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git://git.kernel.org/pub/scm/linux/kernel/git/kaber/nf-2.6
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Commit acc738fe (netfilter: xtables: avoid pointer to self) introduced
an invalid return value in limit_mt_check().
Signed-off-by: Patrick McHardy <kaber@trash.net>
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seq_show()
[ 171.925285] BUG: sleeping function called from invalid context at kernel/mutex.c:280
[ 171.925296] in_atomic(): 1, irqs_disabled(): 0, pid: 671, name: grep
[ 171.925306] 2 locks held by grep/671:
[ 171.925312] #0: (&p->lock){+.+.+.}, at: [<c10b8acd>] seq_read+0x25/0x36c
[ 171.925340] #1: (rcu_read_lock){.+.+..}, at: [<c1391dac>] seq_start+0x0/0x44
[ 171.925372] Pid: 671, comm: grep Not tainted 2.6.31.6-4-netbook #3
[ 171.925380] Call Trace:
[ 171.925398] [<c105104e>] ? __debug_show_held_locks+0x1e/0x20
[ 171.925414] [<c10264ac>] __might_sleep+0xfb/0x102
[ 171.925430] [<c1461521>] mutex_lock_nested+0x1c/0x2ad
[ 171.925444] [<c1391c9e>] seq_show+0x74/0x127
[ 171.925456] [<c10b8c5c>] seq_read+0x1b4/0x36c
[ 171.925469] [<c10b8aa8>] ? seq_read+0x0/0x36c
[ 171.925483] [<c10d5c8e>] proc_reg_read+0x60/0x74
[ 171.925496] [<c10d5c2e>] ? proc_reg_read+0x0/0x74
[ 171.925510] [<c10a4468>] vfs_read+0x87/0x110
[ 171.925523] [<c10a458a>] sys_read+0x3b/0x60
[ 171.925538] [<c1002a49>] syscall_call+0x7/0xb
Fix it by replacing RCU with nf_log_mutex.
Reported-by: "Yin, Kangkai" <kangkai.yin@intel.com>
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Return a negative error value.
Signed-off-by: Roel Kluin <roel.kluin@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
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seq_show()
[ 171.925285] BUG: sleeping function called from invalid context at kernel/mutex.c:280
[ 171.925296] in_atomic(): 1, irqs_disabled(): 0, pid: 671, name: grep
[ 171.925306] 2 locks held by grep/671:
[ 171.925312] #0: (&p->lock){+.+.+.}, at: [<c10b8acd>] seq_read+0x25/0x36c
[ 171.925340] #1: (rcu_read_lock){.+.+..}, at: [<c1391dac>] seq_start+0x0/0x44
[ 171.925372] Pid: 671, comm: grep Not tainted 2.6.31.6-4-netbook #3
[ 171.925380] Call Trace:
[ 171.925398] [<c105104e>] ? __debug_show_held_locks+0x1e/0x20
[ 171.925414] [<c10264ac>] __might_sleep+0xfb/0x102
[ 171.925430] [<c1461521>] mutex_lock_nested+0x1c/0x2ad
[ 171.925444] [<c1391c9e>] seq_show+0x74/0x127
[ 171.925456] [<c10b8c5c>] seq_read+0x1b4/0x36c
[ 171.925469] [<c10b8aa8>] ? seq_read+0x0/0x36c
[ 171.925483] [<c10d5c8e>] proc_reg_read+0x60/0x74
[ 171.925496] [<c10d5c2e>] ? proc_reg_read+0x0/0x74
[ 171.925510] [<c10a4468>] vfs_read+0x87/0x110
[ 171.925523] [<c10a458a>] sys_read+0x3b/0x60
[ 171.925538] [<c1002a49>] syscall_call+0x7/0xb
Fix it by replacing RCU with nf_log_mutex.
Reported-by: "Yin, Kangkai" <kangkai.yin@intel.com>
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
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Return a negative error value.
Signed-off-by: Roel Kluin <roel.kluin@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
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* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (34 commits)
net/fsl_pq_mdio: add module license GPL
can: fix WARN_ON dump in net/core/rtnetlink.c:rtmsg_ifinfo()
can: should not use __dev_get_by_index() without locks
hisax: remove bad udelay call to fix build error on ARM
ipip: Fix handling of DF packets when pmtudisc is OFF
qlge: Set PCIe reset type for EEH to fundamental.
qlge: Fix early exit from mbox cmd complete wait.
ixgbe: fix traffic hangs on Tx with ioatdma loaded
ixgbe: Fix checking TFCS register for TXOFF status when DCB is enabled
ixgbe: Fix gso_max_size for 82599 when DCB is enabled
macsonic: fix crash on PowerBook 520
NET: cassini, fix lock imbalance
ems_usb: Fix byte order issues on big endian machines
be2net: Bug fix to send config commands to hardware after netdev_register
be2net: fix to set proper flow control on resume
netfilter: xt_connlimit: fix regression caused by zero family value
rt2x00: Don't queue ieee80211 work after USB removal
Revert "ipw2200: fix oops on missing firmware"
decnet: netdevice refcount leak
netfilter: nf_nat: fix NAT issue in 2.6.30.4+
...
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Commit v2.6.28-rc1~717^2~109^2~2 was slightly incomplete; not all
instances of par->match->family were changed to par->family.
References: http://bugzilla.netfilter.org/show_bug.cgi?id=610
Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Vitezslav Samel discovered that since 2.6.30.4+ active FTP can not work
over NAT. The "cause" of the problem was a fix of unacknowledged data
detection with NAT (commit a3a9f79e361e864f0e9d75ebe2a0cb43d17c4272).
However, actually, that fix uncovered a long standing bug in TCP conntrack:
when NAT was enabled, we simply updated the max of the right edge of
the segments we have seen (td_end), by the offset NAT produced with
changing IP/port in the data. However, we did not update the other parameter
(td_maxend) which is affected by the NAT offset. Thus that could drift
away from the correct value and thus resulted breaking active FTP.
The patch below fixes the issue by *not* updating the conntrack parameters
from NAT, but instead taking into account the NAT offsets in conntrack in a
consistent way. (Updating from NAT would be more harder and expensive because
it'd need to re-calculate parameters we already calculated in conntrack.)
Signed-off-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
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After m68k's task_thread_info() doesn't refer to current,
it's possible to remove sched.h from interrupt.h and not break m68k!
Many thanks to Heiko Carstens for allowing this.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
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This provides safety against negative optlen at the type
level instead of depending upon (sometimes non-trivial)
checks against this sprinkled all over the the place, in
each and every implementation.
Based upon work done by Arjan van de Ven and feedback
from Linus Torvalds.
Signed-off-by: David S. Miller <davem@davemloft.net>
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It's unused.
It isn't needed -- read or write flag is already passed and sysctl
shouldn't care about the rest.
It _was_ used in two places at arch/frv for some reason.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: David Howells <dhowells@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: James Morris <jmorris@namei.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Sizing of memory allocations shouldn't depend on the number of physical
pages found in a system, as that generally includes (perhaps a huge amount
of) non-RAM pages. The amount of what actually is usable as storage
should instead be used as a basis here.
Some of the calculations (i.e. those not intending to use high memory)
should likely even use (totalram_pages - totalhigh_pages).
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: Dave Airlie <airlied@linux.ie>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Hugh Dickins <hugh.dickins@tiscali.co.uk>
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>
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git://git.kernel.org/pub/scm/linux/kernel/git/kaber/nf-next-2.6
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master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
Conflicts:
drivers/net/yellowfin.c
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Add handling of incoming ICMPv6 messages.
This follows the handling of IPv4 ICMP messages.
Amongst ther things this problem allows IPVS to behave sensibly
when an ICMPV6_PKT_TOOBIG message is received:
This message is received when a realserver sends a packet >PMTU to the
client. The hop on this path with insufficient MTU will generate an
ICMPv6 Packet Too Big message back to the VIP. The LVS server receives
this message, but the call to the function handling this has been
missing. Thus, IPVS fails to forward the message to the real server,
which then does not adjust the path MTU. This patch adds the missing
call to ip_vs_in_icmp_v6() in ip_vs_in() to handle this situation.
Thanks to Rob Gallagher from HEAnet for reporting this issue and for
testing this patch in production (with direct routing mode).
[horms@verge.net.au: tweaked changelog]
Signed-off-by: Julius Volz <julius.volz@gmail.com>
Tested-by: Rob Gallagher <robert.gallagher@heanet.ie>
Signed-off-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Patrick McHardy <kaber@trash.net>
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Conntracks in netns other than init_net dying list were never killed.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Patrick McHardy <kaber@trash.net>
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A pointed out by Shin Hong, IPVS doesn't always use atomic operations
in an atomic manner. While this seems unlikely to be manifest in
strange behaviour, it seems appropriate to clean this up.
Cc: shin hong <hongshin@gmail.com>
Signed-off-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Patrick McHardy <kaber@trash.net>
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Signed-off-by: Patrick McHardy <kaber@trash.net>
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The inputted table is never modified, so should be considered const.
Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
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Success was indicated on a memory allocation failure, thereby causing
a crash due to a later NULL deref.
(Affects v2.6.30-rc1 up to here.)
Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
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In 5e140dfc1fe87eae27846f193086724806b33c7d "net: reorder struct Qdisc
for better SMP performance" the definition of struct gnet_stats_basic
changed incompatibly, as copies of this struct are shipped to
userland via netlink.
Restoring old behavior is not welcome, for performance reason.
Fix is to use a private structure for kernel, and
teach gnet_stats_copy_basic() to convert from kernel to user land,
using legacy structure (struct gnet_stats_basic)
Based on a report and initial patch from Michael Spang.
Reported-by: Michael Spang <mspang@csclub.uwaterloo.ca>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Superseded by xt_owner v1 (v2.6.24-2388-g0265ab4).
Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
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Superseded by xt_mark v1 (v2.6.24-2922-g17b0d7e).
Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
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Superseded by xt_iprange v1 (v2.6.24-2928-g1a50c5a1).
Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
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Superseded by xt_conntrack v1 (v2.6.24-2921-g64eb12f).
Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
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Superseded by xt_connmark v1 (v2.6.24-2919-g96e3227).
Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
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Superseded by xt_MARK v2 (v2.6.24-2918-ge0a812a).
Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
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Superseded by xt_CONNMARK v1 (v2.6.24-2917-g0dc8c76).
Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
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Superseded by xt_TOS v1 (v2.6.24-2396-g5c350e5).
Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
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String literals are constant, and usually, we can also tag the array
of pointers const too, moving it to the .rodata section.
Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Since pr_err and friends are used instead of printk there is no point
in keeping IP_VS_ERR and friends. Furthermore make use of '__func__'
instead of hard coded function names.
Signed-off-by: Hannes Eder <heder@google.com>
Acked-by: Simon Horman <horms@verge.net.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
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While being at it cleanup whitespace.
Signed-off-by: Hannes Eder <heder@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
Conflicts:
drivers/net/wireless/orinoco/main.c
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When a slab cache uses SLAB_DESTROY_BY_RCU, we must be careful when allocating
objects, since slab allocator could give a freed object still used by lockless
readers.
In particular, nf_conntrack RCU lookups rely on ct->tuplehash[xxx].hnnode.next
being always valid (ie containing a valid 'nulls' value, or a valid pointer to next
object in hash chain.)
kmem_cache_zalloc() setups object with NULL values, but a NULL value is not valid
for ct->tuplehash[xxx].hnnode.next.
Fix is to call kmem_cache_alloc() and do the zeroing ourself.
As spotted by Patrick, we also need to make sure lookup keys are committed to
memory before setting refcount to 1, or a lockless reader could get a reference
on the old version of the object. Its key re-check could then pass the barrier.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
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The first argument is the address family, the second one the hook
number.
Signed-off-by: Patrick McHardy <kaber@trash.net>
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This makes generic netlink network namespace aware. No
generic netlink families except for the controller family
are made namespace aware, they need to be checked one by
one and then set the family->netnsok member to true.
A new function genlmsg_multicast_netns() is introduced to
allow sending a multicast message in a given namespace,
for example when it applies to an object that lives in
that namespace, a new function genlmsg_multicast_allns()
to send a message to all network namespaces (for objects
that do not have an associated netns).
The function genlmsg_multicast() is changed to multicast
the message in just init_net, which is currently correct
for all generic netlink families since they only work in
init_net right now. Some will later want to work in all
net namespaces because they do not care about the netns
at all -- those will have to be converted to use one of
the new functions genlmsg_multicast_allns() or
genlmsg_multicast_netns() whenever they are made netns
aware in some way.
After this patch families can easily decide whether or
not they should be available in all net namespaces. Many
genl families us it for objects not related to networking
and should therefore be available in all namespaces, but
that will have to be done on a per family basis.
Note that this doesn't touch on the checkpoint/restart
problem where network namespaces could be used, genl
families and multicast groups are numbered globally and
I see no easy way of changing that, especially since it
must be possible to multicast to all network namespaces
for those families that do not care about netns.
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
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As reported by Philip, the UNTRACKED state bit does not fit within
the 8-bit state_mask member. Enlarge state_mask and give status_mask
a few more bits too.
Reported-by: Philip Craig <philipc@snapgear.com>
References: http://markmail.org/thread/b7eg6aovfh4agyz7
Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
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When NAT helpers change the TCP packet size, the highest seen sequence
number needs to be corrected. This is currently only done upwards, when
the packet size is reduced the sequence number is unchanged. This causes
TCP conntrack to falsely detect unacknowledged data and decrease the
timeout.
Fix by updating the highest seen sequence number in both directions after
packet mangling.
Tested-by: Krzysztof Piotr Oledzki <ole@ans.pl>
Signed-off-by: Patrick McHardy <kaber@trash.net>
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RCU barriers, rcu_barrier(), is inserted two places.
In nf_conntrack_expect.c nf_conntrack_expect_fini() before the
kmem_cache_destroy(). Firstly to make sure the callback to the
nf_ct_expect_free_rcu() code is still around. Secondly because I'm
unsure about the consequence of having in flight
nf_ct_expect_free_rcu/kmem_cache_free() calls while doing a
kmem_cache_destroy() slab destroy.
And in nf_conntrack_extend.c nf_ct_extend_unregister(), inorder to
wait for completion of callbacks to __nf_ct_ext_free_rcu(), which is
invoked by __nf_ct_ext_add(). It might be more efficient to call
rcu_barrier() in nf_conntrack_core.c nf_conntrack_cleanup_net(), but
thats make it more difficult to read the code (as the callback code
in located in nf_conntrack_extend.c).
Signed-off-by: Jesper Dangaard Brouer <hawk@comx.dk>
Signed-off-by: Patrick McHardy <kaber@trash.net>
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As noticed by Török Edwin <edwintorok@gmail.com>:
Compiling the kernel with clang has shown this warning:
net/netfilter/xt_rateest.c:69:16: warning: self-comparison always results in a
constant value
ret &= pps2 == pps2;
^
Looking at the code:
if (info->flags & XT_RATEEST_MATCH_BPS)
ret &= bps1 == bps2;
if (info->flags & XT_RATEEST_MATCH_PPS)
ret &= pps2 == pps2;
Judging from the MATCH_BPS case it seems to be a typo, with the intention of
comparing pps1 with pps2.
http://bugzilla.kernel.org/show_bug.cgi?id=13535
Signed-off-by: Patrick McHardy <kaber@trash.net>
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Commit v2.6.29-rc5-872-gacc738f ("xtables: avoid pointer to self")
forgot to copy the initial quota value supplied by iptables into the
private structure, thus counting from whatever was in the memory
kmalloc returned.
Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
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Signed-off-by: Patrick McHardy <kaber@trash.net>
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net/netfilter/xt_NFQUEUE.c:46:9: warning: incorrect type in assignment (different base types)
net/netfilter/xt_NFQUEUE.c:46:9: expected unsigned int [unsigned] [usertype] ipaddr
net/netfilter/xt_NFQUEUE.c:46:9: got restricted unsigned int
net/netfilter/xt_NFQUEUE.c:68:10: warning: incorrect type in assignment (different base types)
net/netfilter/xt_NFQUEUE.c:68:10: expected unsigned int [unsigned] <noident>
net/netfilter/xt_NFQUEUE.c:68:10: got restricted unsigned int
net/netfilter/xt_NFQUEUE.c:69:10: warning: incorrect type in assignment (different base types)
net/netfilter/xt_NFQUEUE.c:69:10: expected unsigned int [unsigned] <noident>
net/netfilter/xt_NFQUEUE.c:69:10: got restricted unsigned int
net/netfilter/xt_NFQUEUE.c:70:10: warning: incorrect type in assignment (different base types)
net/netfilter/xt_NFQUEUE.c:70:10: expected unsigned int [unsigned] <noident>
net/netfilter/xt_NFQUEUE.c:70:10: got restricted unsigned int
net/netfilter/xt_NFQUEUE.c:71:10: warning: incorrect type in assignment (different base types)
net/netfilter/xt_NFQUEUE.c:71:10: expected unsigned int [unsigned] <noident>
net/netfilter/xt_NFQUEUE.c:71:10: got restricted unsigned int
net/netfilter/xt_cluster.c:20:55: warning: incorrect type in return expression (different base types)
net/netfilter/xt_cluster.c:20:55: expected unsigned int
net/netfilter/xt_cluster.c:20:55: got restricted unsigned int const [usertype] ip
net/netfilter/xt_cluster.c:20:55: warning: incorrect type in return expression (different base types)
net/netfilter/xt_cluster.c:20:55: expected unsigned int
net/netfilter/xt_cluster.c:20:55: got restricted unsigned int const [usertype] ip
Signed-off-by: Patrick McHardy <kaber@trash.net>
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The RCU protected conntrack hash lookup only checks whether the entry
has a refcount of zero to decide whether it is stale. This is not
sufficient, entries are explicitly removed while there is at least
one reference left, possibly more. Explicitly check whether the entry
has been marked as dying to fix this.
Signed-off-by: Patrick McHardy <kaber@trash.net>
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New connection tracking entries are inserted into the hash before they
are fully set up, namely the CONFIRMED bit is not set and the timer not
started yet. This can theoretically lead to a race with timer, which
would set the timeout value to a relative value, most likely already in
the past.
Perform hash insertion as the final step to fix this.
Signed-off-by: Patrick McHardy <kaber@trash.net>
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death_by_timeout() might delete a conntrack from hash list
and insert it in dying list.
nf_ct_delete_from_lists(ct);
nf_ct_insert_dying_list(ct);
I believe a (lockless) reader could *catch* ct while doing a lookup
and miss the end of its chain.
(nulls lookup algo must check the null value at the end of lookup and
should restart if the null value is not the expected one.
cf Documentation/RCU/rculist_nulls.txt for details)
We need to change nf_conntrack_init_net() and use a different "null" value,
guaranteed not being used in regular lists. Choose very large values, since
hash table uses [0..size-1] null values.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Patrick McHardy <kaber@trash.net>
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master.kernel.org:/pub/scm/linux/kernel/git/torvalds/linux-2.6
Conflicts:
Documentation/feature-removal-schedule.txt
drivers/scsi/fcoe/fcoe.c
net/core/drop_monitor.c
net/core/net-traces.c
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Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
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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>
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