From dd5684ecae3bd8e44b644f50e2c12c7e57fdfef5 Mon Sep 17 00:00:00 2001 From: Alexey Kodanev Date: Fri, 26 Jan 2018 15:14:16 +0300 Subject: [PATCH] dccp: don't restart ccid2_hc_tx_rto_expire() if sk in closed state 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 Reviewed-by: Eric Dumazet Signed-off-by: David S. Miller --- net/dccp/ccids/ccid2.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/net/dccp/ccids/ccid2.c b/net/dccp/ccids/ccid2.c index 1c75cd1255f6..92d016e87816 100644 --- a/net/dccp/ccids/ccid2.c +++ b/net/dccp/ccids/ccid2.c @@ -140,6 +140,9 @@ static void ccid2_hc_tx_rto_expire(struct timer_list *t) 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) -- 2.39.5