INFO: task syz.2.688:7220 blocked for more than 143 seconds. Not tainted 6.1.105-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.688 state:D stack:25248 pid:7220 ppid:5435 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5241 [inline] __schedule+0x143f/0x4570 kernel/sched/core.c:6558 schedule+0xbf/0x180 kernel/sched/core.c:6634 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6693 __mutex_lock_common kernel/locking/mutex.c:679 [inline] __mutex_lock+0x6b9/0xd80 kernel/locking/mutex.c:747 exfat_sync_fs+0x67/0x100 fs/exfat/super.c:65 iterate_supers+0x127/0x1e0 fs/super.c:757 ksys_sync+0xd7/0x1c0 fs/sync.c:104 __do_sys_sync+0xa/0x10 fs/sync.c:113 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f504a1799b9 RSP: 002b:00007f5049fff038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2 RAX: ffffffffffffffda RBX: 00007f504a316058 RCX: 00007f504a1799b9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007f504a1e78d8 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f504a316058 R15: 00007ffc4de83c58 Showing all locks held in the system: 1 lock held by rcu_tasks_kthre/12: #0: ffffffff8d32b190 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xe30 kernel/rcu/tasks.h:516 1 lock held by rcu_tasks_trace/13: #0: ffffffff8d32b990 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xe30 kernel/rcu/tasks.h:516 1 lock held by khungtaskd/27: #0: ffffffff8d32afc0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] #0: ffffffff8d32afc0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline] #0: ffffffff8d32afc0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6494 2 locks held by getty/3389: #0: ffff88807f1d8098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244 #1: ffffc900031262f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6a7/0x1db0 drivers/tty/n_tty.c:2198 5 locks held by kworker/u4:12/3782: #0: ffff888012a1e938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #1: ffffc90004a67d20 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #2: ffffffff8e4ec010 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0xf1/0xb60 net/core/net_namespace.c:566 #3: ffffffff8e4f8368 (rtnl_mutex){+.+.}-{3:3}, at: ip_tunnel_delete_nets+0xc9/0x330 net/ipv4/ip_tunnel.c:1148 #4: ffffffff8d3305b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:291 [inline] #4: ffffffff8d3305b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x4f0/0x930 kernel/rcu/tree_exp.h:962 3 locks held by kworker/u4:15/4321: #0: ffff888012879138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #1: ffffc900035afd20 ((work_completion)(&map->work)){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #2: ffffffff8d3305b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:323 [inline] #2: ffffffff8d3305b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x360/0x930 kernel/rcu/tree_exp.h:962 2 locks held by kworker/1:16/4708: #0: ffff888012872138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #1: ffffc900044cfd20 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 3 locks held by syz-executor/6312: 2 locks held by syz.2.688/7220: #0: ffff8880799860e0 (&type->s_umount_key#104){++++}-{3:3}, at: iterate_supers+0xac/0x1e0 fs/super.c:755 #1: ffff888064ebe0e0 (&sbi->s_lock#3){+.+.}-{3:3}, at: exfat_sync_fs+0x67/0x100 fs/exfat/super.c:65 2 locks held by syz.0.726/7414: #0: ffff8880799860e0 (&type->s_umount_key#104){++++}-{3:3}, at: iterate_supers+0xac/0x1e0 fs/super.c:755 #1: ffff888064ebe0e0 (&sbi->s_lock#3){+.+.}-{3:3}, at: exfat_sync_fs+0x67/0x100 fs/exfat/super.c:65 2 locks held by kworker/u4:3/7689: #0: ffff888012879138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #1: ffffc9000585fd20 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 2 locks held by syz.1.791/7820: #0: ffff8880799860e0 (&type->s_umount_key#104){++++}-{3:3}, at: iterate_supers+0xac/0x1e0 fs/super.c:755 #1: ffff888064ebe0e0 (&sbi->s_lock#3){+.+.}-{3:3}, at: exfat_sync_fs+0x67/0x100 fs/exfat/super.c:65 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 27 Comm: khungtaskd Not tainted 6.1.105-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106 nmi_cpu_backtrace+0x4e1/0x560 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x1b0/0x3f0 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline] watchdog+0xf88/0xfd0 kernel/hung_task.c:377 kthread+0x28d/0x320 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 3073 Comm: syslogd Not tainted 6.1.105-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024 RIP: 0010:arch_stack_walk+0x101/0x140 arch/x86/kernel/stacktrace.c:27 Code: 05 1f 09 00 83 bd 70 ff ff ff 00 74 32 48 8d 9d 70 ff ff ff 48 89 df e8 9d f9 08 00 48 85 c0 74 1e 4c 89 f7 48 89 c6 41 ff d5 <84> c0 74 11 48 89 df e8 a3 fa 08 00 83 bd 70 ff ff ff 00 75 d5 65 RSP: 0018:ffffc9000306f480 EFLAGS: 00000286 RAX: 0000000000000001 RBX: ffffc9000306f480 RCX: ffffffff8fdae000 RDX: dffffc0000000000 RSI: ffffffff8ac000cc RDI: ffffc9000306f56c RBP: ffffc9000306f510 R08: 000000000000000b R09: ffffc9000306f570 R10: 0000000000000000 R11: dffffc0000000001 R12: ffff88807e7c5940 R13: ffffffff81785b50 R14: ffffc9000306f560 R15: 0000000000000000 FS: 00007f68b37aa380(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020404030 CR3: 000000007f512000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: stack_trace_save+0x113/0x1c0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:52 kasan_save_free_info+0x27/0x40 mm/kasan/generic.c:516 ____kasan_slab_free+0xd6/0x120 mm/kasan/common.c:236 kasan_slab_free include/linux/kasan.h:177 [inline] slab_free_hook mm/slub.c:1724 [inline] slab_free_freelist_hook mm/slub.c:1750 [inline] slab_free mm/slub.c:3661 [inline] __kmem_cache_free+0x25c/0x3c0 mm/slub.c:3674 skb_free_head net/core/skbuff.c:762 [inline] skb_release_data+0x5de/0x7a0 net/core/skbuff.c:791 skb_release_all net/core/skbuff.c:856 [inline] __kfree_skb net/core/skbuff.c:870 [inline] consume_skb+0xa3/0x140 net/core/skbuff.c:1035 __unix_dgram_recvmsg+0xcb3/0x1260 net/unix/af_unix.c:2514 sock_recvmsg_nosec net/socket.c:1022 [inline] sock_recvmsg net/socket.c:1040 [inline] sock_read_iter+0x3b2/0x4b0 net/socket.c:1121 call_read_iter include/linux/fs.h:2259 [inline] new_sync_read fs/read_write.c:389 [inline] vfs_read+0x88d/0xbf0 fs/read_write.c:470 ksys_read+0x19c/0x2c0 fs/read_write.c:613 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f68b38feb6a Code: 00 3d 00 00 41 00 75 0d 50 48 8d 3d 2d 08 0a 00 e8 ea 7d 01 00 31 c0 e9 07 ff ff ff 64 8b 04 25 18 00 00 00 85 c0 75 1b 0f 05 <48> 3d 00 f0 ff ff 76 6c 48 8b 15 8f a2 0d 00 f7 d8 64 89 02 48 83 RSP: 002b:00007ffc1f702f68 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007f68b38feb6a RDX: 00000000000000ff RSI: 000055af28a1f950 RDI: 0000000000000000 RBP: 000055af28a1f910 R08: 0000000000000001 R09: 0000000000000000 R10: 00007f68b3a9d3a3 R11: 0000000000000246 R12: 000055af28a1f999 R13: 000055af28a1f950 R14: 0000000000000000 R15: 00007f68b3adba80