drm/mediatek: Add missing IS_ERR check for ovl_adaptor platform devicegrafted

platform_device_register_data() can fail and return an ERR_PTR, but the
return value is used without checking, leading to an invalid pointer
being stored in ddp_comp[].dev and passed to component_match_add() and
mtk_ddp_comp_init(), which could result in a kernel crash.

Add an IS_ERR() check to jump to the error handling path on failure.

Fixes: 0d9eee9118b7 ("drm/mediatek: Add drm ovl_adaptor sub driver for MT8195")
Cc: stable@vger.kernel.org
Signed-off-by: Haojie Li <lihaojie@kylinos.cn>
Reviewed-by: CK Hu <ck.hu@mediatek.com>
Link: https://patchwork.kernel.org/project/linux-mediatek/patch/20260825100845.438893-1-lihaojie@kylinos.cn/
Signed-off-by: Chun-Kuang Hu <chunkuang.hu@kernel.org>

1 files changed, 46 insertions, 0 deletions

diff --git a/Documentation/userspace-api/media/intro.rst b/Documentation/userspace-api/media/intro.rst
new file mode 100644
index 000000000..4a6bd665b
--- /dev/null
+++ b/Documentation/userspace-api/media/intro.rst
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+.. SPDX-License-Identifier: GPL-2.0
+
+============
+Introduction
+============
+
+This document covers the Linux Kernel to Userspace API's used by video
+and radio streaming devices, including video cameras, analog and digital
+TV receiver cards, AM/FM receiver cards, Software Defined Radio (SDR),
+streaming capture and output devices, codec devices and remote controllers.
+
+A typical media device hardware is shown at :ref:`typical_media_device`.
+
+.. _typical_media_device:
+
+.. kernel-figure:: typical_media_device.svg
+    :alt:   typical_media_device.svg
+    :align: center
+
+    Typical Media Device
+
+The media infrastructure API was designed to control such devices. It is
+divided into five parts.
+
+1. The :ref:`first part <v4l2spec>` covers radio, video capture and output,
+   cameras, analog TV devices and codecs.
+
+2. The :ref:`second part <dvbapi>` covers the API used for digital TV and
+   Internet reception via one of the several digital tv standards. While it is
+   called as DVB API, in fact it covers several different video standards
+   including DVB-T/T2, DVB-S/S2, DVB-C, ATSC, ISDB-T, ISDB-S, DTMB, etc. The
+   complete list of supported standards can be found at
+   :c:type:`fe_delivery_system`.
+
+3. The :ref:`third part <remote_controllers>` covers the Remote Controller API.
+
+4. The :ref:`fourth part <media_controller>` covers the Media Controller API.
+
+5. The :ref:`fifth part <cec>` covers the CEC (Consumer Electronics Control) API.
+
+It should also be noted that a media device may also have audio components, like
+mixers, PCM capture, PCM playback, etc, which are controlled via ALSA API.  For
+additional information and for the latest development code, see:
+`https://linuxtv.org <https://linuxtv.org>`__.  For discussing improvements,
+reporting troubles, sending new drivers, etc, please mail to: `Linux Media
+Mailing List (LMML) <http://vger.kernel.org/vger-lists.html#linux-media>`__.