Until recently, mac80211 overwrote all the statistics it could
provide when getting called, but it now relies on the struct
having been zeroed by the caller. This was always the case in
nl80211, but wext used a static struct which could even cause
values from one device leak to another.

Using a static struct is OK (as even documented in a comment)
since the whole usage of this function and its return value is
always locked under RTNL. Not clearing the struct for calling
the driver has always been wrong though, since drivers were
free to only fill values they could report, so calling this
for one device and then for another would always have leaked
values from one to the other.

Fix this by initializing the structure in question before the
driver method call.

This fixes https://bugzilla.kernel.org/show_bug.cgi?id=99691

Cc: stable@vger.kernel.org
Reported-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Reported-by: Alexander Kaltsas <alexkaltsas@gmail.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Pull networking fixes from David Miller:

 1) Fix stack allocation in s390 BPF JIT, from Michael Holzheu.

 2) Disable LRO on openvswitch paths, from Jiri Benc.

 3) UDP early demux doesn't handle multicast group membership properly,
    fix from Shawn Bohrer.

 4) Fix TX queue hang due to incorrect handling of mixed sized fragments
    and linearlization in i40e driver, from Anjali Singhai Jain.

 5) Cannot use disable_irq() in timer handler of AMD xgbe driver, from
    Thomas Lendacky.

 6) b2net driver improperly assumes pci_alloc_consistent() gives zero'd
    out memory, use dma_zalloc_coherent().  From Sriharsha Basavapatna.

 7) Fix use-after-free in MPLS and ipv6, from Robert Shearman.

 8) Missing neif_napi_del() calls in cleanup paths of b44 driver, from
    Hauke Mehrtens.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net:
  net: replace last open coded skb_orphan_frags with function call
  net: bcmgenet: power on MII block for all MII modes
  ipv6: Fix protocol resubmission
  ipv6: fix possible use after free of dev stats
  b44: call netif_napi_del()
  bridge: disable softirqs around br_fdb_update to avoid lockup
  Revert "bridge: use _bh spinlock variant for br_fdb_update to avoid lockup"
  mpls: fix possible use after free of device
  be2net: Replace dma/pci_alloc_coherent() calls with dma_zalloc_coherent()
  bridge: use _bh spinlock variant for br_fdb_update to avoid lockup
  amd-xgbe: Use disable_irq_nosync from within timer function
  rhashtable: add missing import <linux/export.h>
  i40e: Make sure to be in VEB mode if SRIOV is enabled at probe
  i40e: start up in VEPA mode by default
  i40e/i40evf: Fix mixed size frags and linearization
  ipv4/udp: Verify multicast group is ours in upd_v4_early_demux()
  openvswitch: disable LRO
  s390/bpf: fix bpf frame pointer setup
  s390/bpf: fix stack allocation

Pull last-minute virtio fix from Michael Tsirkin:
 "This fixes a minor issue affecting multiqueue virtio net when user
  keeps changing the number of active queues and CPUs are added and
  removed by hotplug"

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
  virtio_pci: Clear stale cpumask when setting irq affinity

Pull ARM SoC fixes from Kevin Hilman:
 "About 10 days worth of small bug fixes, and the (hopefully) final
  round fixes for from arm-soc land for the -rc cycle.  Nothing special
  to note, but here's a brief summary of fixes by SoC type:

   - OMAP:
        small set of misc DT fixes; boot fix for THUMB2 kernel

   - mediatek:
        PMIC fixes; DT fix for model name

   - exynos:
        wakeup interupt fixes for 3250

   - mvebu:
        revert mbus patch which broke DMA masters

* tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc:
  ARM: dts: am335x-boneblack: disable RTC-only sleep to avoid hardware damage
  ARM: dts: AM35xx: fix system control module clocks
  arm64: dts: mt8173-evb: fix model name
  ARM: exynos: Fix wake-up interrupts for Exynos3250
  ARM: dts: Fix n900 dts file to work around 4.1 touchscreen regression on n900
  ARM: dts: Fix dm816x to use right compatible flag for MUSB
  ARM: OMAP3: Fix booting with thumb2 kernel
  Revert "bus: mvebu-mbus: make sure SDRAM CS for DMA don't overlap the MBus bridge window"
  bus: mvebu-mbus: do not set WIN_CTRL_SYNCBARRIER on non io-coherent platforms.
  ARM: mvebu: armada-xp-linksys-mamba: Disable internal RTC
  soc: mediatek: Add compile dependency to pmic-wrapper
  soc: mediatek: PMIC wrap: Fix register state machine handling
  soc: mediatek: PMIC wrap: Fix clock rate handling

Commit 70008aa5 ("skbuff: convert to skb_orphan_frags") replaced
open coded tests of SKBTX_DEV_ZEROCOPY and skb_copy_ubufs with calls
to helper function skb_orphan_frags. Apply that to the last remaining
open coded site.
Signed-off-by: Willem de Bruijn <willemb@google.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The RGMII block is currently only powered on when using RGMII or
RGMII_NO_ID, which is not correct when using the GENET interface in MII
or Reverse MII modes. We always need to power on the RGMII interface for
this block to properly work, regardless of the MII mode in which we
operate.

Fixes: aa09677c ("net: bcmgenet: add MDIO routines")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

UDP encapsulation is broken on IPv6. This is because the logic to resubmit
the nexthdr is inverted, checking for a ret value > 0 instead of < 0. Also,
the resubmit label is in the wrong position since we already get the
nexthdr value when performing decapsulation. In addition the skb pull is no
longer necessary either.

This changes the return value check to look for < 0, using it for the
nexthdr on the next iteration, and moves the resubmit label to the proper
location.

With these changes the v6 code now matches what we do in the v4 ip input
code wrt resubmitting when decapsulating.
Signed-off-by: Josh Hunt <johunt@akamai.com>
Acked-by: "Tom Herbert" <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The memory pointed to by idev->stats.icmpv6msgdev,
idev->stats.icmpv6dev and idev->stats.ipv6 can each be used in an RCU
read context without taking a reference on idev. For example, through
IP6_*_STATS_* calls in ip6_rcv. These memory blocks are freed without
waiting for an RCU grace period to elapse. This could lead to the
memory being written to after it has been freed.

Fix this by using call_rcu to free the memory used for stats, as well
as idev after an RCU grace period has elapsed.
Signed-off-by: Robert Shearman <rshearma@brocade.com>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

Merge tag 'omap-for-v4.1/fixes-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap into fixes

Merge omap fixes for v4.1, urgent fix to avoid potential hardware damage From Tony Lindgren:

Omap fixes for the -rc cycle, including a fix for potential hardware
breakage on BeagleBones:

- BeagleBones don't support RTC-only mode, it can cause hardware
  damage if system-power-controller is specified without
  ti,pmic-shutdown-controller

- Fix a recent regression to am3517 SoCs caused by the recent clock
  move that was not noticed until now despite automated boot
  testing

- Fix a regression for n900 touchscreen triggered by recent
  recent input changes

- Fix compatible property for dm816x USB to avoid errors with
  USB Ethernet

- Fix oops for omap3 when built with CONFIG_THUMB2_KERNEL

* tag 'omap-for-v4.1/fixes-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap:
  ARM: dts: am335x-boneblack: disable RTC-only sleep to avoid hardware damage
  ARM: dts: AM35xx: fix system control module clocks
  ARM: dts: Fix n900 dts file to work around 4.1 touchscreen regression on n900
  ARM: dts: Fix dm816x to use right compatible flag for MUSB
  ARM: OMAP3: Fix booting with thumb2 kernel

Pull Intel IOMMU fix from David Woodhouse:
 "This fixes an oops when attempting to enable 1:1 passthrough mode for
  devices on which VT-d translation was disabled anyway.

  It's actually a long-standing bug but recent changes (commit
  18436afd: "iommu/vt-d: Allow RMRR on graphics devices too") have
  made it much easier to trigger with 'iommu=pt intel_iommu=igfx_off' on
  the command line"

* git://git.infradead.org/intel-iommu:
  iommu/vt-d: Fix passthrough mode with translation-disabled devices

Pull libata fixes from Tejun Heo:
 "Two driver fixes.  One is for an ahci_mvebu controller config bug and
  the other fixes pata_octeon_cf build issue"

* 'for-4.1-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/libata:
  pata_octeon_cf: fix broken build
  ata: ahci_mvebu: Fix wrongly set base address for the MBus window setting

MODULE_DEVICE_TABLE is referring to wrong driver's table and breaks the
build. Fix that.

Cc: stable@vger.kernel.org
Signed-off-by: Aaro Koskinen <aaro.koskinen@nokia.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

When the driver gets unregistered a call to netif_napi_del() was
missing, this all was also missing in the error paths of
b44_init_one().
Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

br_fdb_update() can be called in process context in the following way:
br_fdb_add() -> __br_fdb_add() -> br_fdb_update() (if NTF_USE flag is set)
so we need to disable softirqs because there are softirq users of the
hash_lock. One easy way to reproduce this is to modify the bridge utility
to set NTF_USE, enable stp and then set maxageing to a low value so
br_fdb_cleanup() is called frequently and then just add new entries in
a loop. This happens because br_fdb_cleanup() is called from timer/softirq
context. The spin locks in br_fdb_update were _bh before commit f8ae737d
("[BRIDGE]: forwarding remove unneeded preempt and bh diasables")
and at the time that commit was correct because br_fdb_update() couldn't be
called from process context, but that changed after commit:
292d1398 ("bridge: add NTF_USE support")
Using local_bh_disable/enable around br_fdb_update() allows us to keep
using the spin_lock/unlock in br_fdb_update for the fast-path.
Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Fixes: 292d1398 ("bridge: add NTF_USE support")
Signed-off-by: David S. Miller <davem@davemloft.net>

This reverts commit 1d7c4903.

Nikolay Aleksandrov has a better version of this fix.
Signed-off-by: David S. Miller <davem@davemloft.net>

The mpls device is used in an RCU read context without a lock being
held. As the memory is freed without waiting for the RCU grace period
to elapse, the freed memory could still be in use.

Address this by using kfree_rcu to free the memory for the mpls device
after the RCU grace period has elapsed.

Fixes: 03c57747 ("mpls: Per-device MPLS state")
Signed-off-by: Robert Shearman <rshearma@brocade.com>
Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Pull MIPS updates from Ralf Baechle:
 "Eight fixes across arch/mips.  Nothing stands particuarly out nor is
  complicated but fixes keep coming in at a higher than comfortable
  rate"

* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus:
  MIPS: KVM: Do not sign extend on unsigned MMIO load
  MIPS: BPF: Fix stack pointer allocation
  MIPS: Loongson-3: Fix a cpu-hotplug issue in loongson3_ipi_interrupt()
  MIPS: Fix enabling of DEBUG_STACKOVERFLOW
  MIPS: c-r4k: Fix typo in probe_scache()
  MIPS: Avoid an FPE exception in FCSR mask probing
  MIPS: ath79: Add a missing new line in log message
  MIPS: ralink: Fix clearing the illegal access interrupt

There are several places in the driver (all in control paths) where
coherent dma memory is being allocated using either dma_alloc_coherent()
or the deprecated pci_alloc_consistent(). All these calls should be
changed to use dma_zalloc_coherent() to avoid uninitialized fields in
data structures backed by this memory.
Reported-by: Joerg Roedel <jroedel@suse.de>
Tested-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Sriharsha Basavapatna <sriharsha.basavapatna@avagotech.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

br_fdb_update() can be called in process context in the following way:
br_fdb_add() -> __br_fdb_add() -> br_fdb_update() (if NTF_USE flag is set)
so we need to use spin_lock_bh because there are softirq users of the
hash_lock. One easy way to reproduce this is to modify the bridge utility
to set NTF_USE, enable stp and then set maxageing to a low value so
br_fdb_cleanup() is called frequently and then just add new entries in
a loop. This happens because br_fdb_cleanup() is called from timer/softirq
context. These locks were _bh before commit f8ae737d
("[BRIDGE]: forwarding remove unneeded preempt and bh diasables")
and at the time that commit was correct because br_fdb_update() couldn't be
called from process context, but that changed after commit:
292d1398 ("bridge: add NTF_USE support")
Signed-off-by: Wilson Kok <wkok@cumulusnetworks.com>
Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Fixes: 292d1398 ("bridge: add NTF_USE support")
Signed-off-by: David S. Miller <davem@davemloft.net>

Since the Tx timer function runs in softirq context the driver needs
to call disable_irq_nosync instead of a disable_irq.
Reported-by: Josh Stone <jistone@redhat.com>
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

rhashtable uses EXPORT_SYMBOL_GPL() without importing linux/export.h
directly it is only imported indirectly through some other includes.
Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

Pull driver core fixes from Greg KH:
 "Here are two fixes for the driver core that resolve some reported
  issues.

  One is a regression from 4.0, the other a fixes a reported oops that
  has been there since 3.19.

  Both have been in linux-next for a while with no problems"

* tag 'driver-core-4.1-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
  drivers/base: cacheinfo: handle absence of caches
  drivers: of/base: move of_init to driver_init

Pull staging / IIO fixes from Greg KH:
 "Here are some IIO driver fixes to resolve reported issues, some ozwpan
  fixes for some reported CVE problems, and a rtl8712 driver fix for a
  reported regression.

  All have been in linux-next successfully"

* tag 'staging-4.1-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging:
  staging: rtl8712: fix stack dump
  ozwpan: unchecked signed subtraction leads to DoS
  ozwpan: divide-by-zero leading to panic
  ozwpan: Use unsigned ints to prevent heap overflow
  ozwpan: Use proper check to prevent heap overflow
  iio: adc: twl6030-gpadc: Fix modalias
  iio: adis16400: Fix burst transfer for adis16448
  iio: adis16400: Fix burst mode
  iio: adis16400: Compute the scan mask from channel indices
  iio: adis16400: Use != channel indices for the two voltage channels
  iio: adis16400: Report pressure channel scale

Pull tty/serial driver fixes from Greg KH:
 "Here are a few TTY and Serial driver fixes for reported regressions
  and crashes.

  All of these have been in linux-next with no reported problems"

* tag 'tty-4.1-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
  n_tty: Fix auditing support for cannonical mode
  serial: 8250_omap: provide complete custom startup & shutdown callbacks
  n_tty: Fix calculation of size in canon_copy_from_read_buf
  serial: imx: Fix DMA handling for IDLE condition aborts
  serial/amba-pl011: Unconditionally poll for FIFO space before each TX char

Pull USB and PHY driver fixes from Greg KH:
 "Here are some USB and PHY driver fixes that resolve some reported
  regressions.  Also in here are some new device ids.

  All of the details are in the shortlog and these patches have been in
  linux-next with no problems"

* tag 'usb-4.1-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (22 commits)
  USB: cp210x: add ID for HubZ dual ZigBee and Z-Wave dongle
  usb: renesas_usbhs: Don't disable the pipe if Control write status stage
  usb: renesas_usbhs: Fix fifo unclear in usbhsf_prepare_pop
  usb: gadget: f_fs: fix check in read operation
  usb: musb: fix order of conditions for assigning end point operations
  usb: gadget: f_uac1: check return code from config_ep_by_speed
  usb: gadget: ffs: fix: Always call ffs_closed() in ffs_data_clear()
  usb: gadget: g_ffs: Fix counting of missing_functions
  usb: s3c2410_udc: correct reversed pullup logic
  usb: dwc3: gadget: Fix incorrect DEPCMD and DGCMD status macros
  usb: phy: tahvo: Pass the IRQF_ONESHOT flag
  usb: phy: ab8500-usb: Pass the IRQF_ONESHOT flag
  usb: renesas_usbhs: Revise the binding document about the dma-names
  usb: host: xhci: add mutex for non-thread-safe data
  usb: make module xhci_hcd removable
  USB: serial: ftdi_sio: Add support for a Motion Tracker Development Board
  usb: gadget: f_midi: fix segfault when reading empty id
  phy: phy-rcar-gen2: Fix USBHS_UGSTS_LOCK value
  phy: omap-usb2: invoke pm_runtime_disable on error path
  phy: fix Kconfig dependencies
  ...

Pull devicetree fix from Grant Likely:
 "Stupid typo fix for v4.1.  One of the IS_ENABLED() macro calls forgot
  the CONFIG_ prefix.  Only affects a tiny number of platforms, but
  still..."

* tag 'devicetree-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/glikely/linux:
  of/dynamic: Fix test for PPC_PSERIES

Pull drm fixes from Dave Airlie:
 "i915 has a bunch of fixes, and Russell found a bug in sysfs writing
  handling that results in userspace getting stuck"

* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux:
  drm: fix writing to /sys/class/drm/*/status
  drm/i915: Move WaBarrierPerformanceFixDisable:skl to skl code from chv code
  drm/i915: Include G4X/VLV/CHV in self refresh status
  drm/i915: Initialize HWS page address after GPU reset
  drm/i915: Don't skip request retirement if the active list is empty
  drm/i915/hsw: Fix workaround for server AUX channel clock divisor

Pull input subsystem fixes from Dmitry Torokhov:
 "Just a couple touchpad drivers fixups"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
  Input: alps - do not reduce trackpoint speed by half
  Input: elantech - add new icbody type
  Input: elantech - fix detection of touchpads where the revision matches a known rate

Pull swiotlb fix from Konrad Rzeszutek Wilk:
 "Tiny little fix which just converts an function to be static.  Really
  tiny"

* 'stable/for-linus-4.1' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/swiotlb:
  swiotlb: do not export map_single function

Pull iBFT fix from Konrad Rzeszutek Wilk:
 "One single fix from Chris to workaround UEFI platforms failing with
  iSCSI IBFT"

* 'stable/for-linus-4.1' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/ibft:
  iscsi_ibft: filter null v4-mapped v6 addresses

Fix possible unintended sign extension in unsigned MMIO loads by casting
to uint16_t in the case of mmio_needed != 2.
Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org>
Reviewed-by: James Hogan <james.hogan@imgtec.com>
Tested-by: James Hogan <james.hogan@imgtec.com>
Cc: Gleb Natapov <gleb@kernel.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: kvm@vger.kernel.org
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/9985/Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

Fix stack pointer offset which could potentially corrupt
argument registers in the previous frame. The calculated offset
reflects the size of all the registers we need to preserve so there
is no need for this erroneous subtraction.

[ralf@linux-mips.org: Fixed conflict due to only applying this fix part
of the entire series as part of 4.1 fixes.]
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: netdev@vger.kernel.org
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Daniel Borkmann <dborkman@redhat.com>
Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Cc: linux-kernel@vger.kernel.org
Cc: linux-mips@linux-mips.org
Patchwork: http://patchwork.linux-mips.org/patch/10527/Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

setup_per_cpu_areas() only setup __per_cpu_offset[] for each possible
cpu, but loongson_sysconf.nr_cpus can be greater than possible cpus
(due to reserved_cpus_mask). So in loongson3_ipi_interrupt(), percpu
access will touch the original varible in .data..percpu section which
has been freed. Without this patch, cpu-hotplug will cause memery
corruption.
Signed-off-by: Huacai Chen <chenhc@lemote.com>
Cc: John Crispin <john@phrozen.org>
Cc: Steven J. Hill <Steven.Hill@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: Fuxin Zhang <zhangfx@lemote.com>
Cc: Zhangjin Wu <wuzhangjin@gmail.com>
Patchwork: http://patchwork.linux-mips.org/patch/10524/Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

Commit 334c86c4 ("MIPS: IRQ: Add stackoverflow detection") added
kernel stack overflow detection, however it only enabled it conditional
upon the preprocessor definition DEBUG_STACKOVERFLOW, which is never
actually defined. The Kconfig option is called DEBUG_STACKOVERFLOW,
which manifests to the preprocessor as CONFIG_DEBUG_STACKOVERFLOW, so
switch it to using that definition instead.

Fixes: 334c86c4 ("MIPS: IRQ: Add stackoverflow detection")
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Adam Jiang <jiang.adam@gmail.com>
Cc: linux-mips@linux-mips.org
Cc: <stable@vger.kernel.org> # 2.6.37+
Patchwork: http://patchwork.linux-mips.org/patch/10531/Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

Fixes a typo in arch/mips/mm/c-r4k.c's probe_scache().
Signed-off-by: Joshua Kinard <kumba@gentoo.org>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

Jeff Kirsher says:

====================
Intel Wired LAN Driver Updates 2015-06-04

This series contains updates to i40e and i40evf.

Anjali provides three fixes, first to resolve a Tx queue hang if mixed
size frags are passed to the driver while using TSO.  There was a corner
case where we needed to linearize but we were not.  Next fixes a bug in
the default configuration which prevented a software bridge loaded on the
PF interface from working correctly because broadcast packets are
incorrectly looped back.  Lastly fixes an NPAR bug when SRIOV is enabled,
where we need to be in VEB mode, not VEPA mode at probe.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

I've had reports of UEFI platforms failing iSCSI boot in various
configurations, that ended up being caused by network initialization
scripts getting tripped up by unexpected null addresses (0.0.0.0) being
reported for gateways, dhcp servers, and dns servers.

The tianocore EDK2 iSCSI driver generates an iBFT table that always uses
IPv4-mapped IPv6 addresses for the NIC structure fields.  This results
in values that are "not present or not specified" being reported as
::ffff:0.0.0.0 rather than all zeros as specified.

The iscsi_ibft module filters unspecified fields from the iBFT from
sysfs, preventing userspace from using invalid values and making it easy
to check for the presence of a value.  This currently fails in regard to
these mapped null addresses.

In order to remain consistent with how the iBFT information is exposed,
we should accommodate the behavior of the tianocore iSCSI driver as it's
already in the wild in a large number of servers.

Tested under qemu using an OVMF build of tianocore EDK2.
Signed-off-by: Chris Leech <cleech@redhat.com>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>

The map_single() function is not defined as static, even though it
doesn't seem to be used anywhere else in the kernel. Make it static to
avoid namespace pollution since this is a rather generic symbol.
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>

Writing to a file is supposed to return the number of bytes written.
Returning zero unfortunately causes bash to constantly spin trying
to write to the sysfs file, to such an extent that even ^c and ^z
have no effect.  The only way out of that is to kill the shell and
log back in.  This isn't nice behaviour.

Fix it by returning the number of characters written to sysfs files.

[airlied: used suggestion from Al Viro]
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Dave Airlie <airlied@redhat.com>