From ec8013beddd717d1740cfefb1a9b900deef85462 Mon Sep 17 00:00:00 2001 From: Paolo Bonzini Date: Thu, 12 Jan 2012 16:01:29 +0100 Subject: dm: do not forward ioctls from logical volumes to the underlying device A logical volume can map to just part of underlying physical volume. In this case, it must be treated like a partition. Based on a patch from Alasdair G Kergon. Cc: Alasdair G Kergon Cc: dm-devel@redhat.com Signed-off-by: Paolo Bonzini Signed-off-by: Linus Torvalds --- drivers/md/dm-linear.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) (limited to 'drivers/md/dm-linear.c') diff --git a/drivers/md/dm-linear.c b/drivers/md/dm-linear.c index 3921e3bb43c1..9728839f844a 100644 --- a/drivers/md/dm-linear.c +++ b/drivers/md/dm-linear.c @@ -116,7 +116,17 @@ static int linear_ioctl(struct dm_target *ti, unsigned int cmd, unsigned long arg) { struct linear_c *lc = (struct linear_c *) ti->private; - return __blkdev_driver_ioctl(lc->dev->bdev, lc->dev->mode, cmd, arg); + struct dm_dev *dev = lc->dev; + int r = 0; + + /* + * Only pass ioctls through if the device sizes match exactly. + */ + if (lc->start || + ti->len != i_size_read(dev->bdev->bd_inode) >> SECTOR_SHIFT) + r = scsi_verify_blk_ioctl(NULL, cmd); + + return r ? : __blkdev_driver_ioctl(dev->bdev, dev->mode, cmd, arg); } static int linear_merge(struct dm_target *ti, struct bvec_merge_data *bvm, -- cgit v1.2.3