INFO: task syz-executor:4185 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:21896 pid: 4185 ppid: 1 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 io_schedule+0x7c/0xd0 kernel/sched/core.c:8503 wait_on_page_bit_common+0x815/0xe00 mm/filemap.c:1356 lock_page include/linux/pagemap.h:625 [inline] truncate_inode_pages_range+0x97f/0xef0 mm/truncate.c:394 evict+0x498/0x870 fs/inode.c:649 dispose_list fs/inode.c:680 [inline] evict_inodes+0x604/0x690 fs/inode.c:734 generic_shutdown_super+0x93/0x300 fs/super.c:454 kill_block_super+0x7c/0xe0 fs/super.c:1427 deactivate_locked_super+0x93/0xf0 fs/super.c:335 cleanup_mnt+0x418/0x4d0 fs/namespace.c:1148 task_work_run+0x125/0x1a0 kernel/task_work.c:188 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop+0x10f/0x130 kernel/entry/common.c:181 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline] syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f45c7a9aa77 RSP: 002b:00007ffd98626738 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007f45c7a9aa77 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffd986267f0 RBP: 00007ffd986267f0 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffd98627880 R13: 00007f45c7b1dd7d R14: 0000000000023ecc R15: 00007ffd986278c0 INFO: task syz.0.486:6314 blocked for more than 144 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.486 state:D stack:25856 pid: 6314 ppid: 4181 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 iterate_supers+0xa4/0x1d0 fs/super.c:716 ksys_sync+0x91/0x150 fs/sync.c:102 __ia32_sys_sync+0xa/0x10 fs/sync.c:113 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: 0033:0x7f68cc3f0749 RSP: 002b:00007f68ca657038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2 RAX: ffffffffffffffda RBX: 00007f68cc646fa0 RCX: 00007f68cc3f0749 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007f68cc646fa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f68cc647038 R14: 00007f68cc646fa0 R15: 00007ffc87b32c28 Showing all locks held in the system: 2 locks held by ksoftirqd/1/20: 1 lock held by khungtaskd/27: #0: ffffffff8c11c760 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 1 lock held by udevd/3560: #0: ffff8880206a0518 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x157/0xa60 block/bdev.c:820 2 locks held by getty/3951: #0: ffff88814c627098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252 #1: ffffc90002cf62e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x5ba/0x1a30 drivers/tty/n_tty.c:2158 1 lock held by syz-executor/4185: #0: ffff8880735800e0 (&type->s_umount_key#60){++++}-{3:3}, at: deactivate_super+0xa0/0xd0 fs/super.c:365 4 locks held by kworker/u4:6/4340: #0: ffff8880169cd938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1 #1: ffffc9000443fd00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285 #2: ffffffff8d22cd10 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x132/0xb80 net/core/net_namespace.c:589 #3: ffffffff8c1211e8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:290 [inline] #3: ffffffff8c1211e8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x347/0x6b0 kernel/rcu/tree_exp.h:845 2 locks held by kworker/1:16/4993: #0: ffff888016872138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1 #1: ffffc900037ffd00 ((work_completion)(&rew.rew_work)){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285 1 lock held by udevd/5476: #0: ffff8880206a0518 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x157/0xa60 block/bdev.c:820 1 lock held by syz.0.486/6314: #0: ffff8880735800e0 (&type->s_umount_key#60){++++}-{3:3}, at: iterate_supers+0xa4/0x1d0 fs/super.c:716 1 lock held by syz.1.628/6963: #0: ffff8880735800e0 (&type->s_umount_key#60){++++}-{3:3}, at: iterate_supers+0xa4/0x1d0 fs/super.c:716 1 lock held by syz.2.653/7055: #0: ffff8880735800e0 (&type->s_umount_key#60){++++}-{3:3}, at: iterate_supers+0xa4/0x1d0 fs/super.c:716 1 lock held by syz-executor/7202: #0: ffff8880206a0518 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x157/0xa60 block/bdev.c:820 1 lock held by syz.5.849/7994: ============================================= 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 10/25/2025 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: 20 Comm: ksoftirqd/1 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0010:__lock_acquire+0x123/0x7c60 kernel/locking/lockdep.c:4886 Code: 00 00 00 00 00 fc ff df 48 81 3b 80 df b2 8f 75 03 45 31 e4 44 89 bc 24 c8 00 00 00 41 83 fe 01 77 30 44 89 f0 4c 8d 7c c3 08 <4c> 89 f8 48 c1 e8 03 42 80 3c 00 00 74 12 4c 89 ff e8 d7 33 60 00 RSP: 0018:ffffc90000da69a0 EFLAGS: 00000097 RAX: 0000000000000000 RBX: ffffffff8c11c760 RCX: 1ffff920001b4d58 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8c11c760 RBP: ffffc90000da6bf0 R08: dffffc0000000000 R09: 0000000000000000 R10: fffffbfff1ad33a6 R11: 1ffffffff1ad33a5 R12: 0000000000000000 R13: ffff88813fe68000 R14: 0000000000000000 R15: ffffffff8c11c768 FS: 0000000000000000(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffc77189ff8 CR3: 000000000be8e000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_acquire+0x197/0x3f0 kernel/locking/lockdep.c:5623 rcu_lock_acquire+0x2a/0x30 include/linux/rcupdate.h:313 rcu_read_lock include/linux/rcupdate.h:740 [inline] l3mdev_fib_table+0x14/0x130 include/net/l3mdev.h:136 inet_addr_type_dev_table+0x1b/0x50 net/ipv4/fib_frontend.c:264 ip_route_me_harder+0x2e2/0xf10 net/ipv4/netfilter.c:35 synproxy_send_tcp+0x372/0x6d0 net/netfilter/nf_synproxy_core.c:453 synproxy_send_client_synack+0x886/0xdd0 net/netfilter/nf_synproxy_core.c:506 nft_synproxy_eval_v4+0x36b/0x560 net/netfilter/nft_synproxy.c:59 nft_synproxy_do_eval+0x341/0x570 net/netfilter/nft_synproxy.c:141 expr_call_ops_eval net/netfilter/nf_tables_core.c:198 [inline] nft_do_chain+0x3fc/0x1420 net/netfilter/nf_tables_core.c:238 nft_do_chain_inet+0x22b/0x300 net/netfilter/nft_chain_filter.c:161 nf_hook_entry_hookfn include/linux/netfilter.h:142 [inline] nf_hook_slow+0xb9/0x200 net/netfilter/core.c:584 nf_hook include/linux/netfilter.h:257 [inline] NF_HOOK+0x1cb/0x360 include/linux/netfilter.h:300 NF_HOOK+0x2d6/0x360 include/linux/netfilter.h:302 __netif_receive_skb_one_core net/core/dev.c:5525 [inline] __netif_receive_skb+0xcc/0x290 net/core/dev.c:5639 process_backlog+0x364/0x780 net/core/dev.c:6516 __napi_poll+0xc0/0x430 net/core/dev.c:7075 napi_poll net/core/dev.c:7142 [inline] net_rx_action+0x4a8/0x9c0 net/core/dev.c:7232 handle_softirqs+0x328/0x820 kernel/softirq.c:576 run_ksoftirqd+0x98/0xf0 kernel/softirq.c:943 smpboot_thread_fn+0x4f6/0x970 kernel/smpboot.c:164 kthread+0x436/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287