[PATCH 0/2] smack: fix two bugs in setting task label

[Konstantin Andreev]

Casey Schaufler, 11/03/2025:
> On 3/6/2025 2:43 PM, Konstantin Andreev wrote:
>> These two patches have distinct subjects,
>> but work on the same object,
>>    security/smack/smack_lsm.c`do_setattr()
>> and the second patch partially overwrites first,
>> so I combine them in a series.
>>
>> Konstantin Andreev (2):
>>    smack: fix bug: unprivileged task can create labels
>>    smack: fix bug: setting task label silently ignores input garbage
> 
> There is a problem with this change. Some applications include a
> trailing '\0' when writing to /proc/self/attr/smack/current, which
> fails with this change. It may not be "correct", but it is expected.

Understood. Given this, for any "label"
three input variants should be accepted:

   "label"    (5 bytes)
   "label\0"  (6 bytes)
   "label\n"  (6 bytes)

but not

   "label\0\n"
   "label\n\0"
   etc...

right?

Thank you for paying attention.

--
Konstantin Andreev