tcp: Fix race in tcp_poll
authorTom Marshall <tdm.code@gmail.com>
Mon, 20 Sep 2010 22:42:05 +0000 (15:42 -0700)
committerDavid S. Miller <davem@davemloft.net>
Mon, 20 Sep 2010 22:42:05 +0000 (15:42 -0700)
commita4d258036ed9b2a1811c3670c6099203a0f284a0
tree58412022664aef745a99d254d20cf1a66aabda44
parent9828e6e6e3f19efcb476c567b9999891d051f52f
tcp: Fix race in tcp_poll

If a RST comes in immediately after checking sk->sk_err, tcp_poll will
return POLLIN but not POLLOUT.  Fix this by checking sk->sk_err at the end
of tcp_poll.  Additionally, ensure the correct order of operations on SMP
machines with memory barriers.

Signed-off-by: Tom Marshall <tdm.code@gmail.com>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
net/ipv4/tcp.c
net/ipv4/tcp_input.c