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, 79 insertions, 0 deletions

diff --git a/tools/iio/iio_utils.h b/tools/iio/iio_utils.h
new file mode 100644
index 000000000..8c72f002d
--- /dev/null
+++ b/tools/iio/iio_utils.h
@@ -0,0 +1,79 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+#ifndef _IIO_UTILS_H_
+#define _IIO_UTILS_H_
+
+/* IIO - useful set of util functionality
+ *
+ * Copyright (c) 2008 Jonathan Cameron
+ */
+
+#include <stdint.h>
+
+/* Made up value to limit allocation sizes */
+#define IIO_MAX_NAME_LENGTH 64
+
+#define FORMAT_SCAN_ELEMENTS_DIR "%s/buffer%d"
+#define FORMAT_EVENTS_DIR "%s/events"
+#define FORMAT_TYPE_FILE "%s_type"
+
+#define ARRAY_SIZE(arr) (sizeof(arr) / sizeof(arr[0]))
+
+extern const char *iio_dir;
+
+/**
+ * struct iio_channel_info - information about a given channel
+ * @name: channel name
+ * @generic_name: general name for channel type
+ * @scale: scale factor to be applied for conversion to si units
+ * @offset: offset to be applied for conversion to si units
+ * @index: the channel index in the buffer output
+ * @bytes: number of bytes occupied in buffer output
+ * @bits_used: number of valid bits of data
+ * @shift: amount of bits to shift right data before applying bit mask
+ * @mask: a bit mask for the raw output
+ * @be: flag if data is big endian
+ * @format: format of the raw value
+ * @location: data offset for this channel inside the buffer (in bytes)
+ **/
+struct iio_channel_info {
+	char *name;
+	char *generic_name;
+	float scale;
+	float offset;
+	unsigned index;
+	unsigned bytes;
+	unsigned bits_used;
+	unsigned shift;
+	uint64_t mask;
+	unsigned be;
+	char format;
+	unsigned location;
+};
+
+static inline int iioutils_check_suffix(const char *str, const char *suffix)
+{
+	return strlen(str) >= strlen(suffix) &&
+		strncmp(str+strlen(str)-strlen(suffix),
+			suffix, strlen(suffix)) == 0;
+}
+
+int iioutils_break_up_name(const char *full_name, char **generic_name);
+int iioutils_get_param_float(float *output, const char *param_name,
+			     const char *device_dir, const char *name,
+			     const char *generic_name);
+void bsort_channel_array_by_index(struct iio_channel_info *ci_array, int cnt);
+int build_channel_array(const char *device_dir, int buffer_idx,
+			struct iio_channel_info **ci_array, int *counter);
+int find_type_by_name(const char *name, const char *type);
+int write_sysfs_int(const char *filename, const char *basedir, int val);
+int write_sysfs_int_and_verify(const char *filename, const char *basedir,
+			       int val);
+int write_sysfs_string_and_verify(const char *filename, const char *basedir,
+				  const char *val);
+int write_sysfs_string(const char *filename, const char *basedir,
+		       const char *val);
+int read_sysfs_posint(const char *filename, const char *basedir);
+int read_sysfs_float(const char *filename, const char *basedir, float *val);
+int read_sysfs_string(const char *filename, const char *basedir, char *str);
+
+#endif /* _IIO_UTILS_H_ */