linux_dsm_epyc7002/arch/x86
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
..
boot x86/mm: Enable KASLR for physical mapping memory regions 2016-07-08 17:35:15 +02:00
configs arch/defconfig: remove CONFIG_RESOURCE_COUNTERS 2016-05-23 17:04:14 -07:00
crypto Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2016-05-20 10:25:16 -07:00
entry x86/vdso: Add mremap hook to vm_special_mapping 2016-07-08 14:17:51 +02:00
events perf/x86/intel/uncore: Remove SBOX support for Broadwell server 2016-06-03 08:39:38 +02:00
ia32 mm: remove more IS_ERR_VALUE abuses 2016-05-27 15:57:31 -07:00
include x86/mm: Enable KASLR for physical mapping memory regions 2016-07-08 17:35:15 +02:00
kernel x86/mm: Enable KASLR for physical mapping memory regions 2016-07-08 17:35:15 +02:00
kvm KVM: nVMX: VMX instructions: fix segment checks when L1 is in long mode. 2016-06-27 15:30:44 +02:00
lguest x86/paravirt: Remove paravirt_enabled() 2016-04-22 10:29:07 +02:00
lib x86/mm: Refactor KASLR entropy functions 2016-07-08 17:33:45 +02:00
math-emu Merge branch 'x86-headers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-11-03 21:05:40 -08:00
mm x86/mm: Enable KASLR for physical mapping memory regions 2016-07-08 17:35:15 +02:00
net bpf, x86: add support for constant blinding 2016-05-16 13:49:32 -04:00
oprofile x86/cpufeature: Replace cpu_has_apic with boot_cpu_has() usage 2016-04-13 11:37:41 +02:00
pci xen: bug fixes for 4.7-rc0 2016-05-24 10:22:34 -07:00
platform x86/efi: get rid of superfluous __GFP_REPEAT 2016-06-24 17:23:52 -07:00
power x86/cpufeature: Remove cpu_has_pse 2016-03-31 13:35:10 +02:00
purgatory kbuild: delete unnecessary "@:" 2016-04-20 10:36:57 +02:00
ras x86/RAS: Add SMCA support to AMD Error Injector 2016-05-12 09:08:23 +02:00
realmode x86/mm: Separate variable for trampoline PGD 2016-07-08 17:33:46 +02:00
tools x86/KASLR: Clean up unused code from old 'run_size' and rename it to 'kernel_total_size' 2016-04-29 11:03:30 +02:00
um Merge branch 'for-linus-4.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml 2016-05-27 18:54:59 -07:00
video x86/video: Don't assume all FB devices are PCI devices 2016-03-15 11:08:26 +01:00
xen Merge branch 'akpm' (patches from Andrew) 2016-06-24 19:08:33 -07:00
.gitignore
Kbuild perf/x86: Move perf_event.c ............... => x86/events/core.c 2016-02-09 10:23:49 +01:00
Kconfig x86/mm: Implement ASLR for kernel memory regions 2016-07-08 17:33:46 +02:00
Kconfig.cpu x86/Kconfig/cpus: Fix/complete CPU type help texts 2015-10-21 11:12:56 +02:00
Kconfig.debug Merge branch 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2016-03-15 09:32:27 -07:00
Makefile x86/init: Rename EBDA code file 2016-04-22 10:29:07 +02:00
Makefile_32.cpu
Makefile.um