linux.git/net/ethtool/netlink.c, branch v6.14

net: ethtool: netlink: Allow NULL nlattrs when getting a phy_device

2025-03-05T01:12:01+00:00

ethnl_req_get_phydev() is used to lookup a phy_device, in the case an
ethtool netlink command targets a specific phydev within a netdev's
topology.

It takes as a parameter a const struct nlattr *header that's used for
error handling :

       if (!phydev) {
               NL_SET_ERR_MSG_ATTR(extack, header,
                                   "no phy matching phyindex");
               return ERR_PTR(-ENODEV);
       }

In the notify path after a ->set operation however, there's no request
attributes available.

The typical callsite for the above function looks like:

	phydev = ethnl_req_get_phydev(req_base, tb[ETHTOOL_A_XXX_HEADER],
				      info->extack);

So, when tb is NULL (such as in the ethnl notify path), we have a nice
crash.

It turns out that there's only the PLCA command that is in that case, as
the other phydev-specific commands don't have a notification.

This commit fixes the crash by passing the cmd index and the nlattr
array separately, allowing NULL-checking it directly inside the helper.

Fixes: c15e065b46dc ("net: ethtool: Allow passing a phy index for some commands")
Signed-off-by: Maxime Chevallier 
Reviewed-by: Kory Maincent 
Reported-by: Parthiban Veerasooran 
Link: https://patch.msgid.link/20250301141114.97204-1-maxime.chevallier@bootlin.com
Signed-off-by: Jakub Kicinski

Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

2025-01-21T09:24:33+00:00

No conflicts and no adjacent changes.

Signed-off-by: Paolo Abeni

net: provide pending ring configuration in net_device

2025-01-20T19:44:57+00:00

Record the pending configuration in net_device struct.
ethtool core duplicates the current config and the specific
handlers (for now just ringparam) can modify it.

Reviewed-by: Michael Chan 
Link: https://patch.msgid.link/20250119020518.1962249-4-kuba@kernel.org
Signed-off-by: Jakub Kicinski

net: ethtool: store netdev in a temp variable in ethnl_default_set_doit()

2025-01-20T19:44:57+00:00

For ease of review of the next patch store the dev pointer
on the stack, instead of referring to req_info.dev every time.

No functional changes.

Reviewed-by: Michael Chan 
Link: https://patch.msgid.link/20250119020518.1962249-3-kuba@kernel.org
Signed-off-by: Jakub Kicinski

net: avoid race between device unregistration and ethnl ops

2025-01-19T01:37:31+00:00

The following trace can be seen if a device is being unregistered while
its number of channels are being modified.

  DEBUG_LOCKS_WARN_ON(lock->magic != lock)
  WARNING: CPU: 3 PID: 3754 at kernel/locking/mutex.c:564 __mutex_lock+0xc8a/0x1120
  CPU: 3 UID: 0 PID: 3754 Comm: ethtool Not tainted 6.13.0-rc6+ #771
  RIP: 0010:__mutex_lock+0xc8a/0x1120
  Call Trace:
   
   ethtool_check_max_channel+0x1ea/0x880
   ethnl_set_channels+0x3c3/0xb10
   ethnl_default_set_doit+0x306/0x650
   genl_family_rcv_msg_doit+0x1e3/0x2c0
   genl_rcv_msg+0x432/0x6f0
   netlink_rcv_skb+0x13d/0x3b0
   genl_rcv+0x28/0x40
   netlink_unicast+0x42e/0x720
   netlink_sendmsg+0x765/0xc20
   __sys_sendto+0x3ac/0x420
   __x64_sys_sendto+0xe0/0x1c0
   do_syscall_64+0x95/0x180
   entry_SYSCALL_64_after_hwframe+0x76/0x7e

This is because unregister_netdevice_many_notify might run before the
rtnl lock section of ethnl operations, eg. set_channels in the above
example. In this example the rss lock would be destroyed by the device
unregistration path before being used again, but in general running
ethnl operations while dismantle has started is not a good idea.

Fix this by denying any operation on devices being unregistered. A check
was already there in ethnl_ops_begin, but not wide enough.

Note that the same issue cannot be seen on the ioctl version
(__dev_ethtool) because the device reference is retrieved from within
the rtnl lock section there. Once dismantle started, the net device is
unlisted and no reference will be found.

Fixes: dde91ccfa25f ("ethtool: do not perform operations on net devices being unregistered")
Signed-off-by: Antoine Tenart 
Reviewed-by: Przemek Kitszel 
Reviewed-by: Edward Cree 
Link: https://patch.msgid.link/20250116092159.50890-1-atenart@kernel.org
Signed-off-by: Jakub Kicinski

net: ethtool: Add support for tsconfig command to get/set hwtstamp config

2024-12-16T12:51:41+00:00

Introduce support for ETHTOOL_MSG_TSCONFIG_GET/SET ethtool netlink socket
to read and configure hwtstamp configuration of a PHC provider. Note that
simultaneous hwtstamp isn't supported; configuring a new one disables the
previous setting.

Signed-off-by: Kory Maincent 
Signed-off-by: David S. Miller

net: ethtool: tsinfo: Enhance tsinfo to support several hwtstamp by net topology

2024-12-16T12:51:41+00:00

Either the MAC or the PHY can provide hwtstamp, so we should be able to
read the tsinfo for any hwtstamp provider.

Enhance 'get' command to retrieve tsinfo of hwtstamp providers within a
network topology.

Add support for a specific dump command to retrieve all hwtstamp
providers within the network topology, with added functionality for
filtered dump to target a single interface.

Signed-off-by: Kory Maincent 
Signed-off-by: David S. Miller

net: ethtool: Introduce a command to list PHYs on an interface

2024-08-23T12:04:34+00:00

As we have the ability to track the PHYs connected to a net_device
through the link_topology, we can expose this list to userspace. This
allows userspace to use these identifiers for phy-specific commands and
take the decision of which PHY to target by knowing the link topology.

Add PHY_GET and PHY_DUMP, which can be a filtered DUMP operation to list
devices on only one interface.

Signed-off-by: Maxime Chevallier 
Reviewed-by: Christophe Leroy 
Tested-by: Christophe Leroy 
Signed-off-by: David S. Miller

net: ethtool: Allow passing a phy index for some commands

2024-08-23T12:04:34+00:00

Some netlink commands are target towards ethernet PHYs, to control some
of their features. As there's several such commands, add the ability to
pass a PHY index in the ethnl request, which will populate the generic
ethnl_req_info with the passed phy_index.

Add a helper that netlink command handlers need to use to grab the
targeted PHY from the req_info. This helper needs to hold rtnl_lock()
while interacting with the PHY, as it may be removed at any point.

Signed-off-by: Maxime Chevallier 
Reviewed-by: Christophe Leroy 
Tested-by: Christophe Leroy 
Signed-off-by: David S. Miller

ethtool: rss: support dumping RSS contexts

2024-08-12T13:16:24+00:00

Now that we track RSS contexts in the core we can easily dump
them. This is a major introspection improvement, as previously
the only way to find all contexts would be to try all ids
(of which there may be 2^32 - 1).

Don't use the XArray iterators (like xa_for_each_start()) as they
do not move the index past the end of the array once done, which
caused multiple bugs in Netlink dumps in the past.

Reviewed-by: Edward Cree 
Reviewed-by: Joe Damato 
Signed-off-by: Jakub Kicinski 
Signed-off-by: David S. Miller