kernel/linux.git/net/ethtool/ioctl.c, branch v6.1.168

net: ethtool: fix the error condition in ethtool_get_phy_stats_ethtool()

2026-01-11T14:19:27+00:00

commit 0dcc53abf58d572d34c5313de85f607cd33fc691 upstream. Clang static checker (scan-build) warning: net/ethtool/ioctl.c:line 2233, column 2 Called function pointer is null (null dereference). Return '-EOPNOTSUPP' when 'ops->get_ethtool_phy_stats' is NULL to fix this typo error. Fixes: 201ed315f967 ("net/ethtool/ioctl: split ethtool_get_phy_stats into multiple helpers") Signed-off-by: Su Hui Reviewed-by: Przemek Kitszel Reviewed-by: Hariprasad Kelam Link: https://lore.kernel.org/r/20240605034742.921751-1-suhui@nfschina.com Signed-off-by: Paolo Abeni Signed-off-by: Greg Kroah-Hartman

ethtool: Avoid overflowing userspace buffer on stats query

2026-01-11T14:18:43+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

net/ethtool/ioctl: split ethtool_get_phy_stats into multiple helpers

2026-01-11T14:18:43+00:00

[ Upstream commit 201ed315f9676809cd5b20a39206e964106d4f27 ] So that it's easier to follow and make sense of the branching and various conditions. Stats retrieval has been split into two separate functions ethtool_get_phy_stats_phydev & ethtool_get_phy_stats_ethtool. The former attempts to retrieve the stats using phydev & phy_ops, while the latter uses ethtool_ops. Actual n_stats validation & array allocation has been moved into a new ethtool_vzalloc_stats_array helper. This also fixes a potential NULL dereference of ops->get_ethtool_phy_stats where it was getting called in an else branch unconditionally without making sure it was actually present. Found by Linux Verification Center (linuxtesting.org) with the SVACE static analysis tool. Signed-off-by: Daniil Tatianin Reviewed-by: Andrew Lunn Signed-off-by: David S. Miller Stable-dep-of: 7b07be1ff1cb ("ethtool: Avoid overflowing userspace buffer on stats query") Signed-off-by: Sasha Levin

net/ethtool/ioctl: remove if n_stats checks from ethtool_get_phy_stats

2026-01-11T14:18:43+00:00

[ Upstream commit fd4778581d61d8848b532f8cdc9b325138748437 ] Now that we always early return if we don't have any stats we can remove these checks as they're no longer necessary. Signed-off-by: Daniil Tatianin Reviewed-by: Andrew Lunn Signed-off-by: David S. Miller Stable-dep-of: 7b07be1ff1cb ("ethtool: Avoid overflowing userspace buffer on stats query") Signed-off-by: Sasha Levin

ethtool: check device is present when getting link settings

2024-09-04T11:25:01+00:00

[ Upstream commit a699781c79ecf6cfe67fb00a0331b4088c7c8466 ] A sysfs reader can race with a device reset or removal, attempting to read device state when the device is not actually present. eg: [exception RIP: qed_get_current_link+17] #8 [ffffb9e4f2907c48] qede_get_link_ksettings at ffffffffc07a994a [qede] #9 [ffffb9e4f2907cd8] __rh_call_get_link_ksettings at ffffffff992b01a3 #10 [ffffb9e4f2907d38] __ethtool_get_link_ksettings at ffffffff992b04e4 #11 [ffffb9e4f2907d90] duplex_show at ffffffff99260300 #12 [ffffb9e4f2907e38] dev_attr_show at ffffffff9905a01c #13 [ffffb9e4f2907e50] sysfs_kf_seq_show at ffffffff98e0145b #14 [ffffb9e4f2907e68] seq_read at ffffffff98d902e3 #15 [ffffb9e4f2907ec8] vfs_read at ffffffff98d657d1 #16 [ffffb9e4f2907f00] ksys_read at ffffffff98d65c3f #17 [ffffb9e4f2907f38] do_syscall_64 at ffffffff98a052fb crash> struct net_device.state ffff9a9d21336000 state = 5, state 5 is __LINK_STATE_START (0b1) and __LINK_STATE_NOCARRIER (0b100). The device is not present, note lack of __LINK_STATE_PRESENT (0b10). This is the same sort of panic as observed in commit 4224cfd7fb65 ("net-sysfs: add check for netdevice being present to speed_show"). There are many other callers of __ethtool_get_link_ksettings() which don't have a device presence check. Move this check into ethtool to protect all callers. Fixes: d519e17e2d01 ("net: export device speed and duplex via sysfs") Fixes: 4224cfd7fb65 ("net-sysfs: add check for netdevice being present to speed_show") Signed-off-by: Jamie Bainbridge Link: https://patch.msgid.link/8bae218864beaa44ed01628140475b9bf641c5b0.1724393671.git.jamie.bainbridge@gmail.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

ipv6: Remove in6addr_any alternatives.

2023-09-19T10:28:10+00:00

[ Upstream commit 8cdc3223e78c43e1b60ea1c536a103e32fdca3c5 ] Some code defines the IPv6 wildcard address as a local variable and use it with memcmp() or ipv6_addr_equal(). Let's use in6addr_any and ipv6_addr_any() instead. Signed-off-by: Kuniyuki Iwashima Reviewed-by: Mark Bloch Reviewed-by: David Ahern Signed-off-by: David S. Miller Stable-dep-of: aa99e5f87bd5 ("tcp: Fix bind() regression for v4-mapped-v6 wildcard address.") Signed-off-by: Sasha Levin

ethtool: Fix uninitialized number of lanes

2023-05-17T09:53:37+00:00

[ Upstream commit 9ad685dbfe7e856bbf17a7177b64676d324d6ed7 ] It is not possible to set the number of lanes when setting link modes using the legacy IOCTL ethtool interface. Since 'struct ethtool_link_ksettings' is not initialized in this path, drivers receive an uninitialized number of lanes in 'struct ethtool_link_ksettings::lanes'. When this information is later queried from drivers, it results in the ethtool code making decisions based on uninitialized memory, leading to the following KMSAN splat [1]. In practice, this most likely only happens with the tun driver that simply returns whatever it got in the set operation. As far as I can tell, this uninitialized memory is not leaked to user space thanks to the 'ethtool_ops->cap_link_lanes_supported' check in linkmodes_prepare_data(). Fix by initializing the structure in the IOCTL path. Did not find any more call sites that pass an uninitialized structure when calling 'ethtool_ops::set_link_ksettings()'. [1] BUG: KMSAN: uninit-value in ethnl_update_linkmodes net/ethtool/linkmodes.c:273 [inline] BUG: KMSAN: uninit-value in ethnl_set_linkmodes+0x190b/0x19d0 net/ethtool/linkmodes.c:333 ethnl_update_linkmodes net/ethtool/linkmodes.c:273 [inline] ethnl_set_linkmodes+0x190b/0x19d0 net/ethtool/linkmodes.c:333 ethnl_default_set_doit+0x88d/0xde0 net/ethtool/netlink.c:640 genl_family_rcv_msg_doit net/netlink/genetlink.c:968 [inline] genl_family_rcv_msg net/netlink/genetlink.c:1048 [inline] genl_rcv_msg+0x141a/0x14c0 net/netlink/genetlink.c:1065 netlink_rcv_skb+0x3f8/0x750 net/netlink/af_netlink.c:2577 genl_rcv+0x40/0x60 net/netlink/genetlink.c:1076 netlink_unicast_kernel net/netlink/af_netlink.c:1339 [inline] netlink_unicast+0xf41/0x1270 net/netlink/af_netlink.c:1365 netlink_sendmsg+0x127d/0x1430 net/netlink/af_netlink.c:1942 sock_sendmsg_nosec net/socket.c:724 [inline] sock_sendmsg net/socket.c:747 [inline] ____sys_sendmsg+0xa24/0xe40 net/socket.c:2501 ___sys_sendmsg+0x2a1/0x3f0 net/socket.c:2555 __sys_sendmsg net/socket.c:2584 [inline] __do_sys_sendmsg net/socket.c:2593 [inline] __se_sys_sendmsg net/socket.c:2591 [inline] __x64_sys_sendmsg+0x36b/0x540 net/socket.c:2591 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Uninit was stored to memory at: tun_get_link_ksettings+0x37/0x60 drivers/net/tun.c:3544 __ethtool_get_link_ksettings+0x17b/0x260 net/ethtool/ioctl.c:441 ethnl_set_linkmodes+0xee/0x19d0 net/ethtool/linkmodes.c:327 ethnl_default_set_doit+0x88d/0xde0 net/ethtool/netlink.c:640 genl_family_rcv_msg_doit net/netlink/genetlink.c:968 [inline] genl_family_rcv_msg net/netlink/genetlink.c:1048 [inline] genl_rcv_msg+0x141a/0x14c0 net/netlink/genetlink.c:1065 netlink_rcv_skb+0x3f8/0x750 net/netlink/af_netlink.c:2577 genl_rcv+0x40/0x60 net/netlink/genetlink.c:1076 netlink_unicast_kernel net/netlink/af_netlink.c:1339 [inline] netlink_unicast+0xf41/0x1270 net/netlink/af_netlink.c:1365 netlink_sendmsg+0x127d/0x1430 net/netlink/af_netlink.c:1942 sock_sendmsg_nosec net/socket.c:724 [inline] sock_sendmsg net/socket.c:747 [inline] ____sys_sendmsg+0xa24/0xe40 net/socket.c:2501 ___sys_sendmsg+0x2a1/0x3f0 net/socket.c:2555 __sys_sendmsg net/socket.c:2584 [inline] __do_sys_sendmsg net/socket.c:2593 [inline] __se_sys_sendmsg net/socket.c:2591 [inline] __x64_sys_sendmsg+0x36b/0x540 net/socket.c:2591 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Uninit was stored to memory at: tun_set_link_ksettings+0x37/0x60 drivers/net/tun.c:3553 ethtool_set_link_ksettings+0x600/0x690 net/ethtool/ioctl.c:609 __dev_ethtool net/ethtool/ioctl.c:3024 [inline] dev_ethtool+0x1db9/0x2a70 net/ethtool/ioctl.c:3078 dev_ioctl+0xb07/0x1270 net/core/dev_ioctl.c:524 sock_do_ioctl+0x295/0x540 net/socket.c:1213 sock_ioctl+0x729/0xd90 net/socket.c:1316 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl+0x222/0x400 fs/ioctl.c:856 __x64_sys_ioctl+0x96/0xe0 fs/ioctl.c:856 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Local variable link_ksettings created at: ethtool_set_link_ksettings+0x54/0x690 net/ethtool/ioctl.c:577 __dev_ethtool net/ethtool/ioctl.c:3024 [inline] dev_ethtool+0x1db9/0x2a70 net/ethtool/ioctl.c:3078 Fixes: 012ce4dd3102 ("ethtool: Extend link modes settings uAPI with lanes") Reported-and-tested-by: syzbot+ef6edd9f1baaa54d6235@syzkaller.appspotmail.com Link: https://lore.kernel.org/netdev/0000000000004bb41105fa70f361@google.com/ Reviewed-by: Danielle Ratson Signed-off-by: Ido Schimmel Reviewed-by: Leon Romanovsky Signed-off-by: David S. Miller Signed-off-by: Sasha Levin

net/ethtool/ioctl: return -EOPNOTSUPP if we have no phy stats

2023-01-24T06:24:31+00:00

[ Upstream commit 9deb1e9fb88b1120a908676fa33bdf9e2eeaefce ] It's not very useful to copy back an empty ethtool_stats struct and return 0 if we didn't actually have any stats. This also allows for further simplification of this function in the future commits. Signed-off-by: Daniil Tatianin Reviewed-by: Andrew Lunn Signed-off-by: David S. Miller Signed-off-by: Sasha Levin

ethtool: avoiding integer overflow in ethtool_phys_id()

2022-12-31T12:33:03+00:00

[ Upstream commit 64a8f8f7127da228d59a39e2c5e75f86590f90b4 ] The value of an arithmetic expression "n * id.data" is subject to possible overflow due to a failure to cast operands to a larger data type before performing arithmetic. Used macro for multiplication instead operator for avoiding overflow. Found by Linux Verification Center (linuxtesting.org) with SVACE. Signed-off-by: Maxim Korotkov Reviewed-by: Alexander Lobakin Reviewed-by: Andrew Lunn Link: https://lore.kernel.org/r/20221122122901.22294-1-korotkov.maxim.s@gmail.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

net: phy: Add support for rate matching

2022-09-23T10:55:35+00:00

This adds support for rate matching (also known as rate adaptation) to the phy subsystem. The general idea is that the phy interface runs at one speed, and the MAC throttles the rate at which it sends packets to the link speed. There's a good overview of several techniques for achieving this at [1]. This patch adds support for three: pause-frame based (such as in Aquantia phys), CRS-based (such as in 10PASS-TS and 2BASE-TL), and open-loop-based (such as in 10GBASE-W). This patch makes a few assumptions and a few non assumptions about the types of rate matching available. First, it assumes that different phys may use different forms of rate matching. Second, it assumes that phys can use rate matching for any of their supported link speeds (e.g. if a phy supports 10BASE-T and XGMII, then it can adapt XGMII to 10BASE-T). Third, it does not assume that all interface modes will use the same form of rate matching. Fourth, it does not assume that all phy devices will support rate matching (even if some do). Relaxing or strengthening these (non-)assumptions could result in a different API. For example, if all interface modes were assumed to use the same form of rate matching, then a bitmask of interface modes supportting rate matching would suffice. For some better visibility into the process, the current rate matching mode is exposed as part of the ethtool ksettings. For the moment, only read access is supported. I'm not sure what userspace might want to configure yet (disable it altogether, disable just one mode, specify the mode to use, etc.). For the moment, since only pause-based rate adaptation support is added in the next few commits, rate matching can be disabled altogether by adjusting the advertisement. 802.3 calls this feature "rate adaptation" in clause 49 (10GBASE-R) and "rate matching" in clause 61 (10PASS-TL and 2BASE-TS). Aquantia also calls this feature "rate adaptation". I chose "rate matching" because it is shorter, and because Russell doesn't think "adaptation" is correct in this context. Signed-off-by: Sean Anderson Signed-off-by: David S. Miller