As soon as rcu_read_unlock() is called, there is no guarantee current
thread can safely derefence t pointer, rcu protected.
Fix is to copy t->alloc_size in a temporary variable.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
I initially noticed this because of the compiler warning below, but it
does seem to be a valid concern in the case where ct_sip_get_header()
returns 0 in the first iteration of the while loop.
net/netfilter/nf_conntrack_sip.c: In function 'sip_help_tcp':
net/netfilter/nf_conntrack_sip.c:1379: warning: 'ret' may be used uninitialized in this function
Signed-off-by: Simon Horman <horms@verge.net.au>
[Patrick: changed NF_DROP to NF_ACCEPT]
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
transparent field of a socket is either inet_twsk(sk)->tw_transparent
for timewait sockets, or inet_sk(sk)->transparent for other sockets
(TCP/UDP).
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
- Do not create expectation when forwarding the PORT
command to avoid blocking the connection. The problem is that
nf_conntrack_ftp.c:help() tries to create the same expectation later in
POST_ROUTING and drops the packet with "dropping packet" message after
failure in nf_ct_expect_related.
- Change ip_vs_update_conntrack to alter the conntrack
for related connections from real server. If we do not alter the reply in
this direction the next packet from client sent to vport 20 comes as NEW
connection. We alter it but may be some collision happens for both
conntracks and the second conntrack gets destroyed immediately. The
connection stucks too.
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fix Passive FTP problem in ip_vs_ftp:
- Do not oops in nf_nat_set_seq_adjust (adjust_tcp_sequence) when
iptable_nat module is not loaded
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
use skb->len for accounting as xt_quota does. Since nf_conntrack works
at the network layer, skb_network_offset should always returns ZERO.
Signed-off-by: Changli Gao <xiaosuo@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
This removes duplicate code by providing a default implementation
which is used by 3 of the 4 modules that provide these call.
Signed-off-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Patrick McHardy <kaber@trash.net>
IPVS was merged into the kernel quite a long time ago and
has been seeing wide-spread production use for even longer.
It seems appropriate for it to be no longer tagged as EXPERIMENTAL
Signed-off-as: Simon Horman <horms@verge.net.au>
Signed-off-by: Patrick McHardy <kaber@trash.net>
some users of nf_ct_ext_exist() know ct->ext isn't NULL. For these users, the
check for ct->ext isn't necessary, the function __nf_ct_ext_exist() can be
used instead.
the type of the return value of nf_ct_ext_exist() is changed to bool.
Signed-off-by: Changli Gao <xiaosuo@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
We should copy the initial value to userspace for iptables-save and
to allow removal of specific quota rules.
Signed-off-by: Changli Gao <xiaosuo@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
In some situations a CPU match permits a better spreading of
connections, or select targets only for a given cpu.
With Remote Packet Steering or multiqueue NIC and appropriate IRQ
affinities, we can distribute trafic on available cpus, per session.
(all RX packets for a given flow is handled by a given cpu)
Some legacy applications being not SMP friendly, one way to scale a
server is to run multiple copies of them.
Instead of randomly choosing an instance, we can use the cpu number as a
key so that softirq handler for a whole instance is running on a single
cpu, maximizing cache effects in TCP/UDP stacks.
Using NAT for example, a four ways machine might run four copies of
server application, using a separate listening port for each instance,
but still presenting an unique external port :
iptables -t nat -A PREROUTING -p tcp --dport 80 -m cpu --cpu 0 \
-j REDIRECT --to-port 8080
iptables -t nat -A PREROUTING -p tcp --dport 80 -m cpu --cpu 1 \
-j REDIRECT --to-port 8081
iptables -t nat -A PREROUTING -p tcp --dport 80 -m cpu --cpu 2 \
-j REDIRECT --to-port 8082
iptables -t nat -A PREROUTING -p tcp --dport 80 -m cpu --cpu 3 \
-j REDIRECT --to-port 8083
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Use nf_conntrack/nf_nat code to do the packet mangling and the TCP
sequence adjusting. The function 'ip_vs_skb_replace' is now dead
code, so it is removed.
To SNAT FTP, use something like:
% iptables -t nat -A POSTROUTING -m ipvs --vaddr 192.168.100.30/32 \
--vport 21 -j SNAT --to-source 192.168.10.10
and for the data connections in passive mode:
% iptables -t nat -A POSTROUTING -m ipvs --vaddr 192.168.100.30/32 \
--vportctl 21 -j SNAT --to-source 192.168.10.10
using '-m state --state RELATED' would also works.
Make sure the kernel modules ip_vs_ftp, nf_conntrack_ftp, and
nf_nat_ftp are loaded.
[ up-port and minor fixes by Simon Horman <horms@verge.net.au> ]
Signed-off-by: Hannes Eder <heder@google.com>
Signed-off-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Update the nf_conntrack tuple in reply direction, as we will see
traffic from the real server (RIP) to the client (CIP). Once this is
done we can use netfilters SNAT in POSTROUTING, especially with
xt_ipvs, to do source NAT, e.g.:
% iptables -t nat -A POSTROUTING -m ipvs --vaddr 192.168.100.30/32 --vport 80 \
-j SNAT --to-source 192.168.10.10
[ minor fixes by Simon Horman <horms@verge.net.au> ]
Signed-off-by: Hannes Eder <heder@google.com>
Signed-off-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Patrick McHardy <kaber@trash.net>
This implements the kernel-space side of the netfilter matcher xt_ipvs.
[ minor fixes by Simon Horman <horms@verge.net.au> ]
Signed-off-by: Hannes Eder <heder@google.com>
Signed-off-by: Simon Horman <horms@verge.net.au>
[ Patrick: added xt_ipvs.h to Kbuild ]
Signed-off-by: Patrick McHardy <kaber@trash.net>
This adds a `CHECKSUM' target, which can be used in the iptables mangle
table.
You can use this target to compute and fill in the checksum in
a packet that lacks a checksum. This is particularly useful,
if you need to work around old applications such as dhcp clients,
that do not work well with checksum offloads, but don't want to
disable checksum offload in your device.
The problem happens in the field with virtualized applications.
For reference, see Red Hat bz 605555, as well as
http://www.spinics.net/lists/kvm/msg37660.html
Typical expected use (helps old dhclient binary running in a VM):
iptables -A POSTROUTING -t mangle -p udp --dport bootpc \
-j CHECKSUM --checksum-fill
Includes fixes by Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
This patch adds the missing bits to support the recovery of TCP flows
without disabling window tracking (aka be_liberal). To ensure a
successful recovery, we have to inject the window scale factor via
ctnetlink.
This patch has been tested with a development snapshot of conntrackd
and the new clause `TCPWindowTracking' that allows to perform strict
TCP window tracking recovery across fail-overs.
With this patch, we don't update the receiver's window until it's not
initiated. We require this to perform a successful recovery. Jozsef
confirmed in a private email that this spotted a real issue since that
should not happen.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Acked-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Signed-off-by: Patrick McHardy <kaber@trash.net>
According to the Documentation/CodingStyle, the length of lines should
be within 80.
Signed-off-by: Changli Gao <xiaosuo@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
lvs sctp protocol handler is incorrectly invoked ip_vs_app_pkt_out
Since there's no sctp helpers at present, it does the same thing as
ip_vs_app_pkt_in.
Signed-off-by: Xiaoyu Du <tingsrain@gmail.com>
Acked-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Patrick McHardy <kaber@trash.net>
IP_VS_PROTO_AH_ESP should be set iff either of IP_VS_PROTO_{AH,ESP} is
selected. Express this with standard kconfig syntax.
Signed-off-by: Michal Marek <mmarek@suse.cz>
Acked-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Patrick McHardy <kaber@trash.net>
CONFIG_NF_CT_ACCT has been deprecated for awhile and
was originally scheduled for removal by 2.6.29.
Removing support for this config option also stops
this deprecation warning message in the kernel log.
[ 61.669627] nf_conntrack version 0.5.0 (16384 buckets, 65536 max)
[ 61.669850] CONFIG_NF_CT_ACCT is deprecated and will be removed soon. Please use
[ 61.669852] nf_conntrack.acct=1 kernel parameter, acct=1 nf_conntrack module option or
[ 61.669853] sysctl net.netfilter.nf_conntrack_acct=1 to enable it.
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>
[Patrick: changed default value to 0]
Signed-off-by: Patrick McHardy <kaber@trash.net>
Check at rule install time that CT accounting is enabled. Force it
to be enabled if not while also emitting a warning since this is not
the default state.
This is in preparation for deprecating CONFIG_NF_CT_ACCT upon which
CONFIG_NETFILTER_XT_MATCH_CONNBYTES depended being set.
Added 2 CT accounting support functions:
nf_ct_acct_enabled() - Get CT accounting state.
nf_ct_set_acct() - Enable/disable CT accountuing.
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>
Acked-by: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Destination was spelled wrong in KConfig.
Signed-off-by: Arnd Hannemann <hannemann@nets.rwth-aachen.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Add header file to fix build error:
net/netfilter/xt_IDLETIMER.c:276: error: implicit declaration of function 'MKDEV'
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Allow one-packet scheduling for UDP connections. When the fwmark-based or
normal virtual service is marked with '-o' or '--ops' options all
connections are created only to schedule one packet. Useful to schedule UDP
packets from same client port to different real servers. Recommended with
RR or WRR schedulers (the connections are not visible with ipvsadm -L).
Signed-off-by: Nick Chalk <nick@loadbalancer.org>
Signed-off-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Register net_bridge_port pointer as rx_handler data pointer. As br_port is
removed from struct net_device, another netdev priv_flag is added to indicate
the device serves as a bridge port. Also rcuized pointers are now correctly
dereferenced in br_fdb.c and in netfilter parts.
Signed-off-by: Jiri Pirko <jpirko@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch implements an idletimer Xtables target that can be used to
identify when interfaces have been idle for a certain period of time.
Timers are identified by labels and are created when a rule is set with a new
label. The rules also take a timeout value (in seconds) as an option. If
more than one rule uses the same timer label, the timer will be restarted
whenever any of the rules get a hit.
One entry for each timer is created in sysfs. This attribute contains the
timer remaining for the timer to expire. The attributes are located under
the xt_idletimer class:
/sys/class/xt_idletimer/timers/<label>
When the timer expires, the target module sends a sysfs notification to the
userspace, which can then decide what to do (eg. disconnect to save power).
Cc: Timo Teras <timo.teras@iki.fi>
Signed-off-by: Luciano Coelho <luciano.coelho@nokia.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
- must use atomic_inc_not_zero() in instance_lookup_get()
- must use hlist_add_head_rcu() instead of hlist_add_head()
- must use hlist_del_rcu() instead of hlist_del()
- Introduce NFULNL_COPY_DISABLED to stop lockless reader from using an
instance, before we do final instance_put() on it.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
gen_kill_estimator() API is incomplete or not well documented, since
caller should make sure an RCU grace period is respected before
freeing stats_lock.
This was partially addressed in commit 5d944c640b
(gen_estimator: deadlock fix), but same problem exist for all
gen_kill_estimator() users, if lock they use is not already RCU
protected.
A code review shows xt_RATEEST.c, act_api.c, act_police.c have this
problem. Other are ok because they use qdisc lock, already RCU
protected.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
remove useless union keyword in rtable, rt6_info and dn_route.
Since there is only one member in a union, the union keyword isn't useful.
Signed-off-by: Changli Gao <xiaosuo@gmail.com>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
- instances_lock becomes a spinlock
- lockless lookups
While nfnetlink_log probably not performance critical, using less
rwlocks in our code is always welcomed...
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
- Use an atomic_t for id_sequence to avoid a spin_lock/spin_unlock pair
- Group highly modified struct nfqnl_instance fields together
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
The code that hashes and unhashes connections from the connection table
is missing locking of the connection being modified, which opens up a
race condition and results in memory corruption when this race condition
is hit.
Here is what happens in pretty verbose form:
CPU 0 CPU 1
------------ ------------
An active connection is terminated and
we schedule ip_vs_conn_expire() on this
CPU to expire this connection.
IRQ assignment is changed to this CPU,
but the expire timer stays scheduled on
the other CPU.
New connection from same ip:port comes
in right before the timer expires, we
find the inactive connection in our
connection table and get a reference to
it. We proper lock the connection in
tcp_state_transition() and read the
connection flags in set_tcp_state().
ip_vs_conn_expire() gets called, we
unhash the connection from our
connection table and remove the hashed
flag in ip_vs_conn_unhash(), without
proper locking!
While still holding proper locks we
write the connection flags in
set_tcp_state() and this sets the hashed
flag again.
ip_vs_conn_expire() fails to expire the
connection, because the other CPU has
incremented the reference count. We try
to re-insert the connection into our
connection table, but this fails in
ip_vs_conn_hash(), because the hashed
flag has been set by the other CPU. We
re-schedule execution of
ip_vs_conn_expire(). Now this connection
has the hashed flag set, but isn't
actually hashed in our connection table
and has a dangling list_head.
We drop the reference we held on the
connection and schedule the expire timer
for timeouting the connection on this
CPU. Further packets won't be able to
find this connection in our connection
table.
ip_vs_conn_expire() gets called again,
we think it's already hashed, but the
list_head is dangling and while removing
the connection from our connection table
we write to the memory location where
this list_head points to.
The result will probably be a kernel oops at some other point in time.
This race condition is pretty subtle, but it can be triggered remotely.
It needs the IRQ assignment change or another circumstance where packets
coming from the same ip:port for the same service are being processed on
different CPUs. And it involves hitting the exact time at which
ip_vs_conn_expire() gets called. It can be avoided by making sure that
all packets from one connection are always processed on the same CPU and
can be made harder to exploit by changing the connection timeouts to
some custom values.
Signed-off-by: Sven Wegener <sven.wegener@stealer.net>
Cc: stable@kernel.org
Acked-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Use WORD_ROUND to round an int up to the next multiple of 4.
Signed-off-by: Shan Wei <shanwei@cn.fujitsu.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
NOTRACK makes all cpus share a cache line on nf_conntrack_untracked
twice per packet, slowing down performance.
This patch converts it to a per_cpu variable.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
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>
Use read_pnet() and write_pnet() to reduce number of ifdef CONFIG_NET_NS
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Use atomic_cmpxchg() to avoid dirtying a shared location.
xt_statistic_priv smp aligned to avoid sharing same cache line with
other stuff.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
commit f3c5c1bfd4 (netfilter: xtables: make ip_tables reentrant)
introduced a performance regression, because stackptr array is shared by
all cpus, adding cache line ping pongs. (16 cpus share a 64 bytes cache
line)
Fix this using alloc_percpu()
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Acked-By: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
In xt_register_table, xt_jumpstack_alloc is called first, later
xt_replace_table is used. But in xt_replace_table, xt_jumpstack_alloc
will be used again. Then the memory allocated by previous xt_jumpstack_alloc
will be leaked. We can simply remove the previous xt_jumpstack_alloc because
there aren't any users of newinfo between xt_jumpstack_alloc and
xt_replace_table.
Signed-off-by: Xiaotian Feng <dfeng@redhat.com>
Cc: Patrick McHardy <kaber@trash.net>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jan Engelhardt <jengelh@medozas.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Acked-By: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Eric Dumazet