diff options
| author | Jim Westfall <jwestfall@surrealistic.net> | 2018-01-14 04:18:51 -0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-01-31 12:06:14 +0100 |
| commit | cab8451486a6fd9ba4ce798d41352f45abb44fae (patch) | |
| tree | 025b4974c9fcc62345e72424a0ce4b919dd84c41 | |
| parent | 29837a4a8764c1b73674eb78c99717cbc73aa9f3 (diff) | |
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 5e0f891d476c..1b3f86981757 100644 --- a/include/net/arp.h +++ b/include/net/arp.h @@ -19,6 +19,9 @@ static inline u32 arp_hashfn(const void *pkey, const struct net_device *dev, u32 static inline struct neighbour *__ipv4_neigh_lookup_noref(struct net_device *dev, u32 key) { + if (dev->flags & (IFF_LOOPBACK | IFF_POINTOPOINT)) + key = INADDR_ANY; + return ___neigh_lookup_noref(&arp_tbl, neigh_key_eq32, arp_hashfn, &key, dev); } diff --git a/net/ipv4/arp.c b/net/ipv4/arp.c index 711b4dfa17c3..cb5eb649ad5f 100644 --- a/net/ipv4/arp.c +++ b/net/ipv4/arp.c @@ -223,11 +223,16 @@ static bool arp_key_eq(const struct neighbour *neigh, 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) { |