From cf124db566e6b036b8bcbe8decbed740bdfac8c6 Mon Sep 17 00:00:00 2001 From: "David S. Miller" Date: Mon, 8 May 2017 12:52:56 -0400 Subject: net: Fix inconsistent teardown and release of private netdev state. Network devices can allocate reasources and private memory using netdev_ops->ndo_init(). However, the release of these resources can occur in one of two different places. Either netdev_ops->ndo_uninit() or netdev->destructor(). The decision of which operation frees the resources depends upon whether it is necessary for all netdev refs to be released before it is safe to perform the freeing. netdev_ops->ndo_uninit() presumably can occur right after the NETDEV_UNREGISTER notifier completes and the unicast and multicast address lists are flushed. netdev->destructor(), on the other hand, does not run until the netdev references all go away. Further complicating the situation is that netdev->destructor() almost universally does also a free_netdev(). This creates a problem for the logic in register_netdevice(). Because all callers of register_netdevice() manage the freeing of the netdev, and invoke free_netdev(dev) if register_netdevice() fails. If netdev_ops->ndo_init() succeeds, but something else fails inside of register_netdevice(), it does call ndo_ops->ndo_uninit(). But it is not able to invoke netdev->destructor(). This is because netdev->destructor() will do a free_netdev() and then the caller of register_netdevice() will do the same. However, this means that the resources that would normally be released by netdev->destructor() will not be. Over the years drivers have added local hacks to deal with this, by invoking their destructor parts by hand when register_netdevice() fails. Many drivers do not try to deal with this, and instead we have leaks. Let's close this hole by formalizing the distinction between what private things need to be freed up by netdev->destructor() and whether the driver needs unregister_netdevice() to perform the free_netdev(). netdev->priv_destructor() performs all actions to free up the private resources that used to be freed by netdev->destructor(), except for free_netdev(). netdev->needs_free_netdev is a boolean that indicates whether free_netdev() should be done at the end of unregister_netdevice(). Now, register_netdevice() can sanely release all resources after ndo_ops->ndo_init() succeeds, by invoking both ndo_ops->ndo_uninit() and netdev->priv_destructor(). And at the end of unregister_netdevice(), we invoke netdev->priv_destructor() and optionally call free_netdev(). Signed-off-by: David S. Miller --- drivers/net/macvlan.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/net/macvlan.c') diff --git a/drivers/net/macvlan.c b/drivers/net/macvlan.c index 346ad2ff3998..67bf7ebae5c6 100644 --- a/drivers/net/macvlan.c +++ b/drivers/net/macvlan.c @@ -1092,7 +1092,7 @@ void macvlan_common_setup(struct net_device *dev) netif_keep_dst(dev); dev->priv_flags |= IFF_UNICAST_FLT; dev->netdev_ops = &macvlan_netdev_ops; - dev->destructor = free_netdev; + dev->needs_free_netdev = true; dev->header_ops = &macvlan_hard_header_ops; dev->ethtool_ops = &macvlan_ethtool_ops; } -- cgit v1.2.3 From e26f43faa0d79dd06e9e94829696b68b9940c2ee Mon Sep 17 00:00:00 2001 From: Vlad Yasevich Date: Wed, 21 Jun 2017 07:59:16 -0400 Subject: macvlan: Do not return error when setting the same mac address The user currently gets an EBUSY error when attempting to set the mac address on a macvlan device to the same value. This should really be a no-op as nothing changes. Catch the condition and return early. Signed-off-by: Vladislav Yasevich Signed-off-by: David S. Miller --- drivers/net/macvlan.c | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'drivers/net/macvlan.c') diff --git a/drivers/net/macvlan.c b/drivers/net/macvlan.c index 67bf7ebae5c6..de214fbda173 100644 --- a/drivers/net/macvlan.c +++ b/drivers/net/macvlan.c @@ -703,6 +703,10 @@ static int macvlan_set_mac_address(struct net_device *dev, void *p) if (!is_valid_ether_addr(addr->sa_data)) return -EADDRNOTAVAIL; + /* If the addresses are the same, this is a no-op */ + if (ether_addr_equal(dev->dev_addr, addr->sa_data)) + return 0; + if (vlan->mode == MACVLAN_MODE_PASSTHRU) { dev_set_mac_address(vlan->lowerdev, addr); return 0; -- cgit v1.2.3 From e696cda7bd091411705a4e868ce480eaa3082dbf Mon Sep 17 00:00:00 2001 From: Vlad Yasevich Date: Wed, 21 Jun 2017 07:59:17 -0400 Subject: macvlan: Fix passthru macvlan mac address inheritance When a lower device of the passthru macvlan changes it's address, passthru macvlan is supposed to change it's own address as well. However, that doesn't happen correctly because the check in macvlan_addr_busy() will catch the fact that the lower level (port) mac address is the same as the address we are trying to assign to the macvlan, and return an error. As a reasult, the address of the passthru macvlan device is never changed. The same thing happens when the user attempts to change the mac address of the passthru macvlan. The simple solution appers to be to not check against the lower device in case of passthru macvlan device, since the 2 addresses are _supposed_ to be the same. Signed-off-by: Vladislav Yasevich Signed-off-by: David S. Miller --- drivers/net/macvlan.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'drivers/net/macvlan.c') diff --git a/drivers/net/macvlan.c b/drivers/net/macvlan.c index de214fbda173..0c9c6da3427a 100644 --- a/drivers/net/macvlan.c +++ b/drivers/net/macvlan.c @@ -185,7 +185,8 @@ static bool macvlan_addr_busy(const struct macvlan_port *port, * currently in use by the underlying device or * another macvlan. */ - if (ether_addr_equal_64bits(port->dev->dev_addr, addr)) + if (!port->passthru && + ether_addr_equal_64bits(port->dev->dev_addr, addr)) return true; if (macvlan_hash_lookup(port, addr)) -- cgit v1.2.3 From 43c2d578a0ce0d6067a02b46461811aced551425 Mon Sep 17 00:00:00 2001 From: Vlad Yasevich Date: Wed, 21 Jun 2017 07:59:18 -0400 Subject: macvlan: convert port passthru to flags. Convert the port passthru boolean into flags with accesor functions. Signed-off-by: Vladislav Yasevich Signed-off-by: David S. Miller --- drivers/net/macvlan.c | 37 ++++++++++++++++++++++++------------- 1 file changed, 24 insertions(+), 13 deletions(-) (limited to 'drivers/net/macvlan.c') diff --git a/drivers/net/macvlan.c b/drivers/net/macvlan.c index 0c9c6da3427a..4d013ca79dae 100644 --- a/drivers/net/macvlan.c +++ b/drivers/net/macvlan.c @@ -39,13 +39,15 @@ #define MACVLAN_HASH_SIZE (1<flags & MACVLAN_F_PASSTHRU; +} + +static inline void macvlan_set_passthru(struct macvlan_port *port) +{ + port->flags |= MACVLAN_F_PASSTHRU; +} + /* Hash Ethernet address */ static u32 macvlan_eth_hash(const unsigned char *addr) { @@ -185,7 +197,7 @@ static bool macvlan_addr_busy(const struct macvlan_port *port, * currently in use by the underlying device or * another macvlan. */ - if (!port->passthru && + if (!macvlan_passthru(port) && ether_addr_equal_64bits(port->dev->dev_addr, addr)) return true; @@ -446,7 +458,7 @@ static rx_handler_result_t macvlan_handle_frame(struct sk_buff **pskb) } macvlan_forward_source(skb, port, eth->h_source); - if (port->passthru) + if (macvlan_passthru(port)) vlan = list_first_or_null_rcu(&port->vlans, struct macvlan_dev, list); else @@ -575,7 +587,7 @@ static int macvlan_open(struct net_device *dev) struct net_device *lowerdev = vlan->lowerdev; int err; - if (vlan->port->passthru) { + if (macvlan_passthru(vlan->port)) { if (!(vlan->flags & MACVLAN_FLAG_NOPROMISC)) { err = dev_set_promiscuity(lowerdev, 1); if (err < 0) @@ -650,7 +662,7 @@ static int macvlan_stop(struct net_device *dev) dev_uc_unsync(lowerdev, dev); dev_mc_unsync(lowerdev, dev); - if (vlan->port->passthru) { + if (macvlan_passthru(vlan->port)) { if (!(vlan->flags & MACVLAN_FLAG_NOPROMISC)) dev_set_promiscuity(lowerdev, -1); goto hash_del; @@ -683,7 +695,7 @@ static int macvlan_sync_address(struct net_device *dev, unsigned char *addr) if (macvlan_addr_busy(vlan->port, addr)) return -EBUSY; - if (!vlan->port->passthru) { + if (!macvlan_passthru(vlan->port)) { err = dev_uc_add(lowerdev, addr); if (err) return err; @@ -933,7 +945,7 @@ static int macvlan_fdb_add(struct ndmsg *ndm, struct nlattr *tb[], /* Support unicast filter only on passthru devices. * Multicast filter should be allowed on all devices. */ - if (!vlan->port->passthru && is_unicast_ether_addr(addr)) + if (!macvlan_passthru(vlan->port) && is_unicast_ether_addr(addr)) return -EOPNOTSUPP; if (flags & NLM_F_REPLACE) @@ -957,7 +969,7 @@ static int macvlan_fdb_del(struct ndmsg *ndm, struct nlattr *tb[], /* Support unicast filter only on passthru devices. * Multicast filter should be allowed on all devices. */ - if (!vlan->port->passthru && is_unicast_ether_addr(addr)) + if (!macvlan_passthru(vlan->port) && is_unicast_ether_addr(addr)) return -EOPNOTSUPP; if (is_unicast_ether_addr(addr)) @@ -1125,7 +1137,6 @@ static int macvlan_port_create(struct net_device *dev) if (port == NULL) return -ENOMEM; - port->passthru = false; port->dev = dev; INIT_LIST_HEAD(&port->vlans); for (i = 0; i < MACVLAN_HASH_SIZE; i++) @@ -1331,7 +1342,7 @@ int macvlan_common_newlink(struct net *src_net, struct net_device *dev, port = macvlan_port_get_rtnl(lowerdev); /* Only 1 macvlan device can be created in passthru mode */ - if (port->passthru) { + if (macvlan_passthru(port)) { /* The macvlan port must be not created this time, * still goto destroy_macvlan_port for readability. */ @@ -1357,7 +1368,7 @@ int macvlan_common_newlink(struct net *src_net, struct net_device *dev, err = -EINVAL; goto destroy_macvlan_port; } - port->passthru = true; + macvlan_set_passthru(port); eth_hw_addr_inherit(dev, lowerdev); } @@ -1439,7 +1450,7 @@ static int macvlan_changelink(struct net_device *dev, if (data && data[IFLA_MACVLAN_FLAGS]) { __u16 flags = nla_get_u16(data[IFLA_MACVLAN_FLAGS]); bool promisc = (flags ^ vlan->flags) & MACVLAN_FLAG_NOPROMISC; - if (vlan->port->passthru && promisc) { + if (macvlan_passthru(vlan->port) && promisc) { int err; if (flags & MACVLAN_FLAG_NOPROMISC) @@ -1602,7 +1613,7 @@ static int macvlan_device_event(struct notifier_block *unused, } break; case NETDEV_CHANGEADDR: - if (!port->passthru) + if (!macvlan_passthru(port)) return NOTIFY_DONE; vlan = list_first_entry_or_null(&port->vlans, -- cgit v1.2.3 From 18c8c54de9a619ba5533419e0170433e20c0ee3e Mon Sep 17 00:00:00 2001 From: Vlad Yasevich Date: Wed, 21 Jun 2017 07:59:19 -0400 Subject: macvlan: Let passthru macvlan correctly restore lower mac address Passthru macvlans directly change the mac address of the lower level device. That's OK, but after the macvlan is deleted, the lower device is left with changed address and one needs to reboot to bring back the origina HW addresses. This scenario is actually quite common with passthru macvtap devices. This patch attempts to solve this, by storing the mac address of the lower device in macvlan_port structure and keeping track of it through the changes. After this patch, any changes to the lower device mac address done trough the macvlan device, will be reverted back. Any changs done directly to the lower device mac address will be kept. Signed-off-by: Vladislav Yasevich Signed-off-by: David S. Miller --- drivers/net/macvlan.c | 47 ++++++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 44 insertions(+), 3 deletions(-) (limited to 'drivers/net/macvlan.c') diff --git a/drivers/net/macvlan.c b/drivers/net/macvlan.c index 4d013ca79dae..72b801803aa4 100644 --- a/drivers/net/macvlan.c +++ b/drivers/net/macvlan.c @@ -40,6 +40,7 @@ #define MACVLAN_BC_QUEUE_LEN 1000 #define MACVLAN_F_PASSTHRU 1 +#define MACVLAN_F_ADDRCHANGE 2 struct macvlan_port { struct net_device *dev; @@ -51,6 +52,7 @@ struct macvlan_port { int count; struct hlist_head vlan_source_hash[MACVLAN_HASH_SIZE]; DECLARE_BITMAP(mc_filter, MACVLAN_MC_FILTER_SZ); + unsigned char perm_addr[ETH_ALEN]; }; struct macvlan_source_entry { @@ -78,6 +80,21 @@ static inline void macvlan_set_passthru(struct macvlan_port *port) port->flags |= MACVLAN_F_PASSTHRU; } +static inline bool macvlan_addr_change(const struct macvlan_port *port) +{ + return port->flags & MACVLAN_F_ADDRCHANGE; +} + +static inline void macvlan_set_addr_change(struct macvlan_port *port) +{ + port->flags |= MACVLAN_F_ADDRCHANGE; +} + +static inline void macvlan_clear_addr_change(struct macvlan_port *port) +{ + port->flags &= ~MACVLAN_F_ADDRCHANGE; +} + /* Hash Ethernet address */ static u32 macvlan_eth_hash(const unsigned char *addr) { @@ -193,11 +210,11 @@ static void macvlan_hash_change_addr(struct macvlan_dev *vlan, static bool macvlan_addr_busy(const struct macvlan_port *port, const unsigned char *addr) { - /* Test to see if the specified multicast address is + /* Test to see if the specified address is * currently in use by the underlying device or * another macvlan. */ - if (!macvlan_passthru(port) && + if (!macvlan_passthru(port) && !macvlan_addr_change(port) && ether_addr_equal_64bits(port->dev->dev_addr, addr)) return true; @@ -685,6 +702,7 @@ static int macvlan_sync_address(struct net_device *dev, unsigned char *addr) { struct macvlan_dev *vlan = netdev_priv(dev); struct net_device *lowerdev = vlan->lowerdev; + struct macvlan_port *port = vlan->port; int err; if (!(dev->flags & IFF_UP)) { @@ -695,7 +713,7 @@ static int macvlan_sync_address(struct net_device *dev, unsigned char *addr) if (macvlan_addr_busy(vlan->port, addr)) return -EBUSY; - if (!macvlan_passthru(vlan->port)) { + if (!macvlan_passthru(port)) { err = dev_uc_add(lowerdev, addr); if (err) return err; @@ -705,6 +723,15 @@ static int macvlan_sync_address(struct net_device *dev, unsigned char *addr) macvlan_hash_change_addr(vlan, addr); } + if (macvlan_passthru(port) && !macvlan_addr_change(port)) { + /* Since addr_change isn't set, we are here due to lower + * device change. Save the lower-dev address so we can + * restore it later. + */ + ether_addr_copy(vlan->port->perm_addr, + lowerdev->dev_addr); + } + macvlan_clear_addr_change(port); return 0; } @@ -721,6 +748,7 @@ static int macvlan_set_mac_address(struct net_device *dev, void *p) return 0; if (vlan->mode == MACVLAN_MODE_PASSTHRU) { + macvlan_set_addr_change(vlan->port); dev_set_mac_address(vlan->lowerdev, addr); return 0; } @@ -1138,6 +1166,7 @@ static int macvlan_port_create(struct net_device *dev) return -ENOMEM; port->dev = dev; + ether_addr_copy(port->perm_addr, dev->dev_addr); INIT_LIST_HEAD(&port->vlans); for (i = 0; i < MACVLAN_HASH_SIZE; i++) INIT_HLIST_HEAD(&port->vlan_hash[i]); @@ -1177,6 +1206,18 @@ static void macvlan_port_destroy(struct net_device *dev) kfree_skb(skb); } + /* If the lower device address has been changed by passthru + * macvlan, put it back. + */ + if (macvlan_passthru(port) && + !ether_addr_equal(port->dev->dev_addr, port->perm_addr)) { + struct sockaddr sa; + + sa.sa_family = port->dev->type; + memcpy(&sa.sa_data, port->perm_addr, port->dev->addr_len); + dev_set_mac_address(port->dev, &sa); + } + kfree(port); } -- cgit v1.2.3