Patch "tcp: purge write queue upon RST" has been added to the 4.14-stable tree

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;a=summary

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 <[email protected]> know about it.

From: Soheil Hassas Yeganeh <[email protected]>
Date: Tue, 27 Feb 2018 18:32:18 -0500
Subject: tcp: purge write queue upon RST

From: Soheil Hassas Yeganeh <[email protected]>

[ 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.

---
 net/ipv4/tcp_input.c |    1 +
 1 file changed, 1 insertion(+)

@@ -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 [email protected] are

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