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, 47 insertions, 0 deletions

diff --git a/samples/bpf/tracex1.bpf.c b/samples/bpf/tracex1.bpf.c
new file mode 100644
index 000000000..ceedf0b1d
--- /dev/null
+++ b/samples/bpf/tracex1.bpf.c
@@ -0,0 +1,47 @@
+/* Copyright (c) 2013-2015 PLUMgrid, http://plumgrid.com
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of version 2 of the GNU General Public
+ * License as published by the Free Software Foundation.
+ */
+#include "vmlinux.h"
+#include "net_shared.h"
+#include <linux/version.h>
+#include <bpf/bpf_helpers.h>
+#include <bpf/bpf_core_read.h>
+#include <bpf/bpf_tracing.h>
+
+/* kprobe is NOT a stable ABI
+ * kernel functions can be removed, renamed or completely change semantics.
+ * Number of arguments and their positions can change, etc.
+ * In such case this bpf+kprobe example will no longer be meaningful
+ */
+SEC("kprobe.multi/__netif_receive_skb_core*")
+int bpf_prog1(struct pt_regs *ctx)
+{
+	/* attaches to kprobe __netif_receive_skb_core,
+	 * looks for packets on loopback device and prints them
+	 * (wildcard is used for avoiding symbol mismatch due to optimization)
+	 */
+	char devname[IFNAMSIZ];
+	struct net_device *dev;
+	struct sk_buff *skb;
+	int len;
+
+	bpf_core_read(&skb, sizeof(skb), (void *)PT_REGS_PARM1(ctx));
+	dev = BPF_CORE_READ(skb, dev);
+	len = BPF_CORE_READ(skb, len);
+
+	BPF_CORE_READ_STR_INTO(&devname, dev, name);
+
+	if (devname[0] == 'l' && devname[1] == 'o') {
+		char fmt[] = "skb %p len %d\n";
+		/* using bpf_trace_printk() for DEBUG ONLY */
+		bpf_trace_printk(fmt, sizeof(fmt), skb, len);
+	}
+
+	return 0;
+}
+
+char _license[] SEC("license") = "GPL";
+u32 _version SEC("version") = LINUX_VERSION_CODE;