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, 44 insertions, 0 deletions

diff --git a/block/partitions/mac.h b/block/partitions/mac.h
new file mode 100644
index 000000000..0e41c9da7
--- /dev/null
+++ b/block/partitions/mac.h
@@ -0,0 +1,44 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ *  fs/partitions/mac.h
+ */
+
+#define MAC_PARTITION_MAGIC	0x504d
+
+/* type field value for A/UX or other Unix partitions */
+#define APPLE_AUX_TYPE	"Apple_UNIX_SVR2"
+
+struct mac_partition {
+	__be16	signature;	/* expected to be MAC_PARTITION_MAGIC */
+	__be16	res1;
+	__be32	map_count;	/* # blocks in partition map */
+	__be32	start_block;	/* absolute starting block # of partition */
+	__be32	block_count;	/* number of blocks in partition */
+	char	name[32];	/* partition name */
+	char	type[32];	/* string type description */
+	__be32	data_start;	/* rel block # of first data block */
+	__be32	data_count;	/* number of data blocks */
+	__be32	status;		/* partition status bits */
+	__be32	boot_start;
+	__be32	boot_size;
+	__be32	boot_load;
+	__be32	boot_load2;
+	__be32	boot_entry;
+	__be32	boot_entry2;
+	__be32	boot_cksum;
+	char	processor[16];	/* identifies ISA of boot */
+	/* there is more stuff after this that we don't need */
+};
+
+#define MAC_STATUS_BOOTABLE	8	/* partition is bootable */
+
+#define MAC_DRIVER_MAGIC	0x4552
+
+/* Driver descriptor structure, in block 0 */
+struct mac_driver_desc {
+	__be16	signature;	/* expected to be MAC_DRIVER_MAGIC */
+	__be16	block_size;
+	__be32	block_count;
+    /* ... more stuff */
+};
+