1 files changed, 59 insertions, 21 deletions

diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index 65aebd450027..f965dce6f20f 100644
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -60,7 +60,6 @@ struct rtnl_link {
 };
 
 static DEFINE_MUTEX(rtnl_mutex);
-static u16 min_ifinfo_dump_size;
 
 void rtnl_lock(void)
 {
@@ -724,10 +723,11 @@ static void copy_rtnl_link_stats64(void *v, const struct rtnl_link_stats64 *b)
 }
 
 /* All VF info */
-static inline int rtnl_vfinfo_size(const struct net_device *dev)
+static inline int rtnl_vfinfo_size(const struct net_device *dev,
+                                   u32 ext_filter_mask)
 {
-        if (dev->dev.parent && dev_is_pci(dev->dev.parent)) {
-
+        if (dev->dev.parent && dev_is_pci(dev->dev.parent) &&
+            (ext_filter_mask & RTEXT_FILTER_VF)) {
                 int num_vfs = dev_num_vf(dev->dev.parent);
                 size_t size = nla_total_size(sizeof(struct nlattr));
                 size += nla_total_size(num_vfs * sizeof(struct nlattr));
@@ -766,7 +766,8 @@ static size_t rtnl_port_size(const struct net_device *dev)
                 return port_self_size;
 }
 
-static noinline size_t if_nlmsg_size(const struct net_device *dev)
+static noinline size_t if_nlmsg_size(const struct net_device *dev,
+                                     u32 ext_filter_mask)
 {
         return NLMSG_ALIGN(sizeof(struct ifinfomsg))
                + nla_total_size(IFNAMSIZ) /* IFLA_IFNAME */
@@ -784,8 +785,9 @@ static noinline size_t if_nlmsg_size(const struct net_device *dev)
                + nla_total_size(4) /* IFLA_MASTER */
                + nla_total_size(1) /* IFLA_OPERSTATE */
                + nla_total_size(1) /* IFLA_LINKMODE */
-               + nla_total_size(4) /* IFLA_NUM_VF */
-               + rtnl_vfinfo_size(dev) /* IFLA_VFINFO_LIST */
+               + nla_total_size(ext_filter_mask
+                                & RTEXT_FILTER_VF ? 4 : 0) /* IFLA_NUM_VF */
+               + rtnl_vfinfo_size(dev, ext_filter_mask) /* IFLA_VFINFO_LIST */
                + rtnl_port_size(dev) /* IFLA_VF_PORTS + IFLA_PORT_SELF */
                + rtnl_link_get_size(dev) /* IFLA_LINKINFO */
                + rtnl_link_get_af_size(dev); /* IFLA_AF_SPEC */
@@ -868,7 +870,7 @@ static int rtnl_port_fill(struct sk_buff *skb, struct net_device *dev)
 
 static int rtnl_fill_ifinfo(struct sk_buff *skb, struct net_device *dev,
                             int type, u32 pid, u32 seq, u32 change,
-                            unsigned int flags)
+                            unsigned int flags, u32 ext_filter_mask)
 {
         struct ifinfomsg *ifm;
         struct nlmsghdr *nlh;
@@ -941,10 +943,11 @@ static int rtnl_fill_ifinfo(struct sk_buff *skb, struct net_device *dev,
                 goto nla_put_failure;
         copy_rtnl_link_stats64(nla_data(attr), stats);
 
-        if (dev->dev.parent)
+        if (dev->dev.parent && (ext_filter_mask & RTEXT_FILTER_VF))
                 NLA_PUT_U32(skb, IFLA_NUM_VF, dev_num_vf(dev->dev.parent));
 
-        if (dev->netdev_ops->ndo_get_vf_config && dev->dev.parent) {
+        if (dev->netdev_ops->ndo_get_vf_config && dev->dev.parent
+            && (ext_filter_mask & RTEXT_FILTER_VF)) {
                 int i;
 
                 struct nlattr *vfinfo, *vf;
@@ -1048,6 +1051,8 @@ static int rtnl_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
         struct net_device *dev;
         struct hlist_head *head;
         struct hlist_node *node;
+        struct nlattr *tb[IFLA_MAX+1];
+        u32 ext_filter_mask = 0;
 
         s_h = cb->args[0];
         s_idx = cb->args[1];
@@ -1055,6 +1060,13 @@ static int rtnl_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
         rcu_read_lock();
         cb->seq = net->dev_base_seq;
 
+        if (nlmsg_parse(cb->nlh, sizeof(struct rtgenmsg), tb, IFLA_MAX,
+                        ifla_policy) >= 0) {
+
+                if (tb[IFLA_EXT_MASK])
+                        ext_filter_mask = nla_get_u32(tb[IFLA_EXT_MASK]);
+        }
+
         for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
                 idx = 0;
                 head = &net->dev_index_head[h];
@@ -1064,7 +1076,8 @@ static int rtnl_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
                         if (rtnl_fill_ifinfo(skb, dev, RTM_NEWLINK,
                                              NETLINK_CB(cb->skb).pid,
                                              cb->nlh->nlmsg_seq, 0,
-                                             NLM_F_MULTI) <= 0)
+                                             NLM_F_MULTI,
+                                             ext_filter_mask) <= 0)
                                 goto out;
 
                         nl_dump_check_consistent(cb, nlmsg_hdr(skb));
@@ -1100,6 +1113,7 @@ const struct nla_policy ifla_policy[IFLA_MAX+1] = {
         [IFLA_VF_PORTS]         = { .type = NLA_NESTED },
         [IFLA_PORT_SELF]        = { .type = NLA_NESTED },
         [IFLA_AF_SPEC]          = { .type = NLA_NESTED },
+        [IFLA_EXT_MASK]         = { .type = NLA_U32 },
 };
 EXPORT_SYMBOL(ifla_policy);
 
@@ -1509,8 +1523,6 @@ errout:
 
         if (send_addr_notify)
                 call_netdevice_notifiers(NETDEV_CHANGEADDR, dev);
-        min_ifinfo_dump_size = max_t(u16, if_nlmsg_size(dev),
-                                     min_ifinfo_dump_size);
 
         return err;
 }
@@ -1842,6 +1854,7 @@ static int rtnl_getlink(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
         struct net_device *dev = NULL;
         struct sk_buff *nskb;
         int err;
+        u32 ext_filter_mask = 0;
 
         err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFLA_MAX, ifla_policy);
         if (err < 0)
@@ -1850,6 +1863,9 @@ static int rtnl_getlink(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
         if (tb[IFLA_IFNAME])
                 nla_strlcpy(ifname, tb[IFLA_IFNAME], IFNAMSIZ);
 
+        if (tb[IFLA_EXT_MASK])
+                ext_filter_mask = nla_get_u32(tb[IFLA_EXT_MASK]);
+
         ifm = nlmsg_data(nlh);
         if (ifm->ifi_index > 0)
                 dev = __dev_get_by_index(net, ifm->ifi_index);
@@ -1861,12 +1877,12 @@ static int rtnl_getlink(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
         if (dev == NULL)
                 return -ENODEV;
 
-        nskb = nlmsg_new(if_nlmsg_size(dev), GFP_KERNEL);
+        nskb = nlmsg_new(if_nlmsg_size(dev, ext_filter_mask), GFP_KERNEL);
         if (nskb == NULL)
                 return -ENOBUFS;
 
         err = rtnl_fill_ifinfo(nskb, dev, RTM_NEWLINK, NETLINK_CB(skb).pid,
-                               nlh->nlmsg_seq, 0, 0);
+                               nlh->nlmsg_seq, 0, 0, ext_filter_mask);
         if (err < 0) {
                 /* -EMSGSIZE implies BUG in if_nlmsg_size */
                 WARN_ON(err == -EMSGSIZE);
@@ -1877,8 +1893,32 @@ static int rtnl_getlink(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
         return err;
 }
 
-static u16 rtnl_calcit(struct sk_buff *skb)
+static u16 rtnl_calcit(struct sk_buff *skb, struct nlmsghdr *nlh)
 {
+        struct net *net = sock_net(skb->sk);
+        struct net_device *dev;
+        struct nlattr *tb[IFLA_MAX+1];
+        u32 ext_filter_mask = 0;
+        u16 min_ifinfo_dump_size = 0;
+
+        if (nlmsg_parse(nlh, sizeof(struct rtgenmsg), tb, IFLA_MAX,
+                        ifla_policy) >= 0) {
+                if (tb[IFLA_EXT_MASK])
+                        ext_filter_mask = nla_get_u32(tb[IFLA_EXT_MASK]);
+        }
+
+        if (!ext_filter_mask)
+                return NLMSG_GOODSIZE;
+        /*
+         * traverse the list of net devices and compute the minimum
+         * buffer size based upon the filter mask.
+         */
+        list_for_each_entry(dev, &net->dev_base_head, dev_list) {
+                min_ifinfo_dump_size = max_t(u16, min_ifinfo_dump_size,
+                                             if_nlmsg_size(dev,
+                                                           ext_filter_mask));
+        }
+
         return min_ifinfo_dump_size;
 }
 
@@ -1913,13 +1953,11 @@ void rtmsg_ifinfo(int type, struct net_device *dev, unsigned change)
         int err = -ENOBUFS;
         size_t if_info_size;
 
-        skb = nlmsg_new((if_info_size = if_nlmsg_size(dev)), GFP_KERNEL);
+        skb = nlmsg_new((if_info_size = if_nlmsg_size(dev, 0)), GFP_KERNEL);
         if (skb == NULL)
                 goto errout;
 
-        min_ifinfo_dump_size = max_t(u16, if_info_size, min_ifinfo_dump_size);
-
-        err = rtnl_fill_ifinfo(skb, dev, type, 0, 0, change, 0);
+        err = rtnl_fill_ifinfo(skb, dev, type, 0, 0, change, 0, 0);
         if (err < 0) {
                 /* -EMSGSIZE implies BUG in if_nlmsg_size() */
                 WARN_ON(err == -EMSGSIZE);
@@ -1977,7 +2015,7 @@ static int rtnetlink_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
                         return -EOPNOTSUPP;
                 calcit = rtnl_get_calcit(family, type);
                 if (calcit)
-                        min_dump_alloc = calcit(skb);
+                        min_dump_alloc = calcit(skb, nlh);
 
                 __rtnl_unlock();
                 rtnl = net->rtnl;