diff --git a/include/linux/skmsg.h b/include/linux/skmsg.h
index 2a11e9d91dfa..eb8f6cb84c10 100644
--- a/include/linux/skmsg.h
+++ b/include/linux/skmsg.h
@@ -36,6 +36,9 @@ struct sk_msg_sg {
 	struct scatterlist		data[MAX_MSG_FRAGS + 1];
 };
 
+/* UAPI in filter.c depends on struct sk_msg_sg being first element. If
+ * this is moved filter.c also must be updated.
+ */
 struct sk_msg {
 	struct sk_msg_sg		sg;
 	void				*data;
diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
index 1d324c2cbca2..91c43884f295 100644
--- a/include/uapi/linux/bpf.h
+++ b/include/uapi/linux/bpf.h
@@ -2665,6 +2665,7 @@ struct sk_msg_md {
 	__u32 local_ip6[4];	/* Stored in network byte order */
 	__u32 remote_port;	/* Stored in network byte order */
 	__u32 local_port;	/* stored in host byte order */
+	__u32 size;		/* Total size of sk_msg */
 };
 
 struct sk_reuseport_md {
diff --git a/net/core/filter.c b/net/core/filter.c
index f9348806e843..3a3b21726fb5 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -7530,6 +7530,12 @@ static u32 sk_msg_convert_ctx_access(enum bpf_access_type type,
 		*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
 				      offsetof(struct sock_common, skc_num));
 		break;
+
+	case offsetof(struct sk_msg_md, size):
+		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_msg_sg, size),
+				      si->dst_reg, si->src_reg,
+				      offsetof(struct sk_msg_sg, size));
+		break;
 	}
 
 	return insn - insn_buf;