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>
This patch removes the module dependency between ctnetlink and
nf_nat by means of an indirect call that is initialized when
nf_nat is loaded. Now, nf_conntrack_netlink only requires
nf_conntrack and nfnetlink.
This patch puts nfnetlink_parse_nat_setup_hook into the
nf_conntrack_core to avoid dependencies between ctnetlink,
nf_conntrack_ipv4 and nf_conntrack_ipv6.
This patch also introduces the function ctnetlink_change_nat
that is only invoked from the creation path. Actually, the
nat handling cannot be invoked from the update path since
this is not allowed. By introducing this function, we remove
the useless nat handling in the update path and we avoid
deadlock-prone code.
This patch also adds the required EAGAIN logic for nfnetlink.
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>
Add init_net checks to not remove kmem_caches twice and so on.
Refactor functions to split code which should be executed only for
init_net into one place.
ip_ct_attach and ip_ct_destroy assignments remain separate, because
they're separate stages in setup and teardown.
NOTE: NOTRACK code is in for-every-net part. It will be made per-netns
after we decidce how to do it correctly.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Heh, last minute proof-reading of this patch made me think,
that this is actually unneeded, simply because "ct" pointers will be
different for different conntracks in different netns, just like they
are different in one netns.
Not so sure anymore.
[Patrick: pointers will be different, flushing can only be done while
inactive though and thus it needs to be per netns]
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
This is cleaner, we already know conntrack to which event is relevant.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Again, it's deducible from skb, but we're going to use it for
nf_conntrack_checksum and statistics, so just pass it from upper layer.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
It's deducible from skb->dev or skb->dst->dev, but we know netns at
the moment of call, so pass it down and use for finding and creating
conntracks.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
What is confirmed connection in one netns can very well be unconfirmed
in another one.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Make per-netns a) expectation hash and b) expectations count.
Expectations always belongs to netns to which it's master conntrack belong.
This is natural and doesn't bloat expectation.
Proc files and leaf users are stubbed to init_net, this is temporary.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
* make per-netns conntrack hash
Other solution is to add ->ct_net pointer to tuplehashes and still has one
hash, I tried that it's ugly and requires more code deep down in protocol
modules et al.
* propagate netns pointer to where needed, e. g. to conntrack iterators.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Sysctls and proc files are stubbed to init_net's one. This is temporary.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Conntrack (struct nf_conn) gets pointer to netns: ->ct_net -- netns in which
it was created. It comes from netdevice.
->ct_net is write-once field.
Every conntrack in system has ->ct_net initialized, no exceptions.
->ct_net doesn't pin netns: conntracks are recycled after timeouts and
pinning background traffic will prevent netns from even starting shutdown
sequence.
Right now every conntrack is created in init_net.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
One comment: #ifdefs around #include is necessary to overcome amazing compile
breakages in NOTRACK-in-netns patch (see below).
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
and (try to) consistently use u_int8_t for the L3 family.
Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Starting with 9043476f72 ("[PATCH]
sanitize proc_sysctl") we have two netfilter releated problems:
- WARNING: at kernel/sysctl.c:1966 unregister_sysctl_table+0xcc/0x103(),
caused by wrong order of ini/fini calls
- net.netfilter is duplicated and has truncated set of records
Thanks to very useful guidelines from Al Viro, this patch fixes both
of them.
Signed-off-by: Krzysztof Piotr Oledzki <ole@ans.pl>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
Initially netfilter has had 64bit counters for conntrack-based accounting, but
it was changed in 2.6.14 to save memory. Unfortunately in-kernel 64bit counters are
still required, for example for "connbytes" extension. However, 64bit counters
waste a lot of memory and it was not possible to enable/disable it runtime.
This patch:
- reimplements accounting with respect to the extension infrastructure,
- makes one global version of seq_print_acct() instead of two seq_print_counters(),
- makes it possible to enable it at boot time (for CONFIG_SYSCTL/CONFIG_SYSFS=n),
- makes it possible to enable/disable it at runtime by sysctl or sysfs,
- extends counters from 32bit to 64bit,
- renames ip_conntrack_counter -> nf_conn_counter,
- enables accounting code unconditionally (no longer depends on CONFIG_NF_CT_ACCT),
- set initial accounting enable state based on CONFIG_NF_CT_ACCT
- removes buggy IPCT_COUNTER_FILLING event handling.
If accounting is enabled newly created connections get additional acct extend.
Old connections are not changed as it is not possible to add a ct_extend area
to confirmed conntrack. Accounting is performed for all connections with
acct extend regardless of a current state of "net.netfilter.nf_conntrack_acct".
Signed-off-by: Krzysztof Piotr Oledzki <ole@ans.pl>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
ctnetlink does not need to allocate the conntrack entries with GFP_ATOMIC
as its code is executed in user context.
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>
When creation of a new conntrack entry in ctnetlink fails after having
set up the NAT mappings, the conntrack has an extension area allocated
that is not getting properly destroyed when freeing the conntrack again.
This means the NAT extension is still in the bysource hash, causing a
crash when walking over the hash chain the next time:
BUG: unable to handle kernel paging request at 00120fbd
IP: [<c03d394b>] nf_nat_setup_info+0x221/0x58a
*pde = 00000000
Oops: 0000 [#1] PREEMPT SMP
Pid: 2795, comm: conntrackd Not tainted (2.6.26-rc5 #1)
EIP: 0060:[<c03d394b>] EFLAGS: 00010206 CPU: 1
EIP is at nf_nat_setup_info+0x221/0x58a
EAX: 00120fbd EBX: 00120fbd ECX: 00000001 EDX: 00000000
ESI: 0000019e EDI: e853bbb4 EBP: e853bbc8 ESP: e853bb78
DS: 007b ES: 007b FS: 00d8 GS: 0033 SS: 0068
Process conntrackd (pid: 2795, ti=e853a000 task=f7de10f0 task.ti=e853a000)
Stack: 00000000 e853bc2c e85672ec 00000008 c0561084 63c1db4a 00000000 00000000
00000000 0002e109 61d2b1c3 00000000 00000000 00000000 01114e22 61d2b1c3
00000000 00000000 f7444674 e853bc04 00000008 c038e728 0000000a f7444674
Call Trace:
[<c038e728>] nla_parse+0x5c/0xb0
[<c0397c1b>] ctnetlink_change_status+0x190/0x1c6
[<c0397eec>] ctnetlink_new_conntrack+0x189/0x61f
[<c0119aee>] update_curr+0x3d/0x52
[<c03902d1>] nfnetlink_rcv_msg+0xc1/0xd8
[<c0390228>] nfnetlink_rcv_msg+0x18/0xd8
[<c0390210>] nfnetlink_rcv_msg+0x0/0xd8
[<c038d2ce>] netlink_rcv_skb+0x2d/0x71
[<c0390205>] nfnetlink_rcv+0x19/0x24
[<c038d0f5>] netlink_unicast+0x1b3/0x216
...
Move invocation of the extension destructors to nf_conntrack_free()
to fix this problem.
Fixes http://bugzilla.kernel.org/show_bug.cgi?id=10875
Reported-and-Tested-by: Krzysztof Piotr Oledzki <ole@ans.pl>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently the last packet of a connection isn't accounted when its causing
abnormal termination.
Introduces nf_ct_kill_acct() which increments the accounting counters on
conntrack kill. The new function was necessary, because there are calls
to nf_ct_kill() which don't need accounting:
nf_conntrack_proto_tcp.c line ~847:
Kills ct and returns NF_REPEAT. We don't want to count twice.
nf_conntrack_proto_tcp.c line ~880:
Kills ct and returns NF_DROP. I think we don't want to count dropped
packets.
nf_conntrack_netlink.c line ~824:
As far as I can see ctnetlink_del_conntrack() is used to destroy a
conntrack on behalf of the user. There is an sk_buff, but I don't think
this is an actual packet. Incrementing counters here is therefore not
desired.
Signed-off-by: Fabian Hugelshofer <hugelshofer2006@gmx.ch>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Encapsulate the common
if (del_timer(&ct->timeout))
ct->timeout.function((unsigned long)ct)
sequence in a new function.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
commit 0794935e "[NETFILTER]: nf_conntrack: optimize hash_conntrack()"
results in ARM platforms hashing uninitialised padding. This padding
doesn't exist on other architectures.
Fix this by replacing NF_CT_TUPLE_U_BLANK() with memset() to ensure
everything is initialised. There were only 4 bytes that
NF_CT_TUPLE_U_BLANK() wasn't clearing anyway (or 12 bytes on ARM).
Signed-off-by: Philip Craig <philipc@snapgear.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Directly call IPv4 and IPv6 variants where the address family is
easily known.
Signed-off-by: Jan Engelhardt <jengelh@computergmbh.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Since we're using RCU for the conntrack hash now, we need to avoid
getting preempted or interrupted by BHs while changing the stats.
Fixes warning reported by Tilman Schmidt <tilman@imap.cc> when using
preemptible RCU:
[ 48.180297] BUG: using smp_processor_id() in preemptible [00000000] code: ntpdate/3562
[ 48.180297] caller is __nf_conntrack_find+0x9b/0xeb [nf_conntrack]
[ 48.180297] Pid: 3562, comm: ntpdate Not tainted 2.6.25-rc2-mm1-testing #1
[ 48.180297] [<c02015b9>] debug_smp_processor_id+0x99/0xb0
[ 48.180297] [<fac643a7>] __nf_conntrack_find+0x9b/0xeb [nf_conntrack]
Tested-by: Tilman Schmidt <tilman@imap.cc>
Tested-by: Christian Casteyde <casteyde.christian@free.fr> [Bugzilla #10097]
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Rename all "conntrack" variables to "ct" for more consistency and
avoiding some overly long lines.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
early_drop() is only called *very* rarely, unfortunately gcc inlines it
into the hotpath because there is only a single caller. Explicitly mark
it noinline.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Avoid calling jhash three times and hash the entire tuple in one go.
__hash_conntrack | -485 # 760 -> 275, # inlines: 3 -> 1, size inlines: 717 -> 252
1 function changed, 485 bytes removed
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Ignoring specific entries in __nf_conntrack_find() is only needed by NAT
for nf_conntrack_tuple_taken(). Remove it from __nf_conntrack_find()
and make nf_conntrack_tuple_taken() search the hash itself.
Saves 54 bytes of text in the hotpath on x86_64:
__nf_conntrack_find | -54 # 321 -> 267, # inlines: 3 -> 2, size inlines: 181 -> 127
nf_conntrack_tuple_taken | +305 # 15 -> 320, lexblocks: 0 -> 3, # inlines: 0 -> 3, size inlines: 0 -> 181
nf_conntrack_find_get | -2 # 90 -> 88
3 functions changed, 305 bytes added, 56 bytes removed, diff: +249
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
With the RCU conversion only write_lock usages of nf_conntrack_lock are
left (except one read_lock that should actually use write_lock in the
H.323 helper). Switch to a spinlock.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
The conntrack is unconfirmed, so we have an exclusive reference, which
means that the write_lock is definitely unneeded. A read_lock used to
be needed for the helper lookup, but since we're using RCU for helpers
now rcu_read_lock is enough.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Don't skip accounting for conntracks with the FIXED_TIMEOUT bit.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
The hashtable size is really unsigned so sparse complains when you pass
a signed integer. Change all uses to make it consistent.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
- Remove declarations of non-existing variables and functions
- Move helper init/cleanup function declarations to nf_conntrack_helper.h
- Remove unneeded __nf_conntrack_attach declaration and make it static
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Apply Eric Dumazet's jhash optimizations where applicable. Quoting Eric:
Thanks to jhash, hash value uses full 32 bits. Instead of returning
hash % size (implying a divide) we return the high 32 bits of the
(hash * size) that will give results between [0 and size-1] and same
hash distribution.
On most cpus, a multiply is less expensive than a divide, by an order
of magnitude.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Some users do "modprobe ip_conntrack hashsize=...". Since we have the
module aliases this loads nf_conntrack_ipv4 and nf_conntrack, the
hashsize parameter is unknown for nf_conntrack_ipv4 however and makes
it fail.
Allow to specify hashsize= for both nf_conntrack and nf_conntrack_ipv4.
Note: the nf_conntrack message in the ringbuffer will display an
incorrect hashsize since nf_conntrack is first pulled in as a
dependency and calculates the size itself, then it gets changed
through a call to nf_conntrack_set_hashsize().
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
This allocation is expected to fail and we handle it by fallback to vmalloc().
So don't scare people with nasty messages like
http://bugzilla.kernel.org/show_bug.cgi?id=9190
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
With all the users of the double pointers removed, this patch mops up by
finally replacing all occurances of sk_buff ** in the netfilter API by
sk_buff *.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Remove the per-conntrack ID, its not necessary anymore for dumping.
For compatiblity reasons we send the address of the conntrack to
userspace as ID.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
There is no struct nfattr anymore, rename functions to 'nlattr'.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Patrick McHardy