Interesting error emitted by gparted

[Cameron Simpson]

On 21Oct2015 18:39, jd1008 <jd1008 at gmail.com> wrote:
>On 10/21/2015 03:57 PM, Cameron Simpson wrote:
>>On 21Oct2015 13:21, jd1008 <jd1008 at gmail.com> wrote:
>>># gparted
>>>Failed to execute operation: Access denied
>>>======================
>>>libparted : 3.2
>>>======================
>>>
>>>I did not perform any operations, and no operations were pending.
>>>There are 3 drives: sda sdb sdc
>>>
>>>Selecting File->quit
>>>
>>>belches out
>>>Failed to execute operation: Access denied
>>>
>>>Can anyone shed some light on this?
>>
>>selinux?
>>
>>Does strace shed any light on what it was doing just before the error?
>>
>>Cheers,
>>Cameron Simpson <cs at zip.com.au>
>See strace output at
>https://www.sendspace.com/file/lo83pz

Hmm. It looks like this message comes from a subcommand that gparted invokes, 
or a subprocess before executing the subcommand.

See here:

  access("/bin/systemctl", R_OK)          = 0
  rt_sigprocmask(SIG_BLOCK, [INT CHLD], [], 8) = 0
  rt_sigprocmask(SIG_BLOCK, [CHLD], [INT CHLD], 8) = 0
  rt_sigprocmask(SIG_SETMASK, [INT CHLD], NULL, 8) = 0
  clone(child_stack=0, flags=CLONE_CHILD_CLEARTID|CLONE_CHILD_SETTID|SIGCHLD, child_tidptr=0x7ff209b239d0) = 12884
  rt_sigprocmask(SIG_SETMASK, [], NULL, 8) = 0
  rt_sigprocmask(SIG_BLOCK, [CHLD], [], 8) = 0
  rt_sigprocmask(SIG_SETMASK, [], NULL, 8) = 0
  rt_sigprocmask(SIG_BLOCK, [CHLD], [], 8) = 0
  rt_sigaction(SIGINT, {0x559e190c9290, [], SA_RESTORER, 0x7ff209192a50}, {SIG_DFL, [], SA_RESTORER, 0x7ff209192a50}, 8) = 0
  wait4(-1, Failed to execute operation: Access denied
  [{WIFEXITED(s) && WEXITSTATUS(s) == 1}], 0, NULL) = 12884

That "Failed to execute operation: Access denied" is not an error from a system 
call in the main process; instead if is embedded in the stderr output. The 
sequence above suggests that gparted is about to invoke the systemctl command, 
and perhaps that issues the error, or gparted issues the error in the cloned 
subprocess.

Please rerun strace with the "-f" option to follow forked processes. That 
should reveal more detail.

Cheers,
Cameron Simpson <cs at zip.com.au>