1 files changed, 12 insertions, 5 deletions

diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index 64ad17d077ed..8db72ac88feb 100644
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -1198,6 +1198,7 @@ static int rtnl_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
         struct hlist_head *head;
         struct nlattr *tb[IFLA_MAX+1];
         u32 ext_filter_mask = 0;
+        int err;
 
         s_h = cb->args[0];
         s_idx = cb->args[1];
@@ -1218,11 +1219,17 @@ static int rtnl_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
                 hlist_for_each_entry_rcu(dev, head, index_hlist) {
                         if (idx < s_idx)
                                 goto cont;
-                        if (rtnl_fill_ifinfo(skb, dev, RTM_NEWLINK,
-                                             NETLINK_CB(cb->skb).portid,
-                                             cb->nlh->nlmsg_seq, 0,
-                                             NLM_F_MULTI,
-                                             ext_filter_mask) <= 0)
+                        err = rtnl_fill_ifinfo(skb, dev, RTM_NEWLINK,
+                                               NETLINK_CB(cb->skb).portid,
+                                               cb->nlh->nlmsg_seq, 0,
+                                               NLM_F_MULTI,
+                                               ext_filter_mask);
+                        /* If we ran out of room on the first message,
+                         * we're in trouble
+                         */
+                        WARN_ON((err == -EMSGSIZE) && (skb->len == 0));
+
+                        if (err <= 0)
                                 goto out;
 
                         nl_dump_check_consistent(cb, nlmsg_hdr(skb));