[PATCH net-next 0/2] Get rid of attribute parsing in rtnetlink_rcv_msg()

[PATCH net-next 0/2] Get rid of attribute parsing in rtnetlink_rcv_msg()

[Thomas Graf]

We have been wanting to get rid of rta_buf for a while. It is error
prone as it requires subsystems, especially modules, that register a
rtnetlink mesage type to also modify rtnetlink.c and thus require
the recompilation of the kernel. DECnet is the only user left so after
converting it we can safely remove it

Thomas Graf (2):
  decnet: Parse netlink attributes on our own
  rtnetlink: Remove passing of attributes into rtnl_doit functions

 include/net/dn_fib.h    |  28 ++-----
 include/net/rtnetlink.h |   2 +-
 net/bridge/br_mdb.c     |   4 +-
 net/can/gw.c            |   5 +-
 net/core/fib_rules.c    |   4 +-
 net/core/neighbour.c    |   6 +-
 net/core/rtnetlink.c    |  82 ++----------------
 net/dcb/dcbnl.c         |   2 +-
 net/decnet/dn_dev.c     |   4 +-
 net/decnet/dn_fib.c     | 215 ++++++++++++++++++++++++++----------------------
 net/decnet/dn_route.c   |  29 ++++---
 net/decnet/dn_table.c   |  42 +++++-----
 net/ipv4/devinet.c      |   7 +-
 net/ipv4/fib_frontend.c |   4 +-
 net/ipv4/route.c        |   2 +-
 net/ipv6/addrconf.c     |  10 +--
 net/ipv6/addrlabel.c    |   6 +-
 net/ipv6/route.c        |   6 +-
 net/phonet/pn_netlink.c |   4 +-
 net/sched/act_api.c     |   2 +-
 net/sched/cls_api.c     |   2 +-
 net/sched/sch_api.c     |   6 +-
 22 files changed, 207 insertions(+), 265 deletions(-)

-- 
1.7.11.7

[PATCH net-next 1/2] decnet: Parse netlink attributes on our own

[Thomas Graf]

decnet is the only subsystem left that is relying on the global
netlink attribute buffer rta_buf. It's horrible design and we
want to get rid of it.

This converts all of decnet to do implicit attribute parsing. It
also gets rid of the error prone struct dn_kern_rta.

Yes, the fib_magic() stuff is not pretty.

It's compiled tested but I need someone with appropriate hardware
to test the patch since I don't have access to it.

Cc: linux-decnet-user@lists.sourceforge.net
Signed-off-by: Thomas Graf <tgraf@suug.ch>
---
 include/net/dn_fib.h  |  28 ++-----
 net/decnet/dn_fib.c   | 211 +++++++++++++++++++++++++++-----------------------
 net/decnet/dn_route.c |  27 ++++---
 net/decnet/dn_table.c |  42 +++++-----
 4 files changed, 160 insertions(+), 148 deletions(-)

diff --git a/include/net/dn_fib.h b/include/net/dn_fib.h
index 1ee9d4b..74004af 100644
--- a/include/net/dn_fib.h
+++ b/include/net/dn_fib.h
@@ -1,24 +1,9 @@
 #ifndef _NET_DN_FIB_H
 #define _NET_DN_FIB_H
 
-/* WARNING: The ordering of these elements must match ordering
- *          of RTA_* rtnetlink attribute numbers.
- */
-struct dn_kern_rta {
-        void            *rta_dst;
-        void            *rta_src;
-        int             *rta_iif;
-        int             *rta_oif;
-        void            *rta_gw;
-        u32             *rta_priority;
-        void            *rta_prefsrc;
-        struct rtattr   *rta_mx;
-        struct rtattr   *rta_mp;
-        unsigned char   *rta_protoinfo;
-        u32             *rta_flow;
-        struct rta_cacheinfo *rta_ci;
-	struct rta_session *rta_sess;
-};
+#include <linux/netlink.h>
+
+extern const struct nla_policy rtm_dn_policy[];
 
 struct dn_fib_res {
 	struct fib_rule *r;
@@ -93,10 +78,10 @@ struct dn_fib_table {
 	u32 n;
 
 	int (*insert)(struct dn_fib_table *t, struct rtmsg *r, 
-			struct dn_kern_rta *rta, struct nlmsghdr *n, 
+			struct nlattr *attrs[], struct nlmsghdr *n,
 			struct netlink_skb_parms *req);
 	int (*delete)(struct dn_fib_table *t, struct rtmsg *r,
-			struct dn_kern_rta *rta, struct nlmsghdr *n,
+			struct nlattr *attrs[], struct nlmsghdr *n,
 			struct netlink_skb_parms *req);
 	int (*lookup)(struct dn_fib_table *t, const struct flowidn *fld,
 			struct dn_fib_res *res);
@@ -116,13 +101,12 @@ extern void dn_fib_cleanup(void);
 extern int dn_fib_ioctl(struct socket *sock, unsigned int cmd, 
 			unsigned long arg);
 extern struct dn_fib_info *dn_fib_create_info(const struct rtmsg *r, 
-				struct dn_kern_rta *rta, 
+				struct nlattr *attrs[],
 				const struct nlmsghdr *nlh, int *errp);
 extern int dn_fib_semantic_match(int type, struct dn_fib_info *fi, 
 			const struct flowidn *fld,
 			struct dn_fib_res *res);
 extern void dn_fib_release_info(struct dn_fib_info *fi);
-extern __le16 dn_fib_get_attr16(struct rtattr *attr, int attrlen, int type);
 extern void dn_fib_flush(void);
 extern void dn_fib_select_multipath(const struct flowidn *fld,
 					struct dn_fib_res *res);
diff --git a/net/decnet/dn_fib.c b/net/decnet/dn_fib.c
index e36614e..42a8048 100644
--- a/net/decnet/dn_fib.c
+++ b/net/decnet/dn_fib.c
@@ -145,22 +145,10 @@ static inline struct dn_fib_info *dn_fib_find_info(const struct dn_fib_info *nfi
 	return NULL;
 }
 
-__le16 dn_fib_get_attr16(struct rtattr *attr, int attrlen, int type)
+static int dn_fib_count_nhs(const struct nlattr *attr)
 {
-	while(RTA_OK(attr,attrlen)) {
-		if (attr->rta_type == type)
-			return *(__le16*)RTA_DATA(attr);
-		attr = RTA_NEXT(attr, attrlen);
-	}
-
-	return 0;
-}
-
-static int dn_fib_count_nhs(struct rtattr *rta)
-{
-	int nhs = 0;
-	struct rtnexthop *nhp = RTA_DATA(rta);
-	int nhlen = RTA_PAYLOAD(rta);
+	struct rtnexthop *nhp = nla_data(attr);
+	int nhs = 0, nhlen = nla_len(attr);
 
 	while(nhlen >= (int)sizeof(struct rtnexthop)) {
 		if ((nhlen -= nhp->rtnh_len) < 0)
@@ -172,10 +160,11 @@ static int dn_fib_count_nhs(struct rtattr *rta)
 	return nhs;
 }
 
-static int dn_fib_get_nhs(struct dn_fib_info *fi, const struct rtattr *rta, const struct rtmsg *r)
+static int dn_fib_get_nhs(struct dn_fib_info *fi, const struct nlattr *attr,
+			  const struct rtmsg *r)
 {
-	struct rtnexthop *nhp = RTA_DATA(rta);
-	int nhlen = RTA_PAYLOAD(rta);
+	struct rtnexthop *nhp = nla_data(attr);
+	int nhlen = nla_len(attr);
 
 	change_nexthops(fi) {
 		int attrlen = nhlen - sizeof(struct rtnexthop);
@@ -187,7 +176,10 @@ static int dn_fib_get_nhs(struct dn_fib_info *fi, const struct rtattr *rta, cons
 		nh->nh_weight = nhp->rtnh_hops + 1;
 
 		if (attrlen) {
-			nh->nh_gw = dn_fib_get_attr16(RTNH_DATA(nhp), attrlen, RTA_GATEWAY);
+			struct nlattr *gw_attr;
+
+			gw_attr = nla_find((struct nlattr *) (nhp + 1), attrlen, RTA_GATEWAY);
+			nh->nh_gw = gw_attr ? nla_get_le16(gw_attr) : 0;
 		}
 		nhp = RTNH_NEXT(nhp);
 	} endfor_nexthops(fi);
@@ -268,7 +260,8 @@ out:
 }
 
 
-struct dn_fib_info *dn_fib_create_info(const struct rtmsg *r, struct dn_kern_rta *rta, const struct nlmsghdr *nlh, int *errp)
+struct dn_fib_info *dn_fib_create_info(const struct rtmsg *r, struct nlattr *attrs[],
+				       const struct nlmsghdr *nlh, int *errp)
 {
 	int err;
 	struct dn_fib_info *fi = NULL;
@@ -281,11 +274,9 @@ struct dn_fib_info *dn_fib_create_info(const struct rtmsg *r, struct dn_kern_rta
 	if (dn_fib_props[r->rtm_type].scope > r->rtm_scope)
 		goto err_inval;
 
-	if (rta->rta_mp) {
-		nhs = dn_fib_count_nhs(rta->rta_mp);
-		if (nhs == 0)
-			goto err_inval;
-	}
+	if (attrs[RTA_MULTIPATH] &&
+	    (nhs = dn_fib_count_nhs(attrs[RTA_MULTIPATH])) == 0)
+		goto err_inval;
 
 	fi = kzalloc(sizeof(*fi)+nhs*sizeof(struct dn_fib_nh), GFP_KERNEL);
 	err = -ENOBUFS;
@@ -295,53 +286,65 @@ struct dn_fib_info *dn_fib_create_info(const struct rtmsg *r, struct dn_kern_rta
 	fi->fib_protocol = r->rtm_protocol;
 	fi->fib_nhs = nhs;
 	fi->fib_flags = r->rtm_flags;
-	if (rta->rta_priority)
-		fi->fib_priority = *rta->rta_priority;
-	if (rta->rta_mx) {
-		int attrlen = RTA_PAYLOAD(rta->rta_mx);
-		struct rtattr *attr = RTA_DATA(rta->rta_mx);
 
-		while(RTA_OK(attr, attrlen)) {
-			unsigned int flavour = attr->rta_type;
+	if (attrs[RTA_PRIORITY])
+		fi->fib_priority = nla_get_u32(attrs[RTA_PRIORITY]);
+
+	if (attrs[RTA_METRICS]) {
+		struct nlattr *attr;
+		int rem;
 
-			if (flavour) {
-				if (flavour > RTAX_MAX)
+		nla_for_each_nested(attr, attrs[RTA_METRICS], rem) {
+			int type = nla_type(attr);
+
+			if (type) {
+				if (type > RTAX_MAX || nla_len(attr) < 4)
 					goto err_inval;
-				fi->fib_metrics[flavour-1] = *(unsigned int *)RTA_DATA(attr);
+
+				fi->fib_metrics[type-1] = nla_get_u32(attr);
 			}
-			attr = RTA_NEXT(attr, attrlen);
 		}
 	}
-	if (rta->rta_prefsrc)
-		memcpy(&fi->fib_prefsrc, rta->rta_prefsrc, 2);
 
-	if (rta->rta_mp) {
-		if ((err = dn_fib_get_nhs(fi, rta->rta_mp, r)) != 0)
+	if (attrs[RTA_PREFSRC])
+		fi->fib_prefsrc = nla_get_le16(attrs[RTA_PREFSRC]);
+
+	if (attrs[RTA_MULTIPATH]) {
+		if ((err = dn_fib_get_nhs(fi, attrs[RTA_MULTIPATH], r)) != 0)
 			goto failure;
-		if (rta->rta_oif && fi->fib_nh->nh_oif != *rta->rta_oif)
+
+		if (attrs[RTA_OIF] &&
+		    fi->fib_nh->nh_oif != nla_get_u32(attrs[RTA_OIF]))
 			goto err_inval;
-		if (rta->rta_gw && memcmp(&fi->fib_nh->nh_gw, rta->rta_gw, 2))
+
+		if (attrs[RTA_GATEWAY] &&
+		    fi->fib_nh->nh_gw != nla_get_le16(attrs[RTA_GATEWAY]))
 			goto err_inval;
 	} else {
 		struct dn_fib_nh *nh = fi->fib_nh;
-		if (rta->rta_oif)
-			nh->nh_oif = *rta->rta_oif;
-		if (rta->rta_gw)
-			memcpy(&nh->nh_gw, rta->rta_gw, 2);
+
+		if (attrs[RTA_OIF])
+			nh->nh_oif = nla_get_u32(attrs[RTA_OIF]);
+
+		if (attrs[RTA_GATEWAY])
+			nh->nh_gw = nla_get_le16(attrs[RTA_GATEWAY]);
+
 		nh->nh_flags = r->rtm_flags;
 		nh->nh_weight = 1;
 	}
 
 	if (r->rtm_type == RTN_NAT) {
-		if (rta->rta_gw == NULL || nhs != 1 || rta->rta_oif)
+		if (!attrs[RTA_GATEWAY] || nhs != 1 || attrs[RTA_OIF])
 			goto err_inval;
-		memcpy(&fi->fib_nh->nh_gw, rta->rta_gw, 2);
+
+		fi->fib_nh->nh_gw = nla_get_le16(attrs[RTA_GATEWAY]);
 		goto link_it;
 	}
 
 	if (dn_fib_props[r->rtm_type].error) {
-		if (rta->rta_gw || rta->rta_oif || rta->rta_mp)
+		if (attrs[RTA_GATEWAY] || attrs[RTA_OIF] || attrs[RTA_MULTIPATH])
 			goto err_inval;
+
 		goto link_it;
 	}
 
@@ -367,8 +370,8 @@ struct dn_fib_info *dn_fib_create_info(const struct rtmsg *r, struct dn_kern_rta
 	}
 
 	if (fi->fib_prefsrc) {
-		if (r->rtm_type != RTN_LOCAL || rta->rta_dst == NULL ||
-		    memcmp(&fi->fib_prefsrc, rta->rta_dst, 2))
+		if (r->rtm_type != RTN_LOCAL || !attrs[RTA_DST] ||
+		    fi->fib_prefsrc != nla_get_le16(attrs[RTA_DST]))
 			if (dnet_addr_type(fi->fib_prefsrc) != RTN_LOCAL)
 				goto err_inval;
 	}
@@ -486,29 +489,24 @@ void dn_fib_select_multipath(const struct flowidn *fld, struct dn_fib_res *res)
 	spin_unlock_bh(&dn_fib_multipath_lock);
 }
 
+const struct nla_policy rtm_dn_policy[RTA_MAX + 1] = {
+	[RTA_DST]		= { .type = NLA_U16 },
+	[RTA_SRC]		= { .type = NLA_U16 },
+	[RTA_IIF]		= { .type = NLA_U32 },
+	[RTA_OIF]		= { .type = NLA_U32 },
+	[RTA_GATEWAY]		= { .type = NLA_U16 },
+	[RTA_PRIORITY]		= { .type = NLA_U32 },
+	[RTA_PREFSRC]		= { .type = NLA_U16 },
+	[RTA_METRICS]		= { .type = NLA_NESTED },
+	[RTA_MULTIPATH]		= { .type = NLA_NESTED },
+	[RTA_TABLE]		= { .type = NLA_U32 },
+	[RTA_MARK]		= { .type = NLA_U32 },
+};
 
-static int dn_fib_check_attr(struct rtmsg *r, struct rtattr **rta)
-{
-	int i;
-
-	for(i = 1; i <= RTA_MAX; i++) {
-		struct rtattr *attr = rta[i-1];
-		if (attr) {
-			if (RTA_PAYLOAD(attr) < 4 && RTA_PAYLOAD(attr) != 2)
-				return -EINVAL;
-			if (i != RTA_MULTIPATH && i != RTA_METRICS &&
-			    i != RTA_TABLE)
-				rta[i-1] = (struct rtattr *)RTA_DATA(attr);
-		}
-	}
-
-	return 0;
-}
-
-static inline u32 rtm_get_table(struct rtattr **rta, u8 table)
+static inline u32 rtm_get_table(struct nlattr *attrs[], u8 table)
 {
-	if (rta[RTA_TABLE - 1])
-		table = nla_get_u32((struct nlattr *) rta[RTA_TABLE - 1]);
+	if (attrs[RTA_TABLE])
+		table = nla_get_u32(attrs[RTA_TABLE]);
 
 	return table;
 }
@@ -517,8 +515,9 @@ static int dn_fib_rtm_delroute(struct sk_buff *skb, struct nlmsghdr *nlh, void *
 {
 	struct net *net = sock_net(skb->sk);
 	struct dn_fib_table *tb;
-	struct rtattr **rta = arg;
-	struct rtmsg *r = NLMSG_DATA(nlh);
+	struct rtmsg *r = nlmsg_data(nlh);
+	struct nlattr *attrs[RTA_MAX+1];
+	int err;
 
 	if (!capable(CAP_NET_ADMIN))
 		return -EPERM;
@@ -526,22 +525,24 @@ static int dn_fib_rtm_delroute(struct sk_buff *skb, struct nlmsghdr *nlh, void *
 	if (!net_eq(net, &init_net))
 		return -EINVAL;
 
-	if (dn_fib_check_attr(r, rta))
-		return -EINVAL;
+	err = nlmsg_parse(nlh, sizeof(*r), attrs, RTA_MAX, rtm_dn_policy);
+	if (err < 0)
+		return err;
 
-	tb = dn_fib_get_table(rtm_get_table(rta, r->rtm_table), 0);
-	if (tb)
-		return tb->delete(tb, r, (struct dn_kern_rta *)rta, nlh, &NETLINK_CB(skb));
+	tb = dn_fib_get_table(rtm_get_table(attrs, r->rtm_table), 0);
+	if (!tb)
+		return -ESRCH;
 
-	return -ESRCH;
+	return tb->delete(tb, r, attrs, nlh, &NETLINK_CB(skb));
 }
 
 static int dn_fib_rtm_newroute(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
 {
 	struct net *net = sock_net(skb->sk);
 	struct dn_fib_table *tb;
-	struct rtattr **rta = arg;
-	struct rtmsg *r = NLMSG_DATA(nlh);
+	struct rtmsg *r = nlmsg_data(nlh);
+	struct nlattr *attrs[RTA_MAX+1];
+	int err;
 
 	if (!capable(CAP_NET_ADMIN))
 		return -EPERM;
@@ -549,14 +550,15 @@ static int dn_fib_rtm_newroute(struct sk_buff *skb, struct nlmsghdr *nlh, void *
 	if (!net_eq(net, &init_net))
 		return -EINVAL;
 
-	if (dn_fib_check_attr(r, rta))
-		return -EINVAL;
+	err = nlmsg_parse(nlh, sizeof(*r), attrs, RTA_MAX, rtm_dn_policy);
+	if (err < 0)
+		return err;
 
-	tb = dn_fib_get_table(rtm_get_table(rta, r->rtm_table), 1);
-	if (tb)
-		return tb->insert(tb, r, (struct dn_kern_rta *)rta, nlh, &NETLINK_CB(skb));
+	tb = dn_fib_get_table(rtm_get_table(attrs, r->rtm_table), 1);
+	if (!tb)
+		return -ENOBUFS;
 
-	return -ENOBUFS;
+	return tb->insert(tb, r, attrs, nlh, &NETLINK_CB(skb));
 }
 
 static void fib_magic(int cmd, int type, __le16 dst, int dst_len, struct dn_ifaddr *ifa)
@@ -566,10 +568,31 @@ static void fib_magic(int cmd, int type, __le16 dst, int dst_len, struct dn_ifad
 		struct nlmsghdr nlh;
 		struct rtmsg rtm;
 	} req;
-	struct dn_kern_rta rta;
+	struct {
+		struct nlattr hdr;
+		__le16 dst;
+	} dst_attr = {
+		.dst = dst,
+	};
+	struct {
+		struct nlattr hdr;
+		__le16 prefsrc;
+	} prefsrc_attr = {
+		.prefsrc = ifa->ifa_local,
+	};
+	struct {
+		struct nlattr hdr;
+		u32 oif;
+	} oif_attr = {
+		.oif = ifa->ifa_dev->dev->ifindex,
+	};
+	struct nlattr *attrs[RTA_MAX+1] = {
+		[RTA_DST] = (struct nlattr *) &dst_attr,
+		[RTA_PREFSRC] = (struct nlattr * ) &prefsrc_attr,
+		[RTA_OIF] = (struct nlattr *) &oif_attr,
+	};
 
 	memset(&req.rtm, 0, sizeof(req.rtm));
-	memset(&rta, 0, sizeof(rta));
 
 	if (type == RTN_UNICAST)
 		tb = dn_fib_get_table(RT_MIN_TABLE, 1);
@@ -591,14 +614,10 @@ static void fib_magic(int cmd, int type, __le16 dst, int dst_len, struct dn_ifad
 	req.rtm.rtm_scope = (type != RTN_LOCAL ? RT_SCOPE_LINK : RT_SCOPE_HOST);
 	req.rtm.rtm_type = type;
 
-	rta.rta_dst = &dst;
-	rta.rta_prefsrc = &ifa->ifa_local;
-	rta.rta_oif = &ifa->ifa_dev->dev->ifindex;
-
 	if (cmd == RTM_NEWROUTE)
-		tb->insert(tb, &req.rtm, &rta, &req.nlh, NULL);
+		tb->insert(tb, &req.rtm, attrs, &req.nlh, NULL);
 	else
-		tb->delete(tb, &req.rtm, &rta, &req.nlh, NULL);
+		tb->delete(tb, &req.rtm, attrs, &req.nlh, NULL);
 }
 
 static void dn_fib_add_ifaddr(struct dn_ifaddr *ifa)
diff --git a/net/decnet/dn_route.c b/net/decnet/dn_route.c
index 5ac0e15..b4b3508 100644
--- a/net/decnet/dn_route.c
+++ b/net/decnet/dn_route.c
@@ -1619,17 +1619,21 @@ errout:
 static int dn_cache_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh, void *arg)
 {
 	struct net *net = sock_net(in_skb->sk);
-	struct rtattr **rta = arg;
 	struct rtmsg *rtm = nlmsg_data(nlh);
 	struct dn_route *rt = NULL;
 	struct dn_skb_cb *cb;
 	int err;
 	struct sk_buff *skb;
 	struct flowidn fld;
+	struct nlattr *tb[RTA_MAX+1];
 
 	if (!net_eq(net, &init_net))
 		return -EINVAL;
 
+	err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_dn_policy);
+	if (err < 0)
+		return err;
+
 	memset(&fld, 0, sizeof(fld));
 	fld.flowidn_proto = DNPROTO_NSP;
 
@@ -1639,12 +1643,14 @@ static int dn_cache_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh, void
 	skb_reset_mac_header(skb);
 	cb = DN_SKB_CB(skb);
 
-	if (rta[RTA_SRC-1])
-		memcpy(&fld.saddr, RTA_DATA(rta[RTA_SRC-1]), 2);
-	if (rta[RTA_DST-1])
-		memcpy(&fld.daddr, RTA_DATA(rta[RTA_DST-1]), 2);
-	if (rta[RTA_IIF-1])
-		memcpy(&fld.flowidn_iif, RTA_DATA(rta[RTA_IIF-1]), sizeof(int));
+	if (tb[RTA_SRC])
+		fld.saddr = nla_get_le16(tb[RTA_SRC]);
+
+	if (tb[RTA_DST])
+		fld.daddr = nla_get_le16(tb[RTA_DST]);
+
+	if (tb[RTA_IIF])
+		fld.flowidn_iif = nla_get_u32(tb[RTA_IIF]);
 
 	if (fld.flowidn_iif) {
 		struct net_device *dev;
@@ -1669,10 +1675,9 @@ static int dn_cache_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh, void
 		if (!err && -rt->dst.error)
 			err = rt->dst.error;
 	} else {
-		int oif = 0;
-		if (rta[RTA_OIF - 1])
-			memcpy(&oif, RTA_DATA(rta[RTA_OIF - 1]), sizeof(int));
-		fld.flowidn_oif = oif;
+		if (tb[RTA_OIF])
+			fld.flowidn_oif = nla_get_u32(tb[RTA_OIF]);
+
 		err = dn_route_output_key((struct dst_entry **)&rt, &fld, 0);
 	}
 
diff --git a/net/decnet/dn_table.c b/net/decnet/dn_table.c
index 6c2445b..fc42a0a 100644
--- a/net/decnet/dn_table.c
+++ b/net/decnet/dn_table.c
@@ -224,26 +224,27 @@ static struct dn_zone *dn_new_zone(struct dn_hash *table, int z)
 }
 
 
-static int dn_fib_nh_match(struct rtmsg *r, struct nlmsghdr *nlh, struct dn_kern_rta *rta, struct dn_fib_info *fi)
+static int dn_fib_nh_match(struct rtmsg *r, struct nlmsghdr *nlh, struct nlattr *attrs[], struct dn_fib_info *fi)
 {
 	struct rtnexthop *nhp;
 	int nhlen;
 
-	if (rta->rta_priority && *rta->rta_priority != fi->fib_priority)
+	if (attrs[RTA_PRIORITY] &&
+	    nla_get_u32(attrs[RTA_PRIORITY]) != fi->fib_priority)
 		return 1;
 
-	if (rta->rta_oif || rta->rta_gw) {
-		if ((!rta->rta_oif || *rta->rta_oif == fi->fib_nh->nh_oif) &&
-		    (!rta->rta_gw  || memcmp(rta->rta_gw, &fi->fib_nh->nh_gw, 2) == 0))
+	if (attrs[RTA_OIF] || attrs[RTA_GATEWAY]) {
+		if ((!attrs[RTA_OIF] || nla_get_u32(attrs[RTA_OIF]) == fi->fib_nh->nh_oif) &&
+		    (!attrs[RTA_GATEWAY]  || nla_get_le16(attrs[RTA_GATEWAY]) != fi->fib_nh->nh_gw))
 			return 0;
 		return 1;
 	}
 
-	if (rta->rta_mp == NULL)
+	if (!attrs[RTA_MULTIPATH])
 		return 0;
 
-	nhp = RTA_DATA(rta->rta_mp);
-	nhlen = RTA_PAYLOAD(rta->rta_mp);
+	nhp = nla_data(attrs[RTA_MULTIPATH]);
+	nhlen = nla_len(attrs[RTA_MULTIPATH]);
 
 	for_nexthops(fi) {
 		int attrlen = nhlen - sizeof(struct rtnexthop);
@@ -254,7 +255,10 @@ static int dn_fib_nh_match(struct rtmsg *r, struct nlmsghdr *nlh, struct dn_kern
 		if (nhp->rtnh_ifindex && nhp->rtnh_ifindex != nh->nh_oif)
 			return 1;
 		if (attrlen) {
-			gw = dn_fib_get_attr16(RTNH_DATA(nhp), attrlen, RTA_GATEWAY);
+			struct nlattr *gw_attr;
+
+			gw_attr = nla_find((struct nlattr *) (nhp + 1), attrlen, RTA_GATEWAY);
+			gw = gw_attr ? nla_get_le16(gw_attr) : 0;
 
 			if (gw && gw != nh->nh_gw)
 				return 1;
@@ -517,7 +521,8 @@ out:
 	return skb->len;
 }
 
-static int dn_fib_table_insert(struct dn_fib_table *tb, struct rtmsg *r, struct dn_kern_rta *rta, struct nlmsghdr *n, struct netlink_skb_parms *req)
+static int dn_fib_table_insert(struct dn_fib_table *tb, struct rtmsg *r, struct nlattr *attrs[],
+			       struct nlmsghdr *n, struct netlink_skb_parms *req)
 {
 	struct dn_hash *table = (struct dn_hash *)tb->data;
 	struct dn_fib_node *new_f, *f, **fp, **del_fp;
@@ -536,15 +541,14 @@ static int dn_fib_table_insert(struct dn_fib_table *tb, struct rtmsg *r, struct
 		return -ENOBUFS;
 
 	dz_key_0(key);
-	if (rta->rta_dst) {
-		__le16 dst;
-		memcpy(&dst, rta->rta_dst, 2);
+	if (attrs[RTA_DST]) {
+		__le16 dst = nla_get_le16(attrs[RTA_DST]);
 		if (dst & ~DZ_MASK(dz))
 			return -EINVAL;
 		key = dz_key(dst, dz);
 	}
 
-	if ((fi = dn_fib_create_info(r, rta, n, &err)) == NULL)
+	if ((fi = dn_fib_create_info(r, attrs, n, &err)) == NULL)
 		return err;
 
 	if (dz->dz_nent > (dz->dz_divisor << 2) &&
@@ -654,7 +658,8 @@ out:
 }
 
 
-static int dn_fib_table_delete(struct dn_fib_table *tb, struct rtmsg *r, struct dn_kern_rta *rta, struct nlmsghdr *n, struct netlink_skb_parms *req)
+static int dn_fib_table_delete(struct dn_fib_table *tb, struct rtmsg *r, struct nlattr *attrs[],
+			       struct nlmsghdr *n, struct netlink_skb_parms *req)
 {
 	struct dn_hash *table = (struct dn_hash*)tb->data;
 	struct dn_fib_node **fp, **del_fp, *f;
@@ -671,9 +676,8 @@ static int dn_fib_table_delete(struct dn_fib_table *tb, struct rtmsg *r, struct
 		return -ESRCH;
 
 	dz_key_0(key);
-	if (rta->rta_dst) {
-		__le16 dst;
-		memcpy(&dst, rta->rta_dst, 2);
+	if (attrs[RTA_DST]) {
+		__le16 dst = nla_get_le16(attrs[RTA_DST]);
 		if (dst & ~DZ_MASK(dz))
 			return -EINVAL;
 		key = dz_key(dst, dz);
@@ -703,7 +707,7 @@ static int dn_fib_table_delete(struct dn_fib_table *tb, struct rtmsg *r, struct
 				(r->rtm_scope == RT_SCOPE_NOWHERE || f->fn_scope == r->rtm_scope) &&
 				(!r->rtm_protocol ||
 					fi->fib_protocol == r->rtm_protocol) &&
-				dn_fib_nh_match(r, n, rta, fi) == 0)
+				dn_fib_nh_match(r, n, attrs, fi) == 0)
 			del_fp = fp;
 	}
 
-- 
1.7.11.7

Re: [PATCH net-next 1/2] decnet: Parse netlink attributes on our own

[Steven Whitehouse]

Hi,

On Thu, 2013-03-21 at 18:45 +0100, Thomas Graf wrote:
> decnet is the only subsystem left that is relying on the global
> netlink attribute buffer rta_buf. It's horrible design and we
> want to get rid of it.
> 
> This converts all of decnet to do implicit attribute parsing. It
> also gets rid of the error prone struct dn_kern_rta.
> 
> Yes, the fib_magic() stuff is not pretty.
> 
> It's compiled tested but I need someone with appropriate hardware
> to test the patch since I don't have access to it.
> 

You shouldn't need any special hardware to test this. A copy of iproute2
should be enough as you should be able to use that to create an
interface or two and a route between them, etc. Although DECnet routing
works in a different way to ip routing, the Linux implementation tries
to stick fairly closely to the ip way of doing things whenever it can in
order to share infrastructure. Now that ip has diverged a fair bit over
time that isn't quite as true as it was, but there shouldn't be anything
too surprising in there.

If you want to actually pass traffic, then you'll have to set the MAC
address of your ethernet card and use the tools that Chrissie wrote to
do that.

I took a quick look at the patches and I can't spot anything obviously
wrong, but then it is a long time since I last seriously looked at it,
so I could easily have missed something,

Steve.


> Cc: linux-decnet-user@lists.sourceforge.net
> Signed-off-by: Thomas Graf <tgraf@suug.ch>
> ---
>  include/net/dn_fib.h  |  28 ++-----
>  net/decnet/dn_fib.c   | 211 +++++++++++++++++++++++++++-----------------------
>  net/decnet/dn_route.c |  27 ++++---
>  net/decnet/dn_table.c |  42 +++++-----
>  4 files changed, 160 insertions(+), 148 deletions(-)
> 
> diff --git a/include/net/dn_fib.h b/include/net/dn_fib.h
> index 1ee9d4b..74004af 100644
> --- a/include/net/dn_fib.h
> +++ b/include/net/dn_fib.h
> @@ -1,24 +1,9 @@
>  #ifndef _NET_DN_FIB_H
>  #define _NET_DN_FIB_H
>  
> -/* WARNING: The ordering of these elements must match ordering
> - *          of RTA_* rtnetlink attribute numbers.
> - */
> -struct dn_kern_rta {
> -        void            *rta_dst;
> -        void            *rta_src;
> -        int             *rta_iif;
> -        int             *rta_oif;
> -        void            *rta_gw;
> -        u32             *rta_priority;
> -        void            *rta_prefsrc;
> -        struct rtattr   *rta_mx;
> -        struct rtattr   *rta_mp;
> -        unsigned char   *rta_protoinfo;
> -        u32             *rta_flow;
> -        struct rta_cacheinfo *rta_ci;
> -	struct rta_session *rta_sess;
> -};
> +#include <linux/netlink.h>
> +
> +extern const struct nla_policy rtm_dn_policy[];
>  
>  struct dn_fib_res {
>  	struct fib_rule *r;
> @@ -93,10 +78,10 @@ struct dn_fib_table {
>  	u32 n;
>  
>  	int (*insert)(struct dn_fib_table *t, struct rtmsg *r, 
> -			struct dn_kern_rta *rta, struct nlmsghdr *n, 
> +			struct nlattr *attrs[], struct nlmsghdr *n,
>  			struct netlink_skb_parms *req);
>  	int (*delete)(struct dn_fib_table *t, struct rtmsg *r,
> -			struct dn_kern_rta *rta, struct nlmsghdr *n,
> +			struct nlattr *attrs[], struct nlmsghdr *n,
>  			struct netlink_skb_parms *req);
>  	int (*lookup)(struct dn_fib_table *t, const struct flowidn *fld,
>  			struct dn_fib_res *res);
> @@ -116,13 +101,12 @@ extern void dn_fib_cleanup(void);
>  extern int dn_fib_ioctl(struct socket *sock, unsigned int cmd, 
>  			unsigned long arg);
>  extern struct dn_fib_info *dn_fib_create_info(const struct rtmsg *r, 
> -				struct dn_kern_rta *rta, 
> +				struct nlattr *attrs[],
>  				const struct nlmsghdr *nlh, int *errp);
>  extern int dn_fib_semantic_match(int type, struct dn_fib_info *fi, 
>  			const struct flowidn *fld,
>  			struct dn_fib_res *res);
>  extern void dn_fib_release_info(struct dn_fib_info *fi);
> -extern __le16 dn_fib_get_attr16(struct rtattr *attr, int attrlen, int type);
>  extern void dn_fib_flush(void);
>  extern void dn_fib_select_multipath(const struct flowidn *fld,
>  					struct dn_fib_res *res);
> diff --git a/net/decnet/dn_fib.c b/net/decnet/dn_fib.c
> index e36614e..42a8048 100644
> --- a/net/decnet/dn_fib.c
> +++ b/net/decnet/dn_fib.c
> @@ -145,22 +145,10 @@ static inline struct dn_fib_info *dn_fib_find_info(const struct dn_fib_info *nfi
>  	return NULL;
>  }
>  
> -__le16 dn_fib_get_attr16(struct rtattr *attr, int attrlen, int type)
> +static int dn_fib_count_nhs(const struct nlattr *attr)
>  {
> -	while(RTA_OK(attr,attrlen)) {
> -		if (attr->rta_type == type)
> -			return *(__le16*)RTA_DATA(attr);
> -		attr = RTA_NEXT(attr, attrlen);
> -	}
> -
> -	return 0;
> -}
> -
> -static int dn_fib_count_nhs(struct rtattr *rta)
> -{
> -	int nhs = 0;
> -	struct rtnexthop *nhp = RTA_DATA(rta);
> -	int nhlen = RTA_PAYLOAD(rta);
> +	struct rtnexthop *nhp = nla_data(attr);
> +	int nhs = 0, nhlen = nla_len(attr);
>  
>  	while(nhlen >= (int)sizeof(struct rtnexthop)) {
>  		if ((nhlen -= nhp->rtnh_len) < 0)
> @@ -172,10 +160,11 @@ static int dn_fib_count_nhs(struct rtattr *rta)
>  	return nhs;
>  }
>  
> -static int dn_fib_get_nhs(struct dn_fib_info *fi, const struct rtattr *rta, const struct rtmsg *r)
> +static int dn_fib_get_nhs(struct dn_fib_info *fi, const struct nlattr *attr,
> +			  const struct rtmsg *r)
>  {
> -	struct rtnexthop *nhp = RTA_DATA(rta);
> -	int nhlen = RTA_PAYLOAD(rta);
> +	struct rtnexthop *nhp = nla_data(attr);
> +	int nhlen = nla_len(attr);
>  
>  	change_nexthops(fi) {
>  		int attrlen = nhlen - sizeof(struct rtnexthop);
> @@ -187,7 +176,10 @@ static int dn_fib_get_nhs(struct dn_fib_info *fi, const struct rtattr *rta, cons
>  		nh->nh_weight = nhp->rtnh_hops + 1;
>  
>  		if (attrlen) {
> -			nh->nh_gw = dn_fib_get_attr16(RTNH_DATA(nhp), attrlen, RTA_GATEWAY);
> +			struct nlattr *gw_attr;
> +
> +			gw_attr = nla_find((struct nlattr *) (nhp + 1), attrlen, RTA_GATEWAY);
> +			nh->nh_gw = gw_attr ? nla_get_le16(gw_attr) : 0;
>  		}
>  		nhp = RTNH_NEXT(nhp);
>  	} endfor_nexthops(fi);
> @@ -268,7 +260,8 @@ out:
>  }
>  
> 
> -struct dn_fib_info *dn_fib_create_info(const struct rtmsg *r, struct dn_kern_rta *rta, const struct nlmsghdr *nlh, int *errp)
> +struct dn_fib_info *dn_fib_create_info(const struct rtmsg *r, struct nlattr *attrs[],
> +				       const struct nlmsghdr *nlh, int *errp)
>  {
>  	int err;
>  	struct dn_fib_info *fi = NULL;
> @@ -281,11 +274,9 @@ struct dn_fib_info *dn_fib_create_info(const struct rtmsg *r, struct dn_kern_rta
>  	if (dn_fib_props[r->rtm_type].scope > r->rtm_scope)
>  		goto err_inval;
>  
> -	if (rta->rta_mp) {
> -		nhs = dn_fib_count_nhs(rta->rta_mp);
> -		if (nhs == 0)
> -			goto err_inval;
> -	}
> +	if (attrs[RTA_MULTIPATH] &&
> +	    (nhs = dn_fib_count_nhs(attrs[RTA_MULTIPATH])) == 0)
> +		goto err_inval;
>  
>  	fi = kzalloc(sizeof(*fi)+nhs*sizeof(struct dn_fib_nh), GFP_KERNEL);
>  	err = -ENOBUFS;
> @@ -295,53 +286,65 @@ struct dn_fib_info *dn_fib_create_info(const struct rtmsg *r, struct dn_kern_rta
>  	fi->fib_protocol = r->rtm_protocol;
>  	fi->fib_nhs = nhs;
>  	fi->fib_flags = r->rtm_flags;
> -	if (rta->rta_priority)
> -		fi->fib_priority = *rta->rta_priority;
> -	if (rta->rta_mx) {
> -		int attrlen = RTA_PAYLOAD(rta->rta_mx);
> -		struct rtattr *attr = RTA_DATA(rta->rta_mx);
>  
> -		while(RTA_OK(attr, attrlen)) {
> -			unsigned int flavour = attr->rta_type;
> +	if (attrs[RTA_PRIORITY])
> +		fi->fib_priority = nla_get_u32(attrs[RTA_PRIORITY]);
> +
> +	if (attrs[RTA_METRICS]) {
> +		struct nlattr *attr;
> +		int rem;
>  
> -			if (flavour) {
> -				if (flavour > RTAX_MAX)
> +		nla_for_each_nested(attr, attrs[RTA_METRICS], rem) {
> +			int type = nla_type(attr);
> +
> +			if (type) {
> +				if (type > RTAX_MAX || nla_len(attr) < 4)
>  					goto err_inval;
> -				fi->fib_metrics[flavour-1] = *(unsigned int *)RTA_DATA(attr);
> +
> +				fi->fib_metrics[type-1] = nla_get_u32(attr);
>  			}
> -			attr = RTA_NEXT(attr, attrlen);
>  		}
>  	}
> -	if (rta->rta_prefsrc)
> -		memcpy(&fi->fib_prefsrc, rta->rta_prefsrc, 2);
>  
> -	if (rta->rta_mp) {
> -		if ((err = dn_fib_get_nhs(fi, rta->rta_mp, r)) != 0)
> +	if (attrs[RTA_PREFSRC])
> +		fi->fib_prefsrc = nla_get_le16(attrs[RTA_PREFSRC]);
> +
> +	if (attrs[RTA_MULTIPATH]) {
> +		if ((err = dn_fib_get_nhs(fi, attrs[RTA_MULTIPATH], r)) != 0)
>  			goto failure;
> -		if (rta->rta_oif && fi->fib_nh->nh_oif != *rta->rta_oif)
> +
> +		if (attrs[RTA_OIF] &&
> +		    fi->fib_nh->nh_oif != nla_get_u32(attrs[RTA_OIF]))
>  			goto err_inval;
> -		if (rta->rta_gw && memcmp(&fi->fib_nh->nh_gw, rta->rta_gw, 2))
> +
> +		if (attrs[RTA_GATEWAY] &&
> +		    fi->fib_nh->nh_gw != nla_get_le16(attrs[RTA_GATEWAY]))
>  			goto err_inval;
>  	} else {
>  		struct dn_fib_nh *nh = fi->fib_nh;
> -		if (rta->rta_oif)
> -			nh->nh_oif = *rta->rta_oif;
> -		if (rta->rta_gw)
> -			memcpy(&nh->nh_gw, rta->rta_gw, 2);
> +
> +		if (attrs[RTA_OIF])
> +			nh->nh_oif = nla_get_u32(attrs[RTA_OIF]);
> +
> +		if (attrs[RTA_GATEWAY])
> +			nh->nh_gw = nla_get_le16(attrs[RTA_GATEWAY]);
> +
>  		nh->nh_flags = r->rtm_flags;
>  		nh->nh_weight = 1;
>  	}
>  
>  	if (r->rtm_type == RTN_NAT) {
> -		if (rta->rta_gw == NULL || nhs != 1 || rta->rta_oif)
> +		if (!attrs[RTA_GATEWAY] || nhs != 1 || attrs[RTA_OIF])
>  			goto err_inval;
> -		memcpy(&fi->fib_nh->nh_gw, rta->rta_gw, 2);
> +
> +		fi->fib_nh->nh_gw = nla_get_le16(attrs[RTA_GATEWAY]);
>  		goto link_it;
>  	}
>  
>  	if (dn_fib_props[r->rtm_type].error) {
> -		if (rta->rta_gw || rta->rta_oif || rta->rta_mp)
> +		if (attrs[RTA_GATEWAY] || attrs[RTA_OIF] || attrs[RTA_MULTIPATH])
>  			goto err_inval;
> +
>  		goto link_it;
>  	}
>  
> @@ -367,8 +370,8 @@ struct dn_fib_info *dn_fib_create_info(const struct rtmsg *r, struct dn_kern_rta
>  	}
>  
>  	if (fi->fib_prefsrc) {
> -		if (r->rtm_type != RTN_LOCAL || rta->rta_dst == NULL ||
> -		    memcmp(&fi->fib_prefsrc, rta->rta_dst, 2))
> +		if (r->rtm_type != RTN_LOCAL || !attrs[RTA_DST] ||
> +		    fi->fib_prefsrc != nla_get_le16(attrs[RTA_DST]))
>  			if (dnet_addr_type(fi->fib_prefsrc) != RTN_LOCAL)
>  				goto err_inval;
>  	}
> @@ -486,29 +489,24 @@ void dn_fib_select_multipath(const struct flowidn *fld, struct dn_fib_res *res)
>  	spin_unlock_bh(&dn_fib_multipath_lock);
>  }
>  
> +const struct nla_policy rtm_dn_policy[RTA_MAX + 1] = {
> +	[RTA_DST]		= { .type = NLA_U16 },
> +	[RTA_SRC]		= { .type = NLA_U16 },
> +	[RTA_IIF]		= { .type = NLA_U32 },
> +	[RTA_OIF]		= { .type = NLA_U32 },
> +	[RTA_GATEWAY]		= { .type = NLA_U16 },
> +	[RTA_PRIORITY]		= { .type = NLA_U32 },
> +	[RTA_PREFSRC]		= { .type = NLA_U16 },
> +	[RTA_METRICS]		= { .type = NLA_NESTED },
> +	[RTA_MULTIPATH]		= { .type = NLA_NESTED },
> +	[RTA_TABLE]		= { .type = NLA_U32 },
> +	[RTA_MARK]		= { .type = NLA_U32 },
> +};
>  
> -static int dn_fib_check_attr(struct rtmsg *r, struct rtattr **rta)
> -{
> -	int i;
> -
> -	for(i = 1; i <= RTA_MAX; i++) {
> -		struct rtattr *attr = rta[i-1];
> -		if (attr) {
> -			if (RTA_PAYLOAD(attr) < 4 && RTA_PAYLOAD(attr) != 2)
> -				return -EINVAL;
> -			if (i != RTA_MULTIPATH && i != RTA_METRICS &&
> -			    i != RTA_TABLE)
> -				rta[i-1] = (struct rtattr *)RTA_DATA(attr);
> -		}
> -	}
> -
> -	return 0;
> -}
> -
> -static inline u32 rtm_get_table(struct rtattr **rta, u8 table)
> +static inline u32 rtm_get_table(struct nlattr *attrs[], u8 table)
>  {
> -	if (rta[RTA_TABLE - 1])
> -		table = nla_get_u32((struct nlattr *) rta[RTA_TABLE - 1]);
> +	if (attrs[RTA_TABLE])
> +		table = nla_get_u32(attrs[RTA_TABLE]);
>  
>  	return table;
>  }
> @@ -517,8 +515,9 @@ static int dn_fib_rtm_delroute(struct sk_buff *skb, struct nlmsghdr *nlh, void *
>  {
>  	struct net *net = sock_net(skb->sk);
>  	struct dn_fib_table *tb;
> -	struct rtattr **rta = arg;
> -	struct rtmsg *r = NLMSG_DATA(nlh);
> +	struct rtmsg *r = nlmsg_data(nlh);
> +	struct nlattr *attrs[RTA_MAX+1];
> +	int err;
>  
>  	if (!capable(CAP_NET_ADMIN))
>  		return -EPERM;
> @@ -526,22 +525,24 @@ static int dn_fib_rtm_delroute(struct sk_buff *skb, struct nlmsghdr *nlh, void *
>  	if (!net_eq(net, &init_net))
>  		return -EINVAL;
>  
> -	if (dn_fib_check_attr(r, rta))
> -		return -EINVAL;
> +	err = nlmsg_parse(nlh, sizeof(*r), attrs, RTA_MAX, rtm_dn_policy);
> +	if (err < 0)
> +		return err;
>  
> -	tb = dn_fib_get_table(rtm_get_table(rta, r->rtm_table), 0);
> -	if (tb)
> -		return tb->delete(tb, r, (struct dn_kern_rta *)rta, nlh, &NETLINK_CB(skb));
> +	tb = dn_fib_get_table(rtm_get_table(attrs, r->rtm_table), 0);
> +	if (!tb)
> +		return -ESRCH;
>  
> -	return -ESRCH;
> +	return tb->delete(tb, r, attrs, nlh, &NETLINK_CB(skb));
>  }
>  
>  static int dn_fib_rtm_newroute(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
>  {
>  	struct net *net = sock_net(skb->sk);
>  	struct dn_fib_table *tb;
> -	struct rtattr **rta = arg;
> -	struct rtmsg *r = NLMSG_DATA(nlh);
> +	struct rtmsg *r = nlmsg_data(nlh);
> +	struct nlattr *attrs[RTA_MAX+1];
> +	int err;
>  
>  	if (!capable(CAP_NET_ADMIN))
>  		return -EPERM;
> @@ -549,14 +550,15 @@ static int dn_fib_rtm_newroute(struct sk_buff *skb, struct nlmsghdr *nlh, void *
>  	if (!net_eq(net, &init_net))
>  		return -EINVAL;
>  
> -	if (dn_fib_check_attr(r, rta))
> -		return -EINVAL;
> +	err = nlmsg_parse(nlh, sizeof(*r), attrs, RTA_MAX, rtm_dn_policy);
> +	if (err < 0)
> +		return err;
>  
> -	tb = dn_fib_get_table(rtm_get_table(rta, r->rtm_table), 1);
> -	if (tb)
> -		return tb->insert(tb, r, (struct dn_kern_rta *)rta, nlh, &NETLINK_CB(skb));
> +	tb = dn_fib_get_table(rtm_get_table(attrs, r->rtm_table), 1);
> +	if (!tb)
> +		return -ENOBUFS;
>  
> -	return -ENOBUFS;
> +	return tb->insert(tb, r, attrs, nlh, &NETLINK_CB(skb));
>  }
>  
>  static void fib_magic(int cmd, int type, __le16 dst, int dst_len, struct dn_ifaddr *ifa)
> @@ -566,10 +568,31 @@ static void fib_magic(int cmd, int type, __le16 dst, int dst_len, struct dn_ifad
>  		struct nlmsghdr nlh;
>  		struct rtmsg rtm;
>  	} req;
> -	struct dn_kern_rta rta;
> +	struct {
> +		struct nlattr hdr;
> +		__le16 dst;
> +	} dst_attr = {
> +		.dst = dst,
> +	};
> +	struct {
> +		struct nlattr hdr;
> +		__le16 prefsrc;
> +	} prefsrc_attr = {
> +		.prefsrc = ifa->ifa_local,
> +	};
> +	struct {
> +		struct nlattr hdr;
> +		u32 oif;
> +	} oif_attr = {
> +		.oif = ifa->ifa_dev->dev->ifindex,
> +	};
> +	struct nlattr *attrs[RTA_MAX+1] = {
> +		[RTA_DST] = (struct nlattr *) &dst_attr,
> +		[RTA_PREFSRC] = (struct nlattr * ) &prefsrc_attr,
> +		[RTA_OIF] = (struct nlattr *) &oif_attr,
> +	};
>  
>  	memset(&req.rtm, 0, sizeof(req.rtm));
> -	memset(&rta, 0, sizeof(rta));
>  
>  	if (type == RTN_UNICAST)
>  		tb = dn_fib_get_table(RT_MIN_TABLE, 1);
> @@ -591,14 +614,10 @@ static void fib_magic(int cmd, int type, __le16 dst, int dst_len, struct dn_ifad
>  	req.rtm.rtm_scope = (type != RTN_LOCAL ? RT_SCOPE_LINK : RT_SCOPE_HOST);
>  	req.rtm.rtm_type = type;
>  
> -	rta.rta_dst = &dst;
> -	rta.rta_prefsrc = &ifa->ifa_local;
> -	rta.rta_oif = &ifa->ifa_dev->dev->ifindex;
> -
>  	if (cmd == RTM_NEWROUTE)
> -		tb->insert(tb, &req.rtm, &rta, &req.nlh, NULL);
> +		tb->insert(tb, &req.rtm, attrs, &req.nlh, NULL);
>  	else
> -		tb->delete(tb, &req.rtm, &rta, &req.nlh, NULL);
> +		tb->delete(tb, &req.rtm, attrs, &req.nlh, NULL);
>  }
>  
>  static void dn_fib_add_ifaddr(struct dn_ifaddr *ifa)
> diff --git a/net/decnet/dn_route.c b/net/decnet/dn_route.c
> index 5ac0e15..b4b3508 100644
> --- a/net/decnet/dn_route.c
> +++ b/net/decnet/dn_route.c
> @@ -1619,17 +1619,21 @@ errout:
>  static int dn_cache_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh, void *arg)
>  {
>  	struct net *net = sock_net(in_skb->sk);
> -	struct rtattr **rta = arg;
>  	struct rtmsg *rtm = nlmsg_data(nlh);
>  	struct dn_route *rt = NULL;
>  	struct dn_skb_cb *cb;
>  	int err;
>  	struct sk_buff *skb;
>  	struct flowidn fld;
> +	struct nlattr *tb[RTA_MAX+1];
>  
>  	if (!net_eq(net, &init_net))
>  		return -EINVAL;
>  
> +	err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_dn_policy);
> +	if (err < 0)
> +		return err;
> +
>  	memset(&fld, 0, sizeof(fld));
>  	fld.flowidn_proto = DNPROTO_NSP;
>  
> @@ -1639,12 +1643,14 @@ static int dn_cache_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh, void
>  	skb_reset_mac_header(skb);
>  	cb = DN_SKB_CB(skb);
>  
> -	if (rta[RTA_SRC-1])
> -		memcpy(&fld.saddr, RTA_DATA(rta[RTA_SRC-1]), 2);
> -	if (rta[RTA_DST-1])
> -		memcpy(&fld.daddr, RTA_DATA(rta[RTA_DST-1]), 2);
> -	if (rta[RTA_IIF-1])
> -		memcpy(&fld.flowidn_iif, RTA_DATA(rta[RTA_IIF-1]), sizeof(int));
> +	if (tb[RTA_SRC])
> +		fld.saddr = nla_get_le16(tb[RTA_SRC]);
> +
> +	if (tb[RTA_DST])
> +		fld.daddr = nla_get_le16(tb[RTA_DST]);
> +
> +	if (tb[RTA_IIF])
> +		fld.flowidn_iif = nla_get_u32(tb[RTA_IIF]);
>  
>  	if (fld.flowidn_iif) {
>  		struct net_device *dev;
> @@ -1669,10 +1675,9 @@ static int dn_cache_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh, void
>  		if (!err && -rt->dst.error)
>  			err = rt->dst.error;
>  	} else {
> -		int oif = 0;
> -		if (rta[RTA_OIF - 1])
> -			memcpy(&oif, RTA_DATA(rta[RTA_OIF - 1]), sizeof(int));
> -		fld.flowidn_oif = oif;
> +		if (tb[RTA_OIF])
> +			fld.flowidn_oif = nla_get_u32(tb[RTA_OIF]);
> +
>  		err = dn_route_output_key((struct dst_entry **)&rt, &fld, 0);
>  	}
>  
> diff --git a/net/decnet/dn_table.c b/net/decnet/dn_table.c
> index 6c2445b..fc42a0a 100644
> --- a/net/decnet/dn_table.c
> +++ b/net/decnet/dn_table.c
> @@ -224,26 +224,27 @@ static struct dn_zone *dn_new_zone(struct dn_hash *table, int z)
>  }
>  
> 
> -static int dn_fib_nh_match(struct rtmsg *r, struct nlmsghdr *nlh, struct dn_kern_rta *rta, struct dn_fib_info *fi)
> +static int dn_fib_nh_match(struct rtmsg *r, struct nlmsghdr *nlh, struct nlattr *attrs[], struct dn_fib_info *fi)
>  {
>  	struct rtnexthop *nhp;
>  	int nhlen;
>  
> -	if (rta->rta_priority && *rta->rta_priority != fi->fib_priority)
> +	if (attrs[RTA_PRIORITY] &&
> +	    nla_get_u32(attrs[RTA_PRIORITY]) != fi->fib_priority)
>  		return 1;
>  
> -	if (rta->rta_oif || rta->rta_gw) {
> -		if ((!rta->rta_oif || *rta->rta_oif == fi->fib_nh->nh_oif) &&
> -		    (!rta->rta_gw  || memcmp(rta->rta_gw, &fi->fib_nh->nh_gw, 2) == 0))
> +	if (attrs[RTA_OIF] || attrs[RTA_GATEWAY]) {
> +		if ((!attrs[RTA_OIF] || nla_get_u32(attrs[RTA_OIF]) == fi->fib_nh->nh_oif) &&
> +		    (!attrs[RTA_GATEWAY]  || nla_get_le16(attrs[RTA_GATEWAY]) != fi->fib_nh->nh_gw))
>  			return 0;
>  		return 1;
>  	}
>  
> -	if (rta->rta_mp == NULL)
> +	if (!attrs[RTA_MULTIPATH])
>  		return 0;
>  
> -	nhp = RTA_DATA(rta->rta_mp);
> -	nhlen = RTA_PAYLOAD(rta->rta_mp);
> +	nhp = nla_data(attrs[RTA_MULTIPATH]);
> +	nhlen = nla_len(attrs[RTA_MULTIPATH]);
>  
>  	for_nexthops(fi) {
>  		int attrlen = nhlen - sizeof(struct rtnexthop);
> @@ -254,7 +255,10 @@ static int dn_fib_nh_match(struct rtmsg *r, struct nlmsghdr *nlh, struct dn_kern
>  		if (nhp->rtnh_ifindex && nhp->rtnh_ifindex != nh->nh_oif)
>  			return 1;
>  		if (attrlen) {
> -			gw = dn_fib_get_attr16(RTNH_DATA(nhp), attrlen, RTA_GATEWAY);
> +			struct nlattr *gw_attr;
> +
> +			gw_attr = nla_find((struct nlattr *) (nhp + 1), attrlen, RTA_GATEWAY);
> +			gw = gw_attr ? nla_get_le16(gw_attr) : 0;
>  
>  			if (gw && gw != nh->nh_gw)
>  				return 1;
> @@ -517,7 +521,8 @@ out:
>  	return skb->len;
>  }
>  
> -static int dn_fib_table_insert(struct dn_fib_table *tb, struct rtmsg *r, struct dn_kern_rta *rta, struct nlmsghdr *n, struct netlink_skb_parms *req)
> +static int dn_fib_table_insert(struct dn_fib_table *tb, struct rtmsg *r, struct nlattr *attrs[],
> +			       struct nlmsghdr *n, struct netlink_skb_parms *req)
>  {
>  	struct dn_hash *table = (struct dn_hash *)tb->data;
>  	struct dn_fib_node *new_f, *f, **fp, **del_fp;
> @@ -536,15 +541,14 @@ static int dn_fib_table_insert(struct dn_fib_table *tb, struct rtmsg *r, struct
>  		return -ENOBUFS;
>  
>  	dz_key_0(key);
> -	if (rta->rta_dst) {
> -		__le16 dst;
> -		memcpy(&dst, rta->rta_dst, 2);
> +	if (attrs[RTA_DST]) {
> +		__le16 dst = nla_get_le16(attrs[RTA_DST]);
>  		if (dst & ~DZ_MASK(dz))
>  			return -EINVAL;
>  		key = dz_key(dst, dz);
>  	}
>  
> -	if ((fi = dn_fib_create_info(r, rta, n, &err)) == NULL)
> +	if ((fi = dn_fib_create_info(r, attrs, n, &err)) == NULL)
>  		return err;
>  
>  	if (dz->dz_nent > (dz->dz_divisor << 2) &&
> @@ -654,7 +658,8 @@ out:
>  }
>  
> 
> -static int dn_fib_table_delete(struct dn_fib_table *tb, struct rtmsg *r, struct dn_kern_rta *rta, struct nlmsghdr *n, struct netlink_skb_parms *req)
> +static int dn_fib_table_delete(struct dn_fib_table *tb, struct rtmsg *r, struct nlattr *attrs[],
> +			       struct nlmsghdr *n, struct netlink_skb_parms *req)
>  {
>  	struct dn_hash *table = (struct dn_hash*)tb->data;
>  	struct dn_fib_node **fp, **del_fp, *f;
> @@ -671,9 +676,8 @@ static int dn_fib_table_delete(struct dn_fib_table *tb, struct rtmsg *r, struct
>  		return -ESRCH;
>  
>  	dz_key_0(key);
> -	if (rta->rta_dst) {
> -		__le16 dst;
> -		memcpy(&dst, rta->rta_dst, 2);
> +	if (attrs[RTA_DST]) {
> +		__le16 dst = nla_get_le16(attrs[RTA_DST]);
>  		if (dst & ~DZ_MASK(dz))
>  			return -EINVAL;
>  		key = dz_key(dst, dz);
> @@ -703,7 +707,7 @@ static int dn_fib_table_delete(struct dn_fib_table *tb, struct rtmsg *r, struct
>  				(r->rtm_scope == RT_SCOPE_NOWHERE || f->fn_scope == r->rtm_scope) &&
>  				(!r->rtm_protocol ||
>  					fi->fib_protocol == r->rtm_protocol) &&
> -				dn_fib_nh_match(r, n, rta, fi) == 0)
> +				dn_fib_nh_match(r, n, attrs, fi) == 0)
>  			del_fp = fp;
>  	}
>  

Re: [PATCH net-next 1/2] decnet: Parse netlink attributes on our own

[Thomas Graf]

On 03/21/13 at 06:04pm, Steven Whitehouse wrote:
> You shouldn't need any special hardware to test this. A copy of iproute2
> should be enough as you should be able to use that to create an
> interface or two and a route between them, etc. Although DECnet routing
> works in a different way to ip routing, the Linux implementation tries
> to stick fairly closely to the ip way of doing things whenever it can in
> order to share infrastructure. Now that ip has diverged a fair bit over
> time that isn't quite as true as it was, but there shouldn't be anything
> too surprising in there.

Alright, I did some basic testing with iproute2. I do not claim
to understand what I did but I ran the following:

$ ip -f dnet route add 1.661 dev em1
$ ip -f dnet route list
1.661 dev em1  scope link

$ ip -f dnet neigh add 6.662 dev em1
$ ip -f dnet neigh list
6.662 dev em1 lladdr aa:00:04:00:96:1a PERMANENT

$ ip -f dnet addr add 1.111 dev em1
$ ip -f dnet addr list
2: em1: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc pfifo_fast state DOWN qlen 1000
    dnet 1.111/16 scope global em1

Re: [PATCH net-next 1/2] decnet: Parse netlink attributes on our own

[Steven Whitehouse]

Hi,

On Fri, 2013-03-22 at 14:27 +0000, Thomas Graf wrote:
> On 03/21/13 at 06:04pm, Steven Whitehouse wrote:
> > You shouldn't need any special hardware to test this. A copy of iproute2
> > should be enough as you should be able to use that to create an
> > interface or two and a route between them, etc. Although DECnet routing
> > works in a different way to ip routing, the Linux implementation tries
> > to stick fairly closely to the ip way of doing things whenever it can in
> > order to share infrastructure. Now that ip has diverged a fair bit over
> > time that isn't quite as true as it was, but there shouldn't be anything
> > too surprising in there.
> 
> Alright, I did some basic testing with iproute2. I do not claim
> to understand what I did but I ran the following:
> 
> $ ip -f dnet route add 1.661 dev em1
> $ ip -f dnet route list
> 1.661 dev em1  scope link
> 
> $ ip -f dnet neigh add 6.662 dev em1
> $ ip -f dnet neigh list
> 6.662 dev em1 lladdr aa:00:04:00:96:1a PERMANENT
> 
> $ ip -f dnet addr add 1.111 dev em1
> $ ip -f dnet addr list
> 2: em1: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc pfifo_fast state DOWN qlen 1000
>     dnet 1.111/16 scope global em1

That looks sane to me. The only thing I could think of to add to that
list would be to use ip route get to do a lookup, but otherwise, that
seems to cover everything pretty much,

Steve.

Re: [PATCH net-next 1/2] decnet: Parse netlink attributes on our own

[David Miller]

From: Thomas Graf <tgraf@suug.ch>
Date: Fri, 22 Mar 2013 14:27:35 +0000

> On 03/21/13 at 06:04pm, Steven Whitehouse wrote:
>> You shouldn't need any special hardware to test this. A copy of iproute2
>> should be enough as you should be able to use that to create an
>> interface or two and a route between them, etc. Although DECnet routing
>> works in a different way to ip routing, the Linux implementation tries
>> to stick fairly closely to the ip way of doing things whenever it can in
>> order to share infrastructure. Now that ip has diverged a fair bit over
>> time that isn't quite as true as it was, but there shouldn't be anything
>> too surprising in there.
> 
> Alright, I did some basic testing with iproute2. I do not claim
> to understand what I did but I ran the following:
> 
> $ ip -f dnet route add 1.661 dev em1
> $ ip -f dnet route list
> 1.661 dev em1  scope link
> 
> $ ip -f dnet neigh add 6.662 dev em1
> $ ip -f dnet neigh list
> 6.662 dev em1 lladdr aa:00:04:00:96:1a PERMANENT
> 
> $ ip -f dnet addr add 1.111 dev em1
> $ ip -f dnet addr list
> 2: em1: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc pfifo_fast state DOWN qlen 1000
>     dnet 1.111/16 scope global em1

That's good enough for me, both patches applied, thanks Thomas!

[PATCH net-next] decnet: Move rtm_dn_policy to dn_route to make it available if !CONFIG_DECNET_ROUTER

[Thomas Graf]

Otherwise build fails with CONFIG_DECNET && !CONFIG_DECNET_ROUTER

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Thomas Graf <tgraf@suug.ch>
---
 net/decnet/dn_fib.c   | 14 --------------
 net/decnet/dn_route.c | 14 ++++++++++++++
 2 files changed, 14 insertions(+), 14 deletions(-)

diff --git a/net/decnet/dn_fib.c b/net/decnet/dn_fib.c
index f093059..57dc159 100644
--- a/net/decnet/dn_fib.c
+++ b/net/decnet/dn_fib.c
@@ -489,20 +489,6 @@ void dn_fib_select_multipath(const struct flowidn *fld, struct dn_fib_res *res)
 	spin_unlock_bh(&dn_fib_multipath_lock);
 }
 
-const struct nla_policy rtm_dn_policy[RTA_MAX + 1] = {
-	[RTA_DST]		= { .type = NLA_U16 },
-	[RTA_SRC]		= { .type = NLA_U16 },
-	[RTA_IIF]		= { .type = NLA_U32 },
-	[RTA_OIF]		= { .type = NLA_U32 },
-	[RTA_GATEWAY]		= { .type = NLA_U16 },
-	[RTA_PRIORITY]		= { .type = NLA_U32 },
-	[RTA_PREFSRC]		= { .type = NLA_U16 },
-	[RTA_METRICS]		= { .type = NLA_NESTED },
-	[RTA_MULTIPATH]		= { .type = NLA_NESTED },
-	[RTA_TABLE]		= { .type = NLA_U32 },
-	[RTA_MARK]		= { .type = NLA_U32 },
-};
-
 static inline u32 rtm_get_table(struct nlattr *attrs[], u8 table)
 {
 	if (attrs[RTA_TABLE])
diff --git a/net/decnet/dn_route.c b/net/decnet/dn_route.c
index 5904429..fe32388 100644
--- a/net/decnet/dn_route.c
+++ b/net/decnet/dn_route.c
@@ -1613,6 +1613,20 @@ errout:
 	return -EMSGSIZE;
 }
 
+const struct nla_policy rtm_dn_policy[RTA_MAX + 1] = {
+	[RTA_DST]		= { .type = NLA_U16 },
+	[RTA_SRC]		= { .type = NLA_U16 },
+	[RTA_IIF]		= { .type = NLA_U32 },
+	[RTA_OIF]		= { .type = NLA_U32 },
+	[RTA_GATEWAY]		= { .type = NLA_U16 },
+	[RTA_PRIORITY]		= { .type = NLA_U32 },
+	[RTA_PREFSRC]		= { .type = NLA_U16 },
+	[RTA_METRICS]		= { .type = NLA_NESTED },
+	[RTA_MULTIPATH]		= { .type = NLA_NESTED },
+	[RTA_TABLE]		= { .type = NLA_U32 },
+	[RTA_MARK]		= { .type = NLA_U32 },
+};
+
 /*
  * This is called by both endnodes and routers now.
  */

Re: [PATCH net-next] decnet: Move rtm_dn_policy to dn_route to make it available if !CONFIG_DECNET_ROUTER

[David Miller]

From: Thomas Graf <tgraf@suug.ch>
Date: Fri, 22 Mar 2013 16:50:29 +0000

> Otherwise build fails with CONFIG_DECNET && !CONFIG_DECNET_ROUTER
> 
> Reported-by: kbuild test robot <fengguang.wu@intel.com>
> Signed-off-by: Thomas Graf <tgraf@suug.ch>

Applied, thanks Thomas.

[PATCH net-next 2/2] rtnetlink: Remove passing of attributes into rtnl_doit functions

[Thomas Graf]

With decnet converted, we can finally get rid of rta_buf and its
computations around it. It also gets rid of the minimal header
length verification since all message handlers do that explicitly
anyway.

Signed-off-by: Thomas Graf <tgraf@suug.ch>
---
 include/net/rtnetlink.h |  2 +-
 net/bridge/br_mdb.c     |  4 +--
 net/can/gw.c            |  5 ++-
 net/core/fib_rules.c    |  4 +--
 net/core/neighbour.c    |  6 ++--
 net/core/rtnetlink.c    | 82 ++++++-------------------------------------------
 net/dcb/dcbnl.c         |  2 +-
 net/decnet/dn_dev.c     |  4 +--
 net/decnet/dn_fib.c     |  4 +--
 net/decnet/dn_route.c   |  2 +-
 net/ipv4/devinet.c      |  7 ++---
 net/ipv4/fib_frontend.c |  4 +--
 net/ipv4/route.c        |  2 +-
 net/ipv6/addrconf.c     | 10 +++---
 net/ipv6/addrlabel.c    |  6 ++--
 net/ipv6/route.c        |  6 ++--
 net/phonet/pn_netlink.c |  4 +--
 net/sched/act_api.c     |  2 +-
 net/sched/cls_api.c     |  2 +-
 net/sched/sch_api.c     |  6 ++--
 20 files changed, 47 insertions(+), 117 deletions(-)

diff --git a/include/net/rtnetlink.h b/include/net/rtnetlink.h
index 5a15fab..7026648 100644
--- a/include/net/rtnetlink.h
+++ b/include/net/rtnetlink.h
@@ -4,7 +4,7 @@
 #include <linux/rtnetlink.h>
 #include <net/netlink.h>
 
-typedef int (*rtnl_doit_func)(struct sk_buff *, struct nlmsghdr *, void *);
+typedef int (*rtnl_doit_func)(struct sk_buff *, struct nlmsghdr *);
 typedef int (*rtnl_dumpit_func)(struct sk_buff *, struct netlink_callback *);
 typedef u16 (*rtnl_calcit_func)(struct sk_buff *, struct nlmsghdr *);
 
diff --git a/net/bridge/br_mdb.c b/net/bridge/br_mdb.c
index ee79f3f..19942e3 100644
--- a/net/bridge/br_mdb.c
+++ b/net/bridge/br_mdb.c
@@ -382,7 +382,7 @@ static int __br_mdb_add(struct net *net, struct net_bridge *br,
 	return ret;
 }
 
-static int br_mdb_add(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
+static int br_mdb_add(struct sk_buff *skb, struct nlmsghdr *nlh)
 {
 	struct net *net = sock_net(skb->sk);
 	struct br_mdb_entry *entry;
@@ -458,7 +458,7 @@ unlock:
 	return err;
 }
 
-static int br_mdb_del(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
+static int br_mdb_del(struct sk_buff *skb, struct nlmsghdr *nlh)
 {
 	struct net_device *dev;
 	struct br_mdb_entry *entry;
diff --git a/net/can/gw.c b/net/can/gw.c
index 2d117dc..2dc619d 100644
--- a/net/can/gw.c
+++ b/net/can/gw.c
@@ -778,8 +778,7 @@ static int cgw_parse_attr(struct nlmsghdr *nlh, struct cf_mod *mod,
 	return 0;
 }
 
-static int cgw_create_job(struct sk_buff *skb,  struct nlmsghdr *nlh,
-			  void *arg)
+static int cgw_create_job(struct sk_buff *skb,  struct nlmsghdr *nlh)
 {
 	struct rtcanmsg *r;
 	struct cgw_job *gwj;
@@ -868,7 +867,7 @@ static void cgw_remove_all_jobs(void)
 	}
 }
 
-static int cgw_remove_job(struct sk_buff *skb,  struct nlmsghdr *nlh, void *arg)
+static int cgw_remove_job(struct sk_buff *skb,  struct nlmsghdr *nlh)
 {
 	struct cgw_job *gwj = NULL;
 	struct hlist_node *nx;
diff --git a/net/core/fib_rules.c b/net/core/fib_rules.c
index 58a4ba2..d5a9f8e 100644
--- a/net/core/fib_rules.c
+++ b/net/core/fib_rules.c
@@ -266,7 +266,7 @@ errout:
 	return err;
 }
 
-static int fib_nl_newrule(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
+static int fib_nl_newrule(struct sk_buff *skb, struct nlmsghdr* nlh)
 {
 	struct net *net = sock_net(skb->sk);
 	struct fib_rule_hdr *frh = nlmsg_data(nlh);
@@ -415,7 +415,7 @@ errout:
 	return err;
 }
 
-static int fib_nl_delrule(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
+static int fib_nl_delrule(struct sk_buff *skb, struct nlmsghdr* nlh)
 {
 	struct net *net = sock_net(skb->sk);
 	struct fib_rule_hdr *frh = nlmsg_data(nlh);
diff --git a/net/core/neighbour.c b/net/core/neighbour.c
index 3863b8f..c72a646 100644
--- a/net/core/neighbour.c
+++ b/net/core/neighbour.c
@@ -1613,7 +1613,7 @@ int neigh_table_clear(struct neigh_table *tbl)
 }
 EXPORT_SYMBOL(neigh_table_clear);
 
-static int neigh_delete(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
+static int neigh_delete(struct sk_buff *skb, struct nlmsghdr *nlh)
 {
 	struct net *net = sock_net(skb->sk);
 	struct ndmsg *ndm;
@@ -1677,7 +1677,7 @@ out:
 	return err;
 }
 
-static int neigh_add(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
+static int neigh_add(struct sk_buff *skb, struct nlmsghdr *nlh)
 {
 	struct net *net = sock_net(skb->sk);
 	struct ndmsg *ndm;
@@ -1955,7 +1955,7 @@ static const struct nla_policy nl_ntbl_parm_policy[NDTPA_MAX+1] = {
 	[NDTPA_LOCKTIME]		= { .type = NLA_U64 },
 };
 
-static int neightbl_set(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
+static int neightbl_set(struct sk_buff *skb, struct nlmsghdr *nlh)
 {
 	struct net *net = sock_net(skb->sk);
 	struct neigh_table *tbl;
diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index 9a9b99e..751f124 100644
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -515,32 +515,6 @@ out:
 	return err;
 }
 
-static const int rtm_min[RTM_NR_FAMILIES] =
-{
-	[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_NEWRULE)]      = NLMSG_LENGTH(sizeof(struct fib_rule_hdr)),
-	[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_GETMULTICAST)] = NLMSG_LENGTH(sizeof(struct rtgenmsg)),
-	[RTM_FAM(RTM_GETANYCAST)]   = NLMSG_LENGTH(sizeof(struct rtgenmsg)),
-};
-
-static const int rta_max[RTM_NR_FAMILIES] =
-{
-	[RTM_FAM(RTM_NEWLINK)]      = IFLA_MAX,
-	[RTM_FAM(RTM_NEWADDR)]      = IFA_MAX,
-	[RTM_FAM(RTM_NEWROUTE)]     = RTA_MAX,
-	[RTM_FAM(RTM_NEWRULE)]      = FRA_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,
-};
-
 int rtnetlink_send(struct sk_buff *skb, struct net *net, u32 pid, unsigned int group, int echo)
 {
 	struct sock *rtnl = net->rtnl;
@@ -1537,7 +1511,7 @@ errout:
 	return err;
 }
 
-static int rtnl_setlink(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
+static int rtnl_setlink(struct sk_buff *skb, struct nlmsghdr *nlh)
 {
 	struct net *net = sock_net(skb->sk);
 	struct ifinfomsg *ifm;
@@ -1578,7 +1552,7 @@ errout:
 	return err;
 }
 
-static int rtnl_dellink(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
+static int rtnl_dellink(struct sk_buff *skb, struct nlmsghdr *nlh)
 {
 	struct net *net = sock_net(skb->sk);
 	const struct rtnl_link_ops *ops;
@@ -1709,7 +1683,7 @@ static int rtnl_group_changelink(struct net *net, int group,
 	return 0;
 }
 
-static int rtnl_newlink(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
+static int rtnl_newlink(struct sk_buff *skb, struct nlmsghdr *nlh)
 {
 	struct net *net = sock_net(skb->sk);
 	const struct rtnl_link_ops *ops;
@@ -1864,7 +1838,7 @@ out:
 	}
 }
 
-static int rtnl_getlink(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
+static int rtnl_getlink(struct sk_buff *skb, struct nlmsghdr* nlh)
 {
 	struct net *net = sock_net(skb->sk);
 	struct ifinfomsg *ifm;
@@ -2081,7 +2055,7 @@ int ndo_dflt_fdb_add(struct ndmsg *ndm,
 }
 EXPORT_SYMBOL(ndo_dflt_fdb_add);
 
-static int rtnl_fdb_add(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
+static int rtnl_fdb_add(struct sk_buff *skb, struct nlmsghdr *nlh)
 {
 	struct net *net = sock_net(skb->sk);
 	struct ndmsg *ndm;
@@ -2179,7 +2153,7 @@ int ndo_dflt_fdb_del(struct ndmsg *ndm,
 }
 EXPORT_SYMBOL(ndo_dflt_fdb_del);
 
-static int rtnl_fdb_del(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
+static int rtnl_fdb_del(struct sk_buff *skb, struct nlmsghdr *nlh)
 {
 	struct net *net = sock_net(skb->sk);
 	struct ndmsg *ndm;
@@ -2478,8 +2452,7 @@ errout:
 	return err;
 }
 
-static int rtnl_bridge_setlink(struct sk_buff *skb, struct nlmsghdr *nlh,
-			       void *arg)
+static int rtnl_bridge_setlink(struct sk_buff *skb, struct nlmsghdr *nlh)
 {
 	struct net *net = sock_net(skb->sk);
 	struct ifinfomsg *ifm;
@@ -2549,8 +2522,7 @@ out:
 	return err;
 }
 
-static int rtnl_bridge_dellink(struct sk_buff *skb, struct nlmsghdr *nlh,
-			       void *arg)
+static int rtnl_bridge_dellink(struct sk_buff *skb, struct nlmsghdr *nlh)
 {
 	struct net *net = sock_net(skb->sk);
 	struct ifinfomsg *ifm;
@@ -2620,10 +2592,6 @@ out:
 	return err;
 }
 
-/* Protected by RTNL sempahore.  */
-static struct rtattr **rta_buf;
-static int rtattr_max;
-
 /* Process one rtnetlink message. */
 
 static int rtnetlink_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
@@ -2631,7 +2599,6 @@ static int rtnetlink_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
 	struct net *net = sock_net(skb->sk);
 	rtnl_doit_func doit;
 	int sz_idx, kind;
-	int min_len;
 	int family;
 	int type;
 	int err;
@@ -2679,32 +2646,11 @@ static int rtnetlink_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
 		return err;
 	}
 
-	memset(rta_buf, 0, (rtattr_max * sizeof(struct rtattr *)));
-
-	min_len = rtm_min[sz_idx];
-	if (nlh->nlmsg_len < min_len)
-		return -EINVAL;
-
-	if (nlh->nlmsg_len > min_len) {
-		int attrlen = nlh->nlmsg_len - NLMSG_ALIGN(min_len);
-		struct rtattr *attr = (void *)nlh + NLMSG_ALIGN(min_len);
-
-		while (RTA_OK(attr, attrlen)) {
-			unsigned int flavor = attr->rta_type & NLA_TYPE_MASK;
-			if (flavor) {
-				if (flavor > rta_max[sz_idx])
-					return -EINVAL;
-				rta_buf[flavor-1] = attr;
-			}
-			attr = RTA_NEXT(attr, attrlen);
-		}
-	}
-
 	doit = rtnl_get_doit(family, type);
 	if (doit == NULL)
 		return -EOPNOTSUPP;
 
-	return doit(skb, nlh, (void *)&rta_buf[0]);
+	return doit(skb, nlh);
 }
 
 static void rtnetlink_rcv(struct sk_buff *skb)
@@ -2774,16 +2720,6 @@ static struct pernet_operations rtnetlink_net_ops = {
 
 void __init rtnetlink_init(void)
 {
-	int i;
-
-	rtattr_max = 0;
-	for (i = 0; i < ARRAY_SIZE(rta_max); i++)
-		if (rta_max[i] > rtattr_max)
-			rtattr_max = rta_max[i];
-	rta_buf = kmalloc(rtattr_max * sizeof(struct rtattr *), GFP_KERNEL);
-	if (!rta_buf)
-		panic("rtnetlink_init: cannot allocate rta_buf\n");
-
 	if (register_pernet_subsys(&rtnetlink_net_ops))
 		panic("rtnetlink_init: cannot initialize rtnetlink\n");
 
diff --git a/net/dcb/dcbnl.c b/net/dcb/dcbnl.c
index 21291f1..40d5829 100644
--- a/net/dcb/dcbnl.c
+++ b/net/dcb/dcbnl.c
@@ -1658,7 +1658,7 @@ static const struct reply_func reply_funcs[DCB_CMD_MAX+1] = {
 	[DCB_CMD_CEE_GET]	= { RTM_GETDCB, dcbnl_cee_get },
 };
 
-static int dcb_doit(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
+static int dcb_doit(struct sk_buff *skb, struct nlmsghdr *nlh)
 {
 	struct net *net = sock_net(skb->sk);
 	struct net_device *netdev;
diff --git a/net/decnet/dn_dev.c b/net/decnet/dn_dev.c
index c8da116..7d91970 100644
--- a/net/decnet/dn_dev.c
+++ b/net/decnet/dn_dev.c
@@ -563,7 +563,7 @@ static const struct nla_policy dn_ifa_policy[IFA_MAX+1] = {
 				    .len = IFNAMSIZ - 1 },
 };
 
-static int dn_nl_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
+static int dn_nl_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh)
 {
 	struct net *net = sock_net(skb->sk);
 	struct nlattr *tb[IFA_MAX+1];
@@ -607,7 +607,7 @@ errout:
 	return err;
 }
 
-static int dn_nl_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
+static int dn_nl_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh)
 {
 	struct net *net = sock_net(skb->sk);
 	struct nlattr *tb[IFA_MAX+1];
diff --git a/net/decnet/dn_fib.c b/net/decnet/dn_fib.c
index 42a8048..f093059 100644
--- a/net/decnet/dn_fib.c
+++ b/net/decnet/dn_fib.c
@@ -511,7 +511,7 @@ static inline u32 rtm_get_table(struct nlattr *attrs[], u8 table)
 	return table;
 }
 
-static int dn_fib_rtm_delroute(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
+static int dn_fib_rtm_delroute(struct sk_buff *skb, struct nlmsghdr *nlh)
 {
 	struct net *net = sock_net(skb->sk);
 	struct dn_fib_table *tb;
@@ -536,7 +536,7 @@ static int dn_fib_rtm_delroute(struct sk_buff *skb, struct nlmsghdr *nlh, void *
 	return tb->delete(tb, r, attrs, nlh, &NETLINK_CB(skb));
 }
 
-static int dn_fib_rtm_newroute(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
+static int dn_fib_rtm_newroute(struct sk_buff *skb, struct nlmsghdr *nlh)
 {
 	struct net *net = sock_net(skb->sk);
 	struct dn_fib_table *tb;
diff --git a/net/decnet/dn_route.c b/net/decnet/dn_route.c
index b4b3508..5904429 100644
--- a/net/decnet/dn_route.c
+++ b/net/decnet/dn_route.c
@@ -1616,7 +1616,7 @@ errout:
 /*
  * This is called by both endnodes and routers now.
  */
-static int dn_cache_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh, void *arg)
+static int dn_cache_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh)
 {
 	struct net *net = sock_net(in_skb->sk);
 	struct rtmsg *rtm = nlmsg_data(nlh);
diff --git a/net/ipv4/devinet.c b/net/ipv4/devinet.c
index af57bba..20a9f92 100644
--- a/net/ipv4/devinet.c
+++ b/net/ipv4/devinet.c
@@ -536,7 +536,7 @@ struct in_ifaddr *inet_ifa_byprefix(struct in_device *in_dev, __be32 prefix,
 	return NULL;
 }
 
-static int inet_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
+static int inet_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh)
 {
 	struct net *net = sock_net(skb->sk);
 	struct nlattr *tb[IFA_MAX+1];
@@ -775,7 +775,7 @@ static struct in_ifaddr *find_matching_ifa(struct in_ifaddr *ifa)
 	return NULL;
 }
 
-static int inet_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
+static int inet_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh)
 {
 	struct net *net = sock_net(skb->sk);
 	struct in_ifaddr *ifa;
@@ -1730,8 +1730,7 @@ static const struct nla_policy devconf_ipv4_policy[NETCONFA_MAX+1] = {
 };
 
 static int inet_netconf_get_devconf(struct sk_buff *in_skb,
-				    struct nlmsghdr *nlh,
-				    void *arg)
+				    struct nlmsghdr *nlh)
 {
 	struct net *net = sock_net(in_skb->sk);
 	struct nlattr *tb[NETCONFA_MAX+1];
diff --git a/net/ipv4/fib_frontend.c b/net/ipv4/fib_frontend.c
index eb4bb12..0e74398 100644
--- a/net/ipv4/fib_frontend.c
+++ b/net/ipv4/fib_frontend.c
@@ -604,7 +604,7 @@ errout:
 	return err;
 }
 
-static int inet_rtm_delroute(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
+static int inet_rtm_delroute(struct sk_buff *skb, struct nlmsghdr *nlh)
 {
 	struct net *net = sock_net(skb->sk);
 	struct fib_config cfg;
@@ -626,7 +626,7 @@ errout:
 	return err;
 }
 
-static int inet_rtm_newroute(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
+static int inet_rtm_newroute(struct sk_buff *skb, struct nlmsghdr *nlh)
 {
 	struct net *net = sock_net(skb->sk);
 	struct fib_config cfg;
diff --git a/net/ipv4/route.c b/net/ipv4/route.c
index 6e28514..550781a 100644
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c
@@ -2311,7 +2311,7 @@ nla_put_failure:
 	return -EMSGSIZE;
 }
 
-static int inet_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh, void *arg)
+static int inet_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh)
 {
 	struct net *net = sock_net(in_skb->sk);
 	struct rtmsg *rtm;
diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index fa36a67..15794fd 100644
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -544,8 +544,7 @@ static const struct nla_policy devconf_ipv6_policy[NETCONFA_MAX+1] = {
 };
 
 static int inet6_netconf_get_devconf(struct sk_buff *in_skb,
-				     struct nlmsghdr *nlh,
-				     void *arg)
+				     struct nlmsghdr *nlh)
 {
 	struct net *net = sock_net(in_skb->sk);
 	struct nlattr *tb[NETCONFA_MAX+1];
@@ -3578,7 +3577,7 @@ static const struct nla_policy ifa_ipv6_policy[IFA_MAX+1] = {
 };
 
 static int
-inet6_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
+inet6_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh)
 {
 	struct net *net = sock_net(skb->sk);
 	struct ifaddrmsg *ifm;
@@ -3644,7 +3643,7 @@ static int inet6_addr_modify(struct inet6_ifaddr *ifp, u8 ifa_flags,
 }
 
 static int
-inet6_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
+inet6_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh)
 {
 	struct net *net = sock_net(skb->sk);
 	struct ifaddrmsg *ifm;
@@ -3983,8 +3982,7 @@ static int inet6_dump_ifacaddr(struct sk_buff *skb, struct netlink_callback *cb)
 	return inet6_dump_addr(skb, cb, type);
 }
 
-static int inet6_rtm_getaddr(struct sk_buff *in_skb, struct nlmsghdr *nlh,
-			     void *arg)
+static int inet6_rtm_getaddr(struct sk_buff *in_skb, struct nlmsghdr *nlh)
 {
 	struct net *net = sock_net(in_skb->sk);
 	struct ifaddrmsg *ifm;
diff --git a/net/ipv6/addrlabel.c b/net/ipv6/addrlabel.c
index 6f226c8..f083a58 100644
--- a/net/ipv6/addrlabel.c
+++ b/net/ipv6/addrlabel.c
@@ -414,8 +414,7 @@ static const struct nla_policy ifal_policy[IFAL_MAX+1] = {
 	[IFAL_LABEL]		= { .len = sizeof(u32), },
 };
 
-static int ip6addrlbl_newdel(struct sk_buff *skb, struct nlmsghdr *nlh,
-			     void *arg)
+static int ip6addrlbl_newdel(struct sk_buff *skb, struct nlmsghdr *nlh)
 {
 	struct net *net = sock_net(skb->sk);
 	struct ifaddrlblmsg *ifal;
@@ -530,8 +529,7 @@ static inline int ip6addrlbl_msgsize(void)
 		+ nla_total_size(4);	/* IFAL_LABEL */
 }
 
-static int ip6addrlbl_get(struct sk_buff *in_skb, struct nlmsghdr* nlh,
-			  void *arg)
+static int ip6addrlbl_get(struct sk_buff *in_skb, struct nlmsghdr* nlh)
 {
 	struct net *net = sock_net(in_skb->sk);
 	struct ifaddrlblmsg *ifal;
diff --git a/net/ipv6/route.c b/net/ipv6/route.c
index e5fe004..ad0aa6b 100644
--- a/net/ipv6/route.c
+++ b/net/ipv6/route.c
@@ -2355,7 +2355,7 @@ beginning:
 	return last_err;
 }
 
-static int inet6_rtm_delroute(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
+static int inet6_rtm_delroute(struct sk_buff *skb, struct nlmsghdr* nlh)
 {
 	struct fib6_config cfg;
 	int err;
@@ -2370,7 +2370,7 @@ static int inet6_rtm_delroute(struct sk_buff *skb, struct nlmsghdr* nlh, void *a
 		return ip6_route_del(&cfg);
 }
 
-static int inet6_rtm_newroute(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
+static int inet6_rtm_newroute(struct sk_buff *skb, struct nlmsghdr* nlh)
 {
 	struct fib6_config cfg;
 	int err;
@@ -2562,7 +2562,7 @@ int rt6_dump_route(struct rt6_info *rt, void *p_arg)
 		     prefix, 0, NLM_F_MULTI);
 }
 
-static int inet6_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr* nlh, void *arg)
+static int inet6_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr* nlh)
 {
 	struct net *net = sock_net(in_skb->sk);
 	struct nlattr *tb[RTA_MAX+1];
diff --git a/net/phonet/pn_netlink.c b/net/phonet/pn_netlink.c
index 0193630..dc15f43 100644
--- a/net/phonet/pn_netlink.c
+++ b/net/phonet/pn_netlink.c
@@ -61,7 +61,7 @@ static const struct nla_policy ifa_phonet_policy[IFA_MAX+1] = {
 	[IFA_LOCAL] = { .type = NLA_U8 },
 };
 
-static int addr_doit(struct sk_buff *skb, struct nlmsghdr *nlh, void *attr)
+static int addr_doit(struct sk_buff *skb, struct nlmsghdr *nlh)
 {
 	struct net *net = sock_net(skb->sk);
 	struct nlattr *tb[IFA_MAX+1];
@@ -224,7 +224,7 @@ static const struct nla_policy rtm_phonet_policy[RTA_MAX+1] = {
 	[RTA_OIF] = { .type = NLA_U32 },
 };
 
-static int route_doit(struct sk_buff *skb, struct nlmsghdr *nlh, void *attr)
+static int route_doit(struct sk_buff *skb, struct nlmsghdr *nlh)
 {
 	struct net *net = sock_net(skb->sk);
 	struct nlattr *tb[RTA_MAX+1];
diff --git a/net/sched/act_api.c b/net/sched/act_api.c
index 8579c4b..fd70728 100644
--- a/net/sched/act_api.c
+++ b/net/sched/act_api.c
@@ -982,7 +982,7 @@ done:
 	return ret;
 }
 
-static int tc_ctl_action(struct sk_buff *skb, struct nlmsghdr *n, void *arg)
+static int tc_ctl_action(struct sk_buff *skb, struct nlmsghdr *n)
 {
 	struct net *net = sock_net(skb->sk);
 	struct nlattr *tca[TCA_ACT_MAX + 1];
diff --git a/net/sched/cls_api.c b/net/sched/cls_api.c
index 964f5e4..9a04b98 100644
--- a/net/sched/cls_api.c
+++ b/net/sched/cls_api.c
@@ -118,7 +118,7 @@ static inline u32 tcf_auto_prio(struct tcf_proto *tp)
 
 /* Add/change/delete/get a filter node */
 
-static int tc_ctl_tfilter(struct sk_buff *skb, struct nlmsghdr *n, void *arg)
+static int tc_ctl_tfilter(struct sk_buff *skb, struct nlmsghdr *n)
 {
 	struct net *net = sock_net(skb->sk);
 	struct nlattr *tca[TCA_MAX + 1];
diff --git a/net/sched/sch_api.c b/net/sched/sch_api.c
index c297e2a..0bbce22 100644
--- a/net/sched/sch_api.c
+++ b/net/sched/sch_api.c
@@ -971,7 +971,7 @@ check_loop_fn(struct Qdisc *q, unsigned long cl, struct qdisc_walker *w)
  * Delete/get qdisc.
  */
 
-static int tc_get_qdisc(struct sk_buff *skb, struct nlmsghdr *n, void *arg)
+static int tc_get_qdisc(struct sk_buff *skb, struct nlmsghdr *n)
 {
 	struct net *net = sock_net(skb->sk);
 	struct tcmsg *tcm = nlmsg_data(n);
@@ -1038,7 +1038,7 @@ static int tc_get_qdisc(struct sk_buff *skb, struct nlmsghdr *n, void *arg)
  * Create/change qdisc.
  */
 
-static int tc_modify_qdisc(struct sk_buff *skb, struct nlmsghdr *n, void *arg)
+static int tc_modify_qdisc(struct sk_buff *skb, struct nlmsghdr *n)
 {
 	struct net *net = sock_net(skb->sk);
 	struct tcmsg *tcm;
@@ -1372,7 +1372,7 @@ done:
 
 
 
-static int tc_ctl_tclass(struct sk_buff *skb, struct nlmsghdr *n, void *arg)
+static int tc_ctl_tclass(struct sk_buff *skb, struct nlmsghdr *n)
 {
 	struct net *net = sock_net(skb->sk);
 	struct tcmsg *tcm = nlmsg_data(n);
-- 
1.7.11.7

Re: [PATCH net-next 0/2] Get rid of attribute parsing in rtnetlink_rcv_msg()

[David Miller]

From: Thomas Graf <tgraf@suug.ch>
Date: Thu, 21 Mar 2013 18:45:27 +0100

> We have been wanting to get rid of rta_buf for a while. It is error
> prone as it requires subsystems, especially modules, that register a
> rtnetlink mesage type to also modify rtnetlink.c and thus require
> the recompilation of the kernel. DECnet is the only user left so after
> converting it we can safely remove it
> 
> Thomas Graf (2):
>   decnet: Parse netlink attributes on our own
>   rtnetlink: Remove passing of attributes into rtnl_doit functions

Looks great.

I'll apply this once at least some basic sanity test has been done
on the decnet bits.

Thanks.