New patch to review for coreboot: 56d96b4 amd/pi/00730F01/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/8208

-gerrit

commit 56d96b491ad559c42721a9eba4c595bf91f505b7
Author: Edward O'Callaghan 
Date:   Wed Jan 14 02:22:01 2015 +1100

amd/pi/00730F01/Lib/amdlib.c: Integer overflow in loop construct

Forward port fix in: commit 'cb0dd58 Integer overflow in loop construct'.

Change-Id: Id03900d9132477b5dd90cedd8af3a265e6f9165a
    Signed-off-by: Edward O'Callaghan 
---
 src/vendorcode/amd/pi/00730F01/Lib/amdlib.c | 16 +++++++++++-----
 1 file changed, 11 insertions(+), 5 deletions(-)

diff --git a/src/vendorcode/amd/pi/00730F01/Lib/amdlib.c b/src/vendorcode/amd/pi/00730F01/Lib/amdlib.c
index 5e85f6b..369daea 100644
--- a/src/vendorcode/amd/pi/00730F01/Lib/amdlib.c
+++ b/src/vendorcode/amd/pi/00730F01/Lib/amdlib.c
@@ -381,11 +381,17 @@ LibAmdBitScanReverse (
   IN       UINT32 value
 )
 {
-  UINTN Index;
-  for (Index = 31; Index >= 0; Index--){
-      if (value & (1 << Index)) break;
-  }
-  return (UINT8) Index;
+  uint8_t bit = 31;
+  do {
+    if (value & (1 << 31))
+      return bit;
+
+    value <<= 1;
+    bit--;
+
+  } while (value != 0);
+
+  return 0xFF; /* Error code indicating no bit found */
 }

AMDLIB_OPTIMIZE