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2021-11-29net: Write lock dev_base_lock without disabling bottom halves.Sebastian Andrzej Siewior1-4/+4
The writer acquires dev_base_lock with disabled bottom halves. The reader can acquire dev_base_lock without disabling bottom halves because there is no writer in softirq context. On PREEMPT_RT the softirqs are preemptible and local_bh_disable() acts as a lock to ensure that resources, that are protected by disabling bottom halves, remain protected. This leads to a circular locking dependency if the lock acquired with disabled bottom halves (as in write_lock_bh()) and somewhere else with enabled bottom halves (as by read_lock() in netstat_show()) followed by disabling bottom halves (cxgb_get_stats() -> t4_wr_mbox_meat_timeout() -> spin_lock_bh()). This is the reverse locking order. All read_lock() invocation are from sysfs callback which are not invoked from softirq context. Therefore there is no need to disable bottom halves while acquiring a write lock. Acquire the write lock of dev_base_lock without disabling bottom halves. Reported-by: Pei Zhang <pezhang@redhat.com> Reported-by: Luis Claudio R. Goncalves <lgoncalv@redhat.com> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-11-23net: remove .ndo_change_proto_downJakub Kicinski1-2/+1
.ndo_change_proto_down was added seemingly to enable out-of-tree implementations. Over 2.5yrs later we still have no real users upstream. Hardwire the generic implementation for now, we can revert once real users materialize. (rocker is a test vehicle, not a user.) We need to drop the optimization on the sysfs side, because unlike ndos priv_flags will be changed at runtime, so we'd need READ_ONCE/WRITE_ONCE everywhere.. Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-11-22net: annotate accesses to dev->gso_max_segsEric Dumazet1-2/+2
dev->gso_max_segs is written under RTNL protection, or when the device is not yet visible, but is read locklessly. Add netif_set_gso_max_segs() helper. Add the READ_ONCE()/WRITE_ONCE() pairs, and use netif_set_gso_max_segs() where we can to better document what is going on. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-24net: rtnetlink: use __dev_addr_set()Jakub Kicinski1-2/+2
Get it ready for constant netdev->dev_addr. Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-21net/core: Remove unused assignment operations and variableluo penghao1-2/+1
Although if_info_size is assigned, it has not been used. And the variable should also be deleted. The clang_analyzer complains as follows: net/core/rtnetlink.c:3806: warning: Although the value stored to 'if_info_size' is used in the enclosing expression, the value is never actually read from 'if_info_size'. Reported-by: Zeal Robot <zealci@zte.com.cn> Signed-off-by: luo penghao <luo.penghao@zte.com.cn> Reviewed-by: Simon Horman <horms@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-16net: make use of helper netif_is_bridge_master()Kyungrok Chung1-1/+1
Make use of netdev helper functions to improve code readability. Replace 'dev->priv_flags & IFF_EBRIDGE' with netif_is_bridge_master(dev). Signed-off-by: Kyungrok Chung <acadx0@gmail.com> Reviewed-by: Nikolay Aleksandrov <nikolay@nvidia.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-08Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski1-1/+1
No conflicts. Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-10-06rtnetlink: fix if_nlmsg_stats_size() under estimationEric Dumazet1-1/+1
rtnl_fill_statsinfo() is filling skb with one mandatory if_stats_msg structure. nlmsg_put(skb, pid, seq, type, sizeof(struct if_stats_msg), flags); But if_nlmsg_stats_size() never considered the needed storage. This bug did not show up because alloc_skb(X) allocates skb with extra tailroom, because of added alignments. This could very well be changed in the future to have deterministic behavior. Fixes: 10c9ead9f3c6 ("rtnetlink: add new RTM_GETSTATS message to dump link stats") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Roopa Prabhu <roopa@nvidia.com> Acked-by: Roopa Prabhu <roopa@nvidia.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-19net: rtnetlink: convert rcu_assign_pointer to RCU_INIT_POINTERYajun Deng1-2/+2
It no need barrier when assigning a NULL value to an RCU protected pointer. So use RCU_INIT_POINTER() instead for more fast. Signed-off-by: Yajun Deng <yajun.deng@linux.dev> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-27Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski1-1/+2
drivers/net/wwan/mhi_wwan_mbim.c - drop the extra arg. Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-08-26rtnetlink: Return correct error on changing device netnsAndrey Ignatov1-1/+2
Currently when device is moved between network namespaces using RTM_NEWLINK message type and one of netns attributes (FLA_NET_NS_PID, IFLA_NET_NS_FD, IFLA_TARGET_NETNSID) but w/o specifying IFLA_IFNAME, and target namespace already has device with same name, userspace will get EINVAL what is confusing and makes debugging harder. Fix it so that userspace gets more appropriate EEXIST instead what makes debugging much easier. Before: # ./ifname.sh + ip netns add ns0 + ip netns exec ns0 ip link add l0 type dummy + ip netns exec ns0 ip link show l0 8: l0: <BROADCAST,NOARP> mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000 link/ether 66:90:b5:d5:78:69 brd ff:ff:ff:ff:ff:ff + ip link add l0 type dummy + ip link show l0 10: l0: <BROADCAST,NOARP> mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000 link/ether 6e:c6:1f:15:20:8d brd ff:ff:ff:ff:ff:ff + ip link set l0 netns ns0 RTNETLINK answers: Invalid argument After: # ./ifname.sh + ip netns add ns0 + ip netns exec ns0 ip link add l0 type dummy + ip netns exec ns0 ip link show l0 8: l0: <BROADCAST,NOARP> mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000 link/ether 1e:4a:72:e3:e3:8f brd ff:ff:ff:ff:ff:ff + ip link add l0 type dummy + ip link show l0 10: l0: <BROADCAST,NOARP> mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000 link/ether f2:fc:fe:2b:7d:a6 brd ff:ff:ff:ff:ff:ff + ip link set l0 netns ns0 RTNETLINK answers: File exists The problem is that do_setlink() passes its `char *ifname` argument, that it gets from a caller, to __dev_change_net_namespace() as is (as `const char *pat`), but semantics of ifname and pat can be different. For example, __rtnl_newlink() does this: net/core/rtnetlink.c 3270 char ifname[IFNAMSIZ]; ... 3286 if (tb[IFLA_IFNAME]) 3287 nla_strscpy(ifname, tb[IFLA_IFNAME], IFNAMSIZ); 3288 else 3289 ifname[0] = '\0'; ... 3364 if (dev) { ... 3394 return do_setlink(skb, dev, ifm, extack, tb, ifname, status); 3395 } , i.e. do_setlink() gets ifname pointer that is always valid no matter if user specified IFLA_IFNAME or not and then do_setlink() passes this ifname pointer as is to __dev_change_net_namespace() as pat argument. But the pat (pattern) in __dev_change_net_namespace() is used as: net/core/dev.c 11198 err = -EEXIST; 11199 if (__dev_get_by_name(net, dev->name)) { 11200 /* We get here if we can't use the current device name */ 11201 if (!pat) 11202 goto out; 11203 err = dev_get_valid_name(net, dev, pat); 11204 if (err < 0) 11205 goto out; 11206 } As the result the `goto out` path on line 11202 is neven taken and instead of returning EEXIST defined on line 11198, __dev_change_net_namespace() returns an error from dev_get_valid_name() and this, in turn, will be EINVAL for ifname[0] = '\0' set earlier. Fixes: d8a5ec672768 ("[NET]: netlink support for moving devices between network namespaces.") Signed-off-by: Andrey Ignatov <rdna@fb.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-11net: Support filtering interfaces on no masterLahav Schlesinger1-0/+7
Currently there's support for filtering neighbours/links for interfaces which have a specific master device (using the IFLA_MASTER/NDA_MASTER attributes). This patch adds support for filtering interfaces/neighbours dump for interfaces that *don't* have a master. Signed-off-by: Lahav Schlesinger <lschlesinger@drivenets.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://lore.kernel.org/r/20210810090658.2778960-1-lschlesinger@drivenets.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-08-04net: add extack arg for link opsRocco Yue1-4/+5
Pass extack arg to validate_linkmsg and validate_link_af callbacks. If a netlink attribute has a reject_message, use the extended ack mechanism to carry the message back to user space. Signed-off-by: Rocco Yue <rocco.yue@mediatek.com> Reviewed-by: David Ahern <dsahern@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-27net: netlink: add the case when nlh is NULLYajun Deng1-5/+1
Add the case when nlh is NULL in nlmsg_report(), so that the caller doesn't need to deal with this case. Signed-off-by: Yajun Deng <yajun.deng@linux.dev> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-16rtnetlink: use nlmsg_notify() in rtnetlink_send()Yajun Deng1-8/+1
The netlink_{broadcast, unicast} don't deal with 'if (err > 0' statement but nlmsg_{multicast, unicast} do. The nlmsg_notify() contains them. so use nlmsg_notify() instead. so that the caller wouldn't deal with 'if (err > 0' statement. v2: use nlmsg_notify() will do well. Signed-off-by: Yajun Deng <yajun.deng@linux.dev> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-29net: say "local" instead of "static" addresses in ndo_dflt_fdb_{add,del}Vladimir Oltean1-2/+2
"Static" is a loaded word, and probably not what the author meant when the code was written. In particular, this looks weird: $ bridge fdb add dev swp0 00:01:02:03:04:05 local # totally fine, but $ bridge fdb add dev swp0 00:01:02:03:04:05 static [ 2020.708298] swp0: FDB only supports static addresses # hmm what? By looking at the implementation which uses dev_uc_add/dev_uc_del it is absolutely clear that only local addresses are supported, and the proper Network Unreachability Detection state is being used for this purpose (user space indeed sets NUD_PERMANENT when local addresses are meant). So it is just the message that is wrong, fix it. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-29net: use netdev_info in ndo_dflt_fdb_{add,del}Vladimir Oltean1-3/+3
Use the more modern printk helper for network interfaces, which also contains information about the associated struct device, and results in overall shorter line lengths compared to printing an open-coded dev->name. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-19Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski1-3/+5
Trivial conflicts in net/can/isotp.c and tools/testing/selftests/net/mptcp/mptcp_connect.sh scaled_ppm_to_ppb() was moved from drivers/ptp/ptp_clock.c to include/linux/ptp_clock_kernel.h in -next so re-apply the fix there. Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-06-12wwan: add interface creation supportJohannes Berg1-0/+1
Add support to create (and destroy) interfaces via a new rtnetlink kind "wwan". The responsible driver has to use the new wwan_register_ops() to make this possible. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: Sergey Ryazanov <ryazanov.s.a@gmail.com> Signed-off-by: Loic Poulain <loic.poulain@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-12rtnetlink: add IFLA_PARENT_[DEV|DEV_BUS]_NAMEJohannes Berg1-0/+10
In some cases, for example in the upcoming WWAN framework changes, there's no natural "parent netdev", so sometimes dummy netdevs are created or similar. IFLA_PARENT_DEV_NAME is a new attribute intended to contain a device (sysfs, struct device) name that can be used instead when creating a new netdev, if the rtnetlink family implements it. As suggested by Parav Pandit, we also introduce IFLA_PARENT_DEV_BUS_NAME attribute in order to uniquely identify a device on the system (with bus/name pair). ip-link(8) support for the generic parent device attributes will help us avoid code duplication, so no other link type will require a custom code to handle the parent name attribute. E.g. the WWAN interface creation command will looks like this: $ ip link add wwan0-1 parent-dev wwan0 type wwan channel-id 1 So, some future subsystem (or driver) FOO will have an interface creation command that looks like this: $ ip link add foo1-3 parent-dev foo1 type foo bar-id 3 baz-type Y Below is an example of dumping link info of a random device with these new attributes: $ ip --details link show wlp0s20f3 4: wlp0s20f3: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP mode DORMANT group default qlen 1000 ... parent_bus pci parent_dev 0000:00:14.3 Co-developed-by: Sergey Ryazanov <ryazanov.s.a@gmail.com> Signed-off-by: Sergey Ryazanov <ryazanov.s.a@gmail.com> Co-developed-by: Loic Poulain <loic.poulain@linaro.org> Signed-off-by: Loic Poulain <loic.poulain@linaro.org> Suggested-by: Sergey Ryazanov <ryazanov.s.a@gmail.com> Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-12rtnetlink: add alloc() method to rtnl_link_opsJohannes Berg1-5/+14
In order to make rtnetlink ops that can create different kinds of devices, like what we want to add to the WWAN framework, the priv_size and setup parameters aren't quite sufficient. Make this easier to manage by allowing ops to allocate their own netdev via an @alloc method that gets the tb netlink data. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: Sergey Ryazanov <ryazanov.s.a@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-10rtnetlink: Fix regression in bridge VLAN configurationIdo Schimmel1-3/+5
Cited commit started returning errors when notification info is not filled by the bridge driver, resulting in the following regression: # ip link add name br1 type bridge vlan_filtering 1 # bridge vlan add dev br1 vid 555 self pvid untagged RTNETLINK answers: Invalid argument As long as the bridge driver does not fill notification info for the bridge device itself, an empty notification should not be considered as an error. This is explained in commit 59ccaaaa49b5 ("bridge: dont send notification when skb->len == 0 in rtnl_bridge_notify"). Fix by removing the error and add a comment to avoid future bugs. Fixes: a8db57c1d285 ("rtnetlink: Fix missing error code in rtnl_bridge_notify()") Signed-off-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: Nikolay Aleksandrov <nikolay@nvidia.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-07Merge ra.kernel.org:/pub/scm/linux/kernel/git/netdev/netDavid S. Miller1-1/+3
Bug fixes overlapping feature additions and refactoring, mostly. Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-03rtnetlink: Fix missing error code in rtnl_bridge_notify()Jiapeng Chong1-1/+3
The error code is missing in this code scenario, add the error code '-EINVAL' to the return value 'err'. Eliminate the follow smatch warning: net/core/rtnetlink.c:4834 rtnl_bridge_notify() warn: missing error code 'err'. Reported-by: Abaci Robot <abaci@linux.alibaba.com> Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-03rtnetlink: Fix spelling mistakesZheng Yongjun1-4/+4
Signed-off-by: Zheng Yongjun <zhengyongjun3@huawei.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-05-11rtnetlink: avoid RCU read lock when holding RTNLCong Wang1-19/+7
When we call af_ops->set_link_af() we hold a RCU read lock as we retrieve af_ops from the RCU protected list, but this is unnecessary because we already hold RTNL lock, which is the writer lock for protecting rtnl_af_ops, so it is safer than RCU read lock. Similar for af_ops->validate_link_af(). This was not a problem until we begin to take mutex lock down the path of ->set_link_af() in __ipv6_dev_mc_dec() recently. We can just drop the RCU read lock there and assert RTNL lock. Reported-and-tested-by: syzbot+7d941e89dd48bcf42573@syzkaller.appspotmail.com Fixes: 63ed8de4be81 ("mld: add mc_lock for protecting per-interface mld data") Tested-by: Taehee Yoo <ap420073@gmail.com> Signed-off-by: Cong Wang <cong.wang@bytedance.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-04-10Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski1-1/+1
Conflicts: MAINTAINERS - keep Chandrasekar drivers/net/ethernet/mellanox/mlx5/core/en_main.c - simple fix + trust the code re-added to param.c in -next is fine include/linux/bpf.h - trivial include/linux/ethtool.h - trivial, fix kdoc while at it include/linux/skmsg.h - move to relevant place in tcp.c, comment re-wrapped net/core/skmsg.c - add the sk = sk // sk = NULL around calls net/tipc/crypto.c - trivial Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-04-08ipv6: report errors for iftoken via netlink extackStephen Hemminger1-1/+1
Setting iftoken can fail for several different reasons but there and there was no report to user as to the cause. Add netlink extended errors to the processing of the request. This requires adding additional argument through rtnl_af_ops set_link_af callback. Reported-by: Hongren Zheng <li@zenithal.me> Signed-off-by: Stephen Hemminger <stephen@networkplumber.org> Reviewed-by: David Ahern <dsahern@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-04-08net: remove the new_ifindex argument from dev_change_net_namespaceAndrei Vagin1-2/+2
Here is only one place where we want to specify new_ifindex. In all other cases, callers pass 0 as new_ifindex. It looks reasonable to add a low-level function with new_ifindex and to convert dev_change_net_namespace to a static inline wrapper. Fixes: eeb85a14ee34 ("net: Allow to specify ifindex when device is moved to another namespace") Suggested-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Andrei Vagin <avagin@gmail.com> Acked-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-04-08net: introduce nla_policy for IFLA_NEW_IFINDEXAndrei Vagin1-3/+1
In this case, we don't need to check that new_ifindex is positive in validate_linkmsg. Fixes: eeb85a14ee34 ("net: Allow to specify ifindex when device is moved to another namespace") Suggested-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Andrei Vagin <avagin@gmail.com> Acked-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-04-06net: Allow to specify ifindex when device is moved to another namespaceAndrei Vagin1-4/+15
Currently, we can specify ifindex on link creation. This change allows to specify ifindex when a device is moved to another network namespace. Even now, a device ifindex can be changed if there is another device with the same ifindex in the target namespace. So this change doesn't introduce completely new behavior, it adds more control to the process. CRIU users want to restore containers with pre-created network devices. A user will provide network devices and instructions where they have to be restored, then CRIU will restore network namespaces and move devices into them. The problem is that devices have to be restored with the same indexes that they have before C/R. Cc: Alexander Mikhalitsyn <alexander.mikhalitsyn@virtuozzo.com> Suggested-by: Christian Brauner <christian.brauner@ubuntu.com> Signed-off-by: Andrei Vagin <avagin@gmail.com> Reviewed-by: Christian Brauner <christian.brauner@ubuntu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-03-04rtnetlink: using dev_base_seq from target netzhang kai1-1/+1
Signed-off-by: zhang kai <zhangkaiheb@126.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-02-12net: fix dev_ifsioc_locked() race conditionCong Wang1-1/+1
dev_ifsioc_locked() is called with only RCU read lock, so when there is a parallel writer changing the mac address, it could get a partially updated mac address, as shown below: Thread 1 Thread 2 // eth_commit_mac_addr_change() memcpy(dev->dev_addr, addr->sa_data, ETH_ALEN); // dev_ifsioc_locked() memcpy(ifr->ifr_hwaddr.sa_data, dev->dev_addr,...); Close this race condition by guarding them with a RW semaphore, like netdev_get_name(). We can not use seqlock here as it does not allow blocking. The writers already take RTNL anyway, so this does not affect the slow path. To avoid bothering existing dev_set_mac_address() callers in drivers, introduce a new wrapper just for user-facing callers on ioctl and rtnetlink paths. Note, bonding also changes slave mac addresses but that requires a separate patch due to the complexity of bonding code. Fixes: 3710becf8a58 ("net: RCU locking for simple ioctl()") Reported-by: "Gong, Sishuai" <sishuai@purdue.edu> Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Cong Wang <cong.wang@bytedance.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-01-28net: bridge: multicast: make tracked EHT hosts limit configurableNikolay Aleksandrov1-1/+1
Add two new port attributes which make EHT hosts limit configurable and export the current number of tracked EHT hosts: - IFLA_BRPORT_MCAST_EHT_HOSTS_LIMIT: configure/retrieve current limit - IFLA_BRPORT_MCAST_EHT_HOSTS_CNT: current number of tracked hosts Setting IFLA_BRPORT_MCAST_EHT_HOSTS_LIMIT to 0 is currently not allowed. Note that we have to increase RTNL_SLAVE_MAX_TYPE to 38 minimum, I've increased it to 40 to have space for two more future entries. v2: move br_multicast_eht_set_hosts_limit() to br_multicast_eht.c, no functional change Signed-off-by: Nikolay Aleksandrov <nikolay@nvidia.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-01-09net: make free_netdev() more lenient with unregistering devicesJakub Kicinski1-17/+6
There are two flavors of handling netdev registration: - ones called without holding rtnl_lock: register_netdev() and unregister_netdev(); and - those called with rtnl_lock held: register_netdevice() and unregister_netdevice(). While the semantics of the former are pretty clear, the same can't be said about the latter. The netdev_todo mechanism is utilized to perform some of the device unregistering tasks and it hooks into rtnl_unlock() so the locked variants can't actually finish the work. In general free_netdev() does not mix well with locked calls. Most drivers operating under rtnl_lock set dev->needs_free_netdev to true and expect core to make the free_netdev() call some time later. The part where this becomes most problematic is error paths. There is no way to unwind the state cleanly after a call to register_netdevice(), since unreg can't be performed fully without dropping locks. Make free_netdev() more lenient, and defer the freeing if device is being unregistered. This allows error paths to simply call free_netdev() both after register_netdevice() failed, and after a call to unregister_netdevice() but before dropping rtnl_lock. Simplify the error paths which are currently doing gymnastics around free_netdev() handling. Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-01-09docs: net: explain struct net_device lifetimeJakub Kicinski1-1/+1
Explain the two basic flows of struct net_device's operation. Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-12-11rtnetlink: RCU-annotate both dimensions of rtnl_msg_handlersJakub Kicinski1-11/+13
We use rcu_assign_pointer to assign both the table and the entries, but the entries are not marked as __rcu. This generates sparse warnings. Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-11-16treewide: rename nla_strlcpy to nla_strscpy.Francis Laniel1-6/+6
Calls to nla_strlcpy are now replaced by calls to nla_strscpy which is the new name of this function. Signed-off-by: Francis Laniel <laniel_francis@privacyrequired.com> Reviewed-by: Kees Cook <keescook@chromium.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-10-22rtnetlink: fix data overflow in rtnl_calcit()Di Zhu1-7/+6
"ip addr show" command execute error when we have a physical network card with a large number of VFs The return value of if_nlmsg_size() in rtnl_calcit() will exceed range of u16 data type when any network cards has a larger number of VFs. rtnl_vfinfo_size() will significant increase needed dump size when the value of num_vfs is larger. Eventually we get a wrong value of min_ifinfo_dump_size because of overflow which decides the memory size needed by netlink dump and netlink_dump() will return -EMSGSIZE because of not enough memory was allocated. So fix it by promoting min_dump_alloc data type to u32 to avoid whole netlink message size overflow and it's also align with the data type of struct netlink_callback{}.min_dump_alloc which is assigned by return value of rtnl_calcit() Signed-off-by: Di Zhu <zhudi21@huawei.com> Link: https://lore.kernel.org/r/20201021020053.1401-1-zhudi21@huawei.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-08-04Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-nextDavid S. Miller1-3/+2
Daniel Borkmann says: ==================== pull-request: bpf-next 2020-08-04 The following pull-request contains BPF updates for your *net-next* tree. We've added 73 non-merge commits during the last 9 day(s) which contain a total of 135 files changed, 4603 insertions(+), 1013 deletions(-). The main changes are: 1) Implement bpf_link support for XDP. Also add LINK_DETACH operation for the BPF syscall allowing processes with BPF link FD to force-detach, from Andrii Nakryiko. 2) Add BPF iterator for map elements and to iterate all BPF programs for efficient in-kernel inspection, from Yonghong Song and Alexei Starovoitov. 3) Separate bpf_get_{stack,stackid}() helpers for perf events in BPF to avoid unwinder errors, from Song Liu. 4) Allow cgroup local storage map to be shared between programs on the same cgroup. Also extend BPF selftests with coverage, from YiFei Zhu. 5) Add BPF exception tables to ARM64 JIT in order to be able to JIT BPF_PROBE_MEM load instructions, from Jean-Philippe Brucker. 6) Follow-up fixes on BPF socket lookup in combination with reuseport group handling. Also add related BPF selftests, from Jakub Sitnicki. 7) Allow to use socket storage in BPF_PROG_TYPE_CGROUP_SOCK-typed programs for socket create/release as well as bind functions, from Stanislav Fomichev. 8) Fix an info leak in xsk_getsockopt() when retrieving XDP stats via old struct xdp_statistics, from Peilin Ye. 9) Fix PT_REGS_RC{,_CORE}() macros in libbpf for MIPS arch, from Jerry Crunchtime. 10) Extend BPF kernel test infra with skb->family and skb->{local,remote}_ip{4,6} fields and allow user space to specify skb->dev via ifindex, from Dmitry Yakunin. 11) Fix a bpftool segfault due to missing program type name and make it more robust to prevent them in future gaps, from Quentin Monnet. 12) Consolidate cgroup helper functions across selftests and fix a v6 localhost resolver issue, from John Fastabend. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2020-08-01rtnetlink: add support for protodown reasonRoopa Prabhu1-5/+108
netdev protodown is a mechanism that allows protocols to hold an interface down. It was initially introduced in the kernel to hold links down by a multihoming protocol. There was also an attempt to introduce protodown reason at the time but was rejected. protodown and protodown reason is supported by almost every switching and routing platform. It was ok for a while to live without a protodown reason. But, its become more critical now given more than one protocol may need to keep a link down on a system at the same time. eg: vrrp peer node, port security, multihoming protocol. Its common for Network operators and protocol developers to look for such a reason on a networking box (Its also known as errDisable by most networking operators) This patch adds support for link protodown reason attribute. There are two ways to maintain protodown reasons. (a) enumerate every possible reason code in kernel - A protocol developer has to make a request and have that appear in a certain kernel version (b) provide the bits in the kernel, and allow user-space (sysadmin or NOS distributions) to manage the bit-to-reasonname map. - This makes extending reason codes easier (kind of like the iproute2 table to vrf-name map /etc/iproute2/rt_tables.d/) This patch takes approach (b). a few things about the patch: - It treats the protodown reason bits as counter to indicate active protodown users - Since protodown attribute is already an exposed UAPI, the reason is not enforced on a protodown set. Its a no-op if not used. the patch follows the below algorithm: - presence of reason bits set indicates protodown is in use - user can set protodown and protodown reason in a single or multiple setlink operations - setlink operation to clear protodown, will return -EBUSY if there are active protodown reason bits - reason is not included in link dumps if not used example with patched iproute2: $cat /etc/iproute2/protodown_reasons.d/r.conf 0 mlag 1 evpn 2 vrrp 3 psecurity $ip link set dev vxlan0 protodown on protodown_reason vrrp on $ip link set dev vxlan0 protodown_reason mlag on $ip link show 14: vxlan0: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000 link/ether f6:06:be:17:91:e7 brd ff:ff:ff:ff:ff:ff protodown on <mlag,vrrp> $ip link set dev vxlan0 protodown_reason mlag off $ip link set dev vxlan0 protodown off protodown_reason vrrp off Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-26bpf, xdp: Maintain info on attached XDP BPF programs in net_deviceAndrii Nakryiko1-3/+2
Instead of delegating to drivers, maintain information about which BPF programs are attached in which XDP modes (generic/skb, driver, or hardware) locally in net_device. This effectively obsoletes XDP_QUERY_PROG command. Such re-organization simplifies existing code already. But it also allows to further add bpf_link-based XDP attachments without drivers having to know about any of this at all, which seems like a good setup. XDP_SETUP_PROG/XDP_SETUP_PROG_HW are just low-level commands to driver to install/uninstall active BPF program. All the higher-level concerns about prog/link interaction will be contained within generic driver-agnostic logic. All the XDP_QUERY_PROG calls to driver in dev_xdp_uninstall() were removed. It's not clear for me why dev_xdp_uninstall() were passing previous prog_flags when resetting installed programs. That seems unnecessary, plus most drivers don't populate prog_flags anyways. Having XDP_SETUP_PROG vs XDP_SETUP_PROG_HW should be enough of an indicator of what is required of driver to correctly reset active BPF program. dev_xdp_uninstall() is also generalized as an iteration over all three supported mode. Signed-off-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20200722064603.3350758-3-andriin@fb.com
2020-07-17rtnetlink: Fix memory(net_device) leak when ->newlink failsWeilong Chen1-1/+2
When vlan_newlink call register_vlan_dev fails, it might return error with dev->reg_state = NETREG_UNREGISTERED. The rtnl_newlink should free the memory. But currently rtnl_newlink only free the memory which state is NETREG_UNINITIALIZED. BUG: memory leak unreferenced object 0xffff8881051de000 (size 4096): comm "syz-executor139", pid 560, jiffies 4294745346 (age 32.445s) hex dump (first 32 bytes): 76 6c 61 6e 32 00 00 00 00 00 00 00 00 00 00 00 vlan2........... 00 45 28 03 81 88 ff ff 00 00 00 00 00 00 00 00 .E(............. backtrace: [<0000000047527e31>] kmalloc_node include/linux/slab.h:578 [inline] [<0000000047527e31>] kvmalloc_node+0x33/0xd0 mm/util.c:574 [<000000002b59e3bc>] kvmalloc include/linux/mm.h:753 [inline] [<000000002b59e3bc>] kvzalloc include/linux/mm.h:761 [inline] [<000000002b59e3bc>] alloc_netdev_mqs+0x83/0xd90 net/core/dev.c:9929 [<000000006076752a>] rtnl_create_link+0x2c0/0xa20 net/core/rtnetlink.c:3067 [<00000000572b3be5>] __rtnl_newlink+0xc9c/0x1330 net/core/rtnetlink.c:3329 [<00000000e84ea553>] rtnl_newlink+0x66/0x90 net/core/rtnetlink.c:3397 [<0000000052c7c0a9>] rtnetlink_rcv_msg+0x540/0x990 net/core/rtnetlink.c:5460 [<000000004b5cb379>] netlink_rcv_skb+0x12b/0x3a0 net/netlink/af_netlink.c:2469 [<00000000c71c20d3>] netlink_unicast_kernel net/netlink/af_netlink.c:1303 [inline] [<00000000c71c20d3>] netlink_unicast+0x4c6/0x690 net/netlink/af_netlink.c:1329 [<00000000cca72fa9>] netlink_sendmsg+0x735/0xcc0 net/netlink/af_netlink.c:1918 [<000000009221ebf7>] sock_sendmsg_nosec net/socket.c:652 [inline] [<000000009221ebf7>] sock_sendmsg+0x109/0x140 net/socket.c:672 [<000000001c30ffe4>] ____sys_sendmsg+0x5f5/0x780 net/socket.c:2352 [<00000000b71ca6f3>] ___sys_sendmsg+0x11d/0x1a0 net/socket.c:2406 [<0000000007297384>] __sys_sendmsg+0xeb/0x1b0 net/socket.c:2439 [<000000000eb29b11>] do_syscall_64+0x56/0xa0 arch/x86/entry/common.c:359 [<000000006839b4d0>] entry_SYSCALL_64_after_hwframe+0x44/0xa9 Fixes: cb626bf566eb ("net-sysfs: Fix reference count leak") Reported-by: Hulk Robot <hulkci@huawei.com> Signed-off-by: Weilong Chen <chenweilong@huawei.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-06-09net: change addr_list_lock back to static keyCong Wang1-1/+0
The dynamic key update for addr_list_lock still causes troubles, for example the following race condition still exists: CPU 0: CPU 1: (RCU read lock) (RTNL lock) dev_mc_seq_show() netdev_update_lockdep_key() -> lockdep_unregister_key() -> netif_addr_lock_bh() because lockdep doesn't provide an API to update it atomically. Therefore, we have to move it back to static keys and use subclass for nest locking like before. In commit 1a33e10e4a95 ("net: partially revert dynamic lockdep key changes"), I already reverted most parts of commit ab92d68fc22f ("net: core: add generic lockdep keys"). This patch reverts the rest and also part of commit f3b0a18bb6cb ("net: remove unnecessary variables and callback"). After this patch, addr_list_lock changes back to using static keys and subclasses to satisfy lockdep. Thanks to dev->lower_level, we do not have to change back to ->ndo_get_lock_subclass(). And hopefully this reduces some syzbot lockdep noises too. Reported-by: syzbot+f3a0e80c34b3fc28ac5e@syzkaller.appspotmail.com Cc: Taehee Yoo <ap420073@gmail.com> Cc: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-04-27net: rtnetlink: remove redundant assignment to variable errColin Ian King1-1/+1
The variable err is being initializeed with a value that is never read and it is being updated later with a new value. The initialization is redundant and can be removed. Addresses-Coverity: ("Unused value") Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-04-20net: Add IF_OPER_TESTINGAndrew Lunn1-1/+8
RFC 2863 defines the operational state testing. Add support for this state, both as a IF_LINK_MODE_ and __LINK_STATE_. Signed-off-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-03-29xdp: Support specifying expected existing program when attaching XDPToke Høiland-Jørgensen1-0/+14
While it is currently possible for userspace to specify that an existing XDP program should not be replaced when attaching to an interface, there is no mechanism to safely replace a specific XDP program with another. This patch adds a new netlink attribute, IFLA_XDP_EXPECTED_FD, which can be set along with IFLA_XDP_FD. If set, the kernel will check that the program currently loaded on the interface matches the expected one, and fail the operation if it does not. This corresponds to a 'cmpxchg' memory operation. Setting the new attribute with a negative value means that no program is expected to be attached, which corresponds to setting the UPDATE_IF_NOEXIST flag. A new companion flag, XDP_FLAGS_REPLACE, is also added to explicitly request checking of the EXPECTED_FD attribute. This is needed for userspace to discover whether the kernel supports the new attribute. Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Reviewed-by: Jakub Kicinski <kuba@kernel.org> Link: https://lore.kernel.org/bpf/158515700640.92963.3551295145441017022.stgit@toke.dk
2020-02-22Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netDavid S. Miller1-14/+12
Conflict resolution of ice_virtchnl_pf.c based upon work by Stephen Rothwell. Signed-off-by: David S. Miller <davem@davemloft.net>
2020-02-20net: use netif_is_bridge_port() to check for IFF_BRIDGE_PORTJulian Wiedmann1-6/+6
Trivial cleanup, so that all bridge port-specific code can be found in one go. CC: Johannes Berg <johannes@sipsolutions.net> CC: Roopa Prabhu <roopa@cumulusnetworks.com> CC: Nikolay Aleksandrov <nikolay@cumulusnetworks.com> Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com> Reviewed-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-02-18net: bridge: teach ndo_dflt_bridge_getlink() more brport flagsJulian Wiedmann1-1/+5
This enables ndo_dflt_bridge_getlink() to report a bridge port's offload settings for multicast and broadcast flooding. CC: Roopa Prabhu <roopa@cumulusnetworks.com> CC: Nikolay Aleksandrov <nikolay@cumulusnetworks.com> Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>