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2011-12-12per-netns ipv4 sysctl_tcp_memGlauber Costa1-9/+2
This patch allows each namespace to independently set up its levels for tcp memory pressure thresholds. This patch alone does not buy much: we need to make this values per group of process somehow. This is achieved in the patches that follows in this patchset. Signed-off-by: Glauber Costa <glommer@parallels.com> Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> CC: David S. Miller <davem@davemloft.net> CC: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-12-05tcp: remove TCP_OFF and TCP_PAGE macrosEric Dumazet1-13/+10
As mentioned by Joe Perches, TCP_OFF() and TCP_PAGE() macros are useless. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-12-04tcp: tcp_sendmsg() page recyclingEric Dumazet1-1/+6
If our TCP_PAGE(sk) is not shared (page_count() == 1), we can set page offset to 0. This permits better filling of the pages on small to medium tcp writes. "tbench 16" results on my dev server (2x4x2 machine) : Before : 3072 MB/s After : 3146 MB/s (2.4 % gain) Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-11-29tcp: avoid frag allocation for small framesEric Dumazet1-3/+6
tcp_sendmsg() uses select_size() helper to choose skb head size when a new skb must be allocated. If GSO is enabled for the socket, current strategy is to force all payload data to be outside of headroom, in PAGE fragments. This strategy is not welcome for small packets, wasting memory. Experiments show that best results are obtained when using 2048 bytes for skb head (This includes the skb overhead and various headers) This patch provides better len/truesize ratios for packets sent to loopback device, and reduce memory needs for in-flight loopback packets, particularly on arches with big pages. If a sender sends many 1-byte packets to an unresponsive application, receiver rmem_alloc will grow faster and will stop queuing these packets sooner, or will collapse its receive queue to free excess memory. netperf -t TCP_RR results are improved by ~4 %, and many workloads are improved as well (tbench, mysql...) Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-11-28tcp: tcp_sendmsg() wrong access to sk_route_capsEric Dumazet1-4/+4
Now sk_route_caps is u64, its dangerous to use an integer to store result of an AND operator. It wont work if NETIF_F_SG is moved on the upper part of u64. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> CC: Michał Mirosław <mirq-linux@rere.qmqm.pl> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-11-16net: introduce and use netdev_features_t for device features setsMichał Mirosław1-1/+2
v2: add couple missing conversions in drivers split unexporting netdev_fix_features() implemented %pNF convert sock::sk_route_(no?)caps Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-10-24TCP: remove TCP_DEBUGFlavio Leitner1-2/+0
It was enabled by default and the messages guarded by the define are useful. Signed-off-by: Flavio Leitner <fbl@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-10-24tcp: md5: dont write skb head in tcp_md5_hash_header()Eric Dumazet1-6/+8
tcp_md5_hash_header() writes into skb header a temporary zero value, this might confuse other users of this area. Since tcphdr is small (20 bytes), copy it in a temporary variable and make the change in the copy. 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 Dumazet1-9/+9
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>
2011-10-19net: add skb frag size accessorsEric Dumazet1-5/+4
To ease skb->truesize sanitization, its better to be able to localize all references to skb frags size. Define accessors : skb_frag_size() to fetch frag size, and skb_frag_size_{set|add|sub}() to manipulate it. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-10-03tcp: report ECN_SEEN in tcp_infoEric Dumazet1-1/+3
Allows ss command (iproute2) to display "ecnseen" if at least one packet with ECT(0) or ECT(1) or ECN was received by this socket. "ecn" means ECN was negotiated at session establishment (TCP level) "ecnseen" means we received at least one packet with ECT fields set (IP level) ss -i ... ESTAB 0 0 192.168.20.110:22 192.168.20.144:38016 ino:5950 sk:f178e400 mem:(r0,w0,f0,t0) ts sack ecn ecnseen bic wscale:7,8 rto:210 rtt:12.5/7.5 cwnd:10 send 9.3Mbps rcv_space:14480 Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-09-27tcp: rename tcp_skb_cb flagsEric Dumazet1-4/+4
Rename struct tcp_skb_cb "flags" to "tcp_flags" to ease code review and maintenance. Its content is a combination of FIN/SYN/RST/PSH/ACK/URG/ECE/CWR flags Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-09-17tcp: md5: remove one indirection level in tcp_md5sig_poolEric Dumazet1-24/+17
tcp_md5sig_pool is currently an 'array' (a percpu object) of pointers to struct tcp_md5sig_pool. Only the pointers are NUMA aware, but objects themselves are all allocated on a single node. Remove this extra indirection to get proper percpu memory (NUMA aware) and make code simpler. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-08-24net: ipv4: convert to SKB frag APIsIan Campbell1-1/+2
Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru> Cc: "Pekka Savola (ipv6)" <pekkas@netcore.fi> Cc: James Morris <jmorris@namei.org> Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org> Cc: Patrick McHardy <kaber@trash.net> Cc: netdev@vger.kernel.org Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-07net: refine {udp|tcp|sctp}_mem limitsEric Dumazet1-8/+2
Current tcp/udp/sctp global memory limits are not taking into account hugepages allocations, and allow 50% of ram to be used by buffers of a single protocol [ not counting space used by sockets / inodes ...] Lets use nr_free_buffer_pages() and allow a default of 1/8 of kernel ram per protocol, and a minimum of 128 pages. Heavy duty machines sysadmins probably need to tweak limits anyway. References: https://bugzilla.stlinux.com/show_bug.cgi?id=38032 Reported-by: starlight <starlight@binnacle.cx> Suggested-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-04-04net: Allow no-cache copy from user on transmitTom Herbert1-3/+4
This patch uses __copy_from_user_nocache on transmit to bypass data cache for a performance improvement. skb_add_data_nocache and skb_copy_to_page_nocache can be called by sendmsg functions to use this feature, initial support is in tcp_sendmsg. This functionality is configurable per device using ethtool. Presumably, this feature would only be useful when the driver does not touch the data. The feature is turned on by default if a device indicates that it does some form of checksum offload; it is off by default for devices that do no checksum offload or indicate no checksum is necessary. For the former case copy-checksum is probably done anyway, in the latter case the device is likely loopback in which case the no cache copy is probably not beneficial. This patch was tested using 200 instances of netperf TCP_RR with 1400 byte request and one byte reply. Platform is 16 core AMD x86. No-cache copy disabled: 672703 tps, 97.13% utilization 50/90/99% latency:244.31 484.205 1028.41 No-cache copy enabled: 702113 tps, 96.16% utilization, 50/90/99% latency 238.56 467.56 956.955 Using 14000 byte request and response sizes demonstrate the effects more dramatically: No-cache copy disabled: 79571 tps, 34.34 %utlization 50/90/95% latency 1584.46 2319.59 5001.76 No-cache copy enabled: 83856 tps, 34.81% utilization 50/90/95% latency 2508.42 2622.62 2735.88 Note especially the effect on latency tail (95th percentile). This seems to provide a nice performance improvement and is consistent in the tests I ran. Presumably, this would provide the greatest benfits in the presence of an application workload stressing the cache and a lot of transmit data happening. Signed-off-by: Tom Herbert <therbert@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-09tcp: ioctl type SIOCOUTQNSD returns amount of data not sentMario Schuknecht1-0/+9
In contrast to SIOCOUTQ which returns the amount of data sent but not yet acknowledged plus data not yet sent this patch only returns the data not sent. For various methods of live streaming bitrate control it may be helpful to know how much data are in the tcp outqueue are not sent yet. Signed-off-by: Mario Schuknecht <m.schuknecht@dresearch.de> Signed-off-by: Steffen Sledz <sledz@dresearch.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-02-20tcp: Remove debug macro of TCP_CHECK_TIMERShan Wei1-9/+0
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>
2011-01-24net: change netdev->features to u32Michał Mirosław1-1/+1
Quoting Ben Hutchings: we presumably won't be defining features that can only be enabled on 64-bit architectures. Occurences found by `grep -r` on net/, drivers/net, include/ [ Move features and vlan_features next to each other in struct netdev, as per Eric Dumazet's suggestion -DaveM ] Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-12-08Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6David S. Miller1-1/+1
Conflicts: drivers/net/wireless/ath/ath9k/ar9003_eeprom.c net/llc/af_llc.c
2010-11-24tcp: Make TCP_MAXSEG minimum more correct.David S. Miller1-1/+1
Use TCP_MIN_MSS instead of constant 64. Reported-by: Min Zhang <mzhang@mvista.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-11-14Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6David S. Miller1-3/+3
2010-11-10tcp: Increase TCP_MAXSEG socket option minimum.David S. Miller1-1/+1
As noted by Steve Chen, since commit f5fff5dc8a7a3f395b0525c02ba92c95d42b7390 ("tcp: advertise MSS requested by user") we can end up with a situation where tcp_select_initial_window() does a divide by a zero (or even negative) mss value. The problem is that sometimes we effectively subtract TCPOLEN_TSTAMP_ALIGNED and/or TCPOLEN_MD5SIG_ALIGNED from the mss. Fix this by increasing the minimum from 8 to 64. Reported-by: Steve Chen <schen@mvista.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-11-10net: avoid limits overflowEric Dumazet1-2/+2
Robin Holt tried to boot a 16TB machine and found some limits were reached : sysctl_tcp_mem[2], sysctl_udp_mem[2] We can switch infrastructure to use long "instead" of "int", now atomic_long_t primitives are available for free. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Reported-by: Robin Holt <holt@sgi.com> Reviewed-by: Robin Holt <holt@sgi.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-11-09net/ipv4/tcp.c: Update WARN usesJoe Perches1-9/+7
Coalesce long formats. Align arguments. Remove KERN_<level>. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-10-04Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6David S. Miller1-1/+1
Conflicts: net/ipv4/Kconfig net/ipv4/tcp_timer.c
2010-09-27tcp: Fix >4GB writes on 64-bit.David S. Miller1-1/+1
Fixes kernel bugzilla #16603 tcp_sendmsg() truncates iov_len to an 'int' which a 4GB write to write zero bytes, for example. There is also the problem higher up of how verify_iovec() works. It wants to prevent the total length from looking like an error return value. However it does this using 'int', but syscalls return 'long' (and thus signed 64-bit on 64-bit machines). So it could trigger false-positives on 64-bit as written. So fix it to use 'long'. Reported-by: Olaf Bonorden <bono@onlinehome.de> Reported-by: Daniel Büse <dbuese@gmx.de> Reported-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-27Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6David S. Miller1-2/+5
Conflicts: drivers/net/qlcnic/qlcnic_init.c net/ipv4/ip_output.c
2010-09-20tcp: Fix race in tcp_pollTom Marshall1-2/+5
If a RST comes in immediately after checking sk->sk_err, tcp_poll will return POLLIN but not POLLOUT. Fix this by checking sk->sk_err at the end of tcp_poll. Additionally, ensure the correct order of operations on SMP machines with memory barriers. Signed-off-by: Tom Marshall <tdm.code@gmail.com> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-09Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6David S. Miller1-22/+10
Conflicts: net/mac80211/main.c
2010-08-30tcp: Add TCP_USER_TIMEOUT socket option.Jerry Chu1-1/+10
This patch provides a "user timeout" support as described in RFC793. The socket option is also needed for the the local half of RFC5482 "TCP User Timeout Option". TCP_USER_TIMEOUT is a TCP level socket option that takes an unsigned int, when > 0, to specify the maximum amount of time in ms that transmitted data may remain unacknowledged before TCP will forcefully close the corresponding connection and return ETIMEDOUT to the application. If 0 is given, TCP will continue to use the system default. Increasing the user timeouts allows a TCP connection to survive extended periods without end-to-end connectivity. Decreasing the user timeouts allows applications to "fail fast" if so desired. Otherwise it may take upto 20 minutes with the current system defaults in a normal WAN environment. The socket option can be made during any state of a TCP connection, but is only effective during the synchronized states of a connection (ESTABLISHED, FIN-WAIT-1, FIN-WAIT-2, CLOSE-WAIT, CLOSING, or LAST-ACK). Moreover, when used with the TCP keepalive (SO_KEEPALIVE) option, TCP_USER_TIMEOUT will overtake keepalive to determine when to close a connection due to keepalive failure. The option does not change in anyway when TCP retransmits a packet, nor when a keepalive probe will be sent. This option, like many others, will be inherited by an acceptor from its listener. Signed-off-by: H.K. Jerry Chu <hkchu@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-08-25tcp: select(writefds) don't hang up when a peer close connectionKOSAKI Motohiro1-1/+2
This issue come from ruby language community. Below test program hang up when only run on Linux. % uname -mrsv Linux 2.6.26-2-486 #1 Sat Dec 26 08:37:39 UTC 2009 i686 % ruby -rsocket -ve ' BasicSocket.do_not_reverse_lookup = true serv = TCPServer.open("127.0.0.1", 0) s1 = TCPSocket.open("127.0.0.1", serv.addr[1]) s2 = serv.accept s2.close s1.write("a") rescue p $! s1.write("a") rescue p $! Thread.new { s1.write("a") }.join' ruby 1.9.3dev (2010-07-06 trunk 28554) [i686-linux] #<Errno::EPIPE: Broken pipe> [Hang Here] FreeBSD, Solaris, Mac doesn't. because Ruby's write() method call select() internally. and tcp_poll has a bug. SUS defined 'ready for writing' of select() as following. | A descriptor shall be considered ready for writing when a call to an output | function with O_NONBLOCK clear would not block, whether or not the function | would transfer data successfully. That said, EPIPE situation is clearly one of 'ready for writing'. We don't have read-side issue because tcp_poll() already has read side shutdown care. | if (sk->sk_shutdown & RCV_SHUTDOWN) | mask |= POLLIN | POLLRDNORM | POLLRDHUP; So, Let's insert same logic in write side. - reference url http://blade.nagaokaut.ac.jp/cgi-bin/scat.rb/ruby/ruby-core/31065 http://blade.nagaokaut.ac.jp/cgi-bin/scat.rb/ruby/ruby-core/31068 Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-08-25tcp: fix three tcp sysctls tuningEric Dumazet1-17/+7
As discovered by Anton Blanchard, current code to autotune tcp_death_row.sysctl_max_tw_buckets, sysctl_tcp_max_orphans and sysctl_max_syn_backlog makes little sense. The bigger a page is, the less tcp_max_orphans is : 4096 on a 512GB machine in Anton's case. (tcp_hashinfo.bhash_size * sizeof(struct inet_bind_hashbucket)) is much bigger if spinlock debugging is on. Its wrong to select bigger limits in this case (where kernel structures are also bigger) bhash_size max is 65536, and we get this value even for small machines. A better ground is to use size of ehash table, this also makes code shorter and more obvious. Based on a patch from Anton, and another from David. Reported-and-tested-by: Anton Blanchard <anton@samba.org> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-08-25tcp: Combat per-cpu skew in orphan tests.David S. Miller1-4/+1
As reported by Anton Blanchard when we use percpu_counter_read_positive() to make our orphan socket limit checks, the check can be off by up to num_cpus_online() * batch (which is 32 by default) which on a 128 cpu machine can be as large as the default orphan limit itself. Fix this by doing the full expensive sum check if the optimized check triggers. Reported-by: Anton Blanchard <anton@samba.org> Signed-off-by: David S. Miller <davem@davemloft.net> Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
2010-08-02Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6David S. Miller1-2/+5
Conflicts: drivers/net/e1000e/hw.h net/bridge/br_device.c net/bridge/br_input.c
2010-08-02net: Add getsockopt support for TCP thin-streamsJosh Hunt1-0/+6
Initial TCP thin-stream commit did not add getsockopt support for the new socket options: TCP_THIN_LINEAR_TIMEOUTS and TCP_THIN_DUPACK. This adds support for them. Signed-off-by: Josh Hunt <johunt@akamai.com> Tested-by: Andreas Petlund <apetlund@simula.no> Acked-by: Andreas Petlund <apetlund@simula.no> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-07-30tcp: cookie transactions setsockopt memory leakDmitry Popov1-2/+5
There is a bug in do_tcp_setsockopt(net/ipv4/tcp.c), TCP_COOKIE_TRANSACTIONS case. In some cases (when tp->cookie_values == NULL) new tcp_cookie_values structure can be allocated (at cvp), but not bound to tp->cookie_values. So a memory leak occurs. Signed-off-by: Dmitry Popov <dp@highloadlab.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-07-20Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6David S. Miller1-0/+1
Conflicts: drivers/vhost/net.c net/bridge/br_device.c Fix merge conflict in drivers/vhost/net.c with guidance from Stephen Rothwell. Revert the effects of net-2.6 commit 573201f36fd9c7c6d5218cdcd9948cee700b277d since net-next-2.6 has fixes that make bridge netpoll work properly thus we don't need it disabled. Signed-off-by: David S. Miller <davem@davemloft.net>
2010-07-14rfs: call sock_rps_record_flow() in tcp_splice_read()Changli Gao1-0/+1
rfs: call sock_rps_record_flow() in tcp_splice_read() call sock_rps_record_flow() in tcp_splice_read(), so the applications using splice(2) or sendfile(2) can utilize RFS. Signed-off-by: Changli Gao <xiaosuo@gmail.com> ---- net/ipv4/tcp.c | 1 + 1 file changed, 1 insertion(+) Signed-off-by: David S. Miller <davem@davemloft.net>
2010-07-12inet, inet6: make tcp_sendmsg() and tcp_sendpage() through inet_sendmsg() and inet_sendpage()Changli Gao1-6/+5
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 Dumazet1-23/+12
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>
2010-06-28net: use this_cpu_ptr()Eric Dumazet1-1/+1
use this_cpu_ptr(p) instead of per_cpu_ptr(p, smp_processor_id()) Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-06-24tcp: do not send reset to already closed socketsKonstantin Khorenko1-0/+4
i've found that tcp_close() can be called for an already closed socket, but still sends reset in this case (tcp_send_active_reset()) which seems to be incorrect. Moreover, a packet with reset is sent with different source port as original port number has been already cleared on socket. Besides that incrementing stat counter for LINUX_MIB_TCPABORTONCLOSE also does not look correct in this case. Initially this issue was found on 2.6.18-x RHEL5 kernel, but the same seems to be true for the current mainstream kernel (checked on 2.6.35-rc3). Please, correct me if i missed something. How that happens: 1) the server receives a packet for socket in TCP_CLOSE_WAIT state that triggers a tcp_reset(): Call Trace: <IRQ> [<ffffffff8025b9b9>] tcp_reset+0x12f/0x1e8 [<ffffffff80046125>] tcp_rcv_state_process+0x1c0/0xa08 [<ffffffff8003eb22>] tcp_v4_do_rcv+0x310/0x37a [<ffffffff80028bea>] tcp_v4_rcv+0x74d/0xb43 [<ffffffff8024ef4c>] ip_local_deliver_finish+0x0/0x259 [<ffffffff80037131>] ip_local_deliver+0x200/0x2f4 [<ffffffff8003843c>] ip_rcv+0x64c/0x69f [<ffffffff80021d89>] netif_receive_skb+0x4c4/0x4fa [<ffffffff80032eca>] process_backlog+0x90/0xec [<ffffffff8000cc50>] net_rx_action+0xbb/0x1f1 [<ffffffff80012d3a>] __do_softirq+0xf5/0x1ce [<ffffffff8001147a>] handle_IRQ_event+0x56/0xb0 [<ffffffff8006334c>] call_softirq+0x1c/0x28 [<ffffffff80070476>] do_softirq+0x2c/0x85 [<ffffffff80070441>] do_IRQ+0x149/0x152 [<ffffffff80062665>] ret_from_intr+0x0/0xa <EOI> [<ffffffff80008a2e>] __handle_mm_fault+0x6cd/0x1303 [<ffffffff80008903>] __handle_mm_fault+0x5a2/0x1303 [<ffffffff80033a9d>] cache_free_debugcheck+0x21f/0x22e [<ffffffff8006a263>] do_page_fault+0x49a/0x7dc [<ffffffff80066487>] thread_return+0x89/0x174 [<ffffffff800c5aee>] audit_syscall_exit+0x341/0x35c [<ffffffff80062e39>] error_exit+0x0/0x84 tcp_rcv_state_process() ... // (sk_state == TCP_CLOSE_WAIT here) ... /* step 2: check RST bit */ if(th->rst) { tcp_reset(sk); goto discard; } ... --------------------------------- tcp_rcv_state_process tcp_reset tcp_done tcp_set_state(sk, TCP_CLOSE); inet_put_port __inet_put_port inet_sk(sk)->num = 0; sk->sk_shutdown = SHUTDOWN_MASK; 2) After that the process (socket owner) tries to write something to that socket and "inet_autobind" sets a _new_ (which differs from the original!) port number for the socket: Call Trace: [<ffffffff80255a12>] inet_bind_hash+0x33/0x5f [<ffffffff80257180>] inet_csk_get_port+0x216/0x268 [<ffffffff8026bcc9>] inet_autobind+0x22/0x8f [<ffffffff80049140>] inet_sendmsg+0x27/0x57 [<ffffffff8003a9d9>] do_sock_write+0xae/0xea [<ffffffff80226ac7>] sock_writev+0xdc/0xf6 [<ffffffff800680c7>] _spin_lock_irqsave+0x9/0xe [<ffffffff8001fb49>] __pollwait+0x0/0xdd [<ffffffff8008d533>] default_wake_function+0x0/0xe [<ffffffff800a4f10>] autoremove_wake_function+0x0/0x2e [<ffffffff800f0b49>] do_readv_writev+0x163/0x274 [<ffffffff80066538>] thread_return+0x13a/0x174 [<ffffffff800145d8>] tcp_poll+0x0/0x1c9 [<ffffffff800c56d3>] audit_syscall_entry+0x180/0x1b3 [<ffffffff800f0dd0>] sys_writev+0x49/0xe4 [<ffffffff800622dd>] tracesys+0xd5/0xe0 3) sendmsg fails at last with -EPIPE (=> 'write' returns -EPIPE in userspace): F: tcp_sendmsg1 -EPIPE: sk=ffff81000bda00d0, sport=49847, old_state=7, new_state=7, sk_err=0, sk_shutdown=3 Call Trace: [<ffffffff80027557>] tcp_sendmsg+0xcb/0xe87 [<ffffffff80033300>] release_sock+0x10/0xae [<ffffffff8016f20f>] vgacon_cursor+0x0/0x1a7 [<ffffffff8026bd32>] inet_autobind+0x8b/0x8f [<ffffffff8003a9d9>] do_sock_write+0xae/0xea [<ffffffff80226ac7>] sock_writev+0xdc/0xf6 [<ffffffff800680c7>] _spin_lock_irqsave+0x9/0xe [<ffffffff8001fb49>] __pollwait+0x0/0xdd [<ffffffff8008d533>] default_wake_function+0x0/0xe [<ffffffff800a4f10>] autoremove_wake_function+0x0/0x2e [<ffffffff800f0b49>] do_readv_writev+0x163/0x274 [<ffffffff80066538>] thread_return+0x13a/0x174 [<ffffffff800145d8>] tcp_poll+0x0/0x1c9 [<ffffffff800c56d3>] audit_syscall_entry+0x180/0x1b3 [<ffffffff800f0dd0>] sys_writev+0x49/0xe4 [<ffffffff800622dd>] tracesys+0xd5/0xe0 tcp_sendmsg() ... /* Wait for a connection to finish. */ if ((1 << sk->sk_state) & ~(TCPF_ESTABLISHED | TCPF_CLOSE_WAIT)) { int old_state = sk->sk_state; if ((err = sk_stream_wait_connect(sk, &timeo)) != 0) { if (f_d && (err == -EPIPE)) { printk("F: tcp_sendmsg1 -EPIPE: sk=%p, sport=%u, old_state=%d, new_state=%d, " "sk_err=%d, sk_shutdown=%d\n", sk, ntohs(inet_sk(sk)->sport), old_state, sk->sk_state, sk->sk_err, sk->sk_shutdown); dump_stack(); } goto out_err; } } ... 4) Then the process (socket owner) understands that it's time to close that socket and does that (and thus triggers sending reset packet): Call Trace: ... [<ffffffff80032077>] dev_queue_xmit+0x343/0x3d6 [<ffffffff80034698>] ip_output+0x351/0x384 [<ffffffff80251ae9>] dst_output+0x0/0xe [<ffffffff80036ec6>] ip_queue_xmit+0x567/0x5d2 [<ffffffff80095700>] vprintk+0x21/0x33 [<ffffffff800070f0>] check_poison_obj+0x2e/0x206 [<ffffffff80013587>] poison_obj+0x36/0x45 [<ffffffff8025dea6>] tcp_send_active_reset+0x15/0x14d [<ffffffff80023481>] dbg_redzone1+0x1c/0x25 [<ffffffff8025dea6>] tcp_send_active_reset+0x15/0x14d [<ffffffff8000ca94>] cache_alloc_debugcheck_after+0x189/0x1c8 [<ffffffff80023405>] tcp_transmit_skb+0x764/0x786 [<ffffffff8025df8a>] tcp_send_active_reset+0xf9/0x14d [<ffffffff80258ff1>] tcp_close+0x39a/0x960 [<ffffffff8026be12>] inet_release+0x69/0x80 [<ffffffff80059b31>] sock_release+0x4f/0xcf [<ffffffff80059d4c>] sock_close+0x2c/0x30 [<ffffffff800133c9>] __fput+0xac/0x197 [<ffffffff800252bc>] filp_close+0x59/0x61 [<ffffffff8001eff6>] sys_close+0x85/0xc7 [<ffffffff800622dd>] tracesys+0xd5/0xe0 So, in brief: * a received packet for socket in TCP_CLOSE_WAIT state triggers tcp_reset() which clears inet_sk(sk)->num and put socket into TCP_CLOSE state * an attempt to write to that socket forces inet_autobind() to get a new port (but the write itself fails with -EPIPE) * tcp_close() called for socket in TCP_CLOSE state sends an active reset via socket with newly allocated port This adds an additional check in tcp_close() for already closed sockets. We do not want to send anything to closed sockets. Signed-off-by: Konstantin Khorenko <khorenko@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-06-15tcp: unify tcp flag macrosChangli Gao1-4/+4
unify tcp flag macros: TCPHDR_FIN, TCPHDR_SYN, TCPHDR_RST, TCPHDR_PSH, TCPHDR_ACK, TCPHDR_URG, TCPHDR_ECE and TCPHDR_CWR. TCBCB_FLAG_* are replaced with the corresponding TCPHDR_*. Signed-off-by: Changli Gao <xiaosuo@gmail.com> ---- include/net/tcp.h | 24 ++++++------- net/ipv4/tcp.c | 8 ++-- net/ipv4/tcp_input.c | 2 - net/ipv4/tcp_output.c | 59 ++++++++++++++++----------------- net/netfilter/nf_conntrack_proto_tcp.c | 32 ++++++----------- net/netfilter/xt_TCPMSS.c | 4 -- 6 files changed, 58 insertions(+), 71 deletions(-) Signed-off-by: David S. Miller <davem@davemloft.net>
2010-05-31tcp: tcp_md5_hash_skb_data() frag_list handlingEric Dumazet1-0/+5
tcp_md5_hash_skb_data() should handle skb->frag_list, and eventually recurse. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-05-17net: Remove unnecessary semicolons after switch statementsJoe Perches1-1/+1
Also added an explicit break; to avoid a fallthrough in net/ipv4/tcp_input.c Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-05-16Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6David S. Miller1-10/+24
Conflicts: include/linux/if_link.h
2010-05-16tcp: fix MD5 (RFC2385) supportEric Dumazet1-10/+24
TCP MD5 support uses percpu data for temporary storage. It currently disables preemption so that same storage cannot be reclaimed by another thread on same cpu. We also have to make sure a softirq handler wont try to use also same context. Various bug reports demonstrated corruptions. Fix is to disable preemption and BH. Reported-by: Bhaskar Dutta <bhaskie@gmail.com> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-04-27TCP: avoid to send keepalive probes if receiving dataFlavio Leitner1-1/+1
RFC 1122 says the following: ... Keep-alive packets MUST only be sent when no data or acknowledgement packets have been received for the connection within an interval. ... The acknowledgement packet is reseting the keepalive timer but the data packet isn't. This patch fixes it by checking the timestamp of the last received data packet too when the keepalive timer expires. Signed-off-by: Flavio Leitner <fleitner@redhat.com> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Acked-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-04-20net: Fix various endianness glitchesEric Dumazet1-7/+8
Sparse can help us find endianness bugs, but we need to make some cleanups to be able to more easily spot real bugs. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>