[RFC patch 4/6] arm64: Use simpler API for random address requests

From: Jason Cooper
Date: Mon Jul 25 2016 - 23:05:35 EST


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.

Signed-off-by: Jason Cooper <jason@xxxxxxxxxxxxxx>
---
arch/arm64/kernel/process.c | 8 ++------
1 file changed, 2 insertions(+), 6 deletions(-)

diff --git a/arch/arm64/kernel/process.c b/arch/arm64/kernel/process.c
index 6cd2612236dc..11bf454baf86 100644
--- a/arch/arm64/kernel/process.c
+++ b/arch/arm64/kernel/process.c
@@ -374,12 +374,8 @@ unsigned long arch_align_stack(unsigned long sp)

unsigned long arch_randomize_brk(struct mm_struct *mm)
{
- unsigned long range_end = mm->brk;
-
if (is_compat_task())
- range_end += 0x02000000;
+ return randomize_addr(mm->brk, 0x02000000);
else
- range_end += 0x40000000;
-
- return randomize_range(mm->brk, range_end, 0) ? : mm->brk;
+ return randomize_addr(mm->brk, 0x40000000);
}
--
2.9.2