[PATCH weston v2] libweston-desktop: don't crash when getting the pid for X clients

[Quentin Glidic]

On 08/12/2016 09:21, Giulio Camuffo wrote:
> X client's don't have a wl_client associated with their
> weston_desktop_client, so make sure to not use it.
>
> Signed-off-by: Giulio Camuffo <giuliocamuffo at gmail.com>

Perfect:
Reviewed-by: Quentin Glidic <sardemff7+git at sardemff7.net>

Cheers,

> ---
>
> v2: use -1 as the pid unset value, and initialize the pid to 0 for xwayland
>     surfaces. This means the branch where we use the client is never reached
>     for xwayland, even if the pid is not set.
>
>  libweston-desktop/surface.c  | 8 +++++++-
>  libweston-desktop/xwayland.c | 2 ++
>  2 files changed, 9 insertions(+), 1 deletion(-)
>
> diff --git a/libweston-desktop/surface.c b/libweston-desktop/surface.c
> index 2205107..d3be936 100644
> --- a/libweston-desktop/surface.c
> +++ b/libweston-desktop/surface.c
> @@ -269,6 +269,8 @@ weston_desktop_surface_create(struct weston_desktop *desktop,
>  	wsurface->committed = weston_desktop_surface_committed;
>  	wsurface->committed_private = surface;
>
> +	surface->pid = -1;
> +
>  	surface->surface_commit_listener.notify =
>  		weston_desktop_surface_surface_committed;
>  	wl_signal_add(&surface->surface->commit_signal,
> @@ -590,7 +592,7 @@ weston_desktop_surface_get_pid(struct weston_desktop_surface *surface)
>  {
>  	pid_t pid;
>
> -	if (surface->pid != 0) {
> +	if (surface->pid != -1) {
>  		pid = surface->pid;
>  	} else {
>  		struct weston_desktop_client *client =
> @@ -598,6 +600,10 @@ weston_desktop_surface_get_pid(struct weston_desktop_surface *surface)
>  		struct wl_client *wl_client =
>  			weston_desktop_client_get_client(client);
>
> +		/* wl_client should always be valid, because only in the
> +		 * xwayland case it wouldn't be, but in that case we won't
> +		 * reach here, as the pid is initialized to 0. */
> +		assert(wl_client);
>  		wl_client_get_credentials(wl_client, &pid, NULL, NULL);
>  	}
>  	return pid;
> diff --git a/libweston-desktop/xwayland.c b/libweston-desktop/xwayland.c
> index c89248c..0741a4c 100644
> --- a/libweston-desktop/xwayland.c
> +++ b/libweston-desktop/xwayland.c
> @@ -241,6 +241,8 @@ create_surface(struct weston_desktop_xwayland *xwayland,
>  	wl_resource_add_destroy_listener(wsurface->resource,
>  					 &surface->resource_destroy_listener);
>
> +	weston_desktop_surface_set_pid(surface->surface, 0);
> +
>  	return surface;
>  }
>
>


-- 

Quentin “Sardem FF7” Glidic