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net: Add extack for route add/delete failures

PATCH In review David Ahern 2 participants 6 messages May 21, 2017 – May 22, 2017

Subsystems (3)
Networking Network drivers IPv4/IPv6
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David Ahern

author
#0 lore raw

cover net: Add extack for route add/delete failures

Use the extack feature to improve error messages to user on route add and delete failures.

David Ahern (4):
net: ipv4: Plumb extack through route add functions
net: ipv4: Add extack messages for route add failures
net: ipv6: Plumb extack through route add functions
net: ipv6: Add extack messages for route add failures

 include/linux/netlink.h  |   5 ++
 include/net/ip6_fib.h    |   3 +-
 include/net/ip6_route.h  |   2 +-
 include/net/ip_fib.h     |   3 +-
 net/ipv4/fib_frontend.c  |  18 ++++---
 net/ipv4/fib_lookup.h    |   3 +-
 net/ipv4/fib_semantics.c | 133 ++++++++++++++++++++++++++++++++++++-----------
 net/ipv4/fib_trie.c      |   4 +-
 net/ipv6/addrconf.c      |   4 +-
 net/ipv6/ip6_fib.c       |  18 +++++--
 net/ipv6/route.c         |  97 ++++++++++++++++++++++------------
 11 files changed, 208 insertions(+), 82 deletions(-)
Signature · 1 line
2.11.0 (Apple Git-81)
author
#1 lore raw

PATCH 1/4 net: ipv4: Plumb extack through route add functions

Plumb extack argument down to route add functions.

Signed-off-by David Ahern <[email protected]>
---
 include/net/ip_fib.h     |  3 ++-
 net/ipv4/fib_frontend.c  | 16 +++++++++-------
 net/ipv4/fib_lookup.h    |  3 ++-
 net/ipv4/fib_semantics.c | 22 +++++++++++++---------
 net/ipv4/fib_trie.c      |  4 ++--
 5 files changed, 28 insertions(+), 20 deletions(-)
include/net/ip_fib.h +2 -1
index 6692c5758b33..42e8b8f55f7c 100644
@@ -263,7 +263,8 @@ struct fib_table {
 
 int fib_table_lookup(struct fib_table *tb, const struct flowi4 *flp,
 		     struct fib_result *res, int fib_flags);
-int fib_table_insert(struct net *, struct fib_table *, struct fib_config *);
+int fib_table_insert(struct net *, struct fib_table *, struct fib_config *,
+		     struct netlink_ext_ack *extack);
 int fib_table_delete(struct net *, struct fib_table *, struct fib_config *);
 int fib_table_dump(struct fib_table *table, struct sk_buff *skb,
 		   struct netlink_callback *cb);
net/ipv4/fib_frontend.c +9 -7
index 83e3ed258467..511edff76c01 100644
@@ -594,7 +594,8 @@ int ip_rt_ioctl(struct net *net, unsigned int cmd, void __user *arg)
 			} else {
 				tb = fib_new_table(net, cfg.fc_table);
 				if (tb)
-					err = fib_table_insert(net, tb, &cfg);
+					err = fib_table_insert(net, tb,
+							       &cfg, NULL);
 				else
 					err = -ENOBUFS;
 			}

@@ -626,14 +627,15 @@ const struct nla_policy rtm_ipv4_policy[RTA_MAX + 1] = {
 };
 
 static int rtm_to_fib_config(struct net *net, struct sk_buff *skb,
-			     struct nlmsghdr *nlh, struct fib_config *cfg)
+			     struct nlmsghdr *nlh, struct fib_config *cfg,
+			     struct netlink_ext_ack *extack)
 {
 	struct nlattr *attr;
 	int err, remaining;
 	struct rtmsg *rtm;
 
 	err = nlmsg_validate(nlh, sizeof(*rtm), RTA_MAX, rtm_ipv4_policy,
-			     NULL);
+			     extack);
 	if (err < 0)
 		goto errout;
 

@@ -718,7 +720,7 @@ static int inet_rtm_delroute(struct sk_buff *skb, struct nlmsghdr *nlh,
 	struct fib_table *tb;
 	int err;
 
-	err = rtm_to_fib_config(net, skb, nlh, &cfg);
+	err = rtm_to_fib_config(net, skb, nlh, &cfg, extack);
 	if (err < 0)
 		goto errout;
 

@@ -741,7 +743,7 @@ static int inet_rtm_newroute(struct sk_buff *skb, struct nlmsghdr *nlh,
 	struct fib_table *tb;
 	int err;
 
-	err = rtm_to_fib_config(net, skb, nlh, &cfg);
+	err = rtm_to_fib_config(net, skb, nlh, &cfg, extack);
 	if (err < 0)
 		goto errout;
 

@@ -751,7 +753,7 @@ static int inet_rtm_newroute(struct sk_buff *skb, struct nlmsghdr *nlh,
 		goto errout;
 	}
 
-	err = fib_table_insert(net, tb, &cfg);
+	err = fib_table_insert(net, tb, &cfg, extack);
 errout:
 	return err;
 }

@@ -845,7 +847,7 @@ static void fib_magic(int cmd, int type, __be32 dst, int dst_len, struct in_ifad
 		cfg.fc_scope = RT_SCOPE_HOST;
 
 	if (cmd == RTM_NEWROUTE)
-		fib_table_insert(net, tb, &cfg);
+		fib_table_insert(net, tb, &cfg, NULL);
 	else
 		fib_table_delete(net, tb, &cfg);
 }
net/ipv4/fib_lookup.h +2 -1
index 9c02920725db..2704e08545da 100644
@@ -28,7 +28,8 @@ static inline void fib_alias_accessed(struct fib_alias *fa)
 
 /* Exported by fib_semantics.c */
 void fib_release_info(struct fib_info *);
-struct fib_info *fib_create_info(struct fib_config *cfg);
+struct fib_info *fib_create_info(struct fib_config *cfg,
+				 struct netlink_ext_ack *extack);
 int fib_nh_match(struct fib_config *cfg, struct fib_info *fi);
 int fib_dump_info(struct sk_buff *skb, u32 pid, u32 seq, int event, u32 tb_id,
 		  u8 type, __be32 dst, int dst_len, u8 tos, struct fib_info *fi,
net/ipv4/fib_semantics.c +13 -9
index da449ddb8cc1..8587d1b55b53 100644
@@ -454,7 +454,8 @@ static int fib_detect_death(struct fib_info *fi, int order,
 
 #ifdef CONFIG_IP_ROUTE_MULTIPATH
 
-static int fib_count_nexthops(struct rtnexthop *rtnh, int remaining)
+static int fib_count_nexthops(struct rtnexthop *rtnh, int remaining,
+			      struct netlink_ext_ack *extack)
 {
 	int nhs = 0;
 

@@ -468,7 +469,8 @@ static int fib_count_nexthops(struct rtnexthop *rtnh, int remaining)
 }
 
 static int fib_get_nhs(struct fib_info *fi, struct rtnexthop *rtnh,
-		       int remaining, struct fib_config *cfg)
+		       int remaining, struct fib_config *cfg,
+		       struct netlink_ext_ack *extack)
 {
 	int ret;
 

@@ -714,7 +716,7 @@ int fib_nh_match(struct fib_config *cfg, struct fib_info *fi)
  *					|-> {local prefix} (terminal node)
  */
 static int fib_check_nh(struct fib_config *cfg, struct fib_info *fi,
-			struct fib_nh *nh)
+			struct fib_nh *nh, struct netlink_ext_ack *extack)
 {
 	int err = 0;
 	struct net *net;

@@ -797,7 +799,6 @@ static int fib_check_nh(struct fib_config *cfg, struct fib_info *fi,
 
 		if (nh->nh_flags & (RTNH_F_PERVASIVE | RTNH_F_ONLINK))
 			return -EINVAL;
-
 		rcu_read_lock();
 		err = -ENODEV;
 		in_dev = inetdev_by_index(net, nh->nh_oif);

@@ -980,7 +981,8 @@ fib_convert_metrics(struct fib_info *fi, const struct fib_config *cfg)
 	return 0;
 }
 
-struct fib_info *fib_create_info(struct fib_config *cfg)
+struct fib_info *fib_create_info(struct fib_config *cfg,
+				 struct netlink_ext_ack *extack)
 {
 	int err;
 	struct fib_info *fi = NULL;

@@ -1000,7 +1002,7 @@ struct fib_info *fib_create_info(struct fib_config *cfg)
 
 #ifdef CONFIG_IP_ROUTE_MULTIPATH
 	if (cfg->fc_mp) {
-		nhs = fib_count_nexthops(cfg->fc_mp, cfg->fc_mp_len);
+		nhs = fib_count_nexthops(cfg->fc_mp, cfg->fc_mp_len, extack);
 		if (nhs == 0)
 			goto err_inval;
 	}

@@ -1062,7 +1064,7 @@ struct fib_info *fib_create_info(struct fib_config *cfg)
 
 	if (cfg->fc_mp) {
 #ifdef CONFIG_IP_ROUTE_MULTIPATH
-		err = fib_get_nhs(fi, cfg->fc_mp, cfg->fc_mp_len, cfg);
+		err = fib_get_nhs(fi, cfg->fc_mp, cfg->fc_mp_len, cfg, extack);
 		if (err != 0)
 			goto failure;
 		if (cfg->fc_oif && fi->fib_nh->nh_oif != cfg->fc_oif)

@@ -1129,7 +1131,9 @@ struct fib_info *fib_create_info(struct fib_config *cfg)
 		struct fib_nh *nh = fi->fib_nh;
 
 		/* Local address is added. */
-		if (nhs != 1 || nh->nh_gw)
+		if (nhs != 1)
+			goto err_inval;
+		if (nh->nh_gw)
 			goto err_inval;
 		nh->nh_scope = RT_SCOPE_NOWHERE;
 		nh->nh_dev = dev_get_by_index(net, fi->fib_nh->nh_oif);

@@ -1140,7 +1144,7 @@ struct fib_info *fib_create_info(struct fib_config *cfg)
 		int linkdown = 0;
 
 		change_nexthops(fi) {
-			err = fib_check_nh(cfg, fi, nexthop_nh);
+			err = fib_check_nh(cfg, fi, nexthop_nh, extack);
 			if (err != 0)
 				goto failure;
 			if (nexthop_nh->nh_flags & RTNH_F_LINKDOWN)
net/ipv4/fib_trie.c +2 -2
index 51182ff2b441..6d0f6c79d9aa 100644
@@ -1101,7 +1101,7 @@ static int fib_insert_alias(struct trie *t, struct key_vector *tp,
 
 /* Caller must hold RTNL. */
 int fib_table_insert(struct net *net, struct fib_table *tb,
-		     struct fib_config *cfg)
+		     struct fib_config *cfg, struct netlink_ext_ack *extack)
 {
 	enum fib_event_type event = FIB_EVENT_ENTRY_ADD;
 	struct trie *t = (struct trie *)tb->tb_data;

@@ -1125,7 +1125,7 @@ int fib_table_insert(struct net *net, struct fib_table *tb,
 	if ((plen < KEYLENGTH) && (key << plen))
 		return -EINVAL;
 
-	fi = fib_create_info(cfg);
+	fi = fib_create_info(cfg, extack);
 	if (IS_ERR(fi)) {
 		err = PTR_ERR(fi);
 		goto err;
Signature · 1 line
2.11.0 (Apple Git-81)
author
#2 lore raw

PATCH 2/4 net: ipv4: Add extack messages for route add failures

In reply to David Ahern

Add messages for non-obvious errors (e.g, no need to add text for malloc failures or ENODEV failures). This mostly covers the annoying EINVAL errors Some message strings violate the 80-columns but searchable strings need to trump that rule.

Signed-off-by David Ahern <[email protected]>
---
 include/linux/netlink.h  |   5 +++
 net/ipv4/fib_frontend.c  |   2 +
 net/ipv4/fib_semantics.c | 115 ++++++++++++++++++++++++++++++++++++++---------
 3 files changed, 100 insertions(+), 22 deletions(-)
include/linux/netlink.h +5 -0
index 5fff5ba5964e..a68aad484c69 100644
@@ -97,6 +97,11 @@ struct netlink_ext_ack {
 #define NL_SET_ERR_MSG_MOD(extack, msg)			\
 	NL_SET_ERR_MSG((extack), KBUILD_MODNAME ": " msg)
 
+#define NL_SET_BAD_ATTR(extack, attr) do {		\
+	if ((extack))					\
+		(extack)->bad_attr = (attr);		\
+} while (0)
+
 extern void netlink_kernel_release(struct sock *sk);
 extern int __netlink_change_ngroups(struct sock *sk, unsigned int groups);
 extern int netlink_change_ngroups(struct sock *sk, unsigned int groups);
net/ipv4/fib_frontend.c +2 -0
index 511edff76c01..14d2f7bd7c76 100644
@@ -656,6 +656,7 @@ static int rtm_to_fib_config(struct net *net, struct sk_buff *skb,
 	cfg->fc_nlinfo.nl_net = net;
 
 	if (cfg->fc_type > RTN_MAX) {
+		NL_SET_ERR_MSG(extack, "Invalid route type");
 		err = -EINVAL;
 		goto errout;
 	}

@@ -726,6 +727,7 @@ static int inet_rtm_delroute(struct sk_buff *skb, struct nlmsghdr *nlh,
 
 	tb = fib_get_table(net, cfg.fc_table);
 	if (!tb) {
+		NL_SET_ERR_MSG(extack, "FIB table does not exist");
 		err = -ESRCH;
 		goto errout;
 	}
net/ipv4/fib_semantics.c +93 -22

246 lines not on this page · raw message

Signature · 1 line
2.11.0 (Apple Git-81)
author
#3 lore raw

PATCH 3/4 net: ipv6: Plumb extack through route add functions

In reply to David Ahern

Plumb extack argument down to route add functions.

Signed-off-by David Ahern <[email protected]>
---
 include/net/ip6_fib.h   |  3 ++-
 include/net/ip6_route.h |  2 +-
 net/ipv6/addrconf.c     |  4 ++--
 net/ipv6/ip6_fib.c      | 14 +++++++-----
 net/ipv6/route.c        | 57 +++++++++++++++++++++++++++----------------------
 5 files changed, 46 insertions(+), 34 deletions(-)
include/net/ip6_fib.h +2 -1
index c979c878df1c..aa50e2e6fa2a 100644
@@ -277,7 +277,8 @@ void fib6_clean_all(struct net *net, int (*func)(struct rt6_info *, void *arg),
 		    void *arg);
 
 int fib6_add(struct fib6_node *root, struct rt6_info *rt,
-	     struct nl_info *info, struct mx6_config *mxc);
+	     struct nl_info *info, struct mx6_config *mxc,
+	     struct netlink_ext_ack *extack);
 int fib6_del(struct rt6_info *rt, struct nl_info *info);
 
 void inet6_rt_notify(int event, struct rt6_info *rt, struct nl_info *info,
include/net/ip6_route.h +1 -1
index f5e625f53367..f3da9dd2a8db 100644
@@ -90,7 +90,7 @@ void ip6_route_cleanup(void);
 
 int ipv6_route_ioctl(struct net *net, unsigned int cmd, void __user *arg);
 
-int ip6_route_add(struct fib6_config *cfg);
+int ip6_route_add(struct fib6_config *cfg, struct netlink_ext_ack *extack);
 int ip6_ins_rt(struct rt6_info *);
 int ip6_del_rt(struct rt6_info *);
net/ipv6/addrconf.c +2 -2
index 6a4fb1e629fb..25443fd946a8 100644
@@ -2280,7 +2280,7 @@ addrconf_prefix_route(struct in6_addr *pfx, int plen, struct net_device *dev,
 		cfg.fc_flags |= RTF_NONEXTHOP;
 #endif
 
-	ip6_route_add(&cfg);
+	ip6_route_add(&cfg, NULL);
 }
 
 

@@ -2335,7 +2335,7 @@ static void addrconf_add_mroute(struct net_device *dev)
 
 	ipv6_addr_set(&cfg.fc_dst, htonl(0xFF000000), 0, 0, 0);
 
-	ip6_route_add(&cfg);
+	ip6_route_add(&cfg, NULL);
 }
 
 static struct inet6_dev *addrconf_add_dev(struct net_device *dev)
net/ipv6/ip6_fib.c +9 -5
index d4bf2c68a545..c1197e167d3e 100644
@@ -473,7 +473,8 @@ static int inet6_dump_fib(struct sk_buff *skb, struct netlink_callback *cb)
 static struct fib6_node *fib6_add_1(struct fib6_node *root,
 				     struct in6_addr *addr, int plen,
 				     int offset, int allow_create,
-				     int replace_required, int sernum)
+				     int replace_required, int sernum,
+				     struct netlink_ext_ack *extack)
 {
 	struct fib6_node *fn, *in, *ln;
 	struct fib6_node *pn = NULL;

@@ -964,7 +965,8 @@ void fib6_force_start_gc(struct net *net)
  */
 
 int fib6_add(struct fib6_node *root, struct rt6_info *rt,
-	     struct nl_info *info, struct mx6_config *mxc)
+	     struct nl_info *info, struct mx6_config *mxc,
+	     struct netlink_ext_ack *extack)
 {
 	struct fib6_node *fn, *pn = NULL;
 	int err = -ENOMEM;

@@ -987,7 +989,7 @@ int fib6_add(struct fib6_node *root, struct rt6_info *rt,
 
 	fn = fib6_add_1(root, &rt->rt6i_dst.addr, rt->rt6i_dst.plen,
 			offsetof(struct rt6_info, rt6i_dst), allow_create,
-			replace_required, sernum);
+			replace_required, sernum, extack);
 	if (IS_ERR(fn)) {
 		err = PTR_ERR(fn);
 		fn = NULL;

@@ -1028,7 +1030,8 @@ int fib6_add(struct fib6_node *root, struct rt6_info *rt,
 			sn = fib6_add_1(sfn, &rt->rt6i_src.addr,
 					rt->rt6i_src.plen,
 					offsetof(struct rt6_info, rt6i_src),
-					allow_create, replace_required, sernum);
+					allow_create, replace_required, sernum,
+					extack);
 
 			if (IS_ERR(sn)) {
 				/* If it is failed, discard just allocated

@@ -1047,7 +1050,8 @@ int fib6_add(struct fib6_node *root, struct rt6_info *rt,
 			sn = fib6_add_1(fn->subtree, &rt->rt6i_src.addr,
 					rt->rt6i_src.plen,
 					offsetof(struct rt6_info, rt6i_src),
-					allow_create, replace_required, sernum);
+					allow_create, replace_required, sernum,
+					extack);
 
 			if (IS_ERR(sn)) {
 				err = PTR_ERR(sn);
net/ipv6/route.c +32 -25

189 lines not on this page · raw message

Signature · 1 line
2.11.0 (Apple Git-81)
author
#4 lore raw

PATCH 4/4 net: ipv6: Add extack messages for route add failures

In reply to David Ahern

Add messages for non-obvious errors (e.g, no need to add text for malloc failures or ENODEV failures). This mostly covers the annoying EINVAL errors Some message strings violate the 80-columns but searchable strings need to trump that rule.

Signed-off-by David Ahern <[email protected]>
---
 net/ipv6/ip6_fib.c |  4 ++++
 net/ipv6/route.c   | 40 ++++++++++++++++++++++++++++++++--------
 2 files changed, 36 insertions(+), 8 deletions(-)
net/ipv6/ip6_fib.c +4 -0
index c1197e167d3e..deea901746c8 100644
@@ -498,6 +498,8 @@ static struct fib6_node *fib6_add_1(struct fib6_node *root,
 		    !ipv6_prefix_equal(&key->addr, addr, fn->fn_bit)) {
 			if (!allow_create) {
 				if (replace_required) {
+					NL_SET_ERR_MSG(extack,
+						       "Can not replace route - no match found");
 					pr_warn("Can't replace route, no match found\n");
 					return ERR_PTR(-ENOENT);
 				}

@@ -544,6 +546,8 @@ static struct fib6_node *fib6_add_1(struct fib6_node *root,
 		 * That would keep IPv6 consistent with IPv4
 		 */
 		if (replace_required) {
+			NL_SET_ERR_MSG(extack,
+				       "Can not replace route - no match found");
 			pr_warn("Can't replace route, no match found\n");
 			return ERR_PTR(-ENOENT);
 		}
net/ipv6/route.c +32 -8
index ca754ec4054a..80bda31ffbbe 100644
@@ -1857,14 +1857,25 @@ static struct rt6_info *ip6_route_info_create(struct fib6_config *cfg,
 	int err = -EINVAL;
 
 	/* RTF_PCPU is an internal flag; can not be set by userspace */
-	if (cfg->fc_flags & RTF_PCPU)
+	if (cfg->fc_flags & RTF_PCPU) {
+		NL_SET_ERR_MSG(extack, "Userspace can not set RTF_PCPU");
 		goto out;
+	}
 
-	if (cfg->fc_dst_len > 128 || cfg->fc_src_len > 128)
+	if (cfg->fc_dst_len > 128) {
+		NL_SET_ERR_MSG(extack, "Invalid prefix length");
+		goto out;
+	}
+	if (cfg->fc_src_len > 128) {
+		NL_SET_ERR_MSG(extack, "Invalid source address length");
 		goto out;
+	}
 #ifndef CONFIG_IPV6_SUBTREES
-	if (cfg->fc_src_len)
+	if (cfg->fc_src_len) {
+		NL_SET_ERR_MSG(extack,
+			       "Specifying source address requires IPV6_SUBTREES to be enabled");
 		goto out;
+	}
 #endif
 	if (cfg->fc_ifindex) {
 		err = -ENODEV;

@@ -2015,9 +2026,10 @@ static struct rt6_info *ip6_route_info_create(struct fib6_config *cfg,
 		err = -EINVAL;
 		if (ipv6_chk_addr_and_flags(net, gw_addr,
 					    gwa_type & IPV6_ADDR_LINKLOCAL ?
-					    dev : NULL, 0, 0))
+					    dev : NULL, 0, 0)) {
+			NL_SET_ERR_MSG(extack, "Invalid gateway address");
 			goto out;
-
+		}
 		rt->rt6i_gateway = *gw_addr;
 
 		if (gwa_type != (IPV6_ADDR_LINKLOCAL|IPV6_ADDR_UNICAST)) {

@@ -2033,8 +2045,11 @@ static struct rt6_info *ip6_route_info_create(struct fib6_config *cfg,
 			   addressing
 			 */
 			if (!(gwa_type & (IPV6_ADDR_UNICAST |
-					  IPV6_ADDR_MAPPED)))
+					  IPV6_ADDR_MAPPED))) {
+				NL_SET_ERR_MSG(extack,
+					       "Invalid gateway address");
 				goto out;
+			}
 
 			if (cfg->fc_table) {
 				grt = ip6_nh_lookup_table(net, cfg, gw_addr);

@@ -2074,8 +2089,14 @@ static struct rt6_info *ip6_route_info_create(struct fib6_config *cfg,
 				goto out;
 		}
 		err = -EINVAL;
-		if (!dev || (dev->flags & IFF_LOOPBACK))
+		if (!dev) {
+			NL_SET_ERR_MSG(extack, "Egress device not specified");
+			goto out;
+		} else if (dev->flags & IFF_LOOPBACK) {
+			NL_SET_ERR_MSG(extack,
+				       "Egress device can not be loopback device for this route");
 			goto out;
+		}
 	}
 
 	err = -ENODEV;

@@ -2084,6 +2105,7 @@ static struct rt6_info *ip6_route_info_create(struct fib6_config *cfg,
 
 	if (!ipv6_addr_any(&cfg->fc_prefsrc)) {
 		if (!ipv6_chk_addr(net, &cfg->fc_prefsrc, dev, 0)) {
+			NL_SET_ERR_MSG(extack, "Invalid source address");
 			err = -EINVAL;
 			goto out;
 		}

@@ -2234,8 +2256,10 @@ static int ip6_route_del(struct fib6_config *cfg,
 	int err = -ESRCH;
 
 	table = fib6_get_table(cfg->fc_nlinfo.nl_net, cfg->fc_table);
-	if (!table)
+	if (!table) {
+		NL_SET_ERR_MSG(extack, "FIB table does not exist");
 		return err;
+	}
 
 	read_lock_bh(&table->tb6_lock);
Signature · 1 line
2.11.0 (Apple Git-81)