New patch to review for coreboot: 4618ad3 amd/agesa/f16kb/Lib/amdlib.c: Integer overflow in loop construct

[Edward O'Callaghan]

Edward O'Callaghan ([e-mail]) just uploaded a new patch set to gerrit, which you can find at http://review.coreboot.org/7676

-gerrit

commit 4618ad3de79e33c34c7c625a1d941c1f6f9caea9
Author: Edward O'Callaghan 
Date:   Sun Dec 7 05:20:14 2014 +1100

amd/agesa/f16kb/Lib/amdlib.c: Integer overflow in loop construct

As is the case in commit:

3312ed7 amd/agesa/f1?/Lib/amdlib.c: Integer overflow in loop construct

The semantics of this loop relies on an integer overflow in Index >=0
    that implies a return value of (UINT8)-1 which around wraps to 0xFF, or
    VOLT_UNSUPPORTED.

Change-Id: Iced3eff3ae7b8935db3bdd6147372cf3b540883c
    Signed-off-by: Edward O'Callaghan 
---
 src/vendorcode/amd/agesa/f16kb/Lib/amdlib.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/src/vendorcode/amd/agesa/f16kb/Lib/amdlib.c b/src/vendorcode/amd/agesa/f16kb/Lib/amdlib.c
index d0e66b9..3a7ada8 100644
--- a/src/vendorcode/amd/agesa/f16kb/Lib/amdlib.c
+++ b/src/vendorcode/amd/agesa/f16kb/Lib/amdlib.c
@@ -360,11 +360,11 @@ LibAmdBitScanReverse (
   IN       UINT32 value
 )
 {
-  UINTN Index;
+  UINT8 Index;
   for (Index = 31; Index >= 0; Index--){
-      if (value & (1 << Index)) break;
+      if (value & (1 << Index)) return Index;
   }
-  return (UINT8) Index;
+  return 0xFF;
 }
 VOID
 LibAmdMsrRead (