diff options
| -rw-r--r-- | MdePkg/Library/UefiDevicePathLibDevicePathProtocol/UefiDevicePathLib.c | 26 |
1 files changed, 21 insertions, 5 deletions
diff --git a/MdePkg/Library/UefiDevicePathLibDevicePathProtocol/UefiDevicePathLib.c b/MdePkg/Library/UefiDevicePathLibDevicePathProtocol/UefiDevicePathLib.c index a514f1b6f9..2252d186cb 100644 --- a/MdePkg/Library/UefiDevicePathLibDevicePathProtocol/UefiDevicePathLib.c +++ b/MdePkg/Library/UefiDevicePathLibDevicePathProtocol/UefiDevicePathLib.c @@ -103,17 +103,33 @@ IsDevicePathValid ( ASSERT (DevicePath != NULL);
+ if (MaxSize == 0) {
+ MaxSize = MAX_UINTN;
+ }
+
+ //
+ // Validate the input size big enough to touch the first node.
+ //
+ if (MaxSize < sizeof (EFI_DEVICE_PATH_PROTOCOL)) {
+ return FALSE;
+ }
+
for (Count = 0, Size = 0; !IsDevicePathEnd (DevicePath); DevicePath = NextDevicePathNode (DevicePath)) {
NodeLength = DevicePathNodeLength (DevicePath);
if (NodeLength < sizeof (EFI_DEVICE_PATH_PROTOCOL)) {
return FALSE;
}
- if (MaxSize > 0) {
- Size += NodeLength;
- if (Size + END_DEVICE_PATH_LENGTH > MaxSize) {
- return FALSE;
- }
+ if (NodeLength > MAX_UINTN - Size) {
+ return FALSE;
+ }
+ Size += NodeLength;
+
+ //
+ // Validate next node before touch it.
+ //
+ if (Size > MaxSize - END_DEVICE_PATH_LENGTH ) {
+ return FALSE;
}
if (PcdGet32 (PcdMaximumDevicePathNodeCount) > 0) {
|