Re: [PATCH] Fix siginfo._uid bug

[Geert Uytterhoeven <geert@linux-m68k.org>]

On Thu, Nov 19, 2009 at 20:47, Maxim Kuvyrkov <maxim@codesourcery.com> wrote:
> Geert Uytterhoeven wrote:
>> On Mon, Oct 26, 2009 at 15:21, Maxim Kuvyrkov <maxim@codesourcery.com>
>> wrote:
>>>
>>> Maxim Kuvyrkov wrote:
>>>>
>>>> Maxim Kuvyrkov wrote:
>>>>>
>>>>> Andreas Schwab wrote:
>
> ...
>>>>>
>>>>> Moving on to the generic version of siginfo.h will certainly fix the
>>>>> problem, otherwise, one needs to pad extra 2 bytes in _timer.
>>>>
>>>> While the discussion is pending, here is an updated version of the patch
>>>> that also patches up sigval.
>>>
>>> Ping?  Broken signal handling is a quite serious bug.
>>>
>>> Geert, which option of fixing would you prefer?
>>
>> Unfortunately I'm far from a signal expert...
>>
>> Fixing this breaks backwards compatibility, right?
>
> Not really.  Fixing this bug will only make applications to receive expected
> results in signal handlers they register.
>
>> So what are the consequences? Which applications are affected? Just
>> gdb? So we need a fixed gdb binary in Debian?
>
> While GDB is a heavy user of signals, it's not the only application that's
> affected.  GLIBC is affected for sure, as is anything that is using signals
> to the extent of checking UID of the process which sent the signal.
>
> The question is which solution should we adopt.  The patch I posted fixes
> all current problems with have on our hands.  Andreas suggested to move to
> the generic layout of `struct siginfo' which will make future problems less
> likely, but this approach may need additional investigation.

If moving to the generic layout decreases the probability of future problems,
it's the way to go.

Gr{oetje,eeting}s,

						Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
							    -- Linus Torvalds