linux.git/net/ipv4/netfilter, branch v4.6-rc2

netfilter: ipv4: fix NULL dereference

2016-03-28T15:59:29+00:00

Commit fa50d974d104 ("ipv4: Namespaceify ip_default_ttl sysctl knob")
use sock_net(skb->sk) to get the net namespace, but we can't assume
that sk_buff->sk is always exist, so when it is NULL, oops will happen.

Signed-off-by: Liping Zhang 
Reviewed-by: Nikolay Borisov 
Signed-off-by: Pablo Neira Ayuso

netfilter: x_tables: enforce nul-terminated table name from getsockopt GET_ENTRIES

2016-03-28T15:59:24+00:00

Make sure the table names via getsockopt GET_ENTRIES is nul-terminated
in ebtables and all the x_tables variants and their respective compat
code. Uncovered by KASAN.

Reported-by: Baozeng Ding 
Signed-off-by: Pablo Neira Ayuso

netfilter: x_tables: fix unconditional helper

2016-03-28T15:59:15+00:00

Ben Hawkes says:

 In the mark_source_chains function (net/ipv4/netfilter/ip_tables.c) it
 is possible for a user-supplied ipt_entry structure to have a large
 next_offset field. This field is not bounds checked prior to writing a
 counter value at the supplied offset.

Problem is that mark_source_chains should not have been called --
the rule doesn't have a next entry, so its supposed to return
an absolute verdict of either ACCEPT or DROP.

However, the function conditional() doesn't work as the name implies.
It only checks that the rule is using wildcard address matching.

However, an unconditional rule must also not be using any matches
(no -m args).

The underflow validator only checked the addresses, therefore
passing the 'unconditional absolute verdict' test, while
mark_source_chains also tested for presence of matches, and thus
proceeeded to the next (not-existent) rule.

Unify this so that all the callers have same idea of 'unconditional rule'.

Reported-by: Ben Hawkes 
Signed-off-by: Florian Westphal 
Signed-off-by: Pablo Neira Ayuso

netfilter: x_tables: make sure e->next_offset covers remaining blob size

2016-03-28T15:59:08+00:00

Otherwise this function may read data beyond the ruleset blob.

Signed-off-by: Florian Westphal 
Signed-off-by: Pablo Neira Ayuso

netfilter: x_tables: validate e->target_offset early

2016-03-28T15:59:04+00:00

We should check that e->target_offset is sane before
mark_source_chains gets called since it will fetch the target entry
for loop detection.

Signed-off-by: Florian Westphal 
Signed-off-by: Pablo Neira Ayuso

Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-next

2016-03-15T02:10:25+00:00

Pablo Neira Ayuso says:

====================
Netfilter/IPVS/OVS updates for net-next

The following patchset contains Netfilter/IPVS fixes and OVS NAT
support, more specifically this batch is composed of:

1) Fix a crash in ipset when performing a parallel flush/dump with
   set:list type, from Jozsef Kadlecsik.

2) Make sure NFACCT_FILTER_* netlink attributes are in place before
   accessing them, from Phil Turnbull.

3) Check return error code from ip_vs_fill_iph_skb_off() in IPVS SIP
   helper, from Arnd Bergmann.

4) Add workaround to IPVS to reschedule existing connections to new
   destination server by dropping the packet and wait for retransmission
   of TCP syn packet, from Julian Anastasov.

5) Allow connection rescheduling in IPVS when in CLOSE state, also
   from Julian.

6) Fix wrong offset of SIP Call-ID in IPVS helper, from Marco Angaroni.

7) Validate IPSET_ATTR_ETHER netlink attribute length, from Jozsef.

8) Check match/targetinfo netlink attribute size in nft_compat,
   patch from Florian Westphal.

9) Check for integer overflow on 32-bit systems in x_tables, from
   Florian Westphal.

Several patches from Jarno Rajahalme to prepare the introduction of
NAT support to OVS based on the Netfilter infrastructure:

10) Schedule IP_CT_NEW_REPLY definition for removal in
    nf_conntrack_common.h.

11) Simplify checksumming recalculation in nf_nat.

12) Add comments to the openvswitch conntrack code, from Jarno.

13) Update the CT state key only after successful nf_conntrack_in()
    invocation.

14) Find existing conntrack entry after upcall.

15) Handle NF_REPEAT case due to templates in nf_conntrack_in().

16) Call the conntrack helper functions once the conntrack has been
    confirmed.

17) And finally, add the NAT interface to OVS.

The batch closes with:

18) Cleanup to use spin_unlock_wait() instead of
    spin_lock()/spin_unlock(), from Nicholas Mc Guire.
====================

Signed-off-by: David S. Miller

netfilter: Allow calling into nat helper without skb_dst.

2016-03-14T22:47:27+00:00

NAT checksum recalculation code assumes existence of skb_dst, which
becomes a problem for a later patch in the series ("openvswitch:
Interface with NAT.").  Simplify this by removing the check on
skb_dst, as the checksum will be dealt with later in the stack.

Suggested-by: Pravin Shelar 
Signed-off-by: Jarno Rajahalme 
Signed-off-by: Pablo Neira Ayuso

ipv4: Don't do expensive useless work during inetdev destroy.

2016-03-14T03:28:35+00:00

When an inetdev is destroyed, every address assigned to the interface
is removed.  And in this scenerio we do two pointless things which can
be very expensive if the number of assigned interfaces is large:

1) Address promotion.  We are deleting all addresses, so there is no
   point in doing this.

2) A full nf conntrack table purge for every address.  We only need to
   do this once, as is already caught by the existing
   masq_dev_notifier so masq_inet_event() can skip this.

Reported-by: Solar Designer 
Signed-off-by: David S. Miller 
Tested-by: Cyrill Gorcunov

netfilter: nft_masq: support port range

2016-03-02T19:05:27+00:00

Complete masquerading support by allowing port range selection.

Signed-off-by: Pablo Neira Ayuso

netfilter: xtables: don't hook tables by default

2016-03-02T19:05:24+00:00

delay hook registration until the table is being requested inside a
namespace.

Historically, a particular table (iptables mangle, ip6tables filter, etc)
was registered on module load.

When netns support was added to iptables only the ip/ip6tables ruleset was
made namespace aware, not the actual hook points.

This means f.e. that when ipt_filter table/module is loaded on a system,
then each namespace on that system has an (empty) iptables filter ruleset.

In other words, if a namespace sends a packet, such skb is 'caught' by
netfilter machinery and fed to hooking points for that table (i.e. INPUT,
FORWARD, etc).

Thanks to Eric Biederman, hooks are no longer global, but per namespace.

This means that we can avoid allocation of empty ruleset in a namespace and
defer hook registration until we need the functionality.

We register a tables hook entry points ONLY in the initial namespace.
When an iptables get/setockopt is issued inside a given namespace, we check
if the table is found in the per-namespace list.

If not, we attempt to find it in the initial namespace, and, if found,
create an empty default table in the requesting namespace and register the
needed hooks.

Hook points are destroyed only once namespace is deleted, there is no
'usage count' (it makes no sense since there is no 'remove table' operation
in xtables api).

Signed-off-by: Florian Westphal 
Signed-off-by: Pablo Neira Ayuso