diff options
| author | Ming Lei <ming.lei@redhat.com> | 2025-05-05 22:17:57 +0800 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2025-05-06 07:43:43 -0600 |
| commit | 5c3d858cdc57196e6d438e5ad47a732216e81a9c (patch) | |
| tree | 64de3b466f9096140759c1ff8f43b0fae422d595 /block/blk-mq-sched.c | |
| parent | e25ee50dfab9fce77d2e0d89d2413b6c68015f97 (diff) | |
block: fail to show/store elevator sysfs attribute if elevator is dying
Prepare for moving elv_register[unregister]_queue out of elevator_lock
& queue freezing, so we may have to call elv_unregister_queue() after
elevator ->exit() is called, then there is small window for user to
call into ->show()/store(), and user-after-free can be caused.
Fail to show/store elevator sysfs attribute if elevator is dying by
adding one new flag of ELEVATOR_FLAG_DYNG, which is protected by
elevator ->sysfs_lock.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Nilay Shroff <nilay@linux.ibm.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Link: https://lore.kernel.org/r/20250505141805.2751237-20-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'block/blk-mq-sched.c')
| -rw-r--r-- | block/blk-mq-sched.c | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/block/blk-mq-sched.c b/block/blk-mq-sched.c index 336a15ffecfa..55a0fd105147 100644 --- a/block/blk-mq-sched.c +++ b/block/blk-mq-sched.c @@ -551,5 +551,6 @@ void blk_mq_exit_sched(struct request_queue *q, struct elevator_queue *e) if (e->type->ops.exit_sched) e->type->ops.exit_sched(e); blk_mq_sched_tags_teardown(q, flags); + set_bit(ELEVATOR_FLAG_DYING, &q->elevator->flags); q->elevator = NULL; } |