linux_dsm_epyc7002/arch/x86/boot
Thomas Garnier 021182e52f x86/mm: Enable KASLR for physical mapping memory regions
Add the physical mapping in the list of randomized memory regions.

The physical memory mapping holds most allocations from boot and heap
allocators. Knowing the base address and physical memory size, an attacker
can deduce the PDE virtual address for the vDSO memory page. This attack
was demonstrated at CanSecWest 2016, in the following presentation:

  "Getting Physical: Extreme Abuse of Intel Based Paged Systems":
  https://github.com/n3k/CansecWest2016_Getting_Physical_Extreme_Abuse_of_Intel_Based_Paging_Systems/blob/master/Presentation/CanSec2016_Presentation.pdf

(See second part of the presentation).

The exploits used against Linux worked successfully against 4.6+ but
fail with KASLR memory enabled:

  https://github.com/n3k/CansecWest2016_Getting_Physical_Extreme_Abuse_of_Intel_Based_Paging_Systems/tree/master/Demos/Linux/exploits

Similar research was done at Google leading to this patch proposal.

Variants exists to overwrite /proc or /sys objects ACLs leading to
elevation of privileges. These variants were tested against 4.6+.

The page offset used by the compressed kernel retains the static value
since it is not yet randomized during this boot stage.

Signed-off-by: Thomas Garnier <thgarnie@google.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Alexander Kuleshov <kuleshovmail@gmail.com>
Cc: Alexander Popov <alpopov@ptsecurity.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jan Beulich <JBeulich@suse.com>
Cc: Joerg Roedel <jroedel@suse.de>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Lv Zheng <lv.zheng@intel.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Toshi Kani <toshi.kani@hpe.com>
Cc: Xiao Guangrong <guangrong.xiao@linux.intel.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: kernel-hardening@lists.openwall.com
Cc: linux-doc@vger.kernel.org
Link: http://lkml.kernel.org/r/1466556426-32664-7-git-send-email-keescook@chromium.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-07-08 17:35:15 +02:00
..
compressed x86/mm: Enable KASLR for physical mapping memory regions 2016-07-08 17:35:15 +02:00
tools x86/boot: Remove unused 'is_big_kernel' variable 2016-02-16 09:16:58 +01:00
.gitignore
a20.c
apm.c
bioscall.S
bitops.h
boot.h x86/mm: Fix regression with huge pages on PAE 2015-12-04 09:14:27 +01:00
cmdline.c
code16gcc.h
copy.S
cpu.c
cpucheck.c
cpuflags.c
cpuflags.h x86/cpufeature: Carve out X86_FEATURE_* 2016-01-30 11:22:17 +01:00
ctype.h
early_serial_console.c x86/boot: Add missing file header comments 2016-05-10 10:12:03 +02:00
edd.c
header.S x86/boot: Calculate decompression size during boot not build 2016-04-29 11:03:29 +02:00
install.sh
main.c x86/boot: Obsolete the MCA sys_desc_table 2015-07-21 10:55:11 +02:00
Makefile x86, build: copy ldlinux.c32 to image.iso 2016-06-07 15:54:18 -07:00
memory.c
mkcpustr.c x86/cpufeature: Carve out X86_FEATURE_* 2016-01-30 11:22:17 +01:00
mtools.conf.in
pm.c
pmjump.S
printf.c
regs.c
setup.ld
string.c
string.h
tty.c
version.c
vesa.h
video-bios.c
video-mode.c x86/mm: Fix regression with huge pages on PAE 2015-12-04 09:14:27 +01:00
video-vesa.c
video-vga.c
video.c x86/mm: Fix regression with huge pages on PAE 2015-12-04 09:14:27 +01:00
video.h