linux.git/net/ethtool, branch v6.18.21 Clone of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git net: rss: fix reporting RXH_XFRM_NO_CHANGE as input_xfrm for contexts 2026-02-11T12:41:57+00:00 Jakub Kicinski kuba@kernel.org 2026-01-30T19:03:11+00:00 f3931416cbdd043e83d50198e7e740f205211672 [ Upstream commit 1c172febdf065375359b2b95156e476bfee30b60 ] Initializing input_xfrm to RXH_XFRM_NO_CHANGE in RSS contexts is problematic. I think I did this to make it clear that the context does not have its own settings applied. But unlike ETH_RSS_HASH_NO_CHANGE which is zero, RXH_XFRM_NO_CHANGE is 0xff. We need to be careful when reading the value back, and remember to treat 0xff as 0. Remove the initialization and switch to storing 0. This lets us also remove the workaround in ethnl_rss_set(). Get side does not need any adjustments and context get no longer reports: RSS input transformation: symmetric-xor: on symmetric-or-xor: on Unknown bits in RSS input transformation: 0xfc for NICs which don't support input_xfrm. Remove the init of hfunc to ETH_RSS_HASH_NO_CHANGE while at it. As already mentioned this is a noop since ETH_RSS_HASH_NO_CHANGE is 0 and struct is zalloc'd. But as this fix exemplifies storing NO_CHANGE as state is fragile. This issue is implicitly caught by running our selftests because YNL in selftests errors out on unknown bits. Fixes: d3e2c7bab124 ("ethtool: rss: support setting input-xfrm via Netlink") Link: https://patch.msgid.link/20260130190311.811129-1-kuba@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 1c172febdf065375359b2b95156e476bfee30b60 ]

Initializing input_xfrm to RXH_XFRM_NO_CHANGE in RSS contexts is
problematic. I think I did this to make it clear that the context
does not have its own settings applied. But unlike ETH_RSS_HASH_NO_CHANGE
which is zero, RXH_XFRM_NO_CHANGE is 0xff. We need to be careful
when reading the value back, and remember to treat 0xff as 0.

Remove the initialization and switch to storing 0. This lets us
also remove the workaround in ethnl_rss_set(). Get side does not
need any adjustments and context get no longer reports:

  RSS input transformation:
    symmetric-xor: on
    symmetric-or-xor: on
    Unknown bits in RSS input transformation: 0xfc

for NICs which don't support input_xfrm.

Remove the init of hfunc to ETH_RSS_HASH_NO_CHANGE while at it.
As already mentioned this is a noop since ETH_RSS_HASH_NO_CHANGE
is 0 and struct is zalloc'd. But as this fix exemplifies storing
NO_CHANGE as state is fragile.

This issue is implicitly caught by running our selftests because
YNL in selftests errors out on unknown bits.

Fixes: d3e2c7bab124 ("ethtool: rss: support setting input-xfrm via Netlink")
Link: https://patch.msgid.link/20260130190311.811129-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
ethtool: Avoid overflowing userspace buffer on stats query 2026-01-02T11:56:48+00:00 Gal Pressman gal@nvidia.com 2025-12-08T12:19:01+00:00 4066b5b546293f44cd6d0e84ece6e3ee7ff27093 [ Upstream commit 7b07be1ff1cb6c49869910518650e8d0abc7d25f ] The ethtool -S command operates across three ioctl calls: ETHTOOL_GSSET_INFO for the size, ETHTOOL_GSTRINGS for the names, and ETHTOOL_GSTATS for the values. If the number of stats changes between these calls (e.g., due to device reconfiguration), userspace's buffer allocation will be incorrect, potentially leading to buffer overflow. Drivers are generally expected to maintain stable stat counts, but some drivers (e.g., mlx5, bnx2x, bna, ksz884x) use dynamic counters, making this scenario possible. Some drivers try to handle this internally: - bnad_get_ethtool_stats() returns early in case stats.n_stats is not equal to the driver's stats count. - micrel/ksz884x also makes sure not to write anything beyond stats.n_stats and overflow the buffer. However, both use stats.n_stats which is already assigned with the value returned from get_sset_count(), hence won't solve the issue described here. Change ethtool_get_strings(), ethtool_get_stats(), ethtool_get_phy_stats() to not return anything in case of a mismatch between userspace's size and get_sset_size(), to prevent buffer overflow. The returned n_stats value will be equal to zero, to reflect that nothing has been returned. This could result in one of two cases when using upstream ethtool, depending on when the size change is detected: 1. When detected in ethtool_get_strings(): # ethtool -S eth2 no stats available 2. When detected in get stats, all stats will be reported as zero. Both cases are presumably transient, and a subsequent ethtool call should succeed. Other than the overflow avoidance, these two cases are very evident (no output/cleared stats), which is arguably better than presenting incorrect/shifted stats. I also considered returning an error instead of a "silent" response, but that seems more destructive towards userspace apps. Notes: - This patch does not claim to fix the inherent race, it only makes sure that we do not overflow the userspace buffer, and makes for a more predictable behavior. - RTNL lock is held during each ioctl, the race window exists between the separate ioctl calls when the lock is released. - Userspace ethtool always fills stats.n_stats, but it is likely that these stats ioctls are implemented in other userspace applications which might not fill it. The added code checks that it's not zero, to prevent any regressions. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Reviewed-by: Dragos Tatulea <dtatulea@nvidia.com> Reviewed-by: Tariq Toukan <tariqt@nvidia.com> Signed-off-by: Gal Pressman <gal@nvidia.com> Link: https://patch.msgid.link/20251208121901.3203692-1-gal@nvidia.com Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 7b07be1ff1cb6c49869910518650e8d0abc7d25f ]

The ethtool -S command operates across three ioctl calls:
ETHTOOL_GSSET_INFO for the size, ETHTOOL_GSTRINGS for the names, and
ETHTOOL_GSTATS for the values.

If the number of stats changes between these calls (e.g., due to device
reconfiguration), userspace's buffer allocation will be incorrect,
potentially leading to buffer overflow.

Drivers are generally expected to maintain stable stat counts, but some
drivers (e.g., mlx5, bnx2x, bna, ksz884x) use dynamic counters, making
this scenario possible.

Some drivers try to handle this internally:
- bnad_get_ethtool_stats() returns early in case stats.n_stats is not
  equal to the driver's stats count.
- micrel/ksz884x also makes sure not to write anything beyond
  stats.n_stats and overflow the buffer.

However, both use stats.n_stats which is already assigned with the value
returned from get_sset_count(), hence won't solve the issue described
here.

Change ethtool_get_strings(), ethtool_get_stats(),
ethtool_get_phy_stats() to not return anything in case of a mismatch
between userspace's size and get_sset_size(), to prevent buffer
overflow.
The returned n_stats value will be equal to zero, to reflect that
nothing has been returned.

This could result in one of two cases when using upstream ethtool,
depending on when the size change is detected:
1. When detected in ethtool_get_strings():
    # ethtool -S eth2
    no stats available

2. When detected in get stats, all stats will be reported as zero.

Both cases are presumably transient, and a subsequent ethtool call
should succeed.

Other than the overflow avoidance, these two cases are very evident (no
output/cleared stats), which is arguably better than presenting
incorrect/shifted stats.
I also considered returning an error instead of a "silent" response, but
that seems more destructive towards userspace apps.

Notes:
- This patch does not claim to fix the inherent race, it only makes sure
  that we do not overflow the userspace buffer, and makes for a more
  predictable behavior.

- RTNL lock is held during each ioctl, the race window exists between
  the separate ioctl calls when the lock is released.

- Userspace ethtool always fills stats.n_stats, but it is likely that
  these stats ioctls are implemented in other userspace applications
  which might not fill it. The added code checks that it's not zero,
  to prevent any regressions.

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Reviewed-by: Dragos Tatulea <dtatulea@nvidia.com>
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: Gal Pressman <gal@nvidia.com>
Link: https://patch.msgid.link/20251208121901.3203692-1-gal@nvidia.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Revert "Documentation: net: add flow control guide and document ethtool API" 2025-10-01T07:48:21+00:00 Paolo Abeni pabeni@redhat.com 2025-09-30T13:45:06+00:00 1a98f5699bd57c9b3f66ec54cc38571d5e42ffb1 This reverts commit 7bd80ed89d72285515db673803b021469ba71ee8. I should not have merged it to begin with due to pending review and changes to be addressed. Link: https://patch.msgid.link/c6f3af12df9b7998920a02027fc8893ce82afc4c.1759239721.git.pabeni@redhat.com Signed-off-by: Paolo Abeni <pabeni@redhat.com> 
This reverts commit 7bd80ed89d72285515db673803b021469ba71ee8.

I should not have merged it to begin with due to pending review and
changes to be addressed.

Link: https://patch.msgid.link/c6f3af12df9b7998920a02027fc8893ce82afc4c.1759239721.git.pabeni@redhat.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Documentation: net: add flow control guide and document ethtool API 2025-09-30T07:48:31+00:00 Oleksij Rempel o.rempel@pengutronix.de 2025-09-24T12:02:41+00:00 7bd80ed89d72285515db673803b021469ba71ee8 Introduce a new document, flow_control.rst, to provide a comprehensive guide on Ethernet Flow Control in Linux. The guide explains how flow control works, how autonegotiation resolves pause capabilities, and how to configure it using ethtool and Netlink. In parallel, document the pause and pause-stat attributes in the ethtool.yaml netlink spec. This enables the ynl tool to generate kernel-doc comments for the corresponding enums in the UAPI header, making the C interface self-documenting. Finally, replace the legacy flow control section in phy.rst with a reference to the new document and add pointers in the relevant C source files. Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de> Link: https://patch.msgid.link/20250924120241.724850-1-o.rempel@pengutronix.de Signed-off-by: Paolo Abeni <pabeni@redhat.com> 
Introduce a new document, flow_control.rst, to provide a comprehensive
guide on Ethernet Flow Control in Linux. The guide explains how flow
control works, how autonegotiation resolves pause capabilities, and how
to configure it using ethtool and Netlink.

In parallel, document the pause and pause-stat attributes in the
ethtool.yaml netlink spec. This enables the ynl tool to generate
kernel-doc comments for the corresponding enums in the UAPI header,
making the C interface self-documenting.

Finally, replace the legacy flow control section in phy.rst with a
reference to the new document and add pointers in the relevant C source
files.

Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Link: https://patch.msgid.link/20250924120241.724850-1-o.rempel@pengutronix.de
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
net: ethtool: remove duplicated mm.o from Makefile 2025-09-29T19:09:24+00:00 Markus Heidelberg m.heidelberg@cab.de 2025-09-26T13:13:23+00:00 2804359536275d8d5f92eb1949102eca4153ea1e Fixes: 2b30f8291a30 ("net: ethtool: add support for MAC Merge layer") Signed-off-by: Markus Heidelberg <m.heidelberg@cab.de> Reviewed-by: Vladimir Oltean <vladimir.oltean@nxp.com> Link: https://patch.msgid.link/20250926131323.222192-1-m.heidelberg@cab.de Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
Fixes: 2b30f8291a30 ("net: ethtool: add support for MAC Merge layer")
Signed-off-by: Markus Heidelberg <m.heidelberg@cab.de>
Reviewed-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Link: https://patch.msgid.link/20250926131323.222192-1-m.heidelberg@cab.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
ethtool: add FEC bins histogram report 2025-09-26T23:49:18+00:00 Vadim Fedorenko vadim.fedorenko@linux.dev 2025-09-24T12:40:33+00:00 cc2f08129925b437bf28f7f7822f20dac083a87c IEEE 802.3ck-2022 defines counters for FEC bins and 802.3df-2024 clarifies it a bit further. Implement reporting interface through as addition to FEC stats available in ethtool. Drivers can leave bin counter uninitialized if per-lane values are provided. In this case the core will recalculate summ for the bin. Signed-off-by: Vadim Fedorenko <vadim.fedorenko@linux.dev> Reviewed-by: Aleksandr Loktionov <aleksandr.loktionov@intel.com> Link: https://patch.msgid.link/20250924124037.1508846-2-vadim.fedorenko@linux.dev Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
IEEE 802.3ck-2022 defines counters for FEC bins and 802.3df-2024
clarifies it a bit further. Implement reporting interface through as
addition to FEC stats available in ethtool. Drivers can leave bin
counter uninitialized if per-lane values are provided. In this case the
core will recalculate summ for the bin.

Signed-off-by: Vadim Fedorenko <vadim.fedorenko@linux.dev>
Reviewed-by: Aleksandr Loktionov <aleksandr.loktionov@intel.com>
Link: https://patch.msgid.link/20250924124037.1508846-2-vadim.fedorenko@linux.dev
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
net: ethtool: tsconfig: set command must provide a reply 2025-09-24T00:13:05+00:00 Vadim Fedorenko vadfed@meta.com 2025-09-22T23:19:24+00:00 e8ab231782e92bc26e5eb605263525636a2f7ae7 Timestamping configuration through ethtool has inconsistent behavior of skipping the reply for set command if configuration was not changed. Fix it be providing reply in any case. Fixes: 6e9e2eed4f39d ("net: ethtool: Add support for tsconfig command to get/set hwtstamp config") Signed-off-by: Vadim Fedorenko <vadfed@meta.com> Reviewed-by: Kory Maincent <kory.maincent@bootlin.com> Link: https://patch.msgid.link/20250922231924.2769571-1-vadfed@meta.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
Timestamping configuration through ethtool has inconsistent behavior of
skipping the reply for set command if configuration was not changed. Fix
it be providing reply in any case.

Fixes: 6e9e2eed4f39d ("net: ethtool: Add support for tsconfig command to get/set hwtstamp config")
Signed-off-by: Vadim Fedorenko <vadfed@meta.com>
Reviewed-by: Kory Maincent <kory.maincent@bootlin.com>
Link: https://patch.msgid.link/20250922231924.2769571-1-vadfed@meta.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2025-09-18T18:26:06+00:00 Jakub Kicinski kuba@kernel.org 2025-09-18T18:23:29+00:00 f2cdc4c22bca57ab4cdb28ef4a02c53837d26fe0 Cross-merge networking fixes after downstream PR (net-6.17-rc7). No conflicts. Adjacent changes: drivers/net/ethernet/mellanox/mlx5/core/en/fs.h 9536fbe10c9d ("net/mlx5e: Add PSP steering in local NIC RX") 7601a0a46216 ("net/mlx5e: Add a miss level for ipsec crypto offload") Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
Cross-merge networking fixes after downstream PR (net-6.17-rc7).

No conflicts.

Adjacent changes:

drivers/net/ethernet/mellanox/mlx5/core/en/fs.h
  9536fbe10c9d ("net/mlx5e: Add PSP steering in local NIC RX")
  7601a0a46216 ("net/mlx5e: Add a miss level for ipsec crypto offload")

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
net: ethtool: use the new helper in rss_set_prep_indir() 2025-09-18T14:07:38+00:00 Breno Leitao leitao@debian.org 2025-09-17T09:58:14+00:00 8b7c4b612decb79b157611225faee68c384102a9 Refactor rss_set_prep_indir() to utilize the new ethtool_get_rx_ring_count() helper for determining the number of RX rings, replacing the direct use of get_rxnfc with ETHTOOL_GRXRINGS. This ensures compatibility with both legacy and new ethtool_ops interfaces by transparently multiplexing between them. Signed-off-by: Breno Leitao <leitao@debian.org> Link: https://patch.msgid.link/20250917-gxrings-v4-7-dae520e2e1cb@debian.org Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
Refactor rss_set_prep_indir() to utilize the new
ethtool_get_rx_ring_count() helper for determining the number of RX
rings, replacing the direct use of get_rxnfc with ETHTOOL_GRXRINGS.

This ensures compatibility with both legacy and new ethtool_ops
interfaces by transparently multiplexing between them.

Signed-off-by: Breno Leitao <leitao@debian.org>
Link: https://patch.msgid.link/20250917-gxrings-v4-7-dae520e2e1cb@debian.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
net: ethtool: update set_rxfh_indir to use ethtool_get_rx_ring_count helper 2025-09-18T14:07:38+00:00 Breno Leitao leitao@debian.org 2025-09-17T09:58:13+00:00 dce08107f1f305b0fbef115410034b1fb3b7e070 Modify ethtool_set_rxfh() to use the new ethtool_get_rx_ring_count() helper function for retrieving the number of RX rings instead of directly calling get_rxnfc with ETHTOOL_GRXRINGS. This way, we can leverage the new helper if it is available in ethtool_ops. Signed-off-by: Breno Leitao <leitao@debian.org> Link: https://patch.msgid.link/20250917-gxrings-v4-6-dae520e2e1cb@debian.org Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
Modify ethtool_set_rxfh() to use the new ethtool_get_rx_ring_count()
helper function for retrieving the number of RX rings instead of
directly calling get_rxnfc with ETHTOOL_GRXRINGS.

This way, we can leverage the new helper if it is available in ethtool_ops.

Signed-off-by: Breno Leitao <leitao@debian.org>
Link: https://patch.msgid.link/20250917-gxrings-v4-6-dae520e2e1cb@debian.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>