1.In current process, all bio will set the BIO_THROTTLED flag after __blk_throtl_bio(). 2.If bio needs to be throttled, it will start the timer and stop submit bio directly. Bio will submit in blk_throtl_dispatch_work_fn() when the timer expires. But in the current process, if bio is throttled. The BIO_THROTTLED will be set to bio after timer start. If the bio has been completed, it may cause use-after-free. Fix this by move BIO_THROTTLED set before timer set. Signed-off-by: Laibin Qiu <qiulaibin@xxxxxxxxxx> --- block/blk-throttle.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/block/blk-throttle.c b/block/blk-throttle.c index 39bb6e68a9a2..ddfbff4465d5 100644 --- a/block/blk-throttle.c +++ b/block/blk-throttle.c @@ -2149,6 +2149,7 @@ bool __blk_throtl_bio(struct bio *bio) td->nr_queued[rw]++; throtl_add_bio_tg(bio, qn, tg); throttled = true; + bio_set_flag(bio, BIO_THROTTLED); /* * Update @tg's dispatch time and force schedule dispatch if @tg @@ -2163,7 +2164,6 @@ bool __blk_throtl_bio(struct bio *bio) out_unlock: spin_unlock_irq(&q->queue_lock); - bio_set_flag(bio, BIO_THROTTLED); #ifdef CONFIG_BLK_DEV_THROTTLING_LOW if (throttled || !td->track_bio_latency) -- 2.22.0
