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2014-02-05netfilter: nf_conntrack: don't release a conntrack with non-zero refcntPablo Neira Ayuso1-6/+1
With this patch, the conntrack refcount is initially set to zero and it is bumped once it is added to any of the list, so we fulfill Eric's golden rule which is that all released objects always have a refcount that equals zero. Andrey Vagin reports that nf_conntrack_free can't be called for a conntrack with non-zero ref-counter, because it can race with nf_conntrack_find_get(). A conntrack slab is created with SLAB_DESTROY_BY_RCU. Non-zero ref-counter says that this conntrack is used. So when we release a conntrack with non-zero counter, we break this assumption. CPU1 CPU2 ____nf_conntrack_find() nf_ct_put() destroy_conntrack() ... init_conntrack __nf_conntrack_alloc (set use = 1) atomic_inc_not_zero(&ct->use) (use = 2) if (!l4proto->new(ct, skb, dataoff, timeouts)) nf_conntrack_free(ct); (use = 2 !!!) ... __nf_conntrack_alloc (set use = 1) if (!nf_ct_key_equal(h, tuple, zone)) nf_ct_put(ct); (use = 0) destroy_conntrack() /* continue to work with CT */ After applying the path "[PATCH] netfilter: nf_conntrack: fix RCU race in nf_conntrack_find_get" another bug was triggered in destroy_conntrack(): <4>[67096.759334] ------------[ cut here ]------------ <2>[67096.759353] kernel BUG at net/netfilter/nf_conntrack_core.c:211! ... <4>[67096.759837] Pid: 498649, comm: atdd veid: 666 Tainted: G C --------------- 2.6.32-042stab084.18 #1 042stab084_18 /DQ45CB <4>[67096.759932] RIP: 0010:[<ffffffffa03d99ac>] [<ffffffffa03d99ac>] destroy_conntrack+0x15c/0x190 [nf_conntrack] <4>[67096.760255] Call Trace: <4>[67096.760255] [<ffffffff814844a7>] nf_conntrack_destroy+0x17/0x30 <4>[67096.760255] [<ffffffffa03d9bb5>] nf_conntrack_find_get+0x85/0x130 [nf_conntrack] <4>[67096.760255] [<ffffffffa03d9fb2>] nf_conntrack_in+0x352/0xb60 [nf_conntrack] <4>[67096.760255] [<ffffffffa048c771>] ipv4_conntrack_local+0x51/0x60 [nf_conntrack_ipv4] <4>[67096.760255] [<ffffffff81484419>] nf_iterate+0x69/0xb0 <4>[67096.760255] [<ffffffff814b5b00>] ? dst_output+0x0/0x20 <4>[67096.760255] [<ffffffff814845d4>] nf_hook_slow+0x74/0x110 <4>[67096.760255] [<ffffffff814b5b00>] ? dst_output+0x0/0x20 <4>[67096.760255] [<ffffffff814b66d5>] raw_sendmsg+0x775/0x910 <4>[67096.760255] [<ffffffff8104c5a8>] ? flush_tlb_others_ipi+0x128/0x130 <4>[67096.760255] [<ffffffff8100bc4e>] ? apic_timer_interrupt+0xe/0x20 <4>[67096.760255] [<ffffffff8100bc4e>] ? apic_timer_interrupt+0xe/0x20 <4>[67096.760255] [<ffffffff814c136a>] inet_sendmsg+0x4a/0xb0 <4>[67096.760255] [<ffffffff81444e93>] ? sock_sendmsg+0x13/0x140 <4>[67096.760255] [<ffffffff81444f97>] sock_sendmsg+0x117/0x140 <4>[67096.760255] [<ffffffff8102e299>] ? native_smp_send_reschedule+0x49/0x60 <4>[67096.760255] [<ffffffff81519beb>] ? _spin_unlock_bh+0x1b/0x20 <4>[67096.760255] [<ffffffff8109d930>] ? autoremove_wake_function+0x0/0x40 <4>[67096.760255] [<ffffffff814960f0>] ? do_ip_setsockopt+0x90/0xd80 <4>[67096.760255] [<ffffffff8100bc4e>] ? apic_timer_interrupt+0xe/0x20 <4>[67096.760255] [<ffffffff8100bc4e>] ? apic_timer_interrupt+0xe/0x20 <4>[67096.760255] [<ffffffff814457c9>] sys_sendto+0x139/0x190 <4>[67096.760255] [<ffffffff810efa77>] ? audit_syscall_entry+0x1d7/0x200 <4>[67096.760255] [<ffffffff810ef7c5>] ? __audit_syscall_exit+0x265/0x290 <4>[67096.760255] [<ffffffff81474daf>] compat_sys_socketcall+0x13f/0x210 <4>[67096.760255] [<ffffffff8104dea3>] ia32_sysret+0x0/0x5 I have reused the original title for the RFC patch that Andrey posted and most of the original patch description. Cc: Eric Dumazet <edumazet@google.com> Cc: Andrew Vagin <avagin@parallels.com> Cc: Florian Westphal <fw@strlen.de> Reported-by: Andrew Vagin <avagin@parallels.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Reviewed-by: Eric Dumazet <edumazet@google.com> Acked-by: Andrew Vagin <avagin@parallels.com>
2014-01-03netfilter: xt_CT: fix error value in xt_ct_tg_check()Eric Leblond1-1/+3
If setting event mask fails then we were returning 0 for success. This patch updates return code to -EINVAL in case of problem. Signed-off-by: Eric Leblond <eric@regit.org> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2013-05-23netfilter: xt_CT: optimize XT_CT_NOTRACKEric Dumazet1-4/+6
The percpu untracked ct are not currently used for XT_CT_NOTRACK. xt_ct_tg_check()/xt_ct_target() provides a single ct. Thats not optimal as the ct->ct_general.use cache line will bounce among cpus. Use the intended [1] thing : xt_ct_target() should select the percpu object. [1] Refs : commit 5bfddbd46a95c97 ("netfilter: nf_conntrack: IPS_UNTRACKED bit") commit b3c5163fe0193a7 ("netfilter: nf_conntrack: per_cpu untracking") Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2013-02-05netfilter: xt_CT: add alias flagPablo Neira Ayuso1-3/+29
This patch adds the alias flag to support full NOTRACK target aliasing. Based on initial patch from Jozsef Kadlecsik. Acked-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hi> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2013-02-05netfilter: xt_CT: merge common code of revision 0 and 1Pablo Neira Ayuso1-89/+56
This patch merges the common code for revision 0 and 1. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2013-01-10netfilter: xt_CT: fix unset return value if conntrack zone are disabledPablo Neira Ayuso1-2/+2
net/netfilter/xt_CT.c: In function ‘xt_ct_tg_check_v1’: net/netfilter/xt_CT.c:250:6: warning: ‘ret’ may be used uninitialized in this function [-Wmaybe-uninitialized] net/netfilter/xt_CT.c: In function ‘xt_ct_tg_check_v0’: net/netfilter/xt_CT.c:112:6: warning: ‘ret’ may be used uninitialized in this function [-Wmaybe-uninitialized] Reported-by: Borislav Petkov <bp@alien8.de> Acked-by: Borislav Petkov <bp@alien8.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-12-24netfilter: xt_CT: recover NOTRACK target supportPablo Neira Ayuso1-1/+49
Florian Westphal reported that the removal of the NOTRACK target (9655050 netfilter: remove xt_NOTRACK) is breaking some existing setups. That removal was scheduled for removal since long time ago as described in Documentation/feature-removal-schedule.txt What: xt_NOTRACK Files: net/netfilter/xt_NOTRACK.c When: April 2011 Why: Superseded by xt_CT Still, people may have not notice / may have decided to stick to an old iptables version. I agree with him in that some more conservative approach by spotting some printk to warn users for some time is less agressive. Current iptables 1.4.16.3 already contains the aliasing support that makes it point to the CT target, so upgrading would fix it. Still, the policy so far has been to avoid pushing our users to upgrade. As a solution, this patch recovers the NOTRACK target inside the CT target and it now spots a warning. Reported-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-12-16netfilter: xt_CT: fix crash while destroy ct templatesPablo Neira Ayuso1-0/+8
In (d871bef netfilter: ctnetlink: dump entries from the dying and unconfirmed lists), we assume that all conntrack objects are inserted in any of the existing lists. However, template conntrack objects were not. This results in hitting BUG_ON in the destroy_conntrack path while removing a rule that uses the CT target. This patch fixes the situation by adding the template lists, which is where template conntrack objects reside now. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-10-15netfilter: xt_CT: fix timeout setting with IPv6Pablo Neira Ayuso1-4/+6
This patch fixes ip6tables and the CT target if it is used to set some custom conntrack timeout policy for IPv6. Use xt_ct_find_proto which already handles the ip6tables case for us. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-09-03netfilter: xt_CT: refactorize xt_ct_tg_checkPablo Neira Ayuso1-136/+126
This patch adds xt_ct_set_helper and xt_ct_set_timeout to reduce the size of xt_ct_tg_check. This aims to improve code mantainability by splitting xt_ct_tg_check in smaller chunks. Suggested by Eric Dumazet. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-06-16netfilter: nf_ct_helper: implement variable length helper private dataPablo Neira Ayuso1-18/+26
This patch uses the new variable length conntrack extensions. Instead of using union nf_conntrack_help that contain all the helper private data information, we allocate variable length area to store the private helper data. This patch includes the modification of all existing helpers. It also includes a couple of include header to avoid compilation warnings. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-05-17netfilter: xt_CT: remove redundant header includeEldad Zack1-1/+0
nf_conntrack_l4proto.h is included twice. Signed-off-by: Eldad Zack <eldad@fogrefinery.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-04-30netfilter: xt_CT: fix wrong checking in the timeout assignment pathPablo Neira Ayuso1-1/+1
The current checking always succeeded. We have to check the first character of the string to check that it's empty, thus, skipping the timeout path. This fixes the use of the CT target without the timeout option. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-04-03netfilter: xt_CT: fix missing put timeout object in error pathPablo Neira Ayuso1-5/+19
The error path misses putting the timeout object. This patch adds new function xt_ct_tg_timeout_put() to put the timeout object. Reported-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-04-03netfilter: xt_CT: allocation has to be GFP_ATOMIC under rcu_read_lock sectionPablo Neira Ayuso1-1/+1
Reported-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-04-03netfilter: xt_CT: remove a compile warningPablo Neira Ayuso1-0/+2
If CONFIG_NF_CONNTRACK_TIMEOUT=n we have following warning : CC [M] net/netfilter/xt_CT.o net/netfilter/xt_CT.c: In function ‘xt_ct_tg_check_v1’: net/netfilter/xt_CT.c:284: warning: label ‘err4’ defined but not used Reported-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-03-23netfilter: xt_CT: fix assignation of the generic protocol trackerPablo Neira Ayuso1-1/+8
`iptables -p all' uses 0 to match all protocols, while the conntrack subsystem uses 255. We still need `-p all' to attach the custom timeout policies for the generic protocol tracker. Moreover, we may use `iptables -p sctp' while the SCTP tracker is not loaded. In that case, we have to default on the generic protocol tracker. Another possibility is `iptables -p ip' that should be supported as well. This patch makes sure we validate all possible scenarios. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-03-23netfilter: xt_CT: missing rcu_read_lock section in timeout assignmentPablo Neira Ayuso1-6/+12
Fix a dereference to pointer without rcu_read_lock held. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-03-23netfilter: cttimeout: fix dependency with l4protocol conntrack modulePablo Neira Ayuso1-2/+4
This patch introduces nf_conntrack_l4proto_find_get() and nf_conntrack_l4proto_put() to fix module dependencies between timeout objects and l4-protocol conntrack modules. Thus, we make sure that the module cannot be removed if it is used by any of the cttimeout objects. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-03-07netfilter: xt_CT: allow to attach timeout policy + glue codePablo Neira Ayuso1-15/+205
This patch allows you to attach the timeout policy via the CT target, it adds a new revision of the target to ensure backward compatibility. Moreover, it also contains the glue code to stick the timeout object defined via nfnetlink_cttimeout to the given flow. Example usage (it requires installing the nfct tool and libnetfilter_cttimeout): 1) create the timeout policy: nfct timeout add tcp-policy0 inet tcp \ established 1000 close 10 time_wait 10 last_ack 10 2) attach the timeout policy to the packet: iptables -I PREROUTING -t raw -p tcp -j CT --timeout tcp-policy0 You have to install the following user-space software: a) libnetfilter_cttimeout: git://git.netfilter.org/libnetfilter_cttimeout b) nfct: git://git.netfilter.org/nfct You also have to get iptables with -j CT --timeout support. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-01-16netfilter: revert user-space expectation helper supportPablo Neira Ayuso1-5/+3
This patch partially reverts: 3d058d7 netfilter: rework user-space expectation helper support that was applied during the 3.2 development cycle. After this patch, the tree remains just like before patch bc01bef, that initially added the preliminary infrastructure. I decided to partially revert this patch because the approach that I proposed to resolve this problem is broken in NAT setups. Moreover, a new infrastructure will be submitted for the 3.3.x development cycle that resolve the existing issues while providing a neat solution. Since nobody has been seriously using this infrastructure in user-space, the removal of this feature should affect any know FOSS project (to my knowledge). Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2011-12-23netfilter: rework user-space expectation helper supportPablo Neira Ayuso1-3/+5
This partially reworks bc01befdcf3e40979eb518085a075cbf0aacede0 which added userspace expectation support. This patch removes the nf_ct_userspace_expect_list since now we force to use the new iptables CT target feature to add the helper extension for conntracks that have attached expectations from userspace. A new version of the proof-of-concept code to implement userspace helpers from userspace is available at: http://people.netfilter.org/pablo/userspace-conntrack-helpers/nf-ftp-helper-POC.tar.bz2 This patch also modifies the CT target to allow to set the conntrack's userspace helper status flags. This flag is used to tell the conntrack system to explicitly allocate the helper extension. This helper extension is useful to link the userspace expectations with the master conntrack that is being tracked from one userspace helper. This feature fixes a problem in the current approach of the userspace helper support. Basically, if the master conntrack that has got a userspace expectation vanishes, the expectations point to one invalid memory address. Thus, triggering an oops in the expectation deletion event path. I decided not to add a new revision of the CT target because I only needed to add a new flag for it. I'll document in this issue in the iptables manpage. I have also changed the return value from EINVAL to EOPNOTSUPP if one flag not supported is specified. Thus, in the future adding new features that only require a new flag can be added without a new revision. There is no official code using this in userspace (apart from the proof-of-concept) that uses this infrastructure but there will be some by beginning 2012. Reported-by: Sam Roberts <vieuxtech@gmail.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2011-04-21netfilter: xt_CT: provide info on why a rule was rejectedJan Engelhardt1-3/+8
Signed-off-by: Jan Engelhardt <jengelh@medozas.de> Signed-off-by: Patrick McHardy <kaber@trash.net>
2010-10-21secmark: make secmark object handling genericEric Paris1-1/+0
Right now secmark has lots of direct selinux calls. Use all LSM calls and remove all SELinux specific knowledge. The only SELinux specific knowledge we leave is the mode. The only point is to make sure that other LSMs at least test this generic code before they assume it works. (They may also have to make changes if they do not represent labels as strings) Signed-off-by: Eric Paris <eparis@redhat.com> Acked-by: Paul Moore <paul.moore@hp.com> Acked-by: Patrick McHardy <kaber@trash.net> Signed-off-by: James Morris <jmorris@namei.org>
2010-06-08netfilter: nf_conntrack: IPS_UNTRACKED bitEric Dumazet1-2/+2
NOTRACK makes all cpus share a cache line on nf_conntrack_untracked twice per packet. This is bad for performance. __read_mostly annotation is also a bad choice. This patch introduces IPS_UNTRACKED bit so that we can use later a per_cpu untrack structure more easily. A new helper, nf_ct_untracked_get() returns a pointer to nf_conntrack_untracked. Another one, nf_ct_untracked_status_or() is used by nf_nat_init() to add IPS_NAT_DONE_MASK bits to untracked status. nf_ct_is_untracked() prototype is changed to work on a nf_conn pointer. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: Patrick McHardy <kaber@trash.net>
2010-05-11netfilter: xtables: substitute temporary defines by final nameJan Engelhardt1-1/+1
Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
2010-04-20Merge branch 'master' of /repos/git/net-next-2.6Patrick McHardy1-0/+1
Conflicts: Documentation/feature-removal-schedule.txt net/ipv6/netfilter/ip6t_REJECT.c net/netfilter/xt_limit.c Signed-off-by: Patrick McHardy <kaber@trash.net>
2010-03-30include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.hTejun Heo1-0/+1
percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-25netfilter: xtables: slightly better error reportingJan Engelhardt1-2/+9
When extended status codes are available, such as ENOMEM on failed allocations, or subsequent functions (e.g. nf_ct_get_l3proto), passing them up to userspace seems like a good idea compared to just always EINVAL. Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
2010-03-25netfilter: xtables: change targets to return error codeJan Engelhardt1-3/+3
Part of the transition of done by this semantic patch: // <smpl> @ rule1 @ struct xt_target ops; identifier check; @@ ops.checkentry = check; @@ identifier rule1.check; @@ check(...) { <... -return true; +return 0; ...> } @@ identifier rule1.check; @@ check(...) { <... -return false; +return -EINVAL; ...> } // </smpl> Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
2010-03-25netfilter: xtables: change xt_target.checkentry return typeJan Engelhardt1-1/+1
Restore function signatures from bool to int so that we can report memory allocation failures or similar using -ENOMEM rather than always having to pass -EINVAL back. // <smpl> @@ type bool; identifier check, par; @@ -bool check +int check (struct xt_tgchk_param *par) { ... } // </smpl> Minus the change it does to xt_ct_find_proto. Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
2010-03-18netfilter: xtables: do without explicit XT_ALIGNJan Engelhardt1-1/+1
XT_ALIGN is already applied on matchsize/targetsize in x_tables.c, so it is not strictly needed in the extensions. Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
2010-03-17netfilter: xt_CT: par->family is an nfprotoJan Engelhardt1-2/+2
Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
2010-02-15netfilter: nf_conntrack: add support for "conntrack zones"Patrick McHardy1-1/+7
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>
2010-02-03netfilter: xtables: add CT targetPatrick McHardy1-0/+158
Add a new target for the raw table, which can be used to specify conntrack parameters for specific connections, f.i. the conntrack helper. The target attaches a "template" connection tracking entry to the skb, which is used by the conntrack core when initializing a new conntrack. Signed-off-by: Patrick McHardy <kaber@trash.net>