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| author |   Stanislav Fomichev <sdf@fomichev.me> | 2025-04-10 09:11:17 -0700 |
|---|---|---|
| committer |   Jakub Kicinski <kuba@kernel.org> | 2025-04-11 18:53:20 -0700 |
| commit | f7a11cba0ed79d9d37941dddf69a8a655c8644bc (patch) | |
| tree | a81d2f547dcec68b7195c167f0fed6a8813e0524 | |
| parent | net: mctp: Set SOCK_RCU_FREE (diff) | |
| download | wireguard-linux-f7a11cba0ed79d9d37941dddf69a8a655c8644bc.tar.xz wireguard-linux-f7a11cba0ed79d9d37941dddf69a8a655c8644bc.zip | |
bonding: hold ops lock around get_link
syzbot reports a case of ethtool_ops->get_link being called without
ops lock:
ethtool_op_get_link+0x15/0x60 net/ethtool/ioctl.c:63
bond_check_dev_link+0x1fb/0x4b0 drivers/net/bonding/bond_main.c:864
bond_miimon_inspect drivers/net/bonding/bond_main.c:2734 [inline]
bond_mii_monitor+0x49d/0x3170 drivers/net/bonding/bond_main.c:2956
process_one_work kernel/workqueue.c:3238 [inline]
process_scheduled_works+0xac3/0x18e0 kernel/workqueue.c:3319
worker_thread+0x870/0xd50 kernel/workqueue.c:3400
kthread+0x7b7/0x940 kernel/kthread.c:464
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Commit 04efcee6ef8d ("net: hold instance lock during NETDEV_CHANGE")
changed to lockless __linkwatch_sync_dev in ethtool_op_get_link.
All paths except bonding are coming via locked ioctl. Add necessary
locking to bonding.
Reviewed-by: Hangbin Liu <liuhangbin@gmail.com>
Reported-by: syzbot+48c14f61594bdfadb086@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=48c14f61594bdfadb086
Fixes: 04efcee6ef8d ("net: hold instance lock during NETDEV_CHANGE")
Signed-off-by: Stanislav Fomichev <sdf@fomichev.me>
Link: https://patch.msgid.link/20250410161117.3519250-1-sdf@fomichev.me
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
| -rw-r--r-- | drivers/net/bonding/bond_main.c | 13 |
1 files changed, 9 insertions, 4 deletions
diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c index 950d8e4d86f8..8ea183da8d53 100644 --- a/drivers/net/bonding/bond_main.c +++ b/drivers/net/bonding/bond_main.c @@ -850,8 +850,9 @@ static int bond_check_dev_link(struct bonding *bond, struct net_device *slave_dev, int reporting) { const struct net_device_ops *slave_ops = slave_dev->netdev_ops; - struct ifreq ifr; struct mii_ioctl_data *mii; + struct ifreq ifr; + int ret; if (!reporting && !netif_running(slave_dev)) return 0; @@ -860,9 +861,13 @@ static int bond_check_dev_link(struct bonding *bond, return netif_carrier_ok(slave_dev) ? BMSR_LSTATUS : 0; /* Try to get link status using Ethtool first. */ - if (slave_dev->ethtool_ops->get_link) - return slave_dev->ethtool_ops->get_link(slave_dev) ? - BMSR_LSTATUS : 0; + if (slave_dev->ethtool_ops->get_link) { + netdev_lock_ops(slave_dev); + ret = slave_dev->ethtool_ops->get_link(slave_dev); + netdev_unlock_ops(slave_dev); + + return ret ? BMSR_LSTATUS : 0; + } /* Ethtool can't be used, fallback to MII ioctls. */ if (slave_ops->ndo_eth_ioctl) { |