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/tools/perf/tests/demangle-ocaml-test.c b/tools/perf/tests/demangle-ocaml-test.c
new file mode 100644
index 000000000..612c788b7
--- /dev/null
+++ b/tools/perf/tests/demangle-ocaml-test.c
@@ -0,0 +1,44 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <string.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include "debug.h"
+#include "symbol.h"
+#include "tests.h"
+
+static int test__demangle_ocaml(struct test_suite *test __maybe_unused, int subtest __maybe_unused)
+{
+	int ret = TEST_OK;
+	char *buf = NULL;
+	size_t i;
+
+	struct {
+		const char *mangled, *demangled;
+	} test_cases[] = {
+		{ "main",
+		  NULL },
+		{ "camlStdlib__array__map_154",
+		  "Stdlib.array.map_154" },
+		{ "camlStdlib__anon_fn$5bstdlib$2eml$3a334$2c0$2d$2d54$5d_1453",
+		  "Stdlib.anon_fn[stdlib.ml:334,0--54]_1453" },
+		{ "camlStdlib__bytes__$2b$2b_2205",
+		  "Stdlib.bytes.++_2205" },
+	};
+
+	for (i = 0; i < ARRAY_SIZE(test_cases); i++) {
+		buf = dso__demangle_sym(/*dso=*/NULL, /*kmodule=*/0, test_cases[i].mangled);
+		if ((buf == NULL && test_cases[i].demangled != NULL)
+				|| (buf != NULL && test_cases[i].demangled == NULL)
+				|| (buf != NULL && strcmp(buf, test_cases[i].demangled))) {
+			pr_debug("FAILED: %s: %s != %s\n", test_cases[i].mangled,
+				 buf == NULL ? "(null)" : buf,
+				 test_cases[i].demangled == NULL ? "(null)" : test_cases[i].demangled);
+			ret = TEST_FAIL;
+		}
+		free(buf);
+	}
+
+	return ret;
+}
+
+DEFINE_SUITE("Demangle OCaml", demangle_ocaml);