The len used for skb_put_padto is wrong, it need to add len of hdr.

In qrtr_node_enqueue, local variable size_t len is assign with
skb->len, then skb_push(skb, sizeof(*hdr)) will add skb->len with
sizeof(*hdr), so local variable size_t len is not same with skb->len
after skb_push(skb, sizeof(*hdr)).

Then the purpose of skb_put_padto(skb, ALIGN(len, 4)) is to add add
pad to the end of the skb's data if skb->len is not aligned to 4, but
unfortunately it use len instead of skb->len, at this line, skb->len
is 32 bytes(sizeof(*hdr)) more than len, for example, len is 3 bytes,
then skb->len is 35 bytes(3 + 32), and ALIGN(len, 4) is 4 bytes, so
__skb_put_padto will do nothing after check size(35) < len(4), the
correct value should be 36(sizeof(*hdr) + ALIGN(len, 4) = 32 + 4),
then __skb_put_padto will pass check size(35) < len(36) and add 1 byte
to the end of skb's data, then logic is correct.

function of skb_push:
void *skb_push(struct sk_buff *skb, unsigned int len)
{
	skb->data -= len;
	skb->len  += len;
	if (unlikely(skb->data < skb->head))
		skb_under_panic(skb, len, __builtin_return_address(0));
	return skb->data;
}

function of skb_put_padto
static inline int skb_put_padto(struct sk_buff *skb, unsigned int len)
{
	return __skb_put_padto(skb, len, true);
}

function of __skb_put_padto
static inline int __skb_put_padto(struct sk_buff *skb, unsigned int len,
				  bool free_on_error)
{
	unsigned int size = skb->len;

	if (unlikely(size < len)) {
		len -= size;
		if (__skb_pad(skb, len, free_on_error))
			return -ENOMEM;
		__skb_put(skb, len);
	}
	return 0;
}
Signed-off-by: Carl Huang <cjhuang@codeaurora.org>
Signed-off-by: Wen Gong <wgong@codeaurora.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

Atomic operations that span cache lines are super-expensive on x86
(not just to the current processor, but also to other processes as all
memory operations are blocked until the operation completes). Upcoming
x86 processors have a switch to cause such operations to generate a #AC
trap. It is expected that some real time systems will enable this mode
in BIOS.

In preparation for this, it is necessary to fix code that may execute
atomic instructions with operands that cross cachelines because the #AC
trap will crash the kernel.

Since "pwol_mask" is local and never exposed to concurrency, there is
no need to set bits in pwol_mask using atomic operations.

Directly operate on the byte which contains the bit instead of using
__set_bit() to avoid any big endian concern due to type cast to
unsigned long in __set_bit().
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Current code use dma_wmb() to ensure Rx/Tx descriptors are visible
to device before writing to doorbell.

However, these dma_wmb() are wrong and unnecessary. Therefore,
they should be removed.

iowrite32be() called from gve_rx_write_doorbell()/gve_tx_put_doorbell()
should guaratee that all previous writes to WB/UC memory is visible to
device before the write done by iowrite32be().

E.g. On ARM64, iowrite32be() calls __iowmb() which expands to dma_wmb()
and only then calls __raw_writel().
Reviewed-by: Si-Wei Liu <si-wei.liu@oracle.com>
Signed-off-by: Liran Alon <liran.alon@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The kernel test robot reports a boot failure with qemu in 5.5-rc,
referencing commit 2203cbf2 ("net: sfp: move fwnode parsing into
sfp-bus layer"). This is caused by phylink_create() being passed a
NULL fwnode, causing fwnode_property_get_reference_args() to return
-EINVAL.

Don't attempt to attach to a SFP bus if we have no fwnode, which
avoids this issue.
Reported-by: kernel test robot <rong.a.chen@intel.com>
Fixes: 2203cbf2 ("net: sfp: move fwnode parsing into sfp-bus layer")
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

DaveM's git tree have been moved into a named subdir 'netdev' to deal with
allowing Jakub Kicinski to help co-maintain the trees.

Link: https://www.kernel.org/doc/html/latest/networking/netdev-FAQ.htmlSigned-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The loopback feature is only supported on a few drivers like broadcom,
mellanox, etc. The default veth driver has not supported it yet. To avoid
returning failed and making the runner feel confused, let's just skip
the test on drivers that not support loopback.

Fixes: ad113409 ("selftests: Add loopback test")
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Reviewed-by: Simon Horman <simon.horman@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>

Merge tag 'linux-can-fixes-for-5.5-20200102' of git://git.kernel.org/pub/scm/linux/kernel/git/mkl/linux-can

Marc Kleine-Budde says:

====================
pull-request: can 2020-01-02

this is a pull request of 9 patches for net/master.

The first 5 patches target all the tcan4x5x driver. The first 3 patches
of them are by Dan Murphy and Sean Nyekjaer and improve the device
initialization (power on, reset and get device out of standby before
register access). The next patch is by Dan Murphy and disables the INH
pin device-state if the GPIO is unavailable. The last patch for the
tcan4x5x driver is by Gustavo A. R. Silva and fixes an inconsistent
PTR_ERR check in the tcan4x5x_parse_config() function.

The next patch is by Oliver Hartkopp and targets the generic CAN device
infrastructure. It ensures that an initialized headroom in outgoing CAN
sk_buffs (e.g. if injected by AF_PACKET).

The last 2 patches are by Johan Hovold and fix the kvaser_usb and gs_usb
drivers by always using the current alternate setting not blindly the
first one.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

In order to dump the FECs registers the clocks have to be ticking,
otherwise a data abort occurs.  Add calls to runtime PM so they are
enabled and later disabled.

Fixes: e8fcfcd5 ("net: fec: optimize the clock management to save power")
Reported-by: Chris Healy <Chris.Healy@zii.aero>
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

Before ip_tunnel_ecn_encap() and udp_tunnel_xmit_skb() we should filter
tos value by RT_TOS() instead of using config tos directly.

vxlan_get_route() would filter the tos to fl4.flowi4_tos but we didn't
return it back, as geneve_get_v4_rt() did. So we have to use RT_TOS()
directly in function ip_tunnel_ecn_encap().

Fixes: 206aaafc ("VXLAN: Use IP Tunnels tunnel ENC encap API")
Fixes: 1400615d ("vxlan: allow setting ipv6 traffic class")
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The variables 'window_interval' is u64 and do_div()
truncates it to 32 bits, which means it can test
non-zero and be truncated to zero for division.
The unit of window_interval is nanoseconds,
so its lower 32-bit is relatively easy to exceed.
Fix this issue by using div64_u64() instead.

Fixes: 7298de9c ("sch_cake: Add ingress mode")
Signed-off-by: Wen Yang <wenyang@linux.alibaba.com>
Cc: Kevin Darbyshire-Bryant <ldir@darbyshire-bryant.me.uk>
Cc: Toke Høiland-Jørgensen <toke@redhat.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Cong Wang <xiyou.wangcong@gmail.com>
Cc: cake@lists.bufferbloat.net
Cc: netdev@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Acked-by: Toke Høiland-Jørgensen <toke@toke.dk>
Signed-off-by: David S. Miller <davem@davemloft.net>

It can take on the values of '0', '1', and '2' and thus
is not a boolean.
Signed-off-by: David S. Miller <davem@davemloft.net>

When we receive a D-SACK, where the sequence number satisfies:
	undo_marker <= start_seq < end_seq <= prior_snd_una
we consider this is a valid D-SACK and tcp_is_sackblock_valid()
returns true, then this D-SACK is discarded as "old stuff",
but the variable first_sack_index is not marked as negative
in tcp_sacktag_write_queue().

If this D-SACK also carries a SACK that needs to be processed
(for example, the previous SACK segment was lost), this SACK
will be treated as a D-SACK in the following processing of
tcp_sacktag_write_queue(), which will eventually lead to
incorrect updates of undo_retrans and reordering.

Fixes: fd6dad61 ("[TCP]: Earlier SACK block verification & simplify access to them")
Signed-off-by: Pengcheng Yang <yangpc@wangsu.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

mv88e6xxx_port_set_cmode() relies on cmode stored in struct
mv88e6xxx_port to skip cmode update when the requested value matches the
cached value. It turns out that mv88e6xxx_port_hidden_write() might
change the port cmode setting as a side effect, so we can't rely on the
cached value to determine that cmode update in not necessary.

Force cmode update in mv88e6341_port_set_cmode(), to make
serdes configuration work again. Other mv88e6xxx_port_set_cmode()
callers keep the current behaviour.

This fixes serdes configuration of the 6141 switch on SolidRun Clearfog
GT-8K.

Fixes: 7a3007d2 ("net: dsa: mv88e6xxx: fully support SERDES on Topaz family")
Reported-by: Denis Odintsov <d.odintsov@traviangames.com>
Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

Under load, the RX side of the mscan driver can get stuck while TX still
works. Restarting the interface locks up the system. This behaviour
could be reproduced reliably on a MPC5121e based system.

The patch fixes the return value of the NAPI polling function (should be
the number of processed packets, not constant 1) and the condition under
which IRQs are enabled again after polling is finished.

With this patch, no more lockups were observed over a test period of ten
days.

Fixes: afa17a50 ("net/can: add driver for mscan family & mpc52xx_mscan")
Signed-off-by: Florian Faber <faber@faberman.de>
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

Make sure to always use the descriptors of the current alternate setting
to avoid future issues when accessing fields that may differ between
settings.
Signed-off-by: Johan Hovold <johan@kernel.org>
Fixes: d08e973a ("can: gs_usb: Added support for the GS_USB CAN devices")
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

Make sure to use the current alternate setting when verifying the
interface descriptors to avoid binding to an invalid interface.

Failing to do so could cause the driver to misbehave or trigger a WARN()
in usb_submit_urb() that kernels with panic_on_warn set would choke on.

Fixes: aec5fb22 ("can: kvaser_usb: Add support for Kvaser USB hydra family")
Cc: stable <stable@vger.kernel.org>     # 4.19
Cc: Jimmy Assarsson <extja@kvaser.com>
Cc: Christer Beskow <chbe@kvaser.com>
Cc: Nicklas Johansson <extnj@kvaser.com>
Cc: Martin Henriksson <mh@kvaser.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

KMSAN sysbot detected a read access to an untinitialized value in the
headroom of an outgoing CAN related sk_buff. When using CAN sockets this
area is filled appropriately - but when using a packet socket this
initialization is missing.

The problematic read access occurs in the CAN receive path which can
only be triggered when the sk_buff is sent through a (virtual) CAN
interface. So we check in the sending path whether we need to perform
the missing initializations.

Fixes: d3b58c47 ("can: replace timestamp as unique skb attribute")
Reported-by: syzbot+b02ff0707a97e4e79ebb@syzkaller.appspotmail.com
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Tested-by: Oliver Hartkopp <socketcan@hartkopp.net>
Cc: linux-stable <stable@vger.kernel.org> # >= v4.1
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

Fix inconsistent IS_ERR and PTR_ERR in tcan4x5x_parse_config().

The proper pointer to be passed as argument is tcan4x5x->device_wake_gpio.

This bug was detected with the help of Coccinelle.

Fixes: 2de49735 ("can: tcan45x: Make wake-up GPIO an optional GPIO")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Acked-by: Dan Murphy <dmurphy@ti.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

If the device state GPIO is not connected to the host then disable the
INH output from the TCAN device per section 8.3.5 of the data sheet.
Signed-off-by: Dan Murphy <dmurphy@ti.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

It's a good idea to reset a ip-block/spi device before using it, this
patch will reset the device.

And a generic reset function if needed elsewhere.
Signed-off-by: Sean Nyekjaer <sean@geanix.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

The tcan4x5x_parse_config() function now performs action on the device
either reading or writing and a reset. If the devive has a switchable
power supppy (i.e. regulator is managed) it needs to be turned on.

So turn on the regulator if available. If the parsing fails, turn off
the regulator.

Fixes: 2de49735 ("can: tcan45x: Make wake-up GPIO an optional GPIO")
Signed-off-by: Dan Murphy <dmurphy@ti.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

The m_can tries to detect if Non ISO Operation is available while in
standby mode, this function results in the following error:

| tcan4x5x spi2.0 (unnamed net_device) (uninitialized): Failed to init module
| tcan4x5x spi2.0: m_can device registered (irq=84, version=32)
| tcan4x5x spi2.0 can2: TCAN4X5X successfully initialized.

When the tcan device comes out of reset it goes in standby mode. The
m_can driver tries to access the control register but fails due to the
device being in standby mode.

So this patch will put the tcan device in normal mode before the m_can
driver does the initialization.

Fixes: 5443c226 ("can: tcan4x5x: Add tcan4x5x driver to the kernel")
Cc: stable@vger.kernel.org
Signed-off-by: Sean Nyekjaer <sean@geanix.com>
Acked-by: Dan Murphy <dmurphy@ti.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

Pull networking fixes from David Miller:

 1) Fix big endian overflow in nf_flow_table, from Arnd Bergmann.

 2) Fix port selection on big endian in nft_tproxy, from Phil Sutter.

 3) Fix precision tracking for unbound scalars in bpf verifier, from
    Daniel Borkmann.

 4) Fix integer overflow in socket rcvbuf check in UDP, from Antonio
    Messina.

 5) Do not perform a neigh confirmation during a pmtu update over a
    tunnel, from Hangbin Liu.

 6) Fix DMA mapping leak in dpaa_eth driver, from Madalin Bucur.

 7) Various PTP fixes for sja1105 dsa driver, from Vladimir Oltean.

 8) Add missing to dummy definition of of_mdiobus_child_is_phy(), from
    Geert Uytterhoeven

* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (54 commits)
  hsr: fix slab-out-of-bounds Read in hsr_debugfs_rename()
  net/sched: add delete_empty() to filters and use it in cls_flower
  tcp: Fix highest_sack and highest_sack_seq
  ptp: fix the race between the release of ptp_clock and cdev
  net: dsa: sja1105: Reconcile the meaning of TPID and TPID2 for E/T and P/Q/R/S
  Documentation: net: dsa: sja1105: Remove text about taprio base-time limitation
  net: dsa: sja1105: Remove restriction of zero base-time for taprio offload
  net: dsa: sja1105: Really make the PTP command read-write
  net: dsa: sja1105: Take PTP egress timestamp by port, not mgmt slot
  cxgb4/cxgb4vf: fix flow control display for auto negotiation
  mlxsw: spectrum: Use dedicated policer for VRRP packets
  mlxsw: spectrum_router: Skip loopback RIFs during MAC validation
  net: stmmac: dwmac-meson8b: Fix the RGMII TX delay on Meson8b/8m2 SoCs
  net/sched: act_mirred: Pull mac prior redir to non mac_header_xmit device
  net_sched: sch_fq: properly set sk->sk_pacing_status
  bnx2x: Fix accounting of vlan resources among the PFs
  bnx2x: Use appropriate define for vlan credit
  of: mdio: Add missing inline to of_mdiobus_child_is_phy() dummy
  net: phy: aquantia: add suspend / resume ops for AQR105
  dpaa_eth: fix DMA mapping leak
  ...

Pull tomoyo fixes from Tetsuo Handa:
 "Two bug fixes:

   - Suppress RCU warning at list_for_each_entry_rcu()

   - Don't use fancy names on sockets"

* tag 'tomoyo-fixes-for-5.5' of git://git.osdn.net/gitroot/tomoyo/tomoyo-test1:
  tomoyo: Suppress RCU warning at list_for_each_entry_rcu().
  tomoyo: Don't use nifty names on sockets.

hsr slave interfaces don't have debugfs directory.
So, hsr_debugfs_rename() shouldn't be called when hsr slave interface name
is changed.

Test commands:
    ip link add dummy0 type dummy
    ip link add dummy1 type dummy
    ip link add hsr0 type hsr slave1 dummy0 slave2 dummy1
    ip link set dummy0 name ap

Splat looks like:
[21071.899367][T22666] ap: renamed from dummy0
[21071.914005][T22666] ==================================================================
[21071.919008][T22666] BUG: KASAN: slab-out-of-bounds in hsr_debugfs_rename+0xaa/0xb0 [hsr]
[21071.923640][T22666] Read of size 8 at addr ffff88805febcd98 by task ip/22666
[21071.926941][T22666]
[21071.927750][T22666] CPU: 0 PID: 22666 Comm: ip Not tainted 5.5.0-rc2+ #240
[21071.929919][T22666] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006
[21071.935094][T22666] Call Trace:
[21071.935867][T22666]  dump_stack+0x96/0xdb
[21071.936687][T22666]  ? hsr_debugfs_rename+0xaa/0xb0 [hsr]
[21071.937774][T22666]  print_address_description.constprop.5+0x1be/0x360
[21071.939019][T22666]  ? hsr_debugfs_rename+0xaa/0xb0 [hsr]
[21071.940081][T22666]  ? hsr_debugfs_rename+0xaa/0xb0 [hsr]
[21071.940949][T22666]  __kasan_report+0x12a/0x16f
[21071.941758][T22666]  ? hsr_debugfs_rename+0xaa/0xb0 [hsr]
[21071.942674][T22666]  kasan_report+0xe/0x20
[21071.943325][T22666]  hsr_debugfs_rename+0xaa/0xb0 [hsr]
[21071.944187][T22666]  hsr_netdev_notify+0x1fe/0x9b0 [hsr]
[21071.945052][T22666]  ? __module_text_address+0x13/0x140
[21071.945897][T22666]  notifier_call_chain+0x90/0x160
[21071.946743][T22666]  dev_change_name+0x419/0x840
[21071.947496][T22666]  ? __read_once_size_nocheck.constprop.6+0x10/0x10
[21071.948600][T22666]  ? netdev_adjacent_rename_links+0x280/0x280
[21071.949577][T22666]  ? __read_once_size_nocheck.constprop.6+0x10/0x10
[21071.950672][T22666]  ? lock_downgrade+0x6e0/0x6e0
[21071.951345][T22666]  ? do_setlink+0x811/0x2ef0
[21071.951991][T22666]  do_setlink+0x811/0x2ef0
[21071.952613][T22666]  ? is_bpf_text_address+0x81/0xe0
[ ... ]

Reported-by: syzbot+9328206518f08318a5fd@syzkaller.appspotmail.com
Fixes: 4c2d5e33 ("hsr: rename debugfs file when interface name is changed")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Revert "net/sched: cls_u32: fix refcount leak in the error path of
u32_change()", and fix the u32 refcount leak in a more generic way that
preserves the semantic of rule dumping.
On tc filters that don't support lockless insertion/removal, there is no
need to guard against concurrent insertion when a removal is in progress.
Therefore, for most of them we can avoid a full walk() when deleting, and
just decrease the refcount, like it was done on older Linux kernels.
This fixes situations where walk() was wrongly detecting a non-empty
filter, like it happened with cls_u32 in the error path of change(), thus
leading to failures in the following tdc selftests:

 6aa7: (filter, u32) Add/Replace u32 with source match and invalid indev
 6658: (filter, u32) Add/Replace u32 with custom hash table and invalid handle
 74c2: (filter, u32) Add/Replace u32 filter with invalid hash table id

On cls_flower, and on (future) lockless filters, this check is necessary:
move all the check_empty() logic in a callback so that each filter
can have its own implementation. For cls_flower, it's sufficient to check
if no IDRs have been allocated.

This reverts commit 275c44aa.

Changes since v1:
 - document the need for delete_empty() when TCF_PROTO_OPS_DOIT_UNLOCKED
   is used, thanks to Vlad Buslov
 - implement delete_empty() without doing fl_walk(), thanks to Vlad Buslov
 - squash revert and new fix in a single patch, to be nice with bisect
   tests that run tdc on u32 filter, thanks to Dave Miller

Fixes: 275c44aa ("net/sched: cls_u32: fix refcount leak in the error path of u32_change()")
Fixes: 6676d5e4 ("net: sched: set dedicated tcf_walker flag when tp is empty")
Suggested-by: Jamal Hadi Salim <jhs@mojatatu.com>
Suggested-by: Vlad Buslov <vladbu@mellanox.com>
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Reviewed-by: Vlad Buslov <vladbu@mellanox.com>
Tested-by: Jamal Hadi Salim <jhs@mojatatu.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

>From commit 50895b9d ("tcp: highest_sack fix"), the logic about
setting tp->highest_sack to the head of the send queue was removed.
Of course the logic is error prone, but it is logical. Before we
remove the pointer to the highest sack skb and use the seq instead,
we need to set tp->highest_sack to NULL when there is no skb after
the last sack, and then replace NULL with the real skb when new skb
inserted into the rtx queue, because the NULL means the highest sack
seq is tp->snd_nxt. If tp->highest_sack is NULL and new data sent,
the next ACK with sack option will increase tp->reordering unexpectedly.

This patch sets tp->highest_sack to the tail of the rtx queue if
it's NULL and new data is sent. The patch keeps the rule that the
highest_sack can only be maintained by sack processing, except for
this only case.

Fixes: 50895b9d ("tcp: highest_sack fix")
Signed-off-by: Cambda Zhu <cambda@linux.alibaba.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

In a case when a ptp chardev (like /dev/ptp0) is open but an underlying
device is removed, closing this file leads to a race. This reproduces
easily in a kvm virtual machine:

ts# cat openptp0.c
int main() { ... fp = fopen("/dev/ptp0", "r"); ... sleep(10); }
ts# uname -r
5.5.0-rc3-46cf053e
ts# cat /proc/cmdline
... slub_debug=FZP
ts# modprobe ptp_kvm
ts# ./openptp0 &
[1] 670
opened /dev/ptp0, sleeping 10s...
ts# rmmod ptp_kvm
ts# ls /dev/ptp*
ls: cannot access '/dev/ptp*': No such file or directory
ts# ...woken up
[   48.010809] general protection fault: 0000 [#1] SMP
[   48.012502] CPU: 6 PID: 658 Comm: openptp0 Not tainted 5.5.0-rc3-46cf053e #25
[   48.014624] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), ...
[   48.016270] RIP: 0010:module_put.part.0+0x7/0x80
[   48.017939] RSP: 0018:ffffb3850073be00 EFLAGS: 00010202
[   48.018339] RAX: 000000006b6b6b6b RBX: 6b6b6b6b6b6b6b6b RCX: ffff89a476c00ad0
[   48.018936] RDX: fffff65a08d3ea08 RSI: 0000000000000247 RDI: 6b6b6b6b6b6b6b6b
[   48.019470] ...                                              ^^^ a slub poison
[   48.023854] Call Trace:
[   48.024050]  __fput+0x21f/0x240
[   48.024288]  task_work_run+0x79/0x90
[   48.024555]  do_exit+0x2af/0xab0
[   48.024799]  ? vfs_write+0x16a/0x190
[   48.025082]  do_group_exit+0x35/0x90
[   48.025387]  __x64_sys_exit_group+0xf/0x10
[   48.025737]  do_syscall_64+0x3d/0x130
[   48.026056]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
[   48.026479] RIP: 0033:0x7f53b12082f6
[   48.026792] ...
[   48.030945] Modules linked in: ptp i6300esb watchdog [last unloaded: ptp_kvm]
[   48.045001] Fixing recursive fault but reboot is needed!

This happens in:

static void __fput(struct file *file)
{   ...
    if (file->f_op->release)
        file->f_op->release(inode, file); <<< cdev is kfree'd here
    if (unlikely(S_ISCHR(inode->i_mode) && inode->i_cdev != NULL &&
             !(mode & FMODE_PATH))) {
        cdev_put(inode->i_cdev); <<< cdev fields are accessed here

Namely:

__fput()
  posix_clock_release()
    kref_put(&clk->kref, delete_clock) <<< the last reference
      delete_clock()
        delete_ptp_clock()
          kfree(ptp) <<< cdev is embedded in ptp
  cdev_put
    module_put(p->owner) <<< *p is kfree'd, bang!

Here cdev is embedded in posix_clock which is embedded in ptp_clock.
The race happens because ptp_clock's lifetime is controlled by two
refcounts: kref and cdev.kobj in posix_clock. This is wrong.

Make ptp_clock's sysfs device a parent of cdev with cdev_device_add()
created especially for such cases. This way the parent device with its
ptp_clock is not released until all references to the cdev are released.
This adds a requirement that an initialized but not exposed struct
device should be provided to posix_clock_register() by a caller instead
of a simple dev_t.

This approach was adopted from the commit 72139dfa ("watchdog: Fix
the race between the release of watchdog_core_data and cdev"). See
details of the implementation in the commit 233ed09d ("chardev: add
helper function to register char devs with a struct device").

Link: https://lore.kernel.org/linux-fsdevel/20191125125342.6189-1-vdronov@redhat.com/T/#uAnalyzed-by: Stephen Johnston <sjohnsto@redhat.com>
Analyzed-by: Vern Lovejoy <vlovejoy@redhat.com>
Signed-off-by: Vladis Dronov <vdronov@redhat.com>
Acked-by: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

For first-generation switches (SJA1105E and SJA1105T):
- TPID means C-Tag (typically 0x8100)
- TPID2 means S-Tag (typically 0x88A8)

While for the second generation switches (SJA1105P, SJA1105Q, SJA1105R,
SJA1105S) it is the other way around:
- TPID means S-Tag (typically 0x88A8)
- TPID2 means C-Tag (typically 0x8100)

In other words, E/T tags untagged traffic with TPID, and P/Q/R/S with
TPID2.

So the patch mentioned below fixed VLAN filtering for P/Q/R/S, but broke
it for E/T.

We strive for a common code path for all switches in the family, so just
lie in the static config packing functions that TPID and TPID2 are at
swapped bit offsets than they actually are, for P/Q/R/S. This will make
both switches understand TPID to be ETH_P_8021Q and TPID2 to be
ETH_P_8021AD. The meaning from the original E/T was chosen over P/Q/R/S
because E/T is actually the one with public documentation available
(UM10944.pdf).

Fixes: f9a1a764 ("net: dsa: sja1105: Reverse TPID and TPID2")
Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Since commit 86db36a3 ("net: dsa: sja1105: Implement state machine
for TAS with PTP clock source"), this paragraph is no longer true. So
remove it.
Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The check originates from the initial implementation which was not based
on PTP time but on a standalone clock source. In the meantime we can now
program the PTPSCHTM register at runtime with the dynamic base time
(actually with a value that is 200 ns smaller, to avoid writing DELTA=0
in the Schedule Entry Points Parameters Table). And we also have logic
for moving the actual base time in the future of the PHC's current time
base, so the check for zero serves no purpose, since even if the user
will specify zero, that's not what will end up in the static config
table where the limitation is.

Fixes: 86db36a3 ("net: dsa: sja1105: Implement state machine for TAS with PTP clock source")
Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

When activating tc-taprio offload on the switch ports, the TAS state
machine will try to check whether it is running or not, but will find
both the STARTED and STOPPED bits as false in the
sja1105_tas_check_running function. So the function will return -EINVAL
(an abnormal situation) and the kernel will keep printing this from the
TAS FSM workqueue:

[   37.691971] sja1105 spi0.1: An operation returned -22

The reason is that the underlying function that gets called,
sja1105_ptp_commit, does not actually do a SPI_READ, but a SPI_WRITE. So
the command buffer remains initialized with zeroes instead of retrieving
the hardware state. Fix that.

Fixes: 41603d78 ("net: dsa: sja1105: Make the PTP command read-write")
Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The PTP egress timestamp N must be captured from register PTPEGR_TS[n],
where n = 2 * PORT + TSREG. There are 10 PTPEGR_TS registers, 2 per
port. We are only using TSREG=0.

As opposed to the management slots, which are 4 in number
(SJA1105_NUM_PORTS, minus the CPU port). Any management frame (which
includes PTP frames) can be sent to any non-CPU port through any
management slot. When the CPU port is not the last port (#4), there will
be a mismatch between the slot and the port number.

Luckily, the only mainline occurrence with this switch
(arch/arm/boot/dts/ls1021a-tsn.dts) does have the CPU port as #4, so the
issue did not manifest itself thus far.

Fixes: 47ed985e ("net: dsa: sja1105: Add logic for TX timestamping")
Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

As per 802.3-2005, Section Two, Annex 28B, Table 28B-2 [1], when
_only_ Rx pause is enabled, both symmetric and asymmetric pause
towards local device must be enabled. Also, firmware returns the local
device's flow control pause params as part of advertised capabilities
and negotiated params as part of current link attributes. So, fix up
ethtool's flow control pause params fetch logic to read from acaps,
instead of linkattr.

[1] https://standards.ieee.org/standard/802_3-2005.html

Fixes: c3168cab ("cxgb4/cxgbvf: Handle 32-bit fw port capabilities")
Signed-off-by: Surendra Mobiya <surendra@chelsio.com>
Signed-off-by: Rahul Lakkireddy <rahul.lakkireddy@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Ido Schimmel says:

====================
mlxsw: Couple of fixes

This patch set contains two fixes for mlxsw. Please consider both for
stable.

Patch #1 from Amit fixes a wrong check during MAC validation when
creating router interfaces (RIFs). Given a particular order of
configuration this can result in the driver refusing to create new RIFs.

Patch #2 fixes a wrong trap configuration in which VRRP packets and
routing exceptions were policed by the same policer towards the CPU. In
certain situations this can prevent VRRP packets from reaching the CPU.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Currently, VRRP packets and packets that hit exceptions during routing
(e.g., MTU error) are policed using the same policer towards the CPU.
This means, for example, that misconfiguration of the MTU on a routed
interface can prevent VRRP packets from reaching the CPU, which in turn
can cause the VRRP daemon to assume it is the Master router.

Fix this by using a dedicated policer for VRRP packets.

Fixes: 11566d34 ("mlxsw: spectrum: Add VRRP traps")
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Reported-by: Alex Veber <alexve@mellanox.com>
Tested-by: Alex Veber <alexve@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

When a router interface (RIF) is created the MAC address of the backing
netdev is verified to have the same MSBs as existing RIFs. This is
required in order to avoid changing existing RIF MAC addresses that all
share the same MSBs.

Loopback RIFs are special in this regard as they do not have a MAC
address, given they are only used to loop packets from the overlay to
the underlay.

Without this change, an error is returned when trying to create a RIF
after the creation of a GRE tunnel that is represented by a loopback
RIF. 'rif->dev->dev_addr' points to the GRE device's local IP, which
does not share the same MSBs as physical interfaces. Adding an IP
address to any physical interface results in:

Error: mlxsw_spectrum: All router interface MAC addresses must have the
same prefix.

Fix this by skipping loopback RIFs during MAC validation.

Fixes: 74bc9939 ("mlxsw: spectrum_router: Veto unsupported RIF MAC addresses")
Signed-off-by: Amit Cohen <amitc@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Pull RISC-V fixes from Paul Walmsley:
 "One important fix for RISC-V:

   - Redirect any incoming syscall with an ID less than -1 to
     sys_ni_syscall, rather than allowing them to fall through into the
     syscall handler.

  and two minor build fixes:

   - Export __asm_copy_{from,to}_user() from where they are defined.
     This fixes a build error triggered by some randconfigs.

   - Export flush_icache_all(). I'd resisted this before, since
     historically we didn't want modules to be able to flush the I$
     directly; but apparently everyone else is doing it now"

* tag 'riscv/for-v5.5-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
  riscv: export flush_icache_all to modules
  riscv: reject invalid syscalls below -1
  riscv: fix compile failure with EXPORT_SYMBOL() & !MMU