Fix potential NULL ptr crash if compiled with DMALLOC

In the unlikely case that we are compiled with -DDMALLOC *and*
malloc() returns NULL, there is an uncaught memset() which would
crash then.  Remove the memset(), as the right the next operation
after check_malloc_return() is a mempcy() which will overwrite
the whole memory block anyway.

Trac: #586

Signed-off-by: Gert Doering <gert@greenie.muc.de>
Acked-by: Antonio Quartulli <antonio@openvpn.net>
Message-Id: <20210402173414.14216-1-gert@greenie.muc.de>
URL: https://www.mail-archive.com/openvpn-devel@lists.sourceforge.net/msg21981.html
Signed-off-by: Gert Doering <gert@greenie.muc.de>

diff --git a/src/openvpn/buffer.c b/src/openvpn/buffer.c
index 48bf25d53da7c18c049ebd40dbdc6d4e309a56c0..e7031a4fdd975ff7d0f9c157391e3b2ee12ef5eb 100644 (file)
--- a/src/openvpn/buffer.c
+++ b/src/openvpn/buffer.c
@@ -706,7 +706,6 @@ string_alloc(const char *str, struct gc_arena *gc)
              */
 #ifdef DMALLOC
             ret = openvpn_dmalloc(file, line, n);
-            memset(ret, 0, n);
 #else
             ret = calloc(1, n);
 #endif