Re: "core dump helper" runs always as root

[Reto Buerki <buerki@swiss-it.ch>]

> 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