linux-stable.git/net/netfilter, branch v3.2.96

netfilter: xt_socket: fix compilation warnings with gcc 4.7

2017-11-11T13:34:44+00:00

commit 6703aa74ad1ba2e598bb49a37f7518da1195bacb upstream.

This patch fixes compilation warnings in xt_socket with gcc-4.7.

In file included from net/netfilter/xt_socket.c:22:0:
net/netfilter/xt_socket.c: In function ‘socket_mt6_v1’:
include/net/netfilter/nf_tproxy_core.h:175:23: warning: ‘sport’ may be used uninitialized in this function [-Wmaybe-uninitialized]
net/netfilter/xt_socket.c:265:16: note: ‘sport’ was declared here
In file included from net/netfilter/xt_socket.c:22:0:
include/net/netfilter/nf_tproxy_core.h:175:23: warning: ‘dport’ may be used uninitialized in this function [-Wmaybe-uninitialized]
net/netfilter/xt_socket.c:265:9: note: ‘dport’ was declared here
In file included from net/netfilter/xt_socket.c:22:0:
include/net/netfilter/nf_tproxy_core.h:175:6: warning: ‘saddr’ may be used uninitialized in this function [-Wmaybe-uninitialized]
net/netfilter/xt_socket.c:264:27: note: ‘saddr’ was declared here
In file included from net/netfilter/xt_socket.c:22:0:
include/net/netfilter/nf_tproxy_core.h:175:6: warning: ‘daddr’ may be used uninitialized in this function [-Wmaybe-uninitialized]
net/netfilter/xt_socket.c:264:19: note: ‘daddr’ was declared here
In file included from net/netfilter/xt_socket.c:22:0:
net/netfilter/xt_socket.c: In function ‘socket_match.isra.4’:
include/net/netfilter/nf_tproxy_core.h:75:2: warning: ‘protocol’ may be used uninitialized in this function [-Wmaybe-uninitialized]
net/netfilter/xt_socket.c:113:5: note: ‘protocol’ was declared here
In file included from include/net/tcp.h:37:0,
                 from net/netfilter/xt_socket.c:17:
include/net/inet_hashtables.h:356:45: warning: ‘sport’ may be used uninitialized in this function [-Wmaybe-uninitialized]
net/netfilter/xt_socket.c:112:16: note: ‘sport’ was declared here
In file included from net/netfilter/xt_socket.c:22:0:
include/net/netfilter/nf_tproxy_core.h:106:23: warning: ‘dport’ may be used uninitialized in this function [-Wmaybe-uninitialized]
net/netfilter/xt_socket.c:112:9: note: ‘dport’ was declared here
In file included from include/net/tcp.h:37:0,
                 from net/netfilter/xt_socket.c:17:
include/net/inet_hashtables.h:356:15: warning: ‘saddr’ may be used uninitialized in this function [-Wmaybe-uninitialized]
net/netfilter/xt_socket.c:111:16: note: ‘saddr’ was declared here
In file included from include/net/tcp.h:37:0,
                 from net/netfilter/xt_socket.c:17:
include/net/inet_hashtables.h:356:15: warning: ‘daddr’ may be used uninitialized in this function [-Wmaybe-uninitialized]
net/netfilter/xt_socket.c:111:9: note: ‘daddr’ was declared here
In file included from net/netfilter/xt_socket.c:22:0:
net/netfilter/xt_socket.c: In function ‘socket_mt6_v1’:
include/net/netfilter/nf_tproxy_core.h:175:23: warning: ‘sport’ may be used uninitialized in this function [-Wmaybe-uninitialized]
net/netfilter/xt_socket.c:268:16: note: ‘sport’ was declared here
In file included from net/netfilter/xt_socket.c:22:0:
include/net/netfilter/nf_tproxy_core.h:175:23: warning: ‘dport’ may be used uninitialized in this function [-Wmaybe-uninitialized]
net/netfilter/xt_socket.c:268:9: note: ‘dport’ was declared here
In file included from net/netfilter/xt_socket.c:22:0:
include/net/netfilter/nf_tproxy_core.h:175:6: warning: ‘saddr’ may be used uninitialized in this function [-Wmaybe-uninitialized]
net/netfilter/xt_socket.c:267:27: note: ‘saddr’ was declared here
In file included from net/netfilter/xt_socket.c:22:0:
include/net/netfilter/nf_tproxy_core.h:175:6: warning: ‘daddr’ may be used uninitialized in this function [-Wmaybe-uninitialized]
net/netfilter/xt_socket.c:267:19: note: ‘daddr’ was declared here

Signed-off-by: Pablo Neira Ayuso 
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings

ipv6: Add rt6_get_cookie() function

2017-11-11T13:34:32+00:00

commit b197df4f0f3782782e9ea8996e91b65ae33e8dd9 upstream.

Instead of doing the rt6->rt6i_node check whenever we need
to get the route's cookie.  Refactor it into rt6_get_cookie().
It is a prep work to handle FLOWI_FLAG_KNOWN_NH and also
percpu rt6_info later.

Signed-off-by: Martin KaFai Lau 
Cc: Hannes Frederic Sowa 
Cc: Steffen Klassert 
Cc: Julian Anastasov 
Signed-off-by: David S. Miller 
[bwh: Backported to 3.2:
 - Drop changes in inet6_sk_rx_dst_set(), sctp_v6_get_dst()
 - Adjust context]
Signed-off-by: Ben Hutchings

netfilter: nf_conntrack: fix RCU race in nf_conntrack_find_get

2017-10-12T14:27:21+00:00

commit c6825c0976fa7893692e0e43b09740b419b23c09 upstream.

Lets look at destroy_conntrack:

hlist_nulls_del_rcu(&ct->tuplehash[IP_CT_DIR_ORIGINAL].hnnode);
...
nf_conntrack_free(ct)
	kmem_cache_free(net->ct.nf_conntrack_cachep, ct);

net->ct.nf_conntrack_cachep is created with SLAB_DESTROY_BY_RCU.

The hash is protected by rcu, so readers look up conntracks without
locks.
A conntrack is removed from the hash, but in this moment a few readers
still can use the conntrack. Then this conntrack is released and another
thread creates conntrack with the same address and the equal tuple.
After this a reader starts to validate the conntrack:
* It's not dying, because a new conntrack was created
* nf_ct_tuple_equal() returns true.

But this conntrack is not initialized yet, so it can not be used by two
threads concurrently. In this case BUG_ON may be triggered from
nf_nat_setup_info().

Florian Westphal suggested to check the confirm bit too. I think it's
right.

task 1			task 2			task 3
			nf_conntrack_find_get
			 ____nf_conntrack_find
destroy_conntrack
 hlist_nulls_del_rcu
 nf_conntrack_free
 kmem_cache_free
						__nf_conntrack_alloc
						 kmem_cache_alloc
						 memset(&ct->tuplehash[IP_CT_DIR_MAX],
			 if (nf_ct_is_dying(ct))
			 if (!nf_ct_tuple_equal()

I'm not sure, that I have ever seen this race condition in a real life.
Currently we are investigating a bug, which is reproduced on a few nodes.
In our case one conntrack is initialized from a few tasks concurrently,
we don't have any other explanation for this.

<2>[46267.083061] kernel BUG at net/ipv4/netfilter/nf_nat_core.c:322!
...
<4>[46267.083951] RIP: 0010:[]  [] nf_nat_setup_info+0x564/0x590 [nf_nat]
...
<4>[46267.085549] Call Trace:
<4>[46267.085622]  [] alloc_null_binding+0x5b/0xa0 [iptable_nat]
<4>[46267.085697]  [] nf_nat_rule_find+0x5c/0x80 [iptable_nat]
<4>[46267.085770]  [] nf_nat_fn+0x111/0x260 [iptable_nat]
<4>[46267.085843]  [] nf_nat_out+0x48/0xd0 [iptable_nat]
<4>[46267.085919]  [] nf_iterate+0x69/0xb0
<4>[46267.085991]  [] ? ip_finish_output+0x0/0x2f0
<4>[46267.086063]  [] nf_hook_slow+0x74/0x110
<4>[46267.086133]  [] ? ip_finish_output+0x0/0x2f0
<4>[46267.086207]  [] ? dst_output+0x0/0x20
<4>[46267.086277]  [] ip_output+0xa4/0xc0
<4>[46267.086346]  [] raw_sendmsg+0x8b4/0x910
<4>[46267.086419]  [] inet_sendmsg+0x4a/0xb0
<4>[46267.086491]  [] ? sock_update_classid+0x3a/0x50
<4>[46267.086562]  [] sock_sendmsg+0x117/0x140
<4>[46267.086638]  [] ? _spin_unlock_bh+0x1b/0x20
<4>[46267.086712]  [] ? autoremove_wake_function+0x0/0x40
<4>[46267.086785]  [] ? do_ip_setsockopt+0x90/0xd80
<4>[46267.086858]  [] ? call_function_interrupt+0xe/0x20
<4>[46267.086936]  [] ? ub_slab_ptr+0x20/0x90
<4>[46267.087006]  [] ? ub_slab_ptr+0x20/0x90
<4>[46267.087081]  [] ? kmem_cache_alloc+0xd8/0x1e0
<4>[46267.087151]  [] sys_sendto+0x139/0x190
<4>[46267.087229]  [] ? sock_setsockopt+0x16d/0x6f0
<4>[46267.087303]  [] ? audit_syscall_entry+0x1d7/0x200
<4>[46267.087378]  [] ? __audit_syscall_exit+0x265/0x290
<4>[46267.087454]  [] ? compat_sys_setsockopt+0x75/0x210
<4>[46267.087531]  [] compat_sys_socketcall+0x13f/0x210
<4>[46267.087607]  [] ia32_sysret+0x0/0x5
<4>[46267.087676] Code: 91 20 e2 01 75 29 48 89 de 4c 89 f7 e8 56 fa ff ff 85 c0 0f 84 68 fc ff ff 0f b6 4d c6 41 8b 45 00 e9 4d fb ff ff e8 7c 19 e9 e0 <0f> 0b eb fe f6 05 17 91 20 e2 80 74 ce 80 3d 5f 2e 00 00 00 74
<1>[46267.088023] RIP  [] nf_nat_setup_info+0x564/0x590

Cc: Eric Dumazet 
Cc: Florian Westphal 
Cc: Pablo Neira Ayuso 
Cc: Patrick McHardy 
Cc: Jozsef Kadlecsik 
Cc: "David S. Miller" 
Cc: Cyrill Gorcunov 
Signed-off-by: Andrey Vagin 
Acked-by: Eric Dumazet 
Signed-off-by: Pablo Neira Ayuso 
Signed-off-by: Ben Hutchings

netfilter: ctnetlink: fix incorrect nf_ct_put during hash resize

2017-09-15T17:30:48+00:00

commit fefa92679dbe0c613e62b6c27235dcfbe9640ad1 upstream.

If nf_conntrack_htable_size was adjusted by the user during the ct
dump operation, we may invoke nf_ct_put twice for the same ct, i.e.
the "last" ct. This will cause the ct will be freed but still linked
in hash buckets.

It's very easy to reproduce the problem by the following commands:
  # while : ; do
  echo $RANDOM > /proc/sys/net/netfilter/nf_conntrack_buckets
  done
  # while : ; do
  conntrack -L
  done
  # iperf -s 127.0.0.1 &
  # iperf -c 127.0.0.1 -P 60 -t 36000

After a while, the system will hang like this:
  NMI watchdog: BUG: soft lockup - CPU#1 stuck for 22s! [bash:20184]
  NMI watchdog: BUG: soft lockup - CPU#0 stuck for 22s! [iperf:20382]
  ...

So at last if we find cb->args[1] is equal to "last", this means hash
resize happened, then we can set cb->args[1] to 0 to fix the above
issue.

Fixes: d205dc40798d ("[NETFILTER]: ctnetlink: fix deadlock in table dumping")
Signed-off-by: Liping Zhang 
Signed-off-by: Pablo Neira Ayuso 
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings

netfilter: ctnetlink: make it safer when updating ct->status

2017-08-26T01:14:03+00:00

commit 53b56da83d7899de375a9de153fd7f5397de85e6 upstream.

After converting to use rcu for conntrack hash, one CPU may update
the ct->status via ctnetlink, while another CPU may process the
packets and update the ct->status.

So the non-atomic operation "ct->status |= status;" via ctnetlink
becomes unsafe, and this may clear the IPS_DYING_BIT bit set by
another CPU unexpectedly. For example:
         CPU0                            CPU1
  ctnetlink_change_status        __nf_conntrack_find_get
      old = ct->status              nf_ct_gc_expired
          -                         nf_ct_kill
          -                      test_and_set_bit(IPS_DYING_BIT
      new = old | status;                 -
  ct->status = new; <-- oops, _DYING_ is cleared!

Now using a series of atomic bit operation to solve the above issue.

Also note, user shouldn't set IPS_TEMPLATE, IPS_SEQ_ADJUST directly,
so make these two bits be unchangable too.

If we set the IPS_TEMPLATE_BIT, ct will be freed by nf_ct_tmpl_free,
but actually it is alloced by nf_conntrack_alloc.
If we set the IPS_SEQ_ADJUST_BIT, this may cause the NULL pointer
deference, as the nfct_seqadj(ct) maybe NULL.

Last, add some comments to describe the logic change due to the
commit a963d710f367 ("netfilter: ctnetlink: Fix regression in CTA_STATUS
processing"), which makes me feel a little confusing.

Fixes: 76507f69c44e ("[NETFILTER]: nf_conntrack: use RCU for conntrack hash")
Signed-off-by: Liping Zhang 
Signed-off-by: Pablo Neira Ayuso 
[bwh: Backported to 3.2:
 - IPS_UNCHANGEABLE_MASK was not previously defined and ctnetlink_update_status()
   is not needed
 - enum ip_conntrack_status only assigns 13 bits
 - Adjust filename]
Signed-off-by: Ben Hutchings

netfilter: nf_conntrack_sip: extend request line validation

2017-02-23T03:50:56+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 
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings

netfilter: restart search if moved to other chain

2017-02-23T03:50:48+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 
[bwh: Backported to 3.2:
 - Adjust context
 - Use NF_CT_STAT_INC(), not the _ATOMIC variant, since we disable BHs]
Signed-off-by: Ben Hutchings

netfilter: nfnetlink_queue: reject verdict request from different portid

2016-11-20T01:01:31+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 
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings

nf_conntrack: avoid kernel pointer value leak in slab name

2016-06-15T20:28:14+00:00

commit 31b0b385f69d8d5491a4bca288e25e63f1d945d0 upstream.

The slab name ends up being visible in the directory structure under
/sys, and even if you don't have access rights to the file you can see
the filenames.

Just use a 64-bit counter instead of the pointer to the 'net' structure
to generate a unique name.

This code will go away in 4.7 when the conntrack code moves to a single
kmemcache, but this is the backportable simple solution to avoiding
leaking kernel pointers to user space.

Fixes: 5b3501faa874 ("netfilter: nf_conntrack: per netns nf_conntrack_cachep")
Signed-off-by: Linus Torvalds 
Acked-by: Eric Dumazet 
Signed-off-by: David S. Miller 
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings

ipvs: correct initial offset of Call-ID header search in SIP persistence engine

2016-04-30T22:05:16+00:00

commit 7617a24f83b5d67f4dab1844956be1cebc44aec8 upstream.

The IPVS SIP persistence engine is not able to parse the SIP header
"Call-ID" when such header is inserted in the first positions of
the SIP message.

When IPVS is configured with "--pe sip" option, like for example:
ipvsadm -A -u 1.2.3.4:5060 -s rr --pe sip -p 120 -o
some particular messages (see below for details) do not create entries
in the connection template table, which can be listed with:
ipvsadm -Lcn --persistent-conn

Problematic SIP messages are SIP responses having "Call-ID" header
positioned just after message first line:
SIP/2.0 200 OK
[Call-ID header here]
[rest of the headers]

When "Call-ID" header is positioned down (after a few other headers)
it is correctly recognized.

This is due to the data offset used in get_callid function call inside
ip_vs_pe_sip.c file: since dptr already points to the start of the
SIP message, the value of dataoff should be initially 0.
Otherwise the header is searched starting from some bytes after the
first character of the SIP message.

Fixes: 758ff0338722 ("IPVS: sip persistence engine")
Signed-off-by: Marco Angaroni 
Acked-by: Julian Anastasov 
Signed-off-by: Simon Horman 
Signed-off-by: Ben Hutchings