This is a note to let you know that I've just added the patch titled

    net-tcp: fastopen: fix high order allocations

to the 3.13-stable tree which can be found at:
    
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     net-tcp-fastopen-fix-high-order-allocations.patch
and it can be found in the queue-3.13 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From foo@baz Wed Mar 19 23:31:33 Local time zone must be set--see zic manual 
>page 2014
From: Eric Dumazet <eduma...@google.com>
Date: Thu, 20 Feb 2014 10:09:18 -0800
Subject: net-tcp: fastopen: fix high order allocations

From: Eric Dumazet <eduma...@google.com>

[ Upstream commit f5ddcbbb40aa0ba7fbfe22355d287603dbeeaaac ]

This patch fixes two bugs in fastopen :

1) The tcp_sendmsg(...,  @size) argument was ignored.

   Code was relying on user not fooling the kernel with iovec mismatches

2) When MTU is about 64KB, tcp_send_syn_data() attempts order-5
allocations, which are likely to fail when memory gets fragmented.

Fixes: 783237e8daf13 ("net-tcp: Fast Open client - sending SYN-data")
Signed-off-by: Eric Dumazet <eduma...@google.com>
Cc: Yuchung Cheng <ych...@google.com>
Acked-by: Yuchung Cheng <ych...@google.com>
Tested-by: Yuchung Cheng <ych...@google.com>
Signed-off-by: David S. Miller <da...@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>
---
 include/net/tcp.h     |    3 ++-
 net/ipv4/tcp.c        |    8 +++++---
 net/ipv4/tcp_output.c |    7 ++++++-
 3 files changed, 13 insertions(+), 5 deletions(-)

--- a/include/net/tcp.h
+++ b/include/net/tcp.h
@@ -1312,7 +1312,8 @@ struct tcp_fastopen_request {
        /* Fast Open cookie. Size 0 means a cookie request */
        struct tcp_fastopen_cookie      cookie;
        struct msghdr                   *data;  /* data in MSG_FASTOPEN */
-       u16                             copied; /* queued in tcp_connect() */
+       size_t                          size;
+       int                             copied; /* queued in tcp_connect() */
 };
 void tcp_free_fastopen_req(struct tcp_sock *tp);
 
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -1002,7 +1002,8 @@ void tcp_free_fastopen_req(struct tcp_so
        }
 }
 
-static int tcp_sendmsg_fastopen(struct sock *sk, struct msghdr *msg, int *size)
+static int tcp_sendmsg_fastopen(struct sock *sk, struct msghdr *msg,
+                               int *copied, size_t size)
 {
        struct tcp_sock *tp = tcp_sk(sk);
        int err, flags;
@@ -1017,11 +1018,12 @@ static int tcp_sendmsg_fastopen(struct s
        if (unlikely(tp->fastopen_req == NULL))
                return -ENOBUFS;
        tp->fastopen_req->data = msg;
+       tp->fastopen_req->size = size;
 
        flags = (msg->msg_flags & MSG_DONTWAIT) ? O_NONBLOCK : 0;
        err = __inet_stream_connect(sk->sk_socket, msg->msg_name,
                                    msg->msg_namelen, flags);
-       *size = tp->fastopen_req->copied;
+       *copied = tp->fastopen_req->copied;
        tcp_free_fastopen_req(tp);
        return err;
 }
@@ -1041,7 +1043,7 @@ int tcp_sendmsg(struct kiocb *iocb, stru
 
        flags = msg->msg_flags;
        if (flags & MSG_FASTOPEN) {
-               err = tcp_sendmsg_fastopen(sk, msg, &copied_syn);
+               err = tcp_sendmsg_fastopen(sk, msg, &copied_syn, size);
                if (err == -EINPROGRESS && copied_syn > 0)
                        goto out;
                else if (err)
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -2887,7 +2887,12 @@ static int tcp_send_syn_data(struct sock
        space = __tcp_mtu_to_mss(sk, inet_csk(sk)->icsk_pmtu_cookie) -
                MAX_TCP_OPTION_SPACE;
 
-       syn_data = skb_copy_expand(syn, skb_headroom(syn), space,
+       space = min_t(size_t, space, fo->size);
+
+       /* limit to order-0 allocations */
+       space = min_t(size_t, space, SKB_MAX_HEAD(MAX_TCP_HEADER));
+
+       syn_data = skb_copy_expand(syn, MAX_TCP_HEADER, space,
                                   sk->sk_allocation);
        if (syn_data == NULL)
                goto fallback;


Patches currently in stable-queue which might be from eduma...@google.com are

queue-3.13/net-tcp-fastopen-fix-high-order-allocations.patch
queue-3.13/sch_tbf-fix-potential-memory-leak-in-tbf_change.patch
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