diff options
| -rw-r--r-- | drivers/net/netkit.c | 69 | ||||
| -rw-r--r-- | include/linux/netdevice.h | 2 | ||||
| -rw-r--r-- | net/core/dev.c | 6 |
3 files changed, 75 insertions, 2 deletions
diff --git a/drivers/net/netkit.c b/drivers/net/netkit.c index b22bd0b6508a..1ec21aef348f 100644 --- a/drivers/net/netkit.c +++ b/drivers/net/netkit.c @@ -983,7 +983,15 @@ static void netkit_del_link(struct net_device *dev, struct list_head *head) if (peer) { nk = netkit_priv(peer); RCU_INIT_POINTER(nk->peer, NULL); - unregister_netdevice_queue(peer, head); + /* Guard against the peer already being in an unregister + * list (e.g. same-namespace teardown where the peer is + * in the caller's dev_kill_list). list_move_tail() on an + * already-queued device would otherwise corrupt that + * list's iteration. This situation can occur via netkit + * notifier, hence guard against this scenario. + */ + if (!unregister_netdevice_queued(peer)) + unregister_netdevice_queue(peer, head); } } @@ -1051,6 +1059,50 @@ static int netkit_change_link(struct net_device *dev, struct nlattr *tb[], return 0; } +static void netkit_check_lease_unregister(struct net_device *dev) +{ + LIST_HEAD(list_kill); + u32 q_idx; + + if (READ_ONCE(dev->reg_state) != NETREG_UNREGISTERING || + !dev->dev.parent) + return; + + netdev_lock_ops(dev); + for (q_idx = 0; q_idx < dev->real_num_rx_queues; q_idx++) { + struct net_device *tmp = dev; + struct netdev_rx_queue *rxq; + u32 tmp_q_idx = q_idx; + + rxq = __netif_get_rx_queue_lease(&tmp, &tmp_q_idx, + NETIF_PHYS_TO_VIRT); + if (rxq && tmp != dev && + tmp->netdev_ops == &netkit_netdev_ops) { + /* A single phys device can have multiple queues leased + * to one netkit device. We can only queue that netkit + * device once to the list_kill. Queues of that phys + * device can be leased with different individual netkit + * devices, hence we batch via list_kill. + */ + if (unregister_netdevice_queued(tmp)) + continue; + netkit_del_link(tmp, &list_kill); + } + } + netdev_unlock_ops(dev); + unregister_netdevice_many(&list_kill); +} + +static int netkit_notifier(struct notifier_block *this, + unsigned long event, void *ptr) +{ + struct net_device *dev = netdev_notifier_info_to_dev(ptr); + + if (event == NETDEV_UNREGISTER) + netkit_check_lease_unregister(dev); + return NOTIFY_DONE; +} + static size_t netkit_get_size(const struct net_device *dev) { return nla_total_size(sizeof(u32)) + /* IFLA_NETKIT_POLICY */ @@ -1127,18 +1179,31 @@ static struct rtnl_link_ops netkit_link_ops = { .maxtype = IFLA_NETKIT_MAX, }; +static struct notifier_block netkit_netdev_notifier = { + .notifier_call = netkit_notifier, +}; + static __init int netkit_mod_init(void) { + int ret; + BUILD_BUG_ON((int)NETKIT_NEXT != (int)TCX_NEXT || (int)NETKIT_PASS != (int)TCX_PASS || (int)NETKIT_DROP != (int)TCX_DROP || (int)NETKIT_REDIRECT != (int)TCX_REDIRECT); - return rtnl_link_register(&netkit_link_ops); + ret = rtnl_link_register(&netkit_link_ops); + if (ret) + return ret; + ret = register_netdevice_notifier(&netkit_netdev_notifier); + if (ret) + rtnl_link_unregister(&netkit_link_ops); + return ret; } static __exit void netkit_mod_exit(void) { + unregister_netdevice_notifier(&netkit_netdev_notifier); rtnl_link_unregister(&netkit_link_ops); } diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index e8aa9cc4075d..47417b2d48a4 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -3420,6 +3420,8 @@ static inline int dev_direct_xmit(struct sk_buff *skb, u16 queue_id) int register_netdevice(struct net_device *dev); void unregister_netdevice_queue(struct net_device *dev, struct list_head *head); void unregister_netdevice_many(struct list_head *head); +bool unregister_netdevice_queued(const struct net_device *dev); + static inline void unregister_netdevice(struct net_device *dev) { unregister_netdevice_queue(dev, NULL); diff --git a/net/core/dev.c b/net/core/dev.c index 2df8a2a5ecf5..e7bc95cbd1fa 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -12384,6 +12384,12 @@ static void netif_close_many_and_unlock_cond(struct list_head *close_head) #endif } +bool unregister_netdevice_queued(const struct net_device *dev) +{ + ASSERT_RTNL(); + return !list_empty(&dev->unreg_list); +} + void unregister_netdevice_many_notify(struct list_head *head, u32 portid, const struct nlmsghdr *nlh) { |