[PATCH] x86/mm: Fix personality(ADDR_NO_RANDOMIZE)

[Kirill A. Shutemov]

In v4.12, during rework of infrastructure around mmap_base, disable-ASLR
personality flag got accidentally broken.

Let's make it work again.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
Fixes: 1b028f784e8c ("x86/mm: Introduce mmap_compat_base() for 32-bit mmap()")
Cc: stable <stable@xxxxxxxxxxxxxxx> [4.12+]
---
 arch/x86/mm/mmap.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/arch/x86/mm/mmap.c b/arch/x86/mm/mmap.c
index 229d04a83f85..779bdbe5e424 100644
--- a/arch/x86/mm/mmap.c
+++ b/arch/x86/mm/mmap.c
@@ -127,6 +127,8 @@ static unsigned long mmap_legacy_base(unsigned long rnd,
 static void arch_pick_mmap_base(unsigned long *base, unsigned long *legacy_base,
 		unsigned long random_factor, unsigned long task_size)
 {
+	if (!(current->flags & PF_RANDOMIZE))
+		random_factor = 0;
 	*legacy_base = mmap_legacy_base(random_factor, task_size);
 	if (mmap_is_legacy())
 		*base = *legacy_base;
-- 
2.14.1