linux-stable.git/net/netfilter, branch v3.18.95

netfilter: xt_osf: Add missing permission checks

2018-01-31T13:46:14+00:00

commit 916a27901de01446bcf57ecca4783f6cff493309 upstream.

The capability check in nfnetlink_rcv() verifies that the caller
has CAP_NET_ADMIN in the namespace that "owns" the netlink socket.
However, xt_osf_fingers is shared by all net namespaces on the
system.  An unprivileged user can create user and net namespaces
in which he holds CAP_NET_ADMIN to bypass the netlink_net_capable()
check:

    vpnns -- nfnl_osf -f /tmp/pf.os

    vpnns -- nfnl_osf -f /tmp/pf.os -d

These non-root operations successfully modify the systemwide OS
fingerprint list.  Add new capable() checks so that they can't.

Signed-off-by: Kevin Cernekee 
Signed-off-by: Pablo Neira Ayuso 
Acked-by: Michal Kubecek 
Signed-off-by: Greg Kroah-Hartman

netfilter: nfnetlink_cthelper: Add missing permission checks

2018-01-31T13:46:14+00:00

commit 4b380c42f7d00a395feede754f0bc2292eebe6e5 upstream.

The capability check in nfnetlink_rcv() verifies that the caller
has CAP_NET_ADMIN in the namespace that "owns" the netlink socket.
However, nfnl_cthelper_list is shared by all net namespaces on the
system.  An unprivileged user can create user and net namespaces
in which he holds CAP_NET_ADMIN to bypass the netlink_net_capable()
check:

    $ nfct helper list
    nfct v1.4.4: netlink error: Operation not permitted
    $ vpnns -- nfct helper list
    {
            .name = ftp,
            .queuenum = 0,
            .l3protonum = 2,
            .l4protonum = 6,
            .priv_data_len = 24,
            .status = enabled,
    };

Add capable() checks in nfnetlink_cthelper, as this is cleaner than
trying to generalize the solution.

Signed-off-by: Kevin Cernekee 
Signed-off-by: Pablo Neira Ayuso 
Acked-by: Michal Kubecek 
Signed-off-by: Greg Kroah-Hartman

netfilter: nf_conntrack_sip: extend request line validation

2018-01-31T13:46:13+00:00

commit 444f901742d054a4cd5ff045871eac5131646cfb upstream.

on SIP requests, so a fragmented TCP SIP packet from an allow header starting with
 INVITE,NOTIFY,OPTIONS,REFER,REGISTER,UPDATE,SUBSCRIBE
 Content-Length: 0

will not bet interpreted as an INVITE request. Also Request-URI must start with an alphabetic character.

Confirm with RFC 3261
 Request-Line   =  Method SP Request-URI SP SIP-Version CRLF

Fixes: 30f33e6dee80 ("[NETFILTER]: nf_conntrack_sip: support method specific request/response handling")
Signed-off-by: Ulrich Weber 
Acked-by: Marco Angaroni 
Signed-off-by: Pablo Neira Ayuso 
Acked-by: Michal Kubecek 
Signed-off-by: Greg Kroah-Hartman

netfilter: restart search if moved to other chain

2018-01-31T13:46:13+00:00

commit 95a8d19f28e6b29377a880c6264391a62e07fccc upstream.

In case nf_conntrack_tuple_taken did not find a conflicting entry
check that all entries in this hash slot were tested and restart
in case an entry was moved to another chain.

Reported-by: Eric Dumazet 
Fixes: ea781f197d6a ("netfilter: nf_conntrack: use SLAB_DESTROY_BY_RCU and get rid of call_rcu()")
Signed-off-by: Florian Westphal 
Acked-by: Eric Dumazet 
Signed-off-by: Pablo Neira Ayuso 
Acked-by: Michal Kubecek 
Signed-off-by: Greg Kroah-Hartman

netfilter: nf_ct_expect: remove the redundant slash when policy name is empty

2018-01-31T13:46:13+00:00

commit b173a28f62cf929324a8a6adcc45adadce311d16 upstream.

The 'name' filed in struct nf_conntrack_expect_policy{} is not a
pointer, so check it is NULL or not will always return true. Even if the
name is empty, slash will always be displayed like follows:
  # cat /proc/net/nf_conntrack_expect
  297 l3proto = 2 proto=6 src=1.1.1.1 dst=2.2.2.2 sport=1 dport=1025 ftp/
                                                                        ^

Fixes: 3a8fc53a45c4 ("netfilter: nf_ct_helper: allocate 16 bytes for the helper and policy names")
Signed-off-by: Liping Zhang 
Signed-off-by: Pablo Neira Ayuso 
Acked-by: Michal Kubecek 
Signed-off-by: Greg Kroah-Hartman

netfilter: nfnl_cthelper: fix a race when walk the nf_ct_helper_hash table

2017-12-25T13:20:08+00:00

[ Upstream commit 83d90219a5df8d950855ce73229a97b63605c317 ]

The nf_ct_helper_hash table is protected by nf_ct_helper_mutex, while
nfct_helper operation is protected by nfnl_lock(NFNL_SUBSYS_CTHELPER).
So it's possible that one CPU is walking the nf_ct_helper_hash for
cthelper add/get/del, another cpu is doing nf_conntrack_helpers_unregister
at the same time. This is dangrous, and may cause use after free error.

Note, delete operation will flush all cthelpers added via nfnetlink, so
using rcu to do protect is not easy.

Now introduce a dummy list to record all the cthelpers added via
nfnetlink, then we can walk the dummy list instead of walking the
nf_ct_helper_hash. Also, keep nfnl_cthelper_dump_table unchanged, it
may be invoked without nfnl_lock(NFNL_SUBSYS_CTHELPER) held.

Signed-off-by: Liping Zhang 
Signed-off-by: Pablo Neira Ayuso 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

netfilter: nfnl_cthelper: Fix memory leak

2017-12-25T13:20:07+00:00

[ Upstream commit f83bf8da1135ca635aac8f062cad3f001fcf3a26 ]

We have memory leaks of nf_conntrack_helper & expect_policy.

Signed-off-by: Jeffy Chen 
Signed-off-by: Pablo Neira Ayuso 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

netfilter: nfnl_cthelper: fix runtime expectation policy updates

2017-12-25T13:20:06+00:00

[ Upstream commit 2c422257550f123049552b39f7af6e3428a60f43 ]

We only allow runtime updates of expectation policies for timeout and
maximum number of expectations, otherwise reject the update.

Signed-off-by: Pablo Neira Ayuso 
Acked-by: Liping Zhang 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

netfilter: nf_tables: fix oob access

2017-11-30T08:35:55+00:00

[ Upstream commit 3e38df136e453aa69eb4472108ebce2fb00b1ba6 ]

BUG: KASAN: slab-out-of-bounds in nf_tables_rule_destroy+0xf1/0x130 at addr ffff88006a4c35c8
Read of size 8 by task nft/1607

When we've destroyed last valid expr, nft_expr_next() returns an invalid expr.
We must not dereference it unless it passes != nft_expr_last() check.

Signed-off-by: Florian Westphal 
Signed-off-by: Pablo Neira Ayuso 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

netfilter: nft_queue: use raw_smp_processor_id()

2017-11-30T08:35:55+00:00

[ Upstream commit c2e756ff9e699865d294cdc112acfc36419cf5cc ]

Using smp_processor_id() causes splats with PREEMPT_RCU:

[19379.552780] BUG: using smp_processor_id() in preemptible [00000000] code: ping/32389
[19379.552793] caller is debug_smp_processor_id+0x17/0x19
[...]
[19379.552823] Call Trace:
[19379.552832]  [] dump_stack+0x67/0x90
[19379.552837]  [] check_preemption_disabled+0xe5/0xf5
[19379.552842]  [] debug_smp_processor_id+0x17/0x19
[19379.552849]  [] nft_queue_eval+0x35/0x20c [nft_queue]

No need to disable preemption since we only fetch the numeric value, so
let's use raw_smp_processor_id() instead.

Signed-off-by: Pablo Neira Ayuso 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman