[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <m13agf68a7.fsf@frodo.ebiederm.org>
Date: Mon, 22 Dec 2008 16:32:16 -0800
From: ebiederm@...ssion.com (Eric W. Biederman)
To: Oleg Nesterov <oleg@...hat.com>
Cc: Sukadev Bhattiprolu <sukadev@...ux.vnet.ibm.com>,
ebiederm@...ssion.com, roland@...hat.com, bastian@...di.eu.org,
daniel@...ac.com, xemul@...nvz.org, containers@...ts.osdl.org,
linux-kernel@...r.kernel.org, sukadev@...ibm.com
Subject: Re: [RFC][PATCH 4/6][v3] Define siginfo_from_ancestor_ns()
Oleg Nesterov <oleg@...hat.com> writes:
>> I was going through the ->si_pid assignments to try and fix them at
>> source (like the mqueue patch I sent last week).
>
> OK.
Note. When a signal goes to a process group (or similar) we can't fix
si_pid at the source. We have to fix it when only a single destination
process is known. It doesn't mean that fixing it at the source
is hopeless but...
>> The two cases that don't fit the model are sys_kill() and sys_tkill().
>> For that I was hoping we could use siginfo_from_user() again. i.e
>>
>> if (siginfo_from_user())
>> masquerade_si_pid()
>>
>> in the default: case of send_signal(). To be safe, masquerade_si_pid()
>> could do it only iff si_code is either SI_USER or SI_TKILL.
>>
>> IOW, with some tweaks, I am trying to see if we can use siginfo_from_user()
>> in place of the SIG_FROM_USER.
>
> sys_rt_sigqueueinfo().
>
> But, perhaps we can just ignore the problems with sigqueueinfo() (and
> document them).
Yes. I don't think si_pid is valid in that case anyway. It is the
kernel signals where si_pid is a reliable field that are important.
Eric
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists