ip: fix error handling in ip_finish_output2()

__neigh_create() returns either a pointer to struct neighbour or PTR_ERR(). But the caller expects it to return either a pointer or NULL. Replace the NULL check with IS_ERR() check. The bug was introduced in a263b30 ("ipv4: Make neigh lookups directly in output packet path."). Signed-off-by: Vasily Kulikov <[email protected]> Signed-off-by: David S. Miller <[email protected]>
mna · Aug 6, 2012 · 9871f1a · 9871f1a
1 parent 91d27a8
commit 9871f1a
Showing 1 changed file with 1 addition and 1 deletion.
diff --git a/net/ipv4/ip_output.c b/net/ipv4/ip_output.c
@@ -197,7 +197,7 @@ static inline int ip_finish_output2(struct sk_buff *skb)
 	neigh = __ipv4_neigh_lookup_noref(dev, nexthop);
 	if (unlikely(!neigh))
 		neigh = __neigh_create(&arp_tbl, &nexthop, dev, false);
-	if (neigh) {
+	if (!IS_ERR(neigh)) {
 		int res = dst_neigh_output(dst, neigh, skb);
 
 		rcu_read_unlock_bh();