ipv6: Allow inet6_dump_addr() to handle more than 64 addresses

Apparently, inet6_dump_addr() is not able to handle more than
64 ipv6 addresses per device. We must break from inner loops
in case skb is full, or else cursor is put at the end of list.
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/ipv6/addrconf.c

@@ -3519,6 +3519,8 @@ static int inet6_dump_addr(struct sk_buff *skb, struct netlink_callback *cb,
 							cb->nlh->nlmsg_seq,
 							RTM_NEWADDR,
 							NLM_F_MULTI);
+				if (err <= 0)
+					break;
 			}
 			break;
 		case MULTICAST_ADDR:
@@ -3532,6 +3534,8 @@ static int inet6_dump_addr(struct sk_buff *skb, struct netlink_callback *cb,
 							  cb->nlh->nlmsg_seq,
 							  RTM_GETMULTICAST,
 							  NLM_F_MULTI);
+				if (err <= 0)
+					break;
 			}
 			break;
 		case ANYCAST_ADDR:
@@ -3545,6 +3549,8 @@ static int inet6_dump_addr(struct sk_buff *skb, struct netlink_callback *cb,
 							  cb->nlh->nlmsg_seq,
 							  RTM_GETANYCAST,
 							  NLM_F_MULTI);
+				if (err <= 0)
+					break;
 			}
 			break;
 		default: