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>
The message "nf_log_packet: can't log since no backend logging module loaded
in! Please either load one, or disable logging explicitly" was displayed for
each logged packet when no userspace application is listening to nflog events.
The message seems to warn for a problem with a kernel module missing but as
said before this is not the case. I thus propose to suppress the message (I
don't see any reason to flood the log because a user application has crashed.)
Signed-off-by: Eric Leblond <eric@inl.fr>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
- No need to perform data_len = 0 in the switch command, since data_len
is initialized to 0 in the beginning of the ipq_build_packet_message()
method.
- {ip,ip6}_queue: We can reach nlmsg_failure only from one place; skb is
sure to be NULL when getting there; since skb is NULL, there is no need
to check this fact and call kfree_skb().
Signed-off-by: Rami Rosen <ramirose@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
When a conntrack is destroyed, the connection status does not get
exported to netlink. I don't see a reason for not doing so. This patch
exports the status on all conntrack events.
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>
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>
The ksize() API is going away because it is being abused and it doesn't even
work consistenly across different allocators. Therefore, convert
net/netfilter/nf_conntrack_extend.c to use krealloc().
Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
The following patch implements a new "security" table for iptables, so
that MAC (SELinux etc.) networking rules can be managed separately to
standard DAC rules.
This is to help with distro integration of the new secmark-based
network controls, per various previous discussions.
The need for a separate table arises from the fact that existing tools
and usage of iptables will likely clash with centralized MAC policy
management.
The SECMARK and CONNSECMARK targets will still be valid in the mangle
table to prevent breakage of existing users.
Signed-off-by: James Morris <jmorris@namei.org>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds full support for SCTP to ctnetlink. This includes three
new attributes: state, original vtag and reply vtag.
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>
This patch groups ctnetlink errors into three logical sets:
* Malformed messages: if ctnetlink receives a message without some mandatory
attribute, then it returns EINVAL.
* Unsupported operations: if userspace tries to perform an unsupported
operation, then it returns EOPNOTSUPP.
* Unchangeable: if userspace tries to change some attribute of the
conntrack object that can only be set once, then it returns EBUSY.
This patch reduces the number of -EINVAL from 23 to 14 and it results in
5 -EBUSY and 6 -EOPNOTSUPP.
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>
In xt_connlimit match module, the counter of an IP is decreased when
the TCP packet is go through the chain with ip_conntrack state TW.
Well, it's very natural that the server and client close the socket
with FIN packet. But when the client/server close the socket with RST
packet(using so_linger), the counter for this connection still exsit.
The following patch can fix it which is based on linux-2.6.25.4
Signed-off-by: Dong Wei <dwei.zh@gmail.com>
Acked-by: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Alexey Dobriyan <adobriyan@parallels.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (73 commits)
net: Fix typo in net/core/sock.c.
ppp: Do not free not yet unregistered net device.
netfilter: xt_iprange: module aliases for xt_iprange
netfilter: ctnetlink: dump conntrack ID in event messages
irda: Fix a misalign access issue. (v2)
sctp: Fix use of uninitialized pointer
cipso: Relax too much careful cipso hash function.
tcp FRTO: work-around inorder receivers
tcp FRTO: Fix fallback to conventional recovery
New maintainer for Intel ethernet adapters
DM9000: Use delayed work to update MII PHY state
DM9000: Update and fix driver debugging messages
DM9000: Add __devinit and __devexit attributes to probe and remove
sky2: fix simple define thinko
[netdrvr] sfc: sfc: Add self-test support
[netdrvr] sfc: Increment rx_reset when reported as driver event
[netdrvr] sfc: Remove unused macro EFX_XAUI_RETRAIN_MAX
[netdrvr] sfc: Fix code formatting
[netdrvr] sfc: Remove kernel-doc comments for removed members of struct efx_nic
[netdrvr] sfc: Remove garbage from comment
...
Using iptables 1.3.8 with kernel 2.6.25, rules which include '-m
iprange' don't automatically pull in xt_iprange module. Below patch
adds module aliases to fix that. Patch against latest -git, but seems
like a good candidate for -stable also.
Signed-off-by: Phil Oester <kernel@linuxace.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Conntrack ID is not put (anymore ?) in event messages. This causes
current ulogd2 code to fail because it uses the ID to build a hash in
userspace. This hash is used to be able to output the starting time of
a connection.
Conntrack ID can be used in userspace application to maintain an easy
match between kernel connections list and userspace one. It may worth
to add it if there is no performance related issue.
[ Patrick: it was never included in events, but really should be ]
Signed-off-by: Eric Leblond <eric@inl.fr>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (32 commits)
net: Added ASSERT_RTNL() to dev_open() and dev_close().
can: Fix can_send() handling on dev_queue_xmit() failures
netns: Fix arbitrary net_device-s corruptions on net_ns stop.
netfilter: Kconfig: default DCCP/SCTP conntrack support to the protocol config values
netfilter: nf_conntrack_sip: restrict RTP expect flushing on error to last request
macvlan: Fix memleak on device removal/crash on module removal
net/ipv4: correct RFC 1122 section reference in comment
tcp FRTO: SACK variant is errorneously used with NewReno
e1000e: don't return half-read eeprom on error
ucc_geth: Don't use RX clock as TX clock.
cxgb3: Use CAP_SYS_RAWIO for firmware
pcnet32: delete non NAPI code from driver.
fs_enet: Fix a memory leak in fs_enet_mdio_probe
[netdrvr] eexpress: IPv6 fails - multicast problems
3c59x: use netstats in net_device structure
3c980-TX needs EXTRA_PREAMBLE
fix warning in drivers/net/appletalk/cops.c
e1000e: Add support for BM PHYs on ICH9
uli526x: fix endianness issues in the setup frame
uli526x: initialize the hardware prior to requesting interrupts
...
When conntrack and DCCP/SCTP protocols are enabled, chances are good
that people also want DCCP/SCTP conntrack and NAT support.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Some Inovaphone PBXs exhibit very stange behaviour: when dialing for
example "123", the device sends INVITE requests for "1", "12" and
"123" back to back. The first requests will elicit error responses
from the receiver, causing the SIP helper to flush the RTP
expectations even though we might still see a positive response.
Note the sequence number of the last INVITE request that contained a
media description and only flush the expectations when receiving a
negative response for that sequence number.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (47 commits)
rose: Wrong list_lock argument in rose_node seqops
netns: Fix reassembly timer to use the right namespace
netns: Fix device renaming for sysfs
bnx2: Update version to 1.7.5.
bnx2: Update RV2P firmware for 5709.
bnx2: Zero out context memory for 5709.
bnx2: Fix register test on 5709.
bnx2: Fix remote PHY initial link state.
bnx2: Refine remote PHY locking.
bridge: forwarding table information for >256 devices
tg3: Update version to 3.92
tg3: Add link state reporting to UMP firmware
tg3: Fix ethtool loopback test for 5761 BX devices
tg3: Fix 5761 NVRAM sizes
tg3: Use constant 500KHz MI clock on adapters with a CPMU
hci_usb.h: fix hard-to-trigger race
dccp: ccid2.c, ccid3.c use clamp(), clamp_t()
net: remove NR_CPUS arrays in net/core/dev.c
net: use get/put_unaligned_* helpers
bluetooth: use get/put_unaligned_* helpers
...
Replace proc_net_fops_create with proc_create_data.
Signed-off-by: Denis V. Lunev <den@openvz.org>
Acked-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Replace create_proc_entry with specially created for this purpose proc_create.
Signed-off-by: Denis V. Lunev <den@openvz.org>
Acked-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Simply replace proc_create and further data assigned with proc_create_data.
Signed-off-by: Denis V. Lunev <den@openvz.org>
Acked-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Rename div64_64 to div64_u64 to make it consistent with the other divide
functions, so it clearly includes the type of the divide. Move its definition
to math64.h as currently no architecture overrides the generic implementation.
They can still override it of course, but the duplicated declarations are
avoided.
Signed-off-by: Roman Zippel <zippel@linux-m68k.org>
Cc: Avi Kivity <avi@qumranet.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Patrick McHardy <kaber@trash.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (53 commits)
tcp: Overflow bug in Vegas
[IPv4] UFO: prevent generation of chained skb destined to UFO device
iwlwifi: move the selects to the tristate drivers
ipv4: annotate a few functions __init in ipconfig.c
atm: ambassador: vcc_sf semaphore to mutex
MAINTAINERS: The socketcan-core list is subscribers-only.
netfilter: nf_conntrack: padding breaks conntrack hash on ARM
ipv4: Update MTU to all related cache entries in ip_rt_frag_needed()
sch_sfq: use del_timer_sync() in sfq_destroy()
net: Add compat support for getsockopt (MCAST_MSFILTER)
net: Several cleanups for the setsockopt compat support.
ipvs: fix oops in backup for fwmark conn templates
bridge: kernel panic when unloading bridge module
bridge: fix error handling in br_add_if()
netfilter: {nfnetlink,ip,ip6}_queue: fix skb_over_panic when enlarging packets
netfilter: x_tables: fix net namespace leak when reading /proc/net/xxx_tables_names
netfilter: xt_TCPOPTSTRIP: signed tcphoff for ipv6_skip_exthdr() retval
tcp: Limit cwnd growth when deferring for GSO
tcp: Allow send-limited cwnd to grow up to max_burst when gso disabled
[netdrvr] gianfar: Determine TBIPA value dynamically
...
Some drivers have duplicated unlikely() macros. IS_ERR() already has
unlikely() in itself.
This patch cleans up such pointless code.
Signed-off-by: Hirofumi Nakagawa <hnakagawa@miraclelinux.com>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Jeff Garzik <jeff@garzik.org>
Cc: Paul Clements <paul.clements@steeleye.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: David Brownell <david-b@pacbell.net>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Michael Halcrow <mhalcrow@us.ibm.com>
Cc: Anton Altaparmakov <aia21@cantab.net>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Carsten Otte <cotte@de.ibm.com>
Cc: Patrick McHardy <kaber@trash.net>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Jaroslav Kysela <perex@perex.cz>
Cc: Takashi Iwai <tiwai@suse.de>
Acked-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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>
While reinjecting *bigger* modified versions of IPv6 packets using
libnetfilter_queue, things work fine on a 2.6.24 kernel (2.6.22 too)
but I get the following on recents kernels (2.6.25, trace below is
against today's net-2.6 git tree):
skb_over_panic: text:c04fddb0 len:696 put:632 head:f7592c00 data:f7592c00 tail:0xf7592eb8 end:0xf7592e80 dev:eth0
------------[ cut here ]------------
invalid opcode: 0000 [#1] PREEMPT
Process sendd (pid: 3657, ti=f6014000 task=f77c31d0 task.ti=f6014000)
Stack: c071e638 c04fddb0 000002b8 00000278 f7592c00 f7592c00 f7592eb8 f7592e80
f763c000 f6bc5200 f7592c40 f6015c34 c04cdbfc f6bc5200 00000278 f6015c60
c04fddb0 00000020 f72a10c0 f751b420 00000001 0000000a 000002b8 c065582c
Call Trace:
[<c04fddb0>] ? nfqnl_recv_verdict+0x1c0/0x2e0
[<c04cdbfc>] ? skb_put+0x3c/0x40
[<c04fddb0>] ? nfqnl_recv_verdict+0x1c0/0x2e0
[<c04fd115>] ? nfnetlink_rcv_msg+0xf5/0x160
[<c04fd03e>] ? nfnetlink_rcv_msg+0x1e/0x160
[<c04fd020>] ? nfnetlink_rcv_msg+0x0/0x160
[<c04f8ed7>] ? netlink_rcv_skb+0x77/0xa0
[<c04fcefc>] ? nfnetlink_rcv+0x1c/0x30
[<c04f8c73>] ? netlink_unicast+0x243/0x2b0
[<c04cfaba>] ? memcpy_fromiovec+0x4a/0x70
[<c04f9406>] ? netlink_sendmsg+0x1c6/0x270
[<c04c8244>] ? sock_sendmsg+0xc4/0xf0
[<c011970d>] ? set_next_entity+0x1d/0x50
[<c0133a80>] ? autoremove_wake_function+0x0/0x40
[<c0118f9e>] ? __wake_up_common+0x3e/0x70
[<c0342fbf>] ? n_tty_receive_buf+0x34f/0x1280
[<c011d308>] ? __wake_up+0x68/0x70
[<c02cea47>] ? copy_from_user+0x37/0x70
[<c04cfd7c>] ? verify_iovec+0x2c/0x90
[<c04c837a>] ? sys_sendmsg+0x10a/0x230
[<c011967a>] ? __dequeue_entity+0x2a/0xa0
[<c011970d>] ? set_next_entity+0x1d/0x50
[<c0345397>] ? pty_write+0x47/0x60
[<c033d59b>] ? tty_default_put_char+0x1b/0x20
[<c011d2e9>] ? __wake_up+0x49/0x70
[<c033df99>] ? tty_ldisc_deref+0x39/0x90
[<c033ff20>] ? tty_write+0x1a0/0x1b0
[<c04c93af>] ? sys_socketcall+0x7f/0x260
[<c0102ff9>] ? sysenter_past_esp+0x6a/0x91
[<c05f0000>] ? snd_intel8x0m_probe+0x270/0x6e0
=======================
Code: 00 00 89 5c 24 14 8b 98 9c 00 00 00 89 54 24 0c 89 5c 24 10 8b 40 50 89 4c 24 04 c7 04 24 38 e6 71 c0 89 44 24 08 e8 c4 46 c5 ff <0f> 0b eb fe 55 89 e5 56 89 d6 53 89 c3 83 ec 0c 8b 40 50 39 d0
EIP: [<c04ccdfc>] skb_over_panic+0x5c/0x60 SS:ESP 0068:f6015bf8
Looking at the code, I ended up in nfq_mangle() function (called by
nfqnl_recv_verdict()) which performs a call to skb_copy_expand() due to
the increased size of data passed to the function. AFAICT, it should ask
for 'diff' instead of 'diff - skb_tailroom(e->skb)'. Because the
resulting sk_buff has not enough space to support the skb_put(skb, diff)
call a few lines later, this results in the call to skb_over_panic().
The patch below asks for allocation of a copy with enough space for
mangled packet and the same amount of headroom as old sk_buff. While
looking at how the regression appeared (e2b58a67), I noticed the same
pattern in ipq_mangle_ipv6() and ipq_mangle_ipv4(). The patch corrects
those locations too.
Tested with bigger reinjected IPv6 packets (nfqnl_mangle() path), things
are ok (2.6.25 and today's net-2.6 git tree).
Signed-off-by: Arnaud Ebalard <arno@natisbad.org>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
The seq_open_net() call should be accompanied with seq_release_net() one.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
if tcphoff remains unsigned, a negative ipv6_skip_exthdr() return value will
go unnoticed,
Signed-off-by: Roel Kluin <12o3l@tiscali.nl>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Reported by Ingo Molnar.
The SIP helper is also useful without NAT. This patch adds an ifdef
around the RTP call optimization for NATed clients.
Signed-off-by: Patrick McHardy <kaber@trash.net>
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>
Invalid states can cause out-of-bound memory accesses of the state table.
Also don't insist on having a new state contained in the netlink message.
Signed-off-by: Patrick McHardy <kaber@trash.net>
New extensions may only be added to unconfirmed conntracks to avoid races
when reallocating the storage.
Also change NF_CT_ASSERT to use WARN_ON to get backtraces.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Move the UDP-Lite conntrack checksum validation to a generic helper
similar to nf_checksum() and make it fall back to nf_checksum()
in case the full packet is to be checksummed and hardware checksums
are available. This is to be used by DCCP conntrack, which also
needs to verify partial checksums.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Move responsibility for setting the IP_NAT_RANGE_PROTO_SPECIFIED flag
to the NAT protocol, properly propagate errors and get rid of ugly
return value convention.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Some callers pass uninitialized structures, clear the address to make
sure later comparisions work properly.
Signed-off-by: Patrick McHardy <kaber@trash.net>