SFP modules connected using the SGMII interface have their own PHYs which
are handled by the struct phylink's phydev field. On the other hand, for
the modules connected using 1000Base-X interface that field is not set.

Since commit ce0aa27f ("sfp: add sfp-bus to bridge between network
devices and sfp cages") phylink_start() ends up setting the phydev field
using the sfp-bus infrastructure, which eventually calls phy_start() on it,
and then calling phy_start() again on the same phydev from phylink_start()
itself. Similar call sequence holds for phylink_stop(), only in the reverse
order. This results in WARNs during network interface bringup and shutdown
when a copper SFP module is connected, as phy_start() and phy_stop() are
called twice in a row for the same phy_device:

  % ip link set up dev eth0
  ------------[ cut here ]------------
  called from state UP
  WARNING: CPU: 1 PID: 155 at drivers/net/phy/phy.c:895 phy_start+0x74/0xc0
  Modules linked in:
  CPU: 1 PID: 155 Comm: backend Not tainted 5.2.0+ #1
  NIP:  c0227bf0 LR: c0227bf0 CTR: c004d224
  REGS: df547720 TRAP: 0700   Not tainted  (5.2.0+)
  MSR:  00029000 <CE,EE,ME>  CR: 24002822  XER: 00000000

  GPR00: c0227bf0 df5477d8 df5d7080 00000014 df9d2370 df9d5ac4 1f4eb000 00000001
  GPR08: c061fe58 00000000 00000000 df5477d8 0000003c 100c8768 00000000 00000000
  GPR16: df486a00 c046f1c8 c046eea0 00000000 c046e904 c0239604 db68449c 00000000
  GPR24: e9083204 00000000 00000001 db684460 e9083404 00000000 db6dce00 db6dcc00
  NIP [c0227bf0] phy_start+0x74/0xc0
  LR [c0227bf0] phy_start+0x74/0xc0
  Call Trace:
  [df5477d8] [c0227bf0] phy_start+0x74/0xc0 (unreliable)
  [df5477e8] [c023cad0] startup_gfar+0x398/0x3f4
  [df547828] [c023cf08] gfar_enet_open+0x364/0x374
  [df547898] [c029d870] __dev_open+0xe4/0x140
  [df5478c8] [c029db70] __dev_change_flags+0xf0/0x188
  [df5478f8] [c029dc28] dev_change_flags+0x20/0x54
  [df547918] [c02ae304] do_setlink+0x310/0x818
  [df547a08] [c02b1eb8] __rtnl_newlink+0x384/0x6b0
  [df547c28] [c02b222c] rtnl_newlink+0x48/0x68
  [df547c48] [c02ad7c8] rtnetlink_rcv_msg+0x240/0x27c
  [df547c98] [c02cc068] netlink_rcv_skb+0x8c/0xf0
  [df547cd8] [c02cba3c] netlink_unicast+0x114/0x19c
  [df547d08] [c02cbd74] netlink_sendmsg+0x2b0/0x2c0
  [df547d58] [c027b668] sock_sendmsg_nosec+0x20/0x40
  [df547d68] [c027d080] ___sys_sendmsg+0x17c/0x1dc
  [df547e98] [c027df7c] __sys_sendmsg+0x68/0x84
  [df547ef8] [c027e430] sys_socketcall+0x1a0/0x204
  [df547f38] [c000d1d8] ret_from_syscall+0x0/0x38
  --- interrupt: c01 at 0xfd4e030
      LR = 0xfd4e010
  Instruction dump:
  813f0188 38800000 2b890005 419d0014 3d40c046 5529103a 394aa208 7c8a482e
  3c60c046 3863a1b8 4cc63182 4be009a1 <0fe00000> 48000030 3c60c046 3863a1d0
  ---[ end trace d4c095aeaf6ea998 ]---

and

  % ip link set down dev eth0
  ------------[ cut here ]------------
  called from state HALTED
  WARNING: CPU: 1 PID: 184 at drivers/net/phy/phy.c:858 phy_stop+0x3c/0x88

  <...>

  Call Trace:
  [df581788] [c0228450] phy_stop+0x3c/0x88 (unreliable)
  [df581798] [c022d548] sfp_sm_phy_detach+0x1c/0x44
  [df5817a8] [c022e8cc] sfp_sm_event+0x4b0/0x87c
  [df581848] [c022f04c] sfp_upstream_stop+0x34/0x44
  [df581858] [c0225608] phylink_stop+0x7c/0xe4
  [df581868] [c023c57c] stop_gfar+0x7c/0x94
  [df581888] [c023c5b8] gfar_close+0x24/0x94
  [df5818a8] [c0298688] __dev_close_many+0xdc/0xf8
  [df5818c8] [c029db58] __dev_change_flags+0xd8/0x188
  [df5818f8] [c029dc28] dev_change_flags+0x20/0x54
  [df581918] [c02ae304] do_setlink+0x310/0x818
  [df581a08] [c02b1eb8] __rtnl_newlink+0x384/0x6b0
  [df581c28] [c02b222c] rtnl_newlink+0x48/0x68
  [df581c48] [c02ad7c8] rtnetlink_rcv_msg+0x240/0x27c
  [df581c98] [c02cc068] netlink_rcv_skb+0x8c/0xf0
  [df581cd8] [c02cba3c] netlink_unicast+0x114/0x19c
  [df581d08] [c02cbd74] netlink_sendmsg+0x2b0/0x2c0
  [df581d58] [c027b668] sock_sendmsg_nosec+0x20/0x40
  [df581d68] [c027d080] ___sys_sendmsg+0x17c/0x1dc
  [df581e98] [c027df7c] __sys_sendmsg+0x68/0x84
  [df581ef8] [c027e430] sys_socketcall+0x1a0/0x204
  [df581f38] [c000d1d8] ret_from_syscall+0x0/0x38

  <...>

  ---[ end trace d4c095aeaf6ea999 ]---

SFP modules with the 1000Base-X interface are not affected.

Place explicit calls to phy_start() and phy_stop() before enabling or after
disabling an attached SFP module, where phydev is not yet set (or is
already unset), so they will be made only from the inside of sfp-bus, if
needed.

Fixes: 21796261 ("net: phy: warn if phy_start is called from invalid state")
Signed-off-by: Arseny Solokha <asolokha@kb.kras.ru>
Acked-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

Merge tag 'linux-can-fixes-for-5.3-20190724' of git://git.kernel.org/pub/scm/linux/kernel/git/mkl/linux-can

Marc Kleine-Budde says:

====================
pull-request: can 2019-07-24

this is a pull reqeust of 7 patches for net/master.

The first patch is by Rasmus Villemoes add a missing netif_carrier_off() to
register_candev() so that generic netdev trigger based LEDs are initially off.

Nikita Yushchenko's patch for the rcar_canfd driver fixes a possible IRQ storm
on high load.

The patch by Weitao Hou for the mcp251x driver add missing error checking to
the work queue allocation.

Both Wen Yang's and Joakim Zhang's patch for the flexcan driver fix a problem
with the stop-mode.

Stephane Grosjean contributes a patch for the peak_usb driver to fix a
potential double kfree_skb().

The last patch is by YueHaibing and fixes the error path in can-gw's
cgw_module_init() function.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Since ip6_tnl_parse_tlv_enc_lim() can call pskb_may_pull()
which may change skb->data, so we need to re-load ipv6h at
the right place.

Fixes: 898b2979 ("ip6_gre: Refactor ip6gre xmit codes")
Cc: William Tu <u9012063@gmail.com>
Signed-off-by: Haishuang Yan <yanhaishuang@cmss.chinamobile.com>
Acked-by: William Tu <u9012063@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Cleanup testing for error condition.
Signed-off-by: Pavel Machek <pavel@denx.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

This patch add error path for cgw_module_init to avoid possible crash if
some error occurs.

Fixes: c1aabdf3 ("can-gw: add netlink based CAN routing")
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Acked-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

When closing the CAN device while tx skbs are inflight, echo skb could
be released twice. By calling close_candev() before unlinking all
pending tx urbs, then the internal echo_skb[] array is fully and
correctly cleared before the USB write callback and, therefore,
can_get_echo_skb() are called, for each aborted URB.

Fixes: bb478555 ("can: usb: PEAK-System Technik USB adapters driver core")
Signed-off-by: Stephane Grosjean <s.grosjean@peak-system.com>
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

To enter stop mode, the CPU should manually assert a global Stop Mode
request and check the acknowledgment asserted by FlexCAN. The CPU must
only consider the FlexCAN in stop mode when both request and
acknowledgment conditions are satisfied.

Fixes: de3578c1 ("can: flexcan: add self wakeup support")
Reported-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Joakim Zhang <qiangqing.zhang@nxp.com>
Cc: linux-stable <stable@vger.kernel.org> # >= v5.0
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

The gpr_np variable is still being used in dev_dbg() after the
of_node_put() call, which may result in use-after-free.

Fixes: de3578c1 ("can: flexcan: add self wakeup support")
Signed-off-by: Wen Yang <wen.yang99@zte.com.cn>
Cc: linux-stable <stable@vger.kernel.org> # >= v5.0
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

add error check when workqueue alloc failed, and remove redundant code
to make it clear.

Fixes: e0000163 ("can: Driver for the Microchip MCP251x SPI CAN controllers")
Signed-off-by: Weitao Hou <houweitaoo@gmail.com>
Acked-by: Willem de Bruijn <willemb@google.com>
Tested-by: Sean Nyekjaer <sean@geanix.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

We have observed rcar_canfd driver entering IRQ storm under high load,
with following scenario:
- rcar_canfd_global_interrupt() in entered due to Rx available,
- napi_schedule_prep() is called, and sets NAPIF_STATE_SCHED in state
- Rx fifo interrupts are masked,
- rcar_canfd_global_interrupt() is entered again, this time due to
  error interrupt (e.g. due to overflow),
- since scheduled napi poller has not yet executed, condition for calling
  napi_schedule_prep() from rcar_canfd_global_interrupt() remains true,
  thus napi_schedule_prep() gets called and sets NAPIF_STATE_MISSED flag
  in state,
- later, napi poller function rcar_canfd_rx_poll() gets executed, and
  calls napi_complete_done(),
- due to NAPIF_STATE_MISSED flag in state, this call does not clear
  NAPIF_STATE_SCHED flag from state,
- on return from napi_complete_done(), rcar_canfd_rx_poll() unmasks Rx
  interrutps,
- Rx interrupt happens, rcar_canfd_global_interrupt() gets called
  and calls napi_schedule_prep(),
- since NAPIF_STATE_SCHED is set in state at this time, this call
  returns false,
- due to that false return, rcar_canfd_global_interrupt() returns
  without masking Rx interrupt
- and this results into IRQ storm: unmasked Rx interrupt happens again
  and again is misprocessed in the same way.

This patch fixes that scenario by unmasking Rx interrupts only when
napi_complete_done() returns true, which means it has cleared
NAPIF_STATE_SCHED in state.

Fixes: dd3bd23e ("can: rcar_canfd: Add Renesas R-Car CAN FD driver")
Signed-off-by: Nikita Yushchenko <nikita.yoush@cogentembedded.com>
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

CONFIG_CAN_LEDS is deprecated. When trying to use the generic netdev
trigger as suggested, there's a small inconsistency with the link
property: The LED is on initially, stays on when the device is brought
up, and then turns off (as expected) when the device is brought down.

Make sure the LED always reflects the state of the CAN device.
Signed-off-by: Rasmus Villemoes <rasmus.villemoes@prevas.dk>
Acked-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

Replace the custom implementation with fwnode_get_mac_address,
which works on both DT and ACPI platforms.

While here, replace memcpy() by ether_addr_copy().
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The onboard sky2 NIC on ASUS P6T WS PRO doesn't work after PM resume
due to the infamous IRQ problem.  Disabling MSI works around it, so
let's add it to the blacklist.

Unfortunately the BIOS on the machine doesn't fill the standard
DMI_SYS_* entry, so we pick up DMI_BOARD_* entries instead.

BugLink: https://bugzilla.suse.com/show_bug.cgi?id=1142496Reported-and-tested-by: Marcus Seyfarth <m.seyfarth@gmail.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

Each iteration of for_each_child_of_node puts the previous node, but in
the case of a return from the middle of the loop, there is no put, thus
causing a memory leak. Hence add an of_node_put before the return.
Issue found with Coccinelle.
Signed-off-by: Nishka Dasgupta <nishkadg.linux@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Each iteration of for_each_available_child_of_node puts the previous
node, but in the case of a return from the middle of the loop, there is
no put, thus causing a memory leak. Hence add an of_node_put before the
return.
Issue found with Coccinelle.
Signed-off-by: Nishka Dasgupta <nishkadg.linux@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Ido Schimmel says:

====================
selftests: forwarding: GRE multipath fixes

Patch #1 ensures IPv4 forwarding is enabled during the test.

Patch #2 fixes the flower filters used to measure the distribution of
the traffic between the two nexthops, so that the test will pass
regardless if traffic is offloaded or not.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

The TC filters used in the test do not work with veth devices because the
outer Ethertype is 802.1Q and not IPv4. The test passes with mlxsw
netdevs since the hardware always looks at "The first Ethertype that
does not point to either: VLAN, CNTAG or configurable Ethertype".

Fix this by matching on the VLAN ID instead, but on the ingress side.
The reason why this is not performed at egress is explained in the
commit cited below.

Fixes: 541ad323 ("selftests: forwarding: gre_multipath: Update next-hop statistics match criteria")
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Reported-by: Stephen Suryaputra <ssuryaextr@gmail.com>
Tested-by: Stephen Suryaputra <ssuryaextr@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The test did not enable IPv4 forwarding during its setup phase, which
causes the test to fail on machines where IPv4 forwarding is disabled.

Fixes: 54818c4c ("selftests: forwarding: Test multipath tunneling")
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Reported-by: Stephen Suryaputra <ssuryaextr@gmail.com>
Tested-by: Stephen Suryaputra <ssuryaextr@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

This reverts commit f4e5f775.

Andrew Lunn says this should be handled another way.
Signed-off-by: David S. Miller <davem@davemloft.net>

Some glue logic drivers support 1G without having GMAC/GMAC4/XGMAC.

Let's allow this speed by default.
Reported-by: Ondrej Jirman <megi@xff.cz>
Tested-by: Ondrej Jirman <megi@xff.cz>
Fixes: 5b0d7d7d ("net: stmmac: Add the missing speeds that XGMAC supports")
Signed-off-by: Jose Abreu <joabreu@synopsys.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Jose Abreu says:

====================
net: stmmac: Two fixes

Two fixes targeting -net.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

We need the memory to be zeroed upon allocation so use kcalloc()
instead.
Signed-off-by: Jose Abreu <joabreu@synopsys.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

RX Descriptors are being cleaned after setting the buffers which may
lead to buffer addresses being wiped out.

Fix this by clearing earlier the RX Descriptors.

Fixes: 2af6106a ("net: stmmac: Introducing support for Page Pool")
Signed-off-by: Jose Abreu <joabreu@synopsys.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Since commit(net: phy: marvell: change default m88e1510 LED configuration),
the active LED of Hip07 devices is always off, because Hip07 just
use 2 LEDs.
This patch adds a phy_register_fixup_for_uid() for m88e1510 to
correct the LED configuration.

Fixes: 07777246 ("net: phy: marvell: change default m88e1510 LED configuration")
Signed-off-by: Yonglong Liu <liuyonglong@huawei.com>
Reviewed-by: linyunsheng <linyunsheng@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

PPv2's XLGMAC can wait for 3 idle frames before triggering a link up
event. This can cause the link to be stuck low when there's traffic on
the interface, so disable this feature.

Fixes: 4bb04326 ("net: mvpp2: phylink support")
Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The following scenario was encountered during testing of logical
partition mobility on pseries partitions with bonded ibmvnic
adapters in LACP mode.

1. Driver receives a signal that the device has been
   swapped, and it needs to reset to initialize the new
   device.

2. Driver reports loss of carrier and begins initialization.

3. Bonding driver receives NETDEV_CHANGE notifier and checks
   the slave's current speed and duplex settings. Because these
   are unknown at the time, the bond sets its link state to
   BOND_LINK_FAIL and handles the speed update, clearing
   AD_PORT_LACP_ENABLE.

4. Driver finishes recovery and reports that the carrier is on.

5. Bond receives a new notification and checks the speed again.
   The speeds are valid but miimon has not altered the link
   state yet.  AD_PORT_LACP_ENABLE remains off.

Because the slave's link state is still BOND_LINK_FAIL,
no further port checks are made when it recovers. Though
the slave devices are operational and have valid speed
and duplex settings, the bond will not send LACPDU's. The
simplest fix I can see is to force another speed check
in bond_miimon_commit. This way the bond will update
AD_PORT_LACP_ENABLE if needed when transitioning from
BOND_LINK_FAIL to BOND_LINK_UP.

CC: Jarod Wilson <jarod@redhat.com>
CC: Jay Vosburgh <j.vosburgh@gmail.com>
CC: Veaceslav Falico <vfalico@gmail.com>
CC: Andy Gospodarek <andy@greyhouse.net>
Signed-off-by: Thomas Falcon <tlfalcon@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Pull preemption Kconfig fix from Thomas Gleixner:
 "The PREEMPT_RT stub config renamed PREEMPT to PREEMPT_LL and defined
  PREEMPT outside of the menu and made it selectable by both PREEMPT_LL
  and PREEMPT_RT.

  Stupid me missed that 114 defconfigs select CONFIG_PREEMPT which
  obviously can't work anymore. oldconfig builds are affected as well,
  but it's more obvious as the user gets asked. [old]defconfig silently
  fixes it up and selects PREEMPT_NONE.

  Unbreak it by undoing the rename and adding a intermediate config
  symbol which is selected by both PREEMPT and PREEMPT_RT. That requires
  to chase down a few #ifdefs, but it's better than tweaking 114
  defconfigs and annoying users"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/rt, Kconfig: Unbreak def/oldconfig with CONFIG_PREEMPT=y

Pull pidfd polling fix from Christian Brauner:
 "A fix for pidfd polling. It ensures that the task's exit state is
  visible to all waiters"

* tag 'for-linus-20190722' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux:
  pidfd: fix a poll race when setting exit_state

Pull btrfs fixes from David Sterba:

 - fixes for leaks caused by recently merged patches

 - one build fix

 - a fix to prevent mixing of incompatible features

* tag 'for-5.3-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  btrfs: don't leak extent_map in btrfs_get_io_geometry()
  btrfs: free checksum hash on in close_ctree
  btrfs: Fix build error while LIBCRC32C is module
  btrfs: inode: Don't compress if NODATASUM or NODATACOW set

The merge of the CONFIG_PREEMPT_RT stub renamed CONFIG_PREEMPT to
CONFIG_PREEMPT_LL which causes all defconfigs which have CONFIG_PREEMPT=y
set to fall back to CONFIG_PREEMPT_NONE because CONFIG_PREEMPT depends on
the preemption mode choice wich defaults to NONE. This also affects
oldconfig builds.

So rather than changing 114 defconfig files and being an annoyance to
users, revert the rename and select a new config symbol PREEMPTION. That
keeps everything working smoothly and the revelant ifdef's are going to be
fixed up step by step.
Reported-by: Mark Rutland <mark.rutland@arm.com>
Fixes: a50a3f4b ("sched/rt, Kconfig: Introduce CONFIG_PREEMPT_RT")
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

Pull media fixes from Mauro Carvalho Chehab:
 "For two regressions in media core:

   - v4l2-subdev: fix regression in check_pad()

   - videodev2.h: change V4L2_PIX_FMT_BGRA444 define: fourcc was already
     in use"

* tag 'media/v5.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media:
  media: videodev2.h: change V4L2_PIX_FMT_BGRA444 define: fourcc was already in use
  media: v4l2-subdev: fix regression in check_pad()

Pull networking fixes from David Miller:

 1) Several netfilter fixes including a nfnetlink deadlock fix from
    Florian Westphal and fix for dropping VRF packets from Miaohe Lin.

 2) Flow offload fixes from Pablo Neira Ayuso including a fix to restore
    proper block sharing.

 3) Fix r8169 PHY init from Thomas Voegtle.

 4) Fix memory leak in mac80211, from Lorenzo Bianconi.

 5) Missing NULL check on object allocation in cxgb4, from Navid
    Emamdoost.

 6) Fix scaling of RX power in sfp phy driver, from Andrew Lunn.

 7) Check that there is actually an ip header to access in skb->data in
    VRF, from Peter Kosyh.

 8) Remove spurious rcu unlock in hv_netvsc, from Haiyang Zhang.

 9) One more tweak the the TCP fragmentation memory limit changes, to be
    less harmful to applications setting small SO_SNDBUF values. From
    Eric Dumazet.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (40 commits)
  tcp: be more careful in tcp_fragment()
  hv_netvsc: Fix extra rcu_read_unlock in netvsc_recv_callback()
  vrf: make sure skb->data contains ip header to make routing
  connector: remove redundant input callback from cn_dev
  qed: Prefer pcie_capability_read_word()
  igc: Prefer pcie_capability_read_word()
  cxgb4: Prefer pcie_capability_read_word()
  be2net: Synchronize be_update_queues with dev_watchdog
  bnx2x: Prevent load reordering in tx completion processing
  net: phy: sfp: hwmon: Fix scaling of RX power
  net: sched: verify that q!=NULL before setting q->flags
  chelsio: Fix a typo in a function name
  allocate_flower_entry: should check for null deref
  net: hns3: typo in the name of a constant
  kbuild: add net/netfilter/nf_tables_offload.h to header-test blacklist.
  tipc: Fix a typo
  mac80211: don't warn about CW params when not using them
  mac80211: fix possible memory leak in ieee80211_assign_beacon
  nl80211: fix NL80211_HE_MAX_CAPABILITY_LEN
  nl80211: fix VENDOR_CMD_RAW_DATA
  ...

There is a race between reading task->exit_state in pidfd_poll and
writing it after do_notify_parent calls do_notify_pidfd. Expected
sequence of events is:

CPU 0                            CPU 1
------------------------------------------------
exit_notify
  do_notify_parent
    do_notify_pidfd
  tsk->exit_state = EXIT_DEAD
                                  pidfd_poll
                                     if (tsk->exit_state)

However nothing prevents the following sequence:

CPU 0                            CPU 1
------------------------------------------------
exit_notify
  do_notify_parent
    do_notify_pidfd
                                   pidfd_poll
                                      if (tsk->exit_state)
  tsk->exit_state = EXIT_DEAD

This causes a polling task to wait forever, since poll blocks because
exit_state is 0 and the waiting task is not notified again. A stress
test continuously doing pidfd poll and process exits uncovered this bug.

To fix it, we make sure that the task's exit_state is always set before
calling do_notify_pidfd.

Fixes: b53b0b9d ("pidfd: add polling support")
Cc: kernel-team@android.com
Cc: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Link: https://lore.kernel.org/r/20190717172100.261204-1-joel@joelfernandes.org
[christian@brauner.io: adapt commit message and drop unneeded changes from wait_task_zombie]
Signed-off-by: Christian Brauner <christian@brauner.io>

Some applications set tiny SO_SNDBUF values and expect
TCP to just work. Recent patches to address CVE-2019-11478
broke them in case of losses, since retransmits might
be prevented.

We should allow these flows to make progress.

This patch allows the first and last skb in retransmit queue
to be split even if memory limits are hit.

It also adds the some room due to the fact that tcp_sendmsg()
and tcp_sendpage() might overshoot sk_wmem_queued by about one full
TSO skb (64KB size). Note this allowance was already present
in stable backports for kernels < 4.15

Note for < 4.15 backports :
 tcp_rtx_queue_tail() will probably look like :

static inline struct sk_buff *tcp_rtx_queue_tail(const struct sock *sk)
{
	struct sk_buff *skb = tcp_send_head(sk);

	return skb ? tcp_write_queue_prev(sk, skb) : tcp_write_queue_tail(sk);
}

Fixes: f070ef2a ("tcp: tcp_fragment() should apply sane memory limits")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Andrew Prout <aprout@ll.mit.edu>
Tested-by: Andrew Prout <aprout@ll.mit.edu>
Tested-by: Jonathan Lemon <jonathan.lemon@gmail.com>
Tested-by: Michal Kubecek <mkubecek@suse.cz>
Acked-by: Neal Cardwell <ncardwell@google.com>
Acked-by: Yuchung Cheng <ycheng@google.com>
Acked-by: Christoph Paasch <cpaasch@apple.com>
Cc: Jonathan Looney <jtl@netflix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

There is an extra rcu_read_unlock left in netvsc_recv_callback(),
after a previous patch that removes RCU from this function.
This patch removes the extra RCU unlock.

Fixes: 345ac089 ("hv_netvsc: pass netvsc_device to receive callback")
Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

vrf_process_v4_outbound() and vrf_process_v6_outbound() do routing
using ip/ipv6 addresses, but don't make sure the header is available
in skb->data[] (skb_headlen() is less then header size).

Case:

1) igb driver from intel.
2) Packet size is greater then 255.
3) MPLS forwards to VRF device.

So, patch adds pskb_may_pull() calls in vrf_process_v4/v6_outbound()
functions.
Signed-off-by: Peter Kosyh <p.kosyh@gmail.com>
Reviewed-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

A small cleanup: this callback is never used.
Originally fixed by Stanislav Kinsburskiy <skinsbursky@virtuozzo.com>
for OpenVZ7 bug OVZ-6877

cc: stanislav.kinsburskiy@gmail.com
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Commit 8c0d3a02 ("PCI: Add accessors for PCI Express Capability")
added accessors for the PCI Express Capability so that drivers didn't
need to be aware of differences between v1 and v2 of the PCI
Express Capability.

Replace pci_read_config_word() and pci_write_config_word() calls with
pcie_capability_read_word() and pcie_capability_write_word().
Signed-off-by: Frederick Lawler <fred@fredlawl.com>
Acked-by: Michal Kalderon <michal.kalderon@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Commit 8c0d3a02 ("PCI: Add accessors for PCI Express Capability")
added accessors for the PCI Express Capability so that drivers didn't
need to be aware of differences between v1 and v2 of the PCI
Express Capability.

Replace pci_read_config_word() and pci_write_config_word() calls with
pcie_capability_read_word() and pcie_capability_write_word().
Signed-off-by: Frederick Lawler <fred@fredlawl.com>
Signed-off-by: David S. Miller <davem@davemloft.net>