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/[email protected] Signed-off-by: Daniel Micay <[email protected]> Acked-by: Kees Cook <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
cail · Jul 6, 2017 · ac34cea · ac34cea
1 parent c4e1be9
commit ac34cea
Showing 1 changed file with 1 addition and 1 deletion.
diff --git a/mm/mmap.c b/mm/mmap.c
@@ -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
 };