Patch "dccp: don't restart ccid2_hc_tx_rto_expire() if sk in closed state" 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

dccp: don't restart ccid2_hc_tx_rto_expire() if sk in closed state

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:
dccp-don-t-restart-ccid2_hc_tx_rto_expire-if-sk-in-closed-state.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: Alexey Kodanev <[email protected]>
Date: Fri, 26 Jan 2018 15:14:16 +0300
Subject: dccp: don't restart ccid2_hc_tx_rto_expire() if sk in closed state

From: Alexey Kodanev <[email protected]>

[ Upstream commit dd5684ecae3bd8e44b644f50e2c12c7e57fdfef5 ]

ccid2_hc_tx_rto_expire() timer callback always restarts the timer again and can run indefinitely (unless it is stopped outside), and after commit 120e9dabaf55 ("dccp: defer ccid_hc_tx_delete() at dismantle time"), which moved ccid_hc_tx_delete() (also includes sk_stop_timer()) from dccp_destroy_sock() to sk_destruct(), this started to happen quite often. The timer prevents releasing the socket, as a result, sk_destruct() won't be called.

Found with LTP/dccp_ipsec tests running on the bonding device, which later couldn't be unloaded after the tests were completed:

unregister_netdevice: waiting for bond0 to become free. Usage count = 148

---
 net/dccp/ccids/ccid2.c |    3 +++
 1 file changed, 3 insertions(+)

@@ -140,6 +140,9 @@ static void ccid2_hc_tx_rto_expire(unsig
 
 	ccid2_pr_debug("RTO_EXPIRE\n");
 
+	if (sk->sk_state == DCCP_CLOSED)
+		goto out;
+
 	/* back-off timer */
 	hc->tx_rto <<= 1;
 	if (hc->tx_rto > DCCP_RTO_MAX)

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

queue-4.14/dccp-don-t-restart-ccid2_hc_tx_rto_expire-if-sk-in-closed-state.patch queue-4.14/ip6_gre-init-dev-mtu-and-dev-hard_header_len-correctly.patch