linux.git/net/ethtool/pause.c, branch v7.1-rc4

net: ethtool: pass genl_info to the ethnl parse_request operation

2026-03-25T03:14:29+00:00

The .parse_request() ethnl operation extracts the relevant attributes
from the netlink request to populate the private req_info.

By passing genl_info as a parameter to this callback, we can use
the GENL_REQ_ATTR_CHECK() macro to check for missing mandatory
parameters.

This macro has the advantage of returning a better error explanation
through the netlink_ext_ack struct.

Convert the eeprom ethnl code to this macro, as it's the only command
yet that has mandatory request parameters.

Suggested-by: Jakub Kicinski 
Signed-off-by: Maxime Chevallier 
Link: https://patch.msgid.link/20260323095833.136266-1-maxime.chevallier@bootlin.com
Signed-off-by: Jakub Kicinski

net: ethtool: re-order local includes

2026-03-21T02:10:18+00:00

Most local #include in the ethtool command handling is out of order,
with either :

 #include "netlink.h"
 #include "common.h"

or even :

 #include "netlink.h"
 #include "common.h"
 #include "bitset.h"

One of the reasons is because bitset.h s lacking definitions for
nlattr, netlink_ext_ack, ETH_GSTRING_LEN, and types such as u32, bool,
etc.

Make bitset.h standalone by including  for
ETH_GSTRING_LEN, and  for nlattr, netlink_ext_ack and
the rest.

While at it, take a pass on ethnl sources to re-order the local
includes :
 - put them after the global includes
 - add a newline between global and local includes
 - alpha-sort the local includes

One notable exception is the cmis.h include, that needs definitions from
module_fw.h. Keep them in this order for now.

Signed-off-by: Maxime Chevallier 
Link: https://patch.msgid.link/20260319180555.1531386-1-maxime.chevallier@bootlin.com
Signed-off-by: Jakub Kicinski

net: ethtool: Track pause storm events

2026-03-05T15:26:52+00:00

With TX pause enabled, if a device is unable to pass packets up to the
stack (e.g., CPU is hanged), the device can cause pause storm. Given
that devices can have native support to protect the neighbor from such
flooding, such events need some tracking. This support is to track TX
pause storm events for better observability.

Reviewed-by: Oleksij Rempel 
Signed-off-by: Jakub Kicinski 
Signed-off-by: Mohsin Bashir 
Link: https://patch.msgid.link/20260302230149.1580195-2-mohsin.bashr@gmail.com
Signed-off-by: Paolo Abeni

net: ethtool: avoid OOB accesses in PAUSE_SET

2025-06-30T15:32:37+00:00

We now reuse .parse_request() from GET on SET, so we need to make sure
that the policies for both cover the attributes used for .parse_request().
genetlink will only allocate space in info->attrs for ARRAY_SIZE(policy).

Reported-by: syzbot+430f9f76633641a62217@syzkaller.appspotmail.com
Fixes: 963781bdfe20 ("net: ethtool: call .parse_request for SET handlers")
Reviewed-by: Ido Schimmel 
Tested-by: Ido Schimmel 
Link: https://patch.msgid.link/20250626233926.199801-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski

ethtool: netlink: always pass genl_info to .prepare_data

2023-08-15T22:01:03+00:00

We had a number of bugs in the past because developers forgot
to fully test dumps, which pass NULL as info to .prepare_data.
.prepare_data implementations would try to access info->extack
leading to a null-deref.

Now that dumps and notifications can access struct genl_info
we can pass it in, and remove the info null checks.

Reviewed-by: Vladimir Oltean 
Tested-by: Vladimir Oltean  # pause
Reviewed-by: Jiri Pirko 
Link: https://lore.kernel.org/r/20230814214723.2924989-11-kuba@kernel.org
Signed-off-by: Jakub Kicinski

ethtool: netlink: handle SET intro/outro in the common code

2023-01-27T12:24:31+00:00

Most ethtool SET callbacks follow the same general structure.

  ethnl_parse_header_dev_get()
  rtnl_lock()
  ethnl_ops_begin()

  ... do stuff ...

  ethtool_notify()
  ethnl_ops_complete()
  rtnl_unlock()
  ethnl_parse_header_dev_put()

This leads to a lot of copy / pasted code an bugs when people
mis-handle the error path.

Add a generic implementation of this pattern with a .set callback
in struct ethnl_request_ops called to "do stuff".

Also add an optional .set_validate which is called before
ethnl_ops_begin() -- a lot of implementations do basic request
capability / sanity checking at that point.

Because we want to avoid generating the notification when
no change happened - adopt a slightly hairy return values:
 - 0 means nothing to do (no notification)
 - 1 means done / continue
 - negative error codes on error

Reuse .hdr_attr from struct ethnl_request_ops, GET and SET
use the same attr spaces in all cases.

Convert pause as an example (and to avoid unused function warnings).

Signed-off-by: Jakub Kicinski 
Signed-off-by: David S. Miller

net: ethtool: fix NULL pointer dereference in pause_prepare_data()

2023-01-25T09:57:41+00:00

In the following call path:

ethnl_default_dumpit
-> ethnl_default_dump_one
   -> ctx->ops->prepare_data
      -> pause_prepare_data

struct genl_info *info will be passed as NULL, and pause_prepare_data()
dereferences it while getting the extended ack pointer.

To avoid that, just set the extack to NULL if "info" is NULL, since the
netlink extack handling messages know how to deal with that.

The pattern "info ? info->extack : NULL" is present in quite a few other
"prepare_data" implementations, so it's clear that it's a more general
problem to be dealt with at a higher level, but the code should have at
least adhered to the current conventions to avoid the NULL dereference.

Fixes: 04692c9020b7 ("net: ethtool: netlink: retrieve stats from multiple sources (eMAC, pMAC)")
Reported-by: Eric Dumazet 
Signed-off-by: Vladimir Oltean 
Reported-by: syzbot+9d44aae2720fc40b8474@syzkaller.appspotmail.com
Signed-off-by: David S. Miller

net: ethtool: netlink: retrieve stats from multiple sources (eMAC, pMAC)

2023-01-23T12:44:18+00:00

IEEE 802.3-2018 clause 99 defines a MAC Merge sublayer which contains an
Express MAC and a Preemptible MAC. Both MACs are hidden to higher and
lower layers and visible as a single MAC (packet classification to eMAC
or pMAC on TX is done based on priority; classification on RX is done
based on SFD).

For devices which support a MAC Merge sublayer, it is desirable to
retrieve individual packet counters from the eMAC and the pMAC, as well
as aggregate statistics (their sum).

Introduce a new ETHTOOL_A_STATS_SRC attribute which is part of the
policy of ETHTOOL_MSG_STATS_GET and, and an ETHTOOL_A_PAUSE_STATS_SRC
which is part of the policy of ETHTOOL_MSG_PAUSE_GET (accepted when
ETHTOOL_FLAG_STATS is set in the common ethtool header). Both of these
take values from enum ethtool_mac_stats_src, defaulting to "aggregate"
in the absence of the attribute.

Existing drivers do not need to pay attention to this enum which was
added to all driver-facing structures, just the ones which report the
MAC merge layer as supported.

Signed-off-by: Vladimir Oltean 
Signed-off-by: David S. Miller

ethtool: use ethnl_parse_header_dev_put()

2021-12-15T10:27:47+00:00

It seems I missed that most ethnl_parse_header_dev_get() callers
declare an on-stack struct ethnl_req_info, and that they simply call
dev_put(req_info.dev) when about to return.

Add ethnl_parse_header_dev_put() helper to properly untrack
reference taken by ethnl_parse_header_dev_get().

Fixes: e4b8954074f6 ("netlink: add net device refcount tracker to struct ethnl_req_info")
Signed-off-by: Eric Dumazet 
Signed-off-by: David S. Miller

ethtool: fix ethtool msg len calculation for pause stats

2021-11-03T11:20:45+00:00

ETHTOOL_A_PAUSE_STAT_MAX is the MAX attribute id,
so we need to subtract non-stats and add one to
get a count (IOW -2+1 == -1).

Otherwise we'll see:

  ethnl cmd 21: calculated reply length 40, but consumed 52

Fixes: 9a27a33027f2 ("ethtool: add standard pause stats")
Signed-off-by: Jakub Kicinski 
Reviewed-by: Saeed Mahameed 
Signed-off-by: David S. Miller