From ac34ceaf1cdb34e8c34c0873ee562e9df6087cbc Mon Sep 17 00:00:00 2001
From: Daniel Micay <danielmicay@gmail.com>
Date: Thu, 6 Jul 2017 15:36:47 -0700
Subject: [PATCH] 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>
---
mm/mmap.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/mm/mmap.c b/mm/mmap.c
index a5e3dcd75e79f..5a0ba9788cdda 100644
--- 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
};
--
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