From: Eric Dumazet Date: Tue, 11 Jan 2011 01:14:22 +0000 (+0000) Subject: tcp: disallow bind() to reuse addr/port X-Git-Tag: v2.6.38-rc1~403^2~8 X-Git-Url: https://openfabrics.org/gitweb/?a=commitdiff_plain;h=c191a836a908d1dd6b40c503741f91b914de3348;p=~emulex%2Finfiniband.git tcp: disallow bind() to reuse addr/port inet_csk_bind_conflict() logic currently disallows a bind() if it finds a friend socket (a socket bound on same address/port) satisfying a set of conditions : 1) Current (to be bound) socket doesnt have sk_reuse set OR 2) other socket doesnt have sk_reuse set OR 3) other socket is in LISTEN state We should add the CLOSE state in the 3) condition, in order to avoid two REUSEADDR sockets in CLOSE state with same local address/port, since this can deny further operations. Note : a prior patch tried to address the problem in a different (and buggy) way. (commit fda48a0d7a8412ced tcp: bind() fix when many ports are bound). Reported-by: Gaspar Chilingarov Reported-by: Daniel Baluta Tested-by: Daniel Baluta Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller --- diff --git a/net/ipv4/inet_connection_sock.c b/net/ipv4/inet_connection_sock.c index 25e318153f1..97e5fb76526 100644 --- a/net/ipv4/inet_connection_sock.c +++ b/net/ipv4/inet_connection_sock.c @@ -73,7 +73,7 @@ int inet_csk_bind_conflict(const struct sock *sk, !sk2->sk_bound_dev_if || sk->sk_bound_dev_if == sk2->sk_bound_dev_if)) { if (!reuse || !sk2->sk_reuse || - sk2->sk_state == TCP_LISTEN) { + ((1 << sk2->sk_state) & (TCPF_LISTEN | TCPF_CLOSE))) { const __be32 sk2_rcv_saddr = sk_rcv_saddr(sk2); if (!sk2_rcv_saddr || !sk_rcv_saddr(sk) || sk2_rcv_saddr == sk_rcv_saddr(sk)) @@ -122,7 +122,8 @@ again: (tb->num_owners < smallest_size || smallest_size == -1)) { smallest_size = tb->num_owners; smallest_rover = rover; - if (atomic_read(&hashinfo->bsockets) > (high - low) + 1) { + if (atomic_read(&hashinfo->bsockets) > (high - low) + 1 && + !inet_csk(sk)->icsk_af_ops->bind_conflict(sk, tb)) { spin_unlock(&head->lock); snum = smallest_rover; goto have_snum; diff --git a/net/ipv6/inet6_connection_sock.c b/net/ipv6/inet6_connection_sock.c index e46305d1815..d144e629d2b 100644 --- a/net/ipv6/inet6_connection_sock.c +++ b/net/ipv6/inet6_connection_sock.c @@ -44,7 +44,7 @@ int inet6_csk_bind_conflict(const struct sock *sk, !sk2->sk_bound_dev_if || sk->sk_bound_dev_if == sk2->sk_bound_dev_if) && (!sk->sk_reuse || !sk2->sk_reuse || - sk2->sk_state == TCP_LISTEN) && + ((1 << sk2->sk_state) & (TCPF_LISTEN | TCPF_CLOSE))) && ipv6_rcv_saddr_equal(sk, sk2)) break; }