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2005-08-29[INET]: Generalise the tcp_listen_ lock routinesArnaldo Carvalho de Melo
Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29[INET]: Move tcp_port_rover to inet_hashinfoArnaldo Carvalho de Melo
Also expose all of the tcp_hashinfo members, i.e. killing those tcp_ehash, etc macros, this will more clearly expose already generic functions and some that need just a bit of work to become generic, as we'll see in the upcoming changesets. Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29[INET]: Generalise tcp_bind_hash & tcp_inherit_portArnaldo Carvalho de Melo
This required moving tcp_bucket_cachep to inet_hashinfo. Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29[NETFILTER]: fix list traversal order in ctnetlinkPablo Neira Ayuso
Currently conntracks are inserted after the head. That means that conntracks are sorted from the biggest to the smallest id. This happens because we use list_prepend (list_add) instead list_add_tail. This can result in problems during the list iteration. list_for_each(i, &ip_conntrack_hash[cb->args[0]]) { h = (struct ip_conntrack_tuple_hash *) i; if (DIRECTION(h) != IP_CT_DIR_ORIGINAL) continue; ct = tuplehash_to_ctrack(h); if (ct->id <= *id) continue; In that case just the first conntrack in the bucket will be dumped. To fix this, we iterate the list from the tail to the head via list_for_each_prev. Same thing for the list of expectations. Signed-off-by: Pablo Neira Ayuso <pablo@eurodev.net> Signed-off-by: Harald Welte <laforge@netfilter.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29[NETFILTER]: Fix typo in ctnl_exp_cb array (no bug, just memory waste)Pablo Neira Ayuso
This fixes the size of the ctnl_exp_cb array that is IPCTNL_MSG_EXP_MAX instead of IPCTNL_MSG_MAX. Simple typo. Signed-off-by: Pablo Neira Ayuso <pablo@eurodev.net> Signed-off-by: Harald Welte <laforge@netfilter.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29[NETFILTER]: fix conntrack refcount leak in unlink_expect()Pablo Neira Ayuso
In unlink_expect(), the expectation is removed from the list so the refcount must be dropped as well. Signed-off-by: Pablo Neira Ayuso <pablo@eurodev.net> Signed-off-by: Harald Welte <laforge@netfilter.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29[NETFILTER]: ctnetlink: make sure event order is correctPablo Neira Ayuso
The following sequence is displayed during events dumping of an ICMP connection: [NEW] [DESTROY] [UPDATE] This happens because the event IPCT_DESTROY is delivered in death_by_timeout(), that is called from the icmp protocol helper (ct->timeout.function) once we see the reply. To fix this, we move this event to destroy_conntrack(). Signed-off-by: Pablo Neira Ayuso <pablo@eurodev.net> Signed-off-by: Harald Welte <laforge@netfilter.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29[NETFILTER]: don't use nested attributes for conntrack_expectHarald Welte
We used to use nested nfattr structures for ip_conntrack_expect. This is bogus, since ip_conntrack and ip_conntrack_expect are communicated in different netlink message types. both should be encoded at the top level attributes, no extra nesting required. This patch addresses the issue. Signed-off-by: Harald Welte <laforge@netfilter.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29[NETFILTER]: attribute count is an attribute of message type, not subsytemHarald Welte
Prior to this patch, every nfnetlink subsystem had to specify it's attribute count. However, in reality the attribute count depends on the message type within the subsystem, not the subsystem itself. This patch moves 'attr_count' from 'struct nfnetlink_subsys' into nfnl_callback to fix this. Signed-off-by: Harald Welte <laforge@netfilter.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29[NETFILTER]: fix ctnetlink 'create_expect' parsingHarald Welte
There was a stupid copy+paste mistake where we parse the MASK nfattr into the "tuple" variable instead of the "mask" variable. This patch fixes it. Thanks to Pablo Neira. Signed-off-by: Harald Welte <laforge@netfilter.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29[NETFILTER]: conntrack_netlink: Fix locking during conntrack_createPablo Neira
The current codepath allowed for ip_conntrack_lock to be unlock'ed twice. Signed-off-by: Pablo Neira <pablo@eurodev.net> Signed-off-by: Harald Welte <laforge@netfilter.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29[NETFILTER]: remove bogus memset() calls from ip_conntrack_netlink.cPablo Neira
nfattr_parse_nested() calls nfattr_parse() which in turn does a memset on the 'tb' array. All callers therefore don't need to memset before calling it. Signed-off-by: Pablo Neira <pablo@eurodev.net> Signed-off-by: Harald Welte <laforge@netfilter.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29[NETFILTER]: Fix multiple problems with the conntrack event cachePatrick McHardy
refcnt underflow: the reference count is decremented when a conntrack entry is removed from the hash but it is not incremented when entering new entries. missing protection of process context against softirq context: all cache operations need to locally disable softirqs to avoid races. Additionally the event cache can't be initialized when a packet enteres the conntrack code but needs to be initialized whenever we cache an event and the stored conntrack entry doesn't match the current one. incorrect flushing of the event cache in ip_ct_iterate_cleanup: without real locking we can't flush the cache for different CPUs without incurring races. The cache for different CPUs can only be flushed when no packets are going through the code. ip_ct_iterate_cleanup doesn't need to drop all references, so flushing is moved to the cleanup path. Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29[INET]: Move bind_hash from tcp_sk to inet_skArnaldo Carvalho de Melo
This should really be in a inet_connection_sock, but I'm leaving it for a later optimization, when some more fields common to INET transport protocols now in tcp_sk or inet_sk will be chunked out into inet_connection_sock, for now its better to concentrate on getting the changes in the core merged to leave the DCCP tree with only DCCP specific code. Next changesets will take advantage of this move to generalise things like tcp_bind_hash, tcp_put_port, tcp_inherit_port, making the later receive a inet_hashinfo parameter, and even __tcp_tw_hashdance, etc in the future, when tcp_tw_bucket gets transformed into the struct timewait_sock hierarchy. tcp_destroy_sock also is eligible as soon as tcp_orphan_count gets moved to sk_prot. A cascade of incremental changes will ultimately make the tcp_lookup functions be fully generic. Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29[INET]: Move the TCP hashtable functions/structs to inet_hashtables.[ch]Arnaldo Carvalho de Melo
Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29[INET]: Just rename the TCP hashtable functions/structs to inet_Arnaldo Carvalho de Melo
This is to break down the complexity of the series of patches, making it very clear that this one just does: 1. renames tcp_ prefixed hashtable functions and data structures that were already mostly generic to inet_ to share it with DCCP and other INET transport protocols. 2. Removes not used functions (__tb_head & tb_head) 3. Removes some leftover prototypes in the headers (tcp_bucket_unlock & tcp_v4_build_header) Next changesets will move tcp_sk(sk)->bind_hash to inet_sock so that we can make functions such as tcp_inherit_port, __tcp_inherit_port, tcp_v4_get_port, __tcp_put_port, generic and get others like tcp_destroy_sock closer to generic (tcp_orphan_count will go to sk->sk_prot to allow this). Eventually most of these functions will be used passing the transport protocol inet_hashinfo structure. Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29[INET]: Move the TCP ehash functions to include/net/inet_hashtables.hArnaldo Carvalho de Melo
To be shared with DCCP (and others), this is the start of a series of patches that will expose the already generic TCP hash table routines. The few changes noticed when calling gcc -S before/after on a pentium4 were of this type: movl 40(%esp), %edx cmpl %esi, 472(%edx) je .L168 - pushl $291 + pushl $272 pushl $.LC0 pushl $.LC1 pushl $.LC2 [acme@toy net-2.6.14]$ size net/ipv4/tcp_ipv4.before.o net/ipv4/tcp_ipv4.after.o text data bss dec hex filename 17804 516 140 18460 481c net/ipv4/tcp_ipv4.before.o 17804 516 140 18460 481c net/ipv4/tcp_ipv4.after.o Holler if some weird architecture has issues with things like this 8) Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29[NETFILTER]: Extend netfilter logging APIHarald Welte
This patch is in preparation to nfnetlink_log: - loggers now have to register struct nf_logger instead of nf_logfn - nf_log_unregister() replaced by nf_log_unregister_pf() and nf_log_unregister_logger() - add comment to ip[6]t_LOG.h to assure nobody redefines flags - add /proc/net/netfilter/nf_log to tell user which logger is currently registered for which address family - if user has configured logging, but no logging backend (logger) is available, always spit a message to syslog, not just the first time. - split ip[6]t_LOG.c into two parts: Backend: Always try to register as logger for the respective address family Frontend: Always log via nf_log_packet() API - modify all users of nf_log_packet() to accomodate additional argument Signed-off-by: Harald Welte <laforge@netfilter.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29[INET]: Introduce inet_sk_rebuild_headerArnaldo Carvalho de Melo
From tcp_v4_rebuild_header, that already was pretty generic, I only needed to use sk->sk_protocol instead of the hardcoded IPPROTO_TCP and establish the requirement that INET transport layer protocols that want to use this function map TCP_SYN_SENT to its equivalent state. Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29[SOCK]: Introduce sk_setup_capsArnaldo Carvalho de Melo
From tcp_v4_setup_caps, that always is preceded by a call to __sk_dst_set, so coalesce this sequence into sk_setup_caps, removing one call to a TCP function in the IP layer. Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29[SOCK]: Rename __tcp_v4_rehash to __sk_prot_rehashArnaldo Carvalho de Melo
This operation was already generic and DCCP will use it. Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29[NET]: Cleanup INET_REFCNT_DEBUG codeArnaldo Carvalho de Melo
Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29[IPV4/6]: Check if packet was actually delivered to a raw socket to decide ↵Patrick McHardy
whether to send an ICMP unreachable Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29[NETFILTER]: Add "nfnetlink_queue" netfilter queue handler over nfnetlinkHarald Welte
- Add new nfnetlink_queue module - Add new ipt_NFQUEUE and ip6t_NFQUEUE modules to access queue numbers 1-65535 - Mark ip_queue and ip6_queue Kconfig options as OBSOLETE - Update feature-removal-schedule to remove ip[6]_queue in December Signed-off-by: Harald Welte <laforge@netfilter.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29[NETFILTER]: Core changes required by upcoming nfnetlink_queue codeHarald Welte
- split netfiler verdict in 16bit verdict and 16bit queue number - add 'queuenum' argument to nf_queue_outfn_t and its users ip[6]_queue - move NFNL_SUBSYS_ definitions from enum to #define - introduce autoloading for nfnetlink subsystem modules - add MODULE_ALIAS_NFNL_SUBSYS macro - add nf_unregister_queue_handlers() to register all handlers for a given nf_queue_outfn_t - add more verbose DEBUGP macro definition to nfnetlink.c - make nfnetlink_subsys_register fail if subsys already exists - add some more comments and debug statements to nfnetlink.c Signed-off-by: Harald Welte <laforge@netfilter.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29[NETFILTER]: Move reroute-after-queue code up to the nf_queue layer.Harald Welte
The rerouting functionality is required by the core, therefore it has to be implemented by the core and not in individual queue handlers. Signed-off-by: Harald Welte <laforge@netfilter.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29[NETLINK]: Add properly module refcounting for kernel netlink sockets.Harald Welte
- Remove bogus code for compiling netlink as module - Add module refcounting support for modules implementing a netlink protocol - Add support for autoloading modules that implement a netlink protocol as soon as someone opens a socket for that protocol Signed-off-by: Harald Welte <laforge@netfilter.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29[NETFILTER]: Move ipv4 specific code from net/core/netfilter.c to ↵Harald Welte
net/ipv4/netfilter.c Netfilter cleanup - Move ipv4 code from net/core/netfilter.c to net/ipv4/netfilter.c - Move ipv6 netfilter code from net/ipv6/ip6_output.c to net/ipv6/netfilter.c Signed-off-by: Harald Welte <laforge@netfilter.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29[NETFILTER]: Rename skb_ip_make_writable() to skb_make_writable()Harald Welte
There is nothing IPv4-specific in it. In fact, it was already used by IPv6, too... Upcoming nfnetlink_queue code will use it for any kind of packet. Signed-off-by: Harald Welte <laforge@netfilter.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29[NETFILTER]: C99 initizalizers for NAT protocolsPatrick McHardy
Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29[IPV4]: possible cleanupsAdrian Bunk
This patch contains the following possible cleanups: - make needlessly global code static - #if 0 the following unused global function: - xfrm4_state.c: xfrm4_state_fini - remove the following unneeded EXPORT_SYMBOL's: - ip_output.c: ip_finish_output - ip_output.c: sysctl_ip_default_ttl - fib_frontend.c: ip_dev_find - inetpeer.c: inet_peer_idlock - ip_options.c: ip_options_compile - ip_options.c: ip_options_undo - net/core/request_sock.c: sysctl_max_syn_backlog Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29[NET]: Kill skb->real_devDavid S. Miller
Bonding just wants the device before the skb_bond() decapsulation occurs, so simply pass that original device into packet_type->func() as an argument. It remains to be seen whether we can use this same exact thing to get rid of skb->input_dev as well. Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29[REQSK]: Move the syn_table destroy from tcp_listen_stop to reqsk_queue_destroyArnaldo Carvalho de Melo
Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29[NETFILTER]: Add ctnetlink subsystemHarald Welte
Add ctnetlink subsystem for userspace-access to ip_conntrack table. This allows reading and updating of existing entries, as well as creating new ones (and new expect's) via nfnetlink. Please note the 'strange' byte order: nfattr (tag+length) are in host byte order, while the payload is always guaranteed to be in network byte order. This allows a simple userspace process to encapsulate netlink messages into arch-independent udp packets by just processing/swapping the headers and not knowing anything about the actual payload. Signed-off-by: Harald Welte <laforge@netfilter.org> Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29[NETFILTER]: connection tracking event notifiersHarald Welte
This adds a notifier chain based event mechanism for ip_conntrack state changes. As opposed to the previous implementations in patch-o-matic, we do no longer need a field in the skb to achieve this. Thanks to the valuable input from Patrick McHardy and Rusty on the idea of a per_cpu implementation. Signed-off-by: Harald Welte <laforge@netfilter.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29[NET]: Kill skb->listDavid S. Miller
Remove the "list" member of struct sk_buff, as it is entirely redundant. All SKB list removal callers know which list the SKB is on, so storing this in sk_buff does nothing other than taking up some space. Two tricky bits were SCTP, which I took care of, and two ATM drivers which Francois Romieu <romieu@fr.zoreil.com> fixed up. Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Francois Romieu <romieu@fr.zoreil.com>
2005-08-29[NETFILTER]: reduce netfilter sk_buff enlargementHarald Welte
As discussed at netconf'05, we're trying to save every bit in sk_buff. The patch below makes sk_buff 8 bytes smaller. I did some basic testing on my notebook and it seems to work. The only real in-tree user of nfcache was IPVS, who only needs a single bit. Unfortunately I couldn't find some other free bit in sk_buff to stuff that bit into, so I introduced a separate field for them. Maybe the IPVS guys can resolve that to further save space. Initially I wanted to shrink pkt_type to three bits (PACKET_HOST and alike are only 6 values defined), but unfortunately the bluetooth code overloads pkt_type :( The conntrack-event-api (out-of-tree) uses nfcache, but Rusty just came up with a way how to do it without any skb fields, so it's safe to remove it. - remove all never-implemented 'nfcache' code - don't have ipvs code abuse 'nfcache' field. currently get's their own compile-conditional skb->ipvs_property field. IPVS maintainers can decide to move this bit elswhere, but nfcache needs to die. - remove skb->nfcache field to save 4 bytes - move skb->nfctinfo into three unused bits to save further 4 bytes Signed-off-by: Harald Welte <laforge@netfilter.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29[NETFILTER]: convert nfmark and conntrack mark to 32bitHarald Welte
As discussed at netconf'05, we convert nfmark and conntrack-mark to be 32bits even on 64bit architectures. Signed-off-by: Harald Welte <laforge@netfilter.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-23[FIB_TRIE]: Don't ignore negative results from fib_semantic_matchPatrick McHardy
When a semantic match occurs either success, not found or an error (for matching unreachable routes/blackholes) is returned. fib_trie ignores the errors and looks for a different matching route. Treat results other than "no match" as success and end lookup. Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-23[TCP]: Document non-trivial locking path in tcp_v{4,6}_get_port().David S. Miller
This trips up a lot of folks reading this code. Put an unlikely() around the port-exhaustion test for good measure. Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-23[TCP]: Unconditionally clear TCP_NAGLE_PUSH in skb_entail().David S. Miller
Intention of this bit is to force pushing of the existing send queue when TCP_CORK or TCP_NODELAY state changes via setsockopt(). But it's easy to create a situation where the bit never clears. For example, if the send queue starts empty: 1) set TCP_NODELAY 2) clear TCP_NODELAY 3) set TCP_CORK 4) do small write() The current code will leave TCP_NAGLE_PUSH set after that sequence. Unconditionally clearing the bit when new data is added via skb_entail() solves the problem. Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-23[NETFILTER]: Fix HW checksum handling in ip_queue/ip6_queuePatrick McHardy
The checksum needs to be filled in on output, after mangling a packet ip_summed needs to be reset. Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-23[IPV4]: Fix negative timer loop with lots of ipv4 peers.Dave Johnson
From: Dave Johnson <djohnson+linux-kernel@sw.starentnetworks.com> Found this bug while doing some scaling testing that created 500K inet peers. peer_check_expire() in net/ipv4/inetpeer.c isn't using inet_peer_gc_mintime correctly and will end up creating an expire timer with less than the minimum duration, and even zero/negative if enough active peers are present. If >65K peers, the timer will be less than inet_peer_gc_mintime, and with >70K peers, the timer duration will reach zero and go negative. The timer handler will continue to schedule another zero/negative timer in a loop until peers can be aged. This can continue for at least a few minutes or even longer if the peers remain active due to arriving packets while the loop is occurring. Bug is present in both 2.4 and 2.6. Same patch will apply to both just fine. Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-23[TCP]: Do TSO deferral even if tail SKB can go out now.Dmitry Yusupov
If the tail SKB fits into the window, it is still benefitical to defer until the goal percentage of the window is available. This give the application time to feed more data into the send queue and thus results in larger TSO frames going out. Patch from Dmitry Yusupov <dima@neterion.com>. Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-20[NETFILTER]: Fix HW checksum handling in TCPMSS targetPatrick McHardy
Most importantly, remove bogus BUG() in receive path. Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-20[NETFILTER]: Fix HW checksum handling in ECN targetPatrick McHardy
Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-20[NETFILTER]: Fix ECN target TCP markingPatrick McHardy
An incorrect check made it bail out before doing anything. Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-18[IPCOMP]: Fix false smp_processor_id warningHerbert Xu
This patch fixes a false-positive from debug_smp_processor_id(). The processor ID is only used to look up crypto_tfm objects. Any processor ID is acceptable here as long as it is one that is iterated on by for_each_cpu(). Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-18[IPV4]: Fix DST leak in icmp_push_reply()Patrick McHardy
Based upon a bug report and initial patch by Ollie Wild. Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-16[TCP]: Fix bug #5070: kernel BUG at net/ipv4/tcp_output.c:864Herbert Xu
1) We send out a normal sized packet with TSO on to start off. 2) ICMP is received indicating a smaller MTU. 3) We send the current sk_send_head which needs to be fragmented since it was created before the ICMP event. The first fragment is then sent out. At this point the remaining fragment is allocated by tcp_fragment. However, its size is padded to fit the L1 cache-line size therefore creating tail-room up to 124 bytes long. This fragment will also be sitting at sk_send_head. 4) tcp_sendmsg is called again and it stores data in the tail-room of of the fragment. 5) tcp_push_one is called by tcp_sendmsg which then calls tso_fragment since the packet as a whole exceeds the MTU. At this point we have a packet that has data in the head area being fed to tso_fragment which bombs out. My take on this is that we shouldn't ever call tcp_fragment on a TSO socket for a packet that is yet to be transmitted since this creates a packet on sk_send_head that cannot be extended. So here is a patch to change it so that tso_fragment is always used in this case. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>