Btrfs: do not overwrite scrub error with fault error in scrub ioctl

If scrub returned an error and then the copy_to_user() call did not
succeed, we would overwrite the error returned by scrub with -EFAULT.
Fix that by calling copy_to_user() only if btrfs_scrub_dev() returned
success.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This commit is contained in:
Filipe Manana 2018-12-14 19:50:17 +00:00 committed by David Sterba
parent bc9a8bf79c
commit 06fe39ab15

View File

@ -4381,7 +4381,7 @@ static long btrfs_ioctl_scrub(struct file *file, void __user *arg)
&sa->progress, sa->flags & BTRFS_SCRUB_READONLY,
0);
if (copy_to_user(arg, sa, sizeof(*sa)))
if (ret == 0 && copy_to_user(arg, sa, sizeof(*sa)))
ret = -EFAULT;
if (!(sa->flags & BTRFS_SCRUB_READONLY))