This is a note to let you know that I've just added the patch titled
bcache: fix use-after-free problem in bcache_device_free()
to the 5.15-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
bcache-fix-use-after-free-problem-in-bcache_device_free.patch
and it can be found in the queue-5.15 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 8468f45091d2866affed6f6a7aecc20779139173 Mon Sep 17 00:00:00 2001
From: Coly Li <colyli@xxxxxxx>
Date: Wed, 3 Nov 2021 14:49:17 +0800
Subject: bcache: fix use-after-free problem in bcache_device_free()
From: Coly Li <colyli@xxxxxxx>
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@xxxxxxx>
Cc: Christoph Hellwig <hch@xxxxxx>
Cc: Hannes Reinecke <hare@xxxxxxx>
Cc: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx # v5.14+
Reviewed-by: Christoph Hellwig <hch@xxxxxx>
Link: https://lore.kernel.org/r/20211103064917.67383-1-colyli@xxxxxxx
Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
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);
Patches currently in stable-queue which might be from colyli@xxxxxxx are
queue-5.15/bcache-fix-use-after-free-problem-in-bcache_device_free.patch
queue-5.15/bcache-revert-bcache-use-bvec_virt.patch
