af_unix: Remove single nest in manage_oob().

This is a prep for the later fix.

No functional change intended.
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://patch.msgid.link/20240905193240.17565-2-kuniyu@amazon.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

net/unix/af_unix.c

@@ -2654,11 +2654,10 @@ static int unix_stream_recv_urg(struct unix_stream_read_state *state)
 static struct sk_buff *manage_oob(struct sk_buff *skb, struct sock *sk,
 				  int flags, int copied)
 {
+	struct sk_buff *unlinked_skb = NULL;
 	struct unix_sock *u = unix_sk(sk);
 
 	if (!unix_skb_len(skb)) {
-		struct sk_buff *unlinked_skb = NULL;
-
 		spin_lock(&sk->sk_receive_queue.lock);
 
 		if (copied && (!u->oob_skb || skb == u->oob_skb)) {
@@ -2674,12 +2673,14 @@ static struct sk_buff *manage_oob(struct sk_buff *skb, struct sock *sk,
 		spin_unlock(&sk->sk_receive_queue.lock);
 
 		consume_skb(unlinked_skb);
-	} else {
-		struct sk_buff *unlinked_skb = NULL;
+		return skb;
+	}
 
 	spin_lock(&sk->sk_receive_queue.lock);
 
-		if (skb == u->oob_skb) {
+	if (skb != u->oob_skb)
+		goto unlock;
+
 	if (copied) {
 		skb = NULL;
 	} else if (!(flags & MSG_PEEK)) {
@@ -2693,12 +2694,12 @@ static struct sk_buff *manage_oob(struct sk_buff *skb, struct sock *sk,
 	} else if (!sock_flag(sk, SOCK_URGINLINE)) {
 		skb = skb_peek_next(skb, &sk->sk_receive_queue);
 	}
-		}
 
+unlock:
 	spin_unlock(&sk->sk_receive_queue.lock);
 
 	kfree_skb(unlinked_skb);
-	}
+
 	return skb;
 }
 #endif