Please apply the following patches to 3.0.x-stable and 3.2.x-stable

There are two mbox fixes, one for 3.0.x and one for 3.2.x

Thanks.
>From 0a00912df20e6b30404d5fc25d7f4e839c812849 Mon Sep 17 00:00:00 2001
From: Eric Dumazet <[email protected]>
Date: Sat, 10 Mar 2012 09:20:21 +0000
Subject: [PATCH 1/2] tcp: fix syncookie regression

[ Upstream commit dfd25ffffc132c00070eed64200e8950da5d7e9d ]

commit ea4fc0d619 (ipv4: Don't use rt->rt_{src,dst} in ip_queue_xmit())
added a serious regression on synflood handling.

Simon Kirby discovered a successful connection was delayed by 20 seconds
before being responsive.

In my tests, I discovered that xmit frames were lost, and needed ~4
retransmits and a socket dst rebuild before being really sent.

In case of syncookie initiated connection, we use a different path to
initialize the socket dst, and inet->cork.fl.u.ip4 is left cleared.

As ip_queue_xmit() now depends on inet flow being setup, fix this by
copying the temp flowi4 we use in cookie_v4_check().

Reported-by: Simon Kirby <[email protected]>
Bisected-by: Simon Kirby <[email protected]>
Signed-off-by: Eric Dumazet <[email protected]>
Tested-by: Eric Dumazet <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
---
 net/ipv4/syncookies.c |   30 ++++++++++++++++--------------
 net/ipv4/tcp_ipv4.c   |   10 +++++++---
 2 files changed, 23 insertions(+), 17 deletions(-)

diff --git a/net/ipv4/syncookies.c b/net/ipv4/syncookies.c
index 4382629..895f215 100644
--- a/net/ipv4/syncookies.c
+++ b/net/ipv4/syncookies.c
@@ -277,6 +277,7 @@ struct sock *cookie_v4_check(struct sock *sk, struct 
sk_buff *skb,
        struct rtable *rt;
        __u8 rcv_wscale;
        bool ecn_ok = false;
+       struct flowi4 fl4;
 
        if (!sysctl_tcp_syncookies || !th->ack || th->rst)
                goto out;
@@ -344,20 +345,16 @@ struct sock *cookie_v4_check(struct sock *sk, struct 
sk_buff *skb,
         * hasn't changed since we received the original syn, but I see
         * no easy way to do this.
         */
-       {
-               struct flowi4 fl4;
-
-               flowi4_init_output(&fl4, 0, sk->sk_mark, RT_CONN_FLAGS(sk),
-                                  RT_SCOPE_UNIVERSE, IPPROTO_TCP,
-                                  inet_sk_flowi_flags(sk),
-                                  (opt && opt->srr) ? opt->faddr : 
ireq->rmt_addr,
-                                  ireq->loc_addr, th->source, th->dest);
-               security_req_classify_flow(req, flowi4_to_flowi(&fl4));
-               rt = ip_route_output_key(sock_net(sk), &fl4);
-               if (IS_ERR(rt)) {
-                       reqsk_free(req);
-                       goto out;
-               }
+       flowi4_init_output(&fl4, 0, sk->sk_mark, RT_CONN_FLAGS(sk),
+                          RT_SCOPE_UNIVERSE, IPPROTO_TCP,
+                          inet_sk_flowi_flags(sk),
+                          (opt && opt->srr) ? opt->faddr : ireq->rmt_addr,
+                          ireq->loc_addr, th->source, th->dest);
+       security_req_classify_flow(req, flowi4_to_flowi(&fl4));
+       rt = ip_route_output_key(sock_net(sk), &fl4);
+       if (IS_ERR(rt)) {
+               reqsk_free(req);
+               goto out;
        }
 
        /* Try to redo what tcp_v4_send_synack did. */
@@ -371,5 +368,10 @@ struct sock *cookie_v4_check(struct sock *sk, struct 
sk_buff *skb,
        ireq->rcv_wscale  = rcv_wscale;
 
        ret = get_cookie_sock(sk, skb, req, &rt->dst);
+       /* ip_queue_xmit() depends on our flow being setup
+        * Normal sockets get it right from inet_csk_route_child_sock()
+        */
+       if (ret)
+               inet_sk(ret)->cork.fl.u.ip4 = fl4;
 out:   return ret;
 }
diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index 04c6592..53a5af6 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -1454,9 +1454,13 @@ struct sock *tcp_v4_syn_recv_sock(struct sock *sk, 
struct sk_buff *skb,
                inet_csk(newsk)->icsk_ext_hdr_len = inet_opt->opt.optlen;
        newinet->inet_id = newtp->write_seq ^ jiffies;
 
-       if (!dst && (dst = inet_csk_route_child_sock(sk, newsk, req)) == NULL)
-               goto put_and_exit;
-
+       if (!dst) {
+               dst = inet_csk_route_child_sock(sk, newsk, req);
+               if (!dst)
+                       goto put_and_exit;
+       } else {
+               /* syncookie case : see end of cookie_v4_check() */
+       }
        sk_setup_caps(newsk, dst);
 
        tcp_mtup_init(newsk);
-- 
1.7.7.6


>From af00059acc17645d97b2966bbb091a6ca0fba858 Mon Sep 17 00:00:00 2001
From: "RongQing.Li" <[email protected]>
Date: Thu, 15 Mar 2012 22:54:14 +0000
Subject: [PATCH 2/2] ipv6: Don't dev_hold(dev) in ip6_mc_find_dev_rcu.

[ Upstream commit c577923756b7fe9071f28a76b66b83b306d1d001 ]

ip6_mc_find_dev_rcu() is called with rcu_read_lock(), so don't
need to dev_hold().
With dev_hold(), not corresponding dev_put(), will lead to leak.

[ bug introduced in 96b52e61be1 (ipv6: mcast: RCU conversions) ]

Signed-off-by: RongQing.Li <[email protected]>
Acked-by: Eric Dumazet <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
---
 net/ipv6/mcast.c |    1 -
 1 files changed, 0 insertions(+), 1 deletions(-)

diff --git a/net/ipv6/mcast.c b/net/ipv6/mcast.c
index ee7839f..2257366 100644
--- a/net/ipv6/mcast.c
+++ b/net/ipv6/mcast.c
@@ -257,7 +257,6 @@ static struct inet6_dev *ip6_mc_find_dev_rcu(struct net 
*net,
 
                if (rt) {
                        dev = rt->rt6i_dev;
-                       dev_hold(dev);
                        dst_release(&rt->dst);
                }
        } else
-- 
1.7.7.6

>From 3e9eb20e6f5e649c43be81677248c86a8e7b3961 Mon Sep 17 00:00:00 2001
From: Eric Dumazet <[email protected]>
Date: Sat, 10 Mar 2012 09:20:21 +0000
Subject: [PATCH 1/2] tcp: fix syncookie regression

[ Upstream commit dfd25ffffc132c00070eed64200e8950da5d7e9d ]

commit ea4fc0d619 (ipv4: Don't use rt->rt_{src,dst} in ip_queue_xmit())
added a serious regression on synflood handling.

Simon Kirby discovered a successful connection was delayed by 20 seconds
before being responsive.

In my tests, I discovered that xmit frames were lost, and needed ~4
retransmits and a socket dst rebuild before being really sent.

In case of syncookie initiated connection, we use a different path to
initialize the socket dst, and inet->cork.fl.u.ip4 is left cleared.

As ip_queue_xmit() now depends on inet flow being setup, fix this by
copying the temp flowi4 we use in cookie_v4_check().

Reported-by: Simon Kirby <[email protected]>
Bisected-by: Simon Kirby <[email protected]>
Signed-off-by: Eric Dumazet <[email protected]>
Tested-by: Eric Dumazet <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
---
 net/ipv4/syncookies.c |   30 ++++++++++++++++--------------
 net/ipv4/tcp_ipv4.c   |   10 +++++++---
 2 files changed, 23 insertions(+), 17 deletions(-)

diff --git a/net/ipv4/syncookies.c b/net/ipv4/syncookies.c
index 90f6544..769c0e9 100644
--- a/net/ipv4/syncookies.c
+++ b/net/ipv4/syncookies.c
@@ -278,6 +278,7 @@ struct sock *cookie_v4_check(struct sock *sk, struct 
sk_buff *skb,
        struct rtable *rt;
        __u8 rcv_wscale;
        bool ecn_ok = false;
+       struct flowi4 fl4;
 
        if (!sysctl_tcp_syncookies || !th->ack || th->rst)
                goto out;
@@ -346,20 +347,16 @@ struct sock *cookie_v4_check(struct sock *sk, struct 
sk_buff *skb,
         * hasn't changed since we received the original syn, but I see
         * no easy way to do this.
         */
-       {
-               struct flowi4 fl4;
-
-               flowi4_init_output(&fl4, 0, sk->sk_mark, RT_CONN_FLAGS(sk),
-                                  RT_SCOPE_UNIVERSE, IPPROTO_TCP,
-                                  inet_sk_flowi_flags(sk),
-                                  (opt && opt->srr) ? opt->faddr : 
ireq->rmt_addr,
-                                  ireq->loc_addr, th->source, th->dest);
-               security_req_classify_flow(req, flowi4_to_flowi(&fl4));
-               rt = ip_route_output_key(sock_net(sk), &fl4);
-               if (IS_ERR(rt)) {
-                       reqsk_free(req);
-                       goto out;
-               }
+       flowi4_init_output(&fl4, 0, sk->sk_mark, RT_CONN_FLAGS(sk),
+                          RT_SCOPE_UNIVERSE, IPPROTO_TCP,
+                          inet_sk_flowi_flags(sk),
+                          (opt && opt->srr) ? opt->faddr : ireq->rmt_addr,
+                          ireq->loc_addr, th->source, th->dest);
+       security_req_classify_flow(req, flowi4_to_flowi(&fl4));
+       rt = ip_route_output_key(sock_net(sk), &fl4);
+       if (IS_ERR(rt)) {
+               reqsk_free(req);
+               goto out;
        }
 
        /* Try to redo what tcp_v4_send_synack did. */
@@ -373,5 +370,10 @@ struct sock *cookie_v4_check(struct sock *sk, struct 
sk_buff *skb,
        ireq->rcv_wscale  = rcv_wscale;
 
        ret = get_cookie_sock(sk, skb, req, &rt->dst);
+       /* ip_queue_xmit() depends on our flow being setup
+        * Normal sockets get it right from inet_csk_route_child_sock()
+        */
+       if (ret)
+               inet_sk(ret)->cork.fl.u.ip4 = fl4;
 out:   return ret;
 }
diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index eb90aa8..de69cec 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -1465,9 +1465,13 @@ struct sock *tcp_v4_syn_recv_sock(struct sock *sk, 
struct sk_buff *skb,
                inet_csk(newsk)->icsk_ext_hdr_len = inet_opt->opt.optlen;
        newinet->inet_id = newtp->write_seq ^ jiffies;
 
-       if (!dst && (dst = inet_csk_route_child_sock(sk, newsk, req)) == NULL)
-               goto put_and_exit;
-
+       if (!dst) {
+               dst = inet_csk_route_child_sock(sk, newsk, req);
+               if (!dst)
+                       goto put_and_exit;
+       } else {
+               /* syncookie case : see end of cookie_v4_check() */
+       }
        sk_setup_caps(newsk, dst);
 
        tcp_mtup_init(newsk);
-- 
1.7.7.6


>From 83a87eb0683a5166845b7ea0cb236eab039f693b Mon Sep 17 00:00:00 2001
From: "RongQing.Li" <[email protected]>
Date: Thu, 15 Mar 2012 22:54:14 +0000
Subject: [PATCH 2/2] ipv6: Don't dev_hold(dev) in ip6_mc_find_dev_rcu.

[ Upstream commit c577923756b7fe9071f28a76b66b83b306d1d001 ]

ip6_mc_find_dev_rcu() is called with rcu_read_lock(), so don't
need to dev_hold().
With dev_hold(), not corresponding dev_put(), will lead to leak.

[ bug introduced in 96b52e61be1 (ipv6: mcast: RCU conversions) ]

Signed-off-by: RongQing.Li <[email protected]>
Acked-by: Eric Dumazet <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
---
 net/ipv6/mcast.c |    1 -
 1 files changed, 0 insertions(+), 1 deletions(-)

diff --git a/net/ipv6/mcast.c b/net/ipv6/mcast.c
index ee7839f..2257366 100644
--- a/net/ipv6/mcast.c
+++ b/net/ipv6/mcast.c
@@ -257,7 +257,6 @@ static struct inet6_dev *ip6_mc_find_dev_rcu(struct net 
*net,
 
                if (rt) {
                        dev = rt->rt6i_dev;
-                       dev_hold(dev);
                        dst_release(&rt->dst);
                }
        } else
-- 
1.7.7.6

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