1 files changed, 101 insertions, 59 deletions

diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index e84d108cfee4..20b550d07fe3 100644
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -453,7 +453,7 @@ static const struct rtnl_af_ops *rtnl_af_lookup(const int family)
 {
 	const struct rtnl_af_ops *ops;
 
-	list_for_each_entry(ops, &rtnl_af_ops, list) {
+	list_for_each_entry_rcu(ops, &rtnl_af_ops, list) {
 		if (ops->family == family)
 			return ops;
 	}
@@ -470,7 +470,7 @@ static const struct rtnl_af_ops *rtnl_af_lookup(const int family)
 void rtnl_af_register(struct rtnl_af_ops *ops)
 {
 	rtnl_lock();
-	list_add_tail(&ops->list, &rtnl_af_ops);
+	list_add_tail_rcu(&ops->list, &rtnl_af_ops);
 	rtnl_unlock();
 }
 EXPORT_SYMBOL_GPL(rtnl_af_register);
@@ -482,8 +482,10 @@ EXPORT_SYMBOL_GPL(rtnl_af_register);
 void rtnl_af_unregister(struct rtnl_af_ops *ops)
 {
 	rtnl_lock();
-	list_del(&ops->list);
+	list_del_rcu(&ops->list);
 	rtnl_unlock();
+
+	synchronize_rcu();
 }
 EXPORT_SYMBOL_GPL(rtnl_af_unregister);
 
@@ -496,13 +498,15 @@ static size_t rtnl_link_get_af_size(const struct net_device *dev,
 	/* IFLA_AF_SPEC */
 	size = nla_total_size(sizeof(struct nlattr));
 
-	list_for_each_entry(af_ops, &rtnl_af_ops, list) {
+	rcu_read_lock();
+	list_for_each_entry_rcu(af_ops, &rtnl_af_ops, list) {
 		if (af_ops->get_link_af_size) {
 			/* AF_* + nested data */
 			size += nla_total_size(sizeof(struct nlattr)) +
 				af_ops->get_link_af_size(dev, ext_filter_mask);
 		}
 	}
+	rcu_read_unlock();
 
 	return size;
 }
@@ -1382,6 +1386,47 @@ static int rtnl_fill_link_netnsid(struct sk_buff *skb,
 	return 0;
 }
 
+static int rtnl_fill_link_af(struct sk_buff *skb,
+			     const struct net_device *dev,
+			     u32 ext_filter_mask)
+{
+	const struct rtnl_af_ops *af_ops;
+	struct nlattr *af_spec;
+
+	af_spec = nla_nest_start(skb, IFLA_AF_SPEC);
+	if (!af_spec)
+		return -EMSGSIZE;
+
+	list_for_each_entry_rcu(af_ops, &rtnl_af_ops, list) {
+		struct nlattr *af;
+		int err;
+
+		if (!af_ops->fill_link_af)
+			continue;
+
+		af = nla_nest_start(skb, af_ops->family);
+		if (!af)
+			return -EMSGSIZE;
+
+		err = af_ops->fill_link_af(skb, dev, ext_filter_mask);
+		/*
+		 * Caller may return ENODATA to indicate that there
+		 * was no data to be dumped. This is not an error, it
+		 * means we should trim the attribute header and
+		 * continue.
+		 */
+		if (err == -ENODATA)
+			nla_nest_cancel(skb, af);
+		else if (err < 0)
+			return -EMSGSIZE;
+
+		nla_nest_end(skb, af);
+	}
+
+	nla_nest_end(skb, af_spec);
+	return 0;
+}
+
 static int rtnl_fill_ifinfo(struct sk_buff *skb, struct net_device *dev,
 			    int type, u32 pid, u32 seq, u32 change,
 			    unsigned int flags, u32 ext_filter_mask,
@@ -1389,8 +1434,6 @@ static int rtnl_fill_ifinfo(struct sk_buff *skb, struct net_device *dev,
 {
 	struct ifinfomsg *ifm;
 	struct nlmsghdr *nlh;
-	struct nlattr *af_spec;
-	struct rtnl_af_ops *af_ops;
 
 	ASSERT_RTNL();
 	nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ifm), flags);
@@ -1477,39 +1520,16 @@ static int rtnl_fill_ifinfo(struct sk_buff *skb, struct net_device *dev,
 	    nla_put_s32(skb, IFLA_NEW_NETNSID, *new_nsid) < 0)
 		goto nla_put_failure;
 
-	if (!(af_spec = nla_nest_start(skb, IFLA_AF_SPEC)))
-		goto nla_put_failure;
-
-	list_for_each_entry(af_ops, &rtnl_af_ops, list) {
-		if (af_ops->fill_link_af) {
-			struct nlattr *af;
-			int err;
-
-			if (!(af = nla_nest_start(skb, af_ops->family)))
-				goto nla_put_failure;
-
-			err = af_ops->fill_link_af(skb, dev, ext_filter_mask);
-
-			/*
-			 * Caller may return ENODATA to indicate that there
-			 * was no data to be dumped. This is not an error, it
-			 * means we should trim the attribute header and
-			 * continue.
-			 */
-			if (err == -ENODATA)
-				nla_nest_cancel(skb, af);
-			else if (err < 0)
-				goto nla_put_failure;
-
-			nla_nest_end(skb, af);
-		}
-	}
-
-	nla_nest_end(skb, af_spec);
+	rcu_read_lock();
+	if (rtnl_fill_link_af(skb, dev, ext_filter_mask))
+		goto nla_put_failure_rcu;
+	rcu_read_unlock();
 
 	nlmsg_end(skb, nlh);
 	return 0;
 
+nla_put_failure_rcu:
+	rcu_read_unlock();
 nla_put_failure:
 	nlmsg_cancel(skb, nlh);
 	return -EMSGSIZE;
@@ -1771,17 +1791,27 @@ static int validate_linkmsg(struct net_device *dev, struct nlattr *tb[])
 		nla_for_each_nested(af, tb[IFLA_AF_SPEC], rem) {
 			const struct rtnl_af_ops *af_ops;
 
-			if (!(af_ops = rtnl_af_lookup(nla_type(af))))
+			rcu_read_lock();
+			af_ops = rtnl_af_lookup(nla_type(af));
+			if (!af_ops) {
+				rcu_read_unlock();
 				return -EAFNOSUPPORT;
+			}
 
-			if (!af_ops->set_link_af)
+			if (!af_ops->set_link_af) {
+				rcu_read_unlock();
 				return -EOPNOTSUPP;
+			}
 
 			if (af_ops->validate_link_af) {
 				err = af_ops->validate_link_af(dev, af);
-				if (err < 0)
+				if (err < 0) {
+					rcu_read_unlock();
 					return err;
+				}
 			}
+
+			rcu_read_unlock();
 		}
 	}
 
@@ -2239,13 +2269,18 @@ static int do_setlink(const struct sk_buff *skb,
 		nla_for_each_nested(af, tb[IFLA_AF_SPEC], rem) {
 			const struct rtnl_af_ops *af_ops;
 
+			rcu_read_lock();
+
 			if (!(af_ops = rtnl_af_lookup(nla_type(af))))
 				BUG();
 
 			err = af_ops->set_link_af(dev, af);
-			if (err < 0)
+			if (err < 0) {
+				rcu_read_unlock();
 				goto errout;
+			}
 
+			rcu_read_unlock();
 			status |= DO_SETLINK_NOTIFY;
 		}
 	}
@@ -3066,21 +3101,21 @@ int ndo_dflt_fdb_add(struct ndmsg *ndm,
 }
 EXPORT_SYMBOL(ndo_dflt_fdb_add);
 
-static int fdb_vid_parse(struct nlattr *vlan_attr, u16 *p_vid)
+static int fdb_vid_parse(struct nlattr *vlan_attr, u16 *p_vid,
+			 struct netlink_ext_ack *extack)
 {
 	u16 vid = 0;
 
 	if (vlan_attr) {
 		if (nla_len(vlan_attr) != sizeof(u16)) {
-			pr_info("PF_BRIDGE: RTM_NEWNEIGH with invalid vlan\n");
+			NL_SET_ERR_MSG(extack, "invalid vlan attribute size");
 			return -EINVAL;
 		}
 
 		vid = nla_get_u16(vlan_attr);
 
 		if (!vid || vid >= VLAN_VID_MASK) {
-			pr_info("PF_BRIDGE: RTM_NEWNEIGH with invalid vlan id %d\n",
-				vid);
+			NL_SET_ERR_MSG(extack, "invalid vlan id");
 			return -EINVAL;
 		}
 	}
@@ -3105,24 +3140,24 @@ static int rtnl_fdb_add(struct sk_buff *skb, struct nlmsghdr *nlh,
 
 	ndm = nlmsg_data(nlh);
 	if (ndm->ndm_ifindex == 0) {
-		pr_info("PF_BRIDGE: RTM_NEWNEIGH with invalid ifindex\n");
+		NL_SET_ERR_MSG(extack, "invalid ifindex");
 		return -EINVAL;
 	}
 
 	dev = __dev_get_by_index(net, ndm->ndm_ifindex);
 	if (dev == NULL) {
-		pr_info("PF_BRIDGE: RTM_NEWNEIGH with unknown ifindex\n");
+		NL_SET_ERR_MSG(extack, "unknown ifindex");
 		return -ENODEV;
 	}
 
 	if (!tb[NDA_LLADDR] || nla_len(tb[NDA_LLADDR]) != ETH_ALEN) {
-		pr_info("PF_BRIDGE: RTM_NEWNEIGH with invalid address\n");
+		NL_SET_ERR_MSG(extack, "invalid address");
 		return -EINVAL;
 	}
 
 	addr = nla_data(tb[NDA_LLADDR]);
 
-	err = fdb_vid_parse(tb[NDA_VLAN], &vid);
+	err = fdb_vid_parse(tb[NDA_VLAN], &vid, extack);
 	if (err)
 		return err;
 
@@ -3209,24 +3244,24 @@ static int rtnl_fdb_del(struct sk_buff *skb, struct nlmsghdr *nlh,
 
 	ndm = nlmsg_data(nlh);
 	if (ndm->ndm_ifindex == 0) {
-		pr_info("PF_BRIDGE: RTM_DELNEIGH with invalid ifindex\n");
+		NL_SET_ERR_MSG(extack, "invalid ifindex");
 		return -EINVAL;
 	}
 
 	dev = __dev_get_by_index(net, ndm->ndm_ifindex);
 	if (dev == NULL) {
-		pr_info("PF_BRIDGE: RTM_DELNEIGH with unknown ifindex\n");
+		NL_SET_ERR_MSG(extack, "unknown ifindex");
 		return -ENODEV;
 	}
 
 	if (!tb[NDA_LLADDR] || nla_len(tb[NDA_LLADDR]) != ETH_ALEN) {
-		pr_info("PF_BRIDGE: RTM_DELNEIGH with invalid address\n");
+		NL_SET_ERR_MSG(extack, "invalid address");
 		return -EINVAL;
 	}
 
 	addr = nla_data(tb[NDA_LLADDR]);
 
-	err = fdb_vid_parse(tb[NDA_VLAN], &vid);
+	err = fdb_vid_parse(tb[NDA_VLAN], &vid, extack);
 	if (err)
 		return err;
 
@@ -3666,7 +3701,7 @@ static int rtnl_bridge_setlink(struct sk_buff *skb, struct nlmsghdr *nlh,
 
 	dev = __dev_get_by_index(net, ifm->ifi_index);
 	if (!dev) {
-		pr_info("PF_BRIDGE: RTM_SETLINK with unknown ifindex\n");
+		NL_SET_ERR_MSG(extack, "unknown ifindex");
 		return -ENODEV;
 	}
 
@@ -3741,7 +3776,7 @@ static int rtnl_bridge_dellink(struct sk_buff *skb, struct nlmsghdr *nlh,
 
 	dev = __dev_get_by_index(net, ifm->ifi_index);
 	if (!dev) {
-		pr_info("PF_BRIDGE: RTM_SETLINK with unknown ifindex\n");
+		NL_SET_ERR_MSG(extack, "unknown ifindex");
 		return -ENODEV;
 	}
 
@@ -3992,25 +4027,30 @@ static int rtnl_fill_statsinfo(struct sk_buff *skb, struct net_device *dev,
 		if (!attr)
 			goto nla_put_failure;
 
-		list_for_each_entry(af_ops, &rtnl_af_ops, list) {
+		rcu_read_lock();
+		list_for_each_entry_rcu(af_ops, &rtnl_af_ops, list) {
 			if (af_ops->fill_stats_af) {
 				struct nlattr *af;
 				int err;
 
 				af = nla_nest_start(skb, af_ops->family);
-				if (!af)
+				if (!af) {
+					rcu_read_unlock();
 					goto nla_put_failure;
-
+				}
 				err = af_ops->fill_stats_af(skb, dev);
 
-				if (err == -ENODATA)
+				if (err == -ENODATA) {
 					nla_nest_cancel(skb, af);
-				else if (err < 0)
+				} else if (err < 0) {
+					rcu_read_unlock();
 					goto nla_put_failure;
+				}
 
 				nla_nest_end(skb, af);
 			}
 		}
+		rcu_read_unlock();
 
 		nla_nest_end(skb, attr);
 
@@ -4079,7 +4119,8 @@ static size_t if_nlmsg_stats_size(const struct net_device *dev,
 		/* for IFLA_STATS_AF_SPEC */
 		size += nla_total_size(0);
 
-		list_for_each_entry(af_ops, &rtnl_af_ops, list) {
+		rcu_read_lock();
+		list_for_each_entry_rcu(af_ops, &rtnl_af_ops, list) {
 			if (af_ops->get_stats_af_size) {
 				size += nla_total_size(
 					af_ops->get_stats_af_size(dev));
@@ -4088,6 +4129,7 @@ static size_t if_nlmsg_stats_size(const struct net_device *dev,
 				size += nla_total_size(0);
 			}
 		}
+		rcu_read_unlock();
 	}
 
 	return size;