linux/arch/powerpc
Kees Cook 8f2af155b5 exec: pass stack rlimit into mm layout functions
Patch series "exec: Pin stack limit during exec".

Attempts to solve problems with the stack limit changing during exec
continue to be frustrated[1][2].  In addition to the specific issues
around the Stack Clash family of flaws, Andy Lutomirski pointed out[3]
other places during exec where the stack limit is used and is assumed to
be unchanging.  Given the many places it gets used and the fact that it
can be manipulated/raced via setrlimit() and prlimit(), I think the only
way to handle this is to move away from the "current" view of the stack
limit and instead attach it to the bprm, and plumb this down into the
functions that need to know the stack limits.  This series implements
the approach.

[1] 04e35f4495 ("exec: avoid RLIMIT_STACK races with prlimit()")
[2] 779f4e1c6c ("Revert "exec: avoid RLIMIT_STACK races with prlimit()"")
[3] to security@kernel.org, "Subject: existing rlimit races?"

This patch (of 3):

Since it is possible that the stack rlimit can change externally during
exec (either via another thread calling setrlimit() or another process
calling prlimit()), provide a way to pass the rlimit down into the
per-architecture mm layout functions so that the rlimit can stay in the
bprm structure instead of sitting in the signal structure until exec is
finalized.

Link: http://lkml.kernel.org/r/1518638796-20819-2-git-send-email-keescook@chromium.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Ben Hutchings <ben@decadent.org.uk>
Cc: Willy Tarreau <w@1wt.eu>
Cc: Hugh Dickins <hughd@google.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: "Jason A. Donenfeld" <Jason@zx2c4.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Laura Abbott <labbott@redhat.com>
Cc: Greg KH <greg@kroah.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Ben Hutchings <ben.hutchings@codethink.co.uk>
Cc: Brad Spengler <spender@grsecurity.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-11 10:28:37 -07:00
..
boot powerpc updates for 4.17 2018-04-07 12:08:19 -07:00
configs scsi: remove the fdomain and fdomain_cs drivers 2018-03-19 22:54:47 -04:00
crypto crypto: hash - annotate algorithms taking optional key 2018-01-12 23:03:35 +11:00
include ARM: 2018-04-09 11:42:31 -07:00
kernel powerpc updates for 4.17 2018-04-07 12:08:19 -07:00
kvm ARM: 2018-04-09 11:42:31 -07:00
lib powerpc/64s: Set assembler machine type to POWER4 2018-04-01 00:47:49 +11:00
math-emu License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
mm exec: pass stack rlimit into mm layout functions 2018-04-11 10:28:37 -07:00
net Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-03-05 11:29:24 -08:00
oprofile powerpc: Use sizeof(*foo) rather than sizeof(struct foo) 2018-03-20 16:47:53 +11:00
perf powerpc updates for 4.17 2018-04-07 12:08:19 -07:00
platforms libnvdimm for 4.17 2018-04-10 10:25:57 -07:00
purgatory License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
sysdev powerpc updates for 4.17 2018-04-07 12:08:19 -07:00
tools License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
xmon Merge branch 'topic/paca' into next 2018-03-31 09:09:36 +11:00
Kconfig Merge branch 'linus' into sched/urgent, to resolve conflicts 2018-02-06 21:12:31 +01:00
Kconfig.debug powerpc: Add new kconfig CONFIG_PPC_IRQ_SOFT_MASK_DEBUG 2018-01-19 22:37:03 +11:00
Makefile powerpc/64s: Add POWER9 CPU type selection 2018-04-01 22:15:32 +10:00
Makefile.postlink License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00