If we postpone unhashing of l2tp sessions until the structure is freed, we
risk:

 1. further packets arriving and getting queued while the pseudowire is being
    closed down
 2. the recv path hitting "scheduling while atomic" errors in the case that
    recv drops the last reference to a session and calls l2tp_session_free
    while in atomic context

As such, l2tp sessions should be unhashed from l2tp_core data structures early
in the teardown process prior to calling pseudowire close.  For pseudowires
like l2tp_ppp which have multiple shutdown codepaths, provide an unhash hook.
Signed-off-by: Tom Parkin <tparkin@katalix.com>
Signed-off-by: James Chapman <jchapman@katalix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

l2tp's u64_stats writers were incorrectly synchronised, making it possible to
deadlock a 64bit machine running a 32bit kernel simply by sending the l2tp
code netlink commands while passing data through l2tp sessions.

Previous discussion on netdev determined that alternative solutions such as
spinlock writer synchronisation or per-cpu data would bring unjustified
overhead, given that most users interested in high volume traffic will likely
be running 64bit kernels on 64bit hardware.

As such, this patch replaces l2tp's use of u64_stats with atomic_long_t,
thereby avoiding the deadlock.

Ref:
http://marc.info/?l=linux-netdev&m=134029167910731&w=2
http://marc.info/?l=linux-netdev&m=134079868111131&w=2Signed-off-by: Tom Parkin <tparkin@katalix.com>
Signed-off-by: James Chapman <jchapman@katalix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

If userspace deletes a ppp pseudowire using the netlink API, either by
directly deleting the session or by deleting the tunnel that contains the
session, we need to tear down the corresponding pppox channel.

Rather than trying to manage two pppox unbind codepaths, switch the netlink
and l2tp_core session_close handlers to close via. the l2tp_ppp socket
.release handler.
Signed-off-by: Tom Parkin <tparkin@katalix.com>
Signed-off-by: James Chapman <jchapman@katalix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Add calls to l2tp_session_queue_purge as a part of l2tp_tunnel_closeall
and l2tp_session_delete.  Pseudowire implementations which are deleted only
via. l2tp_core l2tp_session_delete calls can dispense with their own code for
flushing the reorder queue.
Signed-off-by: Tom Parkin <tparkin@katalix.com>
Signed-off-by: James Chapman <jchapman@katalix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

If an l2tp session is deleted, it is necessary to delete skbs in-flight
on the session's reorder queue before taking it down.

Rather than having each pseudowire implementation reaching into the
l2tp_session struct to handle this itself, provide a function in l2tp_core to
purge the session queue.
Signed-off-by: Tom Parkin <tparkin@katalix.com>
Signed-off-by: James Chapman <jchapman@katalix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

It is valid for an existing struct sock object to have a NULL sk_socket
pointer, so don't BUG_ON in l2tp_tunnel_del_work if that should occur.
Signed-off-by: Tom Parkin <tparkin@katalix.com>
Signed-off-by: James Chapman <jchapman@katalix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

When looking up the tunnel socket in struct l2tp_tunnel, hold a reference
whether the socket was created by the kernel or by userspace.
Signed-off-by: Tom Parkin <tparkin@katalix.com>
Signed-off-by: James Chapman <jchapman@katalix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

When a user deletes a tunnel using netlink, all the sessions in the tunnel
should also be deleted.  Since running sessions will pin the tunnel socket
with the references they hold, have the l2tp_tunnel_delete close all sessions
in a tunnel before finally closing the tunnel socket.
Signed-off-by: Tom Parkin <tparkin@katalix.com>
Signed-off-by: James Chapman <jchapman@katalix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

l2tp_core hooks UDP's .destroy handler to gain advance warning of a tunnel
socket being closed from userspace.  We need to do the same thing for
IP-encapsulation sockets.
Signed-off-by: Tom Parkin <tparkin@katalix.com>
Signed-off-by: James Chapman <jchapman@katalix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

l2tp_core internally uses l2tp_tunnel_closeall to close all sessions in a
tunnel when a UDP-encapsulation socket is destroyed.  We need to do something
similar for IP-encapsulation sockets.

Export l2tp_tunnel_closeall as a GPL symbol to enable l2tp_ip and l2tp_ip6 to
call it from their .destroy handlers.
Signed-off-by: Tom Parkin <tparkin@katalix.com>
Signed-off-by: James Chapman <jchapman@katalix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

L2TP sessions hold a reference to the tunnel socket to prevent it going away
while sessions are still active.  However, since tunnel destruction is handled
by the sock sk_destruct callback there is a catch-22: a tunnel with sessions
cannot be deleted since each session holds a reference to the tunnel socket.
If userspace closes a managed tunnel socket, or dies, the tunnel will persist
and it will be neccessary to individually delete the sessions using netlink
commands.  This is ugly.

To prevent this occuring, this patch leverages the udp encapsulation socket
destroy callback to gain early notification when the tunnel socket is closed.
This allows us to safely close the sessions running in the tunnel, dropping
the tunnel socket references in the process.  The tunnel socket is then
destroyed as normal, and the tunnel resources deallocated in sk_destruct.

While we're at it, ensure that l2tp_tunnel_closeall correctly drops session
references to allow the sessions to be deleted rather than leaking.
Signed-off-by: Tom Parkin <tparkin@katalix.com>
Signed-off-by: James Chapman <jchapman@katalix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Users of udp encapsulation currently have an encap_rcv callback which they can
use to hook into the udp receive path.

In situations where a encapsulation user allocates resources associated with a
udp encap socket, it may be convenient to be able to also hook the proto
.destroy operation.  For example, if an encap user holds a reference to the
udp socket, the destroy hook might be used to relinquish this reference.

This patch adds a socket destroy hook into udp, which is set and enabled
in the same way as the existing encap_rcv hook.
Signed-off-by: Tom Parkin <tparkin@katalix.com>
Signed-off-by: James Chapman <jchapman@katalix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Trigger BUG_ON if a group name is longer than GENL_NAMSIZ.
Signed-off-by: Masatake YAMATO <yamato@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Pablo Neira Ayuso says:

====================
The following patchset contains 7 Netfilter/IPVS fixes for 3.9-rc, they are:

* Restrict IPv6 stateless NPT targets to the mangle table. Many users are
  complaining that this target does not work in the nat table, which is the
  wrong table for it, from Florian Westphal.

* Fix possible use before initialization in the netns init path of several
  conntrack protocol trackers (introduced recently while improving conntrack
  netns support), from Gao Feng.

* Fix incorrect initialization of copy_range in nfnetlink_queue, spotted
  by Eric Dumazet during the NFWS2013, patch from myself.

* Fix wrong calculation of next SCTP chunk in IPVS, from Julian Anastasov.

* Remove rcu_read_lock section in IPVS while calling ipv4_update_pmtu
  not required anymore after change introduced in 3.7, again from Julian.

* Fix SYN looping in IPVS state sync if the backup is used a real server
  in DR/TUN modes, this required a new /proc entry to disable the director
  function when acting as backup, also from Julian.

* Remove leftover IP_NF_QUEUE Kconfig after ip_queue removal, noted by
  Paul Bolle.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Kconfig symbol IP_NF_QUEUE is unused since commit
d16cf20e ("netfilter: remove ip_queue
support"). Let's remove it too.
Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

Pull XFS fixes from Ben Myers:

 - Fix for a potential infinite loop which was introduced in commit
   4d559a3b ("xfs: limit speculative prealloc near ENOSPC
   thresholds")

 - Fix for the return type of xfs_iomap_eof_prealloc_initial_size from
   commit a1e16c26 ("xfs: limit speculative prealloc size on sparse
   files")

 - Fix for a failed buffer readahead causing subsequent callers to fail
   incorrectly

* tag 'for-linus-v3.9-rc4' of git://oss.sgi.com/xfs/xfs:
  xfs: ensure we capture IO errors correctly
  xfs: fix xfs_iomap_eof_prealloc_initial_size type
  xfs: fix potential infinite loop in xfs_iomap_prealloc_size()

Mantas Mikulėnas reported that his graphics hardware failed to
initialise after commit f9a37be0 ("x86: Use PCI setup data").

The aim of this commit was to ensure that ROM images were available on
some Apple systems that don't expose the GPU ROM via any other source.
In this case, UEFI appears to have provided a broken ROM image that we
were using even though there was a perfectly valid ROM available via
other sources.  The simplest way to handle this seems to be to just
re-order pci_map_rom() and leave any firmare-supplied ROM to last.
Signed-off-by: Matthew Garrett <matthew.garrett@nebula.com>
Tested-by: Mantas Mikulėnas <grawity@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull sparc fixes from David Miller:
 "Just some minor fixups, a sunsu console setup panic cure, and
  recognition of a Fujitsu sun4v cpu."

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc:
  sparc: remove unused "config BITS"
  sparc: delete "if !ULTRA_HAS_POPULATION_COUNT"
  sparc64: correctly recognize SPARC64-X chips
  sparc,leon: fix GRPCI2 device0 PCI config space access
  sunsu: Fix panic in case of nonexistent port at "console=ttySY" cmdline option

Pull arm64 fixes from Catalin Marinas:

 - Fix !SMP build error.

 - Fix padding computation in struct ucontext (no ABI change).

 - Minor clean-up after the signal patches (unused var).

 - Two old Kconfig options clean-up.

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/cmarinas/linux-aarch64:
  arm64: Kconfig.debug: Remove unused CONFIG_DEBUG_ERRORS
  arm64: Do not select GENERIC_HARDIRQS_NO_DEPRECATED
  arm64: fix padding computation in struct ucontext
  arm64: Fix build error with !SMP
  arm64: Removed unused variable in compat_setup_rt_frame()

sparc's asm/module.h got removed in commit
786d35d4 ("Make most arch asm/module.h
files use asm-generic/module.h"). That removed the only two uses of this
Kconfig symbol. So we can remove its entry too.

> >From arch/sparc/Makefile:
>     ifeq ($(CONFIG_SPARC32),y)
>     [...]
>
>     [...]
>     export BITS    := 32
>     [...]
>
>     else
>     [...]
>
>     [...]
>     export BITS   := 64
>     [...]
>
> So $(BITS) is set depending on whether CONFIG_SPARC32 is set or not.
> Using $(BITS) in sparc's Makefiles is not using CONFIG_BITS. That
> doesn't count as usage of "config BITS".
Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

Pull networking fixes from David Miller:

 1) Fix ARM BPF JIT handling of negative 'k' values, from Chen Gang.

 2) Insufficient space reserved for bridge netlink values, fix from
    Stephen Hemminger.

 3) Some dst_neigh_lookup*() callers don't interpret error pointer
    correctly, fix from Zhouyi Zhou.

 4) Fix transport match in SCTP active_path loops, from Xugeng Zhang.

 5) Fix qeth driver handling of multi-order SKB frags, from Frank
    Blaschka.

 6) fec driver is missing napi_disable() call, resulting in crashes on
    unload, from Georg Hofmann.

 7) Don't try to handle PMTU events on a listening socket, fix from Eric
    Dumazet.

 8) Fix timestamp location calculations in IP option processing, from
    David Ward.

 9) FIB_TABLE_HASHSZ setting is not controlled by the correct kconfig
    tests, from Denis V Lunev.

10) Fix TX descriptor push handling in SFC driver, from Ben Hutchings.

11) Fix isdn/hisax and tulip/de4x5 kconfig dependencies, from Arnd
    Bergmann.

12) bnx2x statistics don't handle 4GB rollover correctly, fix from
    Maciej Żenczykowski.

13) Openvswitch bug fixes for vport del/new error reporting, missing
    genlmsg_end() call in netlink processing, and mis-parsing of
    LLC/SNAP ethernet types.  From Rich Lane.

14) SKB pfmemalloc state should only be propagated from the head page of
    a compound page, fix from Pavel Emelyanov.

15) Fix link handling in tg3 driver for 5715 chips when autonegotation
    is disabled.  From Nithin Sujir.

16) Fix inverted test of cpdma_check_free_tx_desc return value in
    davinci_emac driver, from Mugunthan V N.

17) vlan_depth is incorrectly calculated in skb_network_protocol(), from
    Li RongQing.

18) Fix probing of Gobi 1K devices in qmi_wwan driver, and fix NCM
    device mode backwards compat in cdc_ncm driver.  From Bjørn Mork.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (52 commits)
  inet: limit length of fragment queue hash table bucket lists
  qeth: Fix scatter-gather regression
  qeth: Fix invalid router settings handling
  qeth: delay feature trace
  tcp: dont handle MTU reduction on LISTEN socket
  bnx2x: fix occasional statistics off-by-4GB error
  vhost/net: fix heads usage of ubuf_info
  bridge: Add support for setting BR_ROOT_BLOCK flag.
  bnx2x: add missing napi deletion in error path
  drivers: net: ethernet: ti: davinci_emac: fix usage of cpdma_check_free_tx_desc()
  ethernet/tulip: DE4x5 needs VIRT_TO_BUS
  isdn: hisax: netjet requires VIRT_TO_BUS
  net: cdc_ncm, cdc_mbim: allow user to prefer NCM for backwards compatibility
  rtnetlink: Mask the rta_type when range checking
  Revert "ip_gre: make ipgre_tunnel_xmit() not parse network header as IP unconditionally"
  Fix dst_neigh_lookup/dst_neigh_lookup_skb return value handling bug
  smsc75xx: configuration help incorrectly mentions smsc95xx
  net: fec: fix missing napi_disable call
  net: fec: restart the FEC when PHY speed changes
  skb: Propagate pfmemalloc on skb from head page only
  ...

Commit 2d78d4be ("[PATCH] bitops:
sparc64: use generic bitops") made the default of GENERIC_HWEIGHT depend
on !ULTRA_HAS_POPULATION_COUNT. But since there's no Kconfig symbol with
that name, this always evaluates to true. Delete this dependency.
Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

The Kconfig entry for DEBUG_ERRORS is a verbatim copy of the former arm
entry for that symbol. It got removed in v2.6.39 because it wasn't
actually used anywhere. There are still no users of DEBUG_ERRORS so
remove this entry too.
Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
[catalin.marinas@arm.com: removed option from defconfig]
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

Config option GENERIC_HARDIRQS_NO_DEPRECATED was removed in commit
78c89825 ("genirq: Remove the now obsolete
config options and select statements"), but the select was accidentally
reintroduced in commit 8c2c3df3 ("arm64:
Build infrastructure").
Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

This patch introduces a constant limit of the fragment queue hash
table bucket list lengths. Currently the limit 128 is choosen somewhat
arbitrary and just ensures that we can fill up the fragment cache with
empty packets up to the default ip_frag_high_thresh limits. It should
just protect from list iteration eating considerable amounts of cpu.

If we reach the maximum length in one hash bucket a warning is printed.
This is implemented on the caller side of inet_frag_find to distinguish
between the different users of inet_fragment.c.

I dropped the out of memory warning in the ipv4 fragment lookup path,
because we already get a warning by the slab allocator.

Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Jesper Dangaard Brouer <jbrouer@redhat.com>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

This patch fixes a scatter-gather regression introduced with

commit 5640f768 net: use a per task frag allocator

Now the qeth driver can cope with bigger framents and split a fragment in
sub framents if required.
Signed-off-by: Frank Blaschka <blaschka@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Give a bad return code when specifying a router setting that is either
invalid or not support on the respective device type. In addition, fall back
the previous setting instead of silently switching back to 'no routing'.
Signed-off-by: Stefan Raspl <raspl@linux.vnet.ibm.com>
Signed-off-by: Frank Blaschka <blaschka@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Delay tracing of the card features until the optional commands have been
enabled.
Signed-off-by: Stefan Raspl <raspl@linux.vnet.ibm.com>
Signed-off-by: Frank Blaschka <blaschka@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

In 3.7 we added code that uses ipv4_update_pmtu but after commit
c5ae7d41 (ipv4: must use rcu protection while calling fib_lookup)
the RCU lock is not needed.
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>

Dmitry Akindinov is reporting for a problem where SYNs are looping
between the master and backup server when the backup server is used as
real server in DR mode and has IPVS rules to function as director.

Even when the backup function is enabled we continue to forward
traffic and schedule new connections when the current master is using
the backup server as real server. While this is not a problem for NAT,
for DR and TUN method the backup server can not determine if a request
comes from client or from director.

To avoid such loops add new sysctl flag backup_only. It can be needed
for DR/TUN setups that do not need backup and director function at the
same time. When the backup function is enabled we stop any forwarding
and pass the traffic to the local stack (real server mode). The flag
disables the director function when the backup function is enabled.

For setups that enable backup function for some virtual services and
director function for other virtual services there should be another
more complex solution to support DR/TUN mode, may be to assign
per-virtual service syncid value, so that we can differentiate the
requests.
Reported-by: Dmitry Akindinov <dimak@stalker.com>
Tested-by: German Myzovsky <lawyer@sipnet.ru>
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>

Pull hwmon fixes from Jean Delvare.

* 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/staging:
  hwmon: (lm75) Fix tcn75 prefix
  hwmon: (lm75.h) Update header inclusion
  MAINTAINERS: Remove Mark M. Hoffman

Somehow the driver snuck in with these still in it.
Signed-off-by: Ben Collins <ben.c@servergy.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull workqueue fix from Tejun Heo:
 "Lai's patch to fix highly unlikely but still possible workqueue stall
  during CPU hotunplug."

* 'for-3.9-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
  workqueue: fix possible pool stall bug in wq_unbind_fn()

Fix wrong but non-fatal access to chunk length.
sch->length should be in network order, next chunk should
be aligned to 4 bytes. Problem noticed in sparse output.
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>

The TCN75 has its own prefix for a long time now.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>

File lm75.h used to include <linux/hwmon.h> for SENSORS_LIMIT() but
this function is gone by now. Instead we call clamp_val() so we should
include <linux/kernel.h>, where this function is declared.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>

Mark M. Hoffman stopped working on the Linux kernel several years
ago, so he should no longer be listed as a driver maintainer. I'm not
even sure if his e-mail address still works.

I can take over 3 drivers he was responsible for, the 4th one will
fall down to the subsystem maintainer.

Also give Mark credit for all the good work he did.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: "Mark M. Hoffman" <mhoffman@lightlink.com>
Acked-by: Guenter Roeck <linux@roeck-us.net>
Cc: Wolfram Sang <wolfram@the-dreams.de>

Failed buffer readahead can leave the buffer in the cache marked
with an error. Most callers that then issue a subsequent read on the
buffer do not zero the b_error field out, and so we may incorectly
detect an error during IO completion due to the stale error value
left on the buffer.

Avoid this problem by zeroing the error before IO submission. This
ensures that the only IO errors that are detected those captured
from are those captured from bio submission or completion.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>

(cherry picked from commit c163f9a1)

Fix the return type of xfs_iomap_eof_prealloc_initial_size() to
xfs_fsblock_t to reflect the fact that the return value may be an
unsigned 64 bits if XFS_BIG_BLKNOS is defined.
Signed-off-by: Mark Tinguely <tinguely@sgi.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Ben Myers <bpm@sgi.com>

(cherry picked from commit e8108ced)

If freesp == 0, we could end up in an infinite loop while squashing
the preallocation. Break the loop when we've killed the prealloc
entirely.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Ben Myers <bpm@sgi.com>

(cherry picked from commit e78c420b)