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 120e9dabaf ("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: 2a91aa3967 ("[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>
This commit is contained in:
Alexey Kodanev 2018-01-26 15:14:16 +03:00 committed by David S. Miller
parent 1e19c4d689
commit dd5684ecae

View File

@ -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)