[CRYPTO] scatterwalk: Handle zero nbytes in scatterwalk_map_and_copy

It's better to return silently than crash and burn when someone feeds us a zero length. In particular the null digest algorithm when used as part of authenc will do that to us. Signed-off-by: Herbert Xu <[email protected]>
RyanHsu · Jan 10, 2008 · 6e05077 · 6e05077
1 parent ce5bd4a
commit 6e05077
Showing 1 changed file with 3 additions and 0 deletions.
diff --git a/crypto/scatterwalk.c b/crypto/scatterwalk.c
@@ -105,6 +105,9 @@ void scatterwalk_map_and_copy(void *buf, struct scatterlist *sg,
 	struct scatter_walk walk;
 	unsigned int offset = 0;
 
+	if (!nbytes)
+		return;
+
 	for (;;) {
 		scatterwalk_start(&walk, sg);