linux/arch/x86/mm
Baoquan He a46f60d760 x86/mm/KASLR: Exclude EFI region from KASLR VA space randomization
Currently KASLR is enabled on three regions: the direct mapping of physical
memory, vamlloc and vmemmap. However the EFI region is also mistakenly
included for VA space randomization because of misusing EFI_VA_START macro
and assuming EFI_VA_START < EFI_VA_END.

(This breaks kexec and possibly other things that rely on stable addresses.)

The EFI region is reserved for EFI runtime services virtual mapping which
should not be included in KASLR ranges. In Documentation/x86/x86_64/mm.txt,
we can see:

  ffffffef00000000 - fffffffeffffffff (=64 GB) EFI region mapping space

EFI uses the space from -4G to -64G thus EFI_VA_START > EFI_VA_END,
Here EFI_VA_START = -4G, and EFI_VA_END = -64G.

Changing EFI_VA_START to EFI_VA_END in mm/kaslr.c fixes this problem.

Signed-off-by: Baoquan He <bhe@redhat.com>
Reviewed-by: Bhupesh Sharma <bhsharma@redhat.com>
Acked-by: Dave Young <dyoung@redhat.com>
Acked-by: Thomas Garnier <thgarnie@google.com>
Cc: <stable@vger.kernel.org> #4.8+
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/1490331592-31860-1-git-send-email-bhe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-24 09:04:27 +01:00
..
kmemcheck x86/mm: Audit and remove any unnecessary uses of module.h 2016-07-14 13:04:20 +02:00
amdtopology.c x86/mm/numa: Open code function early_get_boot_cpu_id() 2016-08-15 08:51:54 +02:00
debug_pagetables.c x86/mm/ptdump: Make (debugfs)/kernel_page_tables read-only 2015-12-04 12:55:01 +01:00
dump_pagetables.c x86/mm/ptdump: Add address marker for KASAN shadow region 2017-02-16 19:53:25 +01:00
extable.c sched/headers: Prepare for new header dependencies before moving code to <linux/sched/debug.h> 2017-03-02 08:42:34 +01:00
fault.c sched/headers: Prepare for new header dependencies before moving code to <linux/sched/task_stack.h> 2017-03-02 08:42:36 +01:00
gup.c x86, mm: unify exit paths in gup_pte_range() 2017-03-09 17:01:09 -08:00
highmem_32.c x86/mm: Audit and remove any unnecessary uses of module.h 2016-07-14 13:04:20 +02:00
hugetlbpage.c sched/headers: Prepare for new header dependencies before moving more code to <linux/sched/mm.h> 2017-03-02 08:42:30 +01:00
ident_map.c x86/power/64: Always create temporary identity mapping correctly 2016-08-08 22:04:30 +02:00
init_32.c mm: add arch-independent testcases for RODATA 2017-02-27 18:43:48 -08:00
init_64.c mm: add arch-independent testcases for RODATA 2017-02-27 18:43:48 -08:00
init.c x86/e820: Use much less memory for e820/e820_saved, save up to 120k 2016-09-21 15:02:12 +02:00
iomap_32.c x86/mm: Audit and remove any unnecessary uses of module.h 2016-07-14 13:04:20 +02:00
ioremap.c x86/mm: Audit and remove any unnecessary uses of module.h 2016-07-14 13:04:20 +02:00
kasan_init_64.c x86/kasan: Fix boot with KASAN=y and PROFILE_ANNOTATED_BRANCHES=y 2017-03-14 00:00:55 +01:00
kaslr.c x86/mm/KASLR: Exclude EFI region from KASLR VA space randomization 2017-03-24 09:04:27 +01:00
kmmio.c x86/mm: Audit and remove any unnecessary uses of module.h 2016-07-14 13:04:20 +02:00
Makefile x86/mm: Implement ASLR for kernel memory regions 2016-07-08 17:33:46 +02:00
mm_internal.h x86: Enable PAT to use cache mode translation tables 2014-11-16 11:04:26 +01:00
mmap.c sched/headers: Prepare for new header dependencies before moving more code to <linux/sched/mm.h> 2017-03-02 08:42:30 +01:00
mmio-mod.c x86/mm: Audit and remove any unnecessary uses of module.h 2016-07-14 13:04:20 +02:00
mpx.c x86/mpx: Make unnecessarily global function static 2017-03-16 09:17:05 +01:00
numa_32.c x86/mm: Audit and remove any unnecessary uses of module.h 2016-07-14 13:04:20 +02:00
numa_64.c x86, mm: kill numa_free_all_bootmem() 2012-11-17 11:59:47 -08:00
numa_emulation.c x86: delete __cpuinit usage from all x86 files 2013-07-14 19:36:56 -04:00
numa_internal.h x86-32, mm: Rip out x86_32 NUMA remapping code 2013-01-31 14:12:30 -08:00
numa.c ACPI/NUMA: Do not map pxm to node when NUMA is turned off 2016-12-15 11:32:32 +01:00
pageattr-test.c x86/mm/pat: Make mm/pageattr[-test].c explicitly non-modular 2015-08-25 09:48:38 +02:00
pageattr.c x86/mm/cpa: Avoid wbinvd() for PREEMPT 2017-01-30 15:33:52 +01:00
pat_internal.h x86/mm/pat: Convert to pr_*() usage 2015-05-27 14:40:59 +02:00
pat_rbtree.c x86/mm/pat: Use rb_entry() 2017-02-04 17:18:00 +01:00
pat.c x86/pat, mm: Make track_pfn_insert() return void 2016-11-09 21:36:07 +01:00
pf_in.c x86/mm: Audit and remove any unnecessary uses of module.h 2016-07-14 13:04:20 +02:00
pf_in.h
pgtable_32.c Merge branch 'x86-headers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2016-08-01 14:23:42 -04:00
pgtable.c mm, x86: add support for PUD-sized transparent hugepages 2017-02-24 17:46:54 -08:00
physaddr.c x86/mm: Audit and remove any unnecessary uses of module.h 2016-07-14 13:04:20 +02:00
physaddr.h
pkeys.c x86/fpu: Finish excising 'eagerfpu' 2016-10-18 09:56:03 +02:00
setup_nx.c Revert "x86/mm/32: Set NX in __supported_pte_mask before enabling paging" 2016-04-26 19:52:57 +02:00
srat.c Merge branch 'x86-headers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2016-08-01 14:23:42 -04:00
testmmiotrace.c x86, kmmio/mmiotrace: Fix double free of kmmio_fault_pages 2010-06-18 11:30:09 +02:00
tlb.c x86/mm/64: Enable vmapped stacks (CONFIG_HAVE_ARCH_VMAP_STACK=y) 2016-08-24 12:11:42 +02:00