From 78601726d4a59a291acc5a52da1d3a0a6831e4e8 Mon Sep 17 00:00:00 2001 From: Vincent Whitchurch Date: Thu, 19 May 2022 11:19:25 +0200 Subject: [PATCH] iio: trigger: sysfs: fix use-after-free on remove Ensure that the irq_work has completed before the trigger is freed. ================================================================== BUG: KASAN: use-after-free in irq_work_run_list Read of size 8 at addr 0000000064702248 by task python3/25 Call Trace: irq_work_run_list irq_work_tick update_process_times tick_sched_handle tick_sched_timer __hrtimer_run_queues hrtimer_interrupt Allocated by task 25: kmem_cache_alloc_trace iio_sysfs_trig_add dev_attr_store sysfs_kf_write kernfs_fop_write_iter new_sync_write vfs_write ksys_write sys_write Freed by task 25: kfree iio_sysfs_trig_remove dev_attr_store sysfs_kf_write kernfs_fop_write_iter new_sync_write vfs_write ksys_write sys_write ================================================================== Fixes: f38bc926d022 ("staging:iio:sysfs-trigger: Use irq_work to properly active trigger") Signed-off-by: Vincent Whitchurch Reviewed-by: Lars-Peter Clausen Link: https://lore.kernel.org/r/20220519091925.1053897-1-vincent.whitchurch@axis.com Cc: Signed-off-by: Jonathan Cameron --- drivers/iio/trigger/iio-trig-sysfs.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/iio/trigger/iio-trig-sysfs.c b/drivers/iio/trigger/iio-trig-sysfs.c index 2a4b758..3d911c2 100644 --- a/drivers/iio/trigger/iio-trig-sysfs.c +++ b/drivers/iio/trigger/iio-trig-sysfs.c @@ -191,6 +191,7 @@ static int iio_sysfs_trigger_remove(int id) } iio_trigger_unregister(t->trig); + irq_work_sync(&t->work); iio_trigger_free(t->trig); list_del(&t->l); -- 2.7.4