Patch "tcp: fix access to sk->sk_state in tcp_poll()" has been added to the 4.11-stable tree

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

    tcp: fix access to sk->sk_state in tcp_poll()

to the 4.11-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-fix-access-to-sk-sk_state-in-tcp_poll.patch
and it can be found in the queue-4.11 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Davide Caratti <[email protected]>
Date: Wed, 26 Apr 2017 19:07:35 +0200
Subject: tcp: fix access to sk->sk_state in tcp_poll()

From: Davide Caratti <[email protected]>

[ Upstream commit d68be71ea14d609a5f31534003319be5db422595 ]

avoid direct access to sk->sk_state when tcp_poll() is called on a socket using active TCP fastopen with deferred connect. Use local variable 'state', which stores the result of sk_state_load(), like it was done in commit 00fd38d938db ("tcp: ensure proper barriers in lockless contexts").

---
 net/ipv4/tcp.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

@@ -533,7 +533,7 @@ unsigned int tcp_poll(struct file *file,
 
 		if (tp->urg_data & TCP_URG_VALID)
 			mask |= POLLPRI;
-	} else if (sk->sk_state == TCP_SYN_SENT && inet_sk(sk)->defer_connect) {
+	} else if (state == TCP_SYN_SENT && inet_sk(sk)->defer_connect) {
 		/* Active TCP fastopen socket with defer_connect
 		 * Return POLLOUT so application can call write()
 		 * in order for kernel to generate SYN+data

Patches currently in stable-queue which might be from [email protected] are

queue-4.11/tcp-fix-access-to-sk-sk_state-in-tcp_poll.patch