ipv4: avoid passing NULL to inet_putpeer() in icmpv4_xrlim_allow()

inet_getpeer_v4() can return NULL under OOM conditions, and while
inet_peer_xrlim_allow() is OK with a NULL peer, inet_putpeer() will
crash.

This code path now uses the same idiom as the others from:
1d861aa4b3fb08822055345f480850205ffe6170 ("inet: Minimize use of
cached route inetpeer.").

Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/ipv4/icmp.c b/net/ipv4/icmp.c
index f2eccd5..17ff9fd 100644 (file)
--- a/net/ipv4/icmp.c
+++ b/net/ipv4/icmp.c
@@ -257,7 +257,8 @@ static inline bool icmpv4_xrlim_allow(struct net *net, struct rtable *rt,
                struct inet_peer *peer = inet_getpeer_v4(net->ipv4.peers, fl4->daddr, 1);
                rc = inet_peer_xrlim_allow(peer,
                                           net->ipv4.sysctl_icmp_ratelimit);
-               inet_putpeer(peer);
+               if (peer)
+                       inet_putpeer(peer);
        }
 out:
        return rc;