iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

Btrfs: fix return value on rename exchange failure

Browse Source 
commit c5b4a50b74018b3677098151ec5f4fce07d5e6a0 upstream.

If we failed during a rename exchange operation after starting/joining a
transaction, we would end up replacing the return value, stored in the
local 'ret' variable, with the return value from btrfs_end_transaction().
So this could end up returning 0 (success) to user space despite the
operation having failed and aborted the transaction, because if there are
multiple tasks having a reference on the transaction at the time
btrfs_end_transaction() is called by the rename exchange, that function
returns 0 (otherwise it returns -EIO and not the original error value).
So fix this by not overwriting the return value on error after getting
a transaction handle.

Fixes: cdd1fedf8261 ("btrfs: add support for RENAME_EXCHANGE and RENAME_WHITEOUT")
CC: stable@vger.kernel.org # 4.9+
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Filipe Manana 2018-06-11 19:24:16 +01:00 committed by Greg Kroah-Hartman
parent af20e4eccc
commit 6101eea47b
1 changed files with 3 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
fs/btrfs/inode.c
View File

@ -9769,6 +9769,7 @@ static int btrfs_rename_exchange(struct inode *old_dir,
u64 new_idx = 0;
u64 root_objectid;
int ret;
int ret2;
bool root_log_pinned = false;
bool dest_log_pinned = false;
@ -9965,7 +9966,8 @@ out_fail:
dest_log_pinned = false;
}
}
ret = btrfs_end_transaction(trans);
ret2 = btrfs_end_transaction(trans);
ret = ret ? ret : ret2;
out_notrans:
if (new_ino == BTRFS_FIRST_FREE_OBJECTID)
up_read(&fs_info->subvol_sem);