[RTNETLINK] Fix & cleanup rtm_min/rtm_max

Converts rtm_min and rtm_max arrays to use c99 designated
initializers for easier insertion of new message families.
RTM_GETMULTICAST and RTM_GETANYCAST did not have the minimal
message size specified which means that the netlink message
was parsed for routing attributes starting from the header.
Adds the proper minimal message sizes for these messages
(netlink header + common rtnetlink header) to fix this issue.

Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/linux/rtnetlink.h

@@ -93,6 +93,8 @@ enum {
 #define RTM_MAX		(((__RTM_MAX + 3) & ~3) - 1)
 };
 
+#define RTM_FAM(cmd)	(((cmd) - RTM_BASE) >> 2)
+
 /* 
    Generic structure for encapsulation of optional route information.
    It is reminiscent of sockaddr, but with sa_family replaced

net/core/rtnetlink.c

@@ -88,28 +88,31 @@ struct rtnetlink_link * rtnetlink_links[NPROTO];
 
 static const int rtm_min[(RTM_MAX+1-RTM_BASE)/4] =
 {
-	NLMSG_LENGTH(sizeof(struct ifinfomsg)),
-	NLMSG_LENGTH(sizeof(struct ifaddrmsg)),
-	NLMSG_LENGTH(sizeof(struct rtmsg)),
-	NLMSG_LENGTH(sizeof(struct ndmsg)),
-	NLMSG_LENGTH(sizeof(struct rtmsg)),
-	NLMSG_LENGTH(sizeof(struct tcmsg)),
-	NLMSG_LENGTH(sizeof(struct tcmsg)),
-	NLMSG_LENGTH(sizeof(struct tcmsg)),
-	NLMSG_LENGTH(sizeof(struct tcamsg))
+	[RTM_FAM(RTM_NEWLINK)]      = NLMSG_LENGTH(sizeof(struct ifinfomsg)),
+	[RTM_FAM(RTM_NEWADDR)]      = NLMSG_LENGTH(sizeof(struct ifaddrmsg)),
+	[RTM_FAM(RTM_NEWROUTE)]     = NLMSG_LENGTH(sizeof(struct rtmsg)),
+	[RTM_FAM(RTM_NEWNEIGH)]     = NLMSG_LENGTH(sizeof(struct ndmsg)),
+	[RTM_FAM(RTM_NEWRULE)]      = NLMSG_LENGTH(sizeof(struct rtmsg)),
+	[RTM_FAM(RTM_NEWQDISC)]     = NLMSG_LENGTH(sizeof(struct tcmsg)),
+	[RTM_FAM(RTM_NEWTCLASS)]    = NLMSG_LENGTH(sizeof(struct tcmsg)),
+	[RTM_FAM(RTM_NEWTFILTER)]   = NLMSG_LENGTH(sizeof(struct tcmsg)),
+	[RTM_FAM(RTM_NEWACTION)]    = NLMSG_LENGTH(sizeof(struct tcamsg)),
+	[RTM_FAM(RTM_NEWPREFIX)]    = NLMSG_LENGTH(sizeof(struct rtgenmsg)),
+	[RTM_FAM(RTM_GETMULTICAST)] = NLMSG_LENGTH(sizeof(struct rtgenmsg)),
+	[RTM_FAM(RTM_GETANYCAST)]   = NLMSG_LENGTH(sizeof(struct rtgenmsg)),
 };
 
 static const int rta_max[(RTM_MAX+1-RTM_BASE)/4] =
 {
-	IFLA_MAX,
-	IFA_MAX,
-	RTA_MAX,
-	NDA_MAX,
-	RTA_MAX,
-	TCA_MAX,
-	TCA_MAX,
-	TCA_MAX,
-	TCAA_MAX
+	[RTM_FAM(RTM_NEWLINK)]      = IFLA_MAX,
+	[RTM_FAM(RTM_NEWADDR)]      = IFA_MAX,
+	[RTM_FAM(RTM_NEWROUTE)]     = RTA_MAX,
+	[RTM_FAM(RTM_NEWNEIGH)]     = NDA_MAX,
+	[RTM_FAM(RTM_NEWRULE)]      = RTA_MAX,
+	[RTM_FAM(RTM_NEWQDISC)]     = TCA_MAX,
+	[RTM_FAM(RTM_NEWTCLASS)]    = TCA_MAX,
+	[RTM_FAM(RTM_NEWTFILTER)]   = TCA_MAX,
+	[RTM_FAM(RTM_NEWACTION)]    = TCAA_MAX,
 };
 
 void __rta_fill(struct sk_buff *skb, int attrtype, int attrlen, const void *data)