ARM: 8643/3: arm/ptrace: Preserve previous registers for short regset write
authorDave Martin <Dave.Martin@arm.com>
Wed, 18 Jan 2017 16:11:56 +0000 (17:11 +0100)
committerRussell King <rmk+kernel@armlinux.org.uk>
Mon, 30 Jan 2017 12:04:12 +0000 (12:04 +0000)
Ensure that if userspace supplies insufficient data to
PTRACE_SETREGSET to fill all the registers, the thread's old
registers are preserved.

Cc: <stable@vger.kernel.org> # 3.0.x-
Fixes: 5be6f62b0059 ("ARM: 6883/1: ptrace: Migrate to regsets framework")
Signed-off-by: Dave Martin <Dave.Martin@arm.com>
Acked-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
arch/arm/kernel/ptrace.c

index ce131ed5939d5ff86054afc3a14de7cb51225a79..ae738a6319f6a341c05a3c6a2dee2da30aa02a40 100644 (file)
@@ -600,7 +600,7 @@ static int gpr_set(struct task_struct *target,
                   const void *kbuf, const void __user *ubuf)
 {
        int ret;
-       struct pt_regs newregs;
+       struct pt_regs newregs = *task_pt_regs(target);
 
        ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
                                 &newregs,