INFO: task syz-executor:17619 blocked for more than 143 seconds. Not tainted 6.16.0-rc5-next-20250708-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:20904 pid:17619 tgid:17619 ppid:1 task_flags:0x400140 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5314 [inline] __schedule+0x16f5/0x4d00 kernel/sched/core.c:6697 __schedule_loop kernel/sched/core.c:6775 [inline] schedule+0x165/0x360 kernel/sched/core.c:6790 io_schedule+0x80/0xd0 kernel/sched/core.c:7635 folio_wait_bit_common+0x6b0/0xb90 mm/filemap.c:1317 __folio_lock mm/filemap.c:1675 [inline] folio_lock include/linux/pagemap.h:1114 [inline] __filemap_get_folio+0x139/0xaf0 mm/filemap.c:1929 truncate_inode_pages_range+0x3ed/0xda0 mm/truncate.c:388 evict+0x517/0x9c0 fs/inode.c:812 dispose_list fs/inode.c:852 [inline] evict_inodes+0x636/0x6c0 fs/inode.c:906 generic_shutdown_super+0x9a/0x2c0 fs/super.c:628 kill_block_super+0x44/0x90 fs/super.c:1755 deactivate_locked_super+0xb9/0x130 fs/super.c:474 cleanup_mnt+0x425/0x4c0 fs/namespace.c:1378 task_work_run+0x1d4/0x260 kernel/task_work.c:227 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop+0xec/0x110 kernel/entry/common.c:43 exit_to_user_mode_prepare include/linux/irq-entry-common.h:208 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline] do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f070918fc57 RSP: 002b:00007ffcb3074258 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007f0709210925 RCX: 00007f070918fc57 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffcb3074310 RBP: 00007ffcb3074310 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffcb30753a0 R13: 00007f0709210925 R14: 000000000015ca34 R15: 00007ffcb30753e0 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8e13bfa0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e13bfa0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8e13bfa0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6770 1 lock held by syslogd/5202: #0: ffff8880b8639f98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0xad/0x140 kernel/sched/core.c:614 1 lock held by dhcpcd/5515: #0: ffffffff8f533e08 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #0: ffffffff8f533e08 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_delroute+0x107/0x2f0 net/ipv4/fib_frontend.c:887 2 locks held by getty/5610: #0: ffff88803408e0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 1 lock held by udevd/9530: 1 lock held by syz-executor/17619: #0: ffff8880786580e0 (&type->s_umount_key#109){+.+.}-{4:4}, at: __super_lock fs/super.c:57 [inline] #0: ffff8880786580e0 (&type->s_umount_key#109){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline] #0: ffff8880786580e0 (&type->s_umount_key#109){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:506 4 locks held by kworker/u8:14/19740: #0: ffff88801b2fe948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #0: ffff88801b2fe948 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3322 #1: ffffc9000517fbc0 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3215 [inline] #1: ffffc9000517fbc0 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3322 #2: ffffffff8f527030 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf7/0x800 net/core/net_namespace.c:658 #3: ffffffff8f533e08 (rtnl_mutex){+.+.}-{4:4}, at: mpls_net_exit+0x79/0x270 net/mpls/af_mpls.c:2706 2 locks held by syz.4.3387/21255: #0: ffffffff8f533e08 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:633 [inline] #0: ffffffff8f533e08 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x3e/0x1c0 drivers/net/tun.c:3395 #1: ffffffff8e141af8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline] #1: ffffffff8e141af8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f6/0x730 kernel/rcu/tree_exp.h:967 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.16.0-rc5-next-20250708-syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:328 [inline] watchdog+0xfee/0x1030 kernel/hung_task.c:491 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 10941 Comm: kworker/u8:0 Not tainted 6.16.0-rc5-next-20250708-syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Workqueue: bat_events batadv_mcast_mla_update RIP: 0010:__kasan_check_byte+0x0/0x40 mm/kasan/common.c:555 Code: 44 24 48 a8 01 0f 84 da fe ff ff 48 ff c8 49 89 c4 e9 cf fe ff ff 0f 1f 40 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <66> 0f 1f 00 41 56 53 48 89 f3 49 89 fe e8 5e 14 00 00 84 c0 75 16 RSP: 0018:ffffc90002e97330 EFLAGS: 00000202 RAX: 0000000000000001 RBX: 0000000000000000 RCX: 7c27f51efcf6b500 RDX: 0000000000000000 RSI: ffffffff81729c72 RDI: ffffffff8e13bfa0 RBP: ffffffff81729c55 R08: 0000000000000000 R09: 0000000000000000 R10: ffffc90002e974f8 R11: ffffffff81ac6fc0 R12: 0000000000000002 R13: ffffffff8e13bfa0 R14: 0000000000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff888125bd7000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fabcfb82178 CR3: 00000000752b6000 CR4: 00000000003526f0 Call Trace: kasan_check_byte include/linux/kasan.h:399 [inline] lock_acquire+0x8d/0x360 kernel/locking/lockdep.c:5845 rcu_lock_acquire include/linux/rcupdate.h:331 [inline] rcu_read_lock include/linux/rcupdate.h:841 [inline] class_rcu_constructor include/linux/rcupdate.h:1155 [inline] unwind_next_frame+0xc2/0x2390 arch/x86/kernel/unwind_orc.c:479 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:394 kasan_kmalloc include/linux/kasan.h:260 [inline] __kmalloc_cache_noprof+0x230/0x3d0 mm/slub.c:4396 kmalloc_noprof include/linux/slab.h:905 [inline] batadv_mcast_mla_meshif_get_ipv6 net/batman-adv/multicast.c:477 [inline] batadv_mcast_mla_meshif_get net/batman-adv/multicast.c:535 [inline] __batadv_mcast_mla_update net/batman-adv/multicast.c:911 [inline] batadv_mcast_mla_update+0x18ca/0x3670 net/batman-adv/multicast.c:948 process_one_work kernel/workqueue.c:3239 [inline] process_scheduled_works+0xade/0x17b0 kernel/workqueue.c:3322 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3403 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245