net: partial revert of the "Make timestamping selectable: series

Revert following commits:

commit acec05fb78ab ("net_tstamp: Add TIMESTAMPING SOFTWARE and HARDWARE mask")
commit 11d55be06df0 ("net: ethtool: Add a command to expose current time stamping layer")
commit bb8645b00ced ("netlink: specs: Introduce new netlink command to get current timestamp")
commit d905f9c75329 ("net: ethtool: Add a command to list available time stamping layers")
commit aed5004ee7a0 ("netlink: specs: Introduce new netlink command to list available time stamping layers")
commit 51bdf3165f01 ("net: Replace hwtstamp_source by timestamping layer")
commit 0f7f463d4821 ("net: Change the API of PHY default timestamp to MAC")
commit 091fab122869 ("net: ethtool: ts: Update GET_TS to reply the current selected timestamp")
commit 152c75e1d002 ("net: ethtool: ts: Let the active time stamping layer be selectable")
commit ee60ea6be0d3 ("netlink: specs: Introduce time stamping set command")

They need more time for reviews.

Link: https://lore.kernel.org/all/20231118183529.6e67100c@kernel.org/
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: Change the API of PHY default timestamp to MAC

Change the API to select MAC default time stamping instead of the PHY.
Indeed the PHY is closer to the wire therefore theoretically it has less
delay than the MAC timestamping but the reality is different. Due to lower
time stamping clock frequency, latency in the MDIO bus and no PHC hardware
synchronization between different PHY, the PHY PTP is often less precise
than the MAC. The exception is for PHY designed specially for PTP case but
these devices are not very widespread. For not breaking the compatibility I
introduce a default_timestamp flag in phy_device that is set by the phy
driver to know we are using the old API behavior.

The phy_set_timestamp function is called at each call of phy_attach_direct.
In case of MAC driver using phylink this function is called when the
interface is turned up. Then if the interface goes down and up again the
last choice of timestamp will be overwritten by the default choice.
A solution could be to cache the timestamp status but it can bring other
issues. In case of SFP, if we change the module, it doesn't make sense to
blindly re-set the timestamp back to PHY, if the new module has a PHY with
mediocre timestamping capabilities.

Signed-off-by: Kory Maincent <kory.maincent@bootlin.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: Replace hwtstamp_source by timestamping layer

Replace hwtstamp_source which is only used by the kernel_hwtstamp_config
structure by the more widely use timestamp_layer structure. This is done
to prepare the support of selectable timestamping source.

Signed-off-by: Kory Maincent <kory.maincent@bootlin.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: Make dev_set_hwtstamp_phylib accessible

Make the dev_set_hwtstamp_phylib function accessible in prevision to use
it from ethtool to reset the tstamp current configuration.

Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com>
Signed-off-by: Kory Maincent <kory.maincent@bootlin.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: Use conduit and user terms

Use more inclusive terms throughout the DSA subsystem by moving away
from "master" which is replaced by "conduit" and "slave" which is
replaced by "user". No functional changes.

Acked-by: Rob Herring <robh@kernel.org>
Acked-by: Stephen Hemminger <stephen@networkplumber.org>
Reviewed-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: Florian Fainelli <florian.fainelli@broadcom.com>
Link: https://lore.kernel.org/r/20231023181729.1191071-2-florian.fainelli@broadcom.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: omit ndo_hwtstamp_get() call when possible in dev_set_hwtstamp_phylib()

Setting dev->priv_flags & IFF_SEE_ALL_HWTSTAMP_REQUESTS is only legal
for drivers which were converted to ndo_hwtstamp_get() and
ndo_hwtstamp_set(), and it is only there that we call ndo_hwtstamp_set()
for a request that otherwise goes to phylib (for stuff like packet traps,
which need to be undone if phylib failed, hence the old_cfg logic).

The problem is that we end up calling ndo_hwtstamp_get() when we don't
need to (even if the SIOCSHWTSTAMP wasn't intended for phylib, or if it
was, but the driver didn't set IFF_SEE_ALL_HWTSTAMP_REQUESTS). For those
unnecessary conditions, we share a code path with virtual drivers (vlan,
macvlan, bonding) where ndo_hwtstamp_get() is implemented as
generic_hwtstamp_get_lower(), and may be resolved through
generic_hwtstamp_ioctl_lower() if the lower device is unconverted.

I.e. this situation:

$ ip link add link eno0 name eno0.100 type vlan id 100
$ hwstamp_ctl -i eno0.100 -t 1

We are unprepared to deal with this, because if ndo_hwtstamp_get() is
resolved through a legacy ndo_eth_ioctl(SIOCGHWTSTAMP) lower_dev
implementation, that needs a non-NULL old_cfg.ifr pointer, and we don't
have it.

But we don't even need to deal with it either. In the general case,
drivers may not even implement SIOCGHWTSTAMP handling, only SIOCSHWTSTAMP,
so it makes sense to completely avoid a SIOCGHWTSTAMP call if we can.

The solution is to split the single "if" condition into 3 smaller ones,
thus separating the decision to call ndo_hwtstamp_get() from the
decision to call ndo_hwtstamp_set(). The third "if" condition is
identical to the first one, and both are subsets of the second one.
Thus, the "cfg" argument of kernel_hwtstamp_config_changed() is always
valid.

Reported-by: Eric Dumazet <edumazet@google.com>
Closes: https://lore.kernel.org/netdev/CANn89iLOspJsvjPj+y8jikg7erXDomWe8sqHMdfL_2LQSFrPAg@mail.gmail.com/
Fixes: fd770e856e22 ("net: remove phy_has_hwtstamp() -> phy_mii_ioctl() decision from converted drivers")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: remove phy_has_hwtstamp() -> phy_mii_ioctl() decision from converted drivers

It is desirable that the new .ndo_hwtstamp_set() API gives more
uniformity, less overhead and future flexibility w.r.t. the PHY
timestamping behavior.

Currently there are some drivers which allow PHY timestamping through
the procedure mentioned in Documentation/networking/timestamping.rst.
They don't do anything locally if phy_has_hwtstamp() is set, except for
lan966x which installs PTP packet traps.

Centralize that behavior in a new dev_set_hwtstamp_phylib() code
function, which calls either phy_mii_ioctl() for the phylib PHY,
or .ndo_hwtstamp_set() of the netdev, based on a single policy
(currently simplistic: phy_has_hwtstamp()).

Any driver converted to .ndo_hwtstamp_set() will automatically opt into
the centralized phylib timestamping policy. Unconverted drivers still
get to choose whether they let the PHY handle timestamping or not.

Netdev drivers with integrated PHY drivers that don't use phylib
presumably don't set dev->phydev, and those will always see
HWTSTAMP_SOURCE_NETDEV requests even when converted. The timestamping
policy will remain 100% up to them.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Tested-by: Horatiu Vultur <horatiu.vultur@microchip.com>
Link: https://lore.kernel.org/r/20230801142824.1772134-13-vladimir.oltean@nxp.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: add hwtstamping helpers for stackable net devices

The stackable net devices with hwtstamping support (vlan, macvlan,
bonding) only pass the hwtstamping ops to the lower (real) device.

These drivers are the first that need to be converted to the new
timestamping API, because if they aren't prepared to handle that,
then no real device driver cannot be converted to the new API either.

After studying what vlan_dev_ioctl(), macvlan_eth_ioctl() and
bond_eth_ioctl() have in common, here we propose two generic
implementations of ndo_hwtstamp_get() and ndo_hwtstamp_set() which
can be called by those 3 drivers, with "dev" being their lower device.

These helpers cover both cases, when the lower driver is converted to
the new API or unconverted.

We need some hacks in case of an unconverted driver, namely to stuff
some pointers in struct kernel_hwtstamp_config which shouldn't have
been there (since the new API isn't supposed to need it). These will
be removed when all drivers will have been converted to the new API.

Signed-off-by: Maxim Georgiev <glipus@gmail.com>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Link: https://lore.kernel.org/r/20230801142824.1772134-3-vladimir.oltean@nxp.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: add NDOs for configuring hardware timestamping

Current hardware timestamping API for NICs requires implementing
.ndo_eth_ioctl() for SIOCGHWTSTAMP and SIOCSHWTSTAMP.

That API has some boilerplate such as request parameter translation
between user and kernel address spaces, handling possible translation
failures correctly, etc. Since it is the same all across the board, it
would be desirable to handle it through generic code.

Here we introduce .ndo_hwtstamp_get() and .ndo_hwtstamp_set(), which
implement that boilerplate and allow drivers to just act upon requests.

Suggested-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Maxim Georgiev <glipus@gmail.com>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Tested-by: Horatiu Vultur <horatiu.vultur@microchip.com>
Link: https://lore.kernel.org/r/20230801142824.1772134-2-vladimir.oltean@nxp.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: dsa: replace NETDEV_PRE_CHANGE_HWTSTAMP notifier with a stub

There was a sort of rush surrounding commit 88c0a6b503b7 ("net: create a
netdev notifier for DSA to reject PTP on DSA master"), due to a desire
to convert DSA's attempt to deny TX timestamping on a DSA master to
something that doesn't block the kernel-wide API conversion from
ndo_eth_ioctl() to ndo_hwtstamp_set().

What was required was a mechanism that did not depend on ndo_eth_ioctl(),
and what was provided was a mechanism that did not depend on
ndo_eth_ioctl(), while at the same time introducing something that
wasn't absolutely necessary - a new netdev notifier.

There have been objections from Jakub Kicinski that using notifiers in
general when they are not absolutely necessary creates complications to
the control flow and difficulties to maintainers who look at the code.
So there is a desire to not use notifiers.

In addition to that, the notifier chain gets called even if there is no
DSA in the system and no one is interested in applying any restriction.

Take the model of udp_tunnel_nic_ops and introduce a stub mechanism,
through which net/core/dev_ioctl.c can call into DSA even when
CONFIG_NET_DSA=m.

Compared to the code that existed prior to the notifier conversion, aka
what was added in commits:
- 4cfab3566710 ("net: dsa: Add wrappers for overloaded ndo_ops")
- 3369afba1e46 ("net: Call into DSA netdevice_ops wrappers")

this is different because we are not overloading any struct
net_device_ops of the DSA master anymore, but rather, we are exposing a
rather specific functionality which is orthogonal to which API is used
to enable it - ndo_eth_ioctl() or ndo_hwtstamp_set().

Also, what is similar is that both approaches use function pointers to
get from built-in code to DSA.

There is no point in replicating the function pointers towards
__dsa_master_hwtstamp_validate() once for every CPU port (dev->dsa_ptr).
Instead, it is sufficient to introduce a singleton struct dsa_stubs,
built into the kernel, which contains a single function pointer to
__dsa_master_hwtstamp_validate().

I find this approach preferable to what we had originally, because
dev->dsa_ptr->netdev_ops->ndo_do_ioctl() used to require going through
struct dsa_port (dev->dsa_ptr), and so, this was incompatible with any
attempts to add any data encapsulation and hide DSA data structures from
the outside world.

Link: https://lore.kernel.org/netdev/20230403083019.120b72fd@kernel.org/
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: create a netdev notifier for DSA to reject PTP on DSA master

The fact that PTP 2-step TX timestamping is broken on DSA switches if
the master also timestamps the same packets is documented by commit
f685e609a301 ("net: dsa: Deny PTP on master if switch supports it").
We attempt to help the users avoid shooting themselves in the foot by
making DSA reject the timestamping ioctls on an interface that is a DSA
master, and the switch tree beneath it contains switches which are aware
of PTP.

The only problem is that there isn't an established way of intercepting
ndo_eth_ioctl calls, so DSA creates avoidable burden upon the network
stack by creating a struct dsa_netdevice_ops with overlaid function
pointers that are manually checked from the relevant call sites. There
used to be 2 such dsa_netdevice_ops, but now, ndo_eth_ioctl is the only
one left.

There is an ongoing effort to migrate driver-visible hardware timestamping
control from the ndo_eth_ioctl() based API to a new ndo_hwtstamp_set()
model, but DSA actively prevents that migration, since dsa_master_ioctl()
is currently coded to manually call the master's legacy ndo_eth_ioctl(),
and so, whenever a network device driver would be converted to the new
API, DSA's restrictions would be circumvented, because any device could
be used as a DSA master.

The established way for unrelated modules to react on a net device event
is via netdevice notifiers. So we create a new notifier which gets
called whenever there is an attempt to change hardware timestamping
settings on a device.

Finally, there is another reason why a netdev notifier will be a good
idea, besides strictly DSA, and this has to do with PHY timestamping.

With ndo_eth_ioctl(), all MAC drivers must manually call
phy_has_hwtstamp() before deciding whether to act upon SIOCSHWTSTAMP,
otherwise they must pass this ioctl to the PHY driver via
phy_mii_ioctl().

With the new ndo_hwtstamp_set() API, it will be desirable to simply not
make any calls into the MAC device driver when timestamping should be
performed at the PHY level.

But there exist drivers, such as the lan966x switch, which need to
install packet traps for PTP regardless of whether they are the layer
that provides the hardware timestamps, or the PHY is. That would be
impossible to support with the new API.

The proposal there, too, is to introduce a netdev notifier which acts as
a better cue for switching drivers to add or remove PTP packet traps,
than ndo_hwtstamp_set(). The one introduced here "almost" works there as
well, except for the fact that packet traps should only be installed if
the PHY driver succeeded to enable hardware timestamping, whereas here,
we need to deny hardware timestamping on the DSA master before it
actually gets enabled. This is why this notifier is called "PRE_", and
the notifier that would get used for PHY timestamping and packet traps
would be called NETDEV_CHANGE_HWTSTAMP. This isn't a new concept, for
example NETDEV_CHANGEUPPER and NETDEV_PRECHANGEUPPER do the same thing.

In expectation of future netlink UAPI, we also pass a non-NULL extack
pointer to the netdev notifier, and we make DSA populate it with an
informative reason for the rejection. To avoid making it go to waste, we
make the ioctl-based dev_set_hwtstamp() create a fake extack and print
the message to the kernel log.

Link: https://lore.kernel.org/netdev/20230401191215.tvveoi3lkawgg6g4@skbuf/
Link: https://lore.kernel.org/netdev/20230310164451.ls7bbs6pdzs4m6pw@skbuf/
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: add struct kernel_hwtstamp_config and make net_hwtstamp_validate() use it

Jakub Kicinski suggested that we may want to add new UAPI for
controlling hardware timestamping through netlink in the future, and in
that case, we will be limited to the struct hwtstamp_config that is
currently passed in fixed binary format through the SIOCGHWTSTAMP and
SIOCSHWTSTAMP ioctls. It would be good if new kernel code already
started operating on an extensible kernel variant of that structure,
similar in concept to struct kernel_ethtool_coalesce vs struct
ethtool_coalesce.

Since struct hwtstamp_config is in include/uapi/linux/net_tstamp.h, here
we introduce include/linux/net_tstamp.h which shadows that other header,
but also includes it, so that existing includers of this header work as
before. In addition to that, we add the definition for the kernel-only
structure, and a helper which translates all fields by manual copying.
I am doing a manual copy in order to not force the alignment (or type)
of the fields of struct kernel_hwtstamp_config to be the same as of
struct hwtstamp_config, even though now, they are the same.

Link: https://lore.kernel.org/netdev/20230330223519.36ce7d23@kernel.org/
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: move copy_from_user() out of net_hwtstamp_validate()

The kernel will want to start using the more meaningful struct
hwtstamp_config pointer in more places, so move the copy_from_user() at
the beginning of dev_set_hwtstamp() in order to get to that, and pass
this argument to net_hwtstamp_validate().

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: promote SIOCSHWTSTAMP and SIOCGHWTSTAMP ioctls to dedicated handlers

DSA does not want to intercept all ioctls handled by dev_eth_ioctl(),
only SIOCSHWTSTAMP. This can be seen from commit f685e609a301 ("net:
dsa: Deny PTP on master if switch supports it"). However, the way in
which the dsa_ndo_eth_ioctl() is called would suggest otherwise.

Split the handling of SIOCSHWTSTAMP and SIOCGHWTSTAMP ioctls into
separate case statements of dev_ifsioc(), and make each one call its own
sub-function. This also removes the dsa_ndo_eth_ioctl() call from
dev_eth_ioctl(), which from now on exclusively handles PHY ioctls.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: simplify handling of dsa_ndo_eth_ioctl() return code

In the expression "x == 0 || x != -95", the term "x == 0" does not
change the expression's logical value, because 0 != -95, and so,
if x is 0, the expression would still be true by virtue of the second
term. If x is non-zero, the expression depends on the truth value of
the second term anyway. As such, the first term is redundant and can
be deleted.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: don't abuse "default" case for unknown ioctl in dev_ifsioc()

The "switch (cmd)" block from dev_ifsioc() gained a bit too much
unnecessary manual handling of "cmd" in the "default" case, starting
with the private ioctls.

Clean that up by using the "ellipsis" gcc extension, adding separate
cases for the rest of the ioctls, and letting the default case only
return -EINVAL.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

dev_ioctl: fix a W=1 warning

This fixes the following warning when compiled with GCC 12.2.0 and W=1.

net/core/dev_ioctl.c:475: warning: Function parameter or member 'data'
not described in 'dev_ioctl'

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dev: Convert sa_data to flexible array in struct sockaddr

One of the worst offenders of "fake flexible arrays" is struct sockaddr,
as it is the classic example of why GCC and Clang have been traditionally
forced to treat all trailing arrays as fake flexible arrays: in the
distant misty past, sa_data became too small, and code started just
treating it as a flexible array, even though it was fixed-size. The
special case by the compiler is specifically that sizeof(sa->sa_data)
and FORTIFY_SOURCE (which uses __builtin_object_size(sa->sa_data, 1))
do not agree (14 and -1 respectively), which makes FORTIFY_SOURCE treat
it as a flexible array.

However, the coming -fstrict-flex-arrays compiler flag will remove
these special cases so that FORTIFY_SOURCE can gain coverage over all
the trailing arrays in the kernel that are _not_ supposed to be treated
as a flexible array. To deal with this change, convert sa_data to a true
flexible array. To keep the structure size the same, move sa_data into
a union with a newly introduced sa_data_min with the original size. The
result is that FORTIFY_SOURCE can continue to have no idea how large
sa_data may actually be, but anything using sizeof(sa->sa_data) must
switch to sizeof(sa->sa_data_min).

Cc: Jens Axboe <axboe@kernel.dk>
Cc: Pavel Begunkov <asml.silence@gmail.com>
Cc: David Ahern <dsahern@kernel.org>
Cc: Dylan Yudaken <dylany@fb.com>
Cc: Yajun Deng <yajun.deng@linux.dev>
Cc: Petr Machata <petrm@nvidia.com>
Cc: Hangbin Liu <liuhangbin@gmail.com>
Cc: Leon Romanovsky <leon@kernel.org>
Cc: syzbot <syzkaller@googlegroups.com>
Cc: Willem de Bruijn <willemb@google.com>
Cc: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20221018095503.never.671-kees@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: rename reference+tracking helpers

Netdev reference helpers have a dev_ prefix for historic
reasons. Renaming the old helpers would be too much churn
but we can rename the tracking ones which are relatively
recent and should be the default for new code.

Rename:
dev_hold_track() -> netdev_hold()
dev_put_track() -> netdev_put()
dev_replace_track() -> netdev_ref_replace()

Link: https://lore.kernel.org/r/20220608043955.919359-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: extract a few internals from netdevice.h

There's a number of functions and static variables used
under net/core/ but not from the outside. We currently
dump most of them into netdevice.h. That bad for many
reasons:
- netdevice.h is very cluttered, hard to figure out
what the APIs are;
- netdevice.h is very long;
- we have to touch netdevice.h more which causes expensive
incremental builds.

Create a header under net/core/ and move some declarations.

The new header is also a bit of a catch-all but that's
fine, if we create more specific headers people will
likely over-think where their declaration fit best.
And end up putting them in netdevice.h, again.

More work should be done on splitting netdevice.h into more
targeted headers, but that'd be more time consuming so small
steps.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net_tstamp: add new flag HWTSTAMP_FLAG_BONDED_PHC_INDEX

Since commit 94dd016ae538 ("bond: pass get_ts_info and SIOC[SG]HWTSTAMP
ioctl to active device") the user could get bond active interface's
PHC index directly. But when there is a failover, the bond active
interface will change, thus the PHC index is also changed. This may
break the user's program if they did not update the PHC timely.

This patch adds a new hwtstamp_config flag HWTSTAMP_FLAG_BONDED_PHC_INDEX.
When the user wants to get the bond active interface's PHC, they need to
add this flag and be aware the PHC index may be changed.

With the new flag. All flag checks in current drivers are removed. Only
the checking in net_hwtstamp_validate() is kept.

Suggested-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: add net device refcount tracker to dev_ifsioc()

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

ethtool: push the rtnl_lock into dev_ethtool()

Don't take the lock in net/core/dev_ioctl.c,
we'll have things to do outside rtnl_lock soon.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: core: don't call SIOCBRADD/DELIF for non-bridge devices

Commit ad2f99aedf8f ("net: bridge: move bridge ioctls out of .ndo_do_ioctl")
changed SIOCBRADD/DELIF to use bridge's ioctl hook (br_ioctl_hook)
without checking if the target netdevice is actually a bridge which can
cause crashes and generally interpreting other devices' private pointers
as net_bridge pointers.

Crash example (lo - loopback):
$ brctl addif lo ens16
BUG: kernel NULL pointer dereference, address: 000000000000059898
#PF: supervisor read access in kernel modede
#PF: error_code(0x0000) - not-present pagege
PGD 0 P4D 0 ^Ac
Oops: 0000 [#1] SMP NOPTI
CPU: 2 PID: 1376 Comm: brctl Kdump: loaded Tainted: G W 5.14.0-rc3+ #405
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-4.fc34 04/01/2014
RIP: 0010:add_del_if+0x1f/0x7c [bridge]
Code: 80 bf 1b a0 41 5c e9 c0 3c 03 e1 0f 1f 44 00 00 41 55 41 54 41 89 f4 be 0c 00 00 00 55 48 89 fd 53 48 8b 87 88 00 00 00 89 d3 <4c> 8b a8 98 05 00 00 49 8b bd d0 00 00 00 e8 17 d7 f3 e0 84 c0 74
RSP: 0018:ffff888109d97cb0 EFLAGS: 00010202^Ac
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 000000000000000c RDI: ffff888101239bc0
RBP: ffff888101239bc0 R08: 0000000000000001 R09: 0000000000000000
R10: ffff888109d97cd8 R11: 00000000000000a3 R12: 0000000000000012
R13: 0000000000000000 R14: ffff888101239bc0 R15: ffff888109d97e10
FS: 00007fc1e365b540(0000) GS:ffff88822be80000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000598 CR3: 0000000106506000 CR4: 00000000000006e0
Call Trace:
br_ioctl_stub+0x7c/0x441 [bridge]
br_ioctl_call+0x6d/0x8a
dev_ifsioc+0x325/0x4e8
dev_ioctl+0x46b/0x4e1
sock_do_ioctl+0x7b/0xad
sock_ioctl+0x2de/0x2f2
vfs_ioctl+0x1e/0x2b
__do_sys_ioctl+0x63/0x86
do_syscall_64+0xcb/0xf2
entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7fc1e3589427
Code: 00 00 90 48 8b 05 69 aa 0c 00 64 c7 00 26 00 00 00 48 c7 c0 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 b8 10 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 39 aa 0c 00 f7 d8 64 89 01 48
RSP: 002b:00007ffc8d501d38 EFLAGS: 00000202 ORIG_RAX: 000000000000001010
RAX: ffffffffffffffda RBX: 0000000000000012 RCX: 00007fc1e3589427
RDX: 00007ffc8d501d60 RSI: 00000000000089a3 RDI: 0000000000000003
RBP: 00007ffc8d501d60 R08: 0000000000000000 R09: fefefeff77686d74
R10: fffffffffffff8f9 R11: 0000000000000202 R12: 00007ffc8d502e06
R13: 00007ffc8d502e06 R14: 0000000000000000 R15: 0000000000000000
Modules linked in: bridge stp llc bonding ipv6 virtio_net [last unloaded: llc]^Ac
CR2: 0000000000000598

Reported-by: syzbot+79f4a8692e267bdb7227@syzkaller.appspotmail.com
Fixes: ad2f99aedf8f ("net: bridge: move bridge ioctls out of .ndo_do_ioctl")
Signed-off-by: Nikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: bridge: fix ioctl locking

Before commit ad2f99aedf8f ("net: bridge: move bridge ioctls out of
.ndo_do_ioctl") the bridge ioctl calls were divided in two parts:
one was deviceless called by sock_ioctl and didn't expect rtnl to be held,
the other was with a device called by dev_ifsioc() and expected rtnl to be
held. After the commit above they were united in a single ioctl stub, but
it didn't take care of the locking expectations.
For sock_ioctl now we acquire (1) br_ioctl_mutex, (2) rtnl
and for dev_ifsioc we acquire (1) rtnl, (2) br_ioctl_mutex

The fix is to get a refcnt on the netdev for dev_ifsioc calls and drop rtnl
then to reacquire it in the bridge ioctl stub after br_ioctl_mutex has
been acquired. That will avoid playing locking games and make the rules
straight-forward: we always take br_ioctl_mutex first, and then rtnl.

Reported-by: syzbot+34fe5894623c4ab1b379@syzkaller.appspotmail.com
Fixes: ad2f99aedf8f ("net: bridge: move bridge ioctls out of .ndo_do_ioctl")
Signed-off-by: Nikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: bonding: move ioctl handling to private ndo operation

All other user triggered operations are gone from ndo_ioctl, so move
the SIOCBOND family into a custom operation as well.

The .ndo_ioctl() helper is no longer called by the dev_ioctl.c code now,
but there are still a few definitions in obsolete wireless drivers as well
as the appletalk and ieee802154 layers to call SIOCSIFADDR/SIOCGIFADDR
helpers from inside the kernel.

Cc: Jay Vosburgh <j.vosburgh@gmail.com>
Cc: Veaceslav Falico <vfalico@gmail.com>
Cc: Andy Gospodarek <andy@greyhouse.net>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: bridge: move bridge ioctls out of .ndo_do_ioctl

Working towards obsoleting the .ndo_do_ioctl operation entirely,
stop passing the SIOCBRADDIF/SIOCBRDELIF device ioctl commands
into this callback.

My first attempt was to add another ndo_siocbr() callback, but
as there is only a single driver that takes these commands and
there is already a hook mechanism to call directly into this
driver, extend this hook instead, and use it for both the
deviceless and the device specific ioctl commands.

Cc: Roopa Prabhu <roopa@nvidia.com>
Cc: Nikolay Aleksandrov <nikolay@nvidia.com>
Cc: bridge@lists.linux-foundation.org
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: socket: return changed ifreq from SIOCDEVPRIVATE

Some drivers that use SIOCDEVPRIVATE ioctl commands modify
the ifreq structure and expect it to be passed back to user
space, which has never really happened for compat mode
because the calling these drivers through ndo_do_ioctl
requires overwriting the ifr_data pointer.

Now that all drivers are converted to ndo_siocdevprivate,
change it to handle this correctly in both compat and
native mode.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: split out ndo_siowandev ioctl

In order to further reduce the scope of ndo_do_ioctl(), move
out the SIOCWANDEV handling into a new network device operation
function.

Adjust the prototype to only pass the if_settings sub-structure
in place of the ifreq, and remove the redundant 'cmd' argument
in the process.

Cc: Krzysztof Halasa <khc@pm.waw.pl>
Cc: "Jan \"Yenya\" Kasprzak" <kas@fi.muni.cz>
Cc: Kevin Curtis <kevin.curtis@farsite.co.uk>
Cc: Zhao Qiang <qiang.zhao@nxp.com>
Cc: Martin Schiller <ms@dev.tdt.de>
Cc: Jiri Slaby <jirislaby@kernel.org>
Cc: linux-x25@vger.kernel.org
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

dev_ioctl: split out ndo_eth_ioctl

Most users of ndo_do_ioctl are ethernet drivers that implement
the MII commands SIOCGMIIPHY/SIOCGMIIREG/SIOCSMIIREG, or hardware
timestamping with SIOCSHWTSTAMP/SIOCGHWTSTAMP.

Separate these from the few drivers that use ndo_do_ioctl to
implement SIOCBOND, SIOCBR and SIOCWANDEV commands.

This is a purely cosmetic change intended to help readers find
their way through the implementation.

Cc: Doug Ledford <dledford@redhat.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Jay Vosburgh <j.vosburgh@gmail.com>
Cc: Veaceslav Falico <vfalico@gmail.com>
Cc: Andy Gospodarek <andy@greyhouse.net>
Cc: Andrew Lunn <andrew@lunn.ch>
Cc: Vivien Didelot <vivien.didelot@gmail.com>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: Vladimir Oltean <olteanv@gmail.com>
Cc: Leon Romanovsky <leon@kernel.org>
Cc: linux-rdma@vger.kernel.org
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

dev_ioctl: pass SIOCDEVPRIVATE data separately

The compat handlers for SIOCDEVPRIVATE are incorrect for any driver that
passes data as part of struct ifreq rather than as an ifr_data pointer, or
that passes data back this way, since the compat_ifr_data_ioctl() helper
overwrites the ifr_data pointer and does not copy anything back out.

Since all drivers using devprivate commands are now converted to the
new .ndo_siocdevprivate callback, fix this by adding the missing piece
and passing the pointer separately the whole way.

This further unifies the native and compat logic for socket ioctls,
as the new code now passes the correct pointer as well as the correct
data for both native and compat ioctls.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: split out SIOCDEVPRIVATE handling from dev_ioctl

SIOCDEVPRIVATE ioctl commands are mainly used in really old
drivers, and they have a number of problems:

- They hide behind the normal .ndo_do_ioctl function that
is also used for other things in modern drivers, so it's
hard to spot a driver that actually uses one of these

- Since drivers use a number different calling conventions,
it is impossible to support compat mode for them in
a generic way.

- With all drivers using the same 16 commands codes, there
is no way to introspect the data being passed through
things like strace.

Add a new net_device_ops callback pointer, to address the
first two of these. Separating them from .ndo_do_ioctl
makes it easy to grep for drivers with a .ndo_siocdevprivate
callback, and the unwieldy name hopefully makes it easier
to spot in code review.

By passing the ifreq structure and the ifr_data pointer
separately, it is no longer necessary to overload these,
and the driver can use either one for a given command.

Cc: Cong Wang <cong.wang@bytedance.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: socket: simplify dev_ifconf handling

The dev_ifconf() calling conventions make compat handling
more complicated than necessary, simplify this by moving
the in_compat_syscall() check into the function.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: socket: remove register_gifconf

Since dynamic registration of the gifconf() helper is only used for
IPv4, and this can not be in a loadable module, this can be simplified
noticeably by turning it into a direct function call as a preparation
for cleaning up the compat handling.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: socket: rework SIOC?IFMAP ioctls

SIOCGIFMAP and SIOCSIFMAP currently require compat_alloc_user_space()
and copy_in_user() for compat mode.

Move the compat handling into the location where the structures are
actually used, to avoid using those interfaces and get a clearer
implementation.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: fix dev_ifsioc_locked() race condition

dev_ifsioc_locked() is called with only RCU read lock, so when
there is a parallel writer changing the mac address, it could
get a partially updated mac address, as shown below:

Thread 1 Thread 2
// eth_commit_mac_addr_change()
memcpy(dev->dev_addr, addr->sa_data, ETH_ALEN);
// dev_ifsioc_locked()
memcpy(ifr->ifr_hwaddr.sa_data,
dev->dev_addr,...);

Close this race condition by guarding them with a RW semaphore,
like netdev_get_name(). We can not use seqlock here as it does not
allow blocking. The writers already take RTNL anyway, so this does
not affect the slow path. To avoid bothering existing
dev_set_mac_address() callers in drivers, introduce a new wrapper
just for user-facing callers on ioctl and rtnetlink paths.

Note, bonding also changes slave mac addresses but that requires
a separate patch due to the complexity of bonding code.

Fixes: 3710becf8a58 ("net: RCU locking for simple ioctl()")
Reported-by: "Gong, Sishuai" <sishuai@purdue.edu>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Cong Wang <cong.wang@bytedance.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dev_ioctl: remove redundant initialization of variable err

The variable err is being initialized with a value that is never read
and it is being updated later with a new value. The initialization is
redundant and can be removed.

Addresses-Coverity: ("Unused value")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Link: https://lore.kernel.org/r/20201102121615.695196-1-colin.king@canonical.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

treewide: Use fallthrough pseudo-keyword

Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

[1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>

net: Call into DSA netdevice_ops wrappers

Make the core net_device code call into our ndo_do_ioctl() and
ndo_get_phys_port_name() functions via the wrappers defined previously

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: Wrap ndo_do_ioctl() to prepare for DSA stacked ops

In preparation for adding another layer of call into a DSA stacked ops
singleton, wrap the ndo_do_ioctl() call into dev_do_ioctl().

Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ethtool: add timestamping related string sets

Add three string sets related to timestamping information:

ETH_SS_SOF_TIMESTAMPING: SOF_TIMESTAMPING_* flags
ETH_SS_TS_TX_TYPES: timestamping Tx types
ETH_SS_TS_RX_FILTERS: timestamping Rx filters

These will be used for TIMESTAMP_GET request.

v2: avoid compiler warning ("enumeration value not handled in switch")
in net_hwtstamp_validate()

v3: omit dash in Tx type names ("one-step-*" -> "onestep-*"), suggested by
Richard Cochran

Signed-off-by: Michal Kubecek <mkubecek@suse.cz>
Acked-by: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: Introduce peer to peer one step PTP time stamping.

The 1588 standard defines one step operation for both Sync and
PDelay_Resp messages. Up until now, hardware with P2P one step has
been rare, and kernel support was lacking. This patch adds support of
the mode in anticipation of new hardware developments.

Signed-off-by: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/core: Document all dev_ioctl() arguments

This patch avoids that the following warnings are reported when building
with W=1:

net/core/dev_ioctl.c:378: warning: Function parameter or member 'ifr' not described in 'dev_ioctl'
net/core/dev_ioctl.c:378: warning: Function parameter or member 'need_copyout' not described in 'dev_ioctl'
net/core/dev_ioctl.c:378: warning: Excess function parameter 'arg' description in 'dev_ioctl'

Cc: Al Viro <viro@zeniv.linux.org.uk>
Fixes: 44c02a2c3dc5 ("dev_ioctl(): move copyin/copyout to callers") # v4.16.
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dev: Add extack argument to dev_set_mac_address()

A follow-up patch will add a notifier type NETDEV_PRE_CHANGEADDR, which
allows vetoing of MAC address changes. One prominent path to that
notification is through dev_set_mac_address(). Therefore give this
function an extack argument, so that it can be packed together with the
notification. Thus a textual reason for rejection (or a warning) can be
communicated back to the user.

Signed-off-by: Petr Machata <petrm@mellanox.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: core: dev: Add extack argument to dev_change_flags()

In order to pass extack together with NETDEV_PRE_UP notifications, it's
necessary to route the extack to __dev_open() from diverse (possibly
indirect) callers. One prominent API through which the notification is
invoked is dev_change_flags().

Therefore extend dev_change_flags() with and extra extack argument and
update all users. Most of the calls end up just encoding NULL, but
several sites (VLAN, ipvlan, VRF, rtnetlink) do have extack available.

Since the function declaration line is changed anyway, name the other
function arguments to placate checkpatch.

Signed-off-by: Petr Machata <petrm@mellanox.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: remove redundant input checks in SIOCSIFTXQLEN case of dev_ifsioc

The cited patch added a call to dev_change_tx_queue_len in
SIOCSIFTXQLEN case.
This obsoletes the new len comparison check done before the function call.
Remove it here.

For the desicion of keep/remove the negative value check, we examine the
range check in dev_change_tx_queue_len.
On 64-bit we will fail with -ERANGE. The 32-bit int ifr_qlen will be sign
extended to 64-bits when it is passed into dev_change_tx_queue_len(). And
then for negative values this test triggers:

if (new_len != (unsigned int)new_len)
return -ERANGE;

because:
if (0xffffffffWHATEVER != 0x00000000WHATEVER)

On 32-bit the signed value will be accepted, changing behavior.

Therefore, the negative value check is kept.

Fixes: 3f76df198288 ("net: use dev_change_tx_queue_len() for SIOCSIFTXQLEN")
Signed-off-by: Tariq Toukan <tariqt@mellanox.com>
Reviewed-by: Eran Ben Elisha <eranbe@mellanox.com>
Cc: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: use dev_change_tx_queue_len() for SIOCSIFTXQLEN

As noticed by Eric, we need to switch to the helper
dev_change_tx_queue_len() for SIOCSIFTXQLEN call path too,
otheriwse still miss dev_qdisc_change_tx_queue_len().

Fixes: 6a643ddb5624 ("net: introduce helper dev_change_tx_queue_len()")
Reported-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: don't unnecessarily load kernel modules in dev_ioctl()

Starting with v4.16-rc1 we've been seeing a higher than usual number
of requests for the kernel to load networking modules, even on events
which shouldn't trigger a module load (e.g. ioctl(TCGETS)). Stephen
Smalley suggested the problem may lie in commit 44c02a2c3dc5
("dev_ioctl(): move copyin/copyout to callers") which moves changes
the network dev_ioctl() function to always call dev_load(),
regardless of the requested ioctl.

This patch moves the dev_load() calls back into the individual ioctls
while preserving the rest of the original patch.

Reported-by: Dominick Grift <dac.override@gmail.com>
Suggested-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

dev_ioctl(): move copyin/copyout to callers

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

lift handling of SIOCIW... out of dev_ioctl()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

net: separate SIOCGIFCONF handling from dev_ioctl()

Only two of dev_ioctl() callers may pass SIOCGIFCONF to it.
Separating that codepath from the rest of dev_ioctl() allows both
to simplify dev_ioctl() itself (all other cases work with struct ifreq *)
*and* seriously simplify the compat side of that beast: all it takes
is passing to inet_gifconf() an extra argument - the size of individual
records (sizeof(struct ifreq) or sizeof(struct compat_ifreq)). With
dev_ifconf() called directly from sock_do_ioctl()/compat_dev_ifconf()
that's easy to arrange.

As the result, compat side of SIOCGIFCONF doesn't need any
allocations, copy_in_user() back and forth, etc.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier. The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne. Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed. Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained >5
lines of source
- File already had some variant of a license header in it (even if <5
lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

- when both scanners couldn't find any license traces, file was
considered to have no license information in it, and the top level
COPYING file license applied.

For non */uapi/* files that summary was:

SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 11139

and resulted in the first patch in this series.

If that file was a */uapi/* path one, it was "GPL-2.0 WITH
Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was:

SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 WITH Linux-syscall-note 930

and resulted in the second patch in this series.

- if a file had some form of licensing information in it, and was one
of the */uapi/* ones, it was denoted with the Linux-syscall-note if
any GPL family license was found in the file or had no licensing in
it (per prior point). Results summary:

SPDX license identifier # files
---------------------------------------------------|------
GPL-2.0 WITH Linux-syscall-note 270
GPL-2.0+ WITH Linux-syscall-note 169
((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21
((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17
LGPL-2.1+ WITH Linux-syscall-note 15
GPL-1.0+ WITH Linux-syscall-note 14
((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5
LGPL-2.0+ WITH Linux-syscall-note 4
LGPL-2.1 WITH Linux-syscall-note 3
((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3
((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1

and that resulted in the third patch in this series.

- when the two scanners agreed on the detected license(s), that became
the concluded license(s).

- when there was disagreement between the two scanners (one detected a
license but the other didn't, or they both detected different
licenses) a manual inspection of the file occurred.

- In most cases a manual inspection of the information in the file
resulted in a clear resolution of the license that should apply (and
which scanner probably needed to revisit its heuristics).

- When it was not immediately clear, the license identifier was
confirmed with lawyers working with the Linux Foundation.

- If there was any question as to the appropriate license identifier,
the file was flagged for further research and to be revisited later
in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights. The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
- a full scancode scan run, collecting the matched texts, detected
license ids and scores
- reviewing anything where there was a license detected (about 500+
files) to ensure that the applied SPDX license was correct
- reviewing anything where there was no detection but the patch license
was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
SPDX license was correct

This produced a worksheet with 20 files needing minor correction. This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg. Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected. This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.) Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

dev_ioctl: add missing NETDEV_CHANGE_TX_QUEUE_LEN event notification

When changing dev tx_queue_len via netlink or net-sysfs,
a NETDEV_CHANGE_TX_QUEUE_LEN event notification will be
called.

But dev_ioctl missed this event notification, which could
cause no userspace notification would be sent.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: check dev->addr_len for dev_set_mac_address()

Historically, dev_ifsioc() uses struct sockaddr as mac
address definition, this is why dev_set_mac_address()
accepts a struct sockaddr pointer as input but now we
have various types of mac addresse whose lengths
are up to MAX_ADDR_LEN, longer than struct sockaddr,
and saved in dev->addr_len.

It is too late to fix dev_ifsioc() due to API
compatibility, so just reject those larger than
sizeof(struct sockaddr), otherwise we would read
and use some random bytes from kernel stack.

Fortunately, only a few IPv6 tunnel devices have addr_len
larger than sizeof(struct sockaddr) and they don't support
ndo_set_mac_addr(). But with team driver, in lb mode, they
can still be enslaved to a team master and make its mac addr
length as the same.

Cc: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: Zero terminate ifr_name in dev_ifname().

The ifr.ifr_name is passed around and assumed to be NULL terminated.

Signed-off-by: David S. Miller <davem@davemloft.net>

wireless: wext: terminate ifr name coming from userspace

ifr name is assumed to be a valid string by the kernel, but nothing
was forcing username to pass a valid string.

In turn, this would cause panics as we tried to access the string
past it's valid memory.

Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

dev_ioctl: copy only the smaller struct iwreq for wext

Unfortunately, struct iwreq isn't a proper subset of struct ifreq,
but is still handled by the same code path. Robert reported that
then applications may (randomly) fault if the struct iwreq they
pass happens to land within 8 bytes of the end of a mapping (the
struct is only 32 bytes, vs. struct ifreq's 40 bytes).

To fix this, pull out the code handling wireless extension ioctls
and copy only the smaller structure in this case.

This bug goes back a long time, I tracked that it was introduced
into mainline in 2.1.15, over 20 years ago!

This fixes https://bugzilla.kernel.org/show_bug.cgi?id=195869

Reported-by: Robert O'Callahan <robert@ocallahan.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

net: ethernet: update drivers to handle HWTSTAMP_FILTER_NTP_ALL

Include HWTSTAMP_FILTER_NTP_ALL in net_hwtstamp_validate() as a valid
filter and update drivers which can timestamp all packets, or which
explicitly list unsupported filters instead of using a default case, to
handle the filter.

CC: Richard Cochran <richardcochran@gmail.com>
CC: Willem de Bruijn <willemb@google.com>
Signed-off-by: Miroslav Lichvar <mlichvar@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: define receive timestamp filter for NTP

Add HWTSTAMP_FILTER_NTP_ALL to the hwtstamp_rx_filters enum for
timestamping of NTP packets. There is currently only one driver
(phyter) that could support it directly.

CC: Richard Cochran <richardcochran@gmail.com>
CC: Willem de Bruijn <willemb@google.com>
Signed-off-by: Miroslav Lichvar <mlichvar@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

dev_ioctl: use sizeof(x) instead of sizeof x

Also remove spaces after cast.

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: David S. Miller <davem@davemloft.net>

dev_ioctl: remove dev_load() CAP_SYS_MODULE message

Marcel reported to see the following message when autoloading
is being triggered when adding nlmon device:

Loading kernel module for a network device with
CAP_SYS_MODULE (deprecated). Use CAP_NET_ADMIN and alias
netdev-nlmon instead.

This false-positive happens despite with having correct
capabilities set, e.g. through issuing `ip link del dev nlmon`
more than once on a valid device with name nlmon, but Marcel
has also seen it on creation time when no nlmon module is
previously compiled-in or loaded as module and the device
name equals a link type name (e.g. nlmon, vxlan, team).

Stephen says:

The netdev module alias is a hold over from the past. For
normal devices, people used to create a alias eth0 to and
point it to the type of network device used, that was back
in the bad old ISA days before real discovery.

Also, the tunnels create module alias for the control device
and ip used to use this to autoload the tunnel device.

The message is bogus and should just be removed, I also see
it in a couple of other cases where tap devices are renamed
for other usese.

As mentioned in 8909c9ad8ff0 ("net: don't allow CAP_NET_ADMIN
to load non-netdev kernel modules"), we nevertheless still
might want to leave the old autoloading behaviour in place
as it could break old scripts, so for now, lets just remove
the log message as Stephen suggests.

Reference: http://thread.gmane.org/gmane.linux.kernel/1105168
Reported-by: Marcel Holtmann <marcel@holtmann.org>
Suggested-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Cc: Vasiliy Kulikov <segoon@openwall.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net_tstamp: Add SIOCGHWTSTAMP ioctl to match SIOCSHWTSTAMP

SIOCSHWTSTAMP returns the real configuration to the application
using it, but there is currently no way for any other
application to find out the configuration non-destructively.
Add a new ioctl for this, making it unprivileged.

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>

net: fix kernel deadlock with interface rename and netdev name retrieval.

When the kernel (compiled with CONFIG_PREEMPT=n) is performing the
rename of a network interface, it can end up waiting for a workqueue
to complete. If userland is able to invoke a SIOCGIFNAME ioctl or a
SO_BINDTODEVICE getsockopt in between, the kernel will deadlock due to
the fact that read_secklock_begin() will spin forever waiting for the
writer process (the one doing the interface rename) to update the
devnet_rename_seq sequence.

This patch fixes the problem by adding a helper (netdev_get_name())
and using it in the code handling the SIOCGIFNAME ioctl and
SO_BINDTODEVICE setsockopt.

The netdev_get_name() helper uses raw_seqcount_begin() to avoid
spinning forever, waiting for devnet_rename_seq->sequence to become
even. cond_resched() is used in the contended case, before retrying
the access to give the writer process a chance to finish.

The use of raw_seqcount_begin() will incur some unneeded work in the
reader process in the contended case, but this is better than
deadlocking the system.

Signed-off-by: Nicolas Schichan <nschichan@freebox.fr>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: move ioctl functions into a separated file

They well deserve a separated unit.

Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>