| Message ID | 20111019160537.4aeedef8@asterix.rh |
|---|---|
| State | Changes Requested, archived |
| Delegated to: | David Miller |
| Headers | show |
On Wed, 19 Oct 2011 16:05:37 -0200 Flavio Leitner <fbl@redhat.com> wrote: > On Mon, 17 Oct 2011 19:43:44 -0400 (EDT) > David Miller <davem@davemloft.net> wrote: > > > From: Flavio Leitner <fbl@redhat.com> > > Date: Wed, 5 Oct 2011 11:20:04 -0300 > > > > > The commit f39925dbde7788cfb96419c0f092b086aa325c0f > > > (ipv4: Cache learned redirect information in inetpeer.) > > > removed some ICMP packet validations which are required by > > > RFC 1122, section 3.2.2.2: > > > > The reason for putting this into the inetpeer cache was so that we > > didn't need to consult the routing cache at all. We're working to > > remove it at some point, so every dependency matters. > > > > Can you implement this such that only an inetpeer cache probe is > > necessary? > > > > Sure, I have reviewed your patch series to remove the routing > cache and I believe this version works with and without it, though > I have tested only with current net-next code. > > Thanks for your time reviewing, I appreciate it. ... > @@ -1331,13 +1337,40 @@ void ip_rt_redirect(__be32 old_gw, __be32 daddr, __be32 new_gw, > goto reject_redirect; > } > > - peer = inet_getpeer_v4(daddr, 1); > - if (peer) { > - peer->redirect_learned.a4 = new_gw; > + memset(&fl4, 0, sizeof(fl4)); > + fl4.daddr = daddr; > + for (s = 0; s < 2; s++) { > + for (i = 0; i < 2; i++) { > + fl4.flowi4_oif = ikeys[i]; > + fl4.saddr = skeys[s]; > + rt = __ip_route_output_key(net, &fl4); > + if (IS_ERR(rt)) > + continue; > > - inet_putpeer(peer); > + if (rt->dst.error || rt->dst.dev != dev || > + rt->rt_gateway != old_gw) { > + ip_rt_put(rt); > + continue; > + } > > - atomic_inc(&__rt_peer_genid); > + peer = rt->peer; > + if (!peer) { > + peer = inet_getpeer_v4(daddr, 1); > + putpeer = true; > + } I was reviewing this again and instead of doing the above, it would be better to use rt_bind_peer() to update rt->peer as well. if (!rt->peer) rt_bind_peer(rt, rt->rt_dst, 1); peer = rt->peer; if (peer) { peer->redirect_learned.a4 = new_gw; atomic_inc(&__rt_peer_genid); } but I am not sure if I understood you completely when you say to do such that only an inetpeer cache probe is necessary. thanks again, fbl -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
From: Flavio Leitner <fbl@redhat.com> Date: Thu, 20 Oct 2011 15:47:02 -0200 > I was reviewing this again and instead of doing the above, it would > be better to use rt_bind_peer() to update rt->peer as well. > > if (!rt->peer) > rt_bind_peer(rt, rt->rt_dst, 1); > > peer = rt->peer; > if (peer) { > peer->redirect_learned.a4 = new_gw; > atomic_inc(&__rt_peer_genid); > } > > > but I am not sure if I understood you completely when you say > to do such that only an inetpeer cache probe is necessary. If you have the route entry available already and you're doing the inetpeer lookup anyways, you might as well use rt_bind_peer() since all of the expensive work has to be done anyways. So yes, using rt_bind_peer() would be the best thing to do here. -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Thu, 20 Oct 2011 16:19:29 -0400 (EDT) David Miller <davem@davemloft.net> wrote: > From: Flavio Leitner <fbl@redhat.com> > Date: Thu, 20 Oct 2011 15:47:02 -0200 > > > I was reviewing this again and instead of doing the above, it would > > be better to use rt_bind_peer() to update rt->peer as well. > > > > if (!rt->peer) > > rt_bind_peer(rt, rt->rt_dst, 1); > > > > peer = rt->peer; > > if (peer) { > > peer->redirect_learned.a4 = new_gw; > > atomic_inc(&__rt_peer_genid); > > } > > > > > > but I am not sure if I understood you completely when you say > > to do such that only an inetpeer cache probe is necessary. > > If you have the route entry available already and you're doing the > inetpeer lookup anyways, you might as well use rt_bind_peer() since > all of the expensive work has to be done anyways. > > So yes, using rt_bind_peer() would be the best thing to do here. > just posted patch v3. iirc, you prefer to receive patches as new posts rather than replies to old threads. "Subject: [PATCH net-next v3] route: fix ICMP redirect validation" thanks again, fbl -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/net/ipv4/route.c b/net/ipv4/route.c index 26c77e1..1a639b9 100644 --- a/net/ipv4/route.c +++ b/net/ipv4/route.c @@ -1308,8 +1308,14 @@ static void rt_del(unsigned hash, struct rtable *rt) void ip_rt_redirect(__be32 old_gw, __be32 daddr, __be32 new_gw, __be32 saddr, struct net_device *dev) { + int s, i; struct in_device *in_dev = __in_dev_get_rcu(dev); + struct rtable *rt; + __be32 skeys[2] = { saddr, 0 }; + int ikeys[2] = { dev->ifindex, 0 }; + struct flowi4 fl4; struct inet_peer *peer; + bool putpeer = false; struct net *net; if (!in_dev) @@ -1331,13 +1337,40 @@ void ip_rt_redirect(__be32 old_gw, __be32 daddr, __be32 new_gw, goto reject_redirect; } - peer = inet_getpeer_v4(daddr, 1); - if (peer) { - peer->redirect_learned.a4 = new_gw; + memset(&fl4, 0, sizeof(fl4)); + fl4.daddr = daddr; + for (s = 0; s < 2; s++) { + for (i = 0; i < 2; i++) { + fl4.flowi4_oif = ikeys[i]; + fl4.saddr = skeys[s]; + rt = __ip_route_output_key(net, &fl4); + if (IS_ERR(rt)) + continue; - inet_putpeer(peer); + if (rt->dst.error || rt->dst.dev != dev || + rt->rt_gateway != old_gw) { + ip_rt_put(rt); + continue; + } - atomic_inc(&__rt_peer_genid); + peer = rt->peer; + if (!peer) { + peer = inet_getpeer_v4(daddr, 1); + putpeer = true; + } + + if (peer) { + peer->redirect_learned.a4 = new_gw; + + if (putpeer) + inet_putpeer(peer); + + atomic_inc(&__rt_peer_genid); + } + + ip_rt_put(rt); + return; + } } return;