Make all initialized struct seq_operations in net/ const
Signed-off-by: Philippe De Muyter <phdm@macqel.be>
Signed-off-by: David S. Miller <davem@davemloft.net>
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>
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>
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>
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>
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>
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>
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>
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>
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Many struct file_operations in the kernel can be "const". Marking them const
moves these to the .rodata section, which avoids false sharing with potential
dirty data. In addition it'll catch accidental writes at compile time to
these shared resources.
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Replace all uses of kmem_cache_t with struct kmem_cache.
The patch was generated using the following script:
#!/bin/sh
#
# Replace one string by another in all the kernel sources.
#
set -e
for file in `find * -name "*.c" -o -name "*.h"|xargs grep -l $1`; do
quilt add $file
sed -e "1,\$s/$1/$2/g" $file >/tmp/$$
mv /tmp/$$ $file
quilt refresh
done
The script was run like this
sh replace kmem_cache_t "struct kmem_cache"
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The original code continues loop to find expectation in list if the master
conntrack of the found expectation is unconfirmed. But it never success
in that case, because nf_conntrack_expect_related() never insert
clashed expectation to the list.
This stops loop in that case.
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>
- move EXPORT_SYMBOL next to exported symbol
- use EXPORT_SYMBOL_GPL since this is what the original code used
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Expectation address masks need to be differently initialized depending
on the address family, create helper function to avoid cluttering up
the code too much.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
We usually uses 'xxx_find_get' for function which increments
reference count.
Signed-off-by: Yasuyuki Kozakai <yasuyuki.kozakai@toshiba.co.jp>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Rename 'struct nf_conntrack_protocol' to 'struct nf_conntrack_l4proto' in
order to help distinguish it from 'struct nf_conntrack_l3proto'. It gets
rather confusing with 'nf_conntrack_protocol'.
Signed-off-by: Martin Josefsson <gandalf@wlug.westbo.se>
Signed-off-by: Patrick McHardy <kaber@trash.net>
This patch splits out expectation handling into its own file
nf_conntrack_expect.c
Signed-off-by: Martin Josefsson <gandalf@wlug.westbo.se>
Signed-off-by: Patrick McHardy <kaber@trash.net>