summaryrefslogtreecommitdiffstats
path: root/net/can
diff options
context:
space:
mode:
authorOliver Hartkopp <socketcan@hartkopp.net>2022-04-05 19:51:12 +0200
committerMarc Kleine-Budde <mkl@pengutronix.de>2022-04-17 17:21:22 +0200
commitd73497081710c876c3c61444445512989e102152 (patch)
tree2a2c9c2f7fdb78e3c4b804c51dd2688a28d72605 /net/can
parent49aefd131739df552f83c566d0665744c30b1d70 (diff)
downloadlinux-d73497081710c876c3c61444445512989e102152.tar.bz2
can: isotp: stop timeout monitoring when no first frame was sent
The first attempt to fix a the 'impossible' WARN_ON_ONCE(1) in isotp_tx_timer_handler() focussed on the identical CAN IDs created by the syzbot reproducer and lead to upstream fix/commit 3ea566422cbd ("can: isotp: sanitize CAN ID checks in isotp_bind()"). But this did not catch the root cause of the wrong tx.state in the tx_timer handler. In the isotp 'first frame' case a timeout monitoring needs to be started before the 'first frame' is send. But when this sending failed the timeout monitoring for this specific frame has to be disabled too. Otherwise the tx_timer is fired with the 'warn me' tx.state of ISOTP_IDLE. Fixes: e057dd3fc20f ("can: add ISO 15765-2:2016 transport protocol") Link: https://lore.kernel.org/all/20220405175112.2682-1-socketcan@hartkopp.net Reported-by: syzbot+2339c27f5c66c652843e@syzkaller.appspotmail.com Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net> Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Diffstat (limited to 'net/can')
-rw-r--r--net/can/isotp.c10
1 files changed, 9 insertions, 1 deletions
diff --git a/net/can/isotp.c b/net/can/isotp.c
index bafb0fb5f0e0..ff5d7870294e 100644
--- a/net/can/isotp.c
+++ b/net/can/isotp.c
@@ -906,6 +906,7 @@ static int isotp_sendmsg(struct socket *sock, struct msghdr *msg, size_t size)
struct canfd_frame *cf;
int ae = (so->opt.flags & CAN_ISOTP_EXTEND_ADDR) ? 1 : 0;
int wait_tx_done = (so->opt.flags & CAN_ISOTP_WAIT_TX_DONE) ? 1 : 0;
+ s64 hrtimer_sec = 0;
int off;
int err;
@@ -1004,7 +1005,9 @@ static int isotp_sendmsg(struct socket *sock, struct msghdr *msg, size_t size)
isotp_create_fframe(cf, so, ae);
/* start timeout for FC */
- hrtimer_start(&so->txtimer, ktime_set(1, 0), HRTIMER_MODE_REL_SOFT);
+ hrtimer_sec = 1;
+ hrtimer_start(&so->txtimer, ktime_set(hrtimer_sec, 0),
+ HRTIMER_MODE_REL_SOFT);
}
/* send the first or only CAN frame */
@@ -1017,6 +1020,11 @@ static int isotp_sendmsg(struct socket *sock, struct msghdr *msg, size_t size)
if (err) {
pr_notice_once("can-isotp: %s: can_send_ret %pe\n",
__func__, ERR_PTR(err));
+
+ /* no transmission -> no timeout monitoring */
+ if (hrtimer_sec)
+ hrtimer_cancel(&so->txtimer);
+
goto err_out_drop;
}