linux/arch/x86/lib
Andy Lutomirski c482feefe1 x86/entry/64: Make cpu_entry_area.tss read-only
The TSS is a fairly juicy target for exploits, and, now that the TSS
is in the cpu_entry_area, it's no longer protected by kASLR.  Make it
read-only on x86_64.

On x86_32, it can't be RO because it's written by the CPU during task
switches, and we use a task gate for double faults.  I'd also be
nervous about errata if we tried to make it RO even on configurations
without double fault handling.

[ tglx: AMD confirmed that there is no problem on 64-bit with TSS RO.  So
  	it's probably safe to assume that it's a non issue, though Intel
  	might have been creative in that area. Still waiting for
  	confirmation. ]

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bpetkov@suse.de>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Laight <David.Laight@aculab.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Eduardo Valentin <eduval@amazon.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: aliguori@amazon.com
Cc: daniel.gruss@iaik.tugraz.at
Cc: hughd@google.com
Cc: keescook@google.com
Link: https://lkml.kernel.org/r/20171204150606.733700132@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-12-17 14:27:52 +01:00
..
.gitignore
atomic64_32.c
atomic64_386_32.S x86/debug: Remove perpetually broken, unmaintainable dwarf annotations 2015-06-02 07:57:48 +02:00
atomic64_cx8_32.S x86/debug: Remove perpetually broken, unmaintainable dwarf annotations 2015-06-02 07:57:48 +02:00
cache-smp.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
checksum_32.S x86: move exports to actual definitions 2016-08-07 23:47:15 -04:00
clear_page_64.S x86/asm: Optimize clear_page() 2017-03-07 08:28:00 +01:00
cmdline.c x86/boot: Add early cmdline parsing for options with arguments 2017-07-18 11:38:06 +02:00
cmpxchg8b_emu.S x86: move exports to actual definitions 2016-08-07 23:47:15 -04:00
cmpxchg16b_emu.S x86/debug: Remove perpetually broken, unmaintainable dwarf annotations 2015-06-02 07:57:48 +02:00
copy_page_64.S License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
copy_user_64.S x86/uaccess: Optimize copy_user_enhanced_fast_string() for short strings 2017-06-30 09:52:51 +02:00
cpu.c x86/lib: Audit and remove any unnecessary uses of module.h 2016-07-14 15:06:58 +02:00
csum-copy_64.S x86/asm: Don't use RBP as a temporary register in csum_partial_copy_generic() 2017-05-05 07:59:24 +02:00
csum-partial_64.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
csum-wrappers_64.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
delay.c x86/entry/64: Make cpu_entry_area.tss read-only 2017-12-17 14:27:52 +01:00
getuser.S License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
hweight.S License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
inat.c
insn.c x86/insn: Add AVX-512 support to the instruction decoder 2016-07-21 09:37:11 -03:00
iomap_copy_64.S x86/debug: Remove perpetually broken, unmaintainable dwarf annotations 2015-06-02 07:57:48 +02:00
kaslr.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
Makefile License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
memcpy_32.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
memcpy_64.S x86/mce: Fix copy/paste error in exception table entries 2017-03-22 08:43:25 +01:00
memmove_64.S License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
memset_64.S License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
misc.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
mmx_32.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
msr-reg-export.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
msr-reg.S License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
msr-smp.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
msr.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
putuser.S License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
rwsem.S locking/rwsem: Fix comment on register clobbering 2016-05-16 12:35:40 +02:00
string_32.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
strstr_32.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
usercopy_32.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
usercopy_64.c x86, dax, libnvdimm: remove wb_cache_pmem() indirection 2017-06-15 14:35:24 -07:00
usercopy.c x86: switch to RAW_COPY_USER 2017-03-29 12:06:28 -04:00
x86-opcode-map.txt x86/insn: perf tools: Add new ptwrite instruction 2017-06-27 11:58:04 -03:00