af_unix: take address assignment/hash insertion into a new helper

Duplicated logics in all bind variants (autobind, bind-to-path,
bind-to-abstract) gets taken into a common helper.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/unix/af_unix.c

@@ -262,6 +262,14 @@ static void __unix_insert_socket(struct hlist_head *list, struct sock *sk)
 	sk_add_node(sk, list);
 }
 
+static void __unix_set_addr(struct sock *sk, struct unix_address *addr,
+			    unsigned hash)
+{
+	__unix_remove_socket(sk);
+	smp_store_release(&unix_sk(sk)->addr, addr);
+	__unix_insert_socket(&unix_socket_table[hash], sk);
+}
+
 static inline void unix_remove_socket(struct sock *sk)
 {
 	spin_lock(&unix_table_lock);
@@ -913,9 +921,7 @@ static int unix_autobind(struct socket *sock)
 	}
 	addr->hash ^= sk->sk_type;
 
-	__unix_remove_socket(sk);
-	smp_store_release(&u->addr, addr);
-	__unix_insert_socket(&unix_socket_table[addr->hash], sk);
+	__unix_set_addr(sk, addr, addr->hash);
 	spin_unlock(&unix_table_lock);
 	err = 0;
 
@@ -1018,7 +1024,6 @@ static int unix_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
 	int err;
 	unsigned int hash;
 	struct unix_address *addr;
-	struct hlist_head *list;
 	struct path path = { };
 
 	err = -EINVAL;
@@ -1070,25 +1075,20 @@ static int unix_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
 		hash = d_backing_inode(path.dentry)->i_ino & (UNIX_HASH_SIZE - 1);
 		spin_lock(&unix_table_lock);
 		u->path = path;
-		list = &unix_socket_table[hash];
 	} else {
 		spin_lock(&unix_table_lock);
 		err = -EADDRINUSE;
 		if (__unix_find_socket_byname(net, sunaddr, addr_len,
 					      sk->sk_type, hash)) {
+			spin_unlock(&unix_table_lock);
 			unix_release_addr(addr);
-			goto out_unlock;
+			goto out_up;
 		}
-
-		list = &unix_socket_table[addr->hash];
+		hash = addr->hash;
 	}
 
 	err = 0;
-	__unix_remove_socket(sk);
-	smp_store_release(&u->addr, addr);
-	__unix_insert_socket(list, sk);
-
-out_unlock:
+	__unix_set_addr(sk, addr, hash);
 	spin_unlock(&unix_table_lock);
 out_up:
 	mutex_unlock(&u->bindlock);