[IPV6] address: Convert address dumping to new netlink api

Replaces INET6_IFADDR_RTA_SPACE with a new function calculating
the total required message size for all address messages.
Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/ipv6/addrconf.c

@@ -3040,23 +3040,27 @@ static inline int rt_scope(int ifa_scope)
 		return RT_SCOPE_UNIVERSE;
 }
 
-/* Maximum length of ifa_cacheinfo attributes */
-#define INET6_IFADDR_RTA_SPACE \
-		RTA_SPACE(16) /* IFA_ADDRESS */ + \
-		RTA_SPACE(sizeof(struct ifa_cacheinfo)) /* CACHEINFO */
+static inline int inet6_ifaddr_msgsize(void)
+{
+	return nlmsg_total_size(sizeof(struct ifaddrmsg) +
+				nla_total_size(16) +
+				nla_total_size(sizeof(struct ifa_cacheinfo)) +
+				128);
+}
 
 static int inet6_fill_ifaddr(struct sk_buff *skb, struct inet6_ifaddr *ifa,
 			     u32 pid, u32 seq, int event, unsigned int flags)
 {
 	struct nlmsghdr  *nlh;
-	unsigned char	 *b = skb->tail;
 	u32 preferred, valid;
 
-	nlh = NLMSG_NEW(skb, pid, seq, event, sizeof(struct ifaddrmsg), flags);
+	nlh = nlmsg_put(skb, pid, seq, event, sizeof(struct ifaddrmsg), flags);
+	if (nlh == NULL)
+		return -ENOBUFS;
+
 	put_ifaddrmsg(nlh, ifa->prefix_len, ifa->flags, rt_scope(ifa->scope),
 		      ifa->idev->dev->ifindex);
 
-	RTA_PUT(skb, IFA_ADDRESS, 16, &ifa->addr);
 	if (!(ifa->flags&IFA_F_PERMANENT)) {
 		preferred = ifa->prefered_lft;
 		valid = ifa->valid_lft;
@@ -3071,72 +3075,57 @@ static int inet6_fill_ifaddr(struct sk_buff *skb, struct inet6_ifaddr *ifa,
 		valid = INFINITY_LIFE_TIME;
 	}
 
-	if (put_cacheinfo(skb, ifa->cstamp, ifa->tstamp, preferred, valid) < 0)
-		goto rtattr_failure;
+	if (nla_put(skb, IFA_ADDRESS, 16, &ifa->addr) < 0 ||
+	    put_cacheinfo(skb, ifa->cstamp, ifa->tstamp, preferred, valid) < 0)
+		return nlmsg_cancel(skb, nlh);
 
-	nlh->nlmsg_len = skb->tail - b;
-	return skb->len;
-
-nlmsg_failure:
-rtattr_failure:
-	skb_trim(skb, b - skb->data);
-	return -1;
+	return nlmsg_end(skb, nlh);
 }
 
 static int inet6_fill_ifmcaddr(struct sk_buff *skb, struct ifmcaddr6 *ifmca,
 				u32 pid, u32 seq, int event, u16 flags)
 {
 	struct nlmsghdr  *nlh;
-	unsigned char	 *b = skb->tail;
 	u8 scope = RT_SCOPE_UNIVERSE;
 	int ifindex = ifmca->idev->dev->ifindex;
 
 	if (ipv6_addr_scope(&ifmca->mca_addr) & IFA_SITE)
 		scope = RT_SCOPE_SITE;
 
-	nlh = NLMSG_NEW(skb, pid, seq, event, sizeof(struct ifaddrmsg), flags);
-	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
-	RTA_PUT(skb, IFA_MULTICAST, 16, &ifmca->mca_addr);
+	nlh = nlmsg_put(skb, pid, seq, event, sizeof(struct ifaddrmsg), flags);
+	if (nlh == NULL)
+		return -ENOBUFS;
 
-	if (put_cacheinfo(skb, ifmca->mca_cstamp, ifmca->mca_tstamp,
+	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
+	if (nla_put(skb, IFA_MULTICAST, 16, &ifmca->mca_addr) < 0 ||
+	    put_cacheinfo(skb, ifmca->mca_cstamp, ifmca->mca_tstamp,
 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0)
-		goto rtattr_failure;
+		return nlmsg_cancel(skb, nlh);
 
-	nlh->nlmsg_len = skb->tail - b;
-	return skb->len;
-
-nlmsg_failure:
-rtattr_failure:
-	skb_trim(skb, b - skb->data);
-	return -1;
+	return nlmsg_end(skb, nlh);
 }
 
 static int inet6_fill_ifacaddr(struct sk_buff *skb, struct ifacaddr6 *ifaca,
 				u32 pid, u32 seq, int event, unsigned int flags)
 {
 	struct nlmsghdr  *nlh;
-	unsigned char	 *b = skb->tail;
 	u8 scope = RT_SCOPE_UNIVERSE;
 	int ifindex = ifaca->aca_idev->dev->ifindex;
 
 	if (ipv6_addr_scope(&ifaca->aca_addr) & IFA_SITE)
 		scope = RT_SCOPE_SITE;
 
-	nlh = NLMSG_NEW(skb, pid, seq, event, sizeof(struct ifaddrmsg), flags);
-	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
-	RTA_PUT(skb, IFA_ANYCAST, 16, &ifaca->aca_addr);
+	nlh = nlmsg_put(skb, pid, seq, event, sizeof(struct ifaddrmsg), flags);
+	if (nlh == NULL)
+		return -ENOBUFS;
 
-	if (put_cacheinfo(skb, ifaca->aca_cstamp, ifaca->aca_tstamp,
+	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
+	if (nla_put(skb, IFA_ANYCAST, 16, &ifaca->aca_addr) < 0 ||
+	    put_cacheinfo(skb, ifaca->aca_cstamp, ifaca->aca_tstamp,
 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0)
-		goto rtattr_failure;
+		return nlmsg_cancel(skb, nlh);
 
-	nlh->nlmsg_len = skb->tail - b;
-	return skb->len;
-
-nlmsg_failure:
-rtattr_failure:
-	skb_trim(skb, b - skb->data);
-	return -1;
+	return nlmsg_end(skb, nlh);
 }
 
 enum addr_type_t
@@ -3256,7 +3245,6 @@ static int inet6_rtm_getaddr(struct sk_buff *in_skb, struct nlmsghdr* nlh,
 	struct net_device *dev = NULL;
 	struct inet6_ifaddr *ifa;
 	struct sk_buff *skb;
-	int payload = sizeof(struct ifaddrmsg) + INET6_IFADDR_RTA_SPACE;
 	int err;
 
 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy);
@@ -3278,7 +3266,7 @@ static int inet6_rtm_getaddr(struct sk_buff *in_skb, struct nlmsghdr* nlh,
 		goto errout;
 	}
 
-	if ((skb = nlmsg_new(nlmsg_total_size(payload), GFP_KERNEL)) == NULL) {
+	if ((skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_KERNEL)) == NULL) {
 		err = -ENOBUFS;
 		goto errout_ifa;
 	}
@@ -3300,10 +3288,9 @@ static int inet6_rtm_getaddr(struct sk_buff *in_skb, struct nlmsghdr* nlh,
 static void inet6_ifa_notify(int event, struct inet6_ifaddr *ifa)
 {
 	struct sk_buff *skb;
-	int payload = sizeof(struct ifaddrmsg) + INET6_IFADDR_RTA_SPACE;
 	int err = -ENOBUFS;
 
-	skb = nlmsg_new(nlmsg_total_size(payload), GFP_ATOMIC);
+	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_ATOMIC);
 	if (skb == NULL)
 		goto errout;