__netdev_update_features() expects the netdevice to be ops-locked, but
it gets called recursively on the lower level netdevices to sync their
features, and nothing locks those.
This commit fixes that, with the assumption that it shouldn't be possible
for both higher-level and lover-level netdevices to require the instance
lock, because that would lead to lock dependency warnings.
Without this, playing with higher level (e.g. vxlan) netdevices on top
of netdevices with instance locking enabled can run into issues:
WARNING: CPU: 59 PID: 206496 at ./include/net/netdev_lock.h:17 netif_napi_add_weight_locked+0x753/0xa60
[...]
Call Trace:
<TASK>
mlx5e_open_channel+0xc09/0x3740 [mlx5_core]
mlx5e_open_channels+0x1f0/0x770 [mlx5_core]
mlx5e_safe_switch_params+0x1b5/0x2e0 [mlx5_core]
set_feature_lro+0x1c2/0x330 [mlx5_core]
mlx5e_handle_feature+0xc8/0x140 [mlx5_core]
mlx5e_set_features+0x233/0x2e0 [mlx5_core]
__netdev_update_features+0x5be/0x1670
__netdev_update_features+0x71f/0x1670
dev_ethtool+0x21c5/0x4aa0
dev_ioctl+0x438/0xae0
sock_ioctl+0x2ba/0x690
__x64_sys_ioctl+0xa78/0x1700
do_syscall_64+0x6d/0x140
entry_SYSCALL_64_after_hwframe+0x4b/0x53
</TASK>
Fixes: 7e4d784f5810 ("net: hold netdev instance lock during rtnetlink operations")
Signed-off-by: Cosmin Ratiu <cratiu@nvidia.com>
Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Link: https://patch.msgid.link/20250509072850.2002821-1-cratiu@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Accidentally spotted while trying to understand what else needs
to be renamed to netif_ prefix. Most of the calls to dev_set_promiscuity
are adjacent to dev_set_allmulti or dev_disable_lro so it should
be safe to add the lock. Note that new netif_set_promiscuity is
currently unused, the locked paths call __dev_set_promiscuity directly.
Fixes: ad7c7b2172c3 ("net: hold netdev instance lock during sysfs operations")
Signed-off-by: Stanislav Fomichev <sdf@fomichev.me>
Link: https://patch.msgid.link/20250506011919.2882313-1-sdf@fomichev.me
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
__qdisc_destroy() calls into various qdiscs .destroy() op, which in turn
can call .ndo_setup_tc(), which requires the netdev instance lock.
This commit extends the critical section in
unregister_netdevice_many_notify() to cover dev_shutdown() (and
dev_tcx_uninstall() as a side-effect) and acquires the netdev instance
lock in __dev_change_net_namespace() for the other dev_shutdown() call.
This should now guarantee that for all qdisc ops, the netdev instance
lock is held during .ndo_setup_tc().
Fixes: a0527ee2df3f ("net: hold netdev instance lock during qdisc ndo_setup_tc")
Signed-off-by: Cosmin Ratiu <cratiu@nvidia.com>
Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Link: https://patch.msgid.link/20250505194713.1723399-1-cratiu@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
We need to be careful when operating on dev while in rtnl_create_link().
Some devices (vxlan) initialize netdev_ops in ->newlink, so later on.
Avoid using netdev_lock_ops(), the device isn't registered so we
cannot legally call its ops or generate any notifications for it.
netdev_ops_assert_locked_or_invisible() is safe to use, it checks
registration status first.
Reported-by: syzbot+de1c7d68a10e3f123bdd@syzkaller.appspotmail.com
Fixes: 04efcee6ef8d ("net: hold instance lock during NETDEV_CHANGE")
Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://patch.msgid.link/20250415151552.768373-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Lockdep found the following dependency:
&dev_instance_lock_key#3 -->
&rdev->wiphy.mtx -->
&net->xdp.lock -->
&xs->mutex -->
&dev_instance_lock_key#3
The first dependency is the problem. wiphy mutex should be outside
the instance locks. The problem happens in notifiers (as always)
for CLOSE. We only hold the instance lock for ops locked devices
during CLOSE, and WiFi netdevs are not ops locked. Unfortunately,
when we dev_close_many() during netns dismantle we may be holding
the instance lock of _another_ netdev when issuing a CLOSE for
a WiFi device.
Lockdep's "Possible unsafe locking scenario" only prints 3 locks
and we have 4, plus I think we'd need 3 CPUs, like this:
CPU0 CPU1 CPU2
---- ---- ----
lock(&xs->mutex);
lock(&dev_instance_lock_key#3);
lock(&rdev->wiphy.mtx);
lock(&net->xdp.lock);
lock(&xs->mutex);
lock(&rdev->wiphy.mtx);
lock(&dev_instance_lock_key#3);
Tho, I don't think that's possible as CPU1 and CPU2 would
be under rtnl_lock. Even if we have per-netns rtnl_lock and
wiphy can span network namespaces - CPU0 and CPU1 must be
in the same netns to see dev_instance_lock, so CPU0 can't
be installing a socket as CPU1 is tearing the netns down.
Regardless, our expected lock ordering is that wiphy lock
is taken before instance locks, so let's fix this.
Go over the ops locked and non-locked devices separately.
Note that calling dev_close_many() on an empty list is perfectly
fine. All processing (including RCU syncs) are conditional
on the list not being empty, already.
Fixes: 7e4d784f5810 ("net: hold netdev instance lock during rtnetlink operations")
Reported-by: syzbot+6f588c78bf765b62b450@syzkaller.appspotmail.com
Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Link: https://patch.msgid.link/20250412233011.309762-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Cosmin reports an issue with ipv6_add_dev being called from
NETDEV_CHANGE notifier:
[ 3455.008776] ? ipv6_add_dev+0x370/0x620
[ 3455.010097] ipv6_find_idev+0x96/0xe0
[ 3455.010725] addrconf_add_dev+0x1e/0xa0
[ 3455.011382] addrconf_init_auto_addrs+0xb0/0x720
[ 3455.013537] addrconf_notify+0x35f/0x8d0
[ 3455.014214] notifier_call_chain+0x38/0xf0
[ 3455.014903] netdev_state_change+0x65/0x90
[ 3455.015586] linkwatch_do_dev+0x5a/0x70
[ 3455.016238] rtnl_getlink+0x241/0x3e0
[ 3455.019046] rtnetlink_rcv_msg+0x177/0x5e0
Similarly, linkwatch might get to ipv6_add_dev without ops lock:
[ 3456.656261] ? ipv6_add_dev+0x370/0x620
[ 3456.660039] ipv6_find_idev+0x96/0xe0
[ 3456.660445] addrconf_add_dev+0x1e/0xa0
[ 3456.660861] addrconf_init_auto_addrs+0xb0/0x720
[ 3456.661803] addrconf_notify+0x35f/0x8d0
[ 3456.662236] notifier_call_chain+0x38/0xf0
[ 3456.662676] netdev_state_change+0x65/0x90
[ 3456.663112] linkwatch_do_dev+0x5a/0x70
[ 3456.663529] __linkwatch_run_queue+0xeb/0x200
[ 3456.663990] linkwatch_event+0x21/0x30
[ 3456.664399] process_one_work+0x211/0x610
[ 3456.664828] worker_thread+0x1cc/0x380
[ 3456.665691] kthread+0xf4/0x210
Reclassify NETDEV_CHANGE as a notifier that consistently runs under the
instance lock.
Link: https://lore.kernel.org/netdev/aac073de8beec3e531c86c101b274d434741c28e.camel@nvidia.com/
Reported-by: Cosmin Ratiu <cratiu@nvidia.com>
Tested-by: Cosmin Ratiu <cratiu@nvidia.com>
Fixes: ad7c7b2172c3 ("net: hold netdev instance lock during sysfs operations")
Signed-off-by: Stanislav Fomichev <sdf@fomichev.me>
Link: https://patch.msgid.link/20250404161122.3907628-1-sdf@fomichev.me
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
ipv6_add_dev might call dev_disable_lro which unconditionally grabs
instance lock, so it will deadlock during NETDEV_REGISTER. Switch
to netif_disable_lro.
Make sure all callers hold the instance lock as well.
Cc: Cosmin Ratiu <cratiu@nvidia.com>
Fixes: ad7c7b2172c3 ("net: hold netdev instance lock during sysfs operations")
Signed-off-by: Stanislav Fomichev <sdf@fomichev.me>
Link: https://patch.msgid.link/20250401163452.622454-4-sdf@fomichev.me
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Callers of inetdev_init can come from several places with inconsistent
expectation about netdev instance lock. Grab instance lock during
REGISTER (plus UP). Also solve the inconsistency with UNREGISTER
where it was locked only during move netns path.
WARNING: CPU: 10 PID: 1479 at ./include/net/netdev_lock.h:54
__netdev_update_features+0x65f/0xca0
__warn+0x81/0x180
__netdev_update_features+0x65f/0xca0
report_bug+0x156/0x180
handle_bug+0x4f/0x90
exc_invalid_op+0x13/0x60
asm_exc_invalid_op+0x16/0x20
__netdev_update_features+0x65f/0xca0
netif_disable_lro+0x30/0x1d0
inetdev_init+0x12f/0x1f0
inetdev_event+0x48b/0x870
notifier_call_chain+0x38/0xf0
register_netdevice+0x741/0x8b0
register_netdev+0x1f/0x40
mlx5e_probe+0x4e3/0x8e0 [mlx5_core]
auxiliary_bus_probe+0x3f/0x90
really_probe+0xc3/0x3a0
__driver_probe_device+0x80/0x150
driver_probe_device+0x1f/0x90
__device_attach_driver+0x7d/0x100
bus_for_each_drv+0x80/0xd0
__device_attach+0xb4/0x1c0
bus_probe_device+0x91/0xa0
device_add+0x657/0x870
Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Reported-by: Cosmin Ratiu <cratiu@nvidia.com>
Fixes: ad7c7b2172c3 ("net: hold netdev instance lock during sysfs operations")
Signed-off-by: Stanislav Fomichev <sdf@fomichev.me>
Link: https://patch.msgid.link/20250401163452.622454-3-sdf@fomichev.me
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Syzkaller points out that create_link path doesn't grab ops lock,
add it.
Reported-by: syzbot+08936936fe8132f91f1a@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/bpf/67e6b3e8.050a0220.2f068f.0079.GAE@google.com/
Fixes: 97246d6d21c2 ("net: hold netdev instance lock during ndo_bpf")
Signed-off-by: Stanislav Fomichev <sdf@fomichev.me>
Link: https://patch.msgid.link/20250331142814.1887506-1-sdf@fomichev.me
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Pull networking updates from Jakub Kicinski:
"Core & protocols:
- Continue Netlink conversions to per-namespace RTNL lock
(IPv4 routing, routing rules, routing next hops, ARP ioctls)
- Continue extending the use of netdev instance locks. As a driver
opt-in protect queue operations and (in due course) ethtool
operations with the instance lock and not RTNL lock.
- Support collecting TCP timestamps (data submitted, sent, acked) in
BPF, allowing for transparent (to the application) and lower
overhead tracking of TCP RPC performance.
- Tweak existing networking Rx zero-copy infra to support zero-copy
Rx via io_uring.
- Optimize MPTCP performance in single subflow mode by 29%.
- Enable GRO on packets which went thru XDP CPU redirect (were queued
for processing on a different CPU). Improving TCP stream
performance up to 2x.
- Improve performance of contended connect() by 200% by searching for
an available 4-tuple under RCU rather than a spin lock. Bring an
additional 229% improvement by tweaking hash distribution.
- Avoid unconditionally touching sk_tsflags on RX, improving
performance under UDP flood by as much as 10%.
- Avoid skb_clone() dance in ping_rcv() to improve performance under
ping flood.
- Avoid FIB lookup in netfilter if socket is available, 20% perf win.
- Rework network device creation (in-kernel) API to more clearly
identify network namespaces and their roles. There are up to 4
namespace roles but we used to have just 2 netns pointer arguments,
interpreted differently based on context.
- Use sysfs_break_active_protection() instead of trylock to avoid
deadlocks between unregistering objects and sysfs access.
- Add a new sysctl and sockopt for capping max retransmit timeout in
TCP.
- Support masking port and DSCP in routing rule matches.
- Support dumping IPv4 multicast addresses with RTM_GETMULTICAST.
- Support specifying at what time packet should be sent on AF_XDP
sockets.
- Expose TCP ULP diagnostic info (for TLS and MPTCP) to non-admin
users.
- Add Netlink YAML spec for WiFi (nl80211) and conntrack.
- Introduce EXPORT_IPV6_MOD() and EXPORT_IPV6_MOD_GPL() for symbols
which only need to be exported when IPv6 support is built as a
module.
- Age FDB entries based on Rx not Tx traffic in VxLAN, similar to
normal bridging.
- Allow users to specify source port range for GENEVE tunnels.
- netconsole: allow attaching kernel release, CPU ID and task name to
messages as metadata
Driver API:
- Continue rework / fixing of Energy Efficient Ethernet (EEE) across
the SW layers. Delegate the responsibilities to phylink where
possible. Improve its handling in phylib.
- Support symmetric OR-XOR RSS hashing algorithm.
- Support tracking and preserving IRQ affinity by NAPI itself.
- Support loopback mode speed selection for interface selftests.
Device drivers:
- Remove the IBM LCS driver for s390
- Remove the sb1000 cable modem driver
- Add support for SFP module access over SMBus
- Add MCTP transport driver for MCTP-over-USB
- Enable XDP metadata support in multiple drivers
- Ethernet high-speed NICs:
- Broadcom (bnxt):
- add PCIe TLP Processing Hints (TPH) support for new AMD
platforms
- support dumping RoCE queue state for debug
- opt into instance locking
- Intel (100G, ice, idpf):
- ice: rework MSI-X IRQ management and distribution
- ice: support for E830 devices
- iavf: add support for Rx timestamping
- iavf: opt into instance locking
- nVidia/Mellanox:
- mlx4: use page pool memory allocator for Rx
- mlx5: support for one PTP device per hardware clock
- mlx5: support for 200Gbps per-lane link modes
- mlx5: move IPSec policy check after decryption
- AMD/Solarflare:
- support FW flashing via devlink
- Cisco (enic):
- use page pool memory allocator for Rx
- enable 32, 64 byte CQEs
- get max rx/tx ring size from the device
- Meta (fbnic):
- support flow steering and RSS configuration
- report queue stats
- support TCP segmentation
- support IRQ coalescing
- support ring size configuration
- Marvell/Cavium:
- support AF_XDP
- Wangxun:
- support for PTP clock and timestamping
- Huawei (hibmcge):
- checksum offload
- add more statistics
- Ethernet virtual:
- VirtIO net:
- aggressively suppress Tx completions, improve perf by 96%
with 1 CPU and 55% with 2 CPUs
- expose NAPI to IRQ mapping and persist NAPI settings
- Google (gve):
- support XDP in DQO RDA Queue Format
- opt into instance locking
- Microsoft vNIC:
- support BIG TCP
- Ethernet NICs consumer, and embedded:
- Synopsys (stmmac):
- cleanup Tx and Tx clock setting and other link-focused
cleanups
- enable SGMII and 2500BASEX mode switching for Intel platforms
- support Sophgo SG2044
- Broadcom switches (b53):
- support for BCM53101
- TI:
- iep: add perout configuration support
- icssg: support XDP
- Cadence (macb):
- implement BQL
- Xilinx (axinet):
- support dynamic IRQ moderation and changing coalescing at
runtime
- implement BQL
- report standard stats
- MediaTek:
- support phylink managed EEE
- Intel:
- igc: don't restart the interface on every XDP program change
- RealTek (r8169):
- support reading registers of internal PHYs directly
- increase max jumbo packet size on RTL8125/RTL8126
- Airoha:
- support for RISC-V NPU packet processing unit
- enable scatter-gather and support MTU up to 9kB
- Tehuti (tn40xx):
- support cards with TN4010 MAC and an Aquantia AQR105 PHY
- Ethernet PHYs:
- support for TJA1102S, TJA1121
- dp83tg720: add randomized polling intervals for link detection
- dp83822: support changing the transmit amplitude voltage
- support for LEDs on 88q2xxx
- CAN:
- canxl: support Remote Request Substitution bit access
- flexcan: add S32G2/S32G3 SoC
- WiFi:
- remove cooked monitor support
- strict mode for better AP testing
- basic EPCS support
- OMI RX bandwidth reduction support
- batman-adv: add support for jumbo frames
- WiFi drivers:
- RealTek (rtw88):
- support RTL8814AE and RTL8814AU
- RealTek (rtw89):
- switch using wiphy_lock and wiphy_work
- add BB context to manipulate two PHY as preparation of MLO
- improve BT-coexistence mechanism to play A2DP smoothly
- Intel (iwlwifi):
- add new iwlmld sub-driver for latest HW/FW combinations
- MediaTek (mt76):
- preparation for mt7996 Multi-Link Operation (MLO) support
- Qualcomm/Atheros (ath12k):
- continued work on MLO
- Silabs (wfx):
- Wake-on-WLAN support
- Bluetooth:
- add support for skb TX SND/COMPLETION timestamping
- hci_core: enable buffer flow control for SCO/eSCO
- coredump: log devcd dumps into the monitor
- Bluetooth drivers:
- intel: add support to configure TX power
- nxp: handle bootloader error during cmd5 and cmd7"
* tag 'net-next-6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1681 commits)
unix: fix up for "apparmor: add fine grained af_unix mediation"
mctp: Fix incorrect tx flow invalidation condition in mctp-i2c
net: usb: asix: ax88772: Increase phy_name size
net: phy: Introduce PHY_ID_SIZE — minimum size for PHY ID string
net: libwx: fix Tx L4 checksum
net: libwx: fix Tx descriptor content for some tunnel packets
atm: Fix NULL pointer dereference
net: tn40xx: add pci-id of the aqr105-based Tehuti TN4010 cards
net: tn40xx: prepare tn40xx driver to find phy of the TN9510 card
net: tn40xx: create swnode for mdio and aqr105 phy and add to mdiobus
net: phy: aquantia: add essential functions to aqr105 driver
net: phy: aquantia: search for firmware-name in fwnode
net: phy: aquantia: add probe function to aqr105 for firmware loading
net: phy: Add swnode support to mdiobus_scan
gve: add XDP DROP and PASS support for DQ
gve: update XDP allocation path support RX buffer posting
gve: merge packet buffer size fields
gve: update GQ RX to use buf_size
gve: introduce config-based allocation for XDP
gve: remove xdp_xsk_done and xdp_xsk_wakeup statistics
...