linux/arch
Kees Cook fbbc400f39 arm: factor out mmap ASLR into mmap_rnd
To address the "offset2lib" ASLR weakness[1], this separates ET_DYN ASLR
from mmap ASLR, as already done on s390.  The architectures that are
already randomizing mmap (arm, arm64, mips, powerpc, s390, and x86), have
their various forms of arch_mmap_rnd() made available via the new
CONFIG_ARCH_HAS_ELF_RANDOMIZE.  For these architectures,
arch_randomize_brk() is collapsed as well.

This is an alternative to the solutions in:
https://lkml.org/lkml/2015/2/23/442

I've been able to test x86 and arm, and the buildbot (so far) seems happy
with building the rest.

[1] http://cybersecurity.upv.es/attacks/offset2lib/offset2lib.html

This patch (of 10):

In preparation for splitting out ET_DYN ASLR, this moves the ASLR
calculations for mmap on ARM into a separate routine, similar to x86.
This also removes the redundant check of personality (PF_RANDOMIZE is
already set before calling arch_pick_mmap_layout).

Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Hector Marco-Gisbert <hecmargi@upv.es>
Cc: Russell King <linux@arm.linux.org.uk>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: "David A. Long" <dave.long@linaro.org>
Cc: Andrey Ryabinin <a.ryabinin@samsung.com>
Cc: Arun Chandran <achandran@mvista.com>
Cc: Yann Droneaud <ydroneaud@opteya.com>
Cc: Min-Hua Chen <orca.chen@gmail.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Alex Smith <alex@alex-smith.me.uk>
Cc: Markos Chandras <markos.chandras@imgtec.com>
Cc: Vineeth Vijayan <vvijayan@mvista.com>
Cc: Jeff Bailey <jeffbailey@google.com>
Cc: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Cc: Ben Hutchings <ben@decadent.org.uk>
Cc: Behan Webster <behanw@converseincode.com>
Cc: Ismael Ripoll <iripoll@upv.es>
Cc: Jan-Simon Mller <dl9pf@gmx.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-14 16:49:05 -07:00
..
alpha alpha: expose number of page table levels on Kconfig level 2015-04-14 16:49:01 -07:00
arc ARC: signal handling robustify 2015-03-26 11:19:36 +05:30
arm arm: factor out mmap ASLR into mmap_rnd 2015-04-14 16:49:05 -07:00
arm64 arm64: expose number of page table levels on Kconfig level 2015-04-14 16:49:01 -07:00
avr32 avr32: fix integer overflow in ELF_ET_DYN_BASE 2015-04-13 18:48:55 +02:00
blackfin Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input 2015-02-21 12:59:04 -08:00
c6x arch/c6x/include/asm/pgtable.h: define dummy pgprot_writecombine for !MMU 2015-03-12 18:46:08 -07:00
cris CRIS changes for 3.20 2015-02-15 18:02:02 -08:00
frv Merge branches 'pci/enumeration' and 'pci/virtualization' into next 2015-03-23 17:17:34 -05:00
hexagon all arches, signal: move restart_block to struct task_struct 2015-02-12 18:54:12 -08:00
ia64 ia64: expose number of page table levels on Kconfig level 2015-04-14 16:49:02 -07:00
m32r mm: add missing __PAGETABLE_{PUD,PMD}_FOLDED defines 2015-02-28 09:57:51 -08:00
m68k m68k: mark PMD folded and expose number of page table levels 2015-04-14 16:49:02 -07:00
metag metag: Fix ioremap_wc/ioremap_cached build errors 2015-03-23 12:32:37 +00:00
microblaze Merge branches 'pci/enumeration' and 'pci/virtualization' into next 2015-03-23 17:17:34 -05:00
mips mips: expose number of page table levels on Kconfig level 2015-04-14 16:49:02 -07:00
mn10300 Merge branches 'pci/enumeration' and 'pci/virtualization' into next 2015-03-23 17:17:34 -05:00
nios2 nios2: fix cache coherency issue when debug with gdb 2015-04-10 11:10:08 +08:00
openrisc asm-generic: uaccess.h cleanup 2015-02-18 10:02:24 -08:00
parisc parisc: expose number of page table levels on Kconfig level 2015-04-14 16:49:02 -07:00
powerpc powerpc: expose number of page table levels on Kconfig level 2015-04-14 16:49:02 -07:00
s390 s390: expose number of page table levels 2015-04-14 16:49:02 -07:00
score all arches, signal: move restart_block to struct task_struct 2015-02-12 18:54:12 -08:00
sh sh: expose number of page table levels 2015-04-14 16:49:02 -07:00
sparc sparc: clarify __GFP_NOFAIL allocation 2015-04-14 16:49:04 -07:00
tile tile: expose number of page table levels 2015-04-14 16:49:02 -07:00
um um: expose number of page table levels 2015-04-14 16:49:02 -07:00
unicore32 PCI: Assign resources before drivers claim devices (pci_scan_bus()) 2015-03-12 15:04:01 -05:00
x86 x86, mm: support huge KVA mappings on x86 2015-04-14 16:49:04 -07:00
xtensa PCI: Assign resources before drivers claim devices (pci_scan_root_bus()) 2015-03-19 10:17:13 -05:00
.gitignore
Kconfig lib/ioremap.c: add huge I/O map capability interfaces 2015-04-14 16:49:04 -07:00