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

[Eric Sandeen <sandeen@redhat.com>]

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.

-Eric