INFO: task syz.1.27:5953 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.27 state:D stack:27872 pid: 5953 ppid: 5721 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5049 [inline] __schedule+0x11bb/0x4390 kernel/sched/core.c:6395 schedule+0x11b/0x1e0 kernel/sched/core.c:6478 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6537 rwsem_down_read_slowpath+0x528/0x990 kernel/locking/rwsem.c:1055 __down_read_common kernel/locking/rwsem.c:1239 [inline] __down_read kernel/locking/rwsem.c:1252 [inline] down_read+0x96/0x2e0 kernel/locking/rwsem.c:1500 user_get_super+0x118/0x240 fs/super.c:850 quotactl_block fs/quota/quota.c:889 [inline] __do_sys_quotactl fs/quota/quota.c:953 [inline] __se_sys_quotactl+0x45e/0x6c0 fs/quota/quota.c:915 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f0fb3f82b69 RSP: 002b:00007f0fb31b0038 EFLAGS: 00000246 ORIG_RAX: 00000000000000b3 RAX: ffffffffffffffda RBX: 00007f0fb41aa160 RCX: 00007f0fb3f82b69 RDX: 0000000000000000 RSI: 0000200000000900 RDI: ffffffff80000600 RBP: 00007f0fb4005df1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f0fb41aa160 R15: 00007ffdda3a6088 INFO: task syz.2.28:5971 blocked for more than 145 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.28 state:D stack:27872 pid: 5971 ppid: 5850 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5049 [inline] __schedule+0x11bb/0x4390 kernel/sched/core.c:6395 schedule+0x11b/0x1e0 kernel/sched/core.c:6478 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6537 rwsem_down_read_slowpath+0x528/0x990 kernel/locking/rwsem.c:1055 __down_read_common kernel/locking/rwsem.c:1239 [inline] __down_read kernel/locking/rwsem.c:1252 [inline] down_read+0x96/0x2e0 kernel/locking/rwsem.c:1500 user_get_super+0x118/0x240 fs/super.c:850 quotactl_block fs/quota/quota.c:889 [inline] __do_sys_quotactl fs/quota/quota.c:953 [inline] __se_sys_quotactl+0x45e/0x6c0 fs/quota/quota.c:915 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f4ca8639b69 RSP: 002b:00007f4ca7888038 EFLAGS: 00000246 ORIG_RAX: 00000000000000b3 RAX: ffffffffffffffda RBX: 00007f4ca8861080 RCX: 00007f4ca8639b69 RDX: 0000000000000000 RSI: 0000200000000900 RDI: ffffffff80000600 RBP: 00007f4ca86bcdf1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f4ca8861080 R15: 00007ffe929308d8 Showing all locks held in the system: 1 lock held by khungtaskd/27: #0: ffffffff8c11c760 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 3 locks held by kworker/u4:3/155: #0: ffff888016879138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1 #1: ffffc90002057d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285 #2: ffffffff8d238988 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xa/0x50 net/core/link_watch.c:251 2 locks held by getty/3950: #0: ffff88802b8bf098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252 #1: ffffc900025e62e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x5ba/0x1a30 drivers/tty/n_tty.c:2158 3 locks held by kworker/0:19/4293: #0: ffff88802a8f3538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1 #1: ffffc9000366fd00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285 #2: ffffffff8d238988 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xc4/0x1520 net/ipv6/addrconf.c:4110 3 locks held by kworker/1:5/4296: #0: ffff88802a8f3538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1 #1: ffffc900035efd00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285 #2: ffff88804edbb240 (&data->fib_lock){+.+.}-{3:3}, at: nsim_fib_event_work+0x271/0x3240 drivers/net/netdevsim/fib.c:1480 1 lock held by syz.1.18/5105: 1 lock held by syz.2.19/5184: 3 locks held by kworker/u4:7/5199: 1 lock held by syz.0.17/5293: 1 lock held by syz.4.21/5304: 1 lock held by syz.3.20/5310: 1 lock held by syz.5.22/5516: 1 lock held by syz.6.23/5665: 1 lock held by syz.7.24/5806: 1 lock held by syz.8.25/5845: 1 lock held by syz.9.26/5864: 1 lock held by syz.1.27/5953: #0: ffff88805cba60e0 (&type->s_umount_key#54){.+.+}-{3:3}, at: user_get_super+0x118/0x240 fs/super.c:850 1 lock held by syz.2.28/5971: #0: ffff88807aeb60e0 (&type->s_umount_key#54){.+.+}-{3:3}, at: user_get_super+0x118/0x240 fs/super.c:850 1 lock held by syz.0.29/6022: #0: ffff88807ba240e0 (&type->s_umount_key#54){.+.+}-{3:3}, at: user_get_super+0x118/0x240 fs/super.c:850 1 lock held by syz.3.30/6031: #0: ffff88801f1960e0 (&type->s_umount_key#54){.+.+}-{3:3}, at: user_get_super+0x118/0x240 fs/super.c:850 1 lock held by syz.4.31/6045: #0: ffff8880744820e0 (&type->s_umount_key#54){.+.+}-{3:3}, at: user_get_super+0x118/0x240 fs/super.c:850 1 lock held by syz.5.32/6092: #0: ffff88805aab80e0 (&type->s_umount_key#54){.+.+}-{3:3}, at: user_get_super+0x118/0x240 fs/super.c:850 1 lock held by syz.6.33/6111: #0: ffff88802b9400e0 (&type->s_umount_key#54){.+.+}-{3:3}, at: user_get_super+0x118/0x240 fs/super.c:850 1 lock held by syz.7.34/6160: #0: ffff88805a0920e0 (&type->s_umount_key#54){.+.+}-{3:3}, at: user_get_super+0x118/0x240 fs/super.c:850 1 lock held by syz.8.35/6199: #0: ffff888073e0c0e0 (&type->s_umount_key#54){.+.+}-{3:3}, at: user_get_super+0x118/0x240 fs/super.c:850 1 lock held by syz.9.36/6202: #0: ffff88805382e0e0 (&type->s_umount_key#54){.+.+}-{3:3}, at: user_get_super+0x118/0x240 fs/super.c:850 1 lock held by syz-executor/6226: #0: ffffffff8d238988 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline] #0: ffffffff8d238988 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x7a5/0xe90 net/core/rtnetlink.c:5681 3 locks held by syz-executor/6227: #0: ffffffff8d238988 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline] #0: ffffffff8d238988 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x7a5/0xe90 net/core/rtnetlink.c:5681 #1: ffff8880566a93e8 (&wg->device_update_lock){+.+.}-{3:3}, at: wg_open+0x223/0x420 drivers/net/wireguard/device.c:49 #2: ffffffff8c1211e8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:290 [inline] #2: ffffffff8c1211e8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x347/0x6b0 kernel/rcu/tree_exp.h:845 1 lock held by syz.1.37/6234: #0: ffff88805cba60e0 (&type->s_umount_key#54){.+.+}-{3:3}, at: user_get_super+0x118/0x240 fs/super.c:850 1 lock held by syz.2.38/6253: #0: ffff88807aeb60e0 (&type->s_umount_key#54){.+.+}-{3:3}, at: user_get_super+0x118/0x240 fs/super.c:850 1 lock held by syz-executor/6259: #0: ffffffff8d238988 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline] #0: ffffffff8d238988 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x7a5/0xe90 net/core/rtnetlink.c:5681 1 lock held by syz.0.39/6270: #0: ffff88807ba240e0 (&type->s_umount_key#54){.+.+}-{3:3}, at: user_get_super+0x118/0x240 fs/super.c:850 1 lock held by syz-executor/6279: #0: ffffffff8d238988 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline] #0: ffffffff8d238988 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x7a5/0xe90 net/core/rtnetlink.c:5681 2 locks held by syz-executor/6314: #0: ffffffff8d22cd10 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x32e/0x5b0 net/core/net_namespace.c:499 #1: ffffffff8d238988 (rtnl_mutex){+.+.}-{3:3}, at: ip_tunnel_init_net+0x224/0x6b0 net/ipv4/ip_tunnel.c:1083 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 27 Comm: khungtaskd Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 Call Trace: dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106 nmi_cpu_backtrace+0x397/0x3d0 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:212 [inline] watchdog+0xe0f/0xe50 kernel/hung_task.c:369 kthread+0x436/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 5015 Comm: kworker/u4:6 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 Workqueue: bat_events batadv_nc_worker RIP: 0010:get_current arch/x86/include/asm/current.h:15 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x4/0x60 kernel/kcov.c:205 Code: 84 00 00 00 00 00 53 48 89 fb e8 17 00 00 00 48 8b 3d 50 d3 f1 0b 48 89 de 5b e9 57 9e 43 00 00 00 cc cc 00 00 cc 48 8b 04 24 <65> 48 8b 0d a4 a3 8a 7e 65 8b 15 a5 a3 8a 7e 81 e2 00 01 ff 00 74 RSP: 0018:ffffc9000315fb68 EFLAGS: 00000287 RAX: ffffffff897f17e5 RBX: ffffffff897f1370 RCX: ffff88807d6a3b80 RDX: 0000000000000000 RSI: ffffffff8a59e560 RDI: ffff88807d6a3b80 RBP: 0000000000000001 R08: dffffc0000000000 R09: fffffbfff1ff7c19 R10: fffffbfff1ff7c19 R11: 1ffffffff1ff7c18 R12: ffff88801a9e1410 R13: 000000000000003f R14: ffff88801a9e1400 R15: ffff88802294cc80 FS: 0000000000000000(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000056191c86e088 CR3: 0000000055a52000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rcu_lock_release+0x5/0x20 include/linux/rcupdate.h:317 rcu_read_unlock include/linux/rcupdate.h:773 [inline] batadv_nc_process_nc_paths+0x2c0/0x350 net/batman-adv/network-coding.c:703 batadv_nc_worker+0x4e4/0x5c0 net/batman-adv/network-coding.c:739 process_one_work+0x863/0x1000 kernel/workqueue.c:2310 worker_thread+0xaa8/0x12a0 kernel/workqueue.c:2457 kthread+0x436/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287