netfilter: Fix potential use after free in ip6_route_me_harder()

Dst is released one line before we access it again with dst->error.

Fixes: 58e35d1471 netfilter: ipv6: propagate routing errors from
ip6_route_me_harder()

Signed-off-by: Sergey Popovich <popovich_sergei@mail.ru>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This commit is contained in:
Sergey Popovich 2014-05-08 16:22:35 +03:00 committed by Pablo Neira Ayuso
parent aff09ce303
commit a8951d5814

View File

@ -30,13 +30,15 @@ int ip6_route_me_harder(struct sk_buff *skb)
.daddr = iph->daddr,
.saddr = iph->saddr,
};
int err;
dst = ip6_route_output(net, skb->sk, &fl6);
if (dst->error) {
err = dst->error;
if (err) {
IP6_INC_STATS(net, ip6_dst_idev(dst), IPSTATS_MIB_OUTNOROUTES);
LIMIT_NETDEBUG(KERN_DEBUG "ip6_route_me_harder: No more route.\n");
dst_release(dst);
return dst->error;
return err;
}
/* Drop old route. */