From a672401c00f82e4e19704aff361d9bad18003714 Mon Sep 17 00:00:00 2001 From: Dave Martin Date: Wed, 18 Jan 2017 16:25:22 +0000 Subject: [PATCH] arm64/ptrace: Preserve previous registers for short regset write Ensure that if userspace supplies insufficient data to PTRACE_SETREGSET to fill all the registers, the thread's old registers are preserved. Cc: # 4.3.x- Fixes: 5d220ff9420f ("arm64: Better native ptrace support for compat tasks") Signed-off-by: Dave Martin Acked-by: Will Deacon Signed-off-by: Catalin Marinas --- arch/arm64/kernel/ptrace.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/arm64/kernel/ptrace.c b/arch/arm64/kernel/ptrace.c index ead36d5..91c4719 100644 --- a/arch/arm64/kernel/ptrace.c +++ b/arch/arm64/kernel/ptrace.c @@ -950,7 +950,7 @@ static int compat_tls_set(struct task_struct *target, const void __user *ubuf) { int ret; - compat_ulong_t tls; + compat_ulong_t tls = target->thread.tp_value; ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &tls, 0, -1); if (ret) -- 2.7.4