Currently, tagging protocol drivers have a modalias of
"dsa_tag:id-<number>", where the number is one of DSA_TAG_PROTO_*_VALUE.

This modalias makes it possible for the request_module() call in
dsa_tag_driver_get() to work, given the input it has - an integer
returned by ds->ops->get_tag_protocol().

It is also possible to change tagging protocols at (pseudo-)runtime, via
sysfs or via device tree, and this works via the name string of the
tagging protocol rather than via its id (DSA_TAG_PROTO_*_VALUE).

In the latter case, there is no request_module() call, because there is
no association that the DSA core has between the string name and the ID,
to construct the modalias. The module is simply assumed to have been
inserted. This is actually slightly problematic when the tagging
protocol change should take place at probe time, since it's expected
that the dependency module should get autoloaded.

For this purpose, let's introduce a second modalias, so that the DSA
core can call request_module() by name. There is no reason to make the
modalias by name optional, so just modify the MODULE_ALIAS_DSA_TAG_DRIVER()
macro to take both the ID and the name as arguments, and generate two
modaliases behind the scenes.
Suggested-by: Michael Walle <michael@walle.cc>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Tested-by: Michael Walle <michael@walle.cc> # on kontron-sl28 w/ ocelot_8021q
Tested-by: Michael Walle <michael@walle.cc>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

It's autumn cleanup time, and today's target are modaliases.

Michael says that for users of modinfo, "dsa_tag-20" is not the most
suggestive name, and recommends a change to "dsa_tag-id-20".

Andrew points out that other modaliases have a prefix delimited by
colons, so he recommends "dsa_tag:20" instead of "dsa_tag-20".

To satisfy both proposals, Florian recommends "dsa_tag:id-20".

The modaliases are not stable ABI, and the essential information
(protocol ID) is still conveyed in the new string, which
request_module() must be adapted to form.

Link: 20221027210830.3577793-1-vladimir.oltean@nxp.com
Suggested-by: Andrew Lunn <andrew@lunn.ch>
Suggested-by: Michael Walle <michael@walle.cc>
Suggested-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Tested-by: Michael Walle <michael@walle.cc>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

The DSA tagging protocol driver macros are in the public include/net/dsa.h
probably because that's also where the DSA_TAG_PROTO_*_VALUE macros are
(MODULE_ALIAS_DSA_TAG_DRIVER hinges on those macro definitions).

But there is no reason to expose these helpers to <net/dsa.h>. That
header is shared between switch drivers (drivers/net/dsa/), tagging
protocol drivers (net/dsa/tag_*.c), the DSA core (net/dsa/ sans tag_*.c),
and the rest of the world (DSA master drivers, network stack, etc).
Too much exposure.

On the other hand, net/dsa/dsa_priv.h is included only by the DSA core
and by DSA tagging protocol drivers (or IOW, "friend" modules). Also a
bit too much exposure - I've contemplated creating a new header which is
only included by tagging protocol drivers, but completely separating a
new dsa_tag_proto.h from dsa_priv.h is not immediately trivial - for
example dsa_slave_to_port() is used both from the fast path and from the
control path.

So for now, move these definitions to dsa_priv.h which at least hides
them from the world.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Tested-by: Michael Walle <michael@walle.cc>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

IPQ5018, IPQ6018 and IPQ8074 require clock-names to be set as driver is
requesting the clock based on it and not index, so document that and make
it required for the listed SoC-s.
Signed-off-by: Robert Marko <robimarko@gmail.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20221114194734.3287854-4-robimarko@gmail.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

Now that we can match the platforms requiring clocks by compatible start
using those to allow clocks per compatible and make them required.
Signed-off-by: Robert Marko <robimarko@gmail.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20221114194734.3287854-3-robimarko@gmail.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

Allow using IPQ8074 specific compatible along with the fallback IPQ4019
one in order to be able to specify which compatibles require clocks to
be able to validate them via schema.
Signed-off-by: Robert Marko <robimarko@gmail.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20221114194734.3287854-2-robimarko@gmail.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

Document IPQ6018 compatible that is already being used in the DTS along
with the fallback IPQ4019 compatible as driver itself only gets probed
on IPQ4019 and IPQ5018 compatibles.

This is also required in order to specify which platform require clock to
be defined and validate it in schema.
Signed-off-by: Robert Marko <robimarko@gmail.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20221114194734.3287854-1-robimarko@gmail.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

Rasmus Villemoes says:

====================
net: dsa: use more appropriate NET_NAME_* constants for user ports

The intention of commit 685343fc ("net: add name_assign_type
netdev attribute") was clearly that drivers be switched over one by
one to select appropriate NET_NAME_* constants instead of
NET_NAME_UNKNOWN. This small series attempts to do that for DSA user
ports.

This is obviously and intentionally user-visible changes, so there's a
small chance that it could lead to a regression. To make it easy to
revert either of the "label in DT" and "fallback to eth%d" changes,
this is done as a refactoring which shouldn't introduce any functional
change (but by itself adds code which looks a little odd, with the two
identical assignments in the two branches), followed by changing the
constant used in each case in two different patches.
====================

Link: https://lore.kernel.org/r/20221116105205.1127843-1-linux@rasmusvillemoes.dkSigned-off-by: Jakub Kicinski <kuba@kernel.org>

When a user port does not have a label in device tree, and we thus
fall back to the eth%d scheme, the proper constant to use is
NET_NAME_ENUM. See also commit e9f656b7 ("net: ethernet: set
default assignment identifier to NET_NAME_ENUM"), which in turn quoted
commit 685343fc ("net: add name_assign_type netdev attribute"):

    ... when the kernel has given the interface a name using global
    device enumeration based on order of discovery (ethX, wlanY, etc)
    ... are labelled NET_NAME_ENUM.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <f.faineli@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

When a user port has a label in device tree, the corresponding
netdevice is, to quote include/uapi/linux/netdevice.h, "predictably
named by the kernel". This is also explicitly one of the intended use
cases for NET_NAME_PREDICTABLE, quoting 685343fc ("net: add
name_assign_type netdev attribute"):

  NET_NAME_PREDICTABLE:
    The ifname has been assigned by the kernel in a predictable way
    [...] Examples include [...] and names deduced from hardware
    properties (including being given explicitly by the firmware).

Expose that information properly for the benefit of userspace tools
that make decisions based on the name_assign_type attribute,
e.g. a systemd-udev rule with "kernel" in NamePolicy.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <f.faineli@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

The following two patches each have a (small) chance of causing
regressions for userspace and will in that case of course need to be
reverted.

In order to prepare for that and make those two patches independent
and individually revertable, refactor the code which sets the names
for user ports by moving the "fall back to eth%d if no label is given
in device tree" to dsa_slave_create().

No functional change (at least none intended).
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <f.faineli@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Many of the drivers which implement ethtool_ops::get_drvinfo() will
prints the .driver, .version or .bus_info of struct ethtool_drvinfo.
To have a glance of current state, do:

  $ git grep -W "get_drvinfo(struct"

Printing in those three fields is useless because:

  - since [1], the driver version should be the kernel version (at
    least for upstream drivers). Arguably, out of tree drivers might
    still want to set a custom version, but out of tree is not our
    focus.

  - since [2], the core is able to provide default values for .driver
    and .bus_info.

In summary, drivers may provide .fw_version and .erom_version, the
rest is expected to be done by the core.

In struct ethtool_ops doc from linux/ethtool: rephrase field
get_drvinfo() doc to discourage developers from implementing this
callback.

In struct ethtool_drvinfo doc from uapi/linux/ethtool.h: remove the
paragraph mentioning what drivers should do. Rationale: no need to
repeat what is already written in struct ethtool_ops doc. But add a
note that .fw_version and .erom_version are driver defined.

Also update the dummy driver and simply remove the callback in order
not to confuse the newcomers: most of the drivers will not need this
callback function any more.

[1] commit 6a7e25c7 ("net/core: Replace driver version to be
    kernel version")
Link: https://git.kernel.org/torvalds/linux/c/6a7e25c7fb48

[2] commit edaf5df2 ("ethtool: ethtool_get_drvinfo: populate
    drvinfo fields even if callback exits")
Link: https://git.kernel.org/netdev/net-next/c/edaf5df22cb8Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Link: https://lore.kernel.org/r/20221116171828.4093-1-mailhol.vincent@wanadoo.frSigned-off-by: Jakub Kicinski <kuba@kernel.org>

include/linux/bpf.h
  1f6e04a1 ("bpf: Fix offset calculation error in __copy_map_value and zero_map_value")
  aa3496ac ("bpf: Refactor kptr_off_tab into btf_record")
  f71b2f64 ("bpf: Refactor map->off_arr handling")
https://lore.kernel.org/all/20221114095000.67a73239@canb.auug.org.au/Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Pull networking fixes from Paolo Abeni:
 "Including fixes from bpf.

  Current release - regressions:

   - tls: fix memory leak in tls_enc_skb() and tls_sw_fallback_init()

  Previous releases - regressions:

   - bridge: fix memory leaks when changing VLAN protocol

   - dsa: make dsa_master_ioctl() see through port_hwtstamp_get() shims

   - dsa: don't leak tagger-owned storage on switch driver unbind

   - eth: mlxsw: avoid warnings when not offloaded FDB entry with IPv6
     is removed

   - eth: stmmac: ensure tx function is not running in
     stmmac_xdp_release()

   - eth: hns3: fix return value check bug of rx copybreak

  Previous releases - always broken:

   - kcm: close race conditions on sk_receive_queue

   - bpf: fix alignment problem in bpf_prog_test_run_skb()

   - bpf: fix writing offset in case of fault in
     strncpy_from_kernel_nofault

   - eth: macvlan: use built-in RCU list checking

   - eth: marvell: add sleep time after enabling the loopback bit

   - eth: octeon_ep: fix potential memory leak in octep_device_setup()

  Misc:

   - tcp: configurable source port perturb table size

   - bpf: Convert BPF_DISPATCHER to use static_call() (not ftrace)"

* tag 'net-6.1-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (51 commits)
  net: use struct_group to copy ip/ipv6 header addresses
  net: usb: smsc95xx: fix external PHY reset
  net: usb: qmi_wwan: add Telit 0x103a composition
  netdevsim: Fix memory leak of nsim_dev->fa_cookie
  tcp: configurable source port perturb table size
  l2tp: Serialize access to sk_user_data with sk_callback_lock
  net: thunderbolt: Fix error handling in tbnet_init()
  net: microchip: sparx5: Fix potential null-ptr-deref in sparx_stats_init() and sparx5_start()
  net: lan966x: Fix potential null-ptr-deref in lan966x_stats_init()
  net: dsa: don't leak tagger-owned storage on switch driver unbind
  net/x25: Fix skb leak in x25_lapb_receive_frame()
  net: ag71xx: call phylink_disconnect_phy if ag71xx_hw_enable() fail in ag71xx_open()
  bridge: switchdev: Fix memory leaks when changing VLAN protocol
  net: hns3: fix setting incorrect phy link ksettings for firmware in resetting process
  net: hns3: fix return value check bug of rx copybreak
  net: hns3: fix incorrect hw rss hash type of rx packet
  net: phy: marvell: add sleep time after enabling the loopback bit
  net: ena: Fix error handling in ena_init()
  kcm: close race conditions on sk_receive_queue
  net: ionic: Fix error handling in ionic_init_module()
  ...

The rswitch_etha_wait_link_verification() is supposed to return zero
on success or negative error codes.  Unfortunately it is declared as a
bool so the caller treats everything as success.

Fixes: 3590918b ("net: ethernet: renesas: Add support for "Ethernet Switch"")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Link: https://lore.kernel.org/r/Y3OPo6AOL6PTvXFU@kiliSigned-off-by: Paolo Abeni <pabeni@redhat.com>

The current virtual nci driver is great for testing and fuzzing.
But it allows to create at most one "global" device which does not allow
to run parallel tests and harms fuzzing isolation and reproducibility.
Restructure the driver to allow creation of multiple independent devices.
This should be backwards compatible for existing tests.
Signed-off-by: Dmitry Vyukov <dvyukov@google.com>
Reviewed-by: Bongsu Jeon <bongsu.jeon@samsung.com>
Cc: Bongsu Jeon <bongsu.jeon@samsung.com>
Cc: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: netdev@vger.kernel.org
Link: https://lore.kernel.org/r/20221115100017.787929-1-dvyukov@google.comSigned-off-by: Paolo Abeni <pabeni@redhat.com>

Variable cnt is just being incremented and it's never used
anywhere else. The variable and the increment are redundant so
remove it.
Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
Link: https://lore.kernel.org/r/20221115093137.144002-1-colin.i.king@gmail.comSigned-off-by: Paolo Abeni <pabeni@redhat.com>

The subh.addip_hdr pointer is also of type (struct sctp_addiphdr *), so
it does not require a cast.
Signed-off-by: Li zeming <zeming@nfschina.com>
Link: https://lore.kernel.org/r/20221115020705.3220-1-zeming@nfschina.comSigned-off-by: Paolo Abeni <pabeni@redhat.com>

kernel test robot reported warnings when build bonding module with
make W=1 O=build_dir ARCH=x86_64 SHELL=/bin/bash drivers/net/bonding/:

                 from ../drivers/net/bonding/bond_main.c:35:
In function ‘fortify_memcpy_chk’,
    inlined from ‘iph_to_flow_copy_v4addrs’ at ../include/net/ip.h:566:2,
    inlined from ‘bond_flow_ip’ at ../drivers/net/bonding/bond_main.c:3984:3:
../include/linux/fortify-string.h:413:25: warning: call to ‘__read_overflow2_field’ declared with attribute warning: detected read beyond size of f
ield (2nd parameter); maybe use struct_group()? [-Wattribute-warning]
  413 |                         __read_overflow2_field(q_size_field, size);
      |                         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
In function ‘fortify_memcpy_chk’,
    inlined from ‘iph_to_flow_copy_v6addrs’ at ../include/net/ipv6.h:900:2,
    inlined from ‘bond_flow_ip’ at ../drivers/net/bonding/bond_main.c:3994:3:
../include/linux/fortify-string.h:413:25: warning: call to ‘__read_overflow2_field’ declared with attribute warning: detected read beyond size of f
ield (2nd parameter); maybe use struct_group()? [-Wattribute-warning]
  413 |                         __read_overflow2_field(q_size_field, size);
      |                         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

This is because we try to copy the whole ip/ip6 address to the flow_key,
while we only point the to ip/ip6 saddr. Note that since these are UAPI
headers, __struct_group() is used to avoid the compiler warnings.
Reported-by: kernel test robot <lkp@intel.com>
Fixes: c3f83241 ("net: Add full IPv6 addresses to flow_keys")
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Link: https://lore.kernel.org/r/20221115142400.1204786-1-liuhangbin@gmail.comSigned-off-by: Paolo Abeni <pabeni@redhat.com>

An external PHY needs settling time after power up or reset.
In the bind() function an mdio bus is registered. If at this point
the external PHY is still initialising, no valid PHY ID will be
read and on phy_find_first() the bind() function will fail.

If an external PHY is present, wait the maximum time specified
in 802.3 45.2.7.1.1.

Fixes: 05b35e7e ("smsc95xx: add phylib support")
Signed-off-by: Alexandru Tachici <alexandru.tachici@analog.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Link: https://lore.kernel.org/r/20221115114434.9991-2-alexandru.tachici@analog.comSigned-off-by: Paolo Abeni <pabeni@redhat.com>

Add the following Telit LE910C4-WWX composition:

0x103a: rmnet
Signed-off-by: Enrico Sau <enrico.sau@gmail.com>
Acked-by: Bjørn Mork <bjorn@mork.no>
Link: https://lore.kernel.org/r/20221115105859.14324-1-enrico.sau@gmail.comSigned-off-by: Paolo Abeni <pabeni@redhat.com>

kmemleak reports this issue:

unreferenced object 0xffff8881bac872d0 (size 8):
  comm "sh", pid 58603, jiffies 4481524462 (age 68.065s)
  hex dump (first 8 bytes):
    04 00 00 00 de ad be ef                          ........
  backtrace:
    [<00000000c80b8577>] __kmalloc+0x49/0x150
    [<000000005292b8c6>] nsim_dev_trap_fa_cookie_write+0xc1/0x210 [netdevsim]
    [<0000000093d78e77>] full_proxy_write+0xf3/0x180
    [<000000005a662c16>] vfs_write+0x1c5/0xaf0
    [<000000007aabf84a>] ksys_write+0xed/0x1c0
    [<000000005f1d2e47>] do_syscall_64+0x3b/0x90
    [<000000006001c6ec>] entry_SYSCALL_64_after_hwframe+0x63/0xcd

The issue occurs in the following scenarios:

nsim_dev_trap_fa_cookie_write()
  kmalloc() fa_cookie
  nsim_dev->fa_cookie = fa_cookie
..
nsim_drv_remove()

The fa_cookie allocked in nsim_dev_trap_fa_cookie_write() is not freed. To
fix, add kfree(nsim_dev->fa_cookie) to nsim_drv_remove().

Fixes: d3cbb907 ("netdevsim: add ACL trap reporting cookie as a metadata")
Signed-off-by: Wang Yufen <wangyufen@huawei.com>
Cc: Jiri Pirko <jiri@mellanox.com>
Link: https://lore.kernel.org/r/1668504625-14698-1-git-send-email-wangyufen@huawei.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

The mlxsw adjfine implementation in the spectrum_ptp.c file converts
scaled_ppm into ppb before updating a cyclecounter multiplier using the
standard "base * ppb / 1billion" calculation.

This can be re-written to use adjust_by_scaled_ppm, directly using the
scaled parts per million and reducing the amount of code required to
express this calculation.

We still calculate the parts per billion for passing into
mlxsw_sp_ptp_phc_adjfreq because this function requires the input to be in
parts per billion.
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Cc: Amit Cohen <amcohen@nvidia.com>
Cc: Petr Machata <petrm@nvidia.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Tested-by: Ido Schimmel <idosch@nvidia.com>
Link: https://lore.kernel.org/r/20221114213701.815132-1-jacob.e.keller@intel.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

Pull xen fixes from Juergen Gross:
 "Two trivial cleanups, and three simple fixes"

* tag 'for-linus-6.1-rc6-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  xen/platform-pci: use define instead of literal number
  xen/platform-pci: add missing free_irq() in error path
  xen-pciback: Allow setting PCI_MSIX_FLAGS_MASKALL too
  xen/pcpu: fix possible memory leak in register_pcpu()
  x86/xen: Use kstrtobool() instead of strtobool()

Pull pin control fixes from Linus Walleij:
 "Aere is a hopefully final round of pin control fixes. Nothing special,
  driver fixes and we caught a potential NULL pointer exception.

   - Fix a potential NULL dereference in the core!

   - Fix all pin mux routes in the Rockchop PX30 driver

   - Fix the UFS pins in the Qualcomm SC8280XP driver

   - Fix bias disabling in the Mediatek driver

   - Fix debounce time settings in the Mediatek driver"

* tag 'pinctrl-v6.1-4' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl:
  pinctrl: mediatek: Export debounce time tables
  pinctrl: mediatek: Fix EINT pins input debounce time configuration
  pinctrl: devicetree: fix null pointer dereferencing in pinctrl_dt_to_map
  pinctrl: mediatek: common-v2: Fix bias-disable for PULL_PU_PD_RSEL_TYPE
  pinctrl: qcom: sc8280xp: Rectify UFS reset pins
  pinctrl: rockchip: list all pins in a possible mux route for PX30

Merge tag 'platform-drivers-x86-v6.1-4' of git://git.kernel.org/pub/scm/linux/kernel/git/pdx86/platform-drivers-x86

Pull x86 platform driver fixes from Hans de Goede:

 - Surface Pro 9 and Surface Laptop 5 kbd, battery, etc support (this
   is just a few hw-id additions)

 - A couple of other hw-id / DMI-quirk additions

 - A few small bug fixes + 1 build fix

* tag 'platform-drivers-x86-v6.1-4' of git://git.kernel.org/pub/scm/linux/kernel/git/pdx86/platform-drivers-x86:
  platform/x86: ideapad-laptop: Add module parameters to match DMI quirk tables
  platform/x86: ideapad-laptop: Fix interrupt storm on fn-lock toggle on some Yoga laptops
  platform/x86: hp-wmi: Ignore Smart Experience App event
  platform/surface: aggregator_registry: Add support for Surface Laptop 5
  platform/surface: aggregator_registry: Add support for Surface Pro 9
  platform/surface: aggregator: Do not check for repeated unsequenced packets
  platform/x86: acer-wmi: Enable SW_TABLET_MODE on Switch V 10 (SW5-017)
  platform/x86: asus-wmi: add missing pci_dev_put() in asus_wmi_set_xusb2pr()
  platform/x86/intel: pmc: Don't unconditionally attach Intel PMC when virtualized
  platform/x86: thinkpad_acpi: Enable s2idle quirk for 21A1 machine type
  platform/x86/amd: pmc: Add new ACPI ID AMDI0009
  platform/x86/amd: pmc: Remove more CONFIG_DEBUG_FS checks

Annotate the lockless read of queue->synflood_warned.

Following xchg() has the needed data-race resolution.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The valptr pointer is of (void *) type, so other pointers need not be
forced to assign values to it.
Signed-off-by: Li zeming <zeming@nfschina.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

On embedded systems with little memory and no relevant
security concerns, it is beneficial to reduce the size
of the table.

Reducing the size from 2^16 to 2^8 saves 255 KiB
of kernel RAM.

Makes the table size configurable as an expert option.

The size was previously increased from 2^8 to 2^16
in commit 4c2c8f03 ("tcp: increase source port perturb table to
2^16").
Signed-off-by: Gleb Mazovetskiy <glex.spb@gmail.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sk->sk_user_data has multiple users, which are not compatible with each
other. Writers must synchronize by grabbing the sk->sk_callback_lock.

l2tp currently fails to grab the lock when modifying the underlying tunnel
socket fields. Fix it by adding appropriate locking.

We err on the side of safety and grab the sk_callback_lock also inside the
sk_destruct callback overridden by l2tp, even though there should be no
refs allowing access to the sock at the time when sk_destruct gets called.

v4:
- serialize write to sk_user_data in l2tp sk_destruct

v3:
- switch from sock lock to sk_callback_lock
- document write-protection for sk_user_data

v2:
- update Fixes to point to origin of the bug
- use real names in Reported/Tested-by tags

Cc: Tom Parkin <tparkin@katalix.com>
Fixes: 3557baab ("[L2TP]: PPP over L2TP driver core")
Reported-by: Haowei Yan <g1042620637@gmail.com>
Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Eric Dumazet says:

====================
net: add atomic dev->stats infra

Long standing KCSAN issues are caused by data-race around
some dev->stats changes.

Most performance critical paths already use per-cpu
variables, or per-queue ones.

It is reasonable (and more correct) to use atomic operations
for the slow paths.

First patch adds the infrastructure, then three patches address
the most common paths that syzbot is playing with.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Most of code paths in tunnels are lockless (eg NETIF_F_LLTX in tx).

Adopt SMP safe DEV_STATS_INC() to update dev->stats fields.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Most of code paths in tunnels are lockless (eg NETIF_F_LLTX in tx).

Adopt SMP safe DEV_STATS_{INC|ADD}() to update dev->stats fields.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

syzbot/KCSAN reported that multiple cpus are updating dev->stats.tx_error
concurrently.

This is because sit tunnels are NETIF_F_LLTX, meaning their ndo_start_xmit()
is not protected by a spinlock.

While original KCSAN report was about tx path, rx path has the same issue.
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Long standing KCSAN issues are caused by data-race around
some dev->stats changes.

Most performance critical paths already use per-cpu
variables, or per-queue ones.

It is reasonable (and more correct) to use atomic operations
for the slow paths.

This patch adds an union for each field of net_device_stats,
so that we can convert paths that are not yet protected
by a spinlock or a mutex.

netdev_stats_to_stats64() no longer has an #if BITS_PER_LONG==64

Note that the memcpy() we were using on 64bit arches
had no provision to avoid load-tearing,
while atomic_long_read() is providing the needed protection
at no cost.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Eric Dumazet says:

====================
net: more try_cmpxchg() conversions

Adopt try_cmpxchg() and friends in more places, as this
is preferred nowadays.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Adopt atomic64_try_cmpxchg() and remove the loop,
to make the intent more obvious.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

This makes code a bit cleaner.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

This makes the code slightly more efficient.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Adopting atomic_try_cmpxchg() makes the code cleaner.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>