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>

1 files changed, 2 insertions, 1 deletions

diff --git a/net/ipv4/icmp.c b/net/ipv4/icmp.c
index f2eccd531746..17ff9fd7cdda 100644
--- 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;