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43011 commits

Author SHA1 Message Date
Eric Dumazet
76061f631c tcp: fastopen: avoid negative sk_forward_alloc
When DATA and/or FIN are carried in a SYN/ACK message or SYN message,
we append an skb in socket receive queue, but we forget to call
sk_forced_mem_schedule().

Effect is that the socket has a negative sk->sk_forward_alloc as long as
the message is not read by the application.

Josh Hunt fixed a similar issue in commit d22e153718 ("tcp: fix tcp
fin memory accounting")

Fixes: 168a8f5805 ("tcp: TCP Fast Open Server - main code path")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Josh Hunt <johunt@akamai.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-08 16:08:10 -07:00
David S. Miller
40e3012e6e Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec
Steffen Klassert says:

====================
ipsec 2016-09-08

1) Fix a crash when xfrm_dump_sa returns an error.
   From Vegard Nossum.

2) Remove some incorrect WARN() on normal error handling.
   From Vegard Nossum.

3) Ignore socket policies when rebuilding hash tables,
   socket policies are not inserted into the hash tables.
   From Tobias Brunner.

4) Initialize and check tunnel pointers properly before
   we use it. From Alexey Kodanev.

5) Fix l3mdev oif setting on xfrm dst lookups.
   From David Ahern.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-08 13:12:37 -07:00
Wei Yongjun
751eb6b604 ipv6: addrconf: fix dev refcont leak when DAD failed
In general, when DAD detected IPv6 duplicate address, ifp->state
will be set to INET6_IFADDR_STATE_ERRDAD and DAD is stopped by a
delayed work, the call tree should be like this:

ndisc_recv_ns
  -> addrconf_dad_failure        <- missing ifp put
     -> addrconf_mod_dad_work
       -> schedule addrconf_dad_work()
         -> addrconf_dad_stop()  <- missing ifp hold before call it

addrconf_dad_failure() called with ifp refcont holding but not put.
addrconf_dad_work() call addrconf_dad_stop() without extra holding
refcount. This will not cause any issue normally.

But the race between addrconf_dad_failure() and addrconf_dad_work()
may cause ifp refcount leak and netdevice can not be unregister,
dmesg show the following messages:

IPv6: eth0: IPv6 duplicate address fe80::XX:XXXX:XXXX:XX detected!
...
unregister_netdevice: waiting for eth0 to become free. Usage count = 1

Cc: stable@vger.kernel.org
Fixes: c15b1ccadb ("ipv6: move DAD and addrconf_verify processing
to workqueue")
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-06 14:17:49 -07:00
Mark Tomlinson
5a56a0b3a4 net: Don't delete routes in different VRFs
When deleting an IP address from an interface, there is a clean-up of
routes which refer to this local address. However, there was no check to
see that the VRF matched. This meant that deletion wasn't confined to
the VRF it should have been.

To solve this, a new field has been added to fib_info to hold a table
id. When removing fib entries corresponding to a local ip address, this
table id is also used in the comparison.

The table id is populated when the fib_info is created. This was already
done in some places, but not in ip_rt_ioctl(). This has now been fixed.

Fixes: 021dd3b8a1 ("net: Add routes to the table associated with the device")
Acked-by: David Ahern <dsa@cumulusnetworks.com>
Tested-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: Mark Tomlinson <mark.tomlinson@alliedtelesis.co.nz>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-06 13:56:13 -07:00
Dave Jones
03c2778a93 ipv6: release dst in ping_v6_sendmsg
Neither the failure or success paths of ping_v6_sendmsg release
the dst it acquires.  This leads to a flood of warnings from
"net/core/dst.c:288 dst_release" on older kernels that
don't have 8bf4ada2e2 backported.

That patch optimistically hoped this had been fixed post 3.10, but
it seems at least one case wasn't, where I've seen this triggered
a lot from machines doing unprivileged icmp sockets.

Cc: Martin Lau <kafai@fb.com>
Signed-off-by: Dave Jones <davej@codemonkey.org.uk>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-06 12:54:17 -07:00
6e1ce3c345 af_unix: split 'u->readlock' into two: 'iolock' and 'bindlock'
Right now we use the 'readlock' both for protecting some of the af_unix
IO path and for making the bind be single-threaded.

The two are independent, but using the same lock makes for a nasty
deadlock due to ordering with regards to filesystem locking.  The bind
locking would want to nest outside the VSF pathname locking, but the IO
locking wants to nest inside some of those same locks.

We tried to fix this earlier with commit c845acb324 ("af_unix: Fix
splice-bind deadlock") which moved the readlock inside the vfs locks,
but that caused problems with overlayfs that will then call back into
filesystem routines that take the lock in the wrong order anyway.

Splitting the locks means that we can go back to having the bind lock be
the outermost lock, and we don't have any deadlocks with lock ordering.

Acked-by: Rainer Weikusat <rweikusat@cyberadapt.com>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-04 13:29:29 -07:00
38f7bd94a9 Revert "af_unix: Fix splice-bind deadlock"
This reverts commit c845acb324.

It turns out that it just replaces one deadlock with another one: we can
still get the wrong lock ordering with the readlock due to overlayfs
calling back into the filesystem layer and still taking the vfs locks
after the readlock.

The proper solution ends up being to just split the readlock into two
pieces: the bind lock (taken *outside* the vfs locks) and the IO lock
(taken *inside* the filesystem locks).  The two locks are independent
anyway.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Reviewed-by: Shmulik Ladkani <shmulik.ladkani@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-04 13:29:29 -07:00
Mahesh Bandewar
24b27fc4cd bonding: Fix bonding crash
Following few steps will crash kernel -

  (a) Create bonding master
      > modprobe bonding miimon=50
  (b) Create macvlan bridge on eth2
      > ip link add link eth2 dev mvl0 address aa:0:0:0:0:01 \
	   type macvlan
  (c) Now try adding eth2 into the bond
      > echo +eth2 > /sys/class/net/bond0/bonding/slaves
      <crash>

Bonding does lots of things before checking if the device enslaved is
busy or not.

In this case when the notifier call-chain sends notifications, the
bond_netdev_event() assumes that the rx_handler /rx_handler_data is
registered while the bond_enslave() hasn't progressed far enough to
register rx_handler for the new slave.

This patch adds a rx_handler check that can be performed right at the
beginning of the enslave code to avoid getting into this situation.

Signed-off-by: Mahesh Bandewar <maheshb@google.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-04 11:41:12 -07:00
Sabrina Dubroca
2f86953e74 l2tp: fix use-after-free during module unload
Tunnel deletion is delayed by both a workqueue (l2tp_tunnel_delete -> wq
 -> l2tp_tunnel_del_work) and RCU (sk_destruct -> RCU ->
l2tp_tunnel_destruct).

By the time l2tp_tunnel_destruct() runs to destroy the tunnel and finish
destroying the socket, the private data reserved via the net_generic
mechanism has already been freed, but l2tp_tunnel_destruct() actually
uses this data.

Make sure tunnel deletion for the netns has completed before returning
from l2tp_exit_net() by first flushing the tunnel removal workqueue, and
then waiting for RCU callbacks to complete.

Fixes: 167eb17e0b ("l2tp: create tunnel sockets in the right namespace")
Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-02 11:44:44 -07:00
Eli Cooper
ab34380162 ipv6: Don't unset flowi6_proto in ipxip6_tnl_xmit()
Commit 8eb30be035 ("ipv6: Create ip6_tnl_xmit") unsets
flowi6_proto in ip4ip6_tnl_xmit() and ip6ip6_tnl_xmit().
Since xfrm_selector_match() relies on this info, IPv6 packets
sent by an ip6tunnel cannot be properly selected by their
protocols after removing it. This patch puts flowi6_proto back.

Cc: stable@vger.kernel.org
Fixes: 8eb30be035 ("ipv6: Create ip6_tnl_xmit")
Signed-off-by: Eli Cooper <elicooper@gmx.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-01 23:41:24 -07:00
Gao Feng
635c223cfa rps: flow_dissector: Fix uninitialized flow_keys used in __skb_get_hash possibly
The original codes depend on that the function parameters are evaluated from
left to right. But the parameter's evaluation order is not defined in C
standard actually.

When flow_keys_have_l4(&keys) is invoked before ___skb_get_hash(skb, &keys,
hashrnd) with some compilers or environment, the keys passed to
flow_keys_have_l4 is not initialized.

Fixes: 6db61d79c1 ("flow_dissector: Ignore flow dissector return value from ___skb_get_hash")

Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Gao Feng <fgao@ikuai8.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-01 22:45:03 -07:00
Neal Cardwell
28b346cbc0 tcp: fastopen: fix rcv_wup initialization for TFO server on SYN/data
Yuchung noticed that on the first TFO server data packet sent after
the (TFO) handshake, the server echoed the TCP timestamp value in the
SYN/data instead of the timestamp value in the final ACK of the
handshake. This problem did not happen on regular opens.

The tcp_replace_ts_recent() logic that decides whether to remember an
incoming TS value needs tp->rcv_wup to hold the latest receive
sequence number that we have ACKed (latest tp->rcv_nxt we have
ACKed). This commit fixes this issue by ensuring that a TFO server
properly updates tp->rcv_wup to match tp->rcv_nxt at the time it sends
a SYN/ACK for the SYN/data.

Reported-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com>
Fixes: 168a8f5805 ("tcp: TCP Fast Open Server - main code path")
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-01 16:40:15 -07:00
Nikolay Aleksandrov
85a3d4a935 net: bridge: don't increment tx_dropped in br_do_proxy_arp
pskb_may_pull may fail due to various reasons (e.g. alloc failure), but the
skb isn't changed/dropped and processing continues so we shouldn't
increment tx_dropped.

CC: Kyeyoon Park <kyeyoonp@codeaurora.org>
CC: Roopa Prabhu <roopa@cumulusnetworks.com>
CC: Stephen Hemminger <stephen@networkplumber.org>
CC: bridge@lists.linux-foundation.org
Fixes: 958501163d ("bridge: Add support for IEEE 802.11 Proxy ARP")
Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-01 16:35:30 -07:00
Nicolas Dichtel
29c994e361 netconf: add a notif when settings are created
All changes are notified, but the initial state was missing.

Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-01 15:18:08 -07:00
Nicolas Dichtel
d26c638c16 ipv6: add missing netconf notif when 'all' is updated
The 'default' value was not advertised.

Fixes: f3a1bfb11c ("rtnl/ipv6: use netconf msg to advertise forwarding status")
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-01 15:18:08 -07:00
Parthasarathy Bhuvaragan
d2f394dc48 tipc: fix random link resets while adding a second bearer
In a dual bearer configuration, if the second tipc link becomes
active while the first link still has pending nametable "bulk"
updates, it randomly leads to reset of the second link.

When a link is established, the function named_distribute(),
fills the skb based on node mtu (allows room for TUNNEL_PROTOCOL)
with NAME_DISTRIBUTOR message for each PUBLICATION.
However, the function named_distribute() allocates the buffer by
increasing the node mtu by INT_H_SIZE (to insert NAME_DISTRIBUTOR).
This consumes the space allocated for TUNNEL_PROTOCOL.

When establishing the second link, the link shall tunnel all the
messages in the first link queue including the "bulk" update.
As size of the NAME_DISTRIBUTOR messages while tunnelling, exceeds
the link mtu the transmission fails (-EMSGSIZE).

Thus, the synch point based on the message count of the tunnel
packets is never reached leading to link timeout.

In this commit, we adjust the size of name distributor message so that
they can be tunnelled.

Reviewed-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: Parthasarathy Bhuvaragan <parthasarathy.bhuvaragan@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-01 10:12:26 -07:00
WANG Cong
c0338aff22 kcm: fix a socket double free
Dmitry reported a double free on kcm socket, which could
be easily reproduced by:

	#include <unistd.h>
	#include <sys/syscall.h>

	int main()
	{
	  int fd = syscall(SYS_socket, 0x29ul, 0x5ul, 0x0ul, 0, 0, 0);
	  syscall(SYS_ioctl, fd, 0x89e2ul, 0x20a98000ul, 0, 0, 0);
	  return 0;
	}

This is because on the error path, after we install
the new socket file, we call sock_release() to clean
up the socket, which leaves the fd pointing to a freed
socket. Fix this by calling sys_close() on that fd
directly.

Fixes: ab7ac4eb98 ("kcm: Kernel Connection Multiplexor module")
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Tom Herbert <tom@herbertland.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-31 21:00:19 -07:00
Davide Caratti
9264251ee2 bridge: re-introduce 'fix parsing of MLDv2 reports'
commit bc8c20acae ("bridge: multicast: treat igmpv3 report with
INCLUDE and no sources as a leave") seems to have accidentally reverted
commit 47cc84ce0c ("bridge: fix parsing of MLDv2 reports"). This
commit brings back a change to br_ip6_multicast_mld2_report() where
parsing of MLDv2 reports stops when the first group is successfully
added to the MDB cache.

Fixes: bc8c20acae ("bridge: multicast: treat igmpv3 report with INCLUDE and no sources as a leave")
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Acked-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Acked-by: Thadeu Lima de Souza Cascardo <cascardo@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-31 09:29:58 -07:00
David S. Miller
2df5d103a6 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) Allow nf_tables reject expression from input, forward and output hooks,
   since only there the routing information is available, otherwise we crash.

2) Fix unsafe list iteration when flushing timeout and accouting objects.

3) Fix refcount leak on timeout policy parsing failure.

4) Unlink timeout object for unconfirmed conntracks too

5) Missing validation of pkttype mangling from bridge family.

6) Fix refcount leak on ebtables on second lookup for the specific
   bridge match extension, this patch from Sabrina Dubroca.

7) Remove unnecessary ip_hdr() in nf_tables_netdev family.

Patches from 1-5 and 7 from Liping Zhang.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-30 22:02:09 -07:00
David S. Miller
15543692a0 Three little fixes:
* revert a recent wext patch, which Ben Hutchings noticed was
    wrong, and it turns out not to be necessary for any driver
 
  * fix an infinite loop that can occur under certain conditions
    in mac80211's TDLS code (depending on regulatory information)
 
  * add a cfg80211_get_station() static inline when cfg80211 isn't
    built, to allow other modules to not have to depend on it for it
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Merge tag 'mac80211-for-davem-2016-08-30' of git://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211

Johannes Berg says:

====================
Three little fixes:
 * revert a recent wext patch, which Ben Hutchings noticed was
   wrong, and it turns out not to be necessary for any driver

 * fix an infinite loop that can occur under certain conditions
   in mac80211's TDLS code (depending on regulatory information)

 * add a cfg80211_get_station() static inline when cfg80211 isn't
   built, to allow other modules to not have to depend on it for it
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-30 21:34:48 -07:00
Liping Zhang
c73c248490 netfilter: nf_tables_netdev: remove redundant ip_hdr assignment
We have already use skb_header_pointer to get the ip header pointer,
so there's no need to use ip_hdr again. Moreover, in NETDEV INGRESS
hook, ip header maybe not linear, so use ip_hdr is not appropriate,
remove it.

Signed-off-by: Liping Zhang <liping.zhang@spreadtrum.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-08-30 11:41:04 +02:00
Arik Nemtsov
554d072e7b mac80211: TDLS: don't require beaconing for AP BW
Stop downgrading TDLS chandef when reaching the AP BW. The AP provides
the necessary regulatory protection in this case.

This fixes https://bugzilla.kernel.org/show_bug.cgi?id=153961, which
reported an infinite loop here.

Reported-by: Kamil Toman <kamil.toman@gmail.com>
Signed-off-by: Arik Nemtsov <arikx.nemtsov@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2016-08-30 08:03:41 +02:00
David S. Miller
5c1f5b457b Merge branch 'for-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/bluetooth/bluetooth
Johan Hedberg says:

====================
pull request: bluetooth 2016-08-25

Here are a couple of important Bluetooth fixes for the 4.8 kernel:

 - Memory leak fix for HCI requests
 - Fix sk_filter handling with L2CAP
 - Fix sock_recvmsg behavior when MSG_TRUNC is not set

Please let me know if there are any issues pulling. Thanks.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-26 21:09:17 -07:00
Eric Dumazet
166ee5b878 qdisc: fix a module refcount leak in qdisc_create_dflt()
Should qdisc_alloc() fail, we must release the module refcount
we got right before.

Fixes: 6da7c8fcbc ("qdisc: allow setting default queuing discipline")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: John Fastabend <john.r.fastabend@intel.com>
Acked-by: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-25 16:44:20 -07:00
Wei Yongjun
a5de125dd4 tipc: fix the error handling in tipc_udp_enable()
Fix to return a negative error code in enable_mcast() error handling
case, and release udp socket when necessary.

Fixes: d0f91938be ("tipc: add ip/udp media type")
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-25 16:32:34 -07:00
Luiz Augusto von Dentz
4f34228b67 Bluetooth: Fix hci_sock_recvmsg when MSG_TRUNC is not set
Similar to bt_sock_recvmsg MSG_TRUNC shall be checked using the original
flags not msg_flags.

Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2016-08-25 20:58:47 +02:00
Luiz Augusto von Dentz
90a56f72ed Bluetooth: Fix bt_sock_recvmsg when MSG_TRUNC is not set
Commit b5f34f9420 attempt to introduce
proper handling for MSG_TRUNC but recv and variants should still work
as read if no flag is passed, but because the code may set MSG_TRUNC to
msg->msg_flags that shall not be used as it may cause it to be behave as
if MSG_TRUNC is always, so instead of using it this changes the code to
use the flags parameter which shall contain the original flags.

Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2016-08-25 20:58:47 +02:00
Sabrina Dubroca
4249fc1f02 netfilter: ebtables: put module reference when an incorrect extension is found
commit bcf4934288 ("netfilter: ebtables: Fix extension lookup with
identical name") added a second lookup in case the extension that was
found during the first lookup matched another extension with the same
name, but didn't release the reference on the incorrect module.

Fixes: bcf4934288 ("netfilter: ebtables: Fix extension lookup with identical name")
Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Acked-by: Phil Sutter <phil@nwl.cc>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-08-25 13:18:06 +02:00
Liping Zhang
960fa72f67 netfilter: nft_meta: improve the validity check of pkttype set expr
"meta pkttype set" is only supported on prerouting chain with bridge
family and ingress chain with netdev family.

But the validate check is incomplete, and the user can add the nft
rules on input chain with bridge family, for example:
  # nft add table bridge filter
  # nft add chain bridge filter input {type filter hook input \
    priority 0 \;}
  # nft add chain bridge filter test
  # nft add rule bridge filter test meta pkttype set unicast
  # nft add rule bridge filter input jump test

This patch fixes the problem.

Signed-off-by: Liping Zhang <liping.zhang@spreadtrum.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-08-25 13:12:03 +02:00
Liping Zhang
533e330098 netfilter: cttimeout: unlink timeout objs in the unconfirmed ct lists
KASAN reported this bug:
  BUG: KASAN: use-after-free in icmp_packet+0x25/0x50 [nf_conntrack_ipv4] at
  addr ffff880002db08c8
  Read of size 4 by task lt-nf-queue/19041
  Call Trace:
  <IRQ>  [<ffffffff815eeebb>] dump_stack+0x63/0x88
  [<ffffffff813386f8>] kasan_report_error+0x528/0x560
  [<ffffffff81338cc8>] kasan_report+0x58/0x60
  [<ffffffffa07393f5>] ? icmp_packet+0x25/0x50 [nf_conntrack_ipv4]
  [<ffffffff81337551>] __asan_load4+0x61/0x80
  [<ffffffffa07393f5>] icmp_packet+0x25/0x50 [nf_conntrack_ipv4]
  [<ffffffffa06ecaa0>] nf_conntrack_in+0x550/0x980 [nf_conntrack]
  [<ffffffffa06ec550>] ? __nf_conntrack_confirm+0xb10/0xb10 [nf_conntrack]
  [ ... ]

The main reason is that we missed to unlink the timeout objects in the
unconfirmed ct lists, so we will access the timeout objects that have
already been freed.

Signed-off-by: Liping Zhang <liping.zhang@spreadtrum.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-08-25 13:11:30 +02:00
Liping Zhang
23aaba5ad5 netfilter: cttimeout: put back l4proto when replacing timeout policy
We forget to call nf_ct_l4proto_put when replacing the existing
timeout policy. Acctually, there's no need to get ct l4proto
before doing replace, so we can move it to a later position.

Signed-off-by: Liping Zhang <liping.zhang@spreadtrum.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-08-25 13:11:16 +02:00
Liping Zhang
93fac10b99 netfilter: nfnetlink: use list_for_each_entry_safe to delete all objects
cttimeout and acct objects are deleted from the list while traversing
it, so use list_for_each_entry is unsafe here.

Signed-off-by: Liping Zhang <liping.zhang@spreadtrum.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-08-25 13:11:00 +02:00
Liping Zhang
89e1f6d2b9 netfilter: nft_reject: restrict to INPUT/FORWARD/OUTPUT
After I add the nft rule "nft add rule filter prerouting reject
with tcp reset", kernel panic happened on my system:
  NULL pointer dereference at ...
  IP: [<ffffffff81b9db2f>] nf_send_reset+0xaf/0x400
  Call Trace:
  [<ffffffff81b9da80>] ? nf_reject_ip_tcphdr_get+0x160/0x160
  [<ffffffffa0928061>] nft_reject_ipv4_eval+0x61/0xb0 [nft_reject_ipv4]
  [<ffffffffa08e836a>] nft_do_chain+0x1fa/0x890 [nf_tables]
  [<ffffffffa08e8170>] ? __nft_trace_packet+0x170/0x170 [nf_tables]
  [<ffffffffa06e0900>] ? nf_ct_invert_tuple+0xb0/0xc0 [nf_conntrack]
  [<ffffffffa07224d4>] ? nf_nat_setup_info+0x5d4/0x650 [nf_nat]
  [...]

Because in the PREROUTING chain, routing information is not exist,
then we will dereference the NULL pointer and oops happen.

So we restrict reject expression to INPUT, FORWARD and OUTPUT chain.
This is consistent with iptables REJECT target.

Signed-off-by: Liping Zhang <liping.zhang@spreadtrum.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-08-25 12:55:34 +02:00
Daniel Borkmann
dbb50887c8 Bluetooth: split sk_filter in l2cap_sock_recv_cb
During an audit for sk_filter(), we found that rx_busy_skb handling
in l2cap_sock_recv_cb() and l2cap_sock_recvmsg() looks not quite as
intended.

The assumption from commit e328140fda ("Bluetooth: Use event-driven
approach for handling ERTM receive buffer") is that errors returned
from sock_queue_rcv_skb() are due to receive buffer shortage. However,
nothing should prevent doing a setsockopt() with SO_ATTACH_FILTER on
the socket, that could drop some of the incoming skbs when handled in
sock_queue_rcv_skb().

In that case sock_queue_rcv_skb() will return with -EPERM, propagated
from sk_filter() and if in L2CAP_MODE_ERTM mode, wrong assumption was
that we failed due to receive buffer being full. From that point onwards,
due to the to-be-dropped skb being held in rx_busy_skb, we cannot make
any forward progress as rx_busy_skb is never cleared from l2cap_sock_recvmsg(),
due to the filter drop verdict over and over coming from sk_filter().
Meanwhile, in l2cap_sock_recv_cb() all new incoming skbs are being
dropped due to rx_busy_skb being occupied.

Instead, just use __sock_queue_rcv_skb() where an error really tells that
there's a receive buffer issue. Split the sk_filter() and enable it for
non-segmented modes at queuing time since at this point in time the skb has
already been through the ERTM state machine and it has been acked, so dropping
is not allowed. Instead, for ERTM and streaming mode, call sk_filter() in
l2cap_data_rcv() so the packet can be dropped before the state machine sees it.

Fixes: e328140fda ("Bluetooth: Use event-driven approach for handling ERTM receive buffer")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Acked-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2016-08-24 16:55:04 +02:00
Frederic Dalleau
9afee94939 Bluetooth: Fix memory leak at end of hci requests
In hci_req_sync_complete the event skb is referenced in hdev->req_skb.
It is used (via hci_req_run_skb) from either __hci_cmd_sync_ev which will
pass the skb to the caller, or __hci_req_sync which leaks.

unreferenced object 0xffff880005339a00 (size 256):
  comm "kworker/u3:1", pid 1011, jiffies 4294671976 (age 107.389s)
  backtrace:
    [<ffffffff818d89d9>] kmemleak_alloc+0x49/0xa0
    [<ffffffff8116bba8>] kmem_cache_alloc+0x128/0x180
    [<ffffffff8167c1df>] skb_clone+0x4f/0xa0
    [<ffffffff817aa351>] hci_event_packet+0xc1/0x3290
    [<ffffffff8179a57b>] hci_rx_work+0x18b/0x360
    [<ffffffff810692ea>] process_one_work+0x14a/0x440
    [<ffffffff81069623>] worker_thread+0x43/0x4d0
    [<ffffffff8106ead4>] kthread+0xc4/0xe0
    [<ffffffff818dd38f>] ret_from_fork+0x1f/0x40
    [<ffffffffffffffff>] 0xffffffffffffffff

Signed-off-by: Frédéric Dalleau <frederic.dalleau@collabora.co.uk>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2016-08-24 16:49:29 +02:00
David Ahern
d7226c7a4d net: diag: Fix refcnt leak in error path destroying socket
inet_diag_find_one_icsk takes a reference to a socket that is not
released if sock_diag_destroy returns an error. Fix by changing
tcp_diag_destroy to manage the refcnt for all cases and remove
the sock_put calls from tcp_abort.

Fixes: c1e64e298b ("net: diag: Support destroying TCP sockets")
Reported-by: Lorenzo Colitti <lorenzo@google.com>
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-23 23:11:36 -07:00
Eric Dumazet
75d855a5e9 udp: get rid of SLAB_DESTROY_BY_RCU allocations
After commit ca065d0cf8 ("udp: no longer use SLAB_DESTROY_BY_RCU")
we do not need this special allocation mode anymore, even if it is
harmless.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-23 17:46:17 -07:00
Lance Richardson
232cb53a45 sctp: fix overrun in sctp_diag_dump_one()
The function sctp_diag_dump_one() currently performs a memcpy()
of 64 bytes from a 16 byte field into another 16 byte field. Fix
by using correct size, use sizeof to obtain correct size instead
of using a hard-coded constant.

Fixes: 8f840e47f1 ("sctp: add the sctp_diag.c file")
Signed-off-by: Lance Richardson <lrichard@redhat.com>
Reviewed-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-23 17:22:53 -07:00
Eric Dumazet
20a2b49fc5 tcp: properly scale window in tcp_v[46]_reqsk_send_ack()
When sending an ack in SYN_RECV state, we must scale the offered
window if wscale option was negotiated and accepted.

Tested:
 Following packetdrill test demonstrates the issue :

0.000 socket(..., SOCK_STREAM, IPPROTO_TCP) = 3
+0 setsockopt(3, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 0

+0 bind(3, ..., ...) = 0
+0 listen(3, 1) = 0

// Establish a connection.
+0 < S 0:0(0) win 20000 <mss 1000,sackOK,wscale 7, nop, TS val 100 ecr 0>
+0 > S. 0:0(0) ack 1 win 28960 <mss 1460,sackOK, TS val 100 ecr 100, nop, wscale 7>

+0 < . 1:11(10) ack 1 win 156 <nop,nop,TS val 99 ecr 100>
// check that window is properly scaled !
+0 > . 1:1(0) ack 1 win 226 <nop,nop,TS val 200 ecr 100>

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Yuchung Cheng <ycheng@google.com>
Cc: Neal Cardwell <ncardwell@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>
2016-08-23 16:55:49 -07:00
Eric Dumazet
e83c6744e8 udp: fix poll() issue with zero sized packets
Laura tracked poll() [and friends] regression caused by commit
e6afc8ace6 ("udp: remove headers from UDP packets before queueing")

udp_poll() needs to know if there is a valid packet in receive queue,
even if its payload length is 0.

Change first_packet_length() to return an signed int, and use -1
as the indication of an empty queue.

Fixes: e6afc8ace6 ("udp: remove headers from UDP packets before queueing")
Reported-by: Laura Abbott <labbott@redhat.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Tested-by: Laura Abbott <labbott@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-23 16:39:14 -07:00
Jamal Hadi Salim
28a10c426e net sched: fix encoding to use real length
Encoding of the metadata was using the padded length as opposed to
the real length of the data which is a bug per specification.
This has not been an issue todate because all metadatum specified
so far has been 32 bit where aligned and data length are the same width.
This also includes a bug fix for validating the length of a u16 field.
But since there is no metadata of size u16 yes we are fine to include it
here.

While at it get rid of magic numbers.

Fixes: ef6980b6be ("net sched: introduce IFE action")
Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-22 21:01:57 -07:00
Shmulik Ladkani
c0451fe1f2 net: ip_finish_output_gso: Allow fragmenting segments of tunneled skbs if their DF is unset
In b8247f095e,

   "net: ip_finish_output_gso: If skb_gso_network_seglen exceeds MTU, allow segmentation for local udp tunneled skbs"

gso skbs arriving from an ingress interface that go through UDP
tunneling, are allowed to be fragmented if the resulting encapulated
segments exceed the dst mtu of the egress interface.

This aligned the behavior of gso skbs to non-gso skbs going through udp
encapsulation path.

However the non-gso vs gso anomaly is present also in the following
cases of a GRE tunnel:
 - ip_gre in collect_md mode, where TUNNEL_DONT_FRAGMENT is not set
   (e.g. OvS vport-gre with df_default=false)
 - ip_gre in nopmtudisc mode, where IFLA_GRE_IGNORE_DF is set

In both of the above cases, the non-gso skbs get fragmented, whereas the
gso skbs (having skb_gso_network_seglen that exceeds dst mtu) get dropped,
as they don't go through the segment+fragment code path.

Fix: Setting IPSKB_FRAG_SEGS if the tunnel specified IP_DF bit is NOT set.

Tunnels that do set IP_DF, will not go to fragmentation of segments.
This preserves behavior of ip_gre in (the default) pmtudisc mode.

Fixes: b8247f095e ("net: ip_finish_output_gso: If skb_gso_network_seglen exceeds MTU, allow segmentation for local udp tunneled skbs")
Reported-by: wenxu <wenxu@ucloud.cn>
Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: Shmulik Ladkani <shmulik.ladkani@gmail.com>
Tested-by: wenxu <wenxu@ucloud.cn>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-22 17:11:01 -07:00
Mike Manning
85b51b1211 net: ipv6: Remove addresses for failures with strict DAD
If DAD fails with accept_dad set to 2, global addresses and host routes
are incorrectly left in place. Even though disable_ipv6 is set,
contrary to documentation, the addresses are not dynamically deleted
from the interface. It is only on a subsequent link down/up that these
are removed. The fix is not only to set the disable_ipv6 flag, but
also to call addrconf_ifdown(), which is the action to carry out when
disabling IPv6. This results in the addresses and routes being deleted
immediately. The DAD failure for the LL addr is determined as before
via netlink, or by the absence of the LL addr (which also previously
would have had to be checked for in case of an intervening link down
and up). As the call to addrconf_ifdown() requires an rtnl lock, the
logic to disable IPv6 when DAD fails is moved to addrconf_dad_work().

Previous behavior:

root@vm1:/# sysctl net.ipv6.conf.eth3.accept_dad=2
net.ipv6.conf.eth3.accept_dad = 2
root@vm1:/# ip -6 addr add 2000::10/64 dev eth3
root@vm1:/# ip link set up eth3
root@vm1:/# ip -6 addr show dev eth3
5: eth3: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qlen 1000
    inet6 2000::10/64 scope global
       valid_lft forever preferred_lft forever
    inet6 fe80::5054:ff:fe43:dd5a/64 scope link tentative dadfailed
       valid_lft forever preferred_lft forever
root@vm1:/# ip -6 route show dev eth3
2000::/64  proto kernel  metric 256
fe80::/64  proto kernel  metric 256
root@vm1:/# ip link set down eth3
root@vm1:/# ip link set up eth3
root@vm1:/# ip -6 addr show dev eth3
root@vm1:/# ip -6 route show dev eth3
root@vm1:/#

New behavior:

root@vm1:/# sysctl net.ipv6.conf.eth3.accept_dad=2
net.ipv6.conf.eth3.accept_dad = 2
root@vm1:/# ip -6 addr add 2000::10/64 dev eth3
root@vm1:/# ip link set up eth3
root@vm1:/# ip -6 addr show dev eth3
root@vm1:/# ip -6 route show dev eth3
root@vm1:/#

Signed-off-by: Mike Manning <mmanning@brocade.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-22 16:59:37 -07:00
David Ahern
11d7a0bb95 xfrm: Only add l3mdev oif to dst lookups
Subash reported that commit 42a7b32b73 ("xfrm: Add oif to dst lookups")
broke a wifi use case that uses fib rules and xfrms. The intent of
42a7b32b73 was driven by VRFs with IPsec. As a compromise relax the
use of oif in xfrm lookups to L3 master devices only (ie., oif is either
an L3 master device or is enslaved to a master device).

Fixes: 42a7b32b73 ("xfrm: Add oif to dst lookups")
Reported-by: Subash Abhinov Kasiviswanathan <subashab@codeaurora.org>
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2016-08-22 06:33:32 +02:00
Gao Feng
56cff471d0 l2tp: Fix the connect status check in pppol2tp_getname
The sk->sk_state is bits flag, so need use bit operation check
instead of value check.

Signed-off-by: Gao Feng <fgao@ikuai8.com>
Tested-by: Guillaume Nault <g.nault@alphalink.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-19 17:55:43 -07:00
Marcelo Ricardo Leitner
4c2f245496 sctp: linearize early if it's not GSO
Because otherwise when crc computation is still needed it's way more
expensive than on a linear buffer to the point that it affects
performance.

It's so expensive that netperf test gives a perf output as below:

Overhead  Command         Shared Object       Symbol
  18,62%  netserver       [kernel.vmlinux]    [k] crc32_generic_shift
   2,57%  netserver       [kernel.vmlinux]    [k] __pskb_pull_tail
   1,94%  netserver       [kernel.vmlinux]    [k] fib_table_lookup
   1,90%  netserver       [kernel.vmlinux]    [k] copy_user_enhanced_fast_string
   1,66%  swapper         [kernel.vmlinux]    [k] intel_idle
   1,63%  netserver       [kernel.vmlinux]    [k] _raw_spin_lock
   1,59%  netserver       [sctp]              [k] sctp_packet_transmit
   1,55%  netserver       [kernel.vmlinux]    [k] memcpy_erms
   1,42%  netserver       [sctp]              [k] sctp_rcv

# netperf -H 192.168.10.1 -l 10 -t SCTP_STREAM -cC -- -m 12000
SCTP STREAM TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 192.168.10.1 () port 0 AF_INET
Recv   Send    Send                          Utilization       Service Demand
Socket Socket  Message  Elapsed              Send     Recv     Send    Recv
Size   Size    Size     Time     Throughput  local    remote   local   remote
bytes  bytes   bytes    secs.    10^6bits/s  % S      % S      us/KB   us/KB

212992 212992  12000    10.00      3016.42   2.88     3.78     1.874   2.462

After patch:
Overhead  Command         Shared Object      Symbol
   2,75%  netserver       [kernel.vmlinux]   [k] memcpy_erms
   2,63%  netserver       [kernel.vmlinux]   [k] copy_user_enhanced_fast_string
   2,39%  netserver       [kernel.vmlinux]   [k] fib_table_lookup
   2,04%  netserver       [kernel.vmlinux]   [k] __pskb_pull_tail
   1,91%  netserver       [kernel.vmlinux]   [k] _raw_spin_lock
   1,91%  netserver       [sctp]             [k] sctp_packet_transmit
   1,72%  netserver       [mlx4_en]          [k] mlx4_en_process_rx_cq
   1,68%  netserver       [sctp]             [k] sctp_rcv

# netperf -H 192.168.10.1 -l 10 -t SCTP_STREAM -cC -- -m 12000
SCTP STREAM TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 192.168.10.1 () port 0 AF_INET
Recv   Send    Send                          Utilization       Service Demand
Socket Socket  Message  Elapsed              Send     Recv     Send    Recv
Size   Size    Size     Time     Throughput  local    remote   local   remote
bytes  bytes   bytes    secs.    10^6bits/s  % S      % S      us/KB   us/KB

212992 212992  12000    10.00      3681.77   3.83     3.46     2.045   1.849

Fixes: 3acb50c18d ("sctp: delay as much as possible skb_linearize")
Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-19 17:09:42 -07:00
Xunlei Pang
98a384eca9 fib_trie: Fix the description of pos and bits
1) Fix one typo: s/tn/tp/
2) Fix the description about the "u" bits.

Signed-off-by: Xunlei Pang <xlpang@redhat.com>
Acked-by: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-18 23:51:23 -07:00
David S. Miller
53409afd3e 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 updates for your net tree,
they are:

1) Dump only conntrack that belong to this namespace via /proc file.
   This is some fallout from the conversion to single conntrack table
   for all netns, patch from Liping Zhang.

2) Missing MODULE_ALIAS_NF_LOGGER() for the ARP family that prevents
   module autoloading, also from Liping Zhang.

3) Report overquota event to the right netnamespace, again from Liping.

4) Fix tproxy listener sk refcount that leads to crash, from
   Eric Dumazet.

5) Fix racy refcounting on object deletion from nfnetlink and rule
   removal both for nfacct and cttimeout, from Liping Zhang.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-18 18:45:34 -07:00
Liping Zhang
b75911b66a netfilter: cttimeout: fix use after free error when delete netns
In general, when we want to delete a netns, cttimeout_net_exit will
be called before ipt_unregister_table, i.e. before ctnl_timeout_put.

But after call kfree_rcu in cttimeout_net_exit, we will still decrease
the timeout object's refcnt in ctnl_timeout_put, this is incorrect,
and will cause a use after free error.

It is easy to reproduce this problem:
  # while : ; do
  ip netns add xxx
  ip netns exec xxx nfct add timeout testx inet icmp timeout 200
  ip netns exec xxx iptables -t raw -p icmp -I OUTPUT -j CT --timeout testx
  ip netns del xxx
  done

  =======================================================================
  BUG kmalloc-96 (Tainted: G    B       E  ): Poison overwritten
  -----------------------------------------------------------------------
  INFO: 0xffff88002b5161e8-0xffff88002b5161e8. First byte 0x6a instead of
  0x6b
  INFO: Allocated in cttimeout_new_timeout+0xd4/0x240 [nfnetlink_cttimeout]
  age=104 cpu=0 pid=3330
  ___slab_alloc+0x4da/0x540
  __slab_alloc+0x20/0x40
  __kmalloc+0x1c8/0x240
  cttimeout_new_timeout+0xd4/0x240 [nfnetlink_cttimeout]
  nfnetlink_rcv_msg+0x21a/0x230 [nfnetlink]
  [ ... ]

So only when the refcnt decreased to 0, we call kfree_rcu to free the
timeout object. And like nfnetlink_acct do, use atomic_cmpxchg to
avoid race between ctnl_timeout_try_del and ctnl_timeout_put.

Signed-off-by: Liping Zhang <liping.zhang@spreadtrum.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-08-18 15:17:00 +02:00
Liping Zhang
12be15dd5a netfilter: nfnetlink_acct: fix race between nfacct del and xt_nfacct destroy
Suppose that we input the following commands at first:
  # nfacct add test
  # iptables -A INPUT -m nfacct --nfacct-name test

And now "test" acct's refcnt is 2, but later when we try to delete the
"test" nfacct and the related iptables rule at the same time, race maybe
happen:
      CPU0                                    CPU1
  nfnl_acct_try_del                      nfnl_acct_put
  atomic_dec_and_test //ref=1,testfail          -
       -                                 atomic_dec_and_test //ref=0,testok
       -                                 kfree_rcu
  atomic_inc //ref=1                            -

So after the rcu grace period, nf_acct will be freed but it is still linked
in the nfnl_acct_list, and we can access it later, then oops will happen.

Convert atomic_dec_and_test and atomic_inc combinaiton to one atomic
operation atomic_cmpxchg here to fix this problem.

Signed-off-by: Liping Zhang <liping.zhang@spreadtrum.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-08-18 15:16:36 +02:00