diff options
| author | Jim Westfall <jwestfall@surrealistic.net> | 2018-01-14 15:18:51 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-01-31 16:46:15 +0300 |
| commit | 6c16fa957e84c8b640dadc4e0264ff0d2dae7aa3 (patch) | |
| tree | de43c08f77704f2c6a49c40f0f7f5a5f99a7838d | |
| parent | fd3030090c8debb485d3867c17f691cf1af207f6 (diff) | |
| download | linux-6c16fa957e84c8b640dadc4e0264ff0d2dae7aa3.tar.xz | |
ipv4: Make neigh lookup keys for loopback/point-to-point devices be INADDR_ANY
[ Upstream commit cd9ff4de0107c65d69d02253bb25d6db93c3dbc1 ]
Map all lookup neigh keys to INADDR_ANY for loopback/point-to-point devices
to avoid making an entry for every remote ip the device needs to talk to.
This used the be the old behavior but became broken in a263b3093641f
(ipv4: Make neigh lookups directly in output packet path) and later removed
in 0bb4087cbec0 (ipv4: Fix neigh lookup keying over loopback/point-to-point
devices) because it was broken.
Signed-off-by: Jim Westfall <jwestfall@surrealistic.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | include/net/arp.h | 3 | ||||
| -rw-r--r-- | net/ipv4/arp.c | 7 |
2 files changed, 9 insertions, 1 deletions
diff --git a/include/net/arp.h b/include/net/arp.h index 73c49864076b..174014585ade 100644 --- a/include/net/arp.h +++ b/include/net/arp.h @@ -37,6 +37,9 @@ static inline struct neighbour *__ipv4_neigh_lookup(struct net_device *dev, u32 { struct neighbour *n; + if (dev->flags & (IFF_LOOPBACK | IFF_POINTOPOINT)) + key = INADDR_ANY; + rcu_read_lock_bh(); n = __ipv4_neigh_lookup_noref(dev, key); if (n && !atomic_inc_not_zero(&n->refcnt)) diff --git a/net/ipv4/arp.c b/net/ipv4/arp.c index 16acb59d665e..263729dea532 100644 --- a/net/ipv4/arp.c +++ b/net/ipv4/arp.c @@ -221,11 +221,16 @@ static u32 arp_hash(const void *pkey, static int arp_constructor(struct neighbour *neigh) { - __be32 addr = *(__be32 *)neigh->primary_key; + __be32 addr; struct net_device *dev = neigh->dev; struct in_device *in_dev; struct neigh_parms *parms; + u32 inaddr_any = INADDR_ANY; + if (dev->flags & (IFF_LOOPBACK | IFF_POINTOPOINT)) + memcpy(neigh->primary_key, &inaddr_any, arp_tbl.key_len); + + addr = *(__be32 *)neigh->primary_key; rcu_read_lock(); in_dev = __in_dev_get_rcu(dev); if (in_dev == NULL) { |