From 647a20d5cad7477033bc021ec9dd75edf4bbf9a0 Mon Sep 17 00:00:00 2001 From: Mike Snitzer Date: Tue, 17 Nov 2015 14:11:34 -0500 Subject: dm: do not reuse dm_blk_ioctl block_device input as local variable (Ab)using the @bdev passed to dm_blk_ioctl() opens the potential for targets' .prepare_ioctl to fail if they go on to check the bdev for !NULL. Fixes: e56f81e0b01e ("dm: refactor ioctl handling") Reported-by: Junichi Nomura Signed-off-by: Mike Snitzer --- drivers/md/dm.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) (limited to 'drivers/md') diff --git a/drivers/md/dm.c b/drivers/md/dm.c index fabd5d8fd559..5df40480228b 100644 --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -603,9 +603,10 @@ static int dm_blk_ioctl(struct block_device *bdev, fmode_t mode, { struct mapped_device *md = bdev->bd_disk->private_data; struct dm_target *tgt; + struct block_device *tgt_bdev = NULL; int srcu_idx, r; - r = dm_get_live_table_for_ioctl(md, &tgt, &bdev, &mode, &srcu_idx); + r = dm_get_live_table_for_ioctl(md, &tgt, &tgt_bdev, &mode, &srcu_idx); if (r < 0) return r; @@ -620,7 +621,7 @@ static int dm_blk_ioctl(struct block_device *bdev, fmode_t mode, goto out; } - r = __blkdev_driver_ioctl(bdev, mode, cmd, arg); + r = __blkdev_driver_ioctl(tgt_bdev, mode, cmd, arg); out: dm_put_live_table(md, srcu_idx); return r; -- cgit v1.2.3-59-g8ed1b