SecurityPkg: Guard nullable return values

Makes changes to comply with CodeQL unguarded-null-return-dereference
alerts.

Signed-off-by: Oliver Smith-Denny <osde@microsoft.com>

2 files changed, 26 insertions, 6 deletions

diff --git a/SecurityPkg/VariableAuthenticated/SecureBootConfigDxe/SecureBootConfigFileExplorer.c b/SecurityPkg/VariableAuthenticated/SecureBootConfigDxe/SecureBootConfigFileExplorer.c
index 5a23dc517a..65b3f81b6e 100644
--- a/SecurityPkg/VariableAuthenticated/SecureBootConfigDxe/SecureBootConfigFileExplorer.c
+++ b/SecurityPkg/VariableAuthenticated/SecureBootConfigDxe/SecureBootConfigFileExplorer.c
@@ -98,7 +98,11 @@ ExtractFileNameFromDevicePath (
 

   ASSERT (DevicePath != NULL);

 

-  String      = DevicePathToStr (DevicePath);

+  String = DevicePathToStr (DevicePath);

+  if (String == NULL) {

+    return NULL;

+  }

+

   MatchString = String;

   LastMatch   = String;

   FileName    = NULL;

diff --git a/SecurityPkg/VariableAuthenticated/SecureBootConfigDxe/SecureBootConfigImpl.c b/SecurityPkg/VariableAuthenticated/SecureBootConfigDxe/SecureBootConfigImpl.c
index 1b3b51eea7..95a59c41de 100644
--- a/SecurityPkg/VariableAuthenticated/SecureBootConfigDxe/SecureBootConfigImpl.c
+++ b/SecurityPkg/VariableAuthenticated/SecureBootConfigDxe/SecureBootConfigImpl.c
@@ -1172,7 +1172,10 @@ CalculateCertHash (
   //

   CtxSize = mHash[HashAlg].GetContextSize ();

   HashCtx = AllocatePool (CtxSize);

-  ASSERT (HashCtx != NULL);

+  if (HashCtx == NULL) {

+    ASSERT (HashCtx != NULL);

+    return FALSE;

+  }

 

   //

   // 2. Initialize a hash context.

@@ -1886,7 +1889,10 @@ HashPeImage (
   CtxSize = mHash[HashAlg].GetContextSize ();

 

   HashCtx = AllocatePool (CtxSize);

-  ASSERT (HashCtx != NULL);

+  if (HashCtx == NULL) {

+    ASSERT (HashCtx != NULL);

+    goto Done;

+  }

 

   // 1.  Load the image header into memory.

 

@@ -3511,9 +3517,19 @@ SecureBootExtractConfig (
     // followed by "&OFFSET=0&WIDTH=WWWWWWWWWWWWWWWW" followed by a Null-terminator

     //

     ConfigRequestHdr = HiiConstructConfigHdr (&gSecureBootConfigFormSetGuid, mSecureBootStorageName, PrivateData->DriverHandle);

-    Size             = (StrLen (ConfigRequestHdr) + 32 + 1) * sizeof (CHAR16);

-    ConfigRequest    = AllocateZeroPool (Size);

-    ASSERT (ConfigRequest != NULL);

+    if (ConfigRequestHdr == NULL) {

+      ASSERT (ConfigRequestHdr != NULL);

+      return EFI_OUT_OF_RESOURCES;

+    }

+

+    Size          = (StrLen (ConfigRequestHdr) + 32 + 1) * sizeof (CHAR16);

+    ConfigRequest = AllocateZeroPool (Size);

+    if (ConfigRequest == NULL) {

+      ASSERT (ConfigRequest != NULL);

+      FreePool (ConfigRequestHdr);

+      return EFI_OUT_OF_RESOURCES;

+    }

+

     AllocatedRequest = TRUE;

     UnicodeSPrint (ConfigRequest, Size, L"%s&OFFSET=0&WIDTH=%016LX", ConfigRequestHdr, (UINT64)BufferSize);

     FreePool (ConfigRequestHdr);