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, 52 insertions, 0 deletions

diff --git a/tools/perf/util/tracepoint.c b/tools/perf/util/tracepoint.c
new file mode 100644
index 000000000..95377ed5d
--- /dev/null
+++ b/tools/perf/util/tracepoint.c
@@ -0,0 +1,52 @@
+// SPDX-License-Identifier: GPL-2.0
+#include "tracepoint.h"
+
+#include <errno.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/param.h>
+#include <unistd.h>
+
+#include <api/fs/tracing_path.h>
+#include "fncache.h"
+
+int tp_event_has_id(const char *dir_path, struct dirent *evt_dir)
+{
+	char evt_path[MAXPATHLEN];
+	int fd;
+
+	snprintf(evt_path, MAXPATHLEN, "%s/%s/id", dir_path, evt_dir->d_name);
+	fd = open(evt_path, O_RDONLY);
+	if (fd < 0)
+		return -EINVAL;
+	close(fd);
+
+	return 0;
+}
+
+/*
+ * Check whether event is in <debugfs_mount_point>/tracing/events
+ */
+bool is_valid_tracepoint(const char *event_string)
+{
+	char *dst, *path = malloc(strlen(event_string) + 4); /* Space for "/id\0". */
+	bool have_file = false; /* Conservatively return false if memory allocation failed. */
+	const char *src;
+
+	if (!path)
+		return false;
+
+	/* Copy event_string replacing the ':' with '/'. */
+	for (src = event_string, dst = path; *src; src++, dst++)
+		*dst = (*src == ':') ? '/' : *src;
+	/* Add "/id\0". */
+	memcpy(dst, "/id", 4);
+
+	dst = get_events_file(path);
+	if (dst)
+		have_file = file_available(dst);
+	free(dst);
+	free(path);
+	return have_file;
+}