| Message ID | 1491852986-7133-1-git-send-email-bo.li.liu@oracle.com (mailing list archive) |
|---|---|
| State | Accepted |
| Headers | show |
On Mon, Apr 10, 2017 at 12:36:26PM -0700, Liu Bo wrote: > 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@gmail.com> > Signed-off-by: Liu Bo <bo.li.liu@oracle.com> Reviewed-by: David Sterba <dsterba@suse.com> -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c index 73d56ee..ab8a66d 100644 --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -6213,7 +6213,7 @@ int btrfs_map_bio(struct btrfs_fs_info *fs_info, struct bio *bio, 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; }
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@gmail.com> Signed-off-by: Liu Bo <bo.li.liu@oracle.com> --- fs/btrfs/volumes.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)