[PATCH] linux: return UNSUPPORTED in tst-mount if support_become_root fails

[Carlos O'Donell]

On 7/14/22 07:24, Adhemerval Zanella Netto via Libc-alpha wrote:
> 
> 
> On 14/07/22 00:23, Michael Hudson-Doyle via Libc-alpha wrote:
>> Otherwise the test fails if run in a chroot by a non-root user:
>>
>> warning: could not become root outside namespace (Operation not permitted)
>> ../sysdeps/unix/sysv/linux/tst-mount.c:36: numeric comparison failure
>>    left: 1 (0x1); from: errno
>>   right: 19 (0x13); from: ENODEV
>> error: ../sysdeps/unix/sysv/linux/tst-mount.c:39: not true: fd != -1
>> error: ../sysdeps/unix/sysv/linux/tst-mount.c:46: not true: r != -1
>> error: ../sysdeps/unix/sysv/linux/tst-mount.c:48: not true: r != -1
>> ../sysdeps/unix/sysv/linux/tst-mount.c:52: numeric comparison failure
>>    left: 1 (0x1); from: errno
>>   right: 9 (0x9); from: EBADF
>> error: ../sysdeps/unix/sysv/linux/tst-mount.c:55: not true: mfd != -1
>> ../sysdeps/unix/sysv/linux/tst-mount.c:58: numeric comparison failure
>>    left: 1 (0x1); from: errno
>>   right: 2 (0x2); from: ENOENT
>> error: ../sysdeps/unix/sysv/linux/tst-mount.c:61: not true: r != -1
>> ../sysdeps/unix/sysv/linux/tst-mount.c:65: numeric comparison failure
>>    left: 1 (0x1); from: errno
>>   right: 2 (0x2); from: ENOENT
>> error: ../sysdeps/unix/sysv/linux/tst-mount.c:68: not true: pfd != -1
>> error: ../sysdeps/unix/sysv/linux/tst-mount.c:75: not true: fd_tree != -1
>> ../sysdeps/unix/sysv/linux/tst-mount.c:88: numeric comparison failure
>>    left: 1 (0x1); from: errno
>>   right: 38 (0x26); from: ENOSYS
>> error: 12 test failures
>> ---
>>  sysdeps/unix/sysv/linux/tst-mount.c | 3 ++-
>>  1 file changed, 2 insertions(+), 1 deletion(-)
>>
>> diff --git a/sysdeps/unix/sysv/linux/tst-mount.c b/sysdeps/unix/sysv/linux/tst-mount.c
>> index 502d7e3433..bd75c9e704 100644
>> --- a/sysdeps/unix/sysv/linux/tst-mount.c
>> +++ b/sysdeps/unix/sysv/linux/tst-mount.c
>> @@ -103,7 +103,8 @@ subprocess (void)
>>  static int
>>  do_test (void)
>>  {
>> -  support_become_root ();
>> +  if (!support_become_root ())
>> +    FAIL_UNSUPPORTED("could not become root");
>>  
> 
> I think the usual way is to check if process can chroot:
> 
>   support_become_root ();
>   if (!support_can_chroot ())
>     return EXIT_UNSUPPORTED;
> 
> As done by other tests.

Agreed. We need this same fix for Fedora. I didn't catch this in my review.
 
>>    pid_t pid = xfork ();
>>    if (pid == 0)
> 


-- 
Cheers,
Carlos.