UefiCpuPkg/PiSmmCpuDxeSmm: Update mPatchCetSupported set condition

REF:https://bugzilla.tianocore.org/show_bug.cgi?id=3584

Function AsmCpuid should first check the value for Basic CPUID Information.
The fix is to update the mPatchCetSupported judgment statement.

Signed-off-by: Wenxing Hou <wenxing.hou@intel.com>
Reviewed-by: Ray Ni <ray.ni@intel.com>
Cc: Eric Dong   <eric.dong@intel.com>
Cc: Ray Ni      <ray.ni@intel.com>
Cc: Rahul Kumar <rahul1.kumar@intel.com>
Cc: Sheng W     <w.sheng@intel.com>
Cc: Yao Jiewen  <jiewen.yao@intel.com>

1 files changed, 8 insertions, 7 deletions

diff --git a/UefiCpuPkg/PiSmmCpuDxeSmm/SmmProfile.c b/UefiCpuPkg/PiSmmCpuDxeSmm/SmmProfile.c
index d7ed9ab7a7..972bdc2859 100644
--- a/UefiCpuPkg/PiSmmCpuDxeSmm/SmmProfile.c
+++ b/UefiCpuPkg/PiSmmCpuDxeSmm/SmmProfile.c
@@ -985,13 +985,14 @@ CheckFeatureSupported (
   MSR_IA32_MISC_ENABLE_REGISTER  MiscEnableMsr;

 

   if ((PcdGet32 (PcdControlFlowEnforcementPropertyMask) != 0) && mCetSupported) {

-    AsmCpuid (CPUID_EXTENDED_FUNCTION, &RegEax, NULL, NULL, NULL);

-    if (RegEax <= CPUID_EXTENDED_FUNCTION) {

-      mCetSupported = FALSE;

-      PatchInstructionX86 (mPatchCetSupported, mCetSupported, 1);

-    }

-    AsmCpuidEx (CPUID_STRUCTURED_EXTENDED_FEATURE_FLAGS, CPUID_STRUCTURED_EXTENDED_FEATURE_FLAGS_SUB_LEAF_INFO, NULL, NULL, &RegEcx, NULL);

-    if ((RegEcx & CPUID_CET_SS) == 0) {

+    AsmCpuid (CPUID_SIGNATURE, &RegEax, NULL, NULL, NULL);

+    if (RegEax >= CPUID_STRUCTURED_EXTENDED_FEATURE_FLAGS) {

+      AsmCpuidEx (CPUID_STRUCTURED_EXTENDED_FEATURE_FLAGS, CPUID_STRUCTURED_EXTENDED_FEATURE_FLAGS_SUB_LEAF_INFO, NULL, NULL, &RegEcx, NULL);

+      if ((RegEcx & CPUID_CET_SS) == 0) {

+        mCetSupported = FALSE;

+        PatchInstructionX86 (mPatchCetSupported, mCetSupported, 1);

+      }

+    } else {

       mCetSupported = FALSE;

       PatchInstructionX86 (mPatchCetSupported, mCetSupported, 1);

     }