Commit graph

401 commits

Author SHA1 Message Date
Patrick McHardy
0d53778e81 [NETFILTER]: Convert DEBUGP to pr_debug
Convert DEBUGP to pr_debug and fix lots of non-compiling debug statements.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-10 22:18:20 -07:00
Patrick McHardy
342b7e3c8a [NETFILTER]: xt_helper: use RCU
The ->helper pointer is protected by RCU, no need to take
nf_conntrack_lock. Also remove excessive debugging.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-10 22:18:19 -07:00
Patrick McHardy
91e8db8006 [NETFILTER]: nf_conntrack_h323: turn some printks into DEBUGPs
Don't spam the ringbuffer with decoding errors. The only printks remaining
are for dropped packets when we're certain they are H.323.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-10 22:18:18 -07:00
Patrick McHardy
7ae7730fd6 [NETFILTER]: nf_conntrack: early_drop improvement
When the maximum number of conntrack entries is reached and a new
one needs to be allocated, conntrack tries to drop an unassured
connection from the same hash bucket the new conntrack would hash
to. Since with a properly sized hash the average number of entries
per bucket is 1, the chances of actually finding one are not very
good. This patch makes it walk the hash until a minimum number of
8 entries are checked.

Based on patch by Vasily Averin <vvs@sw.ru>.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-10 22:18:15 -07:00
Patrick McHardy
ec59a1110a [NETFILTER]: nf_conntrack: mark helpers __read_mostly
Most are __read_mostly already, this changes the remaining ones.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-10 22:18:14 -07:00
Patrick McHardy
b8a7fe6c10 [NETFILTER]: nf_conntrack_helper: use hashtable for conntrack helpers
Eliminate the last global list searched for every new connection.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-10 22:18:13 -07:00
Patrick McHardy
f264a7df08 [NETFILTER]: nf_conntrack_expect: introduce nf_conntrack_expect_max sysct
As a last step of preventing DoS by creating lots of expectations, this
patch introduces a global maximum and a sysctl to control it. The default
is initialized to 4 * the expectation hash table size, which results in
1/64 of the default maxmimum of conntracks.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-10 22:18:12 -07:00
Patrick McHardy
b560580a13 [NETFILTER]: nf_conntrack_expect: maintain per conntrack expectation list
This patch brings back the per-conntrack expectation list that was
removed around 2.6.10 to avoid walking all expectations on expectation
eviction and conntrack destruction.

As these were the last users of the global expectation list, this patch
also kills that.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-10 22:18:02 -07:00
Patrick McHardy
31f15875c5 [NETFILTER]: nf_conntrack_helper/nf_conntrack_netlink: convert to expectation hash
Convert from the global expectation list to the hash table.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-10 22:18:01 -07:00
Patrick McHardy
5d08ad440f [NETFILTER]: nf_conntrack_expect: convert proc functions to hash
Convert from the global expectation list to the hash table.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-10 22:18:00 -07:00
Patrick McHardy
a71c085562 [NETFILTER]: nf_conntrack: use hashtable for expectations
Currently all expectations are kept on a global list that

- needs to be searched for every new conncetion
- needs to be walked for evicting expectations when a master connection
  has reached its limit
- needs to be walked on connection destruction for connections that
  have open expectations

This is obviously not good, especially when considering helpers like
H.323 that register *lots* of expectations and can set up permanent
expectations, but it also allows for an easy DoS against firewalls
using connection tracking helpers.

Use a hashtable for expectations to avoid incurring the search overhead
for every new connection. The default hash size is 1/256 of the conntrack
hash table size, this can be overriden using a module parameter.

This patch only introduces the hash table for expectation lookups and
keeps other users to reduce the noise, the following patches will get
rid of it completely.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-10 22:17:59 -07:00
Patrick McHardy
e9c1b084e1 [NETFILTER]: nf_conntrack: move expectaton related init code to nf_conntrack_expect.c
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-10 22:17:58 -07:00
Patrick McHardy
cf6994c2b9 [NETFILTER]: nf_conntrack_netlink: sync expectation dumping with conntrack table dumping
Resync expectation table dumping code with conntrack dumping: don't
rely on the unique ID anymore since that requires to walk the list
backwards, which doesn't work with the upcoming conversion to hlists.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-10 22:17:57 -07:00
Patrick McHardy
4e1d4e6c5a [NETFILTER]: nf_conntrack_expect: avoid useless list walking
Don't walk the list when unexpecting an expectation, we already
have a reference and the timer check is enough to guarantee
that it still is on the list.

This comment suggests that it was copied there by mistake from
expectation eviction:

/* choose the oldest expectation to evict */

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-10 22:17:56 -07:00
Patrick McHardy
d4156e8cd9 [NETFILTER]: nf_conntrack: reduce masks to a subset of tuples
Since conntrack currently allows to use masks for every bit of both
helper and expectation tuples, we can't hash them and have to keep
them on two global lists that are searched for every new connection.

This patch removes the never used ability to use masks for the
destination part of the expectation tuple and completely removes
masks from helpers since the only reasonable choice is a full
match on l3num, protonum and src.u.all.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-10 22:17:55 -07:00
Patrick McHardy
df43b4e7ca [NETFILTER]: nf_conntrack_ftp: use nf_ct_expect_init
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-10 22:17:54 -07:00
Patrick McHardy
6823645d60 [NETFILTER]: nf_conntrack_expect: function naming unification
Currently there is a wild mix of nf_conntrack_expect_, nf_ct_exp_,
expect_, exp_, ...

Consistently use nf_ct_ as prefix for exported functions.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-10 22:17:53 -07:00
Patrick McHardy
ac565e5fc1 [NETFILTER]: nf_conntrack: export hash allocation/destruction functions
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-10 22:17:42 -07:00
Patrick McHardy
330f7db5e5 [NETFILTER]: nf_conntrack: remove 'ignore_conntrack' argument from nf_conntrack_find_get
All callers pass NULL, this also doesn't seem very useful for modules.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-10 22:17:41 -07:00
Patrick McHardy
f205c5e0c2 [NETFILTER]: nf_conntrack: use hlists for conntrack hash
Convert conntrack hash to hlists to reduce its size and cache
footprint. Since the default hashsize to max. entries ratio
sucks (1:16), this patch doesn't reduce the amount of memory
used for the hash by default, but instead uses a better ratio
of 1:8, which results in the same max. entries value.

One thing worth noting is early_drop. It really should use LRU,
so it now has to iterate over the entire chain to find the last
unconfirmed entry. Since chains shouldn't be very long and the
entire operation is very rare this shouldn't be a problem.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-10 22:17:40 -07:00
Patrick McHardy
8e5105a0c3 [NETFILTER]: nf_conntrack: round up hashsize to next multiple of PAGE_SIZE
Don't let the rest of the page go to waste.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-10 22:17:39 -07:00
Patrick McHardy
61eb3107cd [NETFILTER]: nf_conntrack_extend: use __read_mostly for struct nf_ct_ext_type
Also make them static.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-10 22:17:38 -07:00
Yasuyuki Kozakai
d8a0509a69 [NETFILTER]: nf_nat: kill global 'destroy' operation
This kills the global 'destroy' operation which was used by NAT.
Instead it uses the extension infrastructure so that multiple
extensions can register own operations.

Signed-off-by: Yasuyuki Kozakai <yasuyuki.kozakai@toshiba.co.jp>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-10 22:17:36 -07:00
Yasuyuki Kozakai
dacd2a1a5c [NETFILTER]: nf_conntrack: remove old memory allocator of conntrack
Now memory space for help and NAT are allocated by extension
infrastructure.

Signed-off-by: Yasuyuki Kozakai <yasuyuki.kozakai@toshiba.co.jp>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-10 22:17:35 -07:00
Yasuyuki Kozakai
ceceae1b15 [NETFILTER]: nf_conntrack: use extension infrastructure for helper
Signed-off-by: Yasuyuki Kozakai <yasuyuki.kozakai@toshiba.co.jp>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-10 22:17:18 -07:00
Yasuyuki Kozakai
ecfab2c9fe [NETFILTER]: nf_conntrack: introduce extension infrastructure
Old space allocator of conntrack had problems about extensibility.
- It required slab cache per combination of extensions.
- It expected what extensions would be assigned, but it was impossible
  to expect that completely, then we allocated bigger memory object than
  really required.
- It needed to search helper twice due to lock issue.

Now basic informations of a connection are stored in 'struct nf_conn'.
And a storage for extension (helper, NAT) is allocated by kmalloc.

Signed-off-by: Yasuyuki Kozakai <yasuyuki.kozakai@toshiba.co.jp>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-10 22:17:17 -07:00
Patrick McHardy
9f15c5302d [NETFILTER]: x_tables: mark matches and targets __read_mostly
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-10 22:17:15 -07:00
Jozsef Kadlecsik
ba9dda3ab5 [NETFILTER]: x_tables: add TRACE target
The TRACE target can be used to follow IP and IPv6 packets through
the ruleset.

Signed-off-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Signed-off-by: Patrick NcHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-10 22:17:14 -07:00
Jan Engelhardt
1b50b8a371 [NETFILTER]: Add u32 match
Along comes... xt_u32, a revamped ipt_u32 from POM-NG,
Plus:

    *	2007-06-02: added ipv6 support

    *	2007-06-05: uses kmalloc for the big buffer

    *   2007-06-05: added inversion

    *   2007-06-20: use skb_copy_bits() and get rid of the big buffer
        and lock (suggested by Pablo Neira Ayuso)

Signed-off-by: Jan Engelhardt <jengelh@gmx.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-10 22:17:13 -07:00
Jan Engelhardt
7c4e36bc17 [NETFILTER]: Remove redundant parentheses/braces
Removes redundant parentheses and braces (And add one pair in a
xt_tcpudp.c macro).

Signed-off-by: Jan Engelhardt <jengelh@gmx.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-10 22:17:11 -07:00
Jan Engelhardt
a47362a226 [NETFILTER]: add some consts, remove some casts
Make a number of variables const and/or remove unneeded casts.

Signed-off-by: Jan Engelhardt <jengelh@gmx.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-10 22:17:01 -07:00
Jan Engelhardt
e1931b784a [NETFILTER]: x_tables: switch xt_target->checkentry to bool
Switch the return type of target checkentry functions to boolean.

Signed-off-by: Jan Engelhardt <jengelh@gmx.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-10 22:16:59 -07:00
Jan Engelhardt
ccb79bdce7 [NETFILTER]: x_tables: switch xt_match->checkentry to bool
Switch the return type of match functions to boolean

Signed-off-by: Jan Engelhardt <jengelh@gmx.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-10 22:16:58 -07:00
Jan Engelhardt
1d93a9cbad [NETFILTER]: x_tables: switch xt_match->match to bool
Switch the return type of match functions to boolean

Signed-off-by: Jan Engelhardt <jengelh@gmx.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-10 22:16:57 -07:00
Jan Engelhardt
cff533ac12 [NETFILTER]: x_tables: switch hotdrop to bool
Switch the "hotdrop" variables to boolean

Signed-off-by: Jan Engelhardt <jengelh@gmx.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-10 22:16:56 -07:00
Jing Min Zhao
558585aad0 [NETFILTER]: nf_conntrack_h323: check range first in sequence extension
Check range before checking STOP flag. This optimization may save a
nanosecond or less :)

Signed-off-by: Jing Min Zhao <zhaojingmin@vivecode.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-10 22:16:54 -07:00
Patrick McHardy
334a8132d9 [SKBUFF]: Keep track of writable header len of headerless clones
Currently NAT (and others) that want to modify cloned skbs copy them,
even if in the vast majority of cases its not necessary because the
skb is a clone made by TCP and the portion NAT wants to modify is
actually writable because TCP release the header reference before
cloning.

The problem is that there is no clean way for NAT to find out how
long the writable header area is, so this patch introduces skb->hdr_len
to hold this length. When a headerless skb is cloned skb->hdr_len
is set to the current headroom, for regular clones it is copied from
the original. A new function skb_clone_writable(skb, len) returns
whether the skb is writable up to len bytes from skb->data. To avoid
enlarging the skb the mac_len field is reduced to 16 bit and the
new hdr_len field is put in the remaining 16 bit.

I've done a few rough benchmarks of NAT (not with this exact patch,
but a very similar one). As expected it saves huge amounts of system
time in case of sendfile, bringing it down to basically the same
amount as without NAT, with sendmsg it only helps on loopback,
probably because of the large MTU.

Transmit a 1GB file using sendfile/sendmsg over eth0/lo with and
without NAT:

- sendfile eth0, no NAT:	sys     0m0.388s
- sendfile eth0, NAT:		sys     0m1.835s
- sendfile eth0: NAT + path:	sys     0m0.370s	(~ -80%)

- sendfile lo, no NAT:		sys     0m0.258s
- sendfile lo, NAT:		sys     0m2.609s
- sendfile lo, NAT + patch:	sys     0m0.260s	(~ -90%)

- sendmsg eth0, no NAT:		sys     0m2.508s
- sendmsg eth0, NAT:		sys     0m2.539s
- sendmsg eth0, NAT + patch:	sys     0m2.445s	(no change)

- sendmsg lo, no NAT:		sys	0m2.151s
- sendmsg lo, NAT:		sys     0m3.557s
- sendmsg lo, NAT + patch:	sys     0m2.159s	(~ -40%)

I expect other users can see a similar performance improvement,
packet mangling iptables targets, ipip and ip_gre come to mind ..

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-10 22:15:37 -07:00
Jing Min Zhao
25845b5155 [NETFILTER]: nf_conntrack_h323: add checking of out-of-range on choices' index values
Choices' index values may be out of range while still encoded in the fixed
length bit-field. This bug may cause access to undefined types (NULL
pointers) and thus crashes (Reported by Zhongling Wen).

This patch also adds checking of decode flag when decoding SEQUENCEs.

Signed-off-by: Jing Min Zhao <zhaojingmin@vivecode.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-05 17:40:23 -07:00
Yasuyuki Kozakai
e2d8e314ad [NETFILTER]: nfctnetlink: Don't allow to change helper
There is no realistic situation to change helper (Who wants IRC helper to
track FTP traffic ?). Moreover, if we want to do that, we need to fix race
issue by nfctnetlink and running helper. That will add overhead to packet
processing. It wouldn't pay. So this rejects the request to change
helper. The requests to add or remove helper are accepted as ever.

Signed-off-by: Yasuyuki Kozakai <yasuyuki.kozakai@toshiba.co.jp>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-06-22 14:10:22 -07:00
Jerome Borsboom
d258131aae [NETFILTER]: nf_conntrack_sip: add missing message types containing RTP info
Signed-off-by: Jerome Borsboom <j.borsboom@erasmusmc.nl>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-06-22 14:08:17 -07:00
Akinobu Mita
c764c9ade6 [NETFILTER]: nf_conntrack_amanda: fix textsearch_prepare() error check
The return value from textsearch_prepare() needs to be checked
by IS_ERR(). Because it returns error code as a pointer.

Cc: "Brian J. Murrell" <netfilter@interlinx.bc.ca>
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-06-07 13:40:38 -07:00
Patrick McHarrdy
3c158f7f57 [NETFILTER]: nf_conntrack: fix helper module unload races
When a helper module is unloaded all conntracks refering to it have their
helper pointer NULLed out, leading to lots of races. In most places this
can be fixed by proper use of RCU (they do already check for != NULL,
but in a racy way), additionally nf_conntrack_expect_related needs to
bail out when no helper is present.

Also remove two paranoid BUG_ONs in nf_conntrack_proto_gre that are racy
and not worth fixing.

Signed-off-by: Patrick McHarrdy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-06-07 13:40:26 -07:00
Jing Min Zhao
f8f1c08eae [NETFILTER]: nf_conntrack_h323: add missing T.120 address in OLCA
Add missing process of T.120 address in OpenLogicalChannelAck signal.

Signed-off-by: Jing Min Zhao <zhaojingmin@vivecode.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-05-24 16:44:11 -07:00
Jing Min Zhao
596830f1a1 [NETFILTER]: nf_conntrack_h323: remove unnecessary process of Information signal
According to the implementation of H.323, it's not necessary to check
the addresses in Information signals.

Signed-off-by: Jing Min Zhao <zhaojingmin@vivecode.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-05-24 16:43:42 -07:00
Jing Min Zhao
bb807245ef [NETFILTER]: nf_conntrack_h323: fix get_h225_addr() for IPv6 address access
Update get_h225_addr() to meet the changes in ASN.1 types. It was using
field ip6 to access IPv6 TransportAddress, it should be ip according the
ASN.1 definition.

Signed-off-by: Jing Min Zhao <zhaojingmin@vivecode.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-05-24 16:43:07 -07:00
Jing Min Zhao
d052918688 [NETFILTER]: nf_conntrack_h323: fix ASN.1 types
1. Add support for decoding IPv6 address. I know it was manually added in
   the header file, but not in the template file. That wouldn't work.
2. Add missing support for decoding T.120 address in OLCA.
3. Remove unnecessary decoding of Information signal.

Signed-off-by: Jing Min Zhao <zhaojingmin@vivecode.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-05-24 16:42:26 -07:00
Patrick McHardy
25b86e0546 [NETFILTER]: nf_conntrack_ftp: fix newline sequence number calculation
When the packet size is changed by the FTP NAT helper, the connection
tracking helper adjusts the sequence number of the newline character
by the size difference. This is wrong because NAT sequence number
adjustment happens after helpers are called, so the unadjusted number
is compared to the already adjusted one.

Based on report by YU, Haitao <yuhaitao@tsinghua.org.cn>

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-05-24 16:41:50 -07:00
Patrick McHardy
5fe26f53fe [NETFILTER]: nf_conntrack_ftp: fix newline sequence number update
When trying to locate the oldest entry in the history of newline character
sequence numbers, the sequence number of the current entry is incorrectly
compared with the index of the oldest sequence number instead of the number
itself.

Additionally it is not made sure that the current sequence number really
is after the oldest known one.

Based on report by YU, Haitao <yuhaitao@tsinghua.org.cn>

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-05-24 16:40:51 -07:00
Patrick McHardy
5397e97d75 [NETFILTER]: nf_conntrack: fix use-after-free in helper destroy callback invocation
When the helper module is removed for a master connection that has a
fulfilled expectation, but has already timed out and got removed from
the hash tables, nf_conntrack_helper_unregister can't find the master
connection to unset the helper, causing a use-after-free when the
expected connection is destroyed and releases the last reference to
the master.

The helper destroy callback was introduced for the PPtP helper to clean
up expectations and expected connections when the master connection
times out, but doing this from destroy_conntrack only works for
unfulfilled expectations since expected connections hold a reference
to the master, preventing its destruction. Move the destroy callback to
the timeout function, which fixes both problems.

Reported/tested by Gabor Burjan <buga@buvoshetes.hu>.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-05-19 14:23:52 -07:00
Patrick McHardy
da0dd23143 [NETFILTER]: xt_conntrack: add compat support
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-05-10 23:48:00 -07:00