metag/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.

Signed-off-by: Dave Martin <Dave.Martin@arm.com>
Acked-by: James Hogan <james.hogan@imgtec.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Dave Martin 2017-03-27 15:10:55 +01:00 committed by Linus Torvalds
parent 502585c755
commit a78ce80d2c

View File

@ -303,7 +303,7 @@ static int metag_tls_set(struct task_struct *target,
const void *kbuf, const void __user *ubuf)
{
int ret;
void __user *tls;
void __user *tls = target->thread.tls_ptr;
ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &tls, 0, -1);
if (ret)