Re: [XEN PATCH][for-4.19] domain: add ASSERT to help static analysis tools

[Andrew Cooper <andrew.cooper3@citrix.com>]

On 03/11/2023 5:58 pm, Nicola Vetrini wrote:
> Static analysis tools may detect a possible null
> pointer dereference at line 760 (the memcpy call)
> of xen/common/domain.c. This ASSERT helps them in
> detecting that such a condition is not possible
> and also provides a basic sanity check.
>
> Signed-off-by: Nicola Vetrini <nicola.vetrini@bugseng.com>
> ---
> The check may be later improved by proper error checking
> instead of relying on the semantics explained here:
> https://lore.kernel.org/xen-devel/61f04d4b-34d9-4fd1-a989-56b042b4f3d8@citrix.com/
>
> This addresses the caution reported by ECLAIR for MISRA C:2012 D4.11
> ---
>  xen/common/domain.c | 2 ++
>  1 file changed, 2 insertions(+)
>
> diff --git a/xen/common/domain.c b/xen/common/domain.c
> index 8f9ab01c0cb7..9378c0417645 100644
> --- a/xen/common/domain.c
> +++ b/xen/common/domain.c
> @@ -700,6 +700,8 @@ struct domain *domain_create(domid_t domid,
>  
>      if ( !is_idle_domain(d) )
>      {
> +        ASSERT(config);
> +
>          watchdog_domain_init(d);
>          init_status |= INIT_watchdog;
>  

I have an idea that might resolve this differently and in an easier way.

Would you be happy waiting for a couple of days for me to experiment? 
Absolutely no guarantees of it turning into a workable solution.

~Andrew