exec: make do_coredump() more resilient to recursive crashes
authorNeil Horman <nhorman@tuxdriver.com>
Wed, 23 Sep 2009 22:56:54 +0000 (15:56 -0700)
committerLinus Torvalds <torvalds@linux-foundation.org>
Thu, 24 Sep 2009 14:21:00 +0000 (07:21 -0700)
commit725eae32df7754044809973034429a47e6035158
tree96a66c65a085940a19374ee02c26fb8f1931a6be
parentae6d2ed7bb3877ff35b9569402025f40ea2e1803
exec: make do_coredump() more resilient to recursive crashes

Change how we detect recursive dumps.

Currently we have a mechanism by which we try to compare pathnames of the
crashing process to the core_pattern path.  This is broken for a dozen
reasons, and just doesn't work in any sort of robust way.

I'm replacing it with the use of a 0 RLIMIT_CORE value.  Since helper apps
set RLIMIT_CORE to zero, we don't write out core files for any process
with that particular limit set.  It the core_pattern is a pipe, any
non-zero limit is translated to RLIM_INFINITY.

This allows complete dumps to be captured, but prevents infinite recursion
in the event that the core_pattern process itself crashes.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
Reported-by: Earl Chew <earl_chew@agilent.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
fs/exec.c