diff options
| author | Curtis Klein <curtis.klein@hpe.com> | 2021-06-23 08:26:23 +0200 |
|---|---|---|
| committer | Wim Van Sebroeck <wim@linux-watchdog.org> | 2021-08-22 10:28:07 +0200 |
| commit | c7b178dae139f8857edc50888cfbf251cd974a38 (patch) | |
| tree | 8cf6ad286f48f6c3909c68100a609833bc8a500b /drivers/watchdog/watchdog_dev.c | |
| parent | watchdog: only run driver set_pretimeout op if device supports it (diff) | |
| download | linux-c7b178dae139f8857edc50888cfbf251cd974a38.tar.xz linux-c7b178dae139f8857edc50888cfbf251cd974a38.zip | |
watchdog: Fix NULL pointer dereference when releasing cdev
watchdog_hrtimer_pretimeout_stop needs the watchdog device to have a
valid pointer to the watchdog core data to stop the pretimeout hrtimer.
Therefore it needs to be called before the pointers are cleared in
watchdog_cdev_unregister.
Fixes: 7b7d2fdc8c3e ("watchdog: Add hrtimer-based pretimeout feature")
Reported-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Curtis Klein <curtis.klein@hpe.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/1624429583-5720-1-git-send-email-curtis.klein@hpe.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
Diffstat (limited to 'drivers/watchdog/watchdog_dev.c')
| -rw-r--r-- | drivers/watchdog/watchdog_dev.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/drivers/watchdog/watchdog_dev.c b/drivers/watchdog/watchdog_dev.c index 5bf795c1b346..f408967ff1a4 100644 --- a/drivers/watchdog/watchdog_dev.c +++ b/drivers/watchdog/watchdog_dev.c @@ -1096,6 +1096,8 @@ static void watchdog_cdev_unregister(struct watchdog_device *wdd) watchdog_stop(wdd); } + watchdog_hrtimer_pretimeout_stop(wdd); + mutex_lock(&wd_data->lock); wd_data->wdd = NULL; wdd->wd_data = NULL; @@ -1103,7 +1105,6 @@ static void watchdog_cdev_unregister(struct watchdog_device *wdd) hrtimer_cancel(&wd_data->timer); kthread_cancel_work_sync(&wd_data->work); - watchdog_hrtimer_pretimeout_stop(wdd); put_device(&wd_data->dev); } |