syzbot

netlink: 'syz-executor.2': attribute type 10 has an invalid length.
netlink: 'syz-executor.2': attribute type 10 has an invalid length.
netlink: 16 bytes leftover after parsing attributes in process `syz-executor.2'.
rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	0-...!: (10500 ticks this GP) idle=ef2/1/0x4000000000000002 softirq=166465/166465 fqs=0 
rcu: 	 (t=10500 jiffies g=215041 q=4128)
rcu: rcu_preempt kthread starved for 10500 jiffies! g215041 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=0
rcu: RCU grace-period kthread stack dump:
rcu_preempt     I29008    10      2 0x80000000
Call Trace:
 context_switch kernel/sched/core.c:2826 [inline]
 __schedule+0x866/0x1dc0 kernel/sched/core.c:3474
 schedule+0x92/0x1c0 kernel/sched/core.c:3518
 schedule_timeout+0x4db/0xfc0 kernel/time/timer.c:1804
 rcu_gp_kthread+0xd5c/0x2190 kernel/rcu/tree.c:2202
 kthread+0x354/0x420 kernel/kthread.c:246
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415
NMI backtrace for cpu 0
CPU: 0 PID: 7650 Comm: syz-executor.1 Not tainted 4.19.71 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x172/0x1f0 lib/dump_stack.c:113
 nmi_cpu_backtrace.cold+0x63/0xa4 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x1b0/0x1f8 lib/nmi_backtrace.c:62
 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38
 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline]
 rcu_dump_cpu_stacks+0x189/0x1d5 kernel/rcu/tree.c:1340
 print_cpu_stall kernel/rcu/tree.c:1478 [inline]
 check_cpu_stall kernel/rcu/tree.c:1550 [inline]
 __rcu_pending kernel/rcu/tree.c:3293 [inline]
 rcu_pending kernel/rcu/tree.c:3336 [inline]
 rcu_check_callbacks.cold+0x5e3/0xd90 kernel/rcu/tree.c:2682
 update_process_times+0x32/0x80 kernel/time/timer.c:1636
 tick_sched_handle+0xa2/0x190 kernel/time/tick-sched.c:164
 tick_sched_timer+0x47/0x130 kernel/time/tick-sched.c:1274
 __run_hrtimer kernel/time/hrtimer.c:1398 [inline]
 __hrtimer_run_queues+0x33b/0xdc0 kernel/time/hrtimer.c:1460
 hrtimer_interrupt+0x314/0x770 kernel/time/hrtimer.c:1518
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1067 [inline]
 smp_apic_timer_interrupt+0x111/0x550 arch/x86/kernel/apic/apic.c:1092
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:893
 </IRQ>
RIP: 0010:hhf_dequeue+0x5a1/0xa00 net/sched/sch_hhf.c:437
Code: e8 03 42 0f b6 14 20 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 32 04 00 00 45 0f af b5 d4 02 00 00 48 89 df 45 01 fe <44> 89 73 10 e8 76 48 97 fd 31 ff 41 89 c6 89 c6 e8 4a de dc fb 45
RSP: 0018:ffff8880556359e8 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13
RAX: 0000000000000007 RBX: ffff88808cba74f8 RCX: ffffc900086ab000
RDX: 0000000000000000 RSI: ffffffff858e893b RDI: ffff88808cba74f8
RBP: ffff888055635a38 R08: ffff88804fed44c0 R09: 0000000000000009
R10: ffff88804fed4ea8 R11: 00000000cc2dbdf9 R12: dffffc0000000000
R13: ffff88808cba7240 R14: 0000000000000000 R15: 0000000000000000
 dequeue_skb net/sched/sch_generic.c:277 [inline]
 qdisc_restart net/sched/sch_generic.c:380 [inline]
 __qdisc_run+0x1e7/0x1960 net/sched/sch_generic.c:398
 __dev_xmit_skb net/core/dev.c:3501 [inline]
 __dev_queue_xmit+0x165c/0x2fe0 net/core/dev.c:3811
 dev_queue_xmit+0x18/0x20 net/core/dev.c:3876
 br_dev_queue_push_xmit+0x405/0x5d0 net/bridge/br_forward.c:56
 NF_HOOK include/linux/netfilter.h:289 [inline]
 NF_HOOK include/linux/netfilter.h:283 [inline]
 br_forward_finish+0xfa/0x400 net/bridge/br_forward.c:69
 NF_HOOK include/linux/netfilter.h:289 [inline]
 NF_HOOK include/linux/netfilter.h:283 [inline]
 __br_forward+0x647/0xb30 net/bridge/br_forward.c:113
 br_flood+0x613/0x710 net/bridge/br_forward.c:240
 br_dev_xmit+0xeeb/0x1490 net/bridge/br_device.c:103
 __netdev_start_xmit include/linux/netdevice.h:4303 [inline]
 netdev_start_xmit include/linux/netdevice.h:4312 [inline]
 xmit_one net/core/dev.c:3257 [inline]
 dev_hard_start_xmit+0x1a5/0x980 net/core/dev.c:3273
 __dev_queue_xmit+0x2704/0x2fe0 net/core/dev.c:3843
 dev_queue_xmit+0x18/0x20 net/core/dev.c:3876
 neigh_resolve_output net/core/neighbour.c:1369 [inline]
 neigh_resolve_output+0x5b7/0x980 net/core/neighbour.c:1349
 neigh_output include/net/neighbour.h:501 [inline]
 ip6_finish_output2+0xb7f/0x2550 net/ipv6/ip6_output.c:120
 ip6_finish_output+0x574/0xbe0 net/ipv6/ip6_output.c:154
 NF_HOOK_COND include/linux/netfilter.h:278 [inline]
 ip6_output+0x235/0x7c0 net/ipv6/ip6_output.c:171
 dst_output include/net/dst.h:447 [inline]
 NF_HOOK include/linux/netfilter.h:289 [inline]
 ndisc_send_skb+0xf3b/0x1460 net/ipv6/ndisc.c:491
 ndisc_send_ns+0x3a9/0x850 net/ipv6/ndisc.c:633
 ndisc_solicit+0x2ed/0x470 net/ipv6/ndisc.c:725
 neigh_probe+0xc6/0x110 net/core/neighbour.c:911
 __neigh_event_send+0x3ee/0x1140 net/core/neighbour.c:1069
 neigh_event_send include/net/neighbour.h:436 [inline]
 neigh_resolve_output+0x5e1/0x980 net/core/neighbour.c:1353
 neigh_output include/net/neighbour.h:501 [inline]
 ip6_finish_output2+0xb7f/0x2550 net/ipv6/ip6_output.c:120
 ip6_fragment+0x146d/0x3770 net/ipv6/ip6_output.c:846
 ip6_finish_output+0x6a7/0xbe0 net/ipv6/ip6_output.c:152
 NF_HOOK_COND include/linux/netfilter.h:278 [inline]
 ip6_output+0x235/0x7c0 net/ipv6/ip6_output.c:171
 dst_output include/net/dst.h:447 [inline]
 NF_HOOK include/linux/netfilter.h:289 [inline]
 NF_HOOK include/linux/netfilter.h:283 [inline]
 ip6_xmit+0xe44/0x2030 net/ipv6/ip6_output.c:275
 sctp_v6_xmit+0x340/0x690 net/sctp/ipv6.c:229
 sctp_packet_transmit+0x1b17/0x3630 net/sctp/output.c:659
 sctp_packet_singleton net/sctp/outqueue.c:791 [inline]
 sctp_outq_flush_ctrl.constprop.0+0x73c/0xd30 net/sctp/outqueue.c:922
 sctp_outq_flush+0xe8/0x27a0 net/sctp/outqueue.c:1204
 sctp_outq_uncork+0x6c/0x80 net/sctp/outqueue.c:776
 sctp_cmd_interpreter net/sctp/sm_sideeffect.c:1796 [inline]
 sctp_side_effects net/sctp/sm_sideeffect.c:1199 [inline]
 sctp_do_sm+0x50d/0x5190 net/sctp/sm_sideeffect.c:1170
 sctp_primitive_ASSOCIATE+0x9d/0xd0 net/sctp/primitive.c:88
 sctp_sendmsg_to_asoc+0xc0a/0x1de0 net/sctp/socket.c:1942
 sctp_sendmsg+0x109a/0x17d0 net/sctp/socket.c:2132
 inet_sendmsg+0x141/0x5d0 net/ipv4/af_inet.c:798
 sock_sendmsg_nosec net/socket.c:622 [inline]
 sock_sendmsg+0xd7/0x130 net/socket.c:632
 ___sys_sendmsg+0x803/0x920 net/socket.c:2115
 __sys_sendmsg+0x105/0x1d0 net/socket.c:2153
 __do_sys_sendmsg net/socket.c:2162 [inline]
 __se_sys_sendmsg net/socket.c:2160 [inline]
 __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2160
 do_syscall_64+0xfd/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x4598e9
Code: fd b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 cb b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f15fdfb4c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00000000004598e9
RDX: 0000000000000045 RSI: 0000000020002700 RDI: 0000000000000004
RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f15fdfb56d4
R13: 00000000004c711b R14: 00000000004dc828 R15: 00000000ffffffff