MdeModulePkg: Variable cumulative codeql issues.

Running Codeql on MdeModulePkg/Universal/Variable drivers results
in codeql errors stemming for the following two checks.

- cpp/comparison-with-wider-type
- cpp/overflow-buffer
- cpp/missing-null-test

Signed-off-by: Aaron Pop <aaronpop@microsoft.com>

Co-authored-by: Michael Kubacki <michael.kubacki@microsoft.com>
Co-authored-by: Taylor Beebe <tabeebe@microsoft.com>
Co-authored-by: pohanch <125842322+pohanch@users.noreply.github.com>
Co-authored-by: kenlautner <85201046+kenlautner@users.noreply.github.com>
Co-authored-by: Oliver Smith-Denny <osde@linux.microsoft.com>
Co-authored-by: Sean Brogan <sean.brogan@microsoft.com>
Co-authored-by: Aaron <aaronpop@microsoft>

3 files changed, 72 insertions, 65 deletions

diff --git a/MdeModulePkg/Universal/Variable/Pei/Variable.c b/MdeModulePkg/Universal/Variable/Pei/Variable.c
index 9f3d434..8bd72f0 100644
--- a/MdeModulePkg/Universal/Variable/Pei/Variable.c
+++ b/MdeModulePkg/Universal/Variable/Pei/Variable.c
@@ -913,7 +913,7 @@ FindVariableEx (
     }

   }

 

-  if (MaxIndex != NULL) {

+  if ((MaxIndex != NULL) && (VariableHeader != NULL)) {

     //

     // HOB exists but the variable cannot be found in HOB

     // If not found in HOB, then let's start from the MaxIndex we've found.

@@ -1164,7 +1164,7 @@ PeiGetNextVariableName (
   VariableHeader = NULL;

 

   Status = FindVariable (VariableName, VariableGuid, &Variable, &StoreInfo);

-  if ((Variable.CurrPtr == NULL) || (Status != EFI_SUCCESS)) {

+  if ((Status != EFI_SUCCESS) || (Variable.CurrPtr == NULL)) {

     return Status;

   }

 

diff --git a/MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.c b/MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.c
index 1c76590..10fb4a3 100644
--- a/MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.c
+++ b/MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.c
@@ -1549,39 +1549,40 @@ AutoUpdateLangVariable (
         // Get the corresponding ISO639 language tag according to RFC4646 language tag.

         //

         BestLang = GetLangFromSupportedLangCodes (mVariableModuleGlobal->LangCodes, Index, TRUE);

-

-        //

-        // Check the variable space for both Lang and PlatformLang variable.

-        //

-        VariableEntry[0].VariableSize = ISO_639_2_ENTRY_SIZE + 1;

-        VariableEntry[0].Guid         = &gEfiGlobalVariableGuid;

-        VariableEntry[0].Name         = EFI_LANG_VARIABLE_NAME;

-

-        VariableEntry[1].VariableSize = AsciiStrSize (BestPlatformLang);

-        VariableEntry[1].Guid         = &gEfiGlobalVariableGuid;

-        VariableEntry[1].Name         = EFI_PLATFORM_LANG_VARIABLE_NAME;

-        if (!CheckRemainingSpaceForConsistency (VARIABLE_ATTRIBUTE_NV_BS_RT, &VariableEntry[0], &VariableEntry[1], NULL)) {

-          //

-          // No enough variable space to set both Lang and PlatformLang successfully.

-          //

-          Status = EFI_OUT_OF_RESOURCES;

-        } else {

+        if (BestLang != NULL) {

           //

-          // Successfully convert PlatformLang to Lang, and set the BestLang value into Lang variable simultaneously.

+          // Check the variable space for both Lang and PlatformLang variable.

           //

-          FindVariable (EFI_LANG_VARIABLE_NAME, &gEfiGlobalVariableGuid, &Variable, &mVariableModuleGlobal->VariableGlobal, FALSE);

-

-          Status = UpdateVariable (

-                     EFI_LANG_VARIABLE_NAME,

-                     &gEfiGlobalVariableGuid,

-                     BestLang,

-                     ISO_639_2_ENTRY_SIZE + 1,

-                     Attributes,

-                     0,

-                     0,

-                     &Variable,

-                     NULL

-                     );

+          VariableEntry[0].VariableSize = ISO_639_2_ENTRY_SIZE + 1;

+          VariableEntry[0].Guid         = &gEfiGlobalVariableGuid;

+          VariableEntry[0].Name         = EFI_LANG_VARIABLE_NAME;

+

+          VariableEntry[1].VariableSize = AsciiStrSize (BestPlatformLang);

+          VariableEntry[1].Guid         = &gEfiGlobalVariableGuid;

+          VariableEntry[1].Name         = EFI_PLATFORM_LANG_VARIABLE_NAME;

+          if (!CheckRemainingSpaceForConsistency (VARIABLE_ATTRIBUTE_NV_BS_RT, &VariableEntry[0], &VariableEntry[1], NULL)) {

+            //

+            // No enough variable space to set both Lang and PlatformLang successfully.

+            //

+            Status = EFI_OUT_OF_RESOURCES;

+          } else {

+            //

+            // Successfully convert PlatformLang to Lang, and set the BestLang value into Lang variable simultaneously.

+            //

+            FindVariable (EFI_LANG_VARIABLE_NAME, &gEfiGlobalVariableGuid, &Variable, &mVariableModuleGlobal->VariableGlobal, FALSE);

+

+            Status = UpdateVariable (

+                       EFI_LANG_VARIABLE_NAME,

+                       &gEfiGlobalVariableGuid,

+                       BestLang,

+                       ISO_639_2_ENTRY_SIZE + 1,

+                       Attributes,

+                       0,

+                       0,

+                       &Variable,

+                       NULL

+                       );

+          }

         }

 

         DEBUG ((DEBUG_INFO, "Variable Driver Auto Update PlatformLang, PlatformLang:%a, Lang:%a Status: %r\n", BestPlatformLang, BestLang, Status));

@@ -1606,39 +1607,40 @@ AutoUpdateLangVariable (
         // Get the corresponding RFC4646 language tag according to ISO639 language tag.

         //

         BestPlatformLang = GetLangFromSupportedLangCodes (mVariableModuleGlobal->PlatformLangCodes, Index, FALSE);

-

-        //

-        // Check the variable space for both PlatformLang and Lang variable.

-        //

-        VariableEntry[0].VariableSize = AsciiStrSize (BestPlatformLang);

-        VariableEntry[0].Guid         = &gEfiGlobalVariableGuid;

-        VariableEntry[0].Name         = EFI_PLATFORM_LANG_VARIABLE_NAME;

-

-        VariableEntry[1].VariableSize = ISO_639_2_ENTRY_SIZE + 1;

-        VariableEntry[1].Guid         = &gEfiGlobalVariableGuid;

-        VariableEntry[1].Name         = EFI_LANG_VARIABLE_NAME;

-        if (!CheckRemainingSpaceForConsistency (VARIABLE_ATTRIBUTE_NV_BS_RT, &VariableEntry[0], &VariableEntry[1], NULL)) {

-          //

-          // No enough variable space to set both PlatformLang and Lang successfully.

-          //

-          Status = EFI_OUT_OF_RESOURCES;

-        } else {

+        if (BestPlatformLang != NULL) {

           //

-          // Successfully convert Lang to PlatformLang, and set the BestPlatformLang value into PlatformLang variable simultaneously.

+          // Check the variable space for both PlatformLang and Lang variable.

           //

-          FindVariable (EFI_PLATFORM_LANG_VARIABLE_NAME, &gEfiGlobalVariableGuid, &Variable, &mVariableModuleGlobal->VariableGlobal, FALSE);

-

-          Status = UpdateVariable (

-                     EFI_PLATFORM_LANG_VARIABLE_NAME,

-                     &gEfiGlobalVariableGuid,

-                     BestPlatformLang,

-                     AsciiStrSize (BestPlatformLang),

-                     Attributes,

-                     0,

-                     0,

-                     &Variable,

-                     NULL

-                     );

+          VariableEntry[0].VariableSize = AsciiStrSize (BestPlatformLang);

+          VariableEntry[0].Guid         = &gEfiGlobalVariableGuid;

+          VariableEntry[0].Name         = EFI_PLATFORM_LANG_VARIABLE_NAME;

+

+          VariableEntry[1].VariableSize = ISO_639_2_ENTRY_SIZE + 1;

+          VariableEntry[1].Guid         = &gEfiGlobalVariableGuid;

+          VariableEntry[1].Name         = EFI_LANG_VARIABLE_NAME;

+          if (!CheckRemainingSpaceForConsistency (VARIABLE_ATTRIBUTE_NV_BS_RT, &VariableEntry[0], &VariableEntry[1], NULL)) {

+            //

+            // No enough variable space to set both PlatformLang and Lang successfully.

+            //

+            Status = EFI_OUT_OF_RESOURCES;

+          } else {

+            //

+            // Successfully convert Lang to PlatformLang, and set the BestPlatformLang value into PlatformLang variable simultaneously.

+            //

+            FindVariable (EFI_PLATFORM_LANG_VARIABLE_NAME, &gEfiGlobalVariableGuid, &Variable, &mVariableModuleGlobal->VariableGlobal, FALSE);

+

+            Status = UpdateVariable (

+                       EFI_PLATFORM_LANG_VARIABLE_NAME,

+                       &gEfiGlobalVariableGuid,

+                       BestPlatformLang,

+                       AsciiStrSize (BestPlatformLang),

+                       Attributes,

+                       0,

+                       0,

+                       &Variable,

+                       NULL

+                       );

+          }

         }

 

         DEBUG ((DEBUG_INFO, "Variable Driver Auto Update Lang, Lang:%a, PlatformLang:%a Status: %r\n", BestLang, BestPlatformLang, Status));

diff --git a/MdeModulePkg/Universal/Variable/RuntimeDxe/VariablePolicySmmDxe.c b/MdeModulePkg/Universal/Variable/RuntimeDxe/VariablePolicySmmDxe.c
index 984cae1..60d16e9 100644
--- a/MdeModulePkg/Universal/Variable/RuntimeDxe/VariablePolicySmmDxe.c
+++ b/MdeModulePkg/Universal/Variable/RuntimeDxe/VariablePolicySmmDxe.c
@@ -477,6 +477,8 @@ InternalProtocolGetVariablePolicyInfo (
   UINTN                                  BufferSize;

   UINTN                                  VariableNameSize;

 

+  PolicyHeader = NULL;

+

   if ((VariableName == NULL) || (VendorGuid == NULL) || (VariablePolicy == NULL)) {

     return EFI_INVALID_PARAMETER;

   }

@@ -609,8 +611,11 @@ InternalProtocolGetVariablePolicyInfo (
 

 Done:

   ReleaseLockOnlyAtBootTime (&mMmCommunicationLock);

+  if (EFI_ERROR (Status)) {

+    return Status;

+  }

 

-  return (EFI_ERROR (Status)) ? Status : PolicyHeader->Result;

+  return (PolicyHeader != NULL) ? PolicyHeader->Result : EFI_SUCCESS;

 }

 

 /**