[igt-dev] [PATCH i-g-t] lib/ioctl_wrappers: Assert that prime_handle_to_fd returns a valid fd

[Chris Wilson]

Quoting Petri Latvala (2019-03-12 11:21:14)
> If the ioctl is successful, the returned fd should be valid. Check
> that it is, thus also helping static analysis in almost 70 call sites.
> 
> Signed-off-by: Petri Latvala <petri.latvala at intel.com>
> ---
>  lib/ioctl_wrappers.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/lib/ioctl_wrappers.c b/lib/ioctl_wrappers.c
> index 39920f87..31969e77 100644
> --- a/lib/ioctl_wrappers.c
> +++ b/lib/ioctl_wrappers.c
> @@ -1332,6 +1332,7 @@ int prime_handle_to_fd(int fd, uint32_t handle)
>         args.fd = -1;
>  
>         do_ioctl(fd, DRM_IOCTL_PRIME_HANDLE_TO_FD, &args);
> +       igt_assert_fd(args.fd);

Why? Why would we be using a static analysis tool that complains about
feeding invalid data to the kernel, because that is exactly the goal of
igt.
-Chris