From: Sebastian Pop <s.pop@samsung.com>
Date: Wed, 15 Aug 2018 19:14:24 +0000 (-0500)
Subject: fix bug #184: clear out buf to avoid msan use-of-uninitialized-value
X-Git-Tag: 1.9.9-b1~621
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=baddc82378c6fa0d1c18651522fc1cc2662e5c50;p=thirdparty%2Fzlib-ng.git

fix bug #184: clear out buf to avoid msan use-of-uninitialized-value

Do not use bzero as suggested by Mika Lindqvist:
> You shouldn't use bzero() in new code as some compilers, like Visual C++,
> don't have it... New code should just use memset().
---

diff --git a/test/minigzip.c b/test/minigzip.c
index dc06c35ac..7868c64dd 100644
--- a/test/minigzip.c
+++ b/test/minigzip.c
@@ -291,6 +291,9 @@ void gz_compress(FILE   *in, gzFile out)
      */
     if (gz_compress_mmap(in, out) == Z_OK) return;
 #endif
+    /* Clear out the contents of buf before reading from the file to avoid
+       MemorySanitizer: use-of-uninitialized-value warnings. */
+    memset(buf, 0, sizeof(buf));
     for (;;) {
         len = (int)fread(buf, 1, sizeof(buf), in);
         if (ferror(in)) {