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* netfilter: nf_tables: restore context for expression destructorsPatrick McHardy2014-03-086-23/+27
| | | | | | | | | | | | In order to fix set destruction notifications and get rid of unnecessary members in private data structures, pass the context to expressions' destructor functions again. In order to do so, replace various members in the nft_rule_trans structure by the full context. Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* netfilter: nf_tables: clean up nf_tables_trans_add() argument orderPatrick McHardy2014-03-081-4/+4
| | | | | | | | The context argument logically comes first, and this is what every other function dealing with contexts does. Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* netfilter: nft_hash: bug fixes and resizingPatrick McHardy2014-03-071-46/+214
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The hash set type is very broken and was never meant to be merged in this state. Missing RCU synchronization on element removal, leaking chain refcounts when used as a verdict map, races during lookups, a fixed table size are probably just some of the problems. Luckily it is currently never chosen by the kernel when the rbtree type is also available. Rewrite it to be usable. The new implementation supports automatic hash table resizing using RCU, based on Paul McKenney's and Josh Triplett's algorithm "Optimized Resizing For RCU-Protected Hash Tables" described in [1]. Resizing doesn't require a second list head in the elements, it works by chosing a hash function that remaps elements to a predictable set of buckets, only resizing by integral factors and - during expansion: linking new buckets to the old bucket that contains elements for any of the new buckets, thereby creating imprecise chains, then incrementally seperating the elements until the new buckets only contain elements that hash directly to them. - during shrinking: linking the hash chains of all old buckets that hash to the same new bucket to form a single chain. Expansion requires at most the number of elements in the longest hash chain grace periods, shrinking requires a single grace period. Due to the requirement of having hash chains/elements linked to multiple buckets during resizing, homemade single linked lists are used instead of the existing list helpers, that don't support this in a clean fashion. As a side effect, the amount of memory required per element is reduced by one pointer. Expansion is triggered when the load factors exceeds 75%, shrinking when the load factor goes below 30%. Both operations are allowed to fail and will be retried on the next insertion or removal if their respective conditions still hold. [1] http://dl.acm.org/citation.cfm?id=2002181.2002192 Reviewed-by: Josh Triplett <josh@joshtriplett.org> Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* netfilter: conntrack: remove central spinlock nf_conntrack_lockJesper Dangaard Brouer2014-03-073-66/+180
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | nf_conntrack_lock is a monolithic lock and suffers from huge contention on current generation servers (8 or more core/threads). Perf locking congestion is clear on base kernel: - 72.56% ksoftirqd/6 [kernel.kallsyms] [k] _raw_spin_lock_bh - _raw_spin_lock_bh + 25.33% init_conntrack + 24.86% nf_ct_delete_from_lists + 24.62% __nf_conntrack_confirm + 24.38% destroy_conntrack + 0.70% tcp_packet + 2.21% ksoftirqd/6 [kernel.kallsyms] [k] fib_table_lookup + 1.15% ksoftirqd/6 [kernel.kallsyms] [k] __slab_free + 0.77% ksoftirqd/6 [kernel.kallsyms] [k] inet_getpeer + 0.70% ksoftirqd/6 [nf_conntrack] [k] nf_ct_delete + 0.55% ksoftirqd/6 [ip_tables] [k] ipt_do_table This patch change conntrack locking and provides a huge performance improvement. SYN-flood attack tested on a 24-core E5-2695v2(ES) with 10Gbit/s ixgbe (with tool trafgen): Base kernel: 810.405 new conntrack/sec After patch: 2.233.876 new conntrack/sec Notice other floods attack (SYN+ACK or ACK) can easily be deflected using: # iptables -A INPUT -m state --state INVALID -j DROP # sysctl -w net/netfilter/nf_conntrack_tcp_loose=0 Use an array of hashed spinlocks to protect insertions/deletions of conntracks into the hash table. 1024 spinlocks seem to give good results, at minimal cost (4KB memory). Due to lockdep max depth, 1024 becomes 8 if CONFIG_LOCKDEP=y The hash resize is a bit tricky, because we need to take all locks in the array. A seqcount_t is used to synchronize the hash table users with the resizing process. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net> Reviewed-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* netfilter: conntrack: seperate expect locking from nf_conntrack_lockJesper Dangaard Brouer2014-03-076-69/+77
| | | | | | | | | | | Netfilter expectations are protected with the same lock as conntrack entries (nf_conntrack_lock). This patch split out expectations locking to use it's own lock (nf_conntrack_expect_lock). Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net> Reviewed-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* netfilter: avoid race with exp->master ctJesper Dangaard Brouer2014-03-072-1/+15
| | | | | | | | | | | | | | | | | | | | Preparation for disconnecting the nf_conntrack_lock from the expectations code. Once the nf_conntrack_lock is lifted, a race condition is exposed. The expectations master conntrack exp->master, can race with delete operations, as the refcnt increment happens too late in init_conntrack(). Race is against other CPUs invoking ->destroy() (destroy_conntrack()), or nf_ct_delete() (via timeout or early_drop()). Avoid this race in nf_ct_find_expectation() by using atomic_inc_not_zero(), and checking if nf_ct_is_dying() (path via nf_ct_delete()). Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* netfilter: conntrack: spinlock per cpu to protect special lists.Jesper Dangaard Brouer2014-03-073-75/+158
| | | | | | | | | | | | | One spinlock per cpu to protect dying/unconfirmed/template special lists. (These lists are now per cpu, a bit like the untracked ct) Add a @cpu field to nf_conn, to make sure we hold the appropriate spinlock at removal time. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net> Reviewed-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* netfilter: trivial code cleanup and doc changesJesper Dangaard Brouer2014-03-072-11/+11
| | | | | | | | | | | | Changes while reading through the netfilter code. Added hint about how conntrack nf_conn refcnt is accessed. And renamed repl_hash to reply_hash for readability Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net> Reviewed-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* Merge git://git.kernel.org/pub/scm/linux/kernel/git/horms/ipvs-nextPablo Neira Ayuso2014-03-072-8/+7
|\ | | | | | | | | | | | | | | | | | | | | | | Via Simon Horman: ==================== * Whitespace cleanup spotted by checkpatch.pl from Tingwei Liu. * Section conflict cleanup, basically removal of one wrong __read_mostly, from Andi Kleen. ==================== Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
| * ipvs: Reduce checkpatch noise in ip_vs_lblc.cTingwei Liu2014-03-071-7/+6
| | | | | | | | | | | | | | | | | | Add whitespace after operator and put open brace { on the previous line Cc: Tingwei Liu <liutingwei@hisense.com> Cc: lvs-devel@vger.kernel.org Signed-off-by: Tingwei Liu <tingw.liu@gmail.com> Signed-off-by: Simon Horman <horms@verge.net.au>
| * sections, ipvs: Remove useless __read_mostly for ipvs genl_opsAndi Kleen2014-03-071-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | const __read_mostly does not make any sense, because const data is already read-only. Remove the __read_mostly for the ipvs genl_ops. This avoids a LTO section conflict compile problem. Cc: Wensong Zhang <wensong@linux-vs.org> Cc: Simon Horman <horms@verge.net.au> Cc: Patrick McHardy <kaber@trash.net> Cc: lvs-devel@vger.kernel.org Signed-off-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: Simon Horman <horms@verge.net.au>
* | netfilter: ipset: add forceadd kernel support for hash set typesJosh Hunt2014-03-0612-10/+32
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Adds a new property for hash set types, where if a set is created with the 'forceadd' option and the set becomes full the next addition to the set may succeed and evict a random entry from the set. To keep overhead low eviction is done very simply. It checks to see which bucket the new entry would be added. If the bucket's pos value is non-zero (meaning there's at least one entry in the bucket) it replaces the first entry in the bucket. If pos is zero, then it continues down the normal add process. This property is useful if you have a set for 'ban' lists where it may not matter if you release some entries from the set early. Signed-off-by: Josh Hunt <johunt@akamai.com> Signed-off-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
* | netfilter: ipset: move registration message to init from net_initIlia Mirkin2014-03-061-1/+1
| | | | | | | | | | | | | | | | | | Commit 1785e8f473 ("netfiler: ipset: Add net namespace for ipset") moved the initialization print into net_init, which can get called a lot due to namespaces. Move it back into init, reduce to pr_info. Signed-off-by: Ilia Mirkin <imirkin@alum.mit.edu> Signed-off-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
* | netfilter: ipset: add markmask for hash:ip,mark data typeVytas Dauksa2014-03-062-0/+40
| | | | | | | | | | | | | | | | | | Introduce packet mark mask for hash:ip,mark data type. This allows to set mark bit filter for the ip set. Change-Id: Id8dd9ca7e64477c4f7b022a1d9c1a5b187f1c96e Signed-off-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
* | netfilter: ipset: add hash:ip,mark data type to ipsetVytas Dauksa2014-03-063-0/+322
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Introduce packet mark support with new ip,mark hash set. This includes userspace and kernelspace code, hash:ip,mark set tests and man page updates. The intended use of ip,mark set is similar to the ip:port type, but for protocols which don't use a predictable port number. Instead of port number it matches a firewall mark determined by a layer 7 filtering program like opendpi. As well as allowing or blocking traffic it will also be used for accounting packets and bytes sent for each protocol. Signed-off-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
* | netfilter: ipset: Add hash: fix coccinelle warningsFengguang Wu2014-03-061-4/+4
| | | | | | | | | | | | | | | | | | | | | | | | net/netfilter/ipset/ip_set_hash_netnet.c:115:8-9: WARNING: return of 0/1 in function 'hash_netnet4_data_list' with return type bool /c/kernel-tests/src/cocci/net/netfilter/ipset/ip_set_hash_netnet.c:338:8-9: WARNING: return of 0/1 in function 'hash_netnet6_data_list' with return type bool Return statements in functions returning bool should use true/false instead of 1/0. Generated by: coccinelle/misc/boolreturn.cocci Signed-off-by: Fengguang Wu <fengguang.wu@intel.com> Signed-off-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
* | netfilter: ipset: Follow manual page behavior for SET target on list:setSergey Popovich2014-03-061-2/+2
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | ipset(8) for list:set says: The match will try to find a matching entry in the sets and the target will try to add an entry to the first set to which it can be added. However real behavior is bit differ from described. Consider example: # ipset create test-1-v4 hash:ip family inet # ipset create test-1-v6 hash:ip family inet6 # ipset create test-1 list:set # ipset add test-1 test-1-v4 # ipset add test-1 test-1-v6 # iptables -A INPUT -p tcp --destination-port 25 -j SET --add-set test-1 src # ip6tables -A INPUT -p tcp --destination-port 25 -j SET --add-set test-1 src And then when iptables/ip6tables rule matches packet IPSET target tries to add src from packet to the list:set test-1 where first entry is test-1-v4 and the second one is test-1-v6. For IPv4, as it first entry in test-1 src added to test-1-v4 correctly, but for IPv6 src not added! Placing test-1-v6 to the first element of list:set makes behavior correct for IPv6, but brokes for IPv4. This is due to result, returned from ip_set_add() and ip_set_del() from net/netfilter/ipset/ip_set_core.c when set in list:set equires more parameters than given or address families do not match (which is this case). It seems wrong returning 0 from ip_set_add() and ip_set_del() in this case, as 0 should be returned only when an element successfuly added/deleted to/from the set, contrary to ip_set_test() which returns 0 when no entry exists and >0 when entry found in set. Signed-off-by: Sergey Popovich <popovich_sergei@mail.ru> Signed-off-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
* netfilter: nf_tables: add optional user data area to rulesPablo Neira Ayuso2014-02-271-2/+15
| | | | | | | | | | | | | | | This allows us to store user comment strings, but it could be also used to store any kind of information that the user application needs to link to the rule. Scratch 8 bits for the new ulen field that indicates the length the user data area. 4 bits from the handle (so it's 42 bits long, according to Patrick, it would last 139 years with 1000 new rules per second) and 4 bits from dlen (so the expression data area is 4K, which seems sufficient by now even considering the compatibility layer). Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Acked-by: Patrick McHardy <kaber@trash.net>
* netfilter: nfnetlink_log: remove unused codeFlorian Westphal2014-02-251-8/+0
| | | | | Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* netfilter: nf_tables: accept QUEUE/DROP verdict parametersPatrick McHardy2014-02-251-5/+10
| | | | | | | | Allow userspace to specify the queue number or the errno code for QUEUE and DROP verdicts. Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* netfilter: nf_tables: add nft_dereference() macroPatrick McHardy2014-02-251-2/+1
| | | | | Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* netfilter: nfnetlink: add rcu_dereference_protected() helpersPatrick McHardy2014-02-251-0/+8
| | | | | | | | Add a lockdep_nfnl_is_held() function and a nfnl_dereference() macro for RCU dereferences protected by a NFNL subsystem mutex. Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* netfilter: ip_set: rename nfnl_dereference()/nfnl_set()Patrick McHardy2014-02-251-23/+23
| | | | | | | | | The next patch will introduce a nfnl_dereference() macro that actually checks that the appropriate mutex is held and therefore needs a subsystem argument. Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* netfilter: nft_ct: labels get supportFlorian Westphal2014-02-192-3/+26
| | | | | | | | | | | | | | | | | This also adds NF_CT_LABELS_MAX_SIZE so it can be re-used as BUILD_BUG_ON in nft_ct. At this time, nft doesn't yet support writing to the label area; when this changes the label->words handling needs to be moved out of xt_connlabel.c into nf_conntrack_labels.c. Also removes a useless run-time check: words cannot grow beyond 4 (32 bit) or 2 (64bit) since xt_connlabel enforces a maximum of 128 labels. Signed-off-by: Florian Westphal <fw@strlen.de> Acked-by: Patrick McHardy <kaber@trash.net> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* netfilter: xt_ipcomp: Use ntohs to ease sparse warningPablo Neira Ayuso2014-02-191-1/+1
| | | | | | | | | | | | | | | | 0-DAY kernel build testing backend reported: sparse warnings: (new ones prefixed by >>) >> >> net/netfilter/xt_ipcomp.c:63:26: sparse: restricted __be16 degrades to integer >> >> net/netfilter/xt_ipcomp.c:63:26: sparse: cast to restricted __be32 Fix this by using ntohs without shifting. Tested with: make C=1 CF=-D__CHECK_ENDIAN__ Signed-off-by: Fan Du <fan.du@windriver.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* netfilter: remove double colonstephen hemminger2014-02-191-1/+1
| | | | | | | This is C not shell script Signed-off-by: Stephen Hemminger <stephen@networkplumber.org> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller2014-02-1929-173/+362
|\ | | | | | | | | | | | | | | | | | | | | Conflicts: drivers/net/bonding/bond_3ad.h drivers/net/bonding/bond_main.c Two minor conflicts in bonding, both of which were overlapping changes. Signed-off-by: David S. Miller <davem@davemloft.net>
| * Merge branch 'for-linus' of ↵Linus Torvalds2014-02-182-2/+18
| |\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/jikos/hid Pull HID update from Jiri Kosina: - fixes for several bugs in incorrect allocations of buffers by David Herrmann and Benjamin Tissoires. - support for a few new device IDs by Archana Patni, Benjamin Tissoires, Huei-Horng Yo, Reyad Attiyat and Yufeng Shen * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/hid: HID: hyperv: make sure input buffer is big enough HID: Bluetooth: hidp: make sure input buffers are big enough HID: hid-sensor-hub: quirk for STM Sensor hub HID: apple: add Apple wireless keyboard 2011 JIS model support HID: fix buffer allocations HID: multitouch: add FocalTech FTxxxx support HID: microsoft: Add ID's for Surface Type/Touch Cover 2 HID: usbhid: quirk for CY-TM75 75 inch Touch Overlay
| | * HID: Bluetooth: hidp: make sure input buffers are big enoughDavid Herrmann2014-02-172-2/+18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | HID core expects the input buffers to be at least of size 4096 (HID_MAX_BUFFER_SIZE). Other sizes will result in buffer-overflows if an input-report is smaller than advertised. We could, like i2c, compute the biggest report-size instead of using HID_MAX_BUFFER_SIZE, but this will blow up if report-descriptors are changed after ->start() has been called. So lets be safe and just use the biggest buffer we have. Note that this adds an additional copy to the HIDP input path. If there is a way to make sure the skb-buf is big enough, we should use that instead. The best way would be to make hid-core honor the @size argument, though, that sounds easier than it is. So lets just fix the buffer-overflows for now and afterwards look for a faster way for all transport drivers. Signed-off-by: David Herrmann <dh.herrmann@gmail.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
| * | af_packet: remove a stray tab in packet_set_ring()Dan Carpenter2014-02-181-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | At first glance it looks like there is a missing curly brace but actually the code works the same either way. I have adjusted the indenting but left the code the same. Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Acked-by: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * | net: sctp: fix sctp_connectx abi for ia32 emulation/compat modeDaniel Borkmann2014-02-181-9/+32
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | SCTP's sctp_connectx() abi breaks for 64bit kernels compiled with 32bit emulation (e.g. ia32 emulation or x86_x32). Due to internal usage of 'struct sctp_getaddrs_old' which includes a struct sockaddr pointer, sizeof(param) check will always fail in kernel as the structure in 64bit kernel space is 4bytes larger than for user binaries compiled in 32bit mode. Thus, applications making use of sctp_connectx() won't be able to run under such circumstances. Introduce a compat interface in the kernel to deal with such situations by using a 'struct compat_sctp_getaddrs_old' structure where user data is copied into it, and then sucessively transformed into a 'struct sctp_getaddrs_old' structure with the help of compat_ptr(). That fixes sctp_connectx() abi without any changes needed in user space, and lets the SCTP test suite pass when compiled in 32bit and run on 64bit kernels. Fixes: f9c67811ebc0 ("sctp: Fix regression introduced by new sctp_connectx api") Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Acked-by: Vlad Yasevich <vyasevich@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * | Merge tag 'batman-adv-fix-for-davem' of git://git.open-mesh.org/linux-mergeDavid S. Miller2014-02-187-27/+101
| |\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Included changes: - fix soft-interface MTU computation - fix bogus pointer mangling when parsing the TT-TVLV container. This bug led to a wrong memory access. - fix memory leak by properly releasing the VLAN object after CRC check - properly check pskb_may_pull() return value - avoid potential race condition while adding new neighbour - fix potential memory leak by removing all the references to the orig_node object in case of initialization failure - fix the TT CRC computation by ensuring that every node uses the same byte order when hosts with different endianess are part of the same network - fix severe memory leak by freeing skb after a successful TVLV parsing - avoid potential double free when orig_node initialization fails - fix potential kernel paging error caused by the usage of the old value of skb->data after skb reallocation Signed-off-by: David S. Miller <davem@davemloft.net>
| | * | batman-adv: fix potential kernel paging error for unicast transmissionsAntonio Quartulli2014-02-171-2/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | batadv_send_skb_prepare_unicast(_4addr) might reallocate the skb's data. If it does then our ethhdr pointer is not valid anymore in batadv_send_skb_unicast(), resulting in a kernel paging error. Fixing this by refetching the ethhdr pointer after the potential reallocation. Signed-off-by: Linus Lüssing <linus.luessing@web.de> Signed-off-by: Antonio Quartulli <antonio@meshcoding.com>
| | * | batman-adv: avoid double free when orig_node initialization failsAntonio Quartulli2014-02-171-4/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In the failure path of the orig_node initialization routine the orig_node->bat_iv.bcast_own field is free'd twice: first in batadv_iv_ogm_orig_get() and then later in batadv_orig_node_free_rcu(). Fix it by removing the kfree in batadv_iv_ogm_orig_get(). Signed-off-by: Antonio Quartulli <antonio@meshcoding.com> Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
| | * | batman-adv: free skb on TVLV parsing successAntonio Quartulli2014-02-171-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When the TVLV parsing routine succeed the skb is left untouched thus leading to a memory leak. Fix this by consuming the skb in case of success. Introduced by ef26157747d42254453f6b3ac2bd8bd3c53339c3 ("batman-adv: tvlv - basic infrastructure") Reported-by: Russel Senior <russell@personaltelco.net> Signed-off-by: Antonio Quartulli <antonio@open-mesh.com> Tested-by: Russell Senior <russell@personaltelco.net> Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
| | * | batman-adv: fix TT CRC computation by ensuring byte orderAntonio Quartulli2014-02-171-4/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When computing the CRC on a 2byte variable the order of the bytes obviously alters the final result. This means that computing the CRC over the same value on two archs having different endianess leads to different numbers. The global and local translation table CRC computation routine makes this mistake while processing the clients VIDs. The result is a continuous CRC mismatching between nodes having different endianess. Fix this by converting the VID to Network Order before processing it. This guarantees that every node uses the same byte order. Introduced by 7ea7b4a142758deaf46c1af0ca9ceca6dd55138b ("batman-adv: make the TT CRC logic VLAN specific") Reported-by: Russel Senior <russell@personaltelco.net> Signed-off-by: Antonio Quartulli <antonio@open-mesh.com> Tested-by: Russell Senior <russell@personaltelco.net> Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
| | * | batman-adv: fix potential orig_node reference leakSimon Wunderlich2014-02-171-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Since batadv_orig_node_new() sets the refcount to two, assuming that the calling function will use a reference for putting the orig_node into a hash or similar, both references must be freed if initialization of the orig_node fails. Otherwise that object may be leaked in that error case. Reported-by: Antonio Quartulli <antonio@meshcoding.com> Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de> Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch> Signed-off-by: Antonio Quartulli <antonio@meshcoding.com>
| | * | batman-adv: avoid potential race condition when adding a new neighbourAntonio Quartulli2014-02-173-6/+56
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When adding a new neighbour it is important to atomically perform the following: - check if the neighbour already exists - append the neighbour to the proper list If the two operations are not performed in an atomic context it is possible that two concurrent insertions add the same neighbour twice. Signed-off-by: Antonio Quartulli <antonio@open-mesh.com> Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
| | * | batman-adv: properly check pskb_may_pull return valueAntonio Quartulli2014-02-171-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | pskb_may_pull() returns 1 on success and 0 in case of failure, therefore checking for the return value being negative does not make sense at all. This way if the function fails we will probably read beyond the current skb data buffer. Fix this by doing the proper check. Signed-off-by: Antonio Quartulli <antonio@meshcoding.com> Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
| | * | batman-adv: release vlan object after checking the CRCAntonio Quartulli2014-02-171-1/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There is a refcounter unbalance in the CRC checking routine invoked on OGM reception. A vlan object is retrieved (thus its refcounter is increased by one) but it is never properly released. This leads to a memleak because the vlan object will never be free'd. Fix this by releasing the vlan object after having read the CRC. Reported-by: Russell Senior <russell@personaltelco.net> Reported-by: Daniel <daniel@makrotopia.org> Reported-by: cmsv <cmsv@wirelesspt.net> Signed-off-by: Antonio Quartulli <antonio@meshcoding.com> Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
| | * | batman-adv: fix TT-TVLV parsing on OGM receptionAntonio Quartulli2014-02-171-1/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When accessing a TT-TVLV container in the OGM RX path the variable pointing to the list of changes to apply is altered by mistake. This makes the TT component read data at the wrong position in the OGM packet buffer. Fix it by removing the bogus pointer alteration. Signed-off-by: Antonio Quartulli <antonio@meshcoding.com> Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
| | * | batman-adv: fix soft-interface MTU computationAntonio Quartulli2014-02-171-8/+14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The current MTU computation always returns a value smaller than 1500bytes even if the real interfaces have an MTU large enough to compensate the batman-adv overhead. Fix the computation by properly returning the highest admitted value. Introduced by a19d3d85e1b854e4a483a55d740a42458085560d ("batman-adv: limit local translation table max size") Reported-by: Russell Senior <russell@personaltelco.net> Signed-off-by: Antonio Quartulli <antonio@meshcoding.com> Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
| * | | ipv4: fix counter in_slow_totDuan Jiong2014-02-171-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | since commit 89aef8921bf("ipv4: Delete routing cache."), the counter in_slow_tot can't work correctly. The counter in_slow_tot increase by one when fib_lookup() return successfully in ip_route_input_slow(), but actually the dst struct maybe not be created and cached, so we can increase in_slow_tot after the dst struct is created. Signed-off-by: Duan Jiong <duanj.fnst@cn.fujitsu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * | | gre: add link local route when local addr is anyNicolas Dichtel2014-02-171-0/+2
| |/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This bug was reported by Steinar H. Gunderson and was introduced by commit f7cb8886335d ("sit/gre6: don't try to add the same route two times"). root@morgental:~# ip tunnel add foo mode gre remote 1.2.3.4 ttl 64 root@morgental:~# ip link set foo up mtu 1468 root@morgental:~# ip -6 route show dev foo fe80::/64 proto kernel metric 256 but after the above commit, no such route shows up. There is no link local route because dev->dev_addr is 0 (because local ipv4 address is 0), hence no link local address is configured. In this scenario, the link local address is added manually: 'ip -6 addr add fe80::1 dev foo' and because prefix is /128, no link local route is added by the kernel. Even if the right things to do is to add the link local address with a /64 prefix, we need to restore the previous behavior to avoid breaking userpace. Reported-by: Steinar H. Gunderson <sesse@samfundet.no> Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * | packet: check for ndo_select_queue during queue selectionDaniel Borkmann2014-02-171-3/+21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Mathias reported that on an AMD Geode LX embedded board (ALiX) with ath9k driver PACKET_QDISC_BYPASS, introduced in commit d346a3fae3ff ("packet: introduce PACKET_QDISC_BYPASS socket option"), triggers a WARN_ON() coming from the driver itself via 066dae93bdf ("ath9k: rework tx queue selection and fix queue stopping/waking"). The reason why this happened is that ndo_select_queue() call is not invoked from direct xmit path i.e. for ieee80211 subsystem that sets queue and TID (similar to 802.1d tag) which is being put into the frame through 802.11e (WMM, QoS). If that is not set, pending frame counter for e.g. ath9k can get messed up. So the WARN_ON() in ath9k is absolutely legitimate. Generally, the hw queue selection in ieee80211 depends on the type of traffic, and priorities are set according to ieee80211_ac_numbers mapping; working in a similar way as DiffServ only on a lower layer, so that the AP can favour frames that have "real-time" requirements like voice or video data frames. Therefore, check for presence of ndo_select_queue() in netdev ops and, if available, invoke it with a fallback handler to __packet_pick_tx_queue(), so that driver such as bnx2x, ixgbe, or mlx4 can still select a hw queue for transmission in relation to the current CPU while e.g. ieee80211 subsystem can make their own choices. Reported-by: Mathias Kretschmer <mathias.kretschmer@fokus.fraunhofer.de> Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Cc: Jesper Dangaard Brouer <brouer@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * | netdevice: move netdev_cap_txqueue for shared usage to headerDaniel Borkmann2014-02-171-12/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | In order to allow users to invoke netdev_cap_txqueue, it needs to be moved into netdevice.h header file. While at it, also add kernel doc header to document the API. Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * | netdevice: add queue selection fallback handler for ndo_select_queueDaniel Borkmann2014-02-172-6/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add a new argument for ndo_select_queue() callback that passes a fallback handler. This gets invoked through netdev_pick_tx(); fallback handler is currently __netdev_pick_tx() as most drivers invoke this function within their customized implementation in case for skbs that don't need any special handling. This fallback handler can then be replaced on other call-sites with different queue selection methods (e.g. in packet sockets, pktgen etc). This also has the nice side-effect that __netdev_pick_tx() is then only invoked from netdev_pick_tx() and export of that function to modules can be undone. Suggested-by: David S. Miller <davem@davemloft.net> Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * | net: sctp: Fix a_rwnd/rwnd management to reflect real state of the ↵Matija Glavinic Pecotic2014-02-174-74/+24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | receiver's buffer Implementation of (a)rwnd calculation might lead to severe performance issues and associations completely stalling. These problems are described and solution is proposed which improves lksctp's robustness in congestion state. 1) Sudden drop of a_rwnd and incomplete window recovery afterwards Data accounted in sctp_assoc_rwnd_decrease takes only payload size (sctp data), but size of sk_buff, which is blamed against receiver buffer, is not accounted in rwnd. Theoretically, this should not be the problem as actual size of buffer is double the amount requested on the socket (SO_RECVBUF). Problem here is that this will have bad scaling for data which is less then sizeof sk_buff. E.g. in 4G (LTE) networks, link interfacing radio side will have a large portion of traffic of this size (less then 100B). An example of sudden drop and incomplete window recovery is given below. Node B exhibits problematic behavior. Node A initiates association and B is configured to advertise rwnd of 10000. A sends messages of size 43B (size of typical sctp message in 4G (LTE) network). On B data is left in buffer by not reading socket in userspace. Lets examine when we will hit pressure state and declare rwnd to be 0 for scenario with above stated parameters (rwnd == 10000, chunk size == 43, each chunk is sent in separate sctp packet) Logic is implemented in sctp_assoc_rwnd_decrease: socket_buffer (see below) is maximum size which can be held in socket buffer (sk_rcvbuf). current_alloced is amount of data currently allocated (rx_count) A simple expression is given for which it will be examined after how many packets for above stated parameters we enter pressure state: We start by condition which has to be met in order to enter pressure state: socket_buffer < currently_alloced; currently_alloced is represented as size of sctp packets received so far and not yet delivered to userspace. x is the number of chunks/packets (since there is no bundling, and each chunk is delivered in separate packet, we can observe each chunk also as sctp packet, and what is important here, having its own sk_buff): socket_buffer < x*each_sctp_packet; each_sctp_packet is sctp chunk size + sizeof(struct sk_buff). socket_buffer is twice the amount of initially requested size of socket buffer, which is in case of sctp, twice the a_rwnd requested: 2*rwnd < x*(payload+sizeof(struc sk_buff)); sizeof(struct sk_buff) is 190 (3.13.0-rc4+). Above is stated that rwnd is 10000 and each payload size is 43 20000 < x(43+190); x > 20000/233; x ~> 84; After ~84 messages, pressure state is entered and 0 rwnd is advertised while received 84*43B ~= 3612B sctp data. This is why external observer notices sudden drop from 6474 to 0, as it will be now shown in example: IP A.34340 > B.12345: sctp (1) [INIT] [init tag: 1875509148] [rwnd: 81920] [OS: 10] [MIS: 65535] [init TSN: 1096057017] IP B.12345 > A.34340: sctp (1) [INIT ACK] [init tag: 3198966556] [rwnd: 10000] [OS: 10] [MIS: 10] [init TSN: 902132839] IP A.34340 > B.12345: sctp (1) [COOKIE ECHO] IP B.12345 > A.34340: sctp (1) [COOKIE ACK] IP A.34340 > B.12345: sctp (1) [DATA] (B)(E) [TSN: 1096057017] [SID: 0] [SSEQ 0] [PPID 0x18] IP B.12345 > A.34340: sctp (1) [SACK] [cum ack 1096057017] [a_rwnd 9957] [#gap acks 0] [#dup tsns 0] IP A.34340 > B.12345: sctp (1) [DATA] (B)(E) [TSN: 1096057018] [SID: 0] [SSEQ 1] [PPID 0x18] IP B.12345 > A.34340: sctp (1) [SACK] [cum ack 1096057018] [a_rwnd 9957] [#gap acks 0] [#dup tsns 0] IP A.34340 > B.12345: sctp (1) [DATA] (B)(E) [TSN: 1096057019] [SID: 0] [SSEQ 2] [PPID 0x18] IP B.12345 > A.34340: sctp (1) [SACK] [cum ack 1096057019] [a_rwnd 9914] [#gap acks 0] [#dup tsns 0] <...> IP A.34340 > B.12345: sctp (1) [DATA] (B)(E) [TSN: 1096057098] [SID: 0] [SSEQ 81] [PPID 0x18] IP B.12345 > A.34340: sctp (1) [SACK] [cum ack 1096057098] [a_rwnd 6517] [#gap acks 0] [#dup tsns 0] IP A.34340 > B.12345: sctp (1) [DATA] (B)(E) [TSN: 1096057099] [SID: 0] [SSEQ 82] [PPID 0x18] IP B.12345 > A.34340: sctp (1) [SACK] [cum ack 1096057099] [a_rwnd 6474] [#gap acks 0] [#dup tsns 0] IP A.34340 > B.12345: sctp (1) [DATA] (B)(E) [TSN: 1096057100] [SID: 0] [SSEQ 83] [PPID 0x18] --> Sudden drop IP B.12345 > A.34340: sctp (1) [SACK] [cum ack 1096057100] [a_rwnd 0] [#gap acks 0] [#dup tsns 0] At this point, rwnd_press stores current rwnd value so it can be later restored in sctp_assoc_rwnd_increase. This however doesn't happen as condition to start slowly increasing rwnd until rwnd_press is returned to rwnd is never met. This condition is not met since rwnd, after it hit 0, must first reach rwnd_press by adding amount which is read from userspace. Let us observe values in above example. Initial a_rwnd is 10000, pressure was hit when rwnd was ~6500 and the amount of actual sctp data currently waiting to be delivered to userspace is ~3500. When userspace starts to read, sctp_assoc_rwnd_increase will be blamed only for sctp data, which is ~3500. Condition is never met, and when userspace reads all data, rwnd stays on 3569. IP B.12345 > A.34340: sctp (1) [SACK] [cum ack 1096057100] [a_rwnd 1505] [#gap acks 0] [#dup tsns 0] IP B.12345 > A.34340: sctp (1) [SACK] [cum ack 1096057100] [a_rwnd 3010] [#gap acks 0] [#dup tsns 0] IP A.34340 > B.12345: sctp (1) [DATA] (B)(E) [TSN: 1096057101] [SID: 0] [SSEQ 84] [PPID 0x18] IP B.12345 > A.34340: sctp (1) [SACK] [cum ack 1096057101] [a_rwnd 3569] [#gap acks 0] [#dup tsns 0] --> At this point userspace read everything, rwnd recovered only to 3569 IP A.34340 > B.12345: sctp (1) [DATA] (B)(E) [TSN: 1096057102] [SID: 0] [SSEQ 85] [PPID 0x18] IP B.12345 > A.34340: sctp (1) [SACK] [cum ack 1096057102] [a_rwnd 3569] [#gap acks 0] [#dup tsns 0] Reproduction is straight forward, it is enough for sender to send packets of size less then sizeof(struct sk_buff) and receiver keeping them in its buffers. 2) Minute size window for associations sharing the same socket buffer In case multiple associations share the same socket, and same socket buffer (sctp.rcvbuf_policy == 0), different scenarios exist in which congestion on one of the associations can permanently drop rwnd of other association(s). Situation will be typically observed as one association suddenly having rwnd dropped to size of last packet received and never recovering beyond that point. Different scenarios will lead to it, but all have in common that one of the associations (let it be association from 1)) nearly depleted socket buffer, and the other association blames socket buffer just for the amount enough to start the pressure. This association will enter pressure state, set rwnd_press and announce 0 rwnd. When data is read by userspace, similar situation as in 1) will occur, rwnd will increase just for the size read by userspace but rwnd_press will be high enough so that association doesn't have enough credit to reach rwnd_press and restore to previous state. This case is special case of 1), being worse as there is, in the worst case, only one packet in buffer for which size rwnd will be increased. Consequence is association which has very low maximum rwnd ('minute size', in our case down to 43B - size of packet which caused pressure) and as such unusable. Scenario happened in the field and labs frequently after congestion state (link breaks, different probabilities of packet drop, packet reordering) and with scenario 1) preceding. Here is given a deterministic scenario for reproduction: >From node A establish two associations on the same socket, with rcvbuf_policy being set to share one common buffer (sctp.rcvbuf_policy == 0). On association 1 repeat scenario from 1), that is, bring it down to 0 and restore up. Observe scenario 1). Use small payload size (here we use 43). Once rwnd is 'recovered', bring it down close to 0, as in just one more packet would close it. This has as a consequence that association number 2 is able to receive (at least) one more packet which will bring it in pressure state. E.g. if association 2 had rwnd of 10000, packet received was 43, and we enter at this point into pressure, rwnd_press will have 9957. Once payload is delivered to userspace, rwnd will increase for 43, but conditions to restore rwnd to original state, just as in 1), will never be satisfied. --> Association 1, between A.y and B.12345 IP A.55915 > B.12345: sctp (1) [INIT] [init tag: 836880897] [rwnd: 10000] [OS: 10] [MIS: 65535] [init TSN: 4032536569] IP B.12345 > A.55915: sctp (1) [INIT ACK] [init tag: 2873310749] [rwnd: 81920] [OS: 10] [MIS: 10] [init TSN: 3799315613] IP A.55915 > B.12345: sctp (1) [COOKIE ECHO] IP B.12345 > A.55915: sctp (1) [COOKIE ACK] --> Association 2, between A.z and B.12346 IP A.55915 > B.12346: sctp (1) [INIT] [init tag: 534798321] [rwnd: 10000] [OS: 10] [MIS: 65535] [init TSN: 2099285173] IP B.12346 > A.55915: sctp (1) [INIT ACK] [init tag: 516668823] [rwnd: 81920] [OS: 10] [MIS: 10] [init TSN: 3676403240] IP A.55915 > B.12346: sctp (1) [COOKIE ECHO] IP B.12346 > A.55915: sctp (1) [COOKIE ACK] --> Deplete socket buffer by sending messages of size 43B over association 1 IP B.12345 > A.55915: sctp (1) [DATA] (B)(E) [TSN: 3799315613] [SID: 0] [SSEQ 0] [PPID 0x18] IP A.55915 > B.12345: sctp (1) [SACK] [cum ack 3799315613] [a_rwnd 9957] [#gap acks 0] [#dup tsns 0] <...> IP A.55915 > B.12345: sctp (1) [SACK] [cum ack 3799315696] [a_rwnd 6388] [#gap acks 0] [#dup tsns 0] IP B.12345 > A.55915: sctp (1) [DATA] (B)(E) [TSN: 3799315697] [SID: 0] [SSEQ 84] [PPID 0x18] IP A.55915 > B.12345: sctp (1) [SACK] [cum ack 3799315697] [a_rwnd 6345] [#gap acks 0] [#dup tsns 0] --> Sudden drop on 1 IP B.12345 > A.55915: sctp (1) [DATA] (B)(E) [TSN: 3799315698] [SID: 0] [SSEQ 85] [PPID 0x18] IP A.55915 > B.12345: sctp (1) [SACK] [cum ack 3799315698] [a_rwnd 0] [#gap acks 0] [#dup tsns 0] --> Here userspace read, rwnd 'recovered' to 3698, now deplete again using association 1 so there is place in buffer for only one more packet IP B.12345 > A.55915: sctp (1) [DATA] (B)(E) [TSN: 3799315799] [SID: 0] [SSEQ 186] [PPID 0x18] IP A.55915 > B.12345: sctp (1) [SACK] [cum ack 3799315799] [a_rwnd 86] [#gap acks 0] [#dup tsns 0] IP B.12345 > A.55915: sctp (1) [DATA] (B)(E) [TSN: 3799315800] [SID: 0] [SSEQ 187] [PPID 0x18] IP A.55915 > B.12345: sctp (1) [SACK] [cum ack 3799315800] [a_rwnd 43] [#gap acks 0] [#dup tsns 0] --> Socket buffer is almost depleted, but there is space for one more packet, send them over association 2, size 43B IP B.12346 > A.55915: sctp (1) [DATA] (B)(E) [TSN: 3676403240] [SID: 0] [SSEQ 0] [PPID 0x18] IP A.55915 > B.12346: sctp (1) [SACK] [cum ack 3676403240] [a_rwnd 0] [#gap acks 0] [#dup tsns 0] --> Immediate drop IP A.60995 > B.12346: sctp (1) [SACK] [cum ack 387491510] [a_rwnd 0] [#gap acks 0] [#dup tsns 0] --> Read everything from the socket, both association recover up to maximum rwnd they are capable of reaching, note that association 1 recovered up to 3698, and association 2 recovered only to 43 IP A.55915 > B.12345: sctp (1) [SACK] [cum ack 3799315800] [a_rwnd 1548] [#gap acks 0] [#dup tsns 0] IP A.55915 > B.12345: sctp (1) [SACK] [cum ack 3799315800] [a_rwnd 3053] [#gap acks 0] [#dup tsns 0] IP B.12345 > A.55915: sctp (1) [DATA] (B)(E) [TSN: 3799315801] [SID: 0] [SSEQ 188] [PPID 0x18] IP A.55915 > B.12345: sctp (1) [SACK] [cum ack 3799315801] [a_rwnd 3698] [#gap acks 0] [#dup tsns 0] IP B.12346 > A.55915: sctp (1) [DATA] (B)(E) [TSN: 3676403241] [SID: 0] [SSEQ 1] [PPID 0x18] IP A.55915 > B.12346: sctp (1) [SACK] [cum ack 3676403241] [a_rwnd 43] [#gap acks 0] [#dup tsns 0] A careful reader might wonder why it is necessary to reproduce 1) prior reproduction of 2). It is simply easier to observe when to send packet over association 2 which will push association into the pressure state. Proposed solution: Both problems share the same root cause, and that is improper scaling of socket buffer with rwnd. Solution in which sizeof(sk_buff) is taken into concern while calculating rwnd is not possible due to fact that there is no linear relationship between amount of data blamed in increase/decrease with IP packet in which payload arrived. Even in case such solution would be followed, complexity of the code would increase. Due to nature of current rwnd handling, slow increase (in sctp_assoc_rwnd_increase) of rwnd after pressure state is entered is rationale, but it gives false representation to the sender of current buffer space. Furthermore, it implements additional congestion control mechanism which is defined on implementation, and not on standard basis. Proposed solution simplifies whole algorithm having on mind definition from rfc: o Receiver Window (rwnd): This gives the sender an indication of the space available in the receiver's inbound buffer. Core of the proposed solution is given with these lines: sctp_assoc_rwnd_update: if ((asoc->base.sk->sk_rcvbuf - rx_count) > 0) asoc->rwnd = (asoc->base.sk->sk_rcvbuf - rx_count) >> 1; else asoc->rwnd = 0; We advertise to sender (half of) actual space we have. Half is in the braces depending whether you would like to observe size of socket buffer as SO_RECVBUF or twice the amount, i.e. size is the one visible from userspace, that is, from kernelspace. In this way sender is given with good approximation of our buffer space, regardless of the buffer policy - we always advertise what we have. Proposed solution fixes described problems and removes necessity for rwnd restoration algorithm. Finally, as proposed solution is simplification, some lines of code, along with some bytes in struct sctp_association are saved. Version 2 of the patch addressed comments from Vlad. Name of the function is set to be more descriptive, and two parts of code are changed, in one removing the superfluous call to sctp_assoc_rwnd_update since call would not result in update of rwnd, and the other being reordering of the code in a way that call to sctp_assoc_rwnd_update updates rwnd. Version 3 corrected change introduced in v2 in a way that existing function is not reordered/copied in line, but it is correctly called. Thanks Vlad for suggesting. Signed-off-by: Matija Glavinic Pecotic <matija.glavinic-pecotic.ext@nsn.com> Reviewed-by: Alexander Sverdlin <alexander.sverdlin@nsn.com> Acked-by: Vlad Yasevich <vyasevich@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * | ipv4: distinguish EHOSTUNREACH from the ENETUNREACHDuan Jiong2014-02-161-2/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | since commit 251da413("ipv4: Cache ip_error() routes even when not forwarding."), the counter IPSTATS_MIB_INADDRERRORS can't work correctly, because the value of err was always set to ENETUNREACH. Signed-off-by: Duan Jiong <duanj.fnst@cn.fujitsu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * | dccp: re-enable debug macroGerrit Renker2014-02-162-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | dccp tfrc: revert This reverts 6aee49c558de ("dccp: make local variable static") since the variable tfrc_debug is referenced by the tfrc_pr_debug(fmt, ...) macro when TFRC debugging is enabled. If it is enabled, use of the macro produces a compilation error. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Signed-off-by: David S. Miller <davem@davemloft.net>
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