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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
Documentation clang-format: add configuration file 2018-04-11 10:28:35 -07:00
LICENSES LICENSES: Add MPL-1.1 license 2018-01-06 10:59:44 -07:00
arch exec: pass stack rlimit into mm layout functions 2018-04-11 10:28:37 -07:00
block for-4.17/block-20180402 2018-04-05 14:27:02 -07:00
certs certs/blacklist_nohashes.c: fix const confusion in certs blacklist 2018-02-21 15:35:43 -08:00
crypto MIPS changes for 4.17 2018-04-10 11:39:22 -07:00
drivers proc: add seq_put_decimal_ull_width to speed up /proc/pid/smaps 2018-04-11 10:28:33 -07:00
firmware kbuild: remove all dummy assignments to obj- 2017-11-18 11:46:06 +09:00
fs exec: pass stack rlimit into mm layout functions 2018-04-11 10:28:37 -07:00
include exec: pass stack rlimit into mm layout functions 2018-04-11 10:28:37 -07:00
init seq_file: allocate seq_file from kmem_cache 2018-04-11 10:28:36 -07:00
ipc proc: move /proc/sysvipc creation to where it belongs 2018-04-11 10:28:33 -07:00
kernel uts: create "struct uts_namespace" from kmem_cache 2018-04-11 10:28:35 -07:00
lib lib/list_debug.c: print unmangled addresses 2018-04-11 10:28:35 -07:00
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 2018-04-09 17:04:10 -07:00
samples VFIO updates for v4.17-rc1 2018-04-06 19:44:27 -07:00
scripts checkpatch: whinge about bool bitfields 2018-04-11 10:28:36 -07:00
security New features: 2018-04-10 11:27:30 -07:00
sound sound fixes for 4.17-rc1 2018-04-10 10:16:04 -07:00
tools proc: selftests: test /proc/uptime 2018-04-11 10:28:34 -07:00
usr kbuild: rename built-in.o to built-in.a 2018-03-26 02:01:19 +09:00
virt KVM/ARM updates for v4.17 2018-03-28 16:09:09 +02:00
.clang-format clang-format: add configuration file 2018-04-11 10:28:35 -07:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.get_maintainer.ignore
.gitattributes .gitattributes: set git diff driver for C source code files 2016-10-07 18:46:30 -07:00
.gitignore clang-format: add configuration file 2018-04-11 10:28:35 -07:00
.mailmap Merge candidates for 4.17 merge window 2018-04-06 17:35:43 -07:00
COPYING COPYING: use the new text with points to the license files 2018-03-23 12:41:45 -06:00
CREDITS MAINTAINERS/CREDITS: Drop METAG ARCHITECTURE 2018-03-05 16:34:24 +00:00
Kbuild Kbuild updates for v4.15 2017-11-17 17:45:29 -08:00
Kconfig License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
MAINTAINERS MAINTAINERS: update email address for Alexandre Bounine 2018-04-11 10:28:35 -07:00
Makefile Kconfig updates for v4.17 2018-04-03 16:28:01 -07:00
README Docs: Added a pointer to the formatted docs to README 2018-03-21 09:02:53 -06:00

README

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
See Documentation/00-INDEX for a list of what is contained in each file.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.