[5.15-velinux] Intel: backport KVM Fix for Clearing SGX EDECCSSA to 5.15

arch/x86/include/asm/cpufeatures.h

@@ -301,6 +301,7 @@
 #define X86_FEATURE_UNRET		(11*32+15) /* "" AMD BTB untrain return */
 #define X86_FEATURE_USE_IBPB_FW		(11*32+16) /* "" Use IBPB during runtime firmware calls */
 #define X86_FEATURE_RSB_VMEXIT_LITE	(11*32+17) /* "" Fill RSB on VM exit when EIBRS is enabled */
+#define X86_FEATURE_SGX_EDECCSSA	(11*32+18) /* "" SGX EDECCSSA user leaf function */
 
 
 #define X86_FEATURE_MSR_TSX_CTRL	(11*32+20) /* "" MSR IA32_TSX_CTRL (Intel) implemented */

arch/x86/include/asm/sgx.h

@@ -97,17 +97,36 @@ enum sgx_miscselect {
  * %SGX_ATTR_EINITTOKENKEY:	Allow to use token signing key that is used to
  *				sign cryptographic tokens that can be passed to
  *				EINIT as an authorization to run an enclave.
+ * %SGX_ATTR_ASYNC_EXIT_NOTIFY:	Allow enclaves to be notified after an
+ *				asynchronous exit has occurred.
  */
 enum sgx_attribute {
-	SGX_ATTR_INIT		= BIT(0),
-	SGX_ATTR_DEBUG		= BIT(1),
-	SGX_ATTR_MODE64BIT	= BIT(2),
-	SGX_ATTR_PROVISIONKEY	= BIT(4),
-	SGX_ATTR_EINITTOKENKEY	= BIT(5),
-	SGX_ATTR_KSS		= BIT(7),
+	SGX_ATTR_INIT		   = BIT(0),
+	SGX_ATTR_DEBUG		   = BIT(1),
+	SGX_ATTR_MODE64BIT	   = BIT(2),
+				  /* BIT(3) is reserved */
+	SGX_ATTR_PROVISIONKEY	   = BIT(4),
+	SGX_ATTR_EINITTOKENKEY	   = BIT(5),
+				  /* BIT(6) is for CET */
+	SGX_ATTR_KSS		   = BIT(7),
+				  /* BIT(8) is reserved */
+				  /* BIT(9) is reserved */
+	SGX_ATTR_ASYNC_EXIT_NOTIFY = BIT(10),
 };
 
-#define SGX_ATTR_RESERVED_MASK	(BIT_ULL(3) | BIT_ULL(6) | GENMASK_ULL(63, 8))
+#define SGX_ATTR_RESERVED_MASK	(BIT_ULL(3) | \
+				 BIT_ULL(6) | \
+				 BIT_ULL(8) | \
+				 BIT_ULL(9) | \
+				 GENMASK_ULL(63, 11))
+
+#define SGX_ATTR_UNPRIV_MASK	(SGX_ATTR_DEBUG	    | \
+				 SGX_ATTR_MODE64BIT | \
+				 SGX_ATTR_KSS	    | \
+				 SGX_ATTR_ASYNC_EXIT_NOTIFY)
+
+#define SGX_ATTR_PRIV_MASK	(SGX_ATTR_PROVISIONKEY	| \
+				 SGX_ATTR_EINITTOKENKEY)
 
 /**
  * struct sgx_secs - SGX Enclave Control Structure (SECS)

arch/x86/kernel/cpu/cpuid-deps.c

@@ -77,6 +77,7 @@ static const struct cpuid_dep cpuid_deps[] = {
 	{ X86_FEATURE_SGX_LC,			X86_FEATURE_SGX	      },
 	{ X86_FEATURE_SGX1,			X86_FEATURE_SGX       },
 	{ X86_FEATURE_SGX2,			X86_FEATURE_SGX1      },
+	{ X86_FEATURE_SGX_EDECCSSA,		X86_FEATURE_SGX1      },
 	{ X86_FEATURE_XFD,			X86_FEATURE_XSAVES    },
 	{ X86_FEATURE_XFD,			X86_FEATURE_XGETBV1   },
 	{ X86_FEATURE_AMX_TILE,			X86_FEATURE_XFD       },

arch/x86/kernel/cpu/scattered.c

@@ -39,6 +39,7 @@ static const struct cpuid_bit cpuid_bits[] = {
 	{ X86_FEATURE_PER_THREAD_MBA,	CPUID_ECX,  0, 0x00000010, 3 },
 	{ X86_FEATURE_SGX1,		CPUID_EAX,  0, 0x00000012, 0 },
 	{ X86_FEATURE_SGX2,		CPUID_EAX,  1, 0x00000012, 0 },
+	{ X86_FEATURE_SGX_EDECCSSA,	CPUID_EAX, 11, 0x00000012, 0 },
 	{ X86_FEATURE_HW_PSTATE,	CPUID_EDX,  7, 0x80000007, 0 },
 	{ X86_FEATURE_CPB,		CPUID_EDX,  9, 0x80000007, 0 },
 	{ X86_FEATURE_PROC_FEEDBACK,    CPUID_EDX, 11, 0x80000007, 0 },

arch/x86/kernel/cpu/sgx/encl.c

@@ -12,6 +12,9 @@
 #include "encls.h"
 #include "sgx.h"
 
+static int sgx_encl_lookup_backing(struct sgx_encl *encl, unsigned long page_index,
+			    struct sgx_backing *backing);
+
 #define PCMDS_PER_PAGE (PAGE_SIZE / sizeof(struct sgx_pcmd))
 /*
  * 32 PCMD entries share a PCMD page. PCMD_FIRST_MASK is used to
@@ -932,7 +935,7 @@ static struct page *sgx_encl_get_backing_page(struct sgx_encl *encl,
 }
 
 /**
- * sgx_encl_get_backing() - Pin the backing storage
+ * __sgx_encl_get_backing() - Pin the backing storage
  * @encl:	an enclave pointer
  * @page_index:	enclave page index
  * @backing:	data for accessing backing storage for the page
@@ -944,7 +947,7 @@ static struct page *sgx_encl_get_backing_page(struct sgx_encl *encl,
  *   0 on success,
  *   -errno otherwise.
  */
-static int sgx_encl_get_backing(struct sgx_encl *encl, unsigned long page_index,
+static int __sgx_encl_get_backing(struct sgx_encl *encl, unsigned long page_index,
 			 struct sgx_backing *backing)
 {
 	pgoff_t page_pcmd_off = sgx_encl_get_backing_page_pcmd_offset(encl, page_index);
@@ -1019,15 +1022,17 @@ static struct mem_cgroup *sgx_encl_get_mem_cgroup(struct sgx_encl *encl)
 }
 
 /**
- * sgx_encl_alloc_backing() - allocate a new backing storage page
+ * sgx_encl_alloc_backing() - create a new backing storage page
  * @encl:	an enclave pointer
  * @page_index:	enclave page index
  * @backing:	data for accessing backing storage for the page
  *
  * When called from ksgxd, sets the active memcg from one of the
  * mms in the enclave's mm_list prior to any backing page allocation,
  * in order to ensure that shmem page allocations are charged to the
- * enclave.
+ * enclave.  Create a backing page for loading data back into an EPC page with
+ * ELDU.  This function takes a reference on a new backing page which
+ * must be dropped with a corresponding call to sgx_encl_put_backing().
  *
  * Return:
  *   0 on success,
@@ -1040,7 +1045,7 @@ int sgx_encl_alloc_backing(struct sgx_encl *encl, unsigned long page_index,
 	struct mem_cgroup *memcg = set_active_memcg(encl_memcg);
 	int ret;
 
-	ret = sgx_encl_get_backing(encl, page_index, backing);
+	ret = __sgx_encl_get_backing(encl, page_index, backing);
 
 	set_active_memcg(memcg);
 	mem_cgroup_put(encl_memcg);
@@ -1058,15 +1063,17 @@ int sgx_encl_alloc_backing(struct sgx_encl *encl, unsigned long page_index,
  * It is the caller's responsibility to ensure that it is appropriate to use
  * sgx_encl_lookup_backing() rather than sgx_encl_alloc_backing(). If lookup is
  * not used correctly, this will cause an allocation which is not accounted for.
+ * This function takes a reference on an existing backing page which must be
+ * dropped with a corresponding call to sgx_encl_put_backing().
  *
  * Return:
  *   0 on success,
  *   -errno otherwise.
  */
-int sgx_encl_lookup_backing(struct sgx_encl *encl, unsigned long page_index,
+static int sgx_encl_lookup_backing(struct sgx_encl *encl, unsigned long page_index,
 			   struct sgx_backing *backing)
 {
-	return sgx_encl_get_backing(encl, page_index, backing);
+	return __sgx_encl_get_backing(encl, page_index, backing);
 }
 
 /**

arch/x86/kernel/cpu/sgx/encl.h

@@ -107,8 +107,6 @@ bool current_is_ksgxd(void);
 void sgx_encl_release(struct kref *ref);
 int sgx_encl_mm_add(struct sgx_encl *encl, struct mm_struct *mm);
 const cpumask_t *sgx_encl_cpumask(struct sgx_encl *encl);
-int sgx_encl_lookup_backing(struct sgx_encl *encl, unsigned long page_index,
-			    struct sgx_backing *backing);
 int sgx_encl_alloc_backing(struct sgx_encl *encl, unsigned long page_index,
 			   struct sgx_backing *backing);
 void sgx_encl_put_backing(struct sgx_backing *backing);

arch/x86/kernel/cpu/sgx/ioctl.c

@@ -111,7 +111,7 @@ static int sgx_encl_create(struct sgx_encl *encl, struct sgx_secs *secs)
 	encl->base = secs->base;
 	encl->size = secs->size;
 	encl->attributes = secs->attributes;
-	encl->attributes_mask = SGX_ATTR_DEBUG | SGX_ATTR_MODE64BIT | SGX_ATTR_KSS;
+	encl->attributes_mask = SGX_ATTR_UNPRIV_MASK;
 
 	/* Set only after completion, as encl->lock has not been taken. */
 	set_bit(SGX_ENCL_CREATED, &encl->flags);

arch/x86/kvm/cpuid.c

@@ -533,7 +533,7 @@ void kvm_set_cpu_caps(void)
 	);
 
 	kvm_cpu_cap_init_scattered(CPUID_12_EAX,
-		SF(SGX1) | SF(SGX2)
+		SF(SGX1) | SF(SGX2) | SF(SGX_EDECCSSA)
 	);
 
 	kvm_cpu_cap_mask(CPUID_8000_0001_ECX,
@@ -919,9 +919,7 @@ static inline int __do_cpuid_func(struct kvm_cpuid_array *array, u32 function)
 		 * userspace.  ATTRIBUTES.XFRM is not adjusted as userspace is
 		 * expected to derive it from supported XCR0.
 		 */
-		entry->eax &= SGX_ATTR_DEBUG | SGX_ATTR_MODE64BIT |
-			      SGX_ATTR_PROVISIONKEY | SGX_ATTR_EINITTOKENKEY |
-			      SGX_ATTR_KSS;
+		entry->eax &= SGX_ATTR_PRIV_MASK | SGX_ATTR_UNPRIV_MASK;
 		entry->ebx &= 0;
 		break;
 	/* Intel PT */

arch/x86/kvm/reverse_cpuid.h

@@ -23,6 +23,7 @@ enum kvm_only_cpuid_leafs {
 /* Intel-defined SGX sub-features, CPUID level 0x12 (EAX). */
 #define KVM_X86_FEATURE_SGX1		KVM_X86_FEATURE(CPUID_12_EAX, 0)
 #define KVM_X86_FEATURE_SGX2		KVM_X86_FEATURE(CPUID_12_EAX, 1)
+#define KVM_X86_FEATURE_SGX_EDECCSSA	KVM_X86_FEATURE(CPUID_12_EAX, 11)
 
 struct cpuid_reg {
 	u32 function;
@@ -81,6 +82,8 @@ static __always_inline u32 __feature_translate(int x86_feature)
 		return KVM_X86_FEATURE_SGX1;
 	else if (x86_feature == X86_FEATURE_SGX2)
 		return KVM_X86_FEATURE_SGX2;
+	else if (x86_feature == X86_FEATURE_SGX_EDECCSSA)
+		return KVM_X86_FEATURE_SGX_EDECCSSA;
 
 	return x86_feature;
 }

tools/testing/selftests/sgx/sigstruct.c

@@ -17,6 +17,12 @@
 #include "defines.h"
 #include "main.h"
 
+/*
+ * FIXME: OpenSSL 3.0 has deprecated some functions. For now just ignore
+ * the warnings.
+ */
+#pragma GCC diagnostic ignored "-Wdeprecated-declarations"
+
 struct q1q2_ctx {
 	BN_CTX *bn_ctx;
 	BIGNUM *m;