Commit Graph

7987 Commits

Author SHA1 Message Date
Steffen Klassert
9b83e03198 ipv4: Don't pass IP fragments to upper layer GRO handlers.
Upper layer GRO handlers can not handle IP fragments, so
exit GRO processing in this case.

This fixes ESP GRO because the packet must be reassembled
before we can decapsulate, otherwise we get authentication
failures.

It also aligns IPv4 to IPv6 where packets with fragmentation
headers are not passed to upper layer GRO handlers.

Fixes: 7785bba299 ("esp: Add a software GRO codepath")
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-28 16:00:38 -04:00
Wei Wang
c120144407 tcp: memset ca_priv data to 0 properly
Always zero out ca_priv data in tcp_assign_congestion_control() so that
ca_priv data is cleared out during socket creation.
Also always zero out ca_priv data in tcp_reinit_congestion_control() so
that when cc algorithm is changed, ca_priv data is cleared out as well.
We should still zero out ca_priv data even in TCP_CLOSE state because
user could call connect() on AF_UNSPEC to disconnect the socket and
leave it in TCP_CLOSE state and later call setsockopt() to switch cc
algorithm on this socket.

Fixes: 2b0a8c9ee ("tcp: add CDG congestion control")
Reported-by: Andrey Konovalov  <andreyknvl@google.com>
Signed-off-by: Wei Wang <weiwan@google.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Acked-by: Yuchung Cheng <ycheng@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-26 14:58:32 -04:00
Ansis Atteka
b40c5f4fde udp: disable inner UDP checksum offloads in IPsec case
Otherwise, UDP checksum offloads could corrupt ESP packets by attempting
to calculate UDP checksum when this inner UDP packet is already protected
by IPsec.

One way to reproduce this bug is to have a VM with virtio_net driver (UFO
set to ON in the guest VM); and then encapsulate all guest's Ethernet
frames in Geneve; and then further encrypt Geneve with IPsec.  In this
case following symptoms are observed:
1. If using ixgbe NIC, then it will complain with following error message:
   ixgbe 0000:01:00.1: partial checksum but l4 proto=32!
2. Receiving IPsec stack will drop all the corrupted ESP packets and
   increase XfrmInStateProtoError counter in /proc/net/xfrm_stat.
3. iperf UDP test from the VM with packet sizes above MTU will not work at
   all.
4. iperf TCP test from the VM will get ridiculously low performance because.

Signed-off-by: Ansis Atteka <aatteka@ovn.org>
Co-authored-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-24 13:48:54 -04:00
Robert Shearman
b7c8487cb3 ipv4: Avoid caching l3mdev dst on mismatched local route
David reported that doing the following:

    ip li add red type vrf table 10
    ip link set dev eth1 vrf red
    ip addr add 127.0.0.1/8 dev red
    ip link set dev eth1 up
    ip li set red up
    ping -c1 -w1 -I red 127.0.0.1
    ip li del red

when either policy routing IP rules are present or the local table
lookup ip rule is before the l3mdev lookup results in a hang with
these messages:

    unregister_netdevice: waiting for red to become free. Usage count = 1

The problem is caused by caching the dst used for sending the packet
out of the specified interface on a local route with a different
nexthop interface. Thus the dst could stay around until the route in
the table the lookup was done is deleted which may be never.

Address the problem by not forcing output device to be the l3mdev in
the flow's output interface if the lookup didn't use the l3mdev. This
then results in the dst using the right device according to the route.

Changes in v2:
 - make the dev_out passed in by __ip_route_output_key_hash correct
   instead of checking the nh dev if FLOWI_FLAG_SKIP_NH_OIF is set as
   suggested by David.

Fixes: 5f02ce24c2 ("net: l3mdev: Allow the l3mdev to be a loopback")
Reported-by: David Ahern <dsa@cumulusnetworks.com>
Suggested-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: Robert Shearman <rshearma@brocade.com>
Acked-by: David Ahern <dsa@cumulusnetworks.com>
Tested-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-24 12:50:29 -04:00
Willem de Bruijn
1862d6208d net-timestamp: avoid use-after-free in ip_recv_error
Syzkaller reported a use-after-free in ip_recv_error at line

    info->ipi_ifindex = skb->dev->ifindex;

This function is called on dequeue from the error queue, at which
point the device pointer may no longer be valid.

Save ifindex on enqueue in __skb_complete_tx_timestamp, when the
pointer is valid or NULL. Store it in temporary storage skb->cb.

It is safe to reference skb->dev here, as called from device drivers
or dev_queue_xmit. The exception is when called from tcp_ack_tstamp;
in that case it is NULL and ifindex is set to 0 (invalid).

Do not return a pktinfo cmsg if ifindex is 0. This maintains the
current behavior of not returning a cmsg if skb->dev was NULL.

On dequeue, the ipv4 path will cast from sock_exterr_skb to
in_pktinfo. Both have ifindex as their first element, so no explicit
conversion is needed. This is by design, introduced in commit
0b922b7a82 ("net: original ingress device index in PKTINFO"). For
ipv6 ip6_datagram_support_cmsg converts to in6_pktinfo.

Fixes: 829ae9d611 ("net-timestamp: allow reading recv cmsg on errqueue with origin tstamp")
Reported-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-17 12:59:22 -04:00
WANG Cong
1215e51eda ipv4: fix a deadlock in ip_ra_control
Similar to commit 87e9f03159
("ipv4: fix a potential deadlock in mcast getsockopt() path"),
there is a deadlock scenario for IP_ROUTER_ALERT too:

       CPU0                    CPU1
       ----                    ----
  lock(rtnl_mutex);
                               lock(sk_lock-AF_INET);
                               lock(rtnl_mutex);
  lock(sk_lock-AF_INET);

Fix this by always locking RTNL first on all setsockopt() paths.

Note, after this patch ip_ra_lock is no longer needed either.

Reported-by: Dmitry Vyukov <dvyukov@google.com>
Tested-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-17 12:46:50 -04:00
David S. Miller
f4c13c8ec5 Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf
Pablo Neira Ayuso says:

====================
Netfilter fixes for net

The following patchset contains Netfilter fixes for your net tree,
they are:

1) Missing TCP header sanity check in TCPMSS target, from Eric Dumazet.

2) Incorrect event message type for related conntracks created via
   ctnetlink, from Liping Zhang.

3) Fix incorrect rcu locking when handling helpers from ctnetlink,
   from Gao feng.

4) Fix missing rcu locking when updating helper, from Liping Zhang.

5) Fix missing read_lock_bh when iterating over list of device addresses
   from TPROXY and redirect, also from Liping.

6) Fix crash when trying to dump expectations from conntrack with no
   helper via ctnetlink, from Liping.

7) Missing RCU protection to expecation list update given ctnetlink
   iterates over the list under rcu read lock side, from Liping too.

8) Don't dump autogenerated seed in nft_hash to userspace, this is
   very confusing to the user, again from Liping.

9) Fix wrong conntrack netns module refcount in ipt_CLUSTERIP,
   from Gao feng.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-14 10:47:13 -04:00
Gao Feng
fe50543c19 netfilter: ipt_CLUSTERIP: Fix wrong conntrack netns refcnt usage
Current codes invoke wrongly nf_ct_netns_get in the destroy routine,
it should use nf_ct_netns_put, not nf_ct_netns_get.
It could cause some modules could not be unloaded.

Fixes: ecb2421b5d ("netfilter: add and use nf_ct_netns_get/put")
Signed-off-by: Gao Feng <fgao@ikuai8.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-04-13 23:21:40 +02:00
Eric Dumazet
17c3060b17 tcp: clear saved_syn in tcp_disconnect()
In the (very unlikely) case a passive socket becomes a listener,
we do not want to duplicate its saved SYN headers.

This would lead to double frees, use after free, and please hackers and
various fuzzers

Tested:
    0 socket(..., SOCK_STREAM, IPPROTO_TCP) = 3
   +0 setsockopt(3, IPPROTO_TCP, TCP_SAVE_SYN, [1], 4) = 0
   +0 fcntl(3, F_SETFL, O_RDWR|O_NONBLOCK) = 0

   +0 bind(3, ..., ...) = 0
   +0 listen(3, 5) = 0

   +0 < S 0:0(0) win 32972 <mss 1460,nop,wscale 7>
   +0 > S. 0:0(0) ack 1 <...>
  +.1 < . 1:1(0) ack 1 win 257
   +0 accept(3, ..., ...) = 4

   +0 connect(4, AF_UNSPEC, ...) = 0
   +0 close(3) = 0
   +0 bind(4, ..., ...) = 0
   +0 listen(4, 5) = 0

   +0 < S 0:0(0) win 32972 <mss 1460,nop,wscale 7>
   +0 > S. 0:0(0) ack 1 <...>
  +.1 < . 1:1(0) ack 1 win 257

Fixes: cd8ae85299 ("tcp: provide SYN headers for passive connections")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-09 18:27:28 -07:00
Gao Feng
7cc2b043bc net: tcp: Increase TCP_MIB_OUTRSTS even though fail to alloc skb
Because TCP_MIB_OUTRSTS is an important count, so always increase it
whatever send it successfully or not.

Now move the increment of TCP_MIB_OUTRSTS to the top of
tcp_send_active_reset to make sure it is increased always even though
fail to alloc skb.

Signed-off-by: Gao Feng <fgao@ikuai8.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-08 08:30:09 -07:00
Yuchung Cheng
cc663f4d4c tcp: restrict F-RTO to work-around broken middle-boxes
The recent extension of F-RTO 89fe18e44 ("tcp: extend F-RTO
to catch more spurious timeouts") interacts badly with certain
broken middle-boxes.  These broken boxes modify and falsely raise
the receive window on the ACKs. During a timeout induced recovery,
F-RTO would send new data packets to probe if the timeout is false
or not. Since the receive window is falsely raised, the receiver
would silently drop these F-RTO packets. The recovery would take N
(exponentially backoff) timeouts to repair N packet losses.  A TCP
performance killer.

Due to this unfortunate situation, this patch removes this extension
to revert F-RTO back to the RFC specification.

Fixes: 89fe18e44f ("tcp: extend F-RTO to catch more spurious timeouts")
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-07 11:44:00 -07:00
Florian Larysch
a8801799c6 net: ipv4: fix multipath RTM_GETROUTE behavior when iif is given
inet_rtm_getroute synthesizes a skeletal ICMP skb, which is passed to
ip_route_input when iif is given. If a multipath route is present for
the designated destination, ip_multipath_icmp_hash ends up being called,
which uses the source/destination addresses within the skb to calculate
a hash. However, those are not set in the synthetic skb, causing it to
return an arbitrary and incorrect result.

Instead, use UDP, which gets no such special treatment.

Signed-off-by: Florian Larysch <fl@n621.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-06 12:18:56 -07:00
Yuchung Cheng
2d2517ee31 tcp: fix reordering SNMP under-counting
Currently the reordering SNMP counters only increase if a connection
sees a higher degree then it has previously seen. It ignores if the
reordering degree is not greater than the default system threshold.
This significantly under-counts the number of reordering events
and falsely convey that reordering is rare on the network.

This patch properly and faithfully records the number of reordering
events detected by the TCP stack, just like the comment says "this
exciting event is worth to be remembered". Note that even so TCP
still under-estimate the actual reordering events because TCP
requires TS options or certain packet sequences to detect reordering
(i.e. ACKing never-retransmitted sequence in recovery or disordered
 state).

Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-05 18:41:27 -07:00
Yuchung Cheng
ecde8f36f8 tcp: fix lost retransmit SNMP under-counting
The lost retransmit SNMP stat is under-counting retransmission
that uses segment offloading. This patch fixes that so all
retransmission related SNMP counters are consistent.

Fixes: 10d3be5692 ("tcp-tso: do not split TSO packets at retransmit time")
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-05 18:41:27 -07:00
Marcelo Ricardo Leitner
0b9aefea86 tcp: minimize false-positives on TCP/GRO check
Markus Trippelsdorf reported that after commit dcb17d22e1 ("tcp: warn
on bogus MSS and try to amend it") the kernel started logging the
warning for a NIC driver that doesn't even support GRO.

It was diagnosed that it was possibly caused on connections that were
using TCP Timestamps but some packets lacked the Timestamps option. As
we reduce rcv_mss when timestamps are used, the lack of them would cause
the packets to be bigger than expected, although this is a valid case.

As this warning is more as a hint, getting a clean-cut on the
threshold is probably not worth the execution time spent on it. This
patch thus alleviates the false-positives with 2 quick checks: by
accounting for the entire TCP option space and also checking against the
interface MTU if it's available.

These changes, specially the MTU one, might mask some real positives,
though if they are really happening, it's possible that sooner or later
it will be triggered anyway.

Reported-by: Markus Trippelsdorf <markus@trippelsdorf.de>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-03 18:43:41 -07:00
David S. Miller
8f1f7eeb22 Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf
Pablo Neira Ayuso says:

====================
Netfilter fixes for net

The following patchset contains a rather large update with Netfilter
fixes, specifically targeted to incorrect RCU usage in several spots and
the userspace conntrack helper infrastructure (nfnetlink_cthelper),
more specifically they are:

1) expect_class_max is incorrect set via cthelper, as in kernel semantics
   mandate that this represents the array of expectation classes minus 1.
   Patch from Liping Zhang.

2) Expectation policy updates via cthelper are currently broken for several
   reasons: This code allows illegal changes in the policy such as changing
   the number of expeciation classes, it is leaking the updated policy and
   such update occurs with no RCU protection at all. Fix this by adding a
   new nfnl_cthelper_update_policy() that describes what is really legal on
   the update path.

3) Fix several memory leaks in cthelper, from Jeffy Chen.

4) synchronize_rcu() is missing in the removal path of several modules,
   this may lead to races since CPU may still be running on code that has
   just gone. Also from Liping Zhang.

5) Don't use the helper hashtable from cthelper, it is not safe to walk
   over those bits without the helper mutex. Fix this by introducing a
   new independent list for userspace helpers. From Liping Zhang.

6) nf_ct_extend_unregister() needs synchronize_rcu() to make sure no
   packets are walking on any conntrack extension that is gone after
   module removal, again from Liping.

7) nf_nat_snmp may crash if we fail to unregister the helper due to
   accidental leftover code, from Gao Feng.

8) Fix leak in nfnetlink_queue with secctx support, from Liping Zhang.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-29 14:35:25 -07:00
Mark Rutland
ffefb6f4d6 net: ipconfig: fix ic_close_devs() use-after-free
Our chosen ic_dev may be anywhere in our list of ic_devs, and we may
free it before attempting to close others. When we compare d->dev and
ic_dev->dev, we're potentially dereferencing memory returned to the
allocator. This causes KASAN to scream for each subsequent ic_dev we
check.

As there's a 1-1 mapping between ic_devs and netdevs, we can instead
compare d and ic_dev directly, which implicitly handles the !ic_dev
case, and avoids the use-after-free. The ic_dev pointer may be stale,
but we will not dereference it.

Original splat:

[    6.487446] ==================================================================
[    6.494693] BUG: KASAN: use-after-free in ic_close_devs+0xc4/0x154 at addr ffff800367efa708
[    6.503013] Read of size 8 by task swapper/0/1
[    6.507452] CPU: 5 PID: 1 Comm: swapper/0 Not tainted 4.11.0-rc3-00002-gda42158 #8
[    6.514993] Hardware name: AppliedMicro Mustang/Mustang, BIOS 3.05.05-beta_rc Jan 27 2016
[    6.523138] Call trace:
[    6.525590] [<ffff200008094778>] dump_backtrace+0x0/0x570
[    6.530976] [<ffff200008094d08>] show_stack+0x20/0x30
[    6.536017] [<ffff200008bee928>] dump_stack+0x120/0x188
[    6.541231] [<ffff20000856d5e4>] kasan_object_err+0x24/0xa0
[    6.546790] [<ffff20000856d924>] kasan_report_error+0x244/0x738
[    6.552695] [<ffff20000856dfec>] __asan_report_load8_noabort+0x54/0x80
[    6.559204] [<ffff20000aae86ac>] ic_close_devs+0xc4/0x154
[    6.564590] [<ffff20000aaedbac>] ip_auto_config+0x2ed4/0x2f1c
[    6.570321] [<ffff200008084b04>] do_one_initcall+0xcc/0x370
[    6.575882] [<ffff20000aa31de8>] kernel_init_freeable+0x5f8/0x6c4
[    6.581959] [<ffff20000a16df00>] kernel_init+0x18/0x190
[    6.587171] [<ffff200008084710>] ret_from_fork+0x10/0x40
[    6.592468] Object at ffff800367efa700, in cache kmalloc-128 size: 128
[    6.598969] Allocated:
[    6.601324] PID = 1
[    6.603427]  save_stack_trace_tsk+0x0/0x418
[    6.607603]  save_stack_trace+0x20/0x30
[    6.611430]  kasan_kmalloc+0xd8/0x188
[    6.615087]  ip_auto_config+0x8c4/0x2f1c
[    6.619002]  do_one_initcall+0xcc/0x370
[    6.622832]  kernel_init_freeable+0x5f8/0x6c4
[    6.627178]  kernel_init+0x18/0x190
[    6.630660]  ret_from_fork+0x10/0x40
[    6.634223] Freed:
[    6.636233] PID = 1
[    6.638334]  save_stack_trace_tsk+0x0/0x418
[    6.642510]  save_stack_trace+0x20/0x30
[    6.646337]  kasan_slab_free+0x88/0x178
[    6.650167]  kfree+0xb8/0x478
[    6.653131]  ic_close_devs+0x130/0x154
[    6.656875]  ip_auto_config+0x2ed4/0x2f1c
[    6.660875]  do_one_initcall+0xcc/0x370
[    6.664705]  kernel_init_freeable+0x5f8/0x6c4
[    6.669051]  kernel_init+0x18/0x190
[    6.672534]  ret_from_fork+0x10/0x40
[    6.676098] Memory state around the buggy address:
[    6.680880]  ffff800367efa600: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[    6.688078]  ffff800367efa680: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[    6.695276] >ffff800367efa700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[    6.702469]                       ^
[    6.705952]  ffff800367efa780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[    6.713149]  ffff800367efa800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[    6.720343] ==================================================================
[    6.727536] Disabling lock debugging due to kernel taint

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
Cc: David S. Miller <davem@davemloft.net>
Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>
Cc: James Morris <jmorris@namei.org>
Cc: Patrick McHardy <kaber@trash.net>
Cc: netdev@vger.kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-27 21:06:53 -07:00
Gao Feng
75c689dca9 netfilter: nf_nat_snmp: Fix panic when snmp_trap_helper fails to register
In the commit 93557f53e1 ("netfilter: nf_conntrack: nf_conntrack snmp
helper"), the snmp_helper is replaced by nf_nat_snmp_hook. So the
snmp_helper is never registered. But it still tries to unregister the
snmp_helper, it could cause the panic.

Now remove the useless snmp_helper and the unregister call in the
error handler.

Fixes: 93557f53e1 ("netfilter: nf_conntrack: nf_conntrack snmp helper")
Signed-off-by: Gao Feng <fgao@ikuai8.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-03-27 13:49:13 +02:00
Liping Zhang
3b7dabf029 netfilter: invoke synchronize_rcu after set the _hook_ to NULL
Otherwise, another CPU may access the invalid pointer. For example:
    CPU0                CPU1
     -              rcu_read_lock();
     -              pfunc = _hook_;
  _hook_ = NULL;          -
  mod unload              -
     -                 pfunc(); // invalid, panic
     -             rcu_read_unlock();

So we must call synchronize_rcu() to wait the rcu reader to finish.

Also note, in nf_nat_snmp_basic_fini, synchronize_rcu() will be invoked
by later nf_conntrack_helper_unregister, but I'm inclined to add a
explicit synchronize_rcu after set the nf_nat_snmp_hook to NULL. Depend
on such obscure assumptions is not a good idea.

Last, in nfnetlink_cttimeout, we use kfree_rcu to free the time object,
so in cttimeout_exit, invoking rcu_barrier() is not necessary at all,
remove it too.

Signed-off-by: Liping Zhang <zlpnobody@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-03-27 13:47:28 +02:00
Eric Dumazet
43a6684519 ping: implement proper locking
We got a report of yet another bug in ping

http://www.openwall.com/lists/oss-security/2017/03/24/6

->disconnect() is not called with socket lock held.

Fix this by acquiring ping rwlock earlier.

Thanks to Daniel, Alexander and Andrey for letting us know this problem.

Fixes: c319b4d76b ("net: ipv4: add IPPROTO_ICMP socket kind")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Daniel Jiang <danieljiang0415@gmail.com>
Reported-by: Solar Designer <solar@openwall.com>
Reported-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-24 20:50:28 -07:00
Eric Dumazet
ec4fbd6475 inet: frag: release spinlock before calling icmp_send()
Dmitry reported a lockdep splat [1] (false positive) that we can fix
by releasing the spinlock before calling icmp_send() from ip_expire()

This is a false positive because sending an ICMP message can not
possibly re-enter the IP frag engine.

[1]
[ INFO: possible circular locking dependency detected ]
4.10.0+ #29 Not tainted
-------------------------------------------------------
modprobe/12392 is trying to acquire lock:
 (_xmit_ETHER#2){+.-...}, at: [<ffffffff837a8182>] spin_lock
include/linux/spinlock.h:299 [inline]
 (_xmit_ETHER#2){+.-...}, at: [<ffffffff837a8182>] __netif_tx_lock
include/linux/netdevice.h:3486 [inline]
 (_xmit_ETHER#2){+.-...}, at: [<ffffffff837a8182>]
sch_direct_xmit+0x282/0x6d0 net/sched/sch_generic.c:180

but task is already holding lock:
 (&(&q->lock)->rlock){+.-...}, at: [<ffffffff8389a4d1>] spin_lock
include/linux/spinlock.h:299 [inline]
 (&(&q->lock)->rlock){+.-...}, at: [<ffffffff8389a4d1>]
ip_expire+0x51/0x6c0 net/ipv4/ip_fragment.c:201

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #1 (&(&q->lock)->rlock){+.-...}:
       validate_chain kernel/locking/lockdep.c:2267 [inline]
       __lock_acquire+0x2149/0x3430 kernel/locking/lockdep.c:3340
       lock_acquire+0x2a1/0x630 kernel/locking/lockdep.c:3755
       __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline]
       _raw_spin_lock+0x33/0x50 kernel/locking/spinlock.c:151
       spin_lock include/linux/spinlock.h:299 [inline]
       ip_defrag+0x3a2/0x4130 net/ipv4/ip_fragment.c:669
       ip_check_defrag+0x4e3/0x8b0 net/ipv4/ip_fragment.c:713
       packet_rcv_fanout+0x282/0x800 net/packet/af_packet.c:1459
       deliver_skb net/core/dev.c:1834 [inline]
       dev_queue_xmit_nit+0x294/0xa90 net/core/dev.c:1890
       xmit_one net/core/dev.c:2903 [inline]
       dev_hard_start_xmit+0x16b/0xab0 net/core/dev.c:2923
       sch_direct_xmit+0x31f/0x6d0 net/sched/sch_generic.c:182
       __dev_xmit_skb net/core/dev.c:3092 [inline]
       __dev_queue_xmit+0x13e5/0x1e60 net/core/dev.c:3358
       dev_queue_xmit+0x17/0x20 net/core/dev.c:3423
       neigh_resolve_output+0x6b9/0xb10 net/core/neighbour.c:1308
       neigh_output include/net/neighbour.h:478 [inline]
       ip_finish_output2+0x8b8/0x15a0 net/ipv4/ip_output.c:228
       ip_do_fragment+0x1d93/0x2720 net/ipv4/ip_output.c:672
       ip_fragment.constprop.54+0x145/0x200 net/ipv4/ip_output.c:545
       ip_finish_output+0x82d/0xe10 net/ipv4/ip_output.c:314
       NF_HOOK_COND include/linux/netfilter.h:246 [inline]
       ip_output+0x1f0/0x7a0 net/ipv4/ip_output.c:404
       dst_output include/net/dst.h:486 [inline]
       ip_local_out+0x95/0x170 net/ipv4/ip_output.c:124
       ip_send_skb+0x3c/0xc0 net/ipv4/ip_output.c:1492
       ip_push_pending_frames+0x64/0x80 net/ipv4/ip_output.c:1512
       raw_sendmsg+0x26de/0x3a00 net/ipv4/raw.c:655
       inet_sendmsg+0x164/0x5b0 net/ipv4/af_inet.c:761
       sock_sendmsg_nosec net/socket.c:633 [inline]
       sock_sendmsg+0xca/0x110 net/socket.c:643
       ___sys_sendmsg+0x4a3/0x9f0 net/socket.c:1985
       __sys_sendmmsg+0x25c/0x750 net/socket.c:2075
       SYSC_sendmmsg net/socket.c:2106 [inline]
       SyS_sendmmsg+0x35/0x60 net/socket.c:2101
       do_syscall_64+0x2e8/0x930 arch/x86/entry/common.c:281
       return_from_SYSCALL_64+0x0/0x7a

-> #0 (_xmit_ETHER#2){+.-...}:
       check_prev_add kernel/locking/lockdep.c:1830 [inline]
       check_prevs_add+0xa8f/0x19f0 kernel/locking/lockdep.c:1940
       validate_chain kernel/locking/lockdep.c:2267 [inline]
       __lock_acquire+0x2149/0x3430 kernel/locking/lockdep.c:3340
       lock_acquire+0x2a1/0x630 kernel/locking/lockdep.c:3755
       __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline]
       _raw_spin_lock+0x33/0x50 kernel/locking/spinlock.c:151
       spin_lock include/linux/spinlock.h:299 [inline]
       __netif_tx_lock include/linux/netdevice.h:3486 [inline]
       sch_direct_xmit+0x282/0x6d0 net/sched/sch_generic.c:180
       __dev_xmit_skb net/core/dev.c:3092 [inline]
       __dev_queue_xmit+0x13e5/0x1e60 net/core/dev.c:3358
       dev_queue_xmit+0x17/0x20 net/core/dev.c:3423
       neigh_hh_output include/net/neighbour.h:468 [inline]
       neigh_output include/net/neighbour.h:476 [inline]
       ip_finish_output2+0xf6c/0x15a0 net/ipv4/ip_output.c:228
       ip_finish_output+0xa29/0xe10 net/ipv4/ip_output.c:316
       NF_HOOK_COND include/linux/netfilter.h:246 [inline]
       ip_output+0x1f0/0x7a0 net/ipv4/ip_output.c:404
       dst_output include/net/dst.h:486 [inline]
       ip_local_out+0x95/0x170 net/ipv4/ip_output.c:124
       ip_send_skb+0x3c/0xc0 net/ipv4/ip_output.c:1492
       ip_push_pending_frames+0x64/0x80 net/ipv4/ip_output.c:1512
       icmp_push_reply+0x372/0x4d0 net/ipv4/icmp.c:394
       icmp_send+0x156c/0x1c80 net/ipv4/icmp.c:754
       ip_expire+0x40e/0x6c0 net/ipv4/ip_fragment.c:239
       call_timer_fn+0x241/0x820 kernel/time/timer.c:1268
       expire_timers kernel/time/timer.c:1307 [inline]
       __run_timers+0x960/0xcf0 kernel/time/timer.c:1601
       run_timer_softirq+0x21/0x80 kernel/time/timer.c:1614
       __do_softirq+0x31f/0xbe7 kernel/softirq.c:284
       invoke_softirq kernel/softirq.c:364 [inline]
       irq_exit+0x1cc/0x200 kernel/softirq.c:405
       exiting_irq arch/x86/include/asm/apic.h:657 [inline]
       smp_apic_timer_interrupt+0x76/0xa0 arch/x86/kernel/apic/apic.c:962
       apic_timer_interrupt+0x93/0xa0 arch/x86/entry/entry_64.S:707
       __read_once_size include/linux/compiler.h:254 [inline]
       atomic_read arch/x86/include/asm/atomic.h:26 [inline]
       rcu_dynticks_curr_cpu_in_eqs kernel/rcu/tree.c:350 [inline]
       __rcu_is_watching kernel/rcu/tree.c:1133 [inline]
       rcu_is_watching+0x83/0x110 kernel/rcu/tree.c:1147
       rcu_read_lock_held+0x87/0xc0 kernel/rcu/update.c:293
       radix_tree_deref_slot include/linux/radix-tree.h:238 [inline]
       filemap_map_pages+0x6d4/0x1570 mm/filemap.c:2335
       do_fault_around mm/memory.c:3231 [inline]
       do_read_fault mm/memory.c:3265 [inline]
       do_fault+0xbd5/0x2080 mm/memory.c:3370
       handle_pte_fault mm/memory.c:3600 [inline]
       __handle_mm_fault+0x1062/0x2cb0 mm/memory.c:3714
       handle_mm_fault+0x1e2/0x480 mm/memory.c:3751
       __do_page_fault+0x4f6/0xb60 arch/x86/mm/fault.c:1397
       do_page_fault+0x54/0x70 arch/x86/mm/fault.c:1460
       page_fault+0x28/0x30 arch/x86/entry/entry_64.S:1011

other info that might help us debug this:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&(&q->lock)->rlock);
                               lock(_xmit_ETHER#2);
                               lock(&(&q->lock)->rlock);
  lock(_xmit_ETHER#2);

 *** DEADLOCK ***

10 locks held by modprobe/12392:
 #0:  (&mm->mmap_sem){++++++}, at: [<ffffffff81329758>]
__do_page_fault+0x2b8/0xb60 arch/x86/mm/fault.c:1336
 #1:  (rcu_read_lock){......}, at: [<ffffffff8188cab6>]
filemap_map_pages+0x1e6/0x1570 mm/filemap.c:2324
 #2:  (&(ptlock_ptr(page))->rlock#2){+.+...}, at: [<ffffffff81984a78>]
spin_lock include/linux/spinlock.h:299 [inline]
 #2:  (&(ptlock_ptr(page))->rlock#2){+.+...}, at: [<ffffffff81984a78>]
pte_alloc_one_map mm/memory.c:2944 [inline]
 #2:  (&(ptlock_ptr(page))->rlock#2){+.+...}, at: [<ffffffff81984a78>]
alloc_set_pte+0x13b8/0x1b90 mm/memory.c:3072
 #3:  (((&q->timer))){+.-...}, at: [<ffffffff81627e72>]
lockdep_copy_map include/linux/lockdep.h:175 [inline]
 #3:  (((&q->timer))){+.-...}, at: [<ffffffff81627e72>]
call_timer_fn+0x1c2/0x820 kernel/time/timer.c:1258
 #4:  (&(&q->lock)->rlock){+.-...}, at: [<ffffffff8389a4d1>] spin_lock
include/linux/spinlock.h:299 [inline]
 #4:  (&(&q->lock)->rlock){+.-...}, at: [<ffffffff8389a4d1>]
ip_expire+0x51/0x6c0 net/ipv4/ip_fragment.c:201
 #5:  (rcu_read_lock){......}, at: [<ffffffff8389a633>]
ip_expire+0x1b3/0x6c0 net/ipv4/ip_fragment.c:216
 #6:  (slock-AF_INET){+.-...}, at: [<ffffffff839b3313>] spin_trylock
include/linux/spinlock.h:309 [inline]
 #6:  (slock-AF_INET){+.-...}, at: [<ffffffff839b3313>] icmp_xmit_lock
net/ipv4/icmp.c:219 [inline]
 #6:  (slock-AF_INET){+.-...}, at: [<ffffffff839b3313>]
icmp_send+0x803/0x1c80 net/ipv4/icmp.c:681
 #7:  (rcu_read_lock_bh){......}, at: [<ffffffff838ab9a1>]
ip_finish_output2+0x2c1/0x15a0 net/ipv4/ip_output.c:198
 #8:  (rcu_read_lock_bh){......}, at: [<ffffffff836d1dee>]
__dev_queue_xmit+0x23e/0x1e60 net/core/dev.c:3324
 #9:  (dev->qdisc_running_key ?: &qdisc_running_key){+.....}, at:
[<ffffffff836d3a27>] dev_queue_xmit+0x17/0x20 net/core/dev.c:3423

stack backtrace:
CPU: 0 PID: 12392 Comm: modprobe Not tainted 4.10.0+ #29
Hardware name: Google Google Compute Engine/Google Compute Engine,
BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:16 [inline]
 dump_stack+0x2ee/0x3ef lib/dump_stack.c:52
 print_circular_bug+0x307/0x3b0 kernel/locking/lockdep.c:1204
 check_prev_add kernel/locking/lockdep.c:1830 [inline]
 check_prevs_add+0xa8f/0x19f0 kernel/locking/lockdep.c:1940
 validate_chain kernel/locking/lockdep.c:2267 [inline]
 __lock_acquire+0x2149/0x3430 kernel/locking/lockdep.c:3340
 lock_acquire+0x2a1/0x630 kernel/locking/lockdep.c:3755
 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline]
 _raw_spin_lock+0x33/0x50 kernel/locking/spinlock.c:151
 spin_lock include/linux/spinlock.h:299 [inline]
 __netif_tx_lock include/linux/netdevice.h:3486 [inline]
 sch_direct_xmit+0x282/0x6d0 net/sched/sch_generic.c:180
 __dev_xmit_skb net/core/dev.c:3092 [inline]
 __dev_queue_xmit+0x13e5/0x1e60 net/core/dev.c:3358
 dev_queue_xmit+0x17/0x20 net/core/dev.c:3423
 neigh_hh_output include/net/neighbour.h:468 [inline]
 neigh_output include/net/neighbour.h:476 [inline]
 ip_finish_output2+0xf6c/0x15a0 net/ipv4/ip_output.c:228
 ip_finish_output+0xa29/0xe10 net/ipv4/ip_output.c:316
 NF_HOOK_COND include/linux/netfilter.h:246 [inline]
 ip_output+0x1f0/0x7a0 net/ipv4/ip_output.c:404
 dst_output include/net/dst.h:486 [inline]
 ip_local_out+0x95/0x170 net/ipv4/ip_output.c:124
 ip_send_skb+0x3c/0xc0 net/ipv4/ip_output.c:1492
 ip_push_pending_frames+0x64/0x80 net/ipv4/ip_output.c:1512
 icmp_push_reply+0x372/0x4d0 net/ipv4/icmp.c:394
 icmp_send+0x156c/0x1c80 net/ipv4/icmp.c:754
 ip_expire+0x40e/0x6c0 net/ipv4/ip_fragment.c:239
 call_timer_fn+0x241/0x820 kernel/time/timer.c:1268
 expire_timers kernel/time/timer.c:1307 [inline]
 __run_timers+0x960/0xcf0 kernel/time/timer.c:1601
 run_timer_softirq+0x21/0x80 kernel/time/timer.c:1614
 __do_softirq+0x31f/0xbe7 kernel/softirq.c:284
 invoke_softirq kernel/softirq.c:364 [inline]
 irq_exit+0x1cc/0x200 kernel/softirq.c:405
 exiting_irq arch/x86/include/asm/apic.h:657 [inline]
 smp_apic_timer_interrupt+0x76/0xa0 arch/x86/kernel/apic/apic.c:962
 apic_timer_interrupt+0x93/0xa0 arch/x86/entry/entry_64.S:707
RIP: 0010:__read_once_size include/linux/compiler.h:254 [inline]
RIP: 0010:atomic_read arch/x86/include/asm/atomic.h:26 [inline]
RIP: 0010:rcu_dynticks_curr_cpu_in_eqs kernel/rcu/tree.c:350 [inline]
RIP: 0010:__rcu_is_watching kernel/rcu/tree.c:1133 [inline]
RIP: 0010:rcu_is_watching+0x83/0x110 kernel/rcu/tree.c:1147
RSP: 0000:ffff8801c391f120 EFLAGS: 00000a03 ORIG_RAX: ffffffffffffff10
RAX: dffffc0000000000 RBX: ffff8801c391f148 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 000055edd4374000 RDI: ffff8801dbe1ae0c
RBP: ffff8801c391f1a0 R08: 0000000000000002 R09: 0000000000000000
R10: dffffc0000000000 R11: 0000000000000002 R12: 1ffff10038723e25
R13: ffff8801dbe1ae00 R14: ffff8801c391f680 R15: dffffc0000000000
 </IRQ>
 rcu_read_lock_held+0x87/0xc0 kernel/rcu/update.c:293
 radix_tree_deref_slot include/linux/radix-tree.h:238 [inline]
 filemap_map_pages+0x6d4/0x1570 mm/filemap.c:2335
 do_fault_around mm/memory.c:3231 [inline]
 do_read_fault mm/memory.c:3265 [inline]
 do_fault+0xbd5/0x2080 mm/memory.c:3370
 handle_pte_fault mm/memory.c:3600 [inline]
 __handle_mm_fault+0x1062/0x2cb0 mm/memory.c:3714
 handle_mm_fault+0x1e2/0x480 mm/memory.c:3751
 __do_page_fault+0x4f6/0xb60 arch/x86/mm/fault.c:1397
 do_page_fault+0x54/0x70 arch/x86/mm/fault.c:1460
 page_fault+0x28/0x30 arch/x86/entry/entry_64.S:1011
RIP: 0033:0x7f83172f2786
RSP: 002b:00007fffe859ae80 EFLAGS: 00010293
RAX: 000055edd4373040 RBX: 00007f83175111c8 RCX: 000055edd4373238
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00007f8317510970
RBP: 00007fffe859afd0 R08: 0000000000000009 R09: 0000000000000000
R10: 0000000000000064 R11: 0000000000000000 R12: 000055edd4373040
R13: 0000000000000000 R14: 00007fffe859afe8 R15: 0000000000000000

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-22 15:40:45 -07:00
Eric Dumazet
15bb7745e9 tcp: initialize icsk_ack.lrcvtime at session start time
icsk_ack.lrcvtime has a 0 value at socket creation time.

tcpi_last_data_recv can have bogus value if no payload is ever received.

This patch initializes icsk_ack.lrcvtime for active sessions
in tcp_finish_connect(), and for passive sessions in
tcp_create_openreq_child()

Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-22 15:39:42 -07:00
Eric Dumazet
c64c0b3cac ipv4: provide stronger user input validation in nl_fib_input()
Alexander reported a KMSAN splat caused by reads of uninitialized
field (tb_id_in) from user provided struct fib_result_nl

It turns out nl_fib_input() sanity tests on user input is a bit
wrong :

User can pretend nlh->nlmsg_len is big enough, but provide
at sendmsg() time a too small buffer.

Reported-by: Alexander Potapenko <glider@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-22 14:15:49 -07:00
Eric Dumazet
db7f00b8db tcp: tcp_get_info() should read tcp_time_stamp later
Commit b369e7fd41 ("tcp: make TCP_INFO more consistent") moved
lock_sock_fast() earlier in tcp_get_info()

This has the minor effect that jiffies value being sampled at the
beginning of tcp_get_info() is more likely to be off by one, and we
report big tcpi_last_data_sent values (like 0xFFFFFFFF).

Since we lock the socket, fetching tcp_time_stamp right before
doing the jiffies_to_msecs() calls is enough to remove these
wrong values.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-16 21:37:13 -07:00
David S. Miller
e11607aad5 Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf
Pablo Neira Ayuso says:

====================
Netfilter fixes for net

The following patchset contains Netfilter fixes for your net tree, a
rather large batch of fixes targeted to nf_tables, conntrack and bridge
netfilter. More specifically, they are:

1) Don't track fragmented packets if the socket option IP_NODEFRAG is set.
   From Florian Westphal.

2) SCTP protocol tracker assumes that ICMP error messages contain the
   checksum field, what results in packet drops. From Ying Xue.

3) Fix inconsistent handling of AH traffic from nf_tables.

4) Fix new bitmap set representation with big endian. Fix mismatches in
   nf_tables due to incorrect big endian handling too. Both patches
   from Liping Zhang.

5) Bridge netfilter doesn't honor maximum fragment size field, cap to
   largest fragment seen. From Florian Westphal.

6) Fake conntrack entry needs to be aligned to 8 bytes since the 3 LSB
   bits are now used to store the ctinfo. From Steven Rostedt.

7) Fix element comments with the bitmap set type. Revert the flush
   field in the nft_set_iter structure, not required anymore after
   fixing up element comments.

8) Missing error on invalid conntrack direction from nft_ct, also from
   Liping Zhang.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-15 15:13:13 -07:00
Jon Maxwell
45caeaa5ac dccp/tcp: fix routing redirect race
As Eric Dumazet pointed out this also needs to be fixed in IPv6.
v2: Contains the IPv6 tcp/Ipv6 dccp patches as well.

We have seen a few incidents lately where a dst_enty has been freed
with a dangling TCP socket reference (sk->sk_dst_cache) pointing to that
dst_entry. If the conditions/timings are right a crash then ensues when the
freed dst_entry is referenced later on. A Common crashing back trace is:

 #8 [] page_fault at ffffffff8163e648
    [exception RIP: __tcp_ack_snd_check+74]
.
.
 #9 [] tcp_rcv_established at ffffffff81580b64
#10 [] tcp_v4_do_rcv at ffffffff8158b54a
#11 [] tcp_v4_rcv at ffffffff8158cd02
#12 [] ip_local_deliver_finish at ffffffff815668f4
#13 [] ip_local_deliver at ffffffff81566bd9
#14 [] ip_rcv_finish at ffffffff8156656d
#15 [] ip_rcv at ffffffff81566f06
#16 [] __netif_receive_skb_core at ffffffff8152b3a2
#17 [] __netif_receive_skb at ffffffff8152b608
#18 [] netif_receive_skb at ffffffff8152b690
#19 [] vmxnet3_rq_rx_complete at ffffffffa015eeaf [vmxnet3]
#20 [] vmxnet3_poll_rx_only at ffffffffa015f32a [vmxnet3]
#21 [] net_rx_action at ffffffff8152bac2
#22 [] __do_softirq at ffffffff81084b4f
#23 [] call_softirq at ffffffff8164845c
#24 [] do_softirq at ffffffff81016fc5
#25 [] irq_exit at ffffffff81084ee5
#26 [] do_IRQ at ffffffff81648ff8

Of course it may happen with other NIC drivers as well.

It's found the freed dst_entry here:

 224 static bool tcp_in_quickack_mode(struct sock *sk)↩
 225 {↩
 226 ▹       const struct inet_connection_sock *icsk = inet_csk(sk);↩
 227 ▹       const struct dst_entry *dst = __sk_dst_get(sk);↩
 228 ↩
 229 ▹       return (dst && dst_metric(dst, RTAX_QUICKACK)) ||↩
 230 ▹       ▹       (icsk->icsk_ack.quick && !icsk->icsk_ack.pingpong);↩
 231 }↩

But there are other backtraces attributed to the same freed dst_entry in
netfilter code as well.

All the vmcores showed 2 significant clues:

- Remote hosts behind the default gateway had always been redirected to a
different gateway. A rtable/dst_entry will be added for that host. Making
more dst_entrys with lower reference counts. Making this more probable.

- All vmcores showed a postitive LockDroppedIcmps value, e.g:

LockDroppedIcmps                  267

A closer look at the tcp_v4_err() handler revealed that do_redirect() will run
regardless of whether user space has the socket locked. This can result in a
race condition where the same dst_entry cached in sk->sk_dst_entry can be
decremented twice for the same socket via:

do_redirect()->__sk_dst_check()-> dst_release().

Which leads to the dst_entry being prematurely freed with another socket
pointing to it via sk->sk_dst_cache and a subsequent crash.

To fix this skip do_redirect() if usespace has the socket locked. Instead let
the redirect take place later when user space does not have the socket
locked.

The dccp/IPv6 code is very similar in this respect, so fixing it there too.

As Eric Garver pointed out the following commit now invalidates routes. Which
can set the dst->obsolete flag so that ipv4_dst_check() returns null and
triggers the dst_release().

Fixes: ceb3320610 ("ipv4: Kill routes during PMTU/redirect updates.")
Cc: Eric Garver <egarver@redhat.com>
Cc: Hannes Sowa <hsowa@redhat.com>
Signed-off-by: Jon Maxwell <jmaxwell37@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-13 21:55:47 -07:00
Liping Zhang
10596608c4 netfilter: nf_tables: fix mismatch in big-endian system
Currently, there are two different methods to store an u16 integer to
the u32 data register. For example:
  u32 *dest = &regs->data[priv->dreg];
  1. *dest = 0; *(u16 *) dest = val_u16;
  2. *dest = val_u16;

For method 1, the u16 value will be stored like this, either in
big-endian or little-endian system:
  0          15           31
  +-+-+-+-+-+-+-+-+-+-+-+-+
  |   Value   |     0     |
  +-+-+-+-+-+-+-+-+-+-+-+-+

For method 2, in little-endian system, the u16 value will be the same
as listed above. But in big-endian system, the u16 value will be stored
like this:
  0          15           31
  +-+-+-+-+-+-+-+-+-+-+-+-+
  |     0     |   Value   |
  +-+-+-+-+-+-+-+-+-+-+-+-+

So later we use "memcmp(&regs->data[priv->sreg], data, 2);" to do
compare in nft_cmp, nft_lookup expr ..., method 2 will get the wrong
result in big-endian system, as 0~15 bits will always be zero.

For the similar reason, when loading an u16 value from the u32 data
register, we should use "*(u16 *) sreg;" instead of "(u16)*sreg;",
the 2nd method will get the wrong value in the big-endian system.

So introduce some wrapper functions to store/load an u8 or u16
integer to/from the u32 data register, and use them in the right
place.

Signed-off-by: Liping Zhang <zlpnobody@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-03-13 13:30:28 +01:00
Alexey Kodanev
4b3b45edba udp: avoid ufo handling on IP payload compression packets
commit c146066ab8 ("ipv4: Don't use ufo handling on later transformed
packets") and commit f89c56ce71 ("ipv6: Don't use ufo handling on
later transformed packets") added a check that 'rt->dst.header_len' isn't
zero in order to skip UFO, but it doesn't include IPcomp in transport mode
where it equals zero.

Packets, after payload compression, may not require further fragmentation,
and if original length exceeds MTU, later compressed packets will be
transmitted incorrectly. This can be reproduced with LTP udp_ipsec.sh test
on veth device with enabled UFO, MTU is 1500 and UDP payload is 2000:

* IPv4 case, offset is wrong + unnecessary fragmentation
    udp_ipsec.sh -p comp -m transport -s 2000 &
    tcpdump -ni ltp_ns_veth2
    ...
    IP (tos 0x0, ttl 64, id 45203, offset 0, flags [+],
      proto Compressed IP (108), length 49)
      10.0.0.2 > 10.0.0.1: IPComp(cpi=0x1000)
    IP (tos 0x0, ttl 64, id 45203, offset 1480, flags [none],
      proto UDP (17), length 21) 10.0.0.2 > 10.0.0.1: ip-proto-17

* IPv6 case, sending small fragments
    udp_ipsec.sh -6 -p comp -m transport -s 2000 &
    tcpdump -ni ltp_ns_veth2
    ...
    IP6 (flowlabel 0x6b9ba, hlim 64, next-header Compressed IP (108)
      payload length: 37) fd00::2 > fd00::1: IPComp(cpi=0x1000)
    IP6 (flowlabel 0x6b9ba, hlim 64, next-header Compressed IP (108)
      payload length: 21) fd00::2 > fd00::1: IPComp(cpi=0x1000)

Fix it by checking 'rt->dst.xfrm' pointer to 'xfrm_state' struct, skip UFO
if xfrm is set. So the new check will include both cases: IPcomp and IPsec.

Fixes: c146066ab8 ("ipv4: Don't use ufo handling on later transformed packets")
Fixes: f89c56ce71 ("ipv6: Don't use ufo handling on later transformed packets")
Signed-off-by: Alexey Kodanev <alexey.kodanev@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-09 18:28:42 -08:00
David Howells
cdfbabfb2f net: Work around lockdep limitation in sockets that use sockets
Lockdep issues a circular dependency warning when AFS issues an operation
through AF_RXRPC from a context in which the VFS/VM holds the mmap_sem.

The theory lockdep comes up with is as follows:

 (1) If the pagefault handler decides it needs to read pages from AFS, it
     calls AFS with mmap_sem held and AFS begins an AF_RXRPC call, but
     creating a call requires the socket lock:

	mmap_sem must be taken before sk_lock-AF_RXRPC

 (2) afs_open_socket() opens an AF_RXRPC socket and binds it.  rxrpc_bind()
     binds the underlying UDP socket whilst holding its socket lock.
     inet_bind() takes its own socket lock:

	sk_lock-AF_RXRPC must be taken before sk_lock-AF_INET

 (3) Reading from a TCP socket into a userspace buffer might cause a fault
     and thus cause the kernel to take the mmap_sem, but the TCP socket is
     locked whilst doing this:

	sk_lock-AF_INET must be taken before mmap_sem

However, lockdep's theory is wrong in this instance because it deals only
with lock classes and not individual locks.  The AF_INET lock in (2) isn't
really equivalent to the AF_INET lock in (3) as the former deals with a
socket entirely internal to the kernel that never sees userspace.  This is
a limitation in the design of lockdep.

Fix the general case by:

 (1) Double up all the locking keys used in sockets so that one set are
     used if the socket is created by userspace and the other set is used
     if the socket is created by the kernel.

 (2) Store the kern parameter passed to sk_alloc() in a variable in the
     sock struct (sk_kern_sock).  This informs sock_lock_init(),
     sock_init_data() and sk_clone_lock() as to the lock keys to be used.

     Note that the child created by sk_clone_lock() inherits the parent's
     kern setting.

 (3) Add a 'kern' parameter to ->accept() that is analogous to the one
     passed in to ->create() that distinguishes whether kernel_accept() or
     sys_accept4() was the caller and can be passed to sk_alloc().

     Note that a lot of accept functions merely dequeue an already
     allocated socket.  I haven't touched these as the new socket already
     exists before we get the parameter.

     Note also that there are a couple of places where I've made the accepted
     socket unconditionally kernel-based:

	irda_accept()
	rds_rcp_accept_one()
	tcp_accept_from_sock()

     because they follow a sock_create_kern() and accept off of that.

Whilst creating this, I noticed that lustre and ocfs don't create sockets
through sock_create_kern() and thus they aren't marked as for-kernel,
though they appear to be internal.  I wonder if these should do that so
that they use the new set of lock keys.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-09 18:23:27 -08:00
Paolo Abeni
294acf1c01 net/tunnel: set inner protocol in network gro hooks
The gso code of several tunnels type (gre and udp tunnels)
takes for granted that the skb->inner_protocol is properly
initialized and drops the packet elsewhere.

On the forwarding path no one is initializing such field,
so gro encapsulated packets are dropped on forward.

Since commit 3872035241 ("gre: Use inner_proto to obtain
inner header protocol"), this can be reproduced when the
encapsulated packets use gre as the tunneling protocol.

The issue happens also with vxlan and geneve tunnels since
commit 8bce6d7d0d ("udp: Generalize skb_udp_segment"), if the
forwarding host's ingress nic has h/w offload for such tunnel
and a vxlan/geneve device is configured on top of it, regardless
of the configured peer address and vni.

To address the issue, this change initialize the inner_protocol
field for encapsulated packets in both ipv4 and ipv6 gro complete
callbacks.

Fixes: 3872035241 ("gre: Use inner_proto to obtain inner header protocol")
Fixes: 8bce6d7d0d ("udp: Generalize skb_udp_segment")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Acked-by: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-09 13:19:52 -08:00
Florian Westphal
7b4fdf77a4 netfilter: don't track fragmented packets
Andrey reports syzkaller splat caused by

NF_CT_ASSERT(!ip_is_fragment(ip_hdr(skb)));

in ipv4 nat.  But this assertion (and the comment) are wrong, this function
does see fragments when IP_NODEFRAG setsockopt is used.

As conntrack doesn't track packets without complete l4 header, only the
first fragment is tracked.

Because applying nat to first packet but not the rest makes no sense this
also turns off tracking of all fragments.

Reported-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-03-08 18:02:12 +01:00
Eric Dumazet
02b2faaf0a tcp: fix various issues for sockets morphing to listen state
Dmitry Vyukov reported a divide by 0 triggered by syzkaller, exploiting
tcp_disconnect() path that was never really considered and/or used
before syzkaller ;)

I was not able to reproduce the bug, but it seems issues here are the
three possible actions that assumed they would never trigger on a
listener.

1) tcp_write_timer_handler
2) tcp_delack_timer_handler
3) MTU reduction

Only IPv6 MTU reduction was properly testing TCP_CLOSE and TCP_LISTEN
 states from tcp_v6_mtu_reduced()

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-07 13:58:33 -08:00
Linus Torvalds
8d70eeb84a Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:

 1) Fix double-free in batman-adv, from Sven Eckelmann.

 2) Fix packet stats for fast-RX path, from Joannes Berg.

 3) Netfilter's ip_route_me_harder() doesn't handle request sockets
    properly, fix from Florian Westphal.

 4) Fix sendmsg deadlock in rxrpc, from David Howells.

 5) Add missing RCU locking to transport hashtable scan, from Xin Long.

 6) Fix potential packet loss in mlxsw driver, from Ido Schimmel.

 7) Fix race in NAPI handling between poll handlers and busy polling,
    from Eric Dumazet.

 8) TX path in vxlan and geneve need proper RCU locking, from Jakub
    Kicinski.

 9) SYN processing in DCCP and TCP need to disable BH, from Eric
    Dumazet.

10) Properly handle net_enable_timestamp() being invoked from IRQ
    context, also from Eric Dumazet.

11) Fix crash on device-tree systems in xgene driver, from Alban Bedel.

12) Do not call sk_free() on a locked socket, from Arnaldo Carvalho de
    Melo.

13) Fix use-after-free in netvsc driver, from Dexuan Cui.

14) Fix max MTU setting in bonding driver, from WANG Cong.

15) xen-netback hash table can be allocated from softirq context, so use
    GFP_ATOMIC. From Anoob Soman.

16) Fix MAC address change bug in bgmac driver, from Hari Vyas.

17) strparser needs to destroy strp_wq on module exit, from WANG Cong.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (69 commits)
  strparser: destroy workqueue on module exit
  sfc: fix IPID endianness in TSOv2
  sfc: avoid max() in array size
  rds: remove unnecessary returned value check
  rxrpc: Fix potential NULL-pointer exception
  nfp: correct DMA direction in XDP DMA sync
  nfp: don't tell FW about the reserved buffer space
  net: ethernet: bgmac: mac address change bug
  net: ethernet: bgmac: init sequence bug
  xen-netback: don't vfree() queues under spinlock
  xen-netback: keep a local pointer for vif in backend_disconnect()
  netfilter: nf_tables: don't call nfnetlink_set_err() if nfnetlink_send() fails
  netfilter: nft_set_rbtree: incorrect assumption on lower interval lookups
  netfilter: nf_conntrack_sip: fix wrong memory initialisation
  can: flexcan: fix typo in comment
  can: usb_8dev: Fix memory leak of priv->cmd_msg_buffer
  can: gs_usb: fix coding style
  can: gs_usb: Don't use stack memory for USB transfers
  ixgbe: Limit use of 2K buffers on architectures with 256B or larger cache lines
  ixgbe: update the rss key on h/w, when ethtool ask for it
  ...
2017-03-04 17:31:39 -08:00
David S. Miller
20b83643ab Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf
Pablo Neira Ayuso says:

====================
Netfilter fixes for net

The following patchset contains Netfilter fixes for your net tree,
they are:

1) Missing check for full sock in ip_route_me_harder(), from
   Florian Westphal.

2) Incorrect sip helper structure initilization that breaks it when
   several ports are used, from Christophe Leroy.

3) Fix incorrect assumption when looking up for matching with adjacent
   intervals in the nft_set_rbtree.

4) Fix broken netlink event error reporting in nf_tables that results
   in misleading ESRCH errors propagated to userspace listeners.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-03 20:40:06 -08:00
Wei Wang
7db92362d2 tcp: fix potential double free issue for fastopen_req
tp->fastopen_req could potentially be double freed if a malicious
user does the following:
1. Enable TCP_FASTOPEN_CONNECT sockopt and do a connect() on the socket.
2. Call connect() with AF_UNSPEC to disconnect the socket.
3. Make this socket a listening socket by calling listen().
4. Accept incoming connections and generate child sockets. All child
   sockets will get a copy of the pointer of fastopen_req.
5. Call close() on all sockets. fastopen_req will get freed multiple
   times.

Fixes: 19f6d3f3c8 ("net/tcp-fastopen: Add new API support")
Reported-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Wei Wang <weiwan@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-02 14:05:41 -08:00
Ingo Molnar
174cd4b1e5 sched/headers: Prepare to move signal wakeup & sigpending methods from <linux/sched.h> into <linux/sched/signal.h>
Fix up affected files that include this signal functionality via sched.h.

Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-02 08:42:32 +01:00
Ingo Molnar
e601757102 sched/headers: Prepare for new header dependencies before moving code to <linux/sched/clock.h>
We are going to split <linux/sched/clock.h> out of <linux/sched.h>, which
will have to be picked up from other headers and .c files.

Create a trivial placeholder <linux/sched/clock.h> file that just
maps to <linux/sched.h> to make this patch obviously correct and
bisectable.

Include the new header in the files that are going to need it.

Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-02 08:42:27 +01:00
Eric Dumazet
449809a66c tcp/dccp: block BH for SYN processing
SYN processing really was meant to be handled from BH.

When I got rid of BH blocking while processing socket backlog
in commit 5413d1babe ("net: do not block BH while processing socket
backlog"), I forgot that a malicious user could transition to TCP_LISTEN
from a state that allowed (SYN) packets to be parked in the socket
backlog while socket is owned by the thread doing the listen() call.

Sure enough syzkaller found this and reported the bug ;)

=================================
[ INFO: inconsistent lock state ]
4.10.0+ #60 Not tainted
---------------------------------
inconsistent {IN-SOFTIRQ-W} -> {SOFTIRQ-ON-W} usage.
syz-executor0/5090 [HC0[0]:SC0[0]:HE1:SE1] takes:
 (&(&hashinfo->ehash_locks[i])->rlock){+.?...}, at:
[<ffffffff83a6a370>] spin_lock include/linux/spinlock.h:299 [inline]
 (&(&hashinfo->ehash_locks[i])->rlock){+.?...}, at:
[<ffffffff83a6a370>] inet_ehash_insert+0x240/0xad0
net/ipv4/inet_hashtables.c:407
{IN-SOFTIRQ-W} state was registered at:
  mark_irqflags kernel/locking/lockdep.c:2923 [inline]
  __lock_acquire+0xbcf/0x3270 kernel/locking/lockdep.c:3295
  lock_acquire+0x241/0x580 kernel/locking/lockdep.c:3753
  __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline]
  _raw_spin_lock+0x33/0x50 kernel/locking/spinlock.c:151
  spin_lock include/linux/spinlock.h:299 [inline]
  inet_ehash_insert+0x240/0xad0 net/ipv4/inet_hashtables.c:407
  reqsk_queue_hash_req net/ipv4/inet_connection_sock.c:753 [inline]
  inet_csk_reqsk_queue_hash_add+0x1b7/0x2a0 net/ipv4/inet_connection_sock.c:764
  tcp_conn_request+0x25cc/0x3310 net/ipv4/tcp_input.c:6399
  tcp_v4_conn_request+0x157/0x220 net/ipv4/tcp_ipv4.c:1262
  tcp_rcv_state_process+0x802/0x4130 net/ipv4/tcp_input.c:5889
  tcp_v4_do_rcv+0x56b/0x940 net/ipv4/tcp_ipv4.c:1433
  tcp_v4_rcv+0x2e12/0x3210 net/ipv4/tcp_ipv4.c:1711
  ip_local_deliver_finish+0x4ce/0xc40 net/ipv4/ip_input.c:216
  NF_HOOK include/linux/netfilter.h:257 [inline]
  ip_local_deliver+0x1ce/0x710 net/ipv4/ip_input.c:257
  dst_input include/net/dst.h:492 [inline]
  ip_rcv_finish+0xb1d/0x2110 net/ipv4/ip_input.c:396
  NF_HOOK include/linux/netfilter.h:257 [inline]
  ip_rcv+0xd90/0x19c0 net/ipv4/ip_input.c:487
  __netif_receive_skb_core+0x1ad1/0x3400 net/core/dev.c:4179
  __netif_receive_skb+0x2a/0x170 net/core/dev.c:4217
  netif_receive_skb_internal+0x1d6/0x430 net/core/dev.c:4245
  napi_skb_finish net/core/dev.c:4602 [inline]
  napi_gro_receive+0x4e6/0x680 net/core/dev.c:4636
  e1000_receive_skb drivers/net/ethernet/intel/e1000/e1000_main.c:4033 [inline]
  e1000_clean_rx_irq+0x5e0/0x1490
drivers/net/ethernet/intel/e1000/e1000_main.c:4489
  e1000_clean+0xb9a/0x2910 drivers/net/ethernet/intel/e1000/e1000_main.c:3834
  napi_poll net/core/dev.c:5171 [inline]
  net_rx_action+0xe70/0x1900 net/core/dev.c:5236
  __do_softirq+0x2fb/0xb7d kernel/softirq.c:284
  invoke_softirq kernel/softirq.c:364 [inline]
  irq_exit+0x19e/0x1d0 kernel/softirq.c:405
  exiting_irq arch/x86/include/asm/apic.h:658 [inline]
  do_IRQ+0x81/0x1a0 arch/x86/kernel/irq.c:250
  ret_from_intr+0x0/0x20
  native_safe_halt+0x6/0x10 arch/x86/include/asm/irqflags.h:53
  arch_safe_halt arch/x86/include/asm/paravirt.h:98 [inline]
  default_idle+0x8f/0x410 arch/x86/kernel/process.c:271
  arch_cpu_idle+0xa/0x10 arch/x86/kernel/process.c:262
  default_idle_call+0x36/0x60 kernel/sched/idle.c:96
  cpuidle_idle_call kernel/sched/idle.c:154 [inline]
  do_idle+0x348/0x440 kernel/sched/idle.c:243
  cpu_startup_entry+0x18/0x20 kernel/sched/idle.c:345
  start_secondary+0x344/0x440 arch/x86/kernel/smpboot.c:272
  verify_cpu+0x0/0xfc
irq event stamp: 1741
hardirqs last  enabled at (1741): [<ffffffff84d49d77>]
__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:160
[inline]
hardirqs last  enabled at (1741): [<ffffffff84d49d77>]
_raw_spin_unlock_irqrestore+0xf7/0x1a0 kernel/locking/spinlock.c:191
hardirqs last disabled at (1740): [<ffffffff84d4a732>]
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:108 [inline]
hardirqs last disabled at (1740): [<ffffffff84d4a732>]
_raw_spin_lock_irqsave+0xa2/0x110 kernel/locking/spinlock.c:159
softirqs last  enabled at (1738): [<ffffffff84d4deff>]
__do_softirq+0x7cf/0xb7d kernel/softirq.c:310
softirqs last disabled at (1571): [<ffffffff84d4b92c>]
do_softirq_own_stack+0x1c/0x30 arch/x86/entry/entry_64.S:902

other info that might help us debug this:
 Possible unsafe locking scenario:

       CPU0
       ----
  lock(&(&hashinfo->ehash_locks[i])->rlock);
  <Interrupt>
    lock(&(&hashinfo->ehash_locks[i])->rlock);

 *** DEADLOCK ***

1 lock held by syz-executor0/5090:
 #0:  (sk_lock-AF_INET6){+.+.+.}, at: [<ffffffff83406b43>] lock_sock
include/net/sock.h:1460 [inline]
 #0:  (sk_lock-AF_INET6){+.+.+.}, at: [<ffffffff83406b43>]
sock_setsockopt+0x233/0x1e40 net/core/sock.c:683

stack backtrace:
CPU: 1 PID: 5090 Comm: syz-executor0 Not tainted 4.10.0+ #60
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:15 [inline]
 dump_stack+0x292/0x398 lib/dump_stack.c:51
 print_usage_bug+0x3ef/0x450 kernel/locking/lockdep.c:2387
 valid_state kernel/locking/lockdep.c:2400 [inline]
 mark_lock_irq kernel/locking/lockdep.c:2602 [inline]
 mark_lock+0xf30/0x1410 kernel/locking/lockdep.c:3065
 mark_irqflags kernel/locking/lockdep.c:2941 [inline]
 __lock_acquire+0x6dc/0x3270 kernel/locking/lockdep.c:3295
 lock_acquire+0x241/0x580 kernel/locking/lockdep.c:3753
 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline]
 _raw_spin_lock+0x33/0x50 kernel/locking/spinlock.c:151
 spin_lock include/linux/spinlock.h:299 [inline]
 inet_ehash_insert+0x240/0xad0 net/ipv4/inet_hashtables.c:407
 reqsk_queue_hash_req net/ipv4/inet_connection_sock.c:753 [inline]
 inet_csk_reqsk_queue_hash_add+0x1b7/0x2a0 net/ipv4/inet_connection_sock.c:764
 dccp_v6_conn_request+0xada/0x11b0 net/dccp/ipv6.c:380
 dccp_rcv_state_process+0x51e/0x1660 net/dccp/input.c:606
 dccp_v6_do_rcv+0x213/0x350 net/dccp/ipv6.c:632
 sk_backlog_rcv include/net/sock.h:896 [inline]
 __release_sock+0x127/0x3a0 net/core/sock.c:2052
 release_sock+0xa5/0x2b0 net/core/sock.c:2539
 sock_setsockopt+0x60f/0x1e40 net/core/sock.c:1016
 SYSC_setsockopt net/socket.c:1782 [inline]
 SyS_setsockopt+0x2fb/0x3a0 net/socket.c:1765
 entry_SYSCALL_64_fastpath+0x1f/0xc2
RIP: 0033:0x4458b9
RSP: 002b:00007fe8b26c2b58 EFLAGS: 00000292 ORIG_RAX: 0000000000000036
RAX: ffffffffffffffda RBX: 0000000000000006 RCX: 00000000004458b9
RDX: 000000000000001a RSI: 0000000000000001 RDI: 0000000000000006
RBP: 00000000006e2110 R08: 0000000000000010 R09: 0000000000000000
R10: 00000000208c3000 R11: 0000000000000292 R12: 0000000000708000
R13: 0000000020000000 R14: 0000000000001000 R15: 0000000000000000

Fixes: 5413d1babe ("net: do not block BH while processing socket backlog")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Andrey Konovalov <andreyknvl@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-01 15:03:31 -08:00
Liping Zhang
3b45a4106f net: route: add missing nla_policy entry for RTA_MARK attribute
This will add stricter validating for RTA_MARK attribute.

Signed-off-by: Liping Zhang <zlpnobody@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-01 10:25:56 -08:00
Linus Torvalds
c2eca00fec Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:

 1) Don't save TIPC header values before the header has been validated,
    from Jon Paul Maloy.

 2) Fix memory leak in RDS, from Zhu Yanjun.

 3) We miss to initialize the UID in the flow key in some paths, from
    Julian Anastasov.

 4) Fix latent TOS masking bug in the routing cache removal from years
    ago, also from Julian.

 5) We forget to set the sockaddr port in sctp_copy_local_addr_list(),
    fix from Xin Long.

 6) Missing module ref count drop in packet scheduler actions, from
    Roman Mashak.

 7) Fix RCU annotations in rht_bucket_nested, from Herbert Xu.

 8) Fix use after free which happens because L2TP's ipv4 support returns
    non-zero values from it's backlog_rcv function which ipv4 interprets
    as protocol values. Fix from Paul Hüber.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (35 commits)
  qed: Don't use attention PTT for configuring BW
  qed: Fix race with multiple VFs
  l2tp: avoid use-after-free caused by l2tp_ip_backlog_recv
  xfrm: provide correct dst in xfrm_neigh_lookup
  rhashtable: Fix RCU dereference annotation in rht_bucket_nested
  rhashtable: Fix use before NULL check in bucket_table_free
  net sched actions: do not overwrite status of action creation.
  rxrpc: Kernel calls get stuck in recvmsg
  net sched actions: decrement module reference count after table flush.
  lib: Allow compile-testing of parman
  ipv6: check sk sk_type and protocol early in ip_mroute_set/getsockopt
  sctp: set sin_port for addr param when checking duplicate address
  net/mlx4_en: fix overflow in mlx4_en_init_timestamp()
  netfilter: nft_set_bitmap: incorrect bitmap size
  net: s2io: fix typo argumnet argument
  net: vxge: fix typo argumnet argument
  netfilter: nf_ct_expect: Change __nf_ct_expect_check() return value.
  ipv4: mask tos for input route
  ipv4: add missing initialization for flowi4_uid
  lib: fix spelling mistake: "actualy" -> "actually"
  ...
2017-02-28 10:00:39 -08:00
Florian Westphal
29e09229d9 netfilter: use skb_to_full_sk in ip_route_me_harder
inet_sk(skb->sk) is illegal in case skb is attached to request socket.

Fixes: ca6fb06518 ("tcp: attach SYNACK messages to request sockets instead of listener")
Reported by: Daniel J Blueman <daniel@quora.org>
Signed-off-by: Florian Westphal <fw@strlen.de>
Tested-by: Daniel J Blueman <daniel@quora.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-02-28 12:49:36 +01:00
Alexey Dobriyan
5b5e0928f7 lib/vsprintf.c: remove %Z support
Now that %z is standartised in C99 there is no reason to support %Z.
Unlike %L it doesn't even make format strings smaller.

Use BUILD_BUG_ON in a couple ATM drivers.

In case anyone didn't notice lib/vsprintf.o is about half of SLUB which
is in my opinion is quite an achievement.  Hopefully this patch inspires
someone else to trim vsprintf.c more.

Link: http://lkml.kernel.org/r/20170103230126.GA30170@avx2
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-27 18:43:47 -08:00
Julian Anastasov
6e28099d38 ipv4: mask tos for input route
Restore the lost masking of TOS in input route code to
allow ip rules to match it properly.

Problem [1] noticed by Shmulik Ladkani <shmulik.ladkani@gmail.com>

[1] http://marc.info/?t=137331755300040&r=1&w=2

Fixes: 89aef8921b ("ipv4: Delete routing cache.")
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-26 11:03:38 -05:00
Julian Anastasov
8bcfd0925e ipv4: add missing initialization for flowi4_uid
Avoid matching of random stack value for uid when rules
are looked up on input route or when RP filter is used.
Problem should affect only setups that use ip rules with
uid range.

Fixes: 622ec2c9d5 ("net: core: add UID to flows, rules, and routes")
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-26 11:03:38 -05:00
Alexey Kodanev
eee2faabc6 tcp: account for ts offset only if tsecr not zero
We can get SYN with zero tsecr, don't apply offset in this case.

Fixes: ee684b6f28 ("tcp: send packets with a socket timestamp")
Signed-off-by: Alexey Kodanev <alexey.kodanev@oracle.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-22 16:35:58 -05:00
Alexey Kodanev
00355fa5bb tcp: setup timestamp offset when write_seq already set
Found that when randomized tcp offsets are enabled (by default)
TCP client can still start new connections without them. Later,
if server does active close and re-uses sockets in TIME-WAIT
state, new SYN from client can be rejected on PAWS check inside
tcp_timewait_state_process(), because either tw_ts_recent or
rcv_tsval doesn't really have an offset set.

Here is how to reproduce it with LTP netstress tool:
    netstress -R 1 &
    netstress -H 127.0.0.1 -lr 1000000 -a1

    [...]
    < S  seq 1956977072 win 43690 TS val 295618 ecr 459956970
    > .  ack 1956911535 win 342 TS val 459967184 ecr 1547117608
    < R  seq 1956911535 win 0 length 0
+1. < S  seq 1956977072 win 43690 TS val 296640 ecr 459956970
    > S. seq 657450664 ack 1956977073 win 43690 TS val 459968205 ecr 296640

Fixes: 95a22caee3 ("tcp: randomize tcp timestamp offsets for each connection")
Signed-off-by: Alexey Kodanev <alexey.kodanev@oracle.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-22 16:35:32 -05:00
Eric Dumazet
29869d6687 tcp: Revert "tcp: tcp_probe: use spin_lock_bh()"
This reverts commit e70ac17165.

jtcp_rcv_established() is in fact called with hard irq being disabled.

Initial bug report from Ricardo Nabinger Sanchez [1] still needs
to be investigated, but does not look like a TCP bug.

[1] https://www.spinics.net/lists/netdev/msg420960.html

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: kernel test robot <xiaolong.ye@intel.com>
Cc: Ricardo Nabinger Sanchez <rnsanchez@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-21 13:26:03 -05:00
Paolo Abeni
ca4ef4574f ip: fix IP_CHECKSUM handling
The skbs processed by ip_cmsg_recv() are not guaranteed to
be linear e.g. when sending UDP packets over loopback with
MSGMORE.
Using csum_partial() on [potentially] the whole skb len
is dangerous; instead be on the safe side and use skb_checksum().

Thanks to syzkaller team to detect the issue and provide the
reproducer.

v1 -> v2:
 - move the variable declaration in a tighter scope

Fixes: ad6f939ab1 ("ip: Add offset parameter to ip_cmsg_recv")
Reported-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-21 12:23:53 -05:00
Eric Dumazet
4e33e34625 tcp: use page_ref_inc() in tcp_sendmsg()
sk_page_frag_refill() allocates either a compound page or an order-0
page. We can use page_ref_inc() which is slightly faster than get_page()

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-17 15:31:06 -05:00
Cui, Cheng
a4ecb15a24 tcp: accommodate sequence number to a peer's shrunk receive window caused by precision loss in window scaling
Prevent sending out a left-shifted sequence number from a Linux sender in
response to a peer's shrunk receive-window caused by losing least significant
bits in window-scaling.

Cc: "David S. Miller" <davem@davemloft.net>
Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
Cc: James Morris <jmorris@namei.org>
Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>
Cc: Patrick McHardy <kaber@trash.net>
Signed-off-by: Cheng Cui <Cheng.Cui@netapp.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-17 15:30:33 -05:00