From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Dave Martin , Will Deacon , Catalin Marinas Subject: [PATCH 4.4 30/42] arm64/ptrace: Preserve previous registers for short regset write Date: Tue, 24 Jan 2017 08:55:40 +0100 Message-Id: <20170124075510.562629203@linuxfoundation.org> In-Reply-To: <20170124075509.299412838@linuxfoundation.org> References: <20170124075509.299412838@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Dave Martin commit 9a17b876b573441bfb3387ad55d98bf7184daf9d upstream. Ensure that if userspace supplies insufficient data to PTRACE_SETREGSET to fill all the registers, the thread's old registers are preserved. Fixes: 478fcb2cdb23 ("arm64: Debugging support") Signed-off-by: Dave Martin Acked-by: Will Deacon Signed-off-by: Catalin Marinas Signed-off-by: Greg Kroah-Hartman --- arch/arm64/kernel/ptrace.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) --- a/arch/arm64/kernel/ptrace.c +++ b/arch/arm64/kernel/ptrace.c @@ -495,7 +495,7 @@ static int gpr_set(struct task_struct *t const void *kbuf, const void __user *ubuf) { int ret; - struct user_pt_regs newregs; + struct user_pt_regs newregs = task_pt_regs(target)->user_regs; ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &newregs, 0, -1); if (ret) @@ -525,7 +525,8 @@ static int fpr_set(struct task_struct *t const void *kbuf, const void __user *ubuf) { int ret; - struct user_fpsimd_state newstate; + struct user_fpsimd_state newstate = + target->thread.fpsimd_state.user_fpsimd; ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &newstate, 0, -1); if (ret) @@ -549,7 +550,7 @@ static int tls_set(struct task_struct *t const void *kbuf, const void __user *ubuf) { int ret; - unsigned long tls; + unsigned long tls = target->thread.tp_value; ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &tls, 0, -1); if (ret)