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 4.4-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: dccp-don-t-restart-ccid2_hc_tx_rto_expire-if-sk-in-closed-state.patch and it can be found in the queue-4.4 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 Mon Jan 29 10:14:57 CET 2018

From: Alexey Kodanev alexey.kodanev@oracle.com 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 alexey.kodanev@oracle.com

[ 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

Fixes: 2a91aa396739 ("[DCCP] CCID2: Initial CCID2 (TCP-Like) implementation") Signed-off-by: Alexey Kodanev alexey.kodanev@oracle.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/dccp/ccids/ccid2.c | 3 +++ 1 file changed, 3 insertions(+)

--- a/net/dccp/ccids/ccid2.c +++ b/net/dccp/ccids/ccid2.c @@ -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 alexey.kodanev@oracle.com are

queue-4.4/dccp-don-t-restart-ccid2_hc_tx_rto_expire-if-sk-in-closed-state.patch