net/neighbour: fix crash at dumping device-agnostic proxy entries

commit 6adc5fd6a142c6e2c80574c1db0c7c17dedaa42e upstream.

Proxy entries could have null pointer to net-device.

Signed-off-by: Konstantin Khlebnikov <koct9i@gmail.com>
Fixes: 84920c1420e2 ("net: Allow ipv6 proxies and arp proxies be shown with iproute2")
Signed-off-by: David S. Miller <davem@davemloft.net>
[lizf: Backported to 3.4: adjust context]
Signed-off-by: Zefan Li <lizefan@huawei.com>

diff --git a/net/core/neighbour.c b/net/core/neighbour.c
index ebd4b21cb9d453945529628d8b8e5737735f2838..dbd00dfbc6ce75d8063d6b3f71ebf3db85002ba9 100644 (file)
--- a/net/core/neighbour.c
+++ b/net/core/neighbour.c
@@ -2186,7 +2186,7 @@ static int pneigh_fill_info(struct sk_buff *skb, struct pneigh_entry *pn,
        ndm->ndm_pad2    = 0;
        ndm->ndm_flags   = pn->flags | NTF_PROXY;
        ndm->ndm_type    = NDA_DST;
-       ndm->ndm_ifindex = pn->dev->ifindex;
+       ndm->ndm_ifindex = pn->dev ? pn->dev->ifindex : 0;
        ndm->ndm_state   = NUD_NONE;
 
        NLA_PUT(skb, NDA_DST, tbl->key_len, pn->key);
@@ -2259,7 +2259,7 @@ static int pneigh_dump_table(struct neigh_table *tbl, struct sk_buff *skb,
                if (h > s_h)
                        s_idx = 0;
                for (n = tbl->phash_buckets[h], idx = 0; n; n = n->next) {
-                       if (dev_net(n->dev) != net)
+                       if (pneigh_net(n) != net)
                                continue;
                        if (idx < s_idx)
                                goto next;