neighbor: Add extack messages for add and delete commands

Add extack messages for failures in neigh_add and neigh_delete.

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/core/neighbour.c b/net/core/neighbour.c
index 41954e42a2ded2ac1770c4b107505a5eee57a2be..6d479b5562bea737cd8d7a6363a5f5455069e699 100644 (file)
--- a/net/core/neighbour.c
+++ b/net/core/neighbour.c
@@ -1137,8 +1137,9 @@ static void neigh_update_hhs(struct neighbour *neigh)
    Caller MUST hold reference count on the entry.
  */
 
-int neigh_update(struct neighbour *neigh, const u8 *lladdr, u8 new,
-                u32 flags, u32 nlmsg_pid)
+static int __neigh_update(struct neighbour *neigh, const u8 *lladdr,
+                         u8 new, u32 flags, u32 nlmsg_pid,
+                         struct netlink_ext_ack *extack)
 {
        u8 old;
        int err;
@@ -1155,8 +1156,10 @@ int neigh_update(struct neighbour *neigh, const u8 *lladdr, u8 new,
        if (!(flags & NEIGH_UPDATE_F_ADMIN) &&
            (old & (NUD_NOARP | NUD_PERMANENT)))
                goto out;
-       if (neigh->dead)
+       if (neigh->dead) {
+               NL_SET_ERR_MSG(extack, "Neighbor entry is now dead");
                goto out;
+       }
 
        neigh_update_ext_learned(neigh, flags, &notify);
 
@@ -1193,8 +1196,10 @@ int neigh_update(struct neighbour *neigh, const u8 *lladdr, u8 new,
                   use it, otherwise discard the request.
                 */
                err = -EINVAL;
-               if (!(old & NUD_VALID))
+               if (!(old & NUD_VALID)) {
+                       NL_SET_ERR_MSG(extack, "No link layer address given");
                        goto out;
+               }
                lladdr = neigh->ha;
        }
 
@@ -1307,6 +1312,12 @@ out:
 
        return err;
 }
+
+int neigh_update(struct neighbour *neigh, const u8 *lladdr, u8 new,
+                u32 flags, u32 nlmsg_pid)
+{
+       return __neigh_update(neigh, lladdr, new, flags, nlmsg_pid, NULL);
+}
 EXPORT_SYMBOL(neigh_update);
 
 /* Update the neigh to listen temporarily for probe responses, even if it is
@@ -1678,8 +1689,10 @@ static int neigh_delete(struct sk_buff *skb, struct nlmsghdr *nlh,
                goto out;
 
        dst_attr = nlmsg_find_attr(nlh, sizeof(*ndm), NDA_DST);
-       if (dst_attr == NULL)
+       if (!dst_attr) {
+               NL_SET_ERR_MSG(extack, "Network address not specified");
                goto out;
+       }
 
        ndm = nlmsg_data(nlh);
        if (ndm->ndm_ifindex) {
@@ -1694,8 +1707,10 @@ static int neigh_delete(struct sk_buff *skb, struct nlmsghdr *nlh,
        if (tbl == NULL)
                return -EAFNOSUPPORT;
 
-       if (nla_len(dst_attr) < (int)tbl->key_len)
+       if (nla_len(dst_attr) < (int)tbl->key_len) {
+               NL_SET_ERR_MSG(extack, "Invalid network address");
                goto out;
+       }
 
        if (ndm->ndm_flags & NTF_PROXY) {
                err = pneigh_delete(tbl, net, nla_data(dst_attr), dev);
@@ -1711,10 +1726,9 @@ static int neigh_delete(struct sk_buff *skb, struct nlmsghdr *nlh,
                goto out;
        }
 
-       err = neigh_update(neigh, NULL, NUD_FAILED,
-                          NEIGH_UPDATE_F_OVERRIDE |
-                          NEIGH_UPDATE_F_ADMIN,
-                          NETLINK_CB(skb).portid);
+       err = __neigh_update(neigh, NULL, NUD_FAILED,
+                            NEIGH_UPDATE_F_OVERRIDE | NEIGH_UPDATE_F_ADMIN,
+                            NETLINK_CB(skb).portid, extack);
        write_lock_bh(&tbl->lock);
        neigh_release(neigh);
        neigh_remove_one(neigh, tbl);
@@ -1744,8 +1758,10 @@ static int neigh_add(struct sk_buff *skb, struct nlmsghdr *nlh,
                goto out;
 
        err = -EINVAL;
-       if (tb[NDA_DST] == NULL)
+       if (!tb[NDA_DST]) {
+               NL_SET_ERR_MSG(extack, "Network address not specified");
                goto out;
+       }
 
        ndm = nlmsg_data(nlh);
        if (ndm->ndm_ifindex) {
@@ -1755,16 +1771,21 @@ static int neigh_add(struct sk_buff *skb, struct nlmsghdr *nlh,
                        goto out;
                }
 
-               if (tb[NDA_LLADDR] && nla_len(tb[NDA_LLADDR]) < dev->addr_len)
+               if (tb[NDA_LLADDR] && nla_len(tb[NDA_LLADDR]) < dev->addr_len) {
+                       NL_SET_ERR_MSG(extack, "Invalid link address");
                        goto out;
+               }
        }
 
        tbl = neigh_find_table(ndm->ndm_family);
        if (tbl == NULL)
                return -EAFNOSUPPORT;
 
-       if (nla_len(tb[NDA_DST]) < (int)tbl->key_len)
+       if (nla_len(tb[NDA_DST]) < (int)tbl->key_len) {
+               NL_SET_ERR_MSG(extack, "Invalid network address");
                goto out;
+       }
+
        dst = nla_data(tb[NDA_DST]);
        lladdr = tb[NDA_LLADDR] ? nla_data(tb[NDA_LLADDR]) : NULL;
 
@@ -1780,8 +1801,10 @@ static int neigh_add(struct sk_buff *skb, struct nlmsghdr *nlh,
                goto out;
        }
 
-       if (dev == NULL)
+       if (!dev) {
+               NL_SET_ERR_MSG(extack, "Device not specified");
                goto out;
+       }
 
        neigh = neigh_lookup(tbl, dst, dev);
        if (neigh == NULL) {
@@ -1817,8 +1840,8 @@ static int neigh_add(struct sk_buff *skb, struct nlmsghdr *nlh,
                neigh_event_send(neigh, NULL);
                err = 0;
        } else
-               err = neigh_update(neigh, lladdr, ndm->ndm_state, flags,
-                                  NETLINK_CB(skb).portid);
+               err = __neigh_update(neigh, lladdr, ndm->ndm_state, flags,
+                                    NETLINK_CB(skb).portid, extack);
        neigh_release(neigh);
 
 out: