netfilter: bridge: don't leak skb in error paths

br_nf_dev_queue_xmit must free skb in its error path.
NF_DROP is misleading -- its an okfn, not a netfilter hook.

Fixes: 70ab905bdb5fb ("bridge : Sanitize skb before it enters the IP stack")
Fixes: 46d1316b8c027 ("netfilter: bridge: forward IPv6 fragmented packets")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

diff --git a/net/bridge/br_netfilter_hooks.c b/net/bridge/br_netfilter_hooks.c
index 8a394bd3af83b6a67362d054bb39adb7c02d902e..c8b9bcfe997e48556cfc2633981e272e063f6880 100644 (file)
--- a/net/bridge/br_netfilter_hooks.c
+++ b/net/bridge/br_netfilter_hooks.c
@@ -744,7 +744,7 @@ static int br_nf_dev_queue_xmit(struct sock *sk, struct sk_buff *skb)
                struct brnf_frag_data *data;
 
                if (br_validate_ipv4(skb))
-                       return NF_DROP;
+                       goto drop;
 
                IPCB(skb)->frag_max_size = nf_bridge->frag_max_size;
 
@@ -769,7 +769,7 @@ static int br_nf_dev_queue_xmit(struct sock *sk, struct sk_buff *skb)
                struct brnf_frag_data *data;
 
                if (br_validate_ipv6(skb))
-                       return NF_DROP;
+                       goto drop;
 
                IP6CB(skb)->frag_max_size = nf_bridge->frag_max_size;
 
@@ -784,12 +784,16 @@ static int br_nf_dev_queue_xmit(struct sock *sk, struct sk_buff *skb)
 
                if (v6ops)
                        return v6ops->fragment(sk, skb, br_nf_push_frag_xmit);
-               else
-                       return -EMSGSIZE;
+
+               kfree_skb(skb);
+               return -EMSGSIZE;
        }
 #endif
        nf_bridge_info_free(skb);
        return br_dev_queue_push_xmit(sk, skb);
+ drop:
+       kfree_skb(skb);
+       return 0;
 }
 
 /* PF_BRIDGE/POST_ROUTING ********************************************/