[iptables PATCH] xshared: fix memory leak in should_load_proto

[Christian Marangi <ansuelsmth@gmail.com>]

With the help of a Coverity Scan, it was pointed out that it's present a
memory leak in the corner case where find_proto is not NULL in the
function should_load_proto. find_proto return a struct xtables_match
pointer from xtables_find_match that is allocated but never freed.

Correctly free the found proto in the corner case where find_proto
succeed.

Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>
---
 iptables/xshared.c | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/iptables/xshared.c b/iptables/xshared.c
index 17aed04e..0beacfdc 100644
--- a/iptables/xshared.c
+++ b/iptables/xshared.c
@@ -113,11 +113,16 @@ find_proto(const char *pname, enum xtables_tryload tryload,
  */
 static bool should_load_proto(struct iptables_command_state *cs)
 {
+	struct xtables_match *proto;
+
 	if (cs->protocol == NULL)
 		return false;
-	if (find_proto(cs->protocol, XTF_DONT_LOAD,
-	    cs->options & OPT_NUMERIC, NULL) == NULL)
+	proto = find_proto(cs->protocol, XTF_DONT_LOAD,
+			   cs->options & OPT_NUMERIC, NULL);
+	if (proto == NULL)
 		return true;
+
+	free(proto);
 	return !cs->proto_used;
 }
 
-- 
2.39.2