libmicrohttpd

commit 78a903946d707cab78c5eb996312deccb3f68c82
parent 866b60aeb94a0fbb751d69802ed16ed09414aa34
Author: Evgeny Grin (Karlson2k) <k2k@narod.ru>
Date:   Fri, 19 Apr 2019 10:35:35 +0300

sha256_update(): added shortcut for empty data,
avoid wrong/undefined behaviour of memcpy() with null pointer

Diffstat:
M
src/microhttpd/sha256.c
 | 
3
+++

1 file changed, 3 insertions(+), 0 deletions(-)
diff --git a/src/microhttpd/sha256.c b/src/microhttpd/sha256.c
@@ -250,6 +250,9 @@ sha256_update (void *ctx_,
 
   mhd_assert((data != NULL) || (length == 0));
 
+  if (0 == length)
+    return; /* Do nothing */
+
   /* Note: (count & (SHA256_BLOCK_SIZE-1))
            equal (count % SHA256_BLOCK_SIZE) for this block size. */
   bytes_have = (unsigned)(ctx->count & (SHA256_BLOCK_SIZE-1));