From: Christoph Hellwig <hch@xxxxxx> [ Upstream commit 1f90307e5f0d7bc9a336ead528f616a5df8e5944 ] Disallow setting the blk-mq state on any queue that is already dying as setting the state even then is a bad idea, and remove the now unused QUEUE_FLAG_DEAD flag. Signed-off-by: Christoph Hellwig <hch@xxxxxx> Reviewed-by: Hannes Reinecke <hare@xxxxxxx> Link: https://lore.kernel.org/r/20220619060552.1850436-4-hch@xxxxxx Signed-off-by: Jens Axboe <axboe@xxxxxxxxx> Stable-dep-of: 8fe4ce5836e9 ("scsi: core: Fix a use-after-free") Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- block/blk-core.c | 3 --- block/blk-mq-debugfs.c | 8 +++----- include/linux/blkdev.h | 2 -- 3 files changed, 3 insertions(+), 10 deletions(-) diff --git a/block/blk-core.c b/block/blk-core.c index cc6fbcb6d252..76f070c3a3b0 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -313,9 +313,6 @@ void blk_cleanup_queue(struct request_queue *q) * after draining finished. */ blk_freeze_queue(q); - - blk_queue_flag_set(QUEUE_FLAG_DEAD, q); - blk_sync_queue(q); if (queue_is_mq(q)) { blk_mq_cancel_work_sync(q); diff --git a/block/blk-mq-debugfs.c b/block/blk-mq-debugfs.c index 61f179e5f151..28adb01f6441 100644 --- a/block/blk-mq-debugfs.c +++ b/block/blk-mq-debugfs.c @@ -116,7 +116,6 @@ static const char *const blk_queue_flag_name[] = { QUEUE_FLAG_NAME(NOXMERGES), QUEUE_FLAG_NAME(ADD_RANDOM), QUEUE_FLAG_NAME(SAME_FORCE), - QUEUE_FLAG_NAME(DEAD), QUEUE_FLAG_NAME(INIT_DONE), QUEUE_FLAG_NAME(STABLE_WRITES), QUEUE_FLAG_NAME(POLL), @@ -151,11 +150,10 @@ static ssize_t queue_state_write(void *data, const char __user *buf, char opbuf[16] = { }, *op; /* - * The "state" attribute is removed after blk_cleanup_queue() has called - * blk_mq_free_queue(). Return if QUEUE_FLAG_DEAD has been set to avoid - * triggering a use-after-free. + * The "state" attribute is removed when the queue is removed. Don't + * allow setting the state on a dying queue to avoid a use-after-free. */ - if (blk_queue_dead(q)) + if (blk_queue_dying(q)) return -ENOENT; if (count >= sizeof(opbuf)) { diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 62e3ff52ab03..76f77eed58c3 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -559,7 +559,6 @@ struct request_queue { #define QUEUE_FLAG_NOXMERGES 9 /* No extended merges */ #define QUEUE_FLAG_ADD_RANDOM 10 /* Contributes to random pool */ #define QUEUE_FLAG_SAME_FORCE 12 /* force complete on same CPU */ -#define QUEUE_FLAG_DEAD 13 /* queue tear-down finished */ #define QUEUE_FLAG_INIT_DONE 14 /* queue is initialized */ #define QUEUE_FLAG_STABLE_WRITES 15 /* don't modify blks until WB is done */ #define QUEUE_FLAG_POLL 16 /* IO polling enabled if set */ @@ -587,7 +586,6 @@ bool blk_queue_flag_test_and_set(unsigned int flag, struct request_queue *q); #define blk_queue_stopped(q) test_bit(QUEUE_FLAG_STOPPED, &(q)->queue_flags) #define blk_queue_dying(q) test_bit(QUEUE_FLAG_DYING, &(q)->queue_flags) #define blk_queue_has_srcu(q) test_bit(QUEUE_FLAG_HAS_SRCU, &(q)->queue_flags) -#define blk_queue_dead(q) test_bit(QUEUE_FLAG_DEAD, &(q)->queue_flags) #define blk_queue_init_done(q) test_bit(QUEUE_FLAG_INIT_DONE, &(q)->queue_flags) #define blk_queue_nomerges(q) test_bit(QUEUE_FLAG_NOMERGES, &(q)->queue_flags) #define blk_queue_noxmerges(q) \ -- 2.35.1
