unix_bind_bsd() and unix_bind_abstract() respectively.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

We do get some duplication that way, but it's minor compared to
parts that are different.  What we get is an ability to change
locking in BSD case without making failure exits very hard to
follow.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

makes it easier to massage; we do pay for that by extra work
(kmalloc+memcpy+kfree) in some error cases, but those are not
on the hot paths anyway.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

Duplicated logics in all bind variants (autobind, bind-to-path,
bind-to-abstract) gets taken into a common helper.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

The nfp_fl_ct_add_flow() function can fail so we need to check for
failure.

Fixes: 95255017 ("nfp: flower-ct: add nft flows to nft list")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Louis Peens <louis.peens@corigine.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

We recently changed these two pointers from void pointers to struct
pointers and it breaks the pointer math so now the "txphdr" points
beyond the end of the buffer.

Fixes: 56a967c4 ("net: qualcomm: rmnet: Remove some unneeded casts")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Subash Abhinov Kasiviswanathan <subashab@codeaurora.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

The address of &ipc_mux->ul_adb can't be NULL because it points to the
middle of a non-NULL struct.

Fixes: 9413491e ("net: iosm: encode or decode datagram")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: M Chetan Kumar <m.chetan.kumar@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

These functions return negative ENODATA but the minus sign was left out
in the tests.

Fixes: f0dd7bf5 ("net/smc: Add netlink support for SMC fallback statistics")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Guvenc Gulce <guvenc@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

These flags are used to set and test bits like this:

	if (!test_bit(HCLGE_PTP_FLAG_TX_EN, &ptp->flags) ||

The issue is that test_bit() takes a bit number like 1, but we are
passing BIT(1) instead and it's testing BIT(BIT(1)).  This does not
cause a problem because it is always done consistently and the bit
values are very small.

Fixes: 0bf5eb78 ("net: hns3: add support for PTP")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

This patch doesn't affect runtime at all, it's just a correctness issue.

The ptp->info.name[] buffer has 16 characters but the snprintf() limit
was capped at 32 characters.  Fortunately, HCLGE_DRIVER_NAME is "hclge"
which isn't close to 16 characters so we're fine.

Fixes: 0bf5eb78 ("net: hns3: add support for PTP")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ChaCha support did not adjust the bidirectional test.
We need to set up KTLS in reverse direction correctly,
otherwise these two cases will fail:

  tls.12_chacha.bidir
  tls.13_chacha.bidir

Fixes: 4f336e88 ("selftests/tls: add CHACHA20-POLY1305 to tls selftests")
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Acked-by: Vadim Fedorenko <vfedorenko@novek.ru>
Signed-off-by: David S. Miller <davem@davemloft.net>

A bunch of tests uses uninitialized stack memory as random
data to send. This is harmless but generates compiler warnings.
Explicitly init the buffers with random data.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Acked-by: Vadim Fedorenko <vfedorenko@novek.ru>
Signed-off-by: David S. Miller <davem@davemloft.net>

Trivial conflicts in net/can/isotp.c and
tools/testing/selftests/net/mptcp/mptcp_connect.sh

scaled_ppm_to_ppb() was moved from drivers/ptp/ptp_clock.c
to include/linux/ptp_clock_kernel.h in -next so re-apply
the fix there.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Pull networking fixes from Jakub Kicinski:
 "Networking fixes for 5.13-rc7, including fixes from wireless, bpf,
  bluetooth, netfilter and can.

  Current release - regressions:

   - mlxsw: spectrum_qdisc: Pass handle, not band number to find_class()
     to fix modifying offloaded qdiscs

   - lantiq: net: fix duplicated skb in rx descriptor ring

   - rtnetlink: fix regression in bridge VLAN configuration, empty info
     is not an error, bot-generated "fix" was not needed

   - libbpf: s/rx/tx/ typo on umem->rx_ring_setup_done to fix umem
     creation

  Current release - new code bugs:

   - ethtool: fix NULL pointer dereference during module EEPROM dump via
     the new netlink API

   - mlx5e: don't update netdev RQs with PTP-RQ, the special purpose
     queue should not be visible to the stack

   - mlx5e: select special PTP queue only for SKBTX_HW_TSTAMP skbs

   - mlx5e: verify dev is present in get devlink port ndo, avoid a panic

  Previous releases - regressions:

   - neighbour: allow NUD_NOARP entries to be force GCed

   - further fixes for fallout from reorg of WiFi locking (staging:
     rtl8723bs, mac80211, cfg80211)

   - skbuff: fix incorrect msg_zerocopy copy notifications

   - mac80211: fix NULL ptr deref for injected rate info

   - Revert "net/mlx5: Arm only EQs with EQEs" it may cause missed IRQs

  Previous releases - always broken:

   - bpf: more speculative execution fixes

   - netfilter: nft_fib_ipv6: skip ipv6 packets from any to link-local

   - udp: fix race between close() and udp_abort() resulting in a panic

   - fix out of bounds when parsing TCP options before packets are
     validated (in netfilter: synproxy, tc: sch_cake and mptcp)

   - mptcp: improve operation under memory pressure, add missing
     wake-ups

   - mptcp: fix double-lock/soft lookup in subflow_error_report()

   - bridge: fix races (null pointer deref and UAF) in vlan tunnel
     egress

   - ena: fix DMA mapping function issues in XDP

   - rds: fix memory leak in rds_recvmsg

  Misc:

   - vrf: allow larger MTUs

   - icmp: don't send out ICMP messages with a source address of 0.0.0.0

   - cdc_ncm: switch to eth%d interface naming"

* tag 'net-5.13-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (139 commits)
  net: ethernet: fix potential use-after-free in ec_bhf_remove
  selftests/net: Add icmp.sh for testing ICMP dummy address responses
  icmp: don't send out ICMP messages with a source address of 0.0.0.0
  net: ll_temac: Avoid ndo_start_xmit returning NETDEV_TX_BUSY
  net: ll_temac: Fix TX BD buffer overwrite
  net: ll_temac: Add memory-barriers for TX BD access
  net: ll_temac: Make sure to free skb when it is completely used
  MAINTAINERS: add Guvenc as SMC maintainer
  bnxt_en: Call bnxt_ethtool_free() in bnxt_init_one() error path
  bnxt_en: Fix TQM fastpath ring backing store computation
  bnxt_en: Rediscover PHY capabilities after firmware reset
  cxgb4: fix wrong shift.
  mac80211: handle various extensible elements correctly
  mac80211: reset profile_periodicity/ema_ap
  cfg80211: avoid double free of PMSR request
  cfg80211: make certificate generation more robust
  mac80211: minstrel_ht: fix sample time check
  net: qed: Fix memcpy() overflow of qed_dcbx_params()
  net: cdc_eem: fix tx fixup skb leak
  net: hamradio: fix memory leak in mkiss_close
  ...

Pull btrfs fix from David Sterba:
 "One more fix, for a space accounting bug in zoned mode. It happens
  when a block group is switched back rw->ro and unusable bytes (due to
  zoned constraints) are subtracted twice.

  It has user visible effects so I consider it important enough for late
  -rc inclusion and backport to stable"

* tag 'for-5.13-rc6-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  btrfs: zoned: fix negative space_info->bytes_readonly

Pull PCI fixes from Bjorn Helgaas:

 - Clear 64-bit flag for host bridge windows below 4GB to fix a resource
   allocation regression added in -rc1 (Punit Agrawal)

 - Fix tegra194 MCFG quirk build regressions added in -rc1 (Jon Hunter)

 - Avoid secondary bus resets on TI KeyStone C667X devices (Antti
   Järvinen)

 - Avoid secondary bus resets on some NVIDIA GPUs (Shanker Donthineni)

 - Work around FLR erratum on Huawei Intelligent NIC VF (Chiqijun)

 - Avoid broken ATS on AMD Navi14 GPU (Evan Quan)

 - Trust Broadcom BCM57414 NIC to isolate functions even though it
   doesn't advertise ACS support (Sriharsha Basavapatna)

 - Work around AMD RS690 BIOSes that don't configure DMA above 4GB
   (Mikel Rychliski)

 - Fix panic during PIO transfer on Aardvark controller (Pali Rohár)

* tag 'pci-v5.13-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci:
  PCI: aardvark: Fix kernel panic during PIO transfer
  PCI: Add AMD RS690 quirk to enable 64-bit DMA
  PCI: Add ACS quirk for Broadcom BCM57414 NIC
  PCI: Mark AMD Navi14 GPU ATS as broken
  PCI: Work around Huawei Intelligent NIC VF FLR erratum
  PCI: Mark some NVIDIA GPUs to avoid bus reset
  PCI: Mark TI C667X to avoid bus reset
  PCI: tegra194: Fix MCFG quirk build regressions
  PCI: of: Clear 64-bit flag for non-prefetchable memory below 4GB

If a task is killed during a page fault, it does not currently call
sb_end_pagefault(), which means that the filesystem cannot be frozen
at any time thereafter.  This may be reported by lockdep like this:

====================================
WARNING: fsstress/10757 still has locks held!
5.13.0-rc4-build4+ #91 Not tainted
------------------------------------
1 lock held by fsstress/10757:
 #0: ffff888104eac530
 (
sb_pagefaults

as filesystem freezing is modelled as a lock.

Fix this by removing all the direct returns from within the function,
and using 'ret' to indicate whether we were interrupted or successful.

Fixes: 1cf7a151 ("afs: Implement shared-writeable mmap")
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: David Howells <dhowells@redhat.com>
cc: linux-afs@lists.infradead.org
Link: https://lore.kernel.org/r/20210616154900.1958373-1-willy@infradead.org/Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Stephan Gerhold says:

====================
net: wwan: Add RPMSG WWAN CTRL driver

This patch series adds a WWAN "control" driver for the remote processor
messaging (rpmsg) subsystem. This subsystem allows communicating with
an integrated modem DSP on many Qualcomm SoCs, e.g. MSM8916 or MSM8974.

The driver is a fairly simple glue layer between WWAN and RPMSG
and is mostly based on the existing mhi_wwan_ctrl.c and rpmsg_char.c.

For more information, see commit message in PATCH 2/3.

I already posted a RFC for this a while ago:
https://lore.kernel.org/linux-arm-msm/YLfL9Q+4860uqS8f@gerhold.net/
and now I'm looking for some feedback for the actual changes. :)

Changes in v3:
  - PATCH 2/3: Clarify commit message
  - PATCH 3/3: Fix build error for cdc-wdm.c, use extra tx_blocking() op instead
v2: https://lore.kernel.org/netdev/20210618075243.42046-1-stephan@gerhold.net/

Changes in v2: Only in PATCH 3/3
  - Fix EPOLLOUT being always set even if poll op is defined
  - Rename poll() op -> tx_poll() since it should be only used for TX
v1: https://lore.kernel.org/netdev/20210615133229.213064-1-stephan@gerhold.net/
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

At the moment, the WWAN core provides wwan_port_txon/off() to implement
blocking writes. The tx() port operation should not block, instead
wwan_port_txon/off() should be called when the TX queue is full or has
free space again.

However, in some cases it is not straightforward to make use of that
functionality. For example, the RPMSG API used by rpmsg_wwan_ctrl.c
does not provide any way to be notified when the TX queue has space
again. Instead, it only provides the following operations:

  - rpmsg_send(): blocking write (wait until there is space)
  - rpmsg_trysend(): non-blocking write (return error if no space)
  - rpmsg_poll(): set poll flags depending on TX queue state

Generally that's totally sufficient for implementing a char device,
but it does not fit well to the currently provided WWAN port ops.

Most of the time, using the non-blocking rpmsg_trysend() in the
WWAN tx() port operation works just fine. However, with high-frequent
writes to the char device it is possible to trigger a situation
where this causes issues. For example, consider the following
(somewhat unrealistic) example:

 # dd if=/dev/zero bs=1000 of=/dev/wwan0qmi0
 dd: error writing '/dev/wwan0qmi0': Resource temporarily unavailable
 1+0 records out

This fails immediately after writing the first record. It's likely
only a matter of time until this triggers issues for some real application
(e.g. ModemManager sending a lot of large QMI packets).

The rpmsg_char device does not have this problem, because it uses
rpmsg_trysend() and rpmsg_poll() to support non-blocking operations.
Make it possible to use the same in the RPMSG WWAN driver by adding
two new optional wwan_port_ops:

  - tx_blocking(): send data blocking if allowed
  - tx_poll(): set additional TX poll flags

This integrates nicely with the RPMSG API and does not require
any change in existing WWAN drivers.

With these changes, the dd example above blocks instead of exiting
with an error.

Cc: Loic Poulain <loic.poulain@linaro.org>
Signed-off-by: Stephan Gerhold <stephan@gerhold.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

The remote processor messaging (rpmsg) subsystem provides an interface
to communicate with other remote processors. On many Qualcomm SoCs this
is used to communicate with an integrated modem DSP that implements most
of the modem functionality and provides high-level protocols like
QMI or AT to allow controlling the modem.

For QMI, most older Qualcomm SoCs (e.g. MSM8916/MSM8974) have
a standalone "DATA5_CNTL" channel that allows exchanging QMI messages.
Note that newer SoCs (e.g. SDM845) only allow exchanging QMI messages
via a shared QRTR channel that is available via a socket API on Linux.

For AT, the "DATA4" channel accepts at least a limited set of AT
commands, on many older and newer Qualcomm SoCs, although QMI is
typically the preferred control protocol.

Often there are additional QMI/AT channels (usually named DATA*_CNTL
for QMI and DATA* for AT), but it is not clear if those are really
functional on all devices. Also, at the moment there is no use case
for having multiple QMI/AT ports. If needed more channels could be
added later after more testing.

Note that the data path (network interface) is entirely separate
from the control path and varies between Qualcomm SoCs, e.g. "IPA"
on newer Qualcomm SoCs or "BAM-DMUX" on some older ones.

The RPMSG WWAN CTRL driver exposes the QMI/AT control ports via the
WWAN subsystem, and therefore allows userspace like ModemManager to
set up the modem. Until now, ModemManager had to use the RPMSG-specific
rpmsg-char where the channels must be explicitly exposed as a char
device first and don't show up directly in sysfs.

The driver is a fairly simple glue layer between WWAN and RPMSG
and is mostly based on the existing mhi_wwan_ctrl.c and rpmsg_char.c.

Cc: Loic Poulain <loic.poulain@linaro.org>
Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Stephan Gerhold <stephan@gerhold.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

Most device_id structs provide a driver_data field that can be used
by drivers to associate data more easily for a particular device ID.
Add the same for the rpmsg_device_id.

Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Stephan Gerhold <stephan@gerhold.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

Jesse Brandeburg says:

====================
100GbE Intel Wired LAN Driver Updates 2021-06-18

Update three of the Intel Ethernet drivers with similar (but not the
same) improvements to simplify the packet type table init, while removing
an unused structure entry. For the ice driver, the table is extended
to 10 bits, which is the hardware limit, and for now is initialized
to zero.

The end result is slightly reduced memory usage, removal of a bunch
of code, and more specific initialization.
====================
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>

This reverts commit 1f3c98ea.

Does not build...
Signed-off-by: David S. Miller <davem@davemloft.net>

Modify the pr_info content from int to char *, this looks more readable.
Signed-off-by: Yejune Deng <yejune.deng@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

static void ec_bhf_remove(struct pci_dev *dev)
{
...
	struct ec_bhf_priv *priv = netdev_priv(net_dev);

	unregister_netdev(net_dev);
	free_netdev(net_dev);

	pci_iounmap(dev, priv->dma_io);
	pci_iounmap(dev, priv->io);
...
}

priv is netdev private data, but it is used
after free_netdev(). It can cause use-after-free when accessing priv
pointer. So, fix it by moving free_netdev() after pci_iounmap()
calls.

Fixes: 6af55ff5 ("Driver for Beckhoff CX5020 EtherCAT master module.")
Signed-off-by: Pavel Skripkin <paskripkin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Stefano Garzarella says:

====================
vsock: small fixes for seqpacket support

This series contains few patches to clean up a bit the code
of seqpacket recently merged in the net-next tree.

No functionality changes.
====================
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>

When memcpy_to_msg() fails in virtio_transport_seqpacket_do_dequeue(),
we already set `dequeued_len` with the negative error value returned
by memcpy_to_msg().

So we can directly check `dequeued_len` value instead of using a
dedicated flag variable to skip the copy path for the rest of
fragments.
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

vsock_wait_data() is used only by STREAM and SEQPACKET sockets,
so let's rename it to vsock_connectible_wait_data(), using the same
nomenclature (connectible) used in other functions after the
introduction of SEQPACKET.
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

vsock_has_data() is used only by STREAM and SEQPACKET sockets,
so let's rename it to vsock_connectible_has_data(), using the same
nomenclature (connectible) used in other functions after the
introduction of SEQPACKET.
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Remove unnecessary label chunk_exit and return directly.
Signed-off-by: wengjianfeng <wengjianfeng@yulong.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

If reloading the static config fails for whatever reason, for example if
sja1105_static_config_check_valid() fails, then we "goto out_unlock_ptp"
but we print anyway that "Reset switch and programmed static config.",
which is confusing because we didn't. We also do a bunch of other stuff
like reprogram the XPCS and reload the credit-based shapers, as if a
switch reset took place, which didn't.

So just unlock the PTP lock and goto out, skipping all of that.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Currently sja1105_static_config_check_valid() is coded up to detect
whether TTEthernet is supported based on device ID, and this check was
not updated to cover SJA1110.

However, it is desirable to have as few checks for the device ID as
possible, so the driver core is more generic. So what we can do is look
at the static config table operations implemented by that specific
switch family (populated by sja1105_static_config_init) whether the
schedule table has a non-zero maximum entry count (meaning that it is
supported) or not.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

In the current rx page reuse handling process, the rx page buffer may
have conflict between driver and stack in high-pressure scenario.

To fix this problem, we need to check whether the page is only owned
by driver at the begin and at the end of a page to make sure there is
no reuse conflict between driver and stack when desc_cb->page_offset
is rollbacked to zero or increased.

Fixes: fa7711b8 ("net: hns3: optimize the rx page reuse handling process")
Signed-off-by: Yunsheng Lin <linyunsheng@huawei.com>
Signed-off-by: Guangbin Huang <huangguangbin2@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

It turns out that powering down the BASE_TIMER_CLK does not turn off the
microcontroller, just its timers, including the one for the watchdog.
So the embedded microcontroller is still running, and potentially still
doing things.

To prevent unwanted interference, we should power down the BASE_MCSS_CLK
as well (MCSS = microcontroller subsystem).

The trouble is that currently we turn off the BASE_TIMER_CLK for SJA1110
from the .clocking_setup() method, mostly because this is a Clock
Generation Unit (CGU) setting which was traditionally configured in that
method for SJA1105. But in SJA1105, the CGU was used for bringing up the
port clocks at the proper speeds, and in SJA1110 it's not (but rather
for initial configuration), so it's best that we rebrand the
sja1110_clocking_setup() method into what it really is - an implementation
of the .disable_microcontroller() method.

Since disabling the microcontroller only needs to be done once, at probe
time, we can choose the best place to do that as being in sja1105_setup(),
before we upload the static config to the device. This guarantees that
the static config being used by the switch afterwards is really ours.

Note that the procedure to upload a static config necessarily resets the
switch. This already did not reset the microcontroller, only the switch
core, so since the .disable_microcontroller() method is guaranteed to be
called by that point, if it's disabled, it remains disabled. Add a
comment to make that clear.

With the code movement for SJA1110 from .clocking_setup() to
.disable_microcontroller(), both methods are optional and are guarded by
"if" conditions.

Tested by enabling in the device tree the rev-mii switch port 0 that
goes towards the microcontroller, and flashing a firmware that would
have networking. Without this patch, the microcontroller can be pinged,
with this patch it cannot.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Merge tag 'mac80211-for-net-2021-06-18' of git://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211

Johannes Berg says:

====================
A couple of straggler fixes:
 * a minstrel HT sample check fix
 * peer measurement could double-free on races
 * certificate file generation at build time could
   sometimes hang
 * some parameters weren't reset between connections
   in mac80211
 * some extensible elements were treated as non-
   extensible, possibly causuing bad connections
   (or failures) if the AP adds data
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

This adds a new icmp.sh selftest for testing that the kernel will respond
correctly with an ICMP unreachable message with the dummy (192.0.0.8)
source address when there are no IPv4 addresses configured to use as source
addresses.
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

When constructing ICMP response messages, the kernel will try to pick a
suitable source address for the outgoing packet. However, if no IPv4
addresses are configured on the system at all, this will fail and we end up
producing an ICMP message with a source address of 0.0.0.0. This can happen
on a box routing IPv4 traffic via v6 nexthops, for instance.

Since 0.0.0.0 is not generally routable on the internet, there's a good
chance that such ICMP messages will never make it back to the sender of the
original packet that the ICMP message was sent in response to. This, in
turn, can create connectivity and PMTUd problems for senders. Fortunately,
RFC7600 reserves a dummy address to be used as a source for ICMP
messages (192.0.0.8/32), so let's teach the kernel to substitute that
address as a last resort if the regular source address selection procedure
fails.

Below is a quick example reproducing this issue with network namespaces:

ip netns add ns0
ip l add type veth peer netns ns0
ip l set dev veth0 up
ip a add 10.0.0.1/24 dev veth0
ip a add fc00:dead:cafe:42::1/64 dev veth0
ip r add 10.1.0.0/24 via inet6 fc00:dead:cafe:42::2
ip -n ns0 l set dev veth0 up
ip -n ns0 a add fc00:dead:cafe:42::2/64 dev veth0
ip -n ns0 r add 10.0.0.0/24 via inet6 fc00:dead:cafe:42::1
ip netns exec ns0 sysctl -w net.ipv4.icmp_ratelimit=0
ip netns exec ns0 sysctl -w net.ipv4.ip_forward=1
tcpdump -tpni veth0 -c 2 icmp &
ping -w 1 10.1.0.1 > /dev/null
tcpdump: verbose output suppressed, use -v[v]... for full protocol decode
listening on veth0, link-type EN10MB (Ethernet), snapshot length 262144 bytes
IP 10.0.0.1 > 10.1.0.1: ICMP echo request, id 29, seq 1, length 64
IP 0.0.0.0 > 10.0.0.1: ICMP net 10.1.0.1 unreachable, length 92
2 packets captured
2 packets received by filter
0 packets dropped by kernel

With this patch the above capture changes to:
IP 10.0.0.1 > 10.1.0.1: ICMP echo request, id 31127, seq 1, length 64
IP 192.0.0.8 > 10.0.0.1: ICMP net 10.1.0.1 unreachable, length 92

Fixes: 1da177e4 ("Linux-2.6.12-rc2")
Reported-by: Juliusz Chroboczek <jch@irif.fr>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

As documented in Documentation/networking/driver.rst, the ndo_start_xmit
method must not return NETDEV_TX_BUSY under any normal circumstances, and
as recommended, we simply stop the tx queue in advance, when there is a
risk that the next xmit would cause a NETDEV_TX_BUSY return.
Signed-off-by: Esben Haabendal <esben@geanix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Just as the initial check, we need to ensure num_frag+1 buffers available,
as that is the number of buffers we are going to use.

This fixes a buffer overflow, which might be seen during heavy network
load. Complete lockup of TEMAC was reproducible within about 10 minutes of
a particular load.

Fixes: 84823ff8 ("net: ll_temac: Fix race condition causing TX hang")
Cc: stable@vger.kernel.org # v5.4+
Signed-off-by: Esben Haabendal <esben@geanix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Add a couple of memory-barriers to ensure correct ordering of read/write
access to TX BDs.

In xmit_done, we should ensure that reading the additional BD fields are
only done after STS_CTRL_APP0_CMPLT bit is set.

When xmit_done marks the BD as free by setting APP0=0, we need to ensure
that the other BD fields are reset first, so we avoid racing with the xmit
path, which writes to the same fields.

Finally, making sure to read APP0 of next BD after the current BD, ensures
that we see all available buffers.
Signed-off-by: Esben Haabendal <esben@geanix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>