Re: [PULL 1/1] linux-user: Support futex_time64

[Alistair Francis]

On Tue, Nov 3, 2020 at 8:00 AM Laurent Vivier <laurent@vivier.eu> wrote:
>
> Le 03/11/2020 à 16:40, Alistair Francis a écrit :
> > On Mon, Nov 2, 2020 at 11:29 PM Laurent Vivier <laurent@vivier.eu> wrote:
> >>
> >> Le 02/11/2020 à 19:15, Peter Maydell a écrit :
> >>> On Mon, 30 Mar 2020 at 11:31, Laurent Vivier <laurent@vivier.eu> wrote:
> >>>>
> >>>> From: Alistair Francis <alistair.francis@wdc.com>
> >>>>
> >>>> Add support for host and target futex_time64. If futex_time64 exists on
> >>>> the host we try that first before falling back to the standard futex
> >>>> syscall.
> >>>
> >>> Hi; I dunno why Coverity's only just noticed this, but in
> >>> CID 1432339 it points out:
> >>>
> >>>> +#if defined(TARGET_NR_futex_time64)
> >>>> +static int do_futex_time64(target_ulong uaddr, int op, int val, 
> >>>> target_ulong timeout,
> >>>> +                           target_ulong uaddr2, int val3)
> >>>> +{
> >>>> +    struct timespec ts, *pts;
> >>>> +    int base_op;
> >>>> +
> >>>> +    /* ??? We assume FUTEX_* constants are the same on both host
> >>>> +       and target.  */
> >>>> +#ifdef FUTEX_CMD_MASK
> >>>> +    base_op = op & FUTEX_CMD_MASK;
> >>>> +#else
> >>>> +    base_op = op;
> >>>> +#endif
> >>>> +    switch (base_op) {
> >>>> +    case FUTEX_WAIT:
> >>>> +    case FUTEX_WAIT_BITSET:
> >>>> +        if (timeout) {
> >>>> +            pts = &ts;
> >>>> +            target_to_host_timespec64(pts, timeout);
> >>>
> >>> ...that here we call target_to_host_timespec64(), which can
> >>> fail with -TARGET_EFAULT, but (unlike all the other times we call
> >>> the function) we aren't checking its return value.
> >>> Is there missing error handling code here ?
> >>>
> >>
> >> I think the code is like that because this is a cut&paste of function
> >> do_futex() witl "s/timespec/timespec64/".
> >>
> >> And yes I think we should check for the return value.
> >> I'm going to fix that.
> >
> > Thanks! Let me know if you want me to do it and I can send a patch instead.
> >
>
> If you have time, please do.

Sending the patch now.

Alistair

>
> Thanks
> Laurent
>