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, 56 insertions, 0 deletions

diff --git a/lib/compat_audit.c b/lib/compat_audit.c
new file mode 100644
index 000000000..fee1dfccd
--- /dev/null
+++ b/lib/compat_audit.c
@@ -0,0 +1,56 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/init.h>
+#include <linux/types.h>
+#include <linux/audit_arch.h>
+#include <asm/unistd32.h>
+
+unsigned int compat_dir_class[] = {
+#include <asm-generic/audit_dir_write.h>
+~0U
+};
+
+unsigned int compat_read_class[] = {
+#include <asm-generic/audit_read.h>
+~0U
+};
+
+unsigned int compat_write_class[] = {
+#include <asm-generic/audit_write.h>
+~0U
+};
+
+unsigned int compat_chattr_class[] = {
+#include <asm-generic/audit_change_attr.h>
+~0U
+};
+
+unsigned int compat_signal_class[] = {
+#include <asm-generic/audit_signal.h>
+~0U
+};
+
+int audit_classify_compat_syscall(int abi, unsigned int syscall)
+{
+	switch (syscall) {
+#ifdef __NR_open
+	case __NR_open:
+		return AUDITSC_OPEN;
+#endif
+#ifdef __NR_openat
+	case __NR_openat:
+		return AUDITSC_OPENAT;
+#endif
+#ifdef __NR_socketcall
+	case __NR_socketcall:
+		return AUDITSC_SOCKETCALL;
+#endif
+	case __NR_execve:
+		return AUDITSC_EXECVE;
+#ifdef __NR_openat2
+	case __NR_openat2:
+		return AUDITSC_OPENAT2;
+#endif
+	default:
+		return AUDITSC_COMPAT;
+	}
+}