Re: [PATCH] xfs_repair: allow '/' in attribute names

["Darrick J. Wong" <darrick.wong@oracle.com>]

On Thu, Jan 03, 2019 at 03:27:26PM -0600, Eric Sandeen wrote:
> On 1/3/19 3:20 PM, Dave Chinner wrote:
> > On Thu, Jan 03, 2019 at 01:15:56PM -0600, Eric Sandeen wrote:
> >> For some reason, since the earliest days of XFS, a '/' character
> >> in an extended attribute name has been treated as corruption by
> >> xfs_repair.  This despite nothing in other userspace tools or the
> >> kernel having this restriction.
> >>
> >> My best guess is that this was an unintentional leftover from
> >> common code between dirs & attrs in the "da" code, and there has
> >> never been a good reason for it.
> >>
> >> Since userspace and kernelspace allow such a name to be set,
> >> listed, and read, it seems wrong to flag it as corruption.
> >> So, make this test conditional on whether we're validating a name
> >> in a dir, as opposed to the name of an attr.
> > 
> > Sounds fair.
> > 
> >> Signed-off-by: Eric Sandeen <sandeen@redhat.com>
> >> ---
> >>
> >>
> >> diff --git a/repair/attr_repair.c b/repair/attr_repair.c
> >> index 1d04500..2f6f7ef 100644
> >> --- a/repair/attr_repair.c
> >> +++ b/repair/attr_repair.c
> >> @@ -292,11 +292,9 @@ process_shortform_attr(
> >>  			}
> >>  		}
> >>  
> >> -		/* namecheck checks for / and null terminated for file names.
> >> -		 * attributes names currently follow the same rules.
> >> -		*/
> >> +		/* namecheck checks for null chars in attr names. */
> >>  		if (namecheck((char *)&currententry->nameval[0],
> >> -						currententry->namelen))  {
> >> +						currententry->namelen, false)) {
> > 
> > Hmmmm. that's kinda messy. How about:
> > 
> > /* attr_namecheck checks for null chars in attr names. */
> > bool
> > attr_namecheck(
> > 	uint8_t	name,
> > 	int	length)
> > {
> > 	return namecheck((char *)name, length, false);
> > }
> 
> Ok, good idea.

Can you put the dir/attr name verifier function(s) into libxfs so I can
reuse it in scrub instead of opencoding the same in there?  Pretty
please? :D

--D

> -Eric