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Commit 1f3db25d authored by Mike Snitzer's avatar Mike Snitzer Committed by Alasdair G Kergon
Browse files

dm thin metadata: remove incorrect close_device on creation error paths 



The __open_device() error paths in __create_thin() and __create_snap()
incorrectly call __close_device() even if td was not initialized by
__open_device().  Remove this.

Also document __open_device() return values, remove a redundant
td->changed = 1 in __create_thin(), and insert an additional
safeguard against creating an already-existing device.

Signed-off-by: default avatarMike Snitzer <snitzer@redhat.com>
Cc: stable@kernel.org
Signed-off-by: default avatarAlasdair G Kergon <agk@redhat.com>
parent 1212268f

drivers/md/dm-thin-metadata.c

+17 −5
Original line number Diff line number Diff line
@@ -789,6 +789,11 @@ int dm_pool_metadata_close(struct dm_pool_metadata *pmd) 
	return 0;

}



/*

 * __open_device: Returns @td corresponding to device with id @dev,

 * creating it if @create is set and incrementing @td->open_count.

 * On failure, @td is undefined.

 */

static int __open_device(struct dm_pool_metadata *pmd,

			 dm_thin_id dev, int create,

			 struct dm_thin_device **td)
@@ -799,10 +804,16 @@ static int __open_device(struct dm_pool_metadata *pmd, 
	struct disk_device_details details_le;



	/*

	 * Check the device isn't already open.

	 * If the device is already open, return it.

	 */

	list_for_each_entry(td2, &pmd->thin_devices, list)

		if (td2->id == dev) {

			/*

			 * May not create an already-open device.

			 */

			if (create)

				return -EEXIST;



			td2->open_count++;

			*td = td2;

			return 0;
@@ -817,6 +828,9 @@ static int __open_device(struct dm_pool_metadata *pmd, 
		if (r != -ENODATA || !create)

			return r;



		/*

		 * Create new device.

		 */

		changed = 1;

		details_le.mapped_blocks = 0;

		details_le.transaction_id = cpu_to_le64(pmd->trans_id);
@@ -882,12 +896,10 @@ static int __create_thin(struct dm_pool_metadata *pmd, 


	r = __open_device(pmd, dev, 1, &td);

	if (r) {

		__close_device(td);

		dm_btree_remove(&pmd->tl_info, pmd->root, &key, &pmd->root);

		dm_btree_del(&pmd->bl_info, dev_root);

		return r;

	}

	td->changed = 1;

	__close_device(td);



	return r;
@@ -967,14 +979,14 @@ static int __create_snap(struct dm_pool_metadata *pmd, 
		goto bad;



	r = __set_snapshot_details(pmd, td, origin, pmd->time);

	__close_device(td);



	if (r)

		goto bad;



	__close_device(td);

	return 0;



bad:

	__close_device(td);

	dm_btree_remove(&pmd->tl_info, pmd->root, &key, &pmd->root);

	dm_btree_remove(&pmd->details_info, pmd->details_root,

			&key, &pmd->details_root);