Imagine such situation, nf_conntrack_htable_size now is 4096, we are doing
ctnl_untimeout, and iterate on 3000# bucket.
Meanwhile, another user try to reduce hash size to 2048, then all nf_conn
are removed to the new hashtable. When this hash resize operation finished,
we still try to itreate ct begin from 3000# bucket, find nothing to do and
just return.
We may miss unlinking some timeout objects. And later we will end up with
invalid references to timeout object that are already gone.
So when we find that hash resize happened, try to unlink timeout objects
from the 0# bucket again.
Signed-off-by: Liping Zhang <liping.zhang@spreadtrum.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
We already include netns address in the hash and compare the netns pointers
during lookup, so even if namespaces have overlapping addresses entries
will be spread across the table.
Assuming 64k bucket size, this change saves 0.5 mbyte per namespace on a
64bit system.
NAT bysrc and expectation hash is still per namespace, those will
changed too soon.
Future patch will also make conntrack object slab cache global again.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The spin_unlock call should have been left as-is, revert.
Fixes: b16c29191d ("netfilter: nf_conntrack: use safer way to lock all buckets")
Reported-by: kernel test robot <fengguang.wu@intel.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
When we need to lock all buckets in the connection hashtable we'd attempt to
lock 1024 spinlocks, which is way more preemption levels than supported by
the kernel. Furthermore, this behavior was hidden by checking if lockdep is
enabled, and if it was - use only 8 buckets(!).
Fix this by using a global lock and synchronize all buckets on it when we
need to lock them all. This is pretty heavyweight, but is only done when we
need to resize the hashtable, and that doesn't happen often enough (or at all).
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Reviewed-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The object and module refcounts are updated for each conntrack template,
however, if we delete the iptables rules and we flush the timeout
database, we may end up with invalid references to timeout object that
are just gone.
Resolve this problem by setting the timeout reference to NULL when the
custom timeout entry is removed from our base. This patch requires some
RCU trickery to ensure safe pointer handling.
This handling is similar to what we already do with conntrack helpers,
the idea is to avoid bumping the timeout object reference counter from
the packet path to avoid the cost of atomic ops.
Reported-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Default timeouts are currently set via proc/sysctl interface, the
typical pattern is a file name like:
/proc/sys/net/netfilter/nf_conntrack_PROTOCOL_timeout_STATE
This results in one entry per default protocol state timeout.
This patch simplifies this by allowing to set default protocol
timeouts via cttimeout netlink interface.
This should allow us to get rid of the existing proc/sysctl code
in the midterm.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
These are the only calls under net/ that do not check nla_parse_nested()
for its error code, but simply continue execution. If parsing of netlink
attributes fails, we should return with an error instead of continuing.
In nearly all of these calls we have a policy attached, that is being
type verified during nla_parse_nested(), which we would miss checking
for otherwise.
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Fix broken incomplete object dumping if the list of objects does not
fit into one single netlink message.
Reported-by: Gabriel Lazar <Gabriel.Lazar@com.utcluj.ro>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Chen Gang reports:
the length of nla_data(cda[CTA_TIMEOUT_NAME]) is not limited in server side.
And indeed, its used to strcpy to a fixed-sized buffer.
Fortunately, nfnetlink users need CAP_NET_ADMIN.
Reported-by: Chen Gang <gang.chen@asianux.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
It is a frequent mistake to confuse the netlink port identifier with a
process identifier. Try to reduce this confusion by renaming fields
that hold port identifiers portid instead of pid.
I have carefully avoided changing the structures exported to
userspace to avoid changing the userspace API.
I have successfully built an allyesconfig kernel with this change.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Acked-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds namespace support for cttimeout.
Acked-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
These macros contain a hidden goto, and are thus extremely error
prone and make code hard to audit.
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch introduces nf_conntrack_l4proto_find_get() and
nf_conntrack_l4proto_put() to fix module dependencies between
timeout objects and l4-protocol conntrack modules.
Thus, we make sure that the module cannot be removed if it is
used by any of the cttimeout objects.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This patch allows you to attach the timeout policy via the
CT target, it adds a new revision of the target to ensure
backward compatibility. Moreover, it also contains the glue
code to stick the timeout object defined via nfnetlink_cttimeout
to the given flow.
Example usage (it requires installing the nfct tool and
libnetfilter_cttimeout):
1) create the timeout policy:
nfct timeout add tcp-policy0 inet tcp \
established 1000 close 10 time_wait 10 last_ack 10
2) attach the timeout policy to the packet:
iptables -I PREROUTING -t raw -p tcp -j CT --timeout tcp-policy0
You have to install the following user-space software:
a) libnetfilter_cttimeout:
git://git.netfilter.org/libnetfilter_cttimeout
b) nfct:
git://git.netfilter.org/nfct
You also have to get iptables with -j CT --timeout support.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This patch adds the timeout extension, which allows you to attach
specific timeout policies to flows.
This extension is only used by the template conntrack.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This patch adds the infrastructure to add fine timeout tuning
over nfnetlink. Now you can use the NFNL_SUBSYS_CTNETLINK_TIMEOUT
subsystem to create/delete/dump timeout objects that contain some
specific timeout policy for one flow.
The follow up patches will allow you attach timeout policy object
to conntrack via the CT target and the conntrack extension
infrastructure.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>