diff options
| author | Eric Dumazet <edumazet@google.com> | 2017-03-23 12:39:21 -0700 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2017-03-23 21:28:13 -0700 |
| commit | 48481c8fa16410ffa45939b13b6c53c2ca609e5f (patch) | |
| tree | f5cfccdad2c1fec0ac88053fd1e8299c0b7dc44b /net | |
| parent | f35ec35e5e726e7137deaee0dec24f8cbf07a48f (diff) | |
net: neigh: guard against NULL solicit() method
Dmitry posted a nice reproducer of a bug triggering in neigh_probe()
when dereferencing a NULL neigh->ops->solicit method.
This can happen for arp_direct_ops/ndisc_direct_ops and similar,
which can be used for NUD_NOARP neighbours (created when dev->header_ops
is NULL). Admin can then force changing nud_state to some other state
that would fire neigh timer.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net')
| -rw-r--r-- | net/core/neighbour.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/net/core/neighbour.c b/net/core/neighbour.c index e7c12caa20c8..4526cbd7e28a 100644 --- a/net/core/neighbour.c +++ b/net/core/neighbour.c @@ -860,7 +860,8 @@ static void neigh_probe(struct neighbour *neigh) if (skb) skb = skb_clone(skb, GFP_ATOMIC); write_unlock(&neigh->lock); - neigh->ops->solicit(neigh, skb); + if (neigh->ops->solicit) + neigh->ops->solicit(neigh, skb); atomic_inc(&neigh->probes); kfree_skb(skb); } |