On 27 September 2018 at 08:12, Gerd Hoffmann <kra...@redhat.com> wrote:
> When processing monitor config from guest store head0 width and height
> for single-head configurations. Use these when creating the
> DisplaySurface in the local renderer.
>
> This fixes a rendering issue with wayland. Wayland rounds up the
> framebuffer width and height to a multiple of 64, so with odd
> resolutions (800x600 for example) the framebuffer is larger than the
> actual screen. The monitor config has the actual screen size though.
>
> This fixes guest display for anything using the local renderer
> (non-spice UI, screendump monitor command).
>
> Signed-off-by: Gerd Hoffmann <kra...@redhat.com>
> Reviewed-by: Marc-André Lureau <marcandre.lur...@redhat.com>
> Message-id: 20180919103057.9666-1-kra...@redhat.com
> diff --git a/hw/display/qxl.c b/hw/display/qxl.c
> index 8e9135d9c6..747986478f 100644
> --- a/hw/display/qxl.c
> +++ b/hw/display/qxl.c
> @@ -259,6 +259,8 @@ static void qxl_spice_destroy_surfaces(PCIQXLDevice *qxl,
> qxl_async_io async)
>
> static void qxl_spice_monitors_config_async(PCIQXLDevice *qxl, int replay)
> {
> + QXLMonitorsConfig *cfg;
> +
> trace_qxl_spice_monitors_config(qxl->id);
> if (replay) {
> /*
> @@ -286,6 +288,16 @@ static void qxl_spice_monitors_config_async(PCIQXLDevice
> *qxl, int replay)
> (uintptr_t)qxl_cookie_new(QXL_COOKIE_TYPE_IO,
> QXL_IO_MONITORS_CONFIG_ASYNC));
> }
> +
> + cfg = qxl_phys2virt(qxl, qxl->guest_monitors_config,
> MEMSLOT_GROUP_GUEST);
> + if (cfg->count == 1) {
> + qxl->guest_primary.resized = 1;
> + qxl->guest_head0_width = cfg->heads[0].width;
> + qxl->guest_head0_height = cfg->heads[0].height;
> + } else {
> + qxl->guest_head0_width = 0;
> + qxl->guest_head0_height = 0;
> + }
Hi. Coverity points out (CID 1395986) that we fail to check
the return value from qxl_phys2virt() here. It can return NULL,
in which case we'll segfault trying to dereference it.
thanks
-- PMM
