_origin+0x91/0x100
    [...]
    Call Trace:
    <TASK>
    __msan_memset+0xee/0x1a0
    sha224_final+0x9e/0x350
    test_hash_buffer_overruns+0x46f/0x5f0
    ? kmsan_get_shadow_origin_ptr+0x46/0xa0
    ? __pfx_test_hash_buffer_overruns+0x10/0x10
    kunit_try_run_case+0x198/0xa00

This occurs when memset() is called on a buffer that is not 4-byte aligned
and extends to the end of a guard page, i.e.  the next page is unmapped.

The bug is that the loop at the end of kmsan_internal_set_shadow_origin()
accesses the wrong shadow memory bytes when the address is not 4-byte
aligned.  Since each 4 bytes are associated with an origin, it rounds the
address and size so that it can access all the origins that contain the
buffer.  However, when it checks the corresponding shadow bytes for a
particular origin, it incorrectly uses the original unrounded shadow
address.  This results in reads from shadow memory beyond the end of the
buffer's shadow memory, which crashes when that memory is not mapped.

To fix this, correctly align the shadow address before accessing the 4
shadow bytes corresponding to each origin.

Link: https://lkml.kernel.org/r/20250911195858.394235-1-ebiggers@kernel.org
Fixes: 2ef3cec ("kmsan: do not wipe out origin when doing partial unpoisoning")
Signed-off-by: Eric Biggers <ebiggers@kernel.org>
Tested-by: Alexander Potapenko <glider@google.com>
Reviewed-by: Alexander Potapenko <glider@google.com>
Cc: Dmitriy Vyukov <dvyukov@google.com>
Cc: Marco Elver <elver@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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