We should not trigger a warning when a memory allocation fails. Remove
the WARN_ON().

The warning is constantly triggered by syzkaller when it is injecting
faults:

[ 2230.758664] FAULT_INJECTION: forcing a failure.
[ 2230.758664] name failslab, interval 1, probability 0, space 0, times 0
[ 2230.762329] CPU: 3 PID: 1407 Comm: syz-executor.0 Not tainted 5.8.0-rc2+ #28
...
[ 2230.898175] WARNING: CPU: 3 PID: 1407 at drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c:6265 mlxsw_sp_router_fib_event+0xfad/0x13e0
[ 2230.898179] Kernel panic - not syncing: panic_on_warn set ...
[ 2230.898183] CPU: 3 PID: 1407 Comm: syz-executor.0 Not tainted 5.8.0-rc2+ #28
[ 2230.898190] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.1-0-ga5cab58e9a3f-prebuilt.qemu.org 04/01/2014

Fixes: 3057224e ("mlxsw: spectrum_router: Implement FIB offload in deferred work")
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Nicolas Ferre says:

====================
net: macb: Wake-on-Lan magic packet fixes and GEM handling

Here is a split series to fix WoL magic-packet on the current macb driver. Only
fixes in this one based on current net/master.

Changes in v5:
- Addressed the error code returned by phylink_ethtool_set_wol() as suggested
  by Russell.
  If PHY handles WoL, MAC doesn't stay in the way.
- Removed Florian's tag on 3/5 because of the above changes.
- Correct the "Fixes" tag on 1/5.

Changes in v4:
- Pure bug fix series for 'net'. GEM addition and MACB update removed: will be
  sent later.

Changes in v3:
- Revert some of the v2 changes done in macb_resume(). Now the resume function
  supports in-depth re-configuration of the controller in order to deal with
  deeper sleep states. Basically as it was before changes introduced by this
  series
- Tested for non-regression with our deeper Power Management mode which cuts
  power to the controller completely

Changes in v2:
- Add patch 4/7 ("net: macb: fix macb_suspend() by removing call to netif_carrier_off()")
  needed for keeping phy state consistent
- Add patch 5/7 ("net: macb: fix call to pm_runtime in the suspend/resume functions") that prevent
  putting the macb in runtime pm suspend mode when WoL is used
- Collect review tags on 3 first patches from Florian: Thanks!
- Review of macb_resume() function
- Addition of pm_wakeup_event() in both MACB and GEM WoL IRQ handlers
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

The calls to pm_runtime_force_suspend/resume() functions are only
relevant if the device is not configured to act as a WoL wakeup source.
Add the device_may_wakeup() test before calling them.

Fixes: 3e2a5e15 ("net: macb: add wake-on-lan support via magic packet")
Cc: Claudiu Beznea <claudiu.beznea@microchip.com>
Cc: Harini Katakam <harini.katakam@xilinx.com>
Cc: Sergio Prado <sergio.prado@e-labworks.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

As we now use the phylink call to phylink_stop() in the non-WoL path,
there is no need for this call to netif_carrier_off() anymore. It can
disturb the underlying phylink FSM.

Fixes: 7897b071 ("net: macb: convert to phylink")
Cc: Claudiu Beznea <claudiu.beznea@microchip.com>
Cc: Harini Katakam <harini.katakam@xilinx.com>
Cc: Antoine Tenart <antoine.tenart@bootlin.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Keep previous function goals and integrate phylink actions to them.

phylink_ethtool_get_wol() is not enough to figure out if Ethernet driver
supports Wake-on-Lan.
Initialization of "supported" and "wolopts" members is done in phylink
function, no need to keep them in calling function.

phylink_ethtool_set_wol() return value is considered and determines
if the MAC has to handle WoL or not. The case where the PHY doesn't
implement WoL leads to the MAC configuring it to provide this feature.

Fixes: 7897b071 ("net: macb: convert to phylink")
Cc: Claudiu Beznea <claudiu.beznea@microchip.com>
Cc: Harini Katakam <harini.katakam@xilinx.com>
Cc: Antoine Tenart <antoine.tenart@bootlin.com>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Change the way the "magic-packet" DT property is handled in the
macb_probe() function, matching DT binding documentation.
Now we mark the device as "wakeup capable" instead of calling the
device_init_wakeup() function that would enable the wakeup source.

For Ethernet WoL, enabling the wakeup_source is done by
using ethtool and associated macb_set_wol() function that
already calls device_set_wakeup_enable() for this purpose.

That would reduce power consumption by cutting more clocks if
"magic-packet" property is set but WoL is not configured by ethtool.

Fixes: 3e2a5e15 ("net: macb: add wake-on-lan support via magic packet")
Cc: Claudiu Beznea <claudiu.beznea@microchip.com>
Cc: Harini Katakam <harini.katakam@xilinx.com>
Cc: Sergio Prado <sergio.prado@e-labworks.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Use the proper struct device pointer to check if the wakeup flag
and wakeup source are positioned.
Use the one passed by function call which is equivalent to
&bp->dev->dev.parent.

It's preventing the trigger of a spurious interrupt in case the
Wake-on-Lan feature is used.

Fixes: d54f89af ("net: macb: Add pm runtime support")
Cc: Claudiu Beznea <claudiu.beznea@microchip.com>
Cc: Harini Katakam <harini.katakam@xilinx.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

we need to set 'active_vfs' back to 0, if something goes wrong during the
allocation of SR-IOV resources: otherwise, further VF configurations will
wrongly assume that bp->pf.vf[x] are valid memory locations, and commands
like the ones in the following sequence:

 # echo 2 >/sys/bus/pci/devices/${ADDR}/sriov_numvfs
 # ip link set dev ens1f0np0 up
 # ip link set dev ens1f0np0 vf 0 trust on

will cause a kernel crash similar to this:

 bnxt_en 0000:3b:00.0: not enough MMIO resources for SR-IOV
 BUG: kernel NULL pointer dereference, address: 0000000000000014
 #PF: supervisor read access in kernel mode
 #PF: error_code(0x0000) - not-present page
 PGD 0 P4D 0
 Oops: 0000 [#1] SMP PTI
 CPU: 43 PID: 2059 Comm: ip Tainted: G          I       5.8.0-rc2.upstream+ #871
 Hardware name: Dell Inc. PowerEdge R740/08D89F, BIOS 2.2.11 06/13/2019
 RIP: 0010:bnxt_set_vf_trust+0x5b/0x110 [bnxt_en]
 Code: 44 24 58 31 c0 e8 f5 fb ff ff 85 c0 0f 85 b6 00 00 00 48 8d 1c 5b 41 89 c6 b9 0b 00 00 00 48 c1 e3 04 49 03 9c 24 f0 0e 00 00 <8b> 43 14 89 c2 83 c8 10 83 e2 ef 45 84 ed 49 89 e5 0f 44 c2 4c 89
 RSP: 0018:ffffac6246a1f570 EFLAGS: 00010246
 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 000000000000000b
 RDX: 0000000000000001 RSI: 0000000000000000 RDI: ffff98b28f538900
 RBP: ffff98b28f538900 R08: 0000000000000000 R09: 0000000000000008
 R10: ffffffffb9515be0 R11: ffffac6246a1f678 R12: ffff98b28f538000
 R13: 0000000000000001 R14: 0000000000000000 R15: ffffffffc05451e0
 FS:  00007fde0f688800(0000) GS:ffff98baffd40000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 0000000000000014 CR3: 000000104bb0a003 CR4: 00000000007606e0
 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
 PKRU: 55555554
 Call Trace:
  do_setlink+0x994/0xfe0
  __rtnl_newlink+0x544/0x8d0
  rtnl_newlink+0x47/0x70
  rtnetlink_rcv_msg+0x29f/0x350
  netlink_rcv_skb+0x4a/0x110
  netlink_unicast+0x21d/0x300
  netlink_sendmsg+0x329/0x450
  sock_sendmsg+0x5b/0x60
  ____sys_sendmsg+0x204/0x280
  ___sys_sendmsg+0x88/0xd0
  __sys_sendmsg+0x5e/0xa0
  do_syscall_64+0x47/0x80
  entry_SYSCALL_64_after_hwframe+0x44/0xa9

Fixes: c0c050c5 ("bnxt_en: New Broadcom ethernet driver.")
Reported-by: Fei Liu <feliu@redhat.com>
CC: Jonathan Toppins <jtoppins@redhat.com>
CC: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Reviewed-by: Michael Chan <michael.chan@broadcom.com>
Acked-by: Jonathan Toppins <jtoppins@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Alexei Starovoitov says:

====================
pull-request: bpf 2020-07-09

The following pull-request contains BPF updates for your *net* tree.

We've added 4 non-merge commits during the last 1 day(s) which contain
a total of 4 files changed, 26 insertions(+), 15 deletions(-).

The main changes are:

1) fix crash in libbpf on 32-bit archs, from Jakub and Andrii.

2) fix crash when l2tp and bpf_sk_reuseport conflict, from Martin.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Saeed Mahameed says:

====================
mlx5 fixes 2020-07-02

This series introduces some fixes to mlx5 driver.

V1->v2:
 - Drop "ip -s" patch and mirred device hold reference patch.
 - Will revise them in a later submission.

Please pull and let me know if there is any problem.

For -stable v5.2
 ('net/mlx5: Fix eeprom support for SFP module')

For -stable v5.4
 ('net/mlx5e: Fix 50G per lane indication')

For -stable v5.5
 ('net/mlx5e: Fix CPU mapping after function reload to avoid aRFS RX crash')
 ('net/mlx5e: Fix VXLAN configuration restore after function reload')

For -stable v5.7
 ('net/mlx5e: CT: Fix memory leak in cleanup')
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

On ILP32, 64-bit result was shifted by value calculated for 32-bit long type
and returned value was much outside hashmap capacity.
As advised by Andrii Nakryiko, this patch uses different hashing variant for
architectures with size_t shorter than long long.

Fixes: e3b92422 ("libbpf: add resizable non-thread safe internal hashmap")
Signed-off-by: Jakub Bogusz <qboosh@pld-linux.org>
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200709225723.1069937-1-andriin@fb.com

CT entries are deleted via a workqueue from netfilter. If removing the
module before that, the rules are cleaned by the driver itself, but the
memory entries for them are not freed. Fix that.

Fixes: ac991b48 ("net/mlx5e: CT: Offload established flows")
Signed-off-by: Eli Britstein <elibr@mellanox.com>
Reviewed-by: Roi Dayan <roid@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>

Device unit for port buffers size, xoff_threshold and xon_threshold is
cells. Fix a bug in driver where cell unit size was hard-coded to
128 bytes. This hard-coded value is buggy, as it is wrong for some hardware
versions.

Driver to read cell size from SBCAM register and translate bytes to cell
units accordingly.

In order to fix the bug, this patch exposes SBCAM (Shared buffer
capabilities mask) layout and defines.

If SBCAM.cap_cell_size is valid, use it for all bytes to cells
calculations. If not valid, fallback to 128.

Cell size do not change on the fly per device. Instead of issuing SBCAM
access reg command every time such translation is needed, cache it in
mlx5e_dcbx as part of mlx5e_dcbnl_initialize(). Pass dcbx.port_buff_cell_sz
as a param to every function that needs bytes to cells translation.

While fixing the bug, move MLX5E_BUFFER_CELL_SHIFT macro to
en_dcbnl.c, as it is only used by that file.

Fixes: 0696d608 ("net/mlx5e: Receive buffer configuration")
Signed-off-by: Eran Ben Elisha <eranbe@mellanox.com>
Reviewed-by: Huy Nguyen <huyn@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>

Some released FW versions mistakenly don't set the capability that 50G
per lane link-modes are supported for VFs (ptys_extended_ethernet
capability bit). When the capability is unset, read
PTYS.ext_eth_proto_capability (always reliable).
If PTYS.ext_eth_proto_capability is valid (has a non-zero value)
conclude that the HCA supports 50G per lane. Otherwise, conclude that
the HCA doesn't support 50G per lane.

Fixes: a08b4ed1 ("net/mlx5: Add support to ext_* fields introduced in Port Type and Speed register")
Signed-off-by: Aya Levin <ayal@mellanox.com>
Reviewed-by: Eran Ben Elisha <eranbe@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>

After function reload, CPU mapping used by aRFS RX is broken, leading to
a kernel panic. Fix by moving initialization of rx_cpu_rmap from
netdev_init to netdev_attach. IRQ table is re-allocated on mlx5_load,
but netdev is not re-initialize.

Trace of the panic:
[ 22.055672] general protection fault, probably for non-canonical address 0x785634120000ff1c: 0000 [#1] SMP PTI
[ 22.065010] CPU: 4 PID: 0 Comm: swapper/4 Not tainted 5.7.0-rc2-for-upstream-perf-2020-04-21_16-34-03-31 #1
[ 22.067967] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.12.1-0-ga5cab58e9a3f-prebuilt.qemu.org 04/01/2014
[ 22.071174] RIP: 0010:get_rps_cpu+0x267/0x300
[ 22.075692] RSP: 0018:ffffc90000244d60 EFLAGS: 00010202
[ 22.076888] RAX: ffff888459b0e400 RBX: 0000000000000000 RCX:0000000000000007
[ 22.078364] RDX: 0000000000008884 RSI: ffff888467cb5b00 RDI:0000000000000000
[ 22.079815] RBP: 00000000ff342b27 R08: 0000000000000007 R09:0000000000000003
[ 22.081289] R10: ffffffffffffffff R11: 00000000000070cc R12:ffff888454900000
[ 22.082767] R13: ffffc90000e5a950 R14: ffffc90000244dc0 R15:0000000000000007
[ 22.084190] FS: 0000000000000000(0000) GS:ffff88846fc80000(0000)knlGS:0000000000000000
[ 22.086161] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 22.087427] CR2: ffffffffffffffff CR3: 0000000464426003 CR4:0000000000760ee0
[ 22.088888] DR0: 0000000000000000 DR1: 0000000000000000 DR2:0000000000000000
[ 22.090336] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7:0000000000000400
[ 22.091764] PKRU: 55555554
[ 22.092618] Call Trace:
[ 22.093442] <IRQ>
[ 22.094211] ? kvm_clock_get_cycles+0xd/0x10
[ 22.095272] netif_receive_skb_list_internal+0x258/0x2a0
[ 22.096460] gro_normal_list.part.137+0x19/0x40
[ 22.097547] napi_complete_done+0xc6/0x110
[ 22.098685] mlx5e_napi_poll+0x190/0x670 [mlx5_core]
[ 22.099859] net_rx_action+0x2a0/0x400
[ 22.100848] __do_softirq+0xd8/0x2a8
[ 22.101829] irq_exit+0xa5/0xb0
[ 22.102750] do_IRQ+0x52/0xd0
[ 22.103654] common_interrupt+0xf/0xf
[ 22.104641] </IRQ>

Fixes: 4383cfcc ("net/mlx5: Add devlink reload")
Signed-off-by: Aya Levin <ayal@mellanox.com>
Reviewed-by: Eran Ben Elisha <eranbe@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>

When detaching netdev, remove vxlan port configuration using
udp_tunnel_drop_rx_info. During function reload, configuration will be
restored using udp_tunnel_get_rx_info. This ensures sync between
firmware and driver. Use udp_tunnel_get_rx_info even if its physical
interface is down.

Fixes: 4383cfcc ("net/mlx5: Add devlink reload")
Signed-off-by: Aya Levin <ayal@mellanox.com>
Reviewed-by: Eran Ben Elisha <eranbe@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>

In mlx5e_configure_flower() flow pointer is protected by rcu read lock.
However, after cited commit the pointer is being used outside of rcu read
block. Extend the block to protect all pointer accesses.

Fixes: 553f9328 ("net/mlx5e: Support tc block sharing for representors")
Signed-off-by: Vlad Buslov <vladbu@mellanox.com>
Reviewed-by: Roi Dayan <roid@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>

In helper function is_flow_rule_duplicate_allowed() verify that rpviv
pointer is not NULL before dereferencing it. This can happen when device is
in NIC mode and leads to following crash:

[90444.046419] BUG: kernel NULL pointer dereference, address: 0000000000000000
[90444.048149] #PF: supervisor read access in kernel mode
[90444.049781] #PF: error_code(0x0000) - not-present page
[90444.051386] PGD 80000003d35a4067 P4D 80000003d35a4067 PUD 3d35a3067 PMD 0
[90444.053051] Oops: 0000 [#1] SMP PTI
[90444.054683] CPU: 16 PID: 31736 Comm: tc Not tainted 5.8.0-rc1+ #1157
[90444.056340] Hardware name: Supermicro SYS-2028TP-DECR/X10DRT-P, BIOS 2.0b 03/30/2017
[90444.058079] RIP: 0010:mlx5e_configure_flower+0x3aa/0x9b0 [mlx5_core]
[90444.059753] Code: 24 50 49 8b 95 08 02 00 00 48 b8 00 08 00 00 04 00 00 00 48 21 c2 48 39 c2 74 0a 41 f6 85 0d 02 00 00 20 74 16 48 8b 44 24 20 <48> 8b 00 66 83 78 20 ff 74 07 4d 89 aa e0 00 00 00 48 83 7d 28 00
[90444.063232] RSP: 0018:ffffabe9c61ff768 EFLAGS: 00010246
[90444.065014] RAX: 0000000000000000 RBX: ffff9b13c4c91e80 RCX: 00000000000093fa
[90444.066784] RDX: 0000000400000800 RSI: 0000000000000000 RDI: 000000000002d5e0
[90444.068533] RBP: ffff9b174d308468 R08: 0000000000000000 R09: ffff9b17d63003f0
[90444.070285] R10: ffff9b17ea288600 R11: 0000000000000000 R12: ffffabe9c61ff878
[90444.072032] R13: ffff9b174d300000 R14: ffffabe9c61ffbb8 R15: ffff9b174d300880
[90444.073760] FS:  00007f3c23775480(0000) GS:ffff9b13efc80000(0000) knlGS:0000000000000000
[90444.075492] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[90444.077266] CR2: 0000000000000000 CR3: 00000003e2a60002 CR4: 00000000001606e0
[90444.079024] Call Trace:
[90444.080753]  tc_setup_cb_add+0xca/0x1e0
[90444.082415]  fl_hw_replace_filter+0x15f/0x1f0 [cls_flower]
[90444.084119]  fl_change+0xa59/0x13dc [cls_flower]
[90444.085772]  ? wait_for_completion+0xa8/0xf0
[90444.087364]  tc_new_tfilter+0x3f5/0xa60
[90444.088960]  rtnetlink_rcv_msg+0xeb/0x360
[90444.090514]  ? __d_lookup_done+0x76/0xe0
[90444.092034]  ? proc_alloc_inode+0x16/0x70
[90444.093560]  ? prep_new_page+0x8c/0xf0
[90444.095048]  ? _cond_resched+0x15/0x30
[90444.096483]  ? rtnl_calcit.isra.0+0x110/0x110
[90444.097907]  netlink_rcv_skb+0x49/0x110
[90444.099289]  netlink_unicast+0x191/0x230
[90444.100629]  netlink_sendmsg+0x243/0x480
[90444.101984]  sock_sendmsg+0x5e/0x60
[90444.103305]  ____sys_sendmsg+0x1f3/0x260
[90444.104597]  ? copy_msghdr_from_user+0x5c/0x90
[90444.105916]  ? __mod_lruvec_state+0x3c/0xe0
[90444.107210]  ___sys_sendmsg+0x81/0xc0
[90444.108484]  ? do_filp_open+0xa5/0x100
[90444.109732]  ? handle_mm_fault+0x117b/0x1e00
[90444.110970]  ? __check_object_size+0x46/0x147
[90444.112205]  ? __check_object_size+0x136/0x147
[90444.113402]  __sys_sendmsg+0x59/0xa0
[90444.114587]  do_syscall_64+0x4d/0x90
[90444.115782]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
[90444.116953] RIP: 0033:0x7f3c2393b7b8
[90444.118101] Code: Bad RIP value.
[90444.119240] RSP: 002b:00007ffc6ad8e6c8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
[90444.120408] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f3c2393b7b8
[90444.121583] RDX: 0000000000000000 RSI: 00007ffc6ad8e740 RDI: 0000000000000003
[90444.122750] RBP: 000000005eea0c3a R08: 0000000000000001 R09: 00007ffc6ad8e68c
[90444.123928] R10: 0000000000404fa8 R11: 0000000000000246 R12: 0000000000000001
[90444.125073] R13: 0000000000000000 R14: 00007ffc6ad92a00 R15: 00000000004866a0
[90444.126221] Modules linked in: act_skbedit act_tunnel_key act_mirred bonding vxlan ip6_udp_tunnel udp_tunnel nfnetlink act_gact cls_flower sch_ingress openvswitch nsh nf_conncount nfsv3 nfs_acl nfs lockd grace fscache tun bridge stp llc sunrpc rdma_ucm rdma_cm iw_cm ib_cm mlx5_ib ib_uverbs ib_core mlx5_core intel_r
apl_msr intel_rapl_common sb_edac x86_pkg_temp_thermal intel_powerclamp coretemp kvm_intel mlxfw kvm act_ct nf_flow_table nf_nat nf_conntrack irqbypass crct10dif_pclmul nf_defrag_ipv6 igb ipmi_ssif libcrc32c crc32_pclmul crc32c_intel ipmi_si nf_defrag_ipv4 ptp ghash_clmulni_intel mei_me ses iTCO_wdt i2c_i801 pps_core
ioatdma iTCO_vendor_support joydev mei enclosure intel_cstate i2c_smbus wmi dca ipmi_devintf intel_uncore lpc_ich ipmi_msghandler pcspkr acpi_pad acpi_power_meter ast i2c_algo_bit drm_vram_helper drm_kms_helper drm_ttm_helper ttm drm mpt3sas raid_class scsi_transport_sas
[90444.136253] CR2: 0000000000000000
[90444.137621] ---[ end trace 924af62aa2b151bd ]---

Fixes: 553f9328 ("net/mlx5e: Support tc block sharing for representors")
Reported-by: David Ahern <dsahern@gmail.com>
Signed-off-by: Vlad Buslov <vladbu@mellanox.com>
Reviewed-by: Roi Dayan <roid@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>

Refactoring eswitch ingress acl codes accidentally inserts extra
memset zero that removes vlan and/or qos setting in legacy mode.

Fixes: 07bab950 ("net/mlx5: E-Switch, Refactor eswitch ingress acl codes")
Signed-off-by: Vu Pham <vuhuong@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>

Fix eeprom SFP query support by setting i2c_addr, offset and page number
correctly. Unlike QSFP modules, SFP eeprom params are as follow:
- i2c_addr is 0x50 for offset 0 - 255 and 0x51 for offset 256 - 511.
- Page number is always zero.
- Page offset is always relative to zero.

As part of eeprom query, query the module ID (SFP / QSFP*) via helper
function to set the params accordingly.

In addition, change mlx5_qsfp_eeprom_page() input type to be u16 to avoid
unnecessary casting.

Fixes: a708fb7b ("net/mlx5e: ethtool, Add support for EEPROM high pages query")
Signed-off-by: Eran Ben Elisha <eranbe@mellanox.com>
Signed-off-by: Huy Nguyen <huyn@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>

In order for no_refcnt and is_data to be the lowest order two
bits in the 'val' we have to pad out the bitfield of the u8.

Fixes: ad0f75e5 ("cgroup: fix cgroup_sk_alloc() for sk_clone_lock()")
Reported-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

Fix sockmap tests which rely on old bpf_prog_dispatch behaviour.
In the first case, the tests check that detaching without giving
a program succeeds. Since these are not the desired semantics,
invert the condition. In the second case, the clean up code doesn't
supply the necessary program fds.

Fixes: bb0de313 ("bpf: sockmap: Require attach_bpf_fd when detaching a program")
Reported-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Lorenz Bauer <lmb@cloudflare.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Jakub Sitnicki <jakub@cloudflare.com>
Link: https://lore.kernel.org/bpf/20200709115151.75829-1-lmb@cloudflare.com

syzkaller found its way into setsockopt with TCP_CONGESTION "cdg".
tcp_cdg_init() does a kcalloc to store the gradients. As sk_clone_lock
just copies all the memory, the allocated pointer will be copied as
well, if the app called setsockopt(..., TCP_CONGESTION) on the listener.
If now the socket will be destroyed before the congestion-control
has properly been initialized (through a call to tcp_init_transfer), we
will end up freeing memory that does not belong to that particular
socket, opening the door to a double-free:

[   11.413102] ==================================================================
[   11.414181] BUG: KASAN: double-free or invalid-free in tcp_cleanup_congestion_control+0x58/0xd0
[   11.415329]
[   11.415560] CPU: 3 PID: 4884 Comm: syz-executor.5 Not tainted 5.8.0-rc2 #80
[   11.416544] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.1-0-ga5cab58e9a3f-prebuilt.qemu.org 04/01/2014
[   11.418148] Call Trace:
[   11.418534]  <IRQ>
[   11.418834]  dump_stack+0x7d/0xb0
[   11.419297]  print_address_description.constprop.0+0x1a/0x210
[   11.422079]  kasan_report_invalid_free+0x51/0x80
[   11.423433]  __kasan_slab_free+0x15e/0x170
[   11.424761]  kfree+0x8c/0x230
[   11.425157]  tcp_cleanup_congestion_control+0x58/0xd0
[   11.425872]  tcp_v4_destroy_sock+0x57/0x5a0
[   11.426493]  inet_csk_destroy_sock+0x153/0x2c0
[   11.427093]  tcp_v4_syn_recv_sock+0xb29/0x1100
[   11.427731]  tcp_get_cookie_sock+0xc3/0x4a0
[   11.429457]  cookie_v4_check+0x13d0/0x2500
[   11.433189]  tcp_v4_do_rcv+0x60e/0x780
[   11.433727]  tcp_v4_rcv+0x2869/0x2e10
[   11.437143]  ip_protocol_deliver_rcu+0x23/0x190
[   11.437810]  ip_local_deliver+0x294/0x350
[   11.439566]  __netif_receive_skb_one_core+0x15d/0x1a0
[   11.441995]  process_backlog+0x1b1/0x6b0
[   11.443148]  net_rx_action+0x37e/0xc40
[   11.445361]  __do_softirq+0x18c/0x61a
[   11.445881]  asm_call_on_stack+0x12/0x20
[   11.446409]  </IRQ>
[   11.446716]  do_softirq_own_stack+0x34/0x40
[   11.447259]  do_softirq.part.0+0x26/0x30
[   11.447827]  __local_bh_enable_ip+0x46/0x50
[   11.448406]  ip_finish_output2+0x60f/0x1bc0
[   11.450109]  __ip_queue_xmit+0x71c/0x1b60
[   11.451861]  __tcp_transmit_skb+0x1727/0x3bb0
[   11.453789]  tcp_rcv_state_process+0x3070/0x4d3a
[   11.456810]  tcp_v4_do_rcv+0x2ad/0x780
[   11.457995]  __release_sock+0x14b/0x2c0
[   11.458529]  release_sock+0x4a/0x170
[   11.459005]  __inet_stream_connect+0x467/0xc80
[   11.461435]  inet_stream_connect+0x4e/0xa0
[   11.462043]  __sys_connect+0x204/0x270
[   11.465515]  __x64_sys_connect+0x6a/0xb0
[   11.466088]  do_syscall_64+0x3e/0x70
[   11.466617]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
[   11.467341] RIP: 0033:0x7f56046dc469
[   11.467844] Code: Bad RIP value.
[   11.468282] RSP: 002b:00007f5604dccdd8 EFLAGS: 00000246 ORIG_RAX: 000000000000002a
[   11.469326] RAX: ffffffffffffffda RBX: 000000000068bf00 RCX: 00007f56046dc469
[   11.470379] RDX: 0000000000000010 RSI: 0000000020000000 RDI: 0000000000000004
[   11.471311] RBP: 00000000ffffffff R08: 0000000000000000 R09: 0000000000000000
[   11.472286] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
[   11.473341] R13: 000000000041427c R14: 00007f5604dcd5c0 R15: 0000000000000003
[   11.474321]
[   11.474527] Allocated by task 4884:
[   11.475031]  save_stack+0x1b/0x40
[   11.475548]  __kasan_kmalloc.constprop.0+0xc2/0xd0
[   11.476182]  tcp_cdg_init+0xf0/0x150
[   11.476744]  tcp_init_congestion_control+0x9b/0x3a0
[   11.477435]  tcp_set_congestion_control+0x270/0x32f
[   11.478088]  do_tcp_setsockopt.isra.0+0x521/0x1a00
[   11.478744]  __sys_setsockopt+0xff/0x1e0
[   11.479259]  __x64_sys_setsockopt+0xb5/0x150
[   11.479895]  do_syscall_64+0x3e/0x70
[   11.480395]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
[   11.481097]
[   11.481321] Freed by task 4872:
[   11.481783]  save_stack+0x1b/0x40
[   11.482230]  __kasan_slab_free+0x12c/0x170
[   11.482839]  kfree+0x8c/0x230
[   11.483240]  tcp_cleanup_congestion_control+0x58/0xd0
[   11.483948]  tcp_v4_destroy_sock+0x57/0x5a0
[   11.484502]  inet_csk_destroy_sock+0x153/0x2c0
[   11.485144]  tcp_close+0x932/0xfe0
[   11.485642]  inet_release+0xc1/0x1c0
[   11.486131]  __sock_release+0xc0/0x270
[   11.486697]  sock_close+0xc/0x10
[   11.487145]  __fput+0x277/0x780
[   11.487632]  task_work_run+0xeb/0x180
[   11.488118]  __prepare_exit_to_usermode+0x15a/0x160
[   11.488834]  do_syscall_64+0x4a/0x70
[   11.489326]  entry_SYSCALL_64_after_hwframe+0x44/0xa9

Wei Wang fixed a part of these CDG-malloc issues with commit c1201444
("tcp: memset ca_priv data to 0 properly").

This patch here fixes the listener-scenario: We make sure that listeners
setting the congestion-control through setsockopt won't initialize it
(thus CDG never allocates on listeners). For those who use AF_UNSPEC to
reuse a socket, tcp_disconnect() is changed to cleanup afterwards.

(The issue can be reproduced at least down to v4.4.x.)

Cc: Wei Wang <weiwan@google.com>
Cc: Eric Dumazet <edumazet@google.com>
Fixes: 2b0a8c9e ("tcp: add CDG congestion control")
Signed-off-by: Christoph Paasch <cpaasch@apple.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

bpf_sk_reuseport_detach is currently called when sk->sk_user_data
is not NULL.  It is incorrect because sk->sk_user_data may not be
managed by the bpf's reuseport_array.  It has been reported in [1] that,
the bpf_sk_reuseport_detach() which is called from udp_lib_unhash() has
corrupted the sk_user_data managed by l2tp.

This patch solves it by using another bit (defined as SK_USER_DATA_BPF)
of the sk_user_data pointer value.  It marks that a sk_user_data is
managed/owned by BPF.

The patch depends on a PTRMASK introduced in
commit f1ff5ce2 ("net, sk_msg: Clear sk_user_data pointer on clone if tagged").

[ Note: sk->sk_user_data is used by bpf's reuseport_array only when a sk is
  added to the bpf's reuseport_array.
  i.e. doing setsockopt(SO_REUSEPORT) and having "sk->sk_reuseport == 1"
  alone will not stop sk->sk_user_data being used by other means. ]

[1]: https://lore.kernel.org/netdev/20200706121259.GA20199@katalix.com/

Fixes: 5dc4c4b7 ("bpf: Introduce BPF_MAP_TYPE_REUSEPORT_SOCKARRAY")
Reported-by: James Chapman <jchapman@katalix.com>
Reported-by: syzbot+9f092552ba9a5efca5df@syzkaller.appspotmail.com
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: James Chapman <jchapman@katalix.com>
Acked-by: James Chapman <jchapman@katalix.com>
Link: https://lore.kernel.org/bpf/20200709061110.4019316-1-kafai@fb.com

It makes little sense for copying sk_user_data of reuseport_array during
sk_clone_lock().  This patch reuses the SK_USER_DATA_NOCOPY bit introduced in
commit f1ff5ce2 ("net, sk_msg: Clear sk_user_data pointer on clone if tagged").
It is used to mark the sk_user_data is not supposed to be copied to its clone.

Although the cloned sk's sk_user_data will not be used/freed in
bpf_sk_reuseport_detach(), this change can still allow the cloned
sk's sk_user_data to be used by some other means.

Freeing the reuseport_array's sk_user_data does not require a rcu grace
period.  Thus, the existing rcu_assign_sk_user_data_nocopy() is not
used.

Fixes: 5dc4c4b7 ("bpf: Introduce BPF_MAP_TYPE_REUSEPORT_SOCKARRAY")
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Jakub Sitnicki <jakub@cloudflare.com>
Link: https://lore.kernel.org/bpf/20200709061104.4018798-1-kafai@fb.com

If the genlmsg_put() call in ethnl_default_dumpit() fails, we bail out
without checking if we already have some messages in current skb like we do
with ethnl_default_dump_one() failure later. Therefore if existing messages
almost fill up the buffer so that there is not enough space even for
netlink and genetlink header, we lose all prepared messages and return and
error.

Rather than duplicating the skb->len check, move the genlmsg_put(),
genlmsg_cancel() and genlmsg_end() calls into ethnl_default_dump_one().
This is also more logical as all message composition will be in
ethnl_default_dump_one() and only iteration logic will be left in
ethnl_default_dumpit().

Fixes: 728480f1 ("ethtool: default handlers for GET requests")
Reported-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Michal Kubecek <mkubecek@suse.cz>
Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

When tcf_block_get() fails inside atm_tc_init(),
atm_tc_put() is called to release the qdisc p->link.q.
But the flow->ref prevents it to do so, as the flow->ref
is still zero.

Fix this by moving the p->link.ref initialization before
tcf_block_get().

Fixes: 6529eaba ("net: sched: introduce tcf block infractructure")
Reported-and-tested-by: syzbot+d411cff6ab29cc2c311b@syzkaller.appspotmail.com
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

NVM config file address will be modified when the MBI image is upgraded.
Driver would return stale config values if user reads the nvm-config
(via ethtool -d) in this state. The fix is to re-populate nvm attribute
info while reading the nvm config values/partition.

Changes from previous version:
-------------------------------
v3: Corrected the formatting in 'Fixes' tag.
v2: Added 'Fixes' tag.

Fixes: 1ac4329a ("qed: Add configuration information to register dump and debug data")
Signed-off-by: Sudarsana Reddy Kalluru <skalluru@marvell.com>
Signed-off-by: Igor Russkikh <irusskikh@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Convert all-mask IP address to Big Endian, instead, for comparison.

Fixes: f286dd8e ("cxgb4: use correct type for all-mask IP address comparison")
Signed-off-by: Rahul Lakkireddy <rahul.lakkireddy@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

A scenario has been observed where a 'bc_init' message for a link is not
retransmitted if it fails to be received by the peer. This leads to the
peer never establishing the link fully and it discarding all other data
received on the link. In this scenario the message is lost in transit to
the peer.

The issue is traced to the 'nxt_retr' field of the skb not being
initialised for links that aren't a bc_sndlink. This leads to the
comparison in tipc_link_advance_transmq() that gates whether to attempt
retransmission of a message performing in an undesirable way.
Depending on the relative value of 'jiffies', this comparison:
    time_before(jiffies, TIPC_SKB_CB(skb)->nxt_retr)
may return true or false given that 'nxt_retr' remains at the
uninitialised value of 0 for non bc_sndlinks.

This is most noticeable shortly after boot when jiffies is initialised
to a high value (to flush out rollover bugs) and we compare a jiffies of,
say, 4294940189 to zero. In that case time_before returns 'true' leading
to the skb not being retransmitted.

The fix is to ensure that all skbs have a valid 'nxt_retr' time set for
them and this is achieved by refactoring the setting of this value into
a central function.
With this fix, transmission losses of 'bc_init' messages do not stall
the link establishment forever because the 'bc_init' message is
retransmitted and the link eventually establishes correctly.

Fixes: 382f598f ("tipc: reduce duplicate packets for unicast traffic")
Acked-by: Jon Maloy <jmaloy@redhat.com>
Signed-off-by: Hamish Martin <hamish.martin@alliedtelesis.co.nz>
Signed-off-by: David S. Miller <davem@davemloft.net>

In the tx path of l2tp, l2tp_xmit_skb() calls skb_dst_set() to set
skb's dst. However, it will eventually call inet6_csk_xmit() or
ip_queue_xmit() where skb's dst will be overwritten by:

   skb_dst_set_noref(skb, dst);

without releasing the old dst in skb. Then it causes dst/dev refcnt leak:

  unregister_netdevice: waiting for eth0 to become free. Usage count = 1

This can be reproduced by simply running:

  # modprobe l2tp_eth && modprobe l2tp_ip
  # sh ./tools/testing/selftests/net/l2tp.sh

So before going to inet6_csk_xmit() or ip_queue_xmit(), skb's dst
should be dropped. This patch is to fix it by removing skb_dst_set()
from l2tp_xmit_skb() and moving skb_dst_drop() into l2tp_xmit_core().

Fixes: 3557baab ("[L2TP]: PPP over L2TP driver core")
Reported-by: Hangbin Liu <liuhangbin@gmail.com>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: James Chapman <jchapman@katalix.com>
Tested-by: James Chapman <jchapman@katalix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Karsten Graul says:

====================
net/smc: fixes 2020-07-08

Please apply the following patch series for smc to netdev's net tree.

The patches fix problems found during more testing of SMC
functionality, resulting in hang conditions and unneeded link
deactivations. The clc module was hardened to be prepared for
possible future SMCD versions.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

CLC proposal messages of future SMCD versions could be larger than SMCD
V1 CLC proposal messages.
To enable toleration in SMC V1 the receival of CLC proposal messages
is adapted:
* accept larger length values in CLC proposal
* check trailing eye catcher for incoming CLC proposal with V1 length only
* receive the whole CLC proposal even in cases it does not fit into the
  V1 buffer

Fixes: e7b7a64a ("smc: support variable CLC proposal messages")
Signed-off-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The similar smc_ib_devices spinlock has been converted to a mutex.
Protecting the smcd_dev_list by a mutex is possible as well. This
patch converts the smcd_dev_list spinlock to a mutex.

Fixes: c6ba7c9b ("net/smc: add base infrastructure for SMC-D and ISM")
Signed-off-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Tests showed this BUG:
[572555.252867] BUG: sleeping function called from invalid context at kernel/locking/mutex.c:935
[572555.252876] in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 131031, name: smcapp
[572555.252879] INFO: lockdep is turned off.
[572555.252883] CPU: 1 PID: 131031 Comm: smcapp Tainted: G           O      5.7.0-rc3uschi+ #356
[572555.252885] Hardware name: IBM 3906 M03 703 (LPAR)
[572555.252887] Call Trace:
[572555.252896]  [<00000000ac364554>] show_stack+0x94/0xe8
[572555.252901]  [<00000000aca1f400>] dump_stack+0xa0/0xe0
[572555.252906]  [<00000000ac3c8c10>] ___might_sleep+0x260/0x280
[572555.252910]  [<00000000acdc0c98>] __mutex_lock+0x48/0x940
[572555.252912]  [<00000000acdc15c2>] mutex_lock_nested+0x32/0x40
[572555.252975]  [<000003ff801762d0>] mlx5_lag_get_roce_netdev+0x30/0xc0 [mlx5_core]
[572555.252996]  [<000003ff801fb3aa>] mlx5_ib_get_netdev+0x3a/0xe0 [mlx5_ib]
[572555.253007]  [<000003ff80063848>] smc_pnet_find_roce_resource+0x1d8/0x310 [smc]
[572555.253011]  [<000003ff800602f0>] __smc_connect+0x1f0/0x3e0 [smc]
[572555.253015]  [<000003ff80060634>] smc_connect+0x154/0x190 [smc]
[572555.253022]  [<00000000acbed8d4>] __sys_connect+0x94/0xd0
[572555.253025]  [<00000000acbef620>] __s390x_sys_socketcall+0x170/0x360
[572555.253028]  [<00000000acdc6800>] system_call+0x298/0x2b8
[572555.253030] INFO: lockdep is turned off.

Function smc_pnet_find_rdma_dev() might be called from
smc_pnet_find_roce_resource(). It holds the smc_ib_devices list
spinlock while calling infiniband op get_netdev(). At least for mlx5
the get_netdev operation wants mutex serialization, which conflicts
with the smc_ib_devices spinlock.
This patch switches the smc_ib_devices spinlock into a mutex to
allow sleeping when calling get_netdev().

Fixes: a4cf0443 ("smc: introduce SMC as an IB-client")
Signed-off-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Wait for pending sends only when smc_switch_conns() found a link to move
the connections to. Do not wait during link freeing, this can lead to
permanent hang situations. And refuse to provide a new tx slot on an
unusable link.

Fixes: c6f02ebe ("net/smc: switch connections to alternate link")
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

There might be races in scenarios where both SMC link groups are on the
same system. Prevent that by creating separate wait queues for LLC flows
and messages. Switch to non-interruptable versions of wait_event() and
wake_up() for the llc flow waiter to make sure the waiters get control
sequentially. Fine tune the llc_flow_lock to include the assignment of
the message. Write to system log when an unexpected message was
dropped. And remove an extra indirection and use the existing local
variable lgr in smc_llc_enqueue().

Fixes: 555da9af ("net/smc: add event-based llc_flow framework")
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

This patch fixes ip dst and ipv6 address filters.
There were 2 mistakes in the code, which led to the issue:
* invalid register was used for ipv4 dst address;
* incorrect write order of dwords for ipv6 addresses.

Fixes: 23e7a718 ("net: aquantia: add rx-flow filter definitions")
Signed-off-by: Dmitry Bogdanov <dbogdanov@marvell.com>
Signed-off-by: Mark Starovoytov <mstarovoitov@marvell.com>
Signed-off-by: Alexander Lobakin <alobakin@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The queue reset pattern is used in a couple different places,
only slightly different from each other, and could cause
issues if one gets changed and the other didn't.  This puts
them together so that only one version is needed, yet each
can have slighty different effects by passing in a pointer
to a work function to do whatever configuration twiddling is
needed in the middle of the reset.

This specifically addresses issues seen where under loops
of changing ring size or queue count parameters we could
occasionally bump into the netdev watchdog.

v2: added more commit message commentary

Fixes: 4d03e00a ("ionic: Add initial ethtool support")
Signed-off-by: Shannon Nelson <snelson@pensando.io>
Acked-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

Toshiaki pointed out that we now have two very similar functions to extract
the L3 protocol number in the presence of VLAN tags. And Daniel pointed out
that the unbounded parsing loop makes it possible for maliciously crafted
packets to loop through potentially hundreds of tags.

Fix both of these issues by consolidating the two parsing functions and
limiting the VLAN tag parsing to a max depth of 8 tags. As part of this,
switch over __vlan_get_protocol() to use skb_header_pointer() instead of
pskb_may_pull(), to avoid the possible side effects of the latter and keep
the skb pointer 'const' through all the parsing functions.

v2:
- Use limit of 8 tags instead of 32 (matching XMIT_RECURSION_LIMIT)
Reported-by: Toshiaki Makita <toshiaki.makita1@gmail.com>
Reported-by: Daniel Borkmann <daniel@iogearbox.net>
Fixes: d7bf2ebe ("sched: consistently handle layer3 header accesses in the presence of VLANs")
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>