diff options
| author | Eric Dumazet <edumazet@google.com> | 2017-03-24 19:36:13 -0700 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2017-03-24 20:50:28 -0700 |
| commit | 43a6684519ab0a6c52024b5e25322476cabad893 (patch) | |
| tree | 5dd5811104b27efe5ac19bb1aabea5e137fbb276 | |
| parent | 13a8cd191a2b470cfd435b3b57dbd21aa65ff78c (diff) | |
| download | linux-43a6684519ab0a6c52024b5e25322476cabad893.tar.gz linux-43a6684519ab0a6c52024b5e25322476cabad893.tar.bz2 linux-43a6684519ab0a6c52024b5e25322476cabad893.zip | |
ping: implement proper locking
We got a report of yet another bug in ping
http://www.openwall.com/lists/oss-security/2017/03/24/6
->disconnect() is not called with socket lock held.
Fix this by acquiring ping rwlock earlier.
Thanks to Daniel, Alexander and Andrey for letting us know this problem.
Fixes: c319b4d76b9e ("net: ipv4: add IPPROTO_ICMP socket kind")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Daniel Jiang <danieljiang0415@gmail.com>
Reported-by: Solar Designer <solar@openwall.com>
Reported-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | net/ipv4/ping.c | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/net/ipv4/ping.c b/net/ipv4/ping.c index 2af6244b83e2..ccfbce13a633 100644 --- a/net/ipv4/ping.c +++ b/net/ipv4/ping.c @@ -156,17 +156,18 @@ int ping_hash(struct sock *sk) void ping_unhash(struct sock *sk) { struct inet_sock *isk = inet_sk(sk); + pr_debug("ping_unhash(isk=%p,isk->num=%u)\n", isk, isk->inet_num); + write_lock_bh(&ping_table.lock); if (sk_hashed(sk)) { - write_lock_bh(&ping_table.lock); hlist_nulls_del(&sk->sk_nulls_node); sk_nulls_node_init(&sk->sk_nulls_node); sock_put(sk); isk->inet_num = 0; isk->inet_sport = 0; sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1); - write_unlock_bh(&ping_table.lock); } + write_unlock_bh(&ping_table.lock); } EXPORT_SYMBOL_GPL(ping_unhash); |