4.20-stable review patch. If anyone has any objections, please let me know.
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From: Willem de Bruijn willemb@google.com
[ Upstream commit 13d7f46386e060df31b727c9975e38306fa51e7a ]
TCP transmission with MSG_ZEROCOPY fails if the peer closes its end of the connection and so transitions this socket to CLOSE_WAIT state.
Transmission in close wait state is acceptable. Other similar tests in the stack (e.g., in FastOpen) accept both states. Relax this test, too.
Link: https://www.mail-archive.com/netdev@vger.kernel.org/msg276886.html Link: https://www.mail-archive.com/netdev@vger.kernel.org/msg227390.html Fixes: f214f915e7db ("tcp: enable MSG_ZEROCOPY") Reported-by: Marek Majkowski marek@cloudflare.com Signed-off-by: Willem de Bruijn willemb@google.com CC: Yuchung Cheng ycheng@google.com CC: Neal Cardwell ncardwell@google.com CC: Soheil Hassas Yeganeh soheil@google.com CC: Alexey Kodanev alexey.kodanev@oracle.com Acked-by: Soheil Hassas Yeganeh soheil@google.com Reviewed-by: Eric Dumazet edumazet@google.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- net/ipv4/tcp.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -1186,7 +1186,7 @@ int tcp_sendmsg_locked(struct sock *sk, flags = msg->msg_flags;
if (flags & MSG_ZEROCOPY && size && sock_flag(sk, SOCK_ZEROCOPY)) { - if (sk->sk_state != TCP_ESTABLISHED) { + if ((1 << sk->sk_state) & ~(TCPF_ESTABLISHED | TCPF_CLOSE_WAIT)) { err = -EINVAL; goto out_err; }