Fix a bug in variable driver cache mechanism:

It should return EFI_SUCCESS and update the output buffer size if the input buffer is larger than actual variable contents.

git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@4182 6f19259b-4bc3-4df7-8a09-765794883524

1 files changed, 2 insertions, 1 deletions

diff --git a/MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.c b/MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.c
index 34bc4a8..20eeebe 100644
--- a/MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.c
+++ b/MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.c
@@ -676,11 +676,12 @@ FindVariableInCache (
         if (Entry->DataSize == 0) {

           // Variable was deleted so return not found

           return EFI_NOT_FOUND;

-        } else if (Entry->DataSize != *DataSize) {

+        } else if (Entry->DataSize > *DataSize) {

           // If the buffer is too small return correct size

           *DataSize = Entry->DataSize;

           return EFI_BUFFER_TOO_SMALL;

         } else {

+          *DataSize = Entry->DataSize;

           // Return the data

           CopyMem (Data, Entry->Data, Entry->DataSize);

           if (Attributes != NULL) {