[pulseaudio-discuss] [PATCH] pipe-sink, pipe-source: fix file permissions

[Georg Chini]

On 09.07.2018 14:40, Tanu Kaskinen wrote:
> On Sat, 2018-07-07 at 11:48 +0200, Georg Chini wrote:
>> On 04.07.2018 12:40, Tanu Kaskinen wrote:
>>> We recently changed the umask of the daemon from 022 to 077, which broke
>>> module-pipe-sink in the system mode, because nobody was allowed to read
>>> from the pipe.
>>>
>>> module-pipe-source in the system mode was probably always broken,
>>> because the old umask of 022 should prevent anyone from writing to the
>>> pipe.
>>>
>>> This patch uses chmod() after the file creation to set the permissions
>>> to 0666, which is what the fkfifo() call tried to set.
>>>
>>> Bug link: https://bugs.freedesktop.org/show_bug.cgi?id=107070
>>> ---
>> Should the permissions really be 666? Would not 660 be better,
>> so that there is at least some control who may access the pipe?
> If the mode were 660, the bug that was reported would not be fixed. In
> the system mode the owner and group are "pulse", so nobody would be
> able to access the pipe.
>
> I agree that it's questionable to give everyone access, but that's what
> we've always done (or at least we've always given read access, but the
> intention has been to give write access as well).


OK, then your patch is fine for me.

>
> If we want to tighten the permissions, that can be done in a separate
> patch.
> We could make the mode configurable and default to 600 in the
> user mode and 666 in the system mode. We could also make the group
> configurable with "pulse-access" as the default group, then we could
> default to 660 in the system mode.
>
> We could also remove write access in case of module-pipe-sink and read
> access in case of module-pipe-source.
>