kernel/linux.git/net/ethtool, branch v6.12.80

ethtool: Avoid overflowing userspace buffer on stats query

2026-01-08T09:14:02+00:00

[ 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 Reviewed-by: Tariq Toukan Signed-off-by: Gal Pressman Link: https://patch.msgid.link/20251208121901.3203692-1-gal@nvidia.com Signed-off-by: Paolo Abeni Signed-off-by: Sasha Levin

ethtool: cmis_cdb: use correct rpl size in ethtool_cmis_module_poll()

2025-04-25T08:47:43+00:00

[ Upstream commit f3fdd4fba16c74697d8bc730b82fb7c1eff7fab3 ] rpl is passed as a pointer to ethtool_cmis_module_poll(), so the correct size of rpl is sizeof(*rpl) which should be just 1 byte. Using the pointer size instead can cause stack corruption: Kernel panic - not syncing: stack-protector: Kernel stack is corrupted in: ethtool_cmis_wait_for_cond+0xf4/0x100 CPU: 72 UID: 0 PID: 4440 Comm: kworker/72:2 Kdump: loaded Tainted: G OE 6.11.0 #24 Tainted: [O]=OOT_MODULE, [E]=UNSIGNED_MODULE Hardware name: Dell Inc. PowerEdge R760/04GWWM, BIOS 1.6.6 09/20/2023 Workqueue: events module_flash_fw_work Call Trace: panic+0x339/0x360 ? ethtool_cmis_wait_for_cond+0xf4/0x100 ? __pfx_status_success+0x10/0x10 ? __pfx_status_fail+0x10/0x10 __stack_chk_fail+0x10/0x10 ethtool_cmis_wait_for_cond+0xf4/0x100 ethtool_cmis_cdb_execute_cmd+0x1fc/0x330 ? __pfx_status_fail+0x10/0x10 cmis_cdb_module_features_get+0x6d/0xd0 ethtool_cmis_cdb_init+0x8a/0xd0 ethtool_cmis_fw_update+0x46/0x1d0 module_flash_fw_work+0x17/0xa0 process_one_work+0x179/0x390 worker_thread+0x239/0x340 ? __pfx_worker_thread+0x10/0x10 kthread+0xcc/0x100 ? __pfx_kthread+0x10/0x10 ret_from_fork+0x2d/0x50 ? __pfx_kthread+0x10/0x10 ret_from_fork_asm+0x1a/0x30 Fixes: a39c84d79625 ("ethtool: cmis_cdb: Add a layer for supporting CDB commands") Reviewed-by: Andy Gospodarek Reviewed-by: Simon Horman Reviewed-by: Ido Schimmel Signed-off-by: Damodharam Ammepalli Signed-off-by: Michael Chan Link: https://patch.msgid.link/20250409173312.733012-1-michael.chan@broadcom.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

net: ethtool: Don't call .cleanup_data when prepare_data fails

2025-04-20T08:15:07+00:00

[ Upstream commit 4f038a6a02d20859a3479293cbf172b0f14cbdd6 ] There's a consistent pattern where the .cleanup_data() callback is called when .prepare_data() fails, when it should really be called to clean after a successful .prepare_data() as per the documentation. Rewrite the error-handling paths to make sure we don't cleanup un-prepared data. Fixes: c781ff12a2f3 ("ethtool: Allow network drivers to dump arbitrary EEPROM data") Reviewed-by: Kory Maincent Reviewed-by: Simon Horman Reviewed-by: Michal Kubecek Signed-off-by: Maxime Chevallier Link: https://patch.msgid.link/20250407130511.75621-1-maxime.chevallier@bootlin.com Signed-off-by: Paolo Abeni Signed-off-by: Sasha Levin

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

2025-03-13T12:02:08+00:00

[ Upstream commit 637399bf7e77797811adf340090b561a8f9d1213 ] 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 Signed-off-by: Sasha Levin

net: ethtool: plumb PHY stats to PHY drivers

2025-03-13T12:02:07+00:00

[ Upstream commit b7a2c1fe6b55364e61b4b54b991eb43a47bb1104 ] Introduce support for standardized PHY statistics reporting in ethtool by extending the PHYLIB framework. Add the functions phy_ethtool_get_phy_stats() and phy_ethtool_get_link_ext_stats() to provide a consistent interface for retrieving PHY-level and link-specific statistics. These functions are used within the ethtool implementation to avoid direct access to the phy_device structure outside of the PHYLIB framework. A new structure, ethtool_phy_stats, is introduced to standardize PHY statistics such as packet counts, byte counts, and error counters. Drivers are updated to include callbacks for retrieving PHY and link-specific statistics, ensuring values are explicitly set only for supported fields, initialized with ETHTOOL_STAT_NOT_SET to avoid ambiguity. Signed-off-by: Jakub Kicinski Signed-off-by: Oleksij Rempel Signed-off-by: Paolo Abeni Stable-dep-of: 637399bf7e77 ("net: ethtool: netlink: Allow NULL nlattrs when getting a phy_device") Signed-off-by: Sasha Levin

ethtool: linkstate: migrate linkstate functions to support multi-PHY setups

2025-03-13T12:02:07+00:00

[ Upstream commit fe55b1d401c697c2ef126fe3ebbcaa6885fced5a ] Adapt linkstate_get_sqi() and linkstate_get_sqi_max() to take a phy_device argument directly, enabling support for setups with multiple PHYs. The previous assumption of a single PHY attached to a net_device no longer holds. Use ethnl_req_get_phydev() to identify the appropriate PHY device for the operation. Update linkstate_prepare_data() and related logic to accommodate this change, ensuring compatibility with multi-PHY configurations. Signed-off-by: Oleksij Rempel Signed-off-by: Paolo Abeni Stable-dep-of: 637399bf7e77 ("net: ethtool: netlink: Allow NULL nlattrs when getting a phy_device") Signed-off-by: Sasha Levin

ethtool: rss: fix hiding unsupported fields in dumps

2025-02-17T09:05:00+00:00

[ Upstream commit 244f8aa46fa9e2f4ea5fe0e04988b395d5e30fc7 ] Commit ec6e57beaf8b ("ethtool: rss: don't report key if device doesn't support it") intended to stop reporting key fields for additional rss contexts if device has a global hashing key. Later we added dump support and the filtering wasn't properly added there. So we end up reporting the key fields in dumps but not in dos: # ./pyynl/cli.py --spec netlink/specs/ethtool.yaml --do rss-get \ --json '{"header": {"dev-index":2}, "context": 1 }' { "header": { ... }, "context": 1, "indir": [0, 1, 2, 3, ...]] } # ./pyynl/cli.py --spec netlink/specs/ethtool.yaml --dump rss-get [ ... snip context 0 ... { "header": { ... }, "context": 1, "indir": [0, 1, 2, 3, ...], -> "input_xfrm": 255, -> "hfunc": 1, -> "hkey": "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000" } ] Hide these fields correctly. The drivers/net/hw/rss_ctx.py selftest catches this when run on a device with single key, already: # Check| At /root/./ksft-net-drv/drivers/net/hw/rss_ctx.py, line 381, in test_rss_context_dump: # Check| ksft_ne(set(data.get('hkey', [1])), {0}, "key is all zero") # Check failed {0} == {0} key is all zero not ok 8 rss_ctx.test_rss_context_dump Fixes: f6122900f4e2 ("ethtool: rss: support dumping RSS contexts") Reviewed-by: Gal Pressman Reviewed-by: Joe Damato Link: https://patch.msgid.link/20250201013040.725123-2-kuba@kernel.org Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

ethtool: ntuple: fix rss + ring_cookie check

2025-02-08T08:58:19+00:00

commit 2b91cc1214b165c25ac9b0885db89a0d3224028a upstream. The info.flow_type is for RXFH commands, ntuple flow_type is inside the flow spec. The check currently does nothing, as info.flow_type is 0 (or even uninitialized by user space) for ETHTOOL_SRXCLSRLINS. Fixes: 9e43ad7a1ede ("net: ethtool: only allow set_rxnfc with rss + ring_cookie if driver opts in") Reviewed-by: Gal Pressman Reviewed-by: Joe Damato Link: https://patch.msgid.link/20250201013040.725123-3-kuba@kernel.org Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman

ethtool: Fix access to uninitialized fields in set RXNFC command

2025-02-08T08:58:18+00:00

commit 94071909477677fc2a1abf3fb281f203f66cf3ca upstream. The check for non-zero ring with RSS is only relevant for ETHTOOL_SRXCLSRLINS command, in other cases the check tries to access memory which was not initialized by the userspace tool. Only perform the check in case of ETHTOOL_SRXCLSRLINS. Without this patch, filter deletion (for example) could statistically result in a false error: # ethtool --config-ntuple eth3 delete 484 rmgr: Cannot delete RX class rule: Invalid argument Cannot delete classification rule Fixes: 9e43ad7a1ede ("net: ethtool: only allow set_rxnfc with rss + ring_cookie if driver opts in") Link: https://lore.kernel.org/netdev/871a9ecf-1e14-40dd-bbd7-e90c92f89d47@nvidia.com/ Reviewed-by: Dragos Tatulea Reviewed-by: Tariq Toukan Signed-off-by: Gal Pressman Reviewed-by: Edward Cree Link: https://patch.msgid.link/20241202164805.1637093-1-gal@nvidia.com Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman

ethtool: Fix set RXNFC command with symmetric RSS hash

2025-02-08T08:58:06+00:00

[ Upstream commit 4f5a52adeb1ad675ca33f1e1eacd9c0bbaf393d4 ] The sanity check that both source and destination are set when symmetric RSS hash is requested is only relevant for ETHTOOL_SRXFH (rx-flow-hash), it should not be performed on any other commands (e.g. ETHTOOL_SRXCLSRLINS/ETHTOOL_SRXCLSRLDEL). This resolves accessing uninitialized 'info.data' field, and fixes false errors in rule insertion: # ethtool --config-ntuple eth2 flow-type ip4 dst-ip 255.255.255.255 action -1 loc 0 rmgr: Cannot insert RX class rule: Invalid argument Cannot insert classification rule Fixes: 13e59344fb9d ("net: ethtool: add support for symmetric-xor RSS hash") Cc: Ahmed Zaki Reviewed-by: Tariq Toukan Signed-off-by: Gal Pressman Reviewed-by: Michal Swiatkowski Reviewed-by: Edward Cree Reviewed-by: Ahmed Zaki Link: https://patch.msgid.link/20250126191845.316589-1-gal@nvidia.com Signed-off-by: Paolo Abeni Signed-off-by: Sasha Levin