From: Daniel Starke Date: Fri, 1 Jul 2022 06:16:50 +0000 (+0200) Subject: tty: n_gsm: fix packet re-transmission without open control channel X-Git-Tag: v5.15.73~1217 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=a7fa41552407f95cb520bc90b3cfe590344d323b;p=platform%2Fkernel%2Flinux-rpi.git tty: n_gsm: fix packet re-transmission without open control channel [ Upstream commit 4fae831b3a71fc5a44cc5c7d0b8c1267ee7659f5 ] In the current implementation control packets are re-transmitted even if the control channel closed down during T2. This is wrong. Check whether the control channel is open before re-transmitting any packets. Note that control channel open/close is handled by T1 and not T2 and remains unaffected by this. Fixes: e1eaea46bb40 ("tty: n_gsm line discipline") Signed-off-by: Daniel Starke Link: https://lore.kernel.org/r/20220701061652.39604-7-daniel.starke@siemens.com Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin --- diff --git a/drivers/tty/n_gsm.c b/drivers/tty/n_gsm.c index 56a3466..3f65990 100644 --- a/drivers/tty/n_gsm.c +++ b/drivers/tty/n_gsm.c @@ -1546,7 +1546,7 @@ static void gsm_control_retransmit(struct timer_list *t) spin_lock_irqsave(&gsm->control_lock, flags); ctrl = gsm->pending_cmd; if (ctrl) { - if (gsm->cretries == 0) { + if (gsm->cretries == 0 || !gsm->dlci[0] || gsm->dlci[0]->dead) { gsm->pending_cmd = NULL; ctrl->error = -ETIMEDOUT; ctrl->done = 1;