Message-ID: <48807821.8050504@swiss-it.ch>
Date: Fri, 18 Jul 2008 13:01:53 +0200
From: Reto Buerki <buerki@swiss-it.ch>
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To: linux-kernel@vger.kernel.org
Subject: Re: "core dump helper" runs always as root
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> If we run the usermode helper with the privileges of the dying process, what do 
> we do about rlimit enforcement?  They don't have a PAM environment, so either 
> they get the default rlimits, or we have to make them inherit their limits from 
> the dying process.  This is very problematic if the process died due to 
> exceeding an rlimit.

I'm not sure if I understand your objection correctly, but I thought
RLIMIT_CORE is ignored when using piped syntax with core_pattern.

At least this is how I interpret the code and the corresponding comment
in do_coredump() (fs/exec.c). The comment explicitly states that there's
no need to check RLIMIT_CORE value because file size limits and
permissions apply as they do with any other process.

There are also no further rlimit checks in usermode helper functions, at
least I could not find any ...

- reto


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