From: Phil Sutter <psutter@redhat.com>
Date: Fri, 12 Aug 2016 12:39:50 +0000 (+0200)
Subject: utils: Don't return directly from SNPRINTF_BUFFER_SIZE
X-Git-Tag: libnftnl-1.0.7~51
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=9afae310b019aa497afb94833afc9a936bc38a1f;p=thirdparty%2Flibnftnl.git

utils: Don't return directly from SNPRINTF_BUFFER_SIZE

Apart from being a bad idea in general, the return statement contained
in that macro in some cases leads to returning from functions without
properly cleaning up, thereby causing memory leaks.

Instead, just sanitize the value in 'ret' to not harm further calls of
snprintf() (as 'len' will eventually just become zero).

Cc: Arturo Borrero <arturo.borrero.glez@gmail.com>
Signed-off-by: Phil Sutter <phil@nwl.cc>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---

diff --git a/include/utils.h b/include/utils.h
index 21694b6a..924df324 100644
--- a/include/utils.h
+++ b/include/utils.h
@@ -54,7 +54,7 @@ void __nftnl_assert_attr_exists(uint16_t attr, uint16_t attr_max,
 
 #define SNPRINTF_BUFFER_SIZE(ret, size, len, offset)	\
 	if (ret < 0)					\
-		return ret;				\
+		ret = 0;				\
 	offset += ret;					\
 	if (ret > len)					\
 		ret = len;				\