On 03/18, Jiri Olsa wrote:
>
> +SYSCALL_DEFINE0(uretprobe)
> +{
> + struct pt_regs *regs = task_pt_regs(current);
> + unsigned long sregs[3], err;
> +
> + /*
> + * We set rax and syscall itself changes rcx and r11, so the syscall
> + * trampoline saves their original values on stack. We need to read
> + * them and set original register values and fix the rsp pointer back.
> + */
> + err = copy_from_user((void *) &sregs, (void *) regs->sp, sizeof(sregs));
^^^^^^^^^^^^^^^^^
IIUC, it should be (void __user *)regs->sp to shut up the sparse checks.
The 1st "(void *)" typecast is not needed.
Correctness-wise looks good to me, FWIW
Reviewed-by: Oleg Nesterov <oleg@xxxxxxxxxx>
