Re: [Qemu-devel] [PATCH] linux-user: fix settime old value location

[Peter Maydell]

On 15 September 2016 at 15:52, Marc-André Lureau
<address@hidden> wrote:
> old_value is the 4th argument of timer_settime(), not the 2nd.
>
> Signed-off-by: Marc-André Lureau <address@hidden>
> ---
>  linux-user/syscall.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/linux-user/syscall.c b/linux-user/syscall.c
> index ca06943..345e971 100644
> --- a/linux-user/syscall.c
> +++ b/linux-user/syscall.c
> @@ -11679,7 +11679,7 @@ abi_long do_syscall(void *cpu_env, int num, abi_long 
> arg1,
>              target_to_host_itimerspec(&hspec_new, arg3);
>              ret = get_errno(
>                            timer_settime(htimer, arg2, &hspec_new, 
> &hspec_old));
> -            host_to_target_itimerspec(arg2, &hspec_old);
> +            host_to_target_itimerspec(arg4, &hspec_old);
>          }
>          break;
>      }

This is definitely a bug, but not the only one here.
host_to_target_itimerspec() and target_to_host_itimerspec() can both
return -TARGET_EFAULT, but we are ignoring their return values.
Also old_value may be NULL but we don't check for that.

thanks
-- PMM