[PATCH v4 10/12] UefiCpuPkg: Fix conditionally uninitialized variables

["Michael Kubacki" <mikuback@linux.microsoft.com>]

From: Michael Kubacki <michael.kubacki@microsoft.com>

Fixes CodeQL alerts for CWE-457:
https://cwe.mitre.org/data/definitions/457.html

Cc: Eric Dong <eric.dong@intel.com>
Cc: Erich McMillan <emcmillan@microsoft.com>
Cc: Michael D Kinney <michael.d.kinney@intel.com>
Cc: Michael Kubacki <mikuback@linux.microsoft.com>
Cc: Rahul Kumar <rahul1.kumar@intel.com>
Cc: Ray Ni <ray.ni@intel.com>
Co-authored-by: Erich McMillan <emcmillan@microsoft.com>
Signed-off-by: Michael Kubacki <michael.kubacki@microsoft.com>
---
 UefiCpuPkg/CpuMpPei/CpuBist.c   | 8 +++++++-
 UefiCpuPkg/CpuMpPei/CpuMpPei.c  | 8 +++++++-
 UefiCpuPkg/CpuMpPei/CpuPaging.c | 9 ++++++++-
 3 files changed, 22 insertions(+), 3 deletions(-)

diff --git a/UefiCpuPkg/CpuMpPei/CpuBist.c b/UefiCpuPkg/CpuMpPei/CpuBist.c
index 7dc93cd784d4..122808139b87 100644
--- a/UefiCpuPkg/CpuMpPei/CpuBist.c
+++ b/UefiCpuPkg/CpuMpPei/CpuBist.c
@@ -175,7 +175,13 @@ CollectBistDataFromPpi (
   EFI_SEC_PLATFORM_INFORMATION_RECORD2  *PlatformInformationRecord2;
   EFI_SEC_PLATFORM_INFORMATION_CPU      *CpuInstanceInHob;
 
-  MpInitLibGetNumberOfProcessors (&NumberOfProcessors, &NumberOfEnabledProcessors);
+  Status = MpInitLibGetNumberOfProcessors (&NumberOfProcessors, &NumberOfEnabledProcessors);
+  ASSERT_EFI_ERROR (Status);
+
+  if (EFI_ERROR (Status)) {
+    NumberOfProcessors        = 1u;
+    NumberOfEnabledProcessors = 1u;
+  }
 
   BistInformationSize = sizeof (EFI_SEC_PLATFORM_INFORMATION_RECORD2) +
                         sizeof (EFI_SEC_PLATFORM_INFORMATION_CPU) * NumberOfProcessors;
diff --git a/UefiCpuPkg/CpuMpPei/CpuMpPei.c b/UefiCpuPkg/CpuMpPei/CpuMpPei.c
index e7f1fe9f426c..a84304273168 100644
--- a/UefiCpuPkg/CpuMpPei/CpuMpPei.c
+++ b/UefiCpuPkg/CpuMpPei/CpuMpPei.c
@@ -473,7 +473,13 @@ InitializeMpExceptionStackSwitchHandlers (
     return;
   }
 
-  MpInitLibGetNumberOfProcessors (&NumberOfProcessors, NULL);
+  Status = MpInitLibGetNumberOfProcessors (&NumberOfProcessors, NULL);
+  ASSERT_EFI_ERROR (Status);
+
+  if (EFI_ERROR (Status)) {
+    NumberOfProcessors = 1u;
+  }
+
   SwitchStackData = AllocatePages (EFI_SIZE_TO_PAGES (NumberOfProcessors * sizeof (EXCEPTION_STACK_SWITCH_CONTEXT)));
   ASSERT (SwitchStackData != NULL);
   ZeroMem (SwitchStackData, NumberOfProcessors * sizeof (EXCEPTION_STACK_SWITCH_CONTEXT));
diff --git a/UefiCpuPkg/CpuMpPei/CpuPaging.c b/UefiCpuPkg/CpuMpPei/CpuPaging.c
index 135422225340..1322fcb77f28 100644
--- a/UefiCpuPkg/CpuMpPei/CpuPaging.c
+++ b/UefiCpuPkg/CpuMpPei/CpuPaging.c
@@ -538,6 +538,7 @@ SetupStackGuardPage (
   UINTN                 NumberOfProcessors;
   UINTN                 Bsp;
   UINTN                 Index;
+  EFI_STATUS            Status;
 
   //
   // One extra page at the bottom of the stack is needed for Guard page.
@@ -547,7 +548,13 @@ SetupStackGuardPage (
     ASSERT (FALSE);
   }
 
-  MpInitLibGetNumberOfProcessors (&NumberOfProcessors, NULL);
+  Status = MpInitLibGetNumberOfProcessors (&NumberOfProcessors, NULL);
+  ASSERT_EFI_ERROR (Status);
+
+  if (EFI_ERROR (Status)) {
+    NumberOfProcessors = 1u;
+  }
+
   MpInitLibWhoAmI (&Bsp);
   for (Index = 0; Index < NumberOfProcessors; ++Index) {
     StackBase = 0;
-- 
2.39.2.windows.1