nettrace: fix compile error on arm64

Signed-off-by: Menglong Dong <imagedong@tencent.com>

Author: menglongdong

shared/bpf/skb_parse.h

@@ -323,6 +323,19 @@ static try_inline int probe_parse_ip(void *ip, parse_ctx_t *ctx)
 	return -1;
 }
 
+static __always_inline u8 sk_get_protocol(struct sock *sk)
+{
+	u32 flags = _(((u32 *)(&sk->__sk_flags_offset))[0]);
+	u8 l4_proto;
+
+#ifdef CONFIG_CPU_BIG_ENDIAN
+	l4_proto = (flags << 8) >> 24;
+#else
+	l4_proto = (flags << 16) >> 24;
+#endif
+	return l4_proto;
+}
+
 static try_inline int __probe_parse_sk(parse_ctx_t *ctx)
 {
 	struct inet_connection_sock *icsk;
@@ -354,15 +367,17 @@ static try_inline int __probe_parse_sk(parse_ctx_t *ctx)
 	if (FILTER_CHECK(ctx, l3_proto, l3_proto))
 		goto err;
 
+#ifdef COMPAT_MODE
 #ifdef BPF_FEAT_SK_PRPTOCOL_LEGACY
-	u32 flags = _(((u32 *)(&sk->__sk_flags_offset))[0]);
-#ifdef CONFIG_CPU_BIG_ENDIAN
-	l4_proto = (flags << 8) >> 24;
+	l4_proto = sk_get_protocol(sk);
 #else
-	l4_proto = (flags << 16) >> 24;
+	l4_proto = _C(sk, sk_protocol);
 #endif
 #else
-	l4_proto = _C(sk, sk_protocol);
+	if (bpf_core_field_size(sk->sk_protocol) == 2)
+		l4_proto = _C(sk, sk_protocol);
+	else
+		l4_proto = sk_get_protocol(sk);
 #endif
 
 	if (l4_proto == IPPROTO_IP)

shared/bpf/vmlinux_arm64.h

@@ -8018,16 +8018,16 @@ struct sock {
 	unsigned int sk_gso_max_size;
 	gfp_t sk_allocation;
 	__u32 sk_txhash;
-	unsigned int __sk_flags_offset[0];
-	unsigned int sk_padding: 1;
-	unsigned int sk_kern_sock: 1;
-	unsigned int sk_no_check_tx: 1;
-	unsigned int sk_no_check_rx: 1;
-	unsigned int sk_userlocks: 4;
-	unsigned int sk_protocol: 8;
-	unsigned int sk_type: 16;
-	u16 sk_gso_max_segs;
+	unsigned int		__sk_flags_offset[0];
+	u8 sk_padding: 1;
+	u8 sk_kern_sock: 1;
+	u8 sk_no_check_tx: 1;
+	u8 sk_no_check_rx: 1;
+	u8 sk_userlocks: 4;
 	u8 sk_pacing_shift;
+	u16 sk_type;
+	u16 sk_protocol;
+	u16 sk_gso_max_segs;
 	long unsigned int sk_lingertime;
 	struct proto *sk_prot_creator;
 	rwlock_t sk_callback_lock;

shared/bpf/vmlinux_x86.h

@@ -8733,6 +8733,7 @@ struct sock {
 	unsigned int sk_gso_max_size;
 	gfp_t sk_allocation;
 	__u32 sk_txhash;
+	unsigned int		__sk_flags_offset[0];
 	u8 sk_padding: 1;
 	u8 sk_kern_sock: 1;
 	u8 sk_no_check_tx: 1;