arp: Remove a nest in arp_req_get().

This is a prep patch to make the following changes tidy.

No functional change intended.

Signed-off-by: Kuniyuki Iwashima <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>

Author: q2ven

net/ipv4/arp.c

@@ -1138,23 +1138,28 @@ static int arp_req_get(struct arpreq *r, struct net_device *dev)
 {
 	__be32 ip = ((struct sockaddr_in *) &r->arp_pa)->sin_addr.s_addr;
 	struct neighbour *neigh;
-	int err = -ENXIO;
 
 	neigh = neigh_lookup(&arp_tbl, &ip, dev);
-	if (neigh) {
-		if (!(READ_ONCE(neigh->nud_state) & NUD_NOARP)) {
-			read_lock_bh(&neigh->lock);
-			memcpy(r->arp_ha.sa_data, neigh->ha,
-			       min(dev->addr_len, sizeof(r->arp_ha.sa_data_min)));
-			r->arp_flags = arp_state_to_flags(neigh);
-			read_unlock_bh(&neigh->lock);
-			r->arp_ha.sa_family = dev->type;
-			strscpy(r->arp_dev, dev->name, sizeof(r->arp_dev));
-			err = 0;
-		}
+	if (!neigh)
+		return -ENXIO;
+
+	if (READ_ONCE(neigh->nud_state) & NUD_NOARP) {
 		neigh_release(neigh);
+		return -ENXIO;
 	}
-	return err;
+
+	read_lock_bh(&neigh->lock);
+	memcpy(r->arp_ha.sa_data, neigh->ha,
+	       min(dev->addr_len, sizeof(r->arp_ha.sa_data_min)));
+	r->arp_flags = arp_state_to_flags(neigh);
+	read_unlock_bh(&neigh->lock);
+
+	neigh_release(neigh);
+
+	r->arp_ha.sa_family = dev->type;
+	strscpy(r->arp_dev, dev->name, sizeof(r->arp_dev));
+
+	return 0;
 }
 
 int arp_invalidate(struct net_device *dev, __be32 ip, bool force)