INFO: task syz.1.1473:10379 blocked for more than 143 seconds. Not tainted 6.13.0-syzkaller-09760-g69e858e0b8b2 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.1473 state:D stack:28048 pid:10379 tgid:10377 ppid:5815 task_flags:0x400040 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5377 [inline] __schedule+0xf43/0x5890 kernel/sched/core.c:6764 __schedule_loop kernel/sched/core.c:6841 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6856 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6913 __mutex_lock_common kernel/locking/mutex.c:662 [inline] __mutex_lock+0x6bd/0xb10 kernel/locking/mutex.c:730 rtnl_lock net/core/rtnetlink.c:79 [inline] rtnetlink_rcv_msg+0x372/0xea0 net/core/rtnetlink.c:6917 netlink_rcv_skb+0x16b/0x440 net/netlink/af_netlink.c:2543 netlink_unicast_kernel net/netlink/af_netlink.c:1322 [inline] netlink_unicast+0x53c/0x7f0 net/netlink/af_netlink.c:1348 netlink_sendmsg+0x8b8/0xd70 net/netlink/af_netlink.c:1892 sock_sendmsg_nosec net/socket.c:713 [inline] __sock_sendmsg net/socket.c:728 [inline] ____sys_sendmsg+0xaaf/0xc90 net/socket.c:2568 ___sys_sendmsg+0x135/0x1e0 net/socket.c:2622 __sys_sendmsg+0x16e/0x220 net/socket.c:2654 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fc9c198cda9 RSP: 002b:00007fc9c288a038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007fc9c1ba6080 RCX: 00007fc9c198cda9 RDX: 0000000000000000 RSI: 0000000020000140 RDI: 0000000000000005 RBP: 00007fc9c1a0e2a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fc9c1ba6080 R15: 00007ffc06c02278 Showing all locks held in the system: 3 locks held by kworker/u8:1/12: #0: ffff88814d977948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x1293/0x1ba0 kernel/workqueue.c:3211 #1: ffffc90000117d18 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_one_work+0x921/0x1ba0 kernel/workqueue.c:3212 #2: ffffffff8fef36e8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:129 [inline] #2: ffffffff8fef36e8 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_verify_work+0x12/0x30 net/ipv6/addrconf.c:4730 2 locks held by kworker/1:0/25: 1 lock held by khungtaskd/30: #0: ffffffff8e1bcbc0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8e1bcbc0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8e1bcbc0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x7f/0x390 kernel/locking/lockdep.c:6746 6 locks held by kworker/u8:3/52: 3 locks held by kworker/u8:4/72: 1 lock held by kswapd0/84: 3 locks held by kworker/0:2/970: 3 locks held by kworker/u8:6/1461: 3 locks held by kworker/u8:7/4384: 3 locks held by syslogd/5175: 2 locks held by dhcpcd/5486: 2 locks held by getty/5576: #0: ffff8880315ce0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc90002fde2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0xfba/0x1480 drivers/tty/n_tty.c:2211 2 locks held by syz-executor/5811: 2 locks held by kworker/1:4/5871: 3 locks held by kworker/1:5/5902: #0: ffff88801b078d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x1293/0x1ba0 kernel/workqueue.c:3211 #1: ffffc900045bfd18 (deferred_process_work){+.+.}-{0:0}, at: process_one_work+0x921/0x1ba0 kernel/workqueue.c:3212 #2: ffffffff8fef36e8 (rtnl_mutex){+.+.}-{4:4}, at: switchdev_deferred_process_work+0xe/0x20 net/switchdev/switchdev.c:104 2 locks held by kworker/u8:10/6081: 1 lock held by syz.0.273/6914: #0: ffffffff8fef36e8 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:702 [inline] #0: ffffffff8fef36e8 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x38/0x230 drivers/net/tun.c:3521 2 locks held by syz.4.1462/10351: 1 lock held by syz.1.1473/10379: #0: ffffffff8fef36e8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fef36e8 (rtnl_mutex){+.+.}-{4:4}, at: rtnetlink_rcv_msg+0x372/0xea0 net/core/rtnetlink.c:6917 2 locks held by kworker/0:4/10432: 2 locks held by syz-executor/10435: ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.13.0-syzkaller-09760-g69e858e0b8b2 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x29c/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:236 [inline] watchdog+0xf62/0x12b0 kernel/hung_task.c:399 kthread+0x3af/0x750 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 52 Comm: kworker/u8:3 Not tainted 6.13.0-syzkaller-09760-g69e858e0b8b2 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 Workqueue: events_unbound nsim_dev_trap_report_work RIP: 0010:check_kcov_mode kernel/kcov.c:183 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x13/0x70 kernel/kcov.c:217 Code: 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 65 48 8b 15 54 2a 4a 7e 65 8b 05 55 2a 4a 7e 00 01 ff 00 48 8b 34 24 74 1d f6 c4 01 74 43 a9 00 00 0f 00 75 RSP: 0018:ffffc90000007760 EFLAGS: 00000282 RAX: 0000000080000102 RBX: ffff88802f660000 RCX: 1ffffffff2de37d0 RDX: ffff88801f2f4880 RSI: ffffffff8b6ceca0 RDI: ffffffff8bd33d60 RBP: ffff888027f87140 R08: 0000000000000001 R09: fffffbfff2dd71b7 R10: ffffffff96eb8dbf R11: 0000000000000005 R12: ffff888027f87140 R13: 1ffff92000000ef1 R14: 0000000000000080 R15: ffffc900000077e8 FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffe9a4957f8 CR3: 000000006f47c000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: ip6_pol_route+0x409/0x1120 net/ipv6/route.c:2272 pol_lookup_func include/net/ip6_fib.h:616 [inline] fib6_rule_lookup+0x536/0x720 net/ipv6/fib6_rules.c:119 ip6_route_input_lookup net/ipv6/route.c:2300 [inline] ip6_route_input+0x663/0xc10 net/ipv6/route.c:2596 ip6_rcv_finish_core.constprop.0+0x1a0/0x5d0 net/ipv6/ip6_input.c:66 ip6_rcv_finish net/ipv6/ip6_input.c:77 [inline] NF_HOOK include/linux/netfilter.h:314 [inline] NF_HOOK include/linux/netfilter.h:308 [inline] ipv6_rcv+0x1e4/0x680 net/ipv6/ip6_input.c:309 __netif_receive_skb_one_core+0x12e/0x1e0 net/core/dev.c:5828 __netif_receive_skb+0x1d/0x160 net/core/dev.c:5941 process_backlog+0x443/0x15f0 net/core/dev.c:6289 __napi_poll.constprop.0+0xb7/0x550 net/core/dev.c:7106 napi_poll net/core/dev.c:7175 [inline] net_rx_action+0xa94/0x1010 net/core/dev.c:7297 handle_softirqs+0x213/0x8f0 kernel/softirq.c:561 do_softirq kernel/softirq.c:462 [inline] do_softirq+0xb2/0xf0 kernel/softirq.c:449 __local_bh_enable_ip+0x100/0x120 kernel/softirq.c:389 spin_unlock_bh include/linux/spinlock.h:396 [inline] nsim_dev_trap_report drivers/net/netdevsim/dev.c:820 [inline] nsim_dev_trap_report_work+0x8c7/0xd00 drivers/net/netdevsim/dev.c:851 process_one_work+0x9c5/0x1ba0 kernel/workqueue.c:3236 process_scheduled_works kernel/workqueue.c:3317 [inline] worker_thread+0x6c8/0xf00 kernel/workqueue.c:3398 kthread+0x3af/0x750 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244