This is a note to let you know that I've just added the patch titled

tcp: purge write queue upon RST

to the 4.14-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git%3Ba=su...

The filename of the patch is: tcp-purge-write-queue-upon-rst.patch and it can be found in the queue-4.14 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let stable@vger.kernel.org know about it.

From foo@baz Tue Mar 6 19:02:12 PST 2018

From: Soheil Hassas Yeganeh soheil@google.com Date: Tue, 27 Feb 2018 18:32:18 -0500 Subject: tcp: purge write queue upon RST

From: Soheil Hassas Yeganeh soheil@google.com

[ Upstream commit a27fd7a8ed3856faaf5a2ff1c8c5f00c0667aaa0 ]

When the connection is reset, there is no point in keeping the packets on the write queue until the connection is closed.

RFC 793 (page 70) and RFC 793-bis (page 64) both suggest purging the write queue upon RST: https://tools.ietf.org/html/draft-ietf-tcpm-rfc793bis-07

Moreover, this is essential for a correct MSG_ZEROCOPY implementation, because userspace cannot call close(fd) before receiving zerocopy signals even when the connection is reset.

Fixes: f214f915e7db ("tcp: enable MSG_ZEROCOPY") Signed-off-by: Soheil Hassas Yeganeh soheil@google.com Reviewed-by: Eric Dumazet edumazet@google.com Signed-off-by: Yuchung Cheng ycheng@google.com Signed-off-by: Neal Cardwell ncardwell@google.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- net/ipv4/tcp_input.c | 1 + 1 file changed, 1 insertion(+)

--- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -4011,6 +4011,7 @@ void tcp_reset(struct sock *sk) /* This barrier is coupled with smp_rmb() in tcp_poll() */ smp_wmb();

+ tcp_write_queue_purge(sk); tcp_done(sk);

if (!sock_flag(sk, SOCK_DEAD))

Patches currently in stable-queue which might be from soheil@google.com are

queue-4.14/tcp-purge-write-queue-upon-rst.patch queue-4.14/tcp_bbr-better-deal-with-suboptimal-gso.patch