On Wed, Feb 09, 2022 at 11:19:27AM +0200, Ville Syrjala wrote:
> From: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx>
>
> Make sure we don't assign an error pointer to crtc_state->mode_blob
> as that will break all kinds of places that assume either NULL or a
> valid pointer (eg. drm_property_blob_put()).
>
> Reported-by: fuyufan <fuyufan@xxxxxxxxxx>
> Signed-off-by: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx>
Slapped on a cc:stable just in case this can actually happen
in the wild, and pushed to drm-misc-fixes with Maxime's irc ack
(thanks).
> ---
> drivers/gpu/drm/drm_atomic_uapi.c | 14 ++++++++------
> 1 file changed, 8 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/gpu/drm/drm_atomic_uapi.c b/drivers/gpu/drm/drm_atomic_uapi.c
> index 9781722519c3..54d62fdb4ef9 100644
> --- a/drivers/gpu/drm/drm_atomic_uapi.c
> +++ b/drivers/gpu/drm/drm_atomic_uapi.c
> @@ -76,15 +76,17 @@ int drm_atomic_set_mode_for_crtc(struct drm_crtc_state *state,
> state->mode_blob = NULL;
>
> if (mode) {
> + struct drm_property_blob *blob;
> +
> drm_mode_convert_to_umode(&umode, mode);
> - state->mode_blob =
> - drm_property_create_blob(state->crtc->dev,
> - sizeof(umode),
> - &umode);
> - if (IS_ERR(state->mode_blob))
> - return PTR_ERR(state->mode_blob);
> + blob = drm_property_create_blob(crtc->dev,
> + sizeof(umode), &umode);
> + if (IS_ERR(blob))
> + return PTR_ERR(blob);
>
> drm_mode_copy(&state->mode, mode);
> +
> + state->mode_blob = blob;
> state->enable = true;
> drm_dbg_atomic(crtc->dev,
> "Set [MODE:%s] for [CRTC:%d:%s] state %p\n",
> --
> 2.34.1
--
Ville Syrjälä
Intel
