[PATCH 3.4 044/125] net/neighbour: fix crash at dumping device-agnostic proxy entries

From: lizf
Date: Wed Oct 12 2016 - 08:46:42 EST


From: Konstantin Khlebnikov <koct9i@xxxxxxxxx>

3.4.113-rc1 review patch. If anyone has any objections, please let me know.

------------------


commit 6adc5fd6a142c6e2c80574c1db0c7c17dedaa42e upstream.

Proxy entries could have null pointer to net-device.

Signed-off-by: Konstantin Khlebnikov <koct9i@xxxxxxxxx>
Fixes: 84920c1420e2 ("net: Allow ipv6 proxies and arp proxies be shown with iproute2")
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
[lizf: Backported to 3.4: adjust context]
Signed-off-by: Zefan Li <lizefan@xxxxxxxxxx>
---
net/core/neighbour.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/net/core/neighbour.c b/net/core/neighbour.c
index ebd4b21..dbd00df 100644
--- 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;
--
1.9.1