[PATCH 3.16 237/370] arm64/ptrace: Avoid uninitialised struct padding in fpr_set()

From: Ben Hutchings
Date: Fri Mar 10 2017 - 07:42:44 EST


3.16.42-rc1 review patch. If anyone has any objections, please let me know.

------------------

From: Dave Martin <Dave.Martin@xxxxxxx>

commit aeb1f39d814b2e21e5e5706a48834bfd553d0059 upstream.

This patch adds an explicit __reserved[] field to user_fpsimd_state
to replace what was previously unnamed padding.

This ensures that data in this region are propagated across
assignment rather than being left possibly uninitialised at the
destination.

Fixes: 60ffc30d5652 ("arm64: Exception handling")
Signed-off-by: Dave Martin <Dave.Martin@xxxxxxx>
Acked-by: Will Deacon <Will.Deacon@xxxxxxx>
Signed-off-by: Catalin Marinas <catalin.marinas@xxxxxxx>
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
arch/arm64/include/uapi/asm/ptrace.h | 1 +
1 file changed, 1 insertion(+)

--- a/arch/arm64/include/uapi/asm/ptrace.h
+++ b/arch/arm64/include/uapi/asm/ptrace.h
@@ -75,6 +75,7 @@ struct user_fpsimd_state {
__uint128_t vregs[32];
__u32 fpsr;
__u32 fpcr;
+ __u32 __reserved[2];
};

struct user_hwdebug_state {