syzbot


INFO: task hung in ocfs2_sync_fs

Status: upstream: reported on 2024/12/26 23:54
Reported-by: syzbot+dcf4f35f4ebbbaa853d6@syzkaller.appspotmail.com
First crash: 40d, last: 4d15h

Sample crash report:
INFO: task syz-executor:4254 blocked for more than 143 seconds.
      Tainted: G        W          6.1.121-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:20912 pid:4254  ppid:1      flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5241 [inline]
 __schedule+0x143f/0x4570 kernel/sched/core.c:6558
 schedule+0xbf/0x180 kernel/sched/core.c:6634
 jbd2_log_wait_commit+0x29b/0x4a0 fs/jbd2/journal.c:710
 ocfs2_sync_fs+0x230/0x380 fs/ocfs2/super.c:412
 sync_filesystem+0x1bc/0x220 fs/sync.c:66
 generic_shutdown_super+0x6b/0x340 fs/super.c:474
 kill_block_super+0x7a/0xe0 fs/super.c:1470
 deactivate_locked_super+0xa0/0x110 fs/super.c:332
 cleanup_mnt+0x490/0x520 fs/namespace.c:1186
 task_work_run+0x246/0x300 kernel/task_work.c:203
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 exit_to_user_mode_loop+0xde/0x100 kernel/entry/common.c:177
 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210
 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
 syscall_exit_to_user_mode+0x60/0x270 kernel/entry/common.c:303
 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:87
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7efd89187057
RSP: 002b:00007ffc9c9b6ea8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007efd892018f4 RCX: 00007efd89187057
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffc9c9b6f60
RBP: 00007ffc9c9b6f60 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffc9c9b7fe0
R13: 00007efd892018f4 R14: 00007ffc9c9b8020 R15: 0000000000000066
 </TASK>

Showing all locks held in the system:
1 lock held by rcu_tasks_kthre/12:
 #0: ffffffff8d32b250 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x34/0xde0 kernel/rcu/tasks.h:543
1 lock held by rcu_tasks_trace/13:
 #0: ffffffff8d32ba70 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x34/0xde0 kernel/rcu/tasks.h:543
1 lock held by khungtaskd/28:
 #0: ffffffff8d32b080 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
 #0: ffffffff8d32b080 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline]
 #0: ffffffff8d32b080 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6510
2 locks held by getty/4009:
 #0: ffff88814d17d098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244
 #1: ffffc9000325e2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6a7/0x1db0 drivers/tty/n_tty.c:2198
1 lock held by syz-executor/4254:
 #0: ffff888053d660e0 (&type->s_umount_key#71){++++}-{3:3}, at: deactivate_super+0xa9/0xe0 fs/super.c:362
3 locks held by kworker/u4:10/4385:
 #0: ffff888017c79138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
 #1: ffffc9000491fd20 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
 #2: ffffffff8e50b1e8 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xa/0x50 net/core/link_watch.c:263
6 locks held by kworker/u4:18/4664:
 #0: ffff888017e16938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
 #1: ffffc900033c7d20 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
 #2: ffffffff8e4fed90 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0xf1/0xbf0 net/core/net_namespace.c:583
 #3: ffff8880276012f8 (&devlink->lock_key#9){+.+.}-{3:3}, at: devlink_pernet_pre_exit+0x132/0x2f0 net/devlink/leftover.c:12500
 #4: ffffffff8e50b1e8 (rtnl_mutex){+.+.}-{3:3}, at: nsim_destroy+0x3a/0x140 drivers/net/netdevsim/netdev.c:381
 #5: ffffffff8d3306b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:291 [inline]
 #5: ffffffff8d3306b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x4f0/0x930 kernel/rcu/tree_exp.h:962
1 lock held by jbd2/loop0-29/6303:
2 locks held by kworker/1:10/6644:
 #0: ffff888017c72138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
 #1: ffffc9000514fd20 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
1 lock held by syz-executor/7298:
 #0: ffffffff8d3306b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:323 [inline]
 #0: ffffffff8d3306b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x360/0x930 kernel/rcu/tree_exp.h:962
1 lock held by syz-executor/8086:
 #0: ffffffff8e50b1e8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
 #0: ffffffff8e50b1e8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x7c1/0xff0 net/core/rtnetlink.c:6147
1 lock held by syz-executor/8116:
 #0: ffffffff8e50b1e8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
 #0: ffffffff8e50b1e8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x7c1/0xff0 net/core/rtnetlink.c:6147
1 lock held by syz-executor/8163:
 #0: ffffffff8e50b1e8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
 #0: ffffffff8e50b1e8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x7c1/0xff0 net/core/rtnetlink.c:6147
2 locks held by dhcpcd-run-hook/8242:

=============================================

NMI backtrace for cpu 0
CPU: 0 PID: 28 Comm: khungtaskd Tainted: G        W          6.1.121-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Call Trace:
 <TASK>
 __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+0x1ae/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
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 26 Comm: kworker/1:1 Tainted: G        W          6.1.121-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Workqueue: events_power_efficient wg_ratelimiter_gc_entries
RIP: 0010:check_preemption_disabled+0x48/0x110 lib/smp_processor_id.c:55
Code: 4f 75 65 8b 05 31 12 50 75 a9 ff ff ff 7f 74 22 65 48 8b 04 25 28 00 00 00 48 3b 44 24 08 0f 85 c7 00 00 00 89 d8 48 83 c4 10 <5b> 41 5c 41 5e 41 5f c3 48 c7 04 24 00 00 00 00 9c 8f 04 24 f7 04
RSP: 0018:ffffc90000a1fa70 EFLAGS: 00000082
RAX: 0000000000000001 RBX: 0000000000000001 RCX: ffff888019e4bb80
RDX: 0000000000000000 RSI: ffffffff8b0c1020 RDI: ffffffff8b5e6400
RBP: 00000000ffffffff R08: dffffc0000000000 R09: fffffbfff1ba21cd
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000246
R13: ffff888019e4bb80 R14: 00000000ffffffff R15: ffffffff8d32b000
FS:  0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f084fa3f290 CR3: 000000000d08e000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <TASK>
 lockdep_recursion_inc kernel/locking/lockdep.c:462 [inline]
 lock_is_held_type+0x76/0x180 kernel/locking/lockdep.c:5704
 lock_is_held include/linux/lockdep.h:283 [inline]
 __might_resched+0xf0/0x780 kernel/sched/core.c:9917
 wg_ratelimiter_gc_entries+0x3c9/0x470 drivers/net/wireguard/ratelimiter.c:78
 process_one_work+0x8a9/0x11d0 kernel/workqueue.c:2292
 worker_thread+0xa47/0x1200 kernel/workqueue.c:2439
 kthread+0x28d/0x320 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/12/26 23:53 linux-6.1.y 29f02ec58a94 d3ccff63 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: task hung in ocfs2_sync_fs
2024/12/26 23:53 linux-6.1.y 29f02ec58a94 d3ccff63 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: task hung in ocfs2_sync_fs
2025/01/31 12:13 linux-6.1.y 75cefdf153f5 4c6ac32f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 INFO: task hung in ocfs2_sync_fs
* Struck through repros no longer work on HEAD.