From: Coly Li colyli@suse.de
commit 8468f45091d2866affed6f6a7aecc20779139173 upstream.
In bcache_device_free(), pointer disk is referenced still in ida_simple_remove() after blk_cleanup_disk() gets called on this pointer. This may cause a potential panic by use-after-free on the disk pointer.
This patch fixes the problem by calling blk_cleanup_disk() after ida_simple_remove().
Fixes: bc70852fd104 ("bcache: convert to blk_alloc_disk/blk_cleanup_disk") Signed-off-by: Coly Li colyli@suse.de Cc: Christoph Hellwig hch@lst.de Cc: Hannes Reinecke hare@suse.de Cc: Ulf Hansson ulf.hansson@linaro.org Cc: stable@vger.kernel.org # v5.14+ Reviewed-by: Christoph Hellwig hch@lst.de Link: https://lore.kernel.org/r/20211103064917.67383-1-colyli@suse.de Signed-off-by: Jens Axboe axboe@kernel.dk Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/md/bcache/super.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/drivers/md/bcache/super.c +++ b/drivers/md/bcache/super.c @@ -885,9 +885,9 @@ static void bcache_device_free(struct bc bcache_device_detach(d);
if (disk) { - blk_cleanup_disk(disk); ida_simple_remove(&bcache_device_idx, first_minor_to_idx(disk->first_minor)); + blk_cleanup_disk(disk); }
bioset_exit(&d->bio_split);