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, 54 insertions, 0 deletions

diff --git a/tools/objtool/builtin-klp.c b/tools/objtool/builtin-klp.c
new file mode 100644
index 000000000..58c3b9bda
--- /dev/null
+++ b/tools/objtool/builtin-klp.c
@@ -0,0 +1,54 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+#include <subcmd/parse-options.h>
+#include <string.h>
+#include <stdlib.h>
+#include <objtool/builtin.h>
+#include <objtool/objtool.h>
+#include <objtool/klp.h>
+
+struct subcmd {
+	const char *name;
+	const char *description;
+	int (*fn)(int, const char **);
+};
+
+static struct subcmd subcmds[] = {
+	{ "checksum",		"Generate per-function checksums",			cmd_klp_checksum, },
+	{ "diff",		"Generate binary diff of two object files",		cmd_klp_diff, },
+	{ "post-link",		"Finalize klp symbols/relocs after module linking",	cmd_klp_post_link, },
+};
+
+static void cmd_klp_usage(void)
+{
+	fprintf(stderr, "usage: objtool klp <subcommand> [<options>]\n\n");
+	fprintf(stderr, "Subcommands:\n");
+
+	for (int i = 0; i < ARRAY_SIZE(subcmds); i++) {
+		struct subcmd *cmd = &subcmds[i];
+
+		fprintf(stderr, "  %s\t%s\n", cmd->name, cmd->description);
+	}
+
+	exit(1);
+}
+
+int cmd_klp(int argc, const char **argv)
+{
+	argc--;
+	argv++;
+
+	if (!argc)
+		cmd_klp_usage();
+
+	if (argc) {
+		for (int i = 0; i < ARRAY_SIZE(subcmds); i++) {
+			struct subcmd *cmd = &subcmds[i];
+
+			if (!strcmp(cmd->name, argv[0]))
+				return cmd->fn(argc, argv);
+		}
+	}
+
+	cmd_klp_usage();
+	return 0;
+}