Interesting error emitted by gparted

[jd1008]

On 10/21/2015 07:35 PM, Cameron Simpson wrote:
> 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.
>
OK.
Here is the output (much larger though):
https://fs10n4.sendspace.com/dl/3c9a124ef8adc2f92e3986ddd6f6f015/56283fe3277f93ee/oiuyue/strace_-f_gparted.out.bz2

I hope you can correlate it somehow to source code.

I used to use source code debuggers which made my life a lot eazier.