Commit ac34ceaf authored Jul 06, 2017 by Daniel Micay Committed by Linus Torvalds Jul 06, 2017

mm/mmap.c: mark protection_map as __ro_after_init

The protection map is only modified by per-arch init code so it can be
protected from writes after the init code runs.

This change was extracted from PaX where it's part of KERNEXEC.

Link: http://lkml.kernel.org/r/20170510174441.26163-1-danielmicay@gmail.com


Signed-off-by: Daniel Micay <danielmicay@gmail.com>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent c4e1be9e

mm/mmap.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -94,7 +94,7 @@ static void unmap_region(struct mm_struct *mm,
		* w: (no) no
		* x: (yes) yes
		*/
		pgprot_t protection_map[16] = {
		pgprot_t protection_map[16] __ro_after_init = {
		__P000, __P001, __P010, __P011, __P100, __P101, __P110, __P111,
		__S000, __S001, __S010, __S011, __S100, __S101, __S110, __S111
		};