Btrfs: do not overwrite error return value in scrub progress ioctl

If the call to btrfs_scrub_progress() failed we would overwrite the error
returned to user space with -EFAULT if the call to copy_to_user() failed
as well. Fix that by calling copy_to_user() only if btrfs_scrub_progress()
returned success.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This commit is contained in:
Filipe Manana 2018-12-14 19:45:13 +00:00 committed by David Sterba
parent 06fe39ab15
commit 4fa99b008f

View file

@ -4414,7 +4414,7 @@ static long btrfs_ioctl_scrub_progress(struct btrfs_fs_info *fs_info,
ret = btrfs_scrub_progress(fs_info, sa->devid, &sa->progress);
if (copy_to_user(arg, sa, sizeof(*sa)))
if (ret == 0 && copy_to_user(arg, sa, sizeof(*sa)))
ret = -EFAULT;
kfree(sa);