linux-stable.git/net/netfilter, branch v4.4.115

netfilter: xt_osf: Add missing permission checks

2018-01-31T11:06:11+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

2018-01-31T11:06:11+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

2018-01-31T11:06:10+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

2018-01-31T11:06:10+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: nfnetlink_queue: reject verdict request from different portid

2018-01-31T11:06:10+00:00

commit 00a3101f561816e58de054a470484996f78eb5eb upstream.

Like NFQNL_MSG_VERDICT_BATCH do, we should also reject the verdict
request when the portid is not same with the initial portid(maybe
from another process).

Fixes: 97d32cf9440d ("netfilter: nfnetlink_queue: batch verdict support")
Signed-off-by: Liping Zhang 
Reviewed-by: Florian Westphal 
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

2018-01-31T11:06:10+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: x_tables: speed up jump target validation

2018-01-31T11:06:10+00:00

commit f4dc77713f8016d2e8a3295e1c9c53a21f296def upstream.

The dummy ruleset I used to test the original validation change was broken,
most rules were unreachable and were not tested by mark_source_chains().

In some cases rulesets that used to load in a few seconds now require
several minutes.

sample ruleset that shows the behaviour:

echo "*filter"
for i in $(seq 0 100000);do
        printf ":chain_%06x - [0:0]\n" $i
done
for i in $(seq 0 100000);do
   printf -- "-A INPUT -j chain_%06x\n" $i
   printf -- "-A INPUT -j chain_%06x\n" $i
   printf -- "-A INPUT -j chain_%06x\n" $i
done
echo COMMIT

[ pipe result into iptables-restore ]

This ruleset will be about 74mbyte in size, with ~500k searches
though all 500k[1] rule entries. iptables-restore will take forever
(gave up after 10 minutes)

Instead of always searching the entire blob for a match, fill an
array with the start offsets of every single ipt_entry struct,
then do a binary search to check if the jump target is present or not.

After this change ruleset restore times get again close to what one
gets when reverting 36472341017529e (~3 seconds on my workstation).

[1] every user-defined rule gets an implicit RETURN, so we get
300k jumps + 100k userchains + 100k returns -> 500k rule entries

Fixes: 36472341017529e ("netfilter: x_tables: validate targets of jumps")
Reported-by: Jeff Wu 
Tested-by: Jeff Wu 
Signed-off-by: Florian Westphal 
Signed-off-by: Pablo Neira Ayuso 
Acked-by: Michal Kubecek 
Signed-off-by: Greg Kroah-Hartman

netfilter: nfnetlink_queue: fix secctx memory leak

2017-12-25T13:22:13+00:00

[ Upstream commit 77c1c03c5b8ef28e55bb0aff29b1e006037ca645 ]

We must call security_release_secctx to free the memory returned by
security_secid_to_secctx, otherwise memory may be leaked forever.

Fixes: ef493bd930ae ("netfilter: nfnetlink_queue: add security context information")
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 a race when walk the nf_ct_helper_hash table

2017-12-25T13:22:12+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

2017-12-25T13:22:11+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