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2011-11-16tcp: clear xmit timers in tcp_v4_syn_recv_sock()Eric Dumazet
Simon Kirby reported divides by zero errors in __tcp_select_window() This happens when inet_csk_route_child_sock() returns a NULL pointer : We free new socket while we eventually armed keepalive timer in tcp_create_openreq_child() Fix this by a call to tcp_clear_xmit_timers() [ This is a followup to commit 918eb39962dff (net: add missing bh_unlock_sock() calls) ] Reported-by: Simon Kirby <sim@hostway.ca> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Tested-by: Simon Kirby <sim@hostway.ca> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-11-03net: add missing bh_unlock_sock() callsEric Dumazet
Simon Kirby reported lockdep warnings and following messages : [104661.897577] huh, entered softirq 3 NET_RX ffffffff81613740 preempt_count 00000101, exited with 00000102? [104661.923653] huh, entered softirq 3 NET_RX ffffffff81613740 preempt_count 00000101, exited with 00000102? Problem comes from commit 0e734419 (ipv4: Use inet_csk_route_child_sock() in DCCP and TCP.) If inet_csk_route_child_sock() returns NULL, we should release socket lock before freeing it. Another lock imbalance exists if __inet_inherit_port() returns an error since commit 093d282321da ( tproxy: fix hash locking issue when using port redirection in __inet_inherit_port()) a backport is also needed for >= 2.6.37 kernels. Reported-by: Simon Kirby <sim@hostway.ca> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Tested-by: Eric Dumazet <eric.dumazet@gmail.com> CC: Balazs Scheidler <bazsi@balabit.hu> CC: KOVACS Krisztian <hidden@balabit.hu> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Simon Kirby <sim@hostway.ca> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-11-01net: make the tcp and udp file_operations for the /proc stuff constArjan van de Ven
the tcp and udp code creates a set of struct file_operations at runtime while it can also be done at compile time, with the added benefit of then having these file operations be const. the trickiest part was to get the "THIS_MODULE" reference right; the naive method of declaring a struct in the place of registration would not work for this reason. Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-10-24ipv4: tcp: fix TOS value in ACK messages sent from TIME_WAITEric Dumazet
There is a long standing bug in linux tcp stack, about ACK messages sent on behalf of TIME_WAIT sockets. In the IP header of the ACK message, we choose to reflect TOS field of incoming message, and this might break some setups. Example of things that were broken : - Routing using TOS as a selector - Firewalls - Trafic classification / shaping We now remember in timewait structure the inet tos field and use it in ACK generation, and route lookup. Notes : - We still reflect incoming TOS in RST messages. - We could extend MuraliRaja Muniraju patch to report TOS value in netlink messages for TIME_WAIT sockets. - A patch is needed for IPv6 Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-10-24tcp: md5: add more const attributesEric Dumazet
Now tcp_md5_hash_header() has a const tcphdr argument, we can add more const attributes to callers. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-10-21tcp: add const qualifiers where possibleEric Dumazet
Adding const qualifiers to pointers can ease code review, and spot some bugs. It might allow compiler to optimize code further. For example, is it legal to temporary write a null cksum into tcphdr in tcp_md5_hash_header() ? I am afraid a sniffer could catch the temporary null value... Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-10-07Merge branch 'master' of github.com:davem330/netDavid S. Miller
Conflicts: net/batman-adv/soft-interface.c
2011-10-04tcp: properly handle md5sig_pool referencesYan, Zheng
tcp_v4_clear_md5_list() assumes that multiple tcp md5sig peers only hold one reference to md5sig_pool. but tcp_v4_md5_do_add() increases use count of md5sig_pool for each peer. This patch makes tcp_v4_md5_do_add() only increases use count for the first tcp md5sig peer. Signed-off-by: Zheng Yan <zheng.z.yan@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-09-27tcp: unalias tcp_skb_cb flags and ip_dsfieldEric Dumazet
struct tcp_skb_cb contains a "flags" field containing either tcp flags or IP dsfield depending on context (input or output path) Introduce ip_dsfield to make the difference clear and ease maintenance. If later we want to save space, we can union flags/ip_dsfield Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-09-22Merge branch 'master' of github.com:davem330/netDavid S. Miller
Conflicts: MAINTAINERS drivers/net/Kconfig drivers/net/ethernet/broadcom/bnx2x/bnx2x_link.c drivers/net/ethernet/broadcom/tg3.c drivers/net/wireless/iwlwifi/iwl-pci.c drivers/net/wireless/iwlwifi/iwl-trans-tx-pcie.c drivers/net/wireless/rt2x00/rt2800usb.c drivers/net/wireless/wl12xx/main.c
2011-09-15tcp: Change possible SYN flooding messagesEric Dumazet
"Possible SYN flooding on port xxxx " messages can fill logs on servers. Change logic to log the message only once per listener, and add two new SNMP counters to track : TCPReqQFullDoCookies : number of times a SYNCOOKIE was replied to client TCPReqQFullDrop : number of times a SYN request was dropped because syncookies were not enabled. Based on a prior patch from Tom Herbert, and suggestions from David. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> CC: Tom Herbert <therbert@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-08-17rps: Add flag to skb to indicate rxhash is based on L4 tupleTom Herbert
The l4_rxhash flag was added to the skb structure to indicate that the rxhash value was computed over the 4 tuple for the packet which includes the port information in the encapsulated transport packet. This is used by the stack to preserve the rxhash value in __skb_rx_tunnel. Signed-off-by: Tom Herbert <therbert@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-08-06net: Compute protocol sequence numbers and fragment IDs using MD5.David S. Miller
Computers have become a lot faster since we compromised on the partial MD4 hash which we use currently for performance reasons. MD5 is a much safer choice, and is inline with both RFC1948 and other ISS generators (OpenBSD, Solaris, etc.) Furthermore, only having 24-bits of the sequence number be truly unpredictable is a very serious limitation. So the periodic regeneration and 8-bit counter have been removed. We compute and use a full 32-bit sequence number. For ipv6, DCCP was found to use a 32-bit truncated initial sequence number (it needs 43-bits) and that is fixed here as well. Reported-by: Dan Kaminsky <dan@doxpara.com> Tested-by: Willy Tarreau <w@1wt.eu> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-06-20Merge branch 'master' of ↵David S. Miller
master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6 Conflicts: drivers/net/wireless/iwlwifi/iwl-agn-rxon.c drivers/net/wireless/rtlwifi/pci.c net/netfilter/ipvs/ip_vs_core.c
2011-06-17net: rfs: enable RFS before first data packet is receivedEric Dumazet
Le jeudi 16 juin 2011 à 23:38 -0400, David Miller a écrit : > From: Ben Hutchings <bhutchings@solarflare.com> > Date: Fri, 17 Jun 2011 00:50:46 +0100 > > > On Wed, 2011-06-15 at 04:15 +0200, Eric Dumazet wrote: > >> @@ -1594,6 +1594,7 @@ int tcp_v4_do_rcv(struct sock *sk, struct sk_buff *skb) > >> goto discard; > >> > >> if (nsk != sk) { > >> + sock_rps_save_rxhash(nsk, skb->rxhash); > >> if (tcp_child_process(sk, nsk, skb)) { > >> rsk = nsk; > >> goto reset; > >> > > > > I haven't tried this, but it looks reasonable to me. > > > > What about IPv6? The logic in tcp_v6_do_rcv() looks very similar. > > Indeed ipv6 side needs the same fix. > > Eric please add that part and resubmit. And in fact I might stick > this into net-2.6 instead of net-next-2.6 > OK, here is the net-2.6 based one then, thanks ! [PATCH v2] net: rfs: enable RFS before first data packet is received First packet received on a passive tcp flow is not correctly RFS steered. One sock_rps_record_flow() call is missing in inet_accept() But before that, we also must record rxhash when child socket is setup. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> CC: Tom Herbert <therbert@google.com> CC: Ben Hutchings <bhutchings@solarflare.com> CC: Jamal Hadi Salim <hadi@cyberus.ca> Signed-off-by: David S. Miller <davem@conan.davemloft.net>
2011-06-08tcp: RFC2988bis + taking RTT sample from 3WHS for the passive open sideJerry Chu
This patch lowers the default initRTO from 3secs to 1sec per RFC2988bis. It falls back to 3secs if the SYN or SYN-ACK packet has been retransmitted, AND the TCP timestamp option is not on. It also adds support to take RTT sample during 3WHS on the passive open side, just like its active open counterpart, and uses it, if valid, to seed the initRTO for the data transmission phase. The patch also resets ssthresh to its initial default at the beginning of the data transmission phase, and reduces cwnd to 1 if there has been MORE THAN ONE retransmission during 3WHS per RFC5681. Signed-off-by: H.K. Jerry Chu <hkchu@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-05-24net: convert %p usage to %pKDan Rosenberg
The %pK format specifier is designed to hide exposed kernel pointers, specifically via /proc interfaces. Exposing these pointers provides an easy target for kernel write vulnerabilities, since they reveal the locations of writable structures containing easily triggerable function pointers. The behavior of %pK depends on the kptr_restrict sysctl. If kptr_restrict is set to 0, no deviation from the standard %p behavior occurs. If kptr_restrict is set to 1, the default, if the current user (intended to be a reader via seq_printf(), etc.) does not have CAP_SYSLOG (currently in the LSM tree), kernel pointers using %pK are printed as 0's. If kptr_restrict is set to 2, kernel pointers using %pK are printed as 0's regardless of privileges. Replacing with 0's was chosen over the default "(null)", which cannot be parsed by userland %p, which expects "(nil)". The supporting code for kptr_restrict and %pK are currently in the -mm tree. This patch converts users of %p in net/ to %pK. Cases of printing pointers to the syslog are not covered, since this would eliminate useful information for postmortem debugging and the reading of the syslog is already optionally protected by the dmesg_restrict sysctl. Signed-off-by: Dan Rosenberg <drosenberg@vsecurity.com> Cc: James Morris <jmorris@namei.org> Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: Thomas Graf <tgraf@infradead.org> Cc: Eugene Teo <eugeneteo@kernel.org> Cc: Kees Cook <kees.cook@canonical.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: David S. Miller <davem@davemloft.net> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Eric Paris <eparis@parisplace.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-05-18ipv4: Pass explicit destination address to rt_bind_peer().David S. Miller
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-05-18ipv4: Pass explicit destination address to rt_get_peer().David S. Miller
This will next trickle down to rt_bind_peer(). Signed-off-by: David S. Miller <davem@davemloft.net>
2011-05-18ipv4: Make caller provide flowi4 key to inet_csk_route_req().David S. Miller
This way the caller can get at the fully resolved fl4->{daddr,saddr} etc. Signed-off-by: David S. Miller <davem@davemloft.net>
2011-05-10ipv4: Pass explicit daddr arg to ip_send_reply().David S. Miller
This eliminates an access to rt->rt_src. Signed-off-by: David S. Miller <davem@davemloft.net>
2011-05-08tcp: Use cork flow info instead of rt->rt_dst in tcp_v4_get_peer()David S. Miller
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-05-08ipv4: Use inet_csk_route_child_sock() in DCCP and TCP.David S. Miller
Operation order is now transposed, we first create the child socket then we try to hook up the route. Signed-off-by: David S. Miller <davem@davemloft.net>
2011-05-08tcp: Use cork flow in tcp_v4_connect()David S. Miller
Since this is invoked from inet_stream_connect() the socket is locked and therefore this usage is safe. Signed-off-by: David S. Miller <davem@davemloft.net>
2011-04-28ipv4: Get route daddr from flow key in tcp_v4_connect().David S. Miller
Now that output route lookups update the flow with destination address selection, we can fetch it from fl4->daddr instead of rt->rt_dst Signed-off-by: David S. Miller <davem@davemloft.net>
2011-04-28ipv4: Fetch route saddr from flow key in tcp_v4_connect().David S. Miller
Now that output route lookups update the flow with source address selection, we can fetch it from fl4->saddr instead of rt->rt_src Signed-off-by: David S. Miller <davem@davemloft.net>
2011-04-28inet: add RCU protection to inet->optEric Dumazet
We lack proper synchronization to manipulate inet->opt ip_options Problem is ip_make_skb() calls ip_setup_cork() and ip_setup_cork() possibly makes a copy of ipc->opt (struct ip_options), without any protection against another thread manipulating inet->opt. Another thread can change inet->opt pointer and free old one under us. Use RCU to protect inet->opt (changed to inet->inet_opt). Instead of handling atomic refcounts, just copy ip_options when necessary, to avoid cache line dirtying. We cant insert an rcu_head in struct ip_options since its included in skb->cb[], so this patch is large because I had to introduce a new ip_options_rcu structure. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Cc: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-04-27ipv4: Sanitize and simplify ip_route_{connect,newports}()David S. Miller
These functions are used together as a unit for route resolution during connect(). They address the chicken-and-egg problem that exists when ports need to be allocated during connect() processing, yet such port allocations require addressing information from the routing code. It's currently more heavy handed than it needs to be, and in particular we allocate and initialize a flow object twice. Let the callers provide the on-stack flow object. That way we only need to initialize it once in the ip_route_connect() call. Later, if ip_route_newports() needs to do anything, it re-uses that flow object as-is except for the ports which it updates before the route re-lookup. Also, describe why this set of facilities are needed and how it works in a big comment. Signed-off-by: David S. Miller <davem@davemloft.net> Reviewed-by: Eric Dumazet <eric.dumazet@gmail.com>
2011-04-22inet: constify ip headers and in6_addrEric Dumazet
Add const qualifiers to structs iphdr, ipv6hdr and in6_addr pointers where possible, to make code intention more obvious. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-02ipv4: Make output route lookup return rtable directly.David S. Miller
Instead of on the stack. Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-01ipv4: Can final ip_route_connect() arg to boolean "can_sleep".David S. Miller
Since that's what the current vague "flags" thing means. Signed-off-by: David S. Miller <davem@davemloft.net>
2011-02-24ipv4: Rearrange how ip_route_newports() gets port keys.David S. Miller
ip_route_newports() is the only place in the entire kernel that cares about the port members in the routing cache entry's lookup flow key. Therefore the only reason we store an entire flow inside of the struct rtentry is for this one special case. Rewrite ip_route_newports() such that: 1) The caller passes in the original port values, so we don't need to use the rth->fl.fl_ip_{s,d}port values to remember them. 2) The lookup flow is constructed by hand instead of being copied from the routing cache entry's flow. Signed-off-by: David S. Miller <davem@davemloft.net>
2011-02-20tcp: Remove debug macro of TCP_CHECK_TIMERShan Wei
Now, TCP_CHECK_TIMER is not used for debuging, it does nothing. And, it has been there for several years, maybe 6 years. Remove it to keep code clearer. Signed-off-by: Shan Wei <shanwei@cn.fujitsu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-02-10inetpeer: Abstract address representation further.David S. Miller
Future changes will add caching information, and some of these new elements will be addresses. Since the family is implicit via the ->daddr.family member, replicating the family in ever address we store is entirely redundant. Signed-off-by: David S. Miller <davem@davemloft.net>
2011-01-24tcp: fix bug in listening_get_next()Eric Dumazet
commit a8b690f98baf9fb19 (tcp: Fix slowness in read /proc/net/tcp) introduced a bug in handling of SYN_RECV sockets. st->offset represents number of sockets found since beginning of listening_hash[st->bucket]. We should not reset st->offset when iterating through syn_table[st->sbucket], or else if more than ~25 sockets (if PAGE_SIZE=4096) are in SYN_RECV state, we exit from listening_get_next() with a too small st->offset Next time we enter tcp_seek_last_pos(), we are not able to seek past already found sockets. Reported-by: PK <runningdoglackey@yahoo.com> CC: Tom Herbert <therbert@google.com> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-12-26Merge branch 'master' of ↵David S. Miller
master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6 Conflicts: net/ipv4/fib_frontend.c
2010-12-23tcp: fix listening_get_next()Eric Dumazet
Alexey Vlasov found /proc/net/tcp could sometime loop and display millions of sockets in LISTEN state. In 2.6.29, when we converted TCP hash tables to RCU, we left two sk_next() calls in listening_get_next(). We must instead use sk_nulls_next() to properly detect an end of chain. Reported-by: Alexey Vlasov <renton@renton.name> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-12-13net: Abstract default ADVMSS behind an accessor.David S. Miller
Make all RTAX_ADVMSS metric accesses go through a new helper function, dst_metric_advmss(). Leave the actual default metric as "zero" in the real metric slot, and compute the actual default value dynamically via a new dst_ops AF specific callback. For stacked IPSEC routes, we use the advmss of the path which preserves existing behavior. Unlike ipv4/ipv6, DecNET ties the advmss to the mtu and thus updates advmss on pmtu updates. This inconsistency in advmss handling results in more raw metric accesses than I wish we ended up with. Signed-off-by: David S. Miller <davem@davemloft.net>
2010-12-08Merge branch 'master' of ↵David S. Miller
master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6 Conflicts: drivers/net/wireless/ath/ath9k/ar9003_eeprom.c net/llc/af_llc.c
2010-12-01timewait_sock: Create and use getpeer op.David S. Miller
The only thing AF-specific about remembering the timestamp for a time-wait TCP socket is getting the peer. Abstract that behind a new timewait_sock_ops vector. Support for real IPV6 sockets is not filled in yet, but curiously this makes timewait recycling start to work for v4-mapped ipv6 sockets. Signed-off-by: David S. Miller <davem@davemloft.net>
2010-11-30inet: Turn ->remember_stamp into ->get_peer in connection AF ops.David S. Miller
Then we can make a completely generic tcp_remember_stamp() that uses ->get_peer() as a helper, minimizing the AF specific code and minimizing the eventual code duplication when we implement the ipv6 side of TW recycling. Signed-off-by: David S. Miller <davem@davemloft.net>
2010-11-30inetpeer: Make inet_getpeer() take an inet_peer_adress_t pointer.David S. Miller
And make an inet_getpeer_v4() helper, update callers. Signed-off-by: David S. Miller <davem@davemloft.net>
2010-11-30inetpeer: Introduce inet_peer_address_t.David S. Miller
Currently only the v4 aspect is used, but this will change. Signed-off-by: David S. Miller <davem@davemloft.net>
2010-11-27netns: Don't leak others' openreq-s in procPavel Emelyanov
The /proc/net/tcp leaks openreq sockets from other namespaces. Signed-off-by: Pavel Emelyanov <xemul@parallels.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-11-12tcp: Don't change unlocked socket state in tcp_v4_err().David S. Miller
Alexey Kuznetsov noticed a regression introduced by commit f1ecd5d9e7366609d640ff4040304ea197fbc618 ("Revert Backoff [v3]: Revert RTO on ICMP destination unreachable") The RTO and timer modification code added to tcp_v4_err() doesn't check sock_owned_by_user(), which if true means we don't have exclusive access to the socket and therefore cannot modify it's critical state. Just skip this new code block if sock_owned_by_user() is true and eliminate the now superfluous sock_owned_by_user() code block contained within. Reported-by: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru> Signed-off-by: David S. Miller <davem@davemloft.net> CC: Damian Lukowski <damian@tvk.rwth-aachen.de> Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
2010-10-21tproxy: fix hash locking issue when using port redirection in ↵Balazs Scheidler
__inet_inherit_port() When __inet_inherit_port() is called on a tproxy connection the wrong locks are held for the inet_bind_bucket it is added to. __inet_inherit_port() made an implicit assumption that the listener's port number (and thus its bind bucket). Unfortunately, if you're using the TPROXY target to redirect skbs to a transparent proxy that assumption is not true anymore and things break. This patch adds code to __inet_inherit_port() so that it can handle this case by looking up or creating a new bind bucket for the child socket and updates callers of __inet_inherit_port() to gracefully handle __inet_inherit_port() failing. Reported by and original patch from Stephen Buck <stephen.buck@exinda.com>. See http://marc.info/?t=128169268200001&r=1&w=2 for the original discussion. Signed-off-by: KOVACS Krisztian <hidden@balabit.hu> Signed-off-by: Patrick McHardy <kaber@trash.net>
2010-08-31gro: unexport tcp4_gro_receive and tcp4_gro_completeEric Dumazet
tcp4_gro_receive() and tcp4_gro_complete() dont need to be exported. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-07-12inet, inet6: make tcp_sendmsg() and tcp_sendpage() through inet_sendmsg() ↵Changli Gao
and inet_sendpage() a new boolean flag no_autobind is added to structure proto to avoid the autobind calls when the protocol is TCP. Then sock_rps_record_flow() is called int the TCP's sendmsg() and sendpage() pathes. Signed-off-by: Changli Gao <xiaosuo@gmail.com> ---- include/net/inet_common.h | 4 ++++ include/net/sock.h | 1 + include/net/tcp.h | 8 ++++---- net/ipv4/af_inet.c | 15 +++++++++------ net/ipv4/tcp.c | 11 +++++------ net/ipv4/tcp_ipv4.c | 3 +++ net/ipv6/af_inet6.c | 8 ++++---- net/ipv6/tcp_ipv6.c | 3 +++ 8 files changed, 33 insertions(+), 20 deletions(-) Signed-off-by: David S. Miller <davem@davemloft.net>
2010-07-12net/ipv4: EXPORT_SYMBOL cleanupsEric Dumazet
CodingStyle cleanups EXPORT_SYMBOL should immediately follow the symbol declaration. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-06-26syncookies: add support for ECNFlorian Westphal
Allows use of ECN when syncookies are in effect by encoding ecn_ok into the syn-ack tcp timestamp. While at it, remove a uneeded #ifdef CONFIG_SYN_COOKIES. With CONFIG_SYN_COOKIES=nm want_cookie is ifdef'd to 0 and gcc removes the "if (0)". Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: David S. Miller <davem@davemloft.net>