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2019-10-20Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netDavid S. Miller70-378/+579
Several cases of overlapping changes which were for the most part trivially resolvable. Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-19Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netLinus Torvalds68-362/+564
Pull networking fixes from David Miller: "I was battling a cold after some recent trips, so quite a bit piled up meanwhile, sorry about that. Highlights: 1) Fix fd leak in various bpf selftests, from Brian Vazquez. 2) Fix crash in xsk when device doesn't support some methods, from Magnus Karlsson. 3) Fix various leaks and use-after-free in rxrpc, from David Howells. 4) Fix several SKB leaks due to confusion of who owns an SKB and who should release it in the llc code. From Eric Biggers. 5) Kill a bunc of KCSAN warnings in TCP, from Eric Dumazet. 6) Jumbo packets don't work after resume on r8169, as the BIOS resets the chip into non-jumbo mode during suspend. From Heiner Kallweit. 7) Corrupt L2 header during MPLS push, from Davide Caratti. 8) Prevent possible infinite loop in tc_ctl_action, from Eric Dumazet. 9) Get register bits right in bcmgenet driver, based upon chip version. From Florian Fainelli. 10) Fix mutex problems in microchip DSA driver, from Marek Vasut. 11) Cure race between route lookup and invalidation in ipv4, from Wei Wang. 12) Fix performance regression due to false sharing in 'net' structure, from Eric Dumazet" * git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (145 commits) net: reorder 'struct net' fields to avoid false sharing net: dsa: fix switch tree list net: ethernet: dwmac-sun8i: show message only when switching to promisc net: aquantia: add an error handling in aq_nic_set_multicast_list net: netem: correct the parent's backlog when corrupted packet was dropped net: netem: fix error path for corrupted GSO frames macb: propagate errors when getting optional clocks xen/netback: fix error path of xenvif_connect_data() net: hns3: fix mis-counting IRQ vector numbers issue net: usb: lan78xx: Connect PHY before registering MAC vsock/virtio: discard packets if credit is not respected vsock/virtio: send a credit update when buffer size is changed mlxsw: spectrum_trap: Push Ethernet header before reporting trap net: ensure correct skb->tstamp in various fragmenters net: bcmgenet: reset 40nm EPHY on energy detect net: bcmgenet: soft reset 40nm EPHYs before MAC init net: phy: bcm7xxx: define soft_reset for 40nm EPHY net: bcmgenet: don't set phydev->link from MAC net: Update address for MediaTek ethernet driver in MAINTAINERS ipv4: fix race condition between route lookup and invalidation ...
2019-10-19net: dsa: fix switch tree listVivien Didelot1-1/+1
If there are multiple switch trees on the device, only the last one will be listed, because the arguments of list_add_tail are swapped. Fixes: 83c0afaec7b7 ("net: dsa: Add new binding implementation") Signed-off-by: Vivien Didelot <vivien.didelot@gmail.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-19net: netem: correct the parent's backlog when corrupted packet was droppedJakub Kicinski1-0/+2
If packet corruption failed we jump to finish_segs and return NET_XMIT_SUCCESS. Seeing success will make the parent qdisc increment its backlog, that's incorrect - we need to return NET_XMIT_DROP. Fixes: 6071bd1aa13e ("netem: Segment GSO packets on enqueue") Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Simon Horman <simon.horman@netronome.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-19net: netem: fix error path for corrupted GSO framesJakub Kicinski1-3/+6
To corrupt a GSO frame we first perform segmentation. We then proceed using the first segment instead of the full GSO skb and requeue the rest of the segments as separate packets. If there are any issues with processing the first segment we still want to process the rest, therefore we jump to the finish_segs label. Commit 177b8007463c ("net: netem: fix backlog accounting for corrupted GSO frames") started using the pointer to the first segment in the "rest of segments processing", but as mentioned above the first segment may had already been freed at this point. Backlog corrections for parent qdiscs have to be adjusted. Fixes: 177b8007463c ("net: netem: fix backlog accounting for corrupted GSO frames") Reported-by: kbuild test robot <lkp@intel.com> Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Reported-by: Ben Hutchings <ben@decadent.org.uk> Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Simon Horman <simon.horman@netronome.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-18vsock/virtio: discard packets if credit is not respectedStefano Garzarella1-3/+11
If the remote peer doesn't respect the credit information (buf_alloc, fwd_cnt), sending more data than it can send, we should drop the packets to prevent a malicious peer from using all of our memory. This is patch follows the VIRTIO spec: "VIRTIO_VSOCK_OP_RW data packets MUST only be transmitted when the peer has sufficient free buffer space for the payload" Signed-off-by: Stefano Garzarella <sgarzare@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-18vsock/virtio: send a credit update when buffer size is changedStefano Garzarella1-0/+3
When the user application set a new buffer size value, we should update the remote peer about this change, since it uses this information to calculate the credit available. Signed-off-by: Stefano Garzarella <sgarzare@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-18net: ensure correct skb->tstamp in various fragmentersEric Dumazet4-0/+12
Thomas found that some forwarded packets would be stuck in FQ packet scheduler because their skb->tstamp contained timestamps far in the future. We thought we addressed this point in commit 8203e2d844d3 ("net: clear skb->tstamp in forwarding paths") but there is still an issue when/if a packet needs to be fragmented. In order to meet EDT requirements, we have to make sure all fragments get the original skb->tstamp. Note that this original skb->tstamp should be zero in forwarding path, but might have a non zero value in output path if user decided so. Fixes: fb420d5d91c1 ("tcp/fq: move back to CLOCK_MONOTONIC") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Thomas Bartschies <Thomas.Bartschies@cvk.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-17ipv4: fix race condition between route lookup and invalidationWei Wang1-1/+1
Jesse and Ido reported the following race condition: <CPU A, t0> - Received packet A is forwarded and cached dst entry is taken from the nexthop ('nhc->nhc_rth_input'). Calls skb_dst_set() <t1> - Given Jesse has busy routers ("ingesting full BGP routing tables from multiple ISPs"), route is added / deleted and rt_cache_flush() is called <CPU B, t2> - Received packet B tries to use the same cached dst entry from t0, but rt_cache_valid() is no longer true and it is replaced in rt_cache_route() by the newer one. This calls dst_dev_put() on the original dst entry which assigns the blackhole netdev to 'dst->dev' <CPU A, t3> - dst_input(skb) is called on packet A and it is dropped due to 'dst->dev' being the blackhole netdev There are 2 issues in the v4 routing code: 1. A per-netns counter is used to do the validation of the route. That means whenever a route is changed in the netns, users of all routes in the netns needs to redo lookup. v6 has an implementation of only updating fn_sernum for routes that are affected. 2. When rt_cache_valid() returns false, rt_cache_route() is called to throw away the current cache, and create a new one. This seems unnecessary because as long as this route does not change, the route cache does not need to be recreated. To fully solve the above 2 issues, it probably needs quite some code changes and requires careful testing, and does not suite for net branch. So this patch only tries to add the deleted cached rt into the uncached list, so user could still be able to use it to receive packets until it's done. Fixes: 95c47f9cf5e0 ("ipv4: call dst_dev_put() properly") Signed-off-by: Wei Wang <weiwan@google.com> Reported-by: Ido Schimmel <idosch@idosch.org> Reported-by: Jesse Hathaway <jesse@mbuki-mvuki.org> Tested-by: Jesse Hathaway <jesse@mbuki-mvuki.org> Acked-by: Martin KaFai Lau <kafai@fb.com> Cc: David Ahern <dsahern@gmail.com> Reviewed-by: Ido Schimmel <idosch@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-17ipv4: Return -ENETUNREACH if we can't create route but saddr is validStefano Brivio1-3/+6
...instead of -EINVAL. An issue was found with older kernel versions while unplugging a NFS client with pending RPCs, and the wrong error code here prevented it from recovering once link is back up with a configured address. Incidentally, this is not an issue anymore since commit 4f8943f80883 ("SUNRPC: Replace direct task wakeups from softirq context"), included in 5.2-rc7, had the effect of decoupling the forwarding of this error by using SO_ERROR in xs_wake_error(), as pointed out by Benjamin Coddington. To the best of my knowledge, this isn't currently causing any further issue, but the error code doesn't look appropriate anyway, and we might hit this in other paths as well. In detail, as analysed by Gonzalo Siero, once the route is deleted because the interface is down, and can't be resolved and we return -EINVAL here, this ends up, courtesy of inet_sk_rebuild_header(), as the socket error seen by tcp_write_err(), called by tcp_retransmit_timer(). In turn, tcp_write_err() indirectly calls xs_error_report(), which wakes up the RPC pending tasks with a status of -EINVAL. This is then seen by call_status() in the SUN RPC implementation, which aborts the RPC call calling rpc_exit(), instead of handling this as a potentially temporary condition, i.e. as a timeout. Return -EINVAL only if the input parameters passed to ip_route_output_key_hash_rcu() are actually invalid (this is the case if the specified source address is multicast, limited broadcast or all zeroes), but return -ENETUNREACH in all cases where, at the given moment, the given source address doesn't allow resolving the route. While at it, drop the initialisation of err to -ENETUNREACH, which was added to __ip_route_output_key() back then by commit 0315e3827048 ("net: Fix behaviour of unreachable, blackhole and prohibit routes"), but actually had no effect, as it was, and is, overwritten by the fib_lookup() return code assignment, and anyway ignored in all other branches, including the if (fl4->saddr) one: I find this rather confusing, as it would look like -ENETUNREACH is the "default" error, while that statement has no effect. Also note that after commit fc75fc8339e7 ("ipv4: dont create routes on down devices"), we would get -ENETUNREACH if the device is down, but -EINVAL if the source address is specified and we can't resolve the route, and this appears to be rather inconsistent. Reported-by: Stefan Walter <walteste@inf.ethz.ch> Analysed-by: Benjamin Coddington <bcodding@redhat.com> Analysed-by: Gonzalo Siero <gsierohu@redhat.com> Signed-off-by: Stefano Brivio <sbrivio@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-17net: sched: Avoid using yield() in a busy waiting loopMarc Kleine-Budde1-2/+7
With threaded interrupts enabled, the interrupt thread runs as SCHED_RR with priority 50. If a user application with a higher priority preempts the interrupt thread and tries to shutdown the network interface then it will loop forever. The kernel will spin in the loop waiting for the device to become idle and the scheduler will never consider the interrupt thread because its priority is lower. Avoid the problem by sleeping for a jiffy giving other tasks, including the interrupt thread, a chance to run and make progress. In the original thread it has been suggested to use wait_event() and properly waiting for the state to occur. DaveM explained that this would require to add expensive checks in the fast paths of packet processing. Link: https://lkml.kernel.org/r/1393976987-23555-1-git-send-email-mkl@pengutronix.de Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de> [bigeasy: Rewrite commit message, add comment, use schedule_timeout_uninterruptible()] Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Acked-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-17net/rds: Remove unnecessary null checkYueHaibing1-2/+1
Null check before dma_pool_destroy is redundant, so remove it. This is detected by coccinelle. Signed-off-by: YueHaibing <yuehaibing@huawei.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-17pktgen: remove unnecessary assignment in pktgen_xmit()Yunsheng Lin1-1/+0
variable ret is not used after jumping to "unlock" label, so the assignment is redundant. Signed-off-by: Yunsheng Lin <linyunsheng@huawei.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-16rxrpc: use rcu protection while reading sk->sk_user_dataEric Dumazet1-4/+8
We need to extend the rcu_read_lock() section in rxrpc_error_report() and use rcu_dereference_sk_user_data() instead of plain access to sk->sk_user_data to make sure all rules are respected. The compiler wont reload sk->sk_user_data at will, and RCU rules prevent memory beeing freed too soon. Fixes: f0308fb07080 ("rxrpc: Fix possible NULL pointer access in ICMP handling") Fixes: 17926a79320a ("[AF_RXRPC]: Provide secure RxRPC sockets for use by userspace and kernel both") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-16Revert "blackhole_netdev: fix syzkaller reported issue"Mahesh Bandewar2-12/+10
This reverts commit b0818f80c8c1bc215bba276bd61c216014fab23b. Started seeing weird behavior after this patch especially in the IPv6 code path. Haven't root caused it, but since this was applied to net branch, taking a precautionary measure to revert it and look / analyze those failures Revert this now and I'll send a better fix after analysing / fixing the weirdness observed. CC: Eric Dumazet <edumazet@google.com> CC: Wei Wang <weiwan@google.com> CC: David S. Miller <davem@davemloft.net> Signed-off-by: Mahesh Bandewar <maheshb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-15sctp: change sctp_prot .no_autobind with trueXin Long1-2/+2
syzbot reported a memory leak: BUG: memory leak, unreferenced object 0xffff888120b3d380 (size 64): backtrace: [...] slab_alloc mm/slab.c:3319 [inline] [...] kmem_cache_alloc+0x13f/0x2c0 mm/slab.c:3483 [...] sctp_bucket_create net/sctp/socket.c:8523 [inline] [...] sctp_get_port_local+0x189/0x5a0 net/sctp/socket.c:8270 [...] sctp_do_bind+0xcc/0x200 net/sctp/socket.c:402 [...] sctp_bindx_add+0x4b/0xd0 net/sctp/socket.c:497 [...] sctp_setsockopt_bindx+0x156/0x1b0 net/sctp/socket.c:1022 [...] sctp_setsockopt net/sctp/socket.c:4641 [inline] [...] sctp_setsockopt+0xaea/0x2dc0 net/sctp/socket.c:4611 [...] sock_common_setsockopt+0x38/0x50 net/core/sock.c:3147 [...] __sys_setsockopt+0x10f/0x220 net/socket.c:2084 [...] __do_sys_setsockopt net/socket.c:2100 [inline] It was caused by when sending msgs without binding a port, in the path: inet_sendmsg() -> inet_send_prepare() -> inet_autobind() -> .get_port/sctp_get_port(), sp->bind_hash will be set while bp->port is not. Later when binding another port by sctp_setsockopt_bindx(), a new bucket will be created as bp->port is not set. sctp's autobind is supposed to call sctp_autobind() where it does all things including setting bp->port. Since sctp_autobind() is called in sctp_sendmsg() if the sk is not yet bound, it should have skipped the auto bind. THis patch is to avoid calling inet_autobind() in inet_send_prepare() by changing sctp_prot .no_autobind with true, also remove the unused .get_port. Reported-by: syzbot+d44f7bbebdea49dbc84a@syzkaller.appspotmail.com Signed-off-by: Xin Long <lucien.xin@gmail.com> Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-15sched: etf: Fix ordering of packets with same txtimeVinicius Costa Gomes1-1/+1
When a application sends many packets with the same txtime, they may be transmitted out of order (different from the order in which they were enqueued). This happens because when inserting elements into the tree, when the txtime of two packets are the same, the new packet is inserted at the left side of the tree, causing the reordering. The only effect of this change should be that packets with the same txtime will be transmitted in the order they are enqueued. The application in question (the AVTP GStreamer plugin, still in development) is sending video traffic, in which each video frame have a single presentation time, the problem is that when packetizing, multiple packets end up with the same txtime. The receiving side was rejecting packets because they were being received out of order. Fixes: 25db26a91364 ("net/sched: Introduce the ETF Qdisc") Reported-by: Ederson de Souza <ederson.desouza@intel.com> Signed-off-by: Vinicius Costa Gomes <vinicius.gomes@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-15net: avoid potential infinite loop in tc_ctl_action()Eric Dumazet1-6/+8
tc_ctl_action() has the ability to loop forever if tcf_action_add() returns -EAGAIN. This special case has been done in case a module needed to be loaded, but it turns out that tcf_add_notify() could also return -EAGAIN if the socket sk_rcvbuf limit is hit. We need to separate the two cases, and only loop for the module loading case. While we are at it, add a limit of 10 attempts since unbounded loops are always scary. syzbot repro was something like : socket(PF_NETLINK, SOCK_RAW|SOCK_NONBLOCK, NETLINK_ROUTE) = 3 write(3, ..., 38) = 38 setsockopt(3, SOL_SOCKET, SO_RCVBUF, [0], 4) = 0 sendmsg(3, {msg_name(0)=NULL, msg_iov(1)=[{..., 388}], msg_controllen=0, msg_flags=0x10}, ...) NMI backtrace for cpu 0 CPU: 0 PID: 1054 Comm: khungtaskd Not tainted 5.4.0-rc1+ #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x172/0x1f0 lib/dump_stack.c:113 nmi_cpu_backtrace.cold+0x70/0xb2 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x23b/0x28b lib/nmi_backtrace.c:62 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:205 [inline] watchdog+0x9d0/0xef0 kernel/hung_task.c:289 kthread+0x361/0x430 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 8859 Comm: syz-executor910 Not tainted 5.4.0-rc1+ #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:arch_local_save_flags arch/x86/include/asm/paravirt.h:751 [inline] RIP: 0010:lockdep_hardirqs_off+0x1df/0x2e0 kernel/locking/lockdep.c:3453 Code: 5c 08 00 00 5b 41 5c 41 5d 5d c3 48 c7 c0 58 1d f3 88 48 ba 00 00 00 00 00 fc ff df 48 c1 e8 03 80 3c 10 00 0f 85 d3 00 00 00 <48> 83 3d 21 9e 99 07 00 0f 84 b9 00 00 00 9c 58 0f 1f 44 00 00 f6 RSP: 0018:ffff8880a6f3f1b8 EFLAGS: 00000046 RAX: 1ffffffff11e63ab RBX: ffff88808c9c6080 RCX: 0000000000000000 RDX: dffffc0000000000 RSI: 0000000000000000 RDI: ffff88808c9c6914 RBP: ffff8880a6f3f1d0 R08: ffff88808c9c6080 R09: fffffbfff16be5d1 R10: fffffbfff16be5d0 R11: 0000000000000003 R12: ffffffff8746591f R13: ffff88808c9c6080 R14: ffffffff8746591f R15: 0000000000000003 FS: 00000000011e4880(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffff600400 CR3: 00000000a8920000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: trace_hardirqs_off+0x62/0x240 kernel/trace/trace_preemptirq.c:45 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:108 [inline] _raw_spin_lock_irqsave+0x6f/0xcd kernel/locking/spinlock.c:159 __wake_up_common_lock+0xc8/0x150 kernel/sched/wait.c:122 __wake_up+0xe/0x10 kernel/sched/wait.c:142 netlink_unlock_table net/netlink/af_netlink.c:466 [inline] netlink_unlock_table net/netlink/af_netlink.c:463 [inline] netlink_broadcast_filtered+0x705/0xb80 net/netlink/af_netlink.c:1514 netlink_broadcast+0x3a/0x50 net/netlink/af_netlink.c:1534 rtnetlink_send+0xdd/0x110 net/core/rtnetlink.c:714 tcf_add_notify net/sched/act_api.c:1343 [inline] tcf_action_add+0x243/0x370 net/sched/act_api.c:1362 tc_ctl_action+0x3b5/0x4bc net/sched/act_api.c:1410 rtnetlink_rcv_msg+0x463/0xb00 net/core/rtnetlink.c:5386 netlink_rcv_skb+0x177/0x450 net/netlink/af_netlink.c:2477 rtnetlink_rcv+0x1d/0x30 net/core/rtnetlink.c:5404 netlink_unicast_kernel net/netlink/af_netlink.c:1302 [inline] netlink_unicast+0x531/0x710 net/netlink/af_netlink.c:1328 netlink_sendmsg+0x8a5/0xd60 net/netlink/af_netlink.c:1917 sock_sendmsg_nosec net/socket.c:637 [inline] sock_sendmsg+0xd7/0x130 net/socket.c:657 ___sys_sendmsg+0x803/0x920 net/socket.c:2311 __sys_sendmsg+0x105/0x1d0 net/socket.c:2356 __do_sys_sendmsg net/socket.c:2365 [inline] __se_sys_sendmsg net/socket.c:2363 [inline] __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2363 do_syscall_64+0xfa/0x760 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x440939 Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot+cf0adbb9c28c8866c788@syzkaller.appspotmail.com Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-15net_sched: sch_fq: remove one obsolete check in fq_dequeue()Eric Dumazet1-2/+1
After commit eeb84aa0d0aff ("net_sched: sch_fq: do not assume EDT packets are ordered"), all skbs get a non zero time_to_send in flow_queue_add() This means @time_next_packet variable in fq_dequeue() can no longer be zero. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-15tcp: fix a possible lockdep splat in tcp_done()Eric Dumazet1-2/+6
syzbot found that if __inet_inherit_port() returns an error, we call tcp_done() after inet_csk_prepare_forced_close(), meaning the socket lock is no longer held. We might fix this in a different way in net-next, but for 5.4 it seems safer to relax the lockdep check. Fixes: d983ea6f16b8 ("tcp: add rcu protection around tp->fastopen_rsk") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-15net: core: use listified Rx for GRO_NORMAL in napi_gro_receive()Alexander Lobakin1-24/+25
Commit 323ebb61e32b4 ("net: use listified RX for handling GRO_NORMAL skbs") made use of listified skb processing for the users of napi_gro_frags(). The same technique can be used in a way more common napi_gro_receive() to speed up non-merged (GRO_NORMAL) skbs for a wide range of drivers including gro_cells and mac80211 users. This slightly changes the return value in cases where skb is being dropped by the core stack, but it seems to have no impact on related drivers' functionality. gro_normal_batch is left untouched as it's very individual for every single system configuration and might be tuned in manual order to achieve an optimal performance. Signed-off-by: Alexander Lobakin <alobakin@dlink.ru> Acked-by: Edward Cree <ecree@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-15hv_sock: use HV_HYP_PAGE_SIZE for Hyper-V communicationHimadri Pandya1-10/+12
Current code assumes PAGE_SIZE (the guest page size) is equal to the page size used to communicate with Hyper-V (which is always 4K). While this assumption is true on x86, it may not be true for Hyper-V on other architectures. For example, Linux on ARM64 may have PAGE_SIZE of 16K or 64K. A new symbol, HV_HYP_PAGE_SIZE, has been previously introduced to use when the Hyper-V page size is intended instead of the guest page size. Make this code work on non-x86 architectures by using the new HV_HYP_PAGE_SIZE symbol instead of PAGE_SIZE, where appropriate. Also replace the now redundant PAGE_SIZE_4K with HV_HYP_PAGE_SIZE. The change has no effect on x86, but lays the groundwork to run on ARM64 and others. Signed-off-by: Himadri Pandya <himadrispandya@gmail.com> Reviewed-by: Michael Kelley <mikelley@microsoft.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-15net/sched: fix corrupted L2 header with MPLS 'push' and 'pop' actionsDavide Caratti3-14/+22
the following script: # tc qdisc add dev eth0 clsact # tc filter add dev eth0 egress protocol ip matchall \ > action mpls push protocol mpls_uc label 0x355aa bos 1 causes corruption of all IP packets transmitted by eth0. On TC egress, we can't rely on the value of skb->mac_len, because it's 0 and a MPLS 'push' operation will result in an overwrite of the first 4 octets in the packet L2 header (e.g. the Destination Address if eth0 is an Ethernet); the same error pattern is present also in the MPLS 'pop' operation. Fix this error in act_mpls data plane, computing 'mac_len' as the difference between the network header and the mac header (when not at TC ingress), and use it in MPLS 'push'/'pop' core functions. v2: unbreak 'make htmldocs' because of missing documentation of 'mac_len' in skb_mpls_pop(), reported by kbuild test robot CC: Lorenzo Bianconi <lorenzo@kernel.org> Fixes: 2a2ea50870ba ("net: sched: add mpls manipulation actions to TC") Reviewed-by: Simon Horman <simon.horman@netronome.com> Acked-by: John Hurley <john.hurley@netronome.com> Signed-off-by: Davide Caratti <dcaratti@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-15net: avoid errors when trying to pop MLPS header on non-MPLS packetsDavide Caratti1-1/+1
the following script: # tc qdisc add dev eth0 clsact # tc filter add dev eth0 egress matchall action mpls pop implicitly makes the kernel drop all packets transmitted by eth0, if they don't have a MPLS header. This behavior is uncommon: other encapsulations (like VLAN) just let the packet pass unmodified. Since the result of MPLS 'pop' operation would be the same regardless of the presence / absence of MPLS header(s) in the original packet, we can let skb_mpls_pop() return 0 when dealing with non-MPLS packets. For the OVS use-case, this is acceptable because __ovs_nla_copy_actions() already ensures that MPLS 'pop' operation only occurs with packets having an MPLS Ethernet type (and there are no other callers in current code, so the semantic change should be ok). v2: better documentation of use-cases for skb_mpls_pop(), thanks to Simon Horman Fixes: 2a2ea50870ba ("net: sched: add mpls manipulation actions to TC") Reviewed-by: Simon Horman <simon.horman@netronome.com> Acked-by: John Hurley <john.hurley@netronome.com> Signed-off-by: Davide Caratti <dcaratti@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-15blackhole_netdev: fix syzkaller reported issueMahesh Bandewar2-10/+12
While invalidating the dst, we assign backhole_netdev instead of loopback device. However, this device does not have idev pointer and hence no ip6_ptr even if IPv6 is enabled. Possibly this has triggered the syzbot reported crash. The syzbot report does not have reproducer, however, this is the only device that doesn't have matching idev created. Crash instruction is : static inline bool ip6_ignore_linkdown(const struct net_device *dev) { const struct inet6_dev *idev = __in6_dev_get(dev); return !!idev->cnf.ignore_routes_with_linkdown; <= crash } Also ipv6 always assumes presence of idev and never checks for it being NULL (as does the above referenced code). So adding a idev for the blackhole_netdev to avoid this class of crashes in the future. Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-14Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-nextDavid S. Miller2-7/+41
Alexei Starovoitov says: ==================== pull-request: bpf-next 2019-10-14 The following pull-request contains BPF updates for your *net-next* tree. 12 days of development and 85 files changed, 1889 insertions(+), 1020 deletions(-) The main changes are: 1) auto-generation of bpf_helper_defs.h, from Andrii. 2) split of bpf_helpers.h into bpf_{helpers, helper_defs, endian, tracing}.h and move into libbpf, from Andrii. 3) Track contents of read-only maps as scalars in the verifier, from Andrii. 4) small x86 JIT optimization, from Daniel. 5) cross compilation support, from Ivan. 6) bpf flow_dissector enhancements, from Jakub and Stanislav. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-13Merge tag 'mac80211-next-for-net-next-2019-10-11' of git://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211-nextDavid S. Miller10-92/+143
Johannes Berg says: ==================== A few more small things, nothing really stands out: * minstrel improvements from Felix * a TX aggregation simplification * some additional capabilities for hwsim * minor cleanups & docs updates ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-13genetlink: do not parse attributes for families with zero maxattrMichal Kubecek1-6/+4
Commit c10e6cf85e7d ("net: genetlink: push attrbuf allocation and parsing to a separate function") moved attribute buffer allocation and attribute parsing from genl_family_rcv_msg_doit() into a separate function genl_family_rcv_msg_attrs_parse() which, unlike the previous code, calls __nlmsg_parse() even if family->maxattr is 0 (i.e. the family does its own parsing). The parser error is ignored and does not propagate out of genl_family_rcv_msg_attrs_parse() but an error message ("Unknown attribute type") is set in extack and if further processing generates no error or warning, it stays there and is interpreted as a warning by userspace. Dumpit requests are not affected as genl_family_rcv_msg_dumpit() bypasses the call of genl_family_rcv_msg_attrs_parse() if family->maxattr is zero. Move this logic inside genl_family_rcv_msg_attrs_parse() so that we don't have to handle it in each caller. v3: put the check inside genl_family_rcv_msg_attrs_parse() v2: adjust also argument of genl_family_rcv_msg_attrs_free() Fixes: c10e6cf85e7d ("net: genetlink: push attrbuf allocation and parsing to a separate function") Signed-off-by: Michal Kubecek <mkubecek@suse.cz> Acked-by: Jiri Pirko <jiri@mellanox.com> Acked-by: Jakub Kicinski <jakub.kicinski@netronome.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-13tcp: improve recv_skip_hint for tcp_zerocopy_receiveSoheil Hassas Yeganeh1-5/+5
tcp_zerocopy_receive() rounds down the zc->length a multiple of PAGE_SIZE. This results in two issues: - tcp_zerocopy_receive sets recv_skip_hint to the length of the receive queue if the zc->length input is smaller than the PAGE_SIZE, even though the data in receive queue could be zerocopied. - tcp_zerocopy_receive would set recv_skip_hint of 0, in cases where we have a little bit of data after the perfectly-sized packets. To fix these issues, do not store the rounded down value in zc->length. Round down the length passed to zap_page_range(), and return min(inq, zc->length) when the zap_range is 0. Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-13tcp: annotate sk->sk_wmem_queued lockless readsEric Dumazet6-13/+13
For the sake of tcp_poll(), there are few places where we fetch sk->sk_wmem_queued while this field can change from IRQ or other cpu. We need to add READ_ONCE() annotations, and also make sure write sides use corresponding WRITE_ONCE() to avoid store-tearing. sk_wmem_queued_add() helper is added so that we can in the future convert to ADD_ONCE() or equivalent if/when available. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-13tcp: annotate sk->sk_sndbuf lockless readsEric Dumazet4-9/+14
For the sake of tcp_poll(), there are few places where we fetch sk->sk_sndbuf while this field can change from IRQ or other cpu. We need to add READ_ONCE() annotations, and also make sure write sides use corresponding WRITE_ONCE() to avoid store-tearing. Note that other transports probably need similar fixes. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-13tcp: annotate sk->sk_rcvbuf lockless readsEric Dumazet5-9/+12
For the sake of tcp_poll(), there are few places where we fetch sk->sk_rcvbuf while this field can change from IRQ or other cpu. We need to add READ_ONCE() annotations, and also make sure write sides use corresponding WRITE_ONCE() to avoid store-tearing. Note that other transports probably need similar fixes. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-13tcp: annotate tp->urg_seq lockless readsEric Dumazet2-3/+4
There two places where we fetch tp->urg_seq while this field can change from IRQ or other cpu. We need to add READ_ONCE() annotations, and also make sure write side use corresponding WRITE_ONCE() to avoid store-tearing. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-13tcp: annotate tp->snd_nxt lockless readsEric Dumazet3-8/+11
There are few places where we fetch tp->snd_nxt while this field can change from IRQ or other cpu. We need to add READ_ONCE() annotations, and also make sure write sides use corresponding WRITE_ONCE() to avoid store-tearing. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-13tcp: annotate tp->write_seq lockless readsEric Dumazet6-27/+35
There are few places where we fetch tp->write_seq while this field can change from IRQ or other cpu. We need to add READ_ONCE() annotations, and also make sure write sides use corresponding WRITE_ONCE() to avoid store-tearing. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-13tcp: annotate tp->copied_seq lockless readsEric Dumazet7-18/+19
There are few places where we fetch tp->copied_seq while this field can change from IRQ or other cpu. We need to add READ_ONCE() annotations, and also make sure write sides use corresponding WRITE_ONCE() to avoid store-tearing. Note that tcp_inq_hint() was already using READ_ONCE(tp->copied_seq) Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-13tcp: annotate tp->rcv_nxt lockless readsEric Dumazet6-10/+15
There are few places where we fetch tp->rcv_nxt while this field can change from IRQ or other cpu. We need to add READ_ONCE() annotations, and also make sure write sides use corresponding WRITE_ONCE() to avoid store-tearing. Note that tcp_inq_hint() was already using READ_ONCE(tp->rcv_nxt) syzbot reported : BUG: KCSAN: data-race in tcp_poll / tcp_queue_rcv write to 0xffff888120425770 of 4 bytes by interrupt on cpu 0: tcp_rcv_nxt_update net/ipv4/tcp_input.c:3365 [inline] tcp_queue_rcv+0x180/0x380 net/ipv4/tcp_input.c:4638 tcp_rcv_established+0xbf1/0xf50 net/ipv4/tcp_input.c:5616 tcp_v4_do_rcv+0x381/0x4e0 net/ipv4/tcp_ipv4.c:1542 tcp_v4_rcv+0x1a03/0x1bf0 net/ipv4/tcp_ipv4.c:1923 ip_protocol_deliver_rcu+0x51/0x470 net/ipv4/ip_input.c:204 ip_local_deliver_finish+0x110/0x140 net/ipv4/ip_input.c:231 NF_HOOK include/linux/netfilter.h:305 [inline] NF_HOOK include/linux/netfilter.h:299 [inline] ip_local_deliver+0x133/0x210 net/ipv4/ip_input.c:252 dst_input include/net/dst.h:442 [inline] ip_rcv_finish+0x121/0x160 net/ipv4/ip_input.c:413 NF_HOOK include/linux/netfilter.h:305 [inline] NF_HOOK include/linux/netfilter.h:299 [inline] ip_rcv+0x18f/0x1a0 net/ipv4/ip_input.c:523 __netif_receive_skb_one_core+0xa7/0xe0 net/core/dev.c:5004 __netif_receive_skb+0x37/0xf0 net/core/dev.c:5118 netif_receive_skb_internal+0x59/0x190 net/core/dev.c:5208 napi_skb_finish net/core/dev.c:5671 [inline] napi_gro_receive+0x28f/0x330 net/core/dev.c:5704 receive_buf+0x284/0x30b0 drivers/net/virtio_net.c:1061 read to 0xffff888120425770 of 4 bytes by task 7254 on cpu 1: tcp_stream_is_readable net/ipv4/tcp.c:480 [inline] tcp_poll+0x204/0x6b0 net/ipv4/tcp.c:554 sock_poll+0xed/0x250 net/socket.c:1256 vfs_poll include/linux/poll.h:90 [inline] ep_item_poll.isra.0+0x90/0x190 fs/eventpoll.c:892 ep_send_events_proc+0x113/0x5c0 fs/eventpoll.c:1749 ep_scan_ready_list.constprop.0+0x189/0x500 fs/eventpoll.c:704 ep_send_events fs/eventpoll.c:1793 [inline] ep_poll+0xe3/0x900 fs/eventpoll.c:1930 do_epoll_wait+0x162/0x180 fs/eventpoll.c:2294 __do_sys_epoll_pwait fs/eventpoll.c:2325 [inline] __se_sys_epoll_pwait fs/eventpoll.c:2311 [inline] __x64_sys_epoll_pwait+0xcd/0x170 fs/eventpoll.c:2311 do_syscall_64+0xcf/0x2f0 arch/x86/entry/common.c:296 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 7254 Comm: syz-fuzzer Not tainted 5.3.0+ #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-13tcp: add rcu protection around tp->fastopen_rskEric Dumazet10-21/+32
Both tcp_v4_err() and tcp_v6_err() do the following operations while they do not own the socket lock : fastopen = tp->fastopen_rsk; snd_una = fastopen ? tcp_rsk(fastopen)->snt_isn : tp->snd_una; The problem is that without appropriate barrier, the compiler might reload tp->fastopen_rsk and trigger a NULL deref. request sockets are protected by RCU, we can simply add the missing annotations and barriers to solve the issue. Fixes: 168a8f58059a ("tcp: TCP Fast Open Server - main code path") Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-12Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpfDavid S. Miller1-15/+27
Alexei Starovoitov says: ==================== pull-request: bpf 2019-10-12 The following pull-request contains BPF updates for your *net* tree. The main changes are: 1) a bunch of small fixes. Nothing critical. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-11rxrpc: Fix possible NULL pointer access in ICMP handlingDavid Howells1-0/+3
If an ICMP packet comes in on the UDP socket backing an AF_RXRPC socket as the UDP socket is being shut down, rxrpc_error_report() may get called to deal with it after sk_user_data on the UDP socket has been cleared, leading to a NULL pointer access when this local endpoint record gets accessed. Fix this by just returning immediately if sk_user_data was NULL. The oops looks like the following: #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page ... RIP: 0010:rxrpc_error_report+0x1bd/0x6a9 ... Call Trace: ? sock_queue_err_skb+0xbd/0xde ? __udp4_lib_err+0x313/0x34d __udp4_lib_err+0x313/0x34d icmp_unreach+0x1ee/0x207 icmp_rcv+0x25b/0x28f ip_protocol_deliver_rcu+0x95/0x10e ip_local_deliver+0xe9/0x148 __netif_receive_skb_one_core+0x52/0x6e process_backlog+0xdc/0x177 net_rx_action+0xf9/0x270 __do_softirq+0x1b6/0x39a ? smpboot_register_percpu_thread+0xce/0xce run_ksoftirqd+0x1d/0x42 smpboot_thread_fn+0x19e/0x1b3 kthread+0xf1/0xf6 ? kthread_delayed_work_timer_fn+0x83/0x83 ret_from_fork+0x24/0x30 Fixes: 17926a79320a ("[AF_RXRPC]: Provide secure RxRPC sockets for use by userspace and kernel both") Reported-by: syzbot+611164843bd48cc2190c@syzkaller.appspotmail.com Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-11devlink: propagate extack down to health reporter opsJiri Pirko1-9/+11
During health reporter operations, driver might want to fill-up the extack message, so propagate extack down to the health reporter ops. Signed-off-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-11devlink: don't do reporter recovery if the state is healthyJiri Pirko1-0/+3
If reporter state is healthy, don't call into a driver for recover and don't increase recovery count. Signed-off-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-11sock_get_timeout: drop unnecessary return variableVito Caputo1-6/+3
Remove pointless use of size return variable by directly returning sizes. Signed-off-by: Vito Caputo <vcaputo@pengaru.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-11af_unix: __unix_find_socket_byname() cleanupVito Caputo1-4/+2
Remove pointless return variable dance. Appears vestigial from when the function did locking as seen in unix_find_socket_byinode(), but locking is handled in unix_find_socket_byname() for __unix_find_socket_byname(). Signed-off-by: Vito Caputo <vcaputo@pengaru.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-11Merge tag 'nfs-for-5.4-2' of git://git.linux-nfs.org/projects/anna/linux-nfsLinus Torvalds1-9/+8
Pull NFS client bugfixes from Anna Schumaker: "Stable bugfixes: - Fix O_DIRECT accounting of number of bytes read/written # v4.1+ Other fixes: - Fix nfsi->nrequests count error on nfs_inode_remove_request() - Remove redundant mirror tracking in O_DIRECT - Fix leak of clp->cl_acceptor string - Fix race to sk_err after xs_error_report" * tag 'nfs-for-5.4-2' of git://git.linux-nfs.org/projects/anna/linux-nfs: SUNRPC: fix race to sk_err after xs_error_report NFSv4: Fix leak of clp->cl_acceptor string NFS: Remove redundant mirror tracking in O_DIRECT NFS: Fix O_DIRECT accounting of number of bytes read/written nfs: Fix nfsi->nrequests count error on nfs_inode_remove_request
2019-10-11xdp: Trivial, fix spelling in function descriptionAnton Ivanov1-1/+1
Fix typo 'boolian' into 'boolean'. Signed-off-by: Anton Ivanov <anton.ivanov@cambridgegreys.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20191011084303.28418-1-anton.ivanov@cambridgegreys.com
2019-10-11flow_dissector: Allow updating the flow dissector program atomicallyJakub Sitnicki1-3/+7
It is currently not possible to detach the flow dissector program and attach a new one in an atomic fashion, that is with a single syscall. Attempts to do so will be met with EEXIST error. This makes updates to flow dissector program hard. Traffic steering that relies on BPF-powered flow dissection gets disrupted while old program has been already detached but the new one has not been attached yet. There is also a window of opportunity to attach a flow dissector to a non-root namespace while updating the root flow dissector, thus blocking the update. Lastly, the behavior is inconsistent with cgroup BPF programs, which can be replaced with a single bpf(BPF_PROG_ATTACH, ...) syscall without any restrictions. Allow attaching a new flow dissector program when another one is already present with a restriction that it can't be the same program. Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Stanislav Fomichev <sdf@google.com> Acked-by: Martin KaFai Lau <kafai@fb.com> Link: https://lore.kernel.org/bpf/20191011082946.22695-2-jakub@cloudflare.com
2019-10-11net: sctp: Rename fallthrough label to unhandledJoe Perches1-6/+6
fallthrough will become a pseudo reserved keyword so this only use of fallthrough is better renamed to allow it. Signed-off-by: Joe Perches <joe@perches.com> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Reviewed-by: Kees Cook <keescook@chromium.org> Acked-by: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-10-11mac80211: minstrel_ht: rename prob_ewma to prob_avg, use it for the new averageFelix Fietkau6-68/+63
Reduces per-rate data structure size Signed-off-by: Felix Fietkau <nbd@nbd.name> Link: https://lore.kernel.org/r/20191008171139.96476-3-nbd@nbd.name Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2019-10-11mac80211: minstrel_ht: replace rate stats ewma with a better moving averageFelix Fietkau3-8/+76
Rate success probability usually fluctuates a lot under normal conditions. With a simple EWMA, noise and fluctuation can be reduced by increasing the window length, but that comes at the cost of introducing lag on sudden changes. This change replaces the EWMA implementation with a moving average that's designed to significantly reduce lag while keeping a bigger window size by being better at filtering out noise. It is only slightly more expensive than the simple EWMA and still avoids divisions in its calculation. The algorithm is adapted from an implementation intended for a completely different field (stock market trading), where the tradeoff of lag vs noise filtering is equally important. It is based on the "smoothing filter" from http://www.stockspotter.com/files/PredictiveIndicators.pdf. I have adapted it to fixed-point math with some constants so that it uses only addition, bit shifts and multiplication To better make use of the filtering and bigger window size, the update interval time is cut in half. For testing, the algorithm can be reverted to the older one via debugfs Signed-off-by: Felix Fietkau <nbd@nbd.name> Link: https://lore.kernel.org/r/20191008171139.96476-2-nbd@nbd.name Signed-off-by: Johannes Berg <johannes.berg@intel.com>