This is a note to let you know that I've just added the patch titled Btrfs: fix potential use-after-free for cloned bio to the 4.9-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: btrfs-fix-potential-use-after-free-for-cloned-bio.patch and it can be found in the queue-4.9 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From foo@baz Thu Oct 5 10:28:31 CEST 2017 From: Liu Bo <bo.li.liu@xxxxxxxxxx> Date: Mon, 10 Apr 2017 12:36:26 -0700 Subject: Btrfs: fix potential use-after-free for cloned bio From: Liu Bo <bo.li.liu@xxxxxxxxxx> [ Upstream commit a967efb30b3afa3d858edd6a17f544f9e9e46eea ] KASAN reports that there is a use-after-free case of bio in btrfs_map_bio. If we need to submit IOs to several disks at a time, the original bio would get cloned and mapped to the destination disk, but we really should use the original bio instead of a cloned bio to do the sanity check because cloned bios are likely to be freed by its endio. Reported-by: Diego <diegocg@xxxxxxxxx> Signed-off-by: Liu Bo <bo.li.liu@xxxxxxxxxx> Reviewed-by: David Sterba <dsterba@xxxxxxxx> Signed-off-by: David Sterba <dsterba@xxxxxxxx> Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- fs/btrfs/volumes.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -6226,7 +6226,7 @@ int btrfs_map_bio(struct btrfs_root *roo for (dev_nr = 0; dev_nr < total_devs; dev_nr++) { dev = bbio->stripes[dev_nr].dev; if (!dev || !dev->bdev || - (bio_op(bio) == REQ_OP_WRITE && !dev->writeable)) { + (bio_op(first_bio) == REQ_OP_WRITE && !dev->writeable)) { bbio_error(bbio, first_bio, logical); continue; } Patches currently in stable-queue which might be from bo.li.liu@xxxxxxxxxx are queue-4.9/btrfs-fix-potential-use-after-free-for-cloned-bio.patch queue-4.9/btrfs-fix-segmentation-fault-when-doing-dio-read.patch