diff options
| author | Eric Dumazet <edumazet@google.com> | 2017-03-23 12:39:21 -0700 |
|---|---|---|
| committer | Sasha Levin <alexander.levin@verizon.com> | 2017-06-13 09:29:18 -0400 |
| commit | b39245e33e95813bd25ffd3166c8788834ffd904 (patch) | |
| tree | 42fe29705b01274fce85d249503b704be2d1b7fc /net | |
| parent | 9ffb20a699469e8de9c44e61b28d0b70354127a4 (diff) | |
net: neigh: guard against NULL solicit() method
[ Upstream commit 48481c8fa16410ffa45939b13b6c53c2ca609e5f ]
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>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
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 d6e8cfcb6f7c..cb9a7ab5444c 100644 --- a/net/core/neighbour.c +++ b/net/core/neighbour.c @@ -855,7 +855,8 @@ static void neigh_probe(struct neighbour *neigh) if (skb) skb = skb_copy(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); } |