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path: root/net/netfilter/nf_conntrack_netlink.c
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2010-02-19netfilter: ctnetlink: fix creation of conntrack with helpersPablo Neira Ayuso
This patch fixes a bug that triggers an assertion if you create a conntrack entry with a helper and netfilter debugging is enabled. Basically, we hit the assertion because the confirmation flag is set before the conntrack extensions are added. To fix this, we move the extension addition before the aforementioned flag is set. This patch also removes the possibility of setting a helper for existing conntracks. This operation would also trigger the assertion since we are not allowed to add new extensions for existing conntracks. We know noone that could benefit from this operation sanely. Thanks to Eric Dumazet for initial posting a preliminary patch to address this issue. Reported-by: David Ramblewski <David.Ramblewski@atosorigin.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: Patrick McHardy <kaber@trash.net>
2010-02-15netfilter: ctnetlink: add zone supportPatrick McHardy
Parse and dump the conntrack zone in ctnetlink. Signed-off-by: Patrick McHardy <kaber@trash.net>
2010-02-15netfilter: nf_conntrack: add support for "conntrack zones"Patrick McHardy
Normally, each connection needs a unique identity. Conntrack zones allow to specify a numerical zone using the CT target, connections in different zones can use the same identity. Example: iptables -t raw -A PREROUTING -i veth0 -j CT --zone 1 iptables -t raw -A OUTPUT -o veth1 -j CT --zone 1 Signed-off-by: Patrick McHardy <kaber@trash.net>
2010-02-11netfilter: ctnetlink: dump expectation helper namePatrick McHardy
Signed-off-by: Patrick McHardy <kaber@trash.net>
2010-02-10netfilter: ctnetlink: add missing netlink attribute policiesPatrick McHardy
Signed-off-by: Patrick McHardy <kaber@trash.net>
2010-02-10Merge branch 'master' of /repos/git/net-next-2.6Patrick McHardy
Signed-off-by: Patrick McHardy <kaber@trash.net>
2010-02-08netfilter: nf_conntrack: fix hash resizing with namespacesPatrick McHardy
As noticed by Jon Masters <jonathan@jonmasters.org>, the conntrack hash size is global and not per namespace, but modifiable at runtime through /sys/module/nf_conntrack/hashsize. Changing the hash size will only resize the hash in the current namespace however, so other namespaces will use an invalid hash size. This can cause crashes when enlarging the hashsize, or false negative lookups when shrinking it. Move the hash size into the per-namespace data and only use the global hash size to initialize the per-namespace value when instanciating a new namespace. Additionally restrict hash resizing to init_net for now as other namespaces are not handled currently. Cc: stable@kernel.org Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-02-03netfilter: nf_conntrack: support conntrack templatesPatrick McHardy
Support initializing selected parameters of new conntrack entries from a "conntrack template", which is a specially marked conntrack entry attached to the skb. Currently the helper and the event delivery masks can be initialized this way. Signed-off-by: Patrick McHardy <kaber@trash.net>
2010-02-03netfilter: ctnetlink: support selective event deliveryPatrick McHardy
Add two masks for conntrack end expectation events to struct nf_conntrack_ecache and use them to filter events. Their default value is "all events" when the event sysctl is on and "no events" when it is off. A following patch will add specific initializations. Expectation events depend on the ecache struct of their master conntrack. Signed-off-by: Patrick McHardy <kaber@trash.net>
2010-02-03netfilter: nf_conntrack: split up IPCT_STATUS eventPatrick McHardy
Split up the IPCT_STATUS event into an IPCT_REPLY event, which is generated when the IPS_SEEN_REPLY bit is set, and an IPCT_ASSURED event, which is generated when the IPS_ASSURED bit is set. In combination with a following patch to support selective event delivery, this can be used for "sparse" conntrack replication: start replicating the conntrack entry after it reached the ASSURED state and that way it's SYN-flood resistant. Signed-off-by: Patrick McHardy <kaber@trash.net>
2010-02-03netfilter: ctnetlink: only assign helpers for matching protocolsPatrick McHardy
Make sure not to assign a helper for a different network or transport layer protocol to a connection. Additionally change expectation deletion by helper to compare the name directly - there might be multiple helper registrations using the same name, currently one of them is chosen in an unpredictable manner and only those expectations are removed. Signed-off-by: Patrick McHardy <kaber@trash.net>
2010-01-26netfilter: ctnetlink: fix expectation mask dumpPatrick McHardy
The protocol number is not initialized, so userspace can't interpret the layer 4 data properly. Signed-off-by: Patrick McHardy <kaber@trash.net>
2010-01-13netfilter: ctnetlink: netns supportAlexey Dobriyan
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Patrick McHardy <kaber@trash.net>
2010-01-13netfilter: nfnetlink: netns supportAlexey Dobriyan
Make nfnl socket per-petns. Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Patrick McHardy <kaber@trash.net>
2009-08-25netfilter: nfnetlink: constify message attributes and headersPatrick McHardy
Signed-off-by: Patrick McHardy <kaber@trash.net>
2009-06-13netfilter: conntrack: optional reliable conntrack event deliveryPablo Neira Ayuso
This patch improves ctnetlink event reliability if one broadcast listener has set the NETLINK_BROADCAST_ERROR socket option. The logic is the following: if an event delivery fails, we keep the undelivered events in the missed event cache. Once the next packet arrives, we add the new events (if any) to the missed events in the cache and we try a new delivery, and so on. Thus, if ctnetlink fails to deliver an event, we try to deliver them once we see a new packet. Therefore, we may lose state transitions but the userspace process gets in sync at some point. At worst case, if no events were delivered to userspace, we make sure that destroy events are successfully delivered. Basically, if ctnetlink fails to deliver the destroy event, we remove the conntrack entry from the hashes and we insert them in the dying list, which contains inactive entries. Then, the conntrack timer is added with an extra grace timeout of random32() % 15 seconds to trigger the event again (this grace timeout is tunable via /proc). The use of a limited random timeout value allows distributing the "destroy" resends, thus, avoiding accumulating lots "destroy" events at the same time. Event delivery may re-order but we can identify them by means of the tuple plus the conntrack ID. The maximum number of conntrack entries (active or inactive) is still handled by nf_conntrack_max. Thus, we may start dropping packets at some point if we accumulate a lot of inactive conntrack entries that did not successfully report the destroy event to userspace. During my stress tests consisting of setting a very small buffer of 2048 bytes for conntrackd and the NETLINK_BROADCAST_ERROR socket flag, and generating lots of very small connections, I noticed very few destroy entries on the fly waiting to be resend. A simple way to test this patch consist of creating a lot of entries, set a very small Netlink buffer in conntrackd (+ a patch which is not in the git tree to set the BROADCAST_ERROR flag) and invoke `conntrack -F'. For expectations, no changes are introduced in this patch. Currently, event delivery is only done for new expectations (no events from expectation expiration, removal and confirmation). In that case, they need a per-expectation event cache to implement the same idea that is exposed in this patch. This patch can be useful to provide reliable flow-accouting. We still have to add a new conntrack extension to store the creation and destroy time. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Patrick McHardy <kaber@trash.net>
2009-06-13netfilter: conntrack: move event caching to conntrack extension infrastructurePablo Neira Ayuso
This patch reworks the per-cpu event caching to use the conntrack extension infrastructure. The main drawback is that we consume more memory per conntrack if event delivery is enabled. This patch is required by the reliable event delivery that follows to this patch. BTW, this patch allows you to enable/disable event delivery via /proc/sys/net/netfilter/nf_conntrack_events in runtime, although you can still disable event caching as compilation option. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Patrick McHardy <kaber@trash.net>
2009-06-10netfilter: nf_conntrack: use per-conntrack locks for protocol dataPatrick McHardy
Introduce per-conntrack locks and use them instead of the global protocol locks to avoid contention. Especially tcp_lock shows up very high in profiles on larger machines. This will also allow to simplify the upcoming reliable event delivery patches. Signed-off-by: Patrick McHardy <kaber@trash.net>
2009-06-03netfilter: conntrack: replace notify chain by function pointerPablo Neira Ayuso
This patch removes the notify chain infrastructure and replace it by a simple function pointer. This issue has been mentioned in the mailing list several times: the use of the notify chain adds too much overhead for something that is only used by ctnetlink. This patch also changes nfnetlink_send(). It seems that gfp_any() returns GFP_KERNEL for user-context request, like those via ctnetlink, inside the RCU read-side section which is not valid. Using GFP_KERNEL is also evil since netlink may schedule(), this leads to "scheduling while atomic" bug reports. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2009-06-02netfilter: conntrack: simplify event caching systemPablo Neira Ayuso
This patch simplifies the conntrack event caching system by removing several events: * IPCT_[*]_VOLATILE, IPCT_HELPINFO and IPCT_NATINFO has been deleted since the have no clients. * IPCT_COUNTER_FILLING which is a leftover of the 32-bits counter days. * IPCT_REFRESH which is not of any use since we always include the timeout in the messages. After this patch, the existing events are: * IPCT_NEW, IPCT_RELATED and IPCT_DESTROY, that are used to identify addition and deletion of entries. * IPCT_STATUS, that notes that the status bits have changes, eg. IPS_SEEN_REPLY and IPS_ASSURED. * IPCT_PROTOINFO, that reports that internal protocol information has changed, eg. the TCP, DCCP and SCTP protocol state. * IPCT_HELPER, that a helper has been assigned or unassigned to this entry. * IPCT_MARK and IPCT_SECMARK, that reports that the mark has changed, this covers the case when a mark is set to zero. * IPCT_NATSEQADJ, to report that there's updates in the NAT sequence adjustment. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2009-06-02netfilter: conntrack: don't report events on module removalPablo Neira Ayuso
During the module removal there are no possible event listeners since ctnetlink must be removed before to allow removing nf_conntrack. This patch removes the event reporting for the module removal case which is not of any use in the existing code. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2009-06-02netfilter: ctnetlink: cleanup message-size calculationPablo Neira Ayuso
This patch cleans up the message calculation to make it similar to rtnetlink, moreover, it removes unneeded verbose information. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2009-06-02netfilter: ctnetlink: use nlmsg_* helper function to build messagesPablo Neira Ayuso
Replaces the old macros to build Netlink messages with the new nlmsg_*() helper functions. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2009-06-02netfilter: ctnetlink: rename tuple() by nf_ct_tuple() macro definitionPablo Neira Ayuso
This patch move the internal tuple() macro definition to the header file as nf_ct_tuple(). Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2009-06-02netfilter: ctnetlink: remove nowait parameter from *fill_info()Pablo Neira Ayuso
This patch is a cleanup, it removes the `nowait' parameter from all *fill_info() function since it is always set to one. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2009-05-05Merge branch 'master' of ↵David S. Miller
git://git.kernel.org/pub/scm/linux/kernel/git/kaber/nf-2.6
2009-05-05netfilter: ctnetlink: fix wrong message type in user updatesPablo Neira Ayuso
This patch fixes the wrong message type that are triggered by user updates, the following commands: (term1)# conntrack -I -p tcp -s 1.1.1.1 -d 2.2.2.2 -t 10 --sport 10 --dport 20 --state LISTEN (term1)# conntrack -U -p tcp -s 1.1.1.1 -d 2.2.2.2 -t 10 --sport 10 --dport 20 --state SYN_SENT (term1)# conntrack -U -p tcp -s 1.1.1.1 -d 2.2.2.2 -t 10 --sport 10 --dport 20 --state SYN_RECV only trigger event message of type NEW, when only the first is NEW while others should be UPDATE. (term2)# conntrack -E [NEW] tcp 6 10 LISTEN src=1.1.1.1 dst=2.2.2.2 sport=10 dport=20 [UNREPLIED] src=2.2.2.2 dst=1.1.1.1 sport=20 dport=10 mark=0 [NEW] tcp 6 10 SYN_SENT src=1.1.1.1 dst=2.2.2.2 sport=10 dport=20 [UNREPLIED] src=2.2.2.2 dst=1.1.1.1 sport=20 dport=10 mark=0 [NEW] tcp 6 10 SYN_RECV src=1.1.1.1 dst=2.2.2.2 sport=10 dport=20 [UNREPLIED] src=2.2.2.2 dst=1.1.1.1 sport=20 dport=10 mark=0 This patch also removes IPCT_REFRESH from the bitmask since it is not of any use. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Patrick McHardy <kaber@trash.net>
2009-04-22netfilter: ctnetlink: fix gcc warning during compilationPablo Neira Ayuso
This patch fixes a (bogus?) gcc warning during compilation: net/netfilter/nf_conntrack_netlink.c:1234: warning: 'helpname' may be used uninitialized in this function net/netfilter/nf_conntrack_netlink.c:991: warning: 'helpname' may be used uninitialized in this function In fact, helpname is initialized by ctnetlink_parse_help() so I cannot see a way to use it without being initialized. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-04-17netfilter: ctnetlink: report error if event message allocation failsPablo Neira Ayuso
This patch fixes an inconsistency that results in no error reports to user-space listeners if we fail to allocate the event message. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Patrick McHardy <kaber@trash.net>
2009-03-27Merge branch 'master' of ↵David S. Miller
git://git.kernel.org/pub/scm/linux/kernel/git/kaber/nf-next-2.6
2009-03-26ctnetlink: compute generic part of event more acuratelyHolger Eitzenberger
On a box with most of the optional Netfilter switches turned off some of the NLAs are never send, e. g. secmark, mark or the conntrack byte/packet counters. As a worst case scenario this may possibly still lead to ctnetlink skbs being reallocated in netlink_trim() later, loosing all the nice effects from the previous patches. I try to solve that (at least partly) by correctly #ifdef'ing the NLAs in the computation. Signed-off-by: Holger Eitzenberger <holger@eitzenberger.org> Signed-off-by: Patrick McHardy <kaber@trash.net>
2009-03-25netfilter: ctnetlink: allocate right-sized ctnetlink skbHolger Eitzenberger
Try to allocate a Netlink skb roughly the size of the actual message, with the help from the l3 and l4 protocol helpers. This is all to prevent a reallocation in netlink_trim() later. The overhead of allocating the right-sized skb is rather small, with ctnetlink_alloc_skb() actually being inlined away on my x86_64 box. The size of the per-proto space is determined at registration time of the protocol helper. Signed-off-by: Holger Eitzenberger <holger@eitzenberger.org> Signed-off-by: Patrick McHardy <kaber@trash.net>
2009-03-25netfilter: nf_conntrack: use SLAB_DESTROY_BY_RCU and get rid of call_rcu()Eric Dumazet
Use "hlist_nulls" infrastructure we added in 2.6.29 for RCUification of UDP & TCP. This permits an easy conversion from call_rcu() based hash lists to a SLAB_DESTROY_BY_RCU one. Avoiding call_rcu() delay at nf_conn freeing time has numerous gains. First, it doesnt fill RCU queues (up to 10000 elements per cpu). This reduces OOM possibility, if queued elements are not taken into account This reduces latency problems when RCU queue size hits hilimit and triggers emergency mode. - It allows fast reuse of just freed elements, permitting better use of CPU cache. - We delete rcu_head from "struct nf_conn", shrinking size of this structure by 8 or 16 bytes. This patch only takes care of "struct nf_conn". call_rcu() is still used for less critical conntrack parts, that may be converted later if necessary. Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: Patrick McHardy <kaber@trash.net>
2009-03-24Merge branch 'master' of ↵David S. Miller
git://git.kernel.org/pub/scm/linux/kernel/git/kaber/nf-next-2.6
2009-03-23nefilter: nfnetlink: add nfnetlink_set_err and use it in ctnetlinkPablo Neira Ayuso
This patch adds nfnetlink_set_err() to propagate the error to netlink broadcast listener in case of memory allocation errors in the message building. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Patrick McHardy <kaber@trash.net>
2009-03-18netfilter: ctnetlink: fix rcu context imbalancePatrick McHardy
Introduced by 7ec47496 (netfilter: ctnetlink: cleanup master conntrack assignation): net/netfilter/nf_conntrack_netlink.c:1275:2: warning: context imbalance in 'ctnetlink_create_conntrack' - different lock contexts for basic block Signed-off-by: Patrick McHardy <kaber@trash.net>
2009-03-18netfilter: ctnetlink: remove remaining module refcountingFlorian Westphal
Convert the remaining refcount users. As pointed out by Patrick McHardy, the protocols can be accessed safely using RCU. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Patrick McHardy <kaber@trash.net>
2009-03-16netfilter: ctnetlink: fix crash during expectation creationPablo Neira Ayuso
This patch fixes a possible crash due to the missing initialization of the expectation class when nf_ct_expect_related() is called. Reported-by: BORBELY Zoltan <bozo@andrews.hu> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Patrick McHardy <kaber@trash.net>
2009-03-16netfilter: ctnetlink: move event reporting for new entries outside the lockPablo Neira Ayuso
This patch moves the event reporting outside the lock section. With this patch, the creation and update of entries is homogeneous from the event reporting perspective. Moreover, as the event reporting is done outside the lock section, the netlink broadcast delivery can benefit of the yield() call under congestion. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Patrick McHardy <kaber@trash.net>
2009-03-16netfilter: ctnetlink: cleanup conntrack update preliminary checkingsPablo Neira Ayuso
This patch moves the preliminary checkings that must be fulfilled to update a conntrack, which are the following: * NAT manglings cannot be updated * Changing the master conntrack is not allowed. This patch is a cleanup. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Patrick McHardy <kaber@trash.net>
2009-03-16netfilter: ctnetlink: cleanup master conntrack assignationPablo Neira Ayuso
This patch moves the assignation of the master conntrack to ctnetlink_create_conntrack(), which is where it really belongs. This patch is a cleanup. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Patrick McHardy <kaber@trash.net>
2009-02-09netfilter: ctnetlink: fix echo if not subscribed to any multicast groupPablo Neira Ayuso
This patch fixes echoing if the socket that has sent the request to create/update/delete an entry is not subscribed to any multicast group. With the current code, ctnetlink would not send the echo message via unicast as nfnetlink_send() would be skip. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-02-09netfilter: ctnetlink: allow changing NAT sequence adjustment in creationPablo Neira Ayuso
This patch fixes an inconsistency in the current ctnetlink code since NAT sequence adjustment bit can only be updated but not set in the conntrack entry creation. This patch is used by conntrackd to successfully recover newly created entries that represent connections with helpers and NAT payload mangling. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-01-21netfilter: ctnetlink: fix scheduling while atomicPatrick McHardy
Caused by call to request_module() while holding nf_conntrack_lock. Reported-and-tested-by: Kövesdi György <kgy@teledigit.hu> Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-01-13netfilter 07/09: simplify nf_conntrack_alloc() error handlingJulia Lawall
nf_conntrack_alloc cannot return NULL, so there is no need to check for NULL before using the value. I have also removed the initialization of ct to NULL in nf_conntrack_alloc, since the value is never used, and since perhaps it might lead one to think that return ct at the end might return NULL. The semantic patch that finds this problem is as follows: (http://www.emn.fr/x-info/coccinelle/) // <smpl> @match exists@ expression x, E; position p1,p2; statement S1, S2; @@ x@p1 = nf_conntrack_alloc(...) ... when != x = E ( if (x@p2 == NULL || ...) S1 else S2 | if (x@p2 == NULL && ...) S1 else S2 ) @other_match exists@ expression match.x, E1, E2; position p1!=match.p1,match.p2; @@ x@p1 = E1 ... when != x = E2 x@p2 @ script:python depends on !other_match@ p1 << match.p1; p2 << match.p2; @@ print "%s: call to nf_conntrack_alloc %s bad test %s" % (p1[0].file,p1[0].line,p2[0].line) // </smpl> Signed-off-by: Julia Lawall <julia@diku.dk> Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-28Merge branch 'master' of ↵David S. Miller
git://git.kernel.org/pub/scm/linux/kernel/git/kaber/nf-next-2.6 Conflicts: net/netfilter/nf_conntrack_netlink.c
2008-11-26netfilter: ctnetlink: fix GFP_KERNEL allocation under spinlockPatrick McHardy
The previous fix for the conntrack creation race (netfilter: ctnetlink: fix conntrack creation race) missed a GFP_KERNEL allocation that is now performed while holding a spinlock. Switch to GFP_ATOMIC. Reported-and-tested-by: Zoltan Borbely <bozo@andrews.hu> Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-24netfilter: ctnetlink: fix conntrack creation racePatrick McHardy
Conntrack creation through ctnetlink has two races: - the timer may expire and free the conntrack concurrently, causing an invalid memory access when attempting to put it in the hash tables - an identical conntrack entry may be created in the packet processing path in the time between the lookup and hash insertion Hold the conntrack lock between the lookup and insertion to avoid this. Reported-by: Zoltan Borbely <bozo@andrews.hu> Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-18netfilter: ctnetlink: deliver events for conntracks changed from userspacePablo Neira Ayuso
As for now, the creation and update of conntracks via ctnetlink do not propagate an event to userspace. This can result in inconsistent situations if several userspace processes modify the connection tracking table by means of ctnetlink at the same time. Specifically, using the conntrack command line tool and conntrackd at the same time can trigger unconsistencies. This patch also modifies the event cache infrastructure to pass the process PID and the ECHO flag to nfnetlink_send() to report back to userspace if the process that triggered the change needs so. Based on a suggestion from Patrick McHardy. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Patrick McHardy <kaber@trash.net>
2008-11-18netfilter: ctnetlink: helper modules load-on-demand supportPablo Neira Ayuso
This patch adds module loading for helpers via ctnetlink. * Creation path: We support explicit and implicit helper assignation. For the explicit case, we try to load the module. If the module is correctly loaded and the helper is present, we return EAGAIN to re-start the creation. Otherwise, we return EOPNOTSUPP. * Update path: release the spin lock, load the module and check. If it is present, then return EAGAIN to re-start the update. This patch provides a refactorized function to lookup-and-set the connection tracking helper. The function removes the exported symbol __nf_ct_helper_find as it has not clients anymore. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Patrick McHardy <kaber@trash.net>