+ arm64-use-simpler-api-for-random-address-requests.patch added to -mm tree

[akpm@linux-foundation.org]

The patch titled
     Subject: arm64: use simpler API for random address requests
has been added to the -mm tree.  Its filename is
     arm64-use-simpler-api-for-random-address-requests.patch

This patch should soon appear at
    http://ozlabs.org/~akpm/mmots/broken-out/arm64-use-simpler-api-for-random-address-requests.patch
and later at
    http://ozlabs.org/~akpm/mmotm/broken-out/arm64-use-simpler-api-for-random-address-requests.patch

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------------------------------------------------------
From: Jason Cooper <jason@lakedaemon.net>
Subject: arm64: use simpler API for random address requests

Currently, all callers to randomize_range() set the length to 0 and
calculate end by adding a constant to the start address.  We can simplify
the API to remove a bunch of needless checks and variables.

Use the new randomize_addr(start, range) call to set the requested
address.

Link: http://lkml.kernel.org/r/20160803233913.32511-5-jason@lakedaemon.net
Signed-off-by: Jason Cooper <jason@lakedaemon.net>
Acked-by: Will Deacon <will.deacon@arm.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: "Russell King - ARM Linux" <linux@arm.linux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 arch/arm64/kernel/process.c |    8 ++------
 1 file changed, 2 insertions(+), 6 deletions(-)

diff -puN arch/arm64/kernel/process.c~arm64-use-simpler-api-for-random-address-requests arch/arm64/kernel/process.c
--- a/arch/arm64/kernel/process.c~arm64-use-simpler-api-for-random-address-requests
+++ a/arch/arm64/kernel/process.c
@@ -374,12 +374,8 @@ unsigned long arch_align_stack(unsigned
 
 unsigned long arch_randomize_brk(struct mm_struct *mm)
 {
-	unsigned long range_end = mm->brk;
-
 	if (is_compat_task())
-		range_end += 0x02000000;
+		return randomize_page(mm->brk, 0x02000000);
 	else
-		range_end += 0x40000000;