3.2-stable review patch. If anyone has any objections, please let me know.
------------------ From: Mike Snitzer <[email protected]> commit 1f3db25d8be4ac50b897b39609802183ea68a514 upstream. 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: Mike Snitzer <[email protected]> Signed-off-by: Alasdair G Kergon <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- drivers/md/dm-thin-metadata.c | 22 +++++++++++++++++----- 1 file changed, 17 insertions(+), 5 deletions(-) --- a/drivers/md/dm-thin-metadata.c +++ b/drivers/md/dm-thin-metadata.c @@ -789,6 +789,11 @@ int dm_pool_metadata_close(struct dm_poo 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_ 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_ 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_ 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_ 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); -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
