syzbot

INFO: task syz.4.144:6597 blocked for more than 143 seconds.
      Not tainted 6.11.0-syzkaller-04557-g2f27fce67173 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.144       state:D
 stack:23840 pid:6597  tgid:6536  ppid:6101   flags:0x00000004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5188 [inline]
 __schedule+0x17ae/0x4a10 kernel/sched/core.c:6529
 __schedule_loop kernel/sched/core.c:6606 [inline]
 schedule+0x14b/0x320 kernel/sched/core.c:6621
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6678
 rwsem_down_write_slowpath+0xeeb/0x13b0 kernel/locking/rwsem.c:1178
 __down_write_common kernel/locking/rwsem.c:1306 [inline]
 __down_write kernel/locking/rwsem.c:1315 [inline]
 down_write_nested+0x1e0/0x220 kernel/locking/rwsem.c:1696
 vfs_rename+0x6a2/0xf00 fs/namei.c:4984
 do_renameat2+0xd94/0x13f0 fs/namei.c:5170
 __do_sys_rename fs/namei.c:5217 [inline]
 __se_sys_rename fs/namei.c:5215 [inline]
 __x64_sys_rename+0x82/0x90 fs/namei.c:5215
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f352977def9
RSP: 002b:00007f352a52b038 EFLAGS: 00000246 ORIG_RAX: 0000000000000052
RAX: ffffffffffffffda RBX: 00007f3529936130 RCX: 00007f352977def9
RDX: 0000000000000000 RSI: 0000000020000f40 RDI: 00000000200003c0
RBP: 00007f35297f0b76 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f3529936130 R15: 00007fff00ca8d18
 </TASK>

Showing all locks held in the system:
4 locks held by kworker/u8:0/11:
1 lock held by khungtaskd/30:
 #0: ffffffff8e738a60 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:326 [inline]
 #0: ffffffff8e738a60 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
 #0: ffffffff8e738a60 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6701
3 locks held by kworker/u8:2/35:
 #0: ffff88802f666948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3206 [inline]
 #0: ffff88802f666948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x90a/0x1830 kernel/workqueue.c:3312
 #1: ffffc90000ab7d00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3207 [inline]
 #1: ffffc90000ab7d00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x945/0x1830 kernel/workqueue.c:3312
 #2: ffffffff8fab0488 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xd0/0x16f0 net/ipv6/addrconf.c:4196
3 locks held by kworker/u8:5/1062:
 #0: ffff88801a889148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3206 [inline]
 #0: ffff88801a889148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x90a/0x1830 kernel/workqueue.c:3312
 #1: ffffc90003e3fd00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3207 [inline]
 #1: ffffc90003e3fd00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x945/0x1830 kernel/workqueue.c:3312
 #2: ffffffff8fab0488 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:276
4 locks held by kworker/u8:6/1115:
 #0: ffff88801e6dc948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3206 [inline]
 #0: ffff88801e6dc948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x90a/0x1830 kernel/workqueue.c:3312
 #1: ffffc900039e7d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3207 [inline]
 #1: ffffc900039e7d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x945/0x1830 kernel/workqueue.c:3312
 #2: ffff888022bb60e0 (&type->s_umount_key#54){++++}-{3:3}, at: super_trylock_shared+0x22/0xf0 fs/super.c:562
 #3: ffff8880665392a0 (&sbi->gc_lock){+.+.}-{3:3}, at: f2fs_down_write fs/f2fs/f2fs.h:2175 [inline]
 #3: ffff8880665392a0 (&sbi->gc_lock){+.+.}-{3:3}, at: f2fs_balance_fs+0x5b0/0x7a0 fs/f2fs/segment.c:440
3 locks held by kworker/u8:9/3931:
1 lock held by dhcpcd/4884:
 #0: ffffffff8fab0488 (rtnl_mutex){+.+.}-{3:3}, at: devinet_ioctl+0x2ce/0x1aa0 net/ipv4/devinet.c:1097
2 locks held by getty/4968:
 #0: ffff8880348b20a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
 #1: ffffc9000311b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6a6/0x1e00 drivers/tty/n_tty.c:2211
8 locks held by syz.4.144/6595:
3 locks held by syz.4.144/6597:
 #0: ffff888022bb6420 (sb_writers#12){.+.+}-{0:0}, at: mnt_want_write+0x3f/0x90 fs/namespace.c:515
 #1: ffff88807b335050 (&type->i_mutex_dir_key#8/1){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:850 [inline]
 #1: ffff88807b335050 (&type->i_mutex_dir_key#8/1){+.+.}-{3:3}, at: lock_rename fs/namei.c:3161 [inline]
 #1: ffff88807b335050 (&type->i_mutex_dir_key#8/1){+.+.}-{3:3}, at: do_renameat2+0x62c/0x13f0 fs/namei.c:5105
 #2: ffff88807b330148 (&sb->s_type->i_mutex_key#20/4){+.+.}-{3:3}, at: vfs_rename+0x6a2/0xf00 fs/namei.c:4984
2 locks held by syz-executor/7131:
 #0: ffff88807d5660e0 (&type->s_umount_key#124){++++}-{3:3}, at: __super_lock fs/super.c:56 [inline]
 #0: ffff88807d5660e0 (&type->s_umount_key#124){++++}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline]
 #0: ffff88807d5660e0 (&type->s_umount_key#124){++++}-{3:3}, at: deactivate_super+0xb5/0xf0 fs/super.c:505
 #1: ffff88804ef80278 (&c->state_lock){+.+.}-{3:3}, at: __bch2_fs_stop+0xfd/0x540 fs/bcachefs/super.c:617
2 locks held by syz.4.208/7154:
 #0: ffff888022bb60e0 (&type->s_umount_key#54){++++}-{3:3}, at: __super_lock fs/super.c:58 [inline]
 #0: ffff888022bb60e0 (&type->s_umount_key#54){++++}-{3:3}, at: super_lock+0x27c/0x400 fs/super.c:120
 #1: ffff8880257ce7d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:388 [inline]
 #1: ffff8880257ce7d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: sync_inodes_sb+0x274/0xb40 fs/fs-writeback.c:2797
2 locks held by syz.3.215/7240:
 #0: ffff888022bb60e0 (&type->s_umount_key#54){++++}-{3:3}, at: __super_lock fs/super.c:58 [inline]
 #0: ffff888022bb60e0 (&type->s_umount_key#54){++++}-{3:3}, at: super_lock+0x27c/0x400 fs/super.c:120
 #1: ffff8880257ce7d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:388 [inline]
 #1: ffff8880257ce7d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: sync_inodes_sb+0x274/0xb40 fs/fs-writeback.c:2797
2 locks held by syz.2.228/7415:
 #0: ffff888022bb60e0 (&type->s_umount_key#54){++++}-{3:3}, at: __super_lock fs/super.c:58 [inline]
 #0: ffff888022bb60e0 (&type->s_umount_key#54){++++}-{3:3}, at: super_lock+0x27c/0x400 fs/super.c:120
 #1: ffff8880257ce7d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:388 [inline]
 #1: ffff8880257ce7d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: sync_inodes_sb+0x274/0xb40 fs/fs-writeback.c:2797
3 locks held by bch-reclaim/loo/7633:
1 lock held by syz.0.271/8074:
 #0: ffff88807d5660e0 (&type->s_umount_key#124){++++}-{3:3}, at: __super_lock fs/super.c:58 [inline]
 #0: ffff88807d5660e0 (&type->s_umount_key#124){++++}-{3:3}, at: super_lock+0x27c/0x400 fs/super.c:120
2 locks held by syz.3.324/8239:
 #0: ffff888022bb60e0 (&type->s_umount_key#54){++++}-{3:3}, at: __super_lock fs/super.c:58 [inline]
 #0: ffff888022bb60e0 (&type->s_umount_key#54){++++}-{3:3}, at: super_lock+0x27c/0x400 fs/super.c:120
 #1: ffff8880257ce7d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:388 [inline]
 #1: ffff8880257ce7d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: sync_inodes_sb+0x274/0xb40 fs/fs-writeback.c:2797
2 locks held by syz.0.341/8294:
 #0: ffff888022bb60e0 (&type->s_umount_key#54){++++}-{3:3}, at: __super_lock fs/super.c:58 [inline]
 #0: ffff888022bb60e0 (&type->s_umount_key#54){++++}-{3:3}, at: super_lock+0x27c/0x400 fs/super.c:120
 #1: ffff8880257ce7d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:388 [inline]
 #1: ffff8880257ce7d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: sync_inodes_sb+0x274/0xb40 fs/fs-writeback.c:2797
1 lock held by syz-executor/8305:
 #0: ffffffff8fab0488 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline]
 #0: ffffffff8fab0488 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6643
1 lock held by syz-executor/8317:
 #0: ffffffff8fab0488 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline]
 #0: ffffffff8fab0488 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6643
1 lock held by syz-executor/8374:
 #0: ffffffff8fab0488 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline]
 #0: ffffffff8fab0488 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6643

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

NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.11.0-syzkaller-04557-g2f27fce67173 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:93 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:119
 nmi_cpu_backtrace+0x49c/0x4d0 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:223 [inline]
 watchdog+0xff4/0x1040 kernel/hung_task.c:379
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 5219 Comm: kworker/1:3 Not tainted 6.11.0-syzkaller-04557-g2f27fce67173 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
Workqueue: events kfree_rcu_work
RIP: 0010:preempt_count_add+0x44/0x190 kernel/sched/core.c:5656
Code: 00 00 00 fc ff df 42 0f b6 04 38 84 c0 0f 85 ed 00 00 00 83 3d dc 0b b2 18 00 75 07 65 8b 05 5b d6 a0 7e 65 01 1d 54 d6 a0 7e <48> c7 c0 c0 09 15 9a 48 c1 e8 03 42 0f b6 04 38 84 c0 0f 85 e4 00
RSP: 0018:ffffc90003c2f4b0 EFLAGS: 00000282
RAX: 0000000080000000 RBX: 0000000000000001 RCX: ffffffff9a150903
RDX: dffffc0000000000 RSI: ffffffff81f7beef RDI: 0000000000000001
RBP: ffffc90003c2f5d8 R08: 0000000000000000 R09: ffffc90003c2f690
R10: ffffc90003c2f5f0 R11: ffffffff817f7a40 R12: dffffc0000000000
R13: ffffc90003c2f5a0 R14: ffffffff81f7beef R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8880b8900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f61cd1ff000 CR3: 000000000e534000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <TASK>
 unwind_next_frame+0xb0/0x22d0 arch/x86/kernel/unwind_orc.c:479
 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x118/0x1d0 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:579
 poison_slab_object+0xe0/0x150 mm/kasan/common.c:240
 __kasan_slab_free+0x37/0x60 mm/kasan/common.c:256
 kasan_slab_free include/linux/kasan.h:184 [inline]
 slab_free_hook mm/slub.c:2250 [inline]
 slab_free_freelist_hook mm/slub.c:2279 [inline]
 slab_free_bulk mm/slub.c:4498 [inline]
 kmem_cache_free_bulk+0x1f8/0x370 mm/slub.c:4715
 kfree_bulk include/linux/slab.h:579 [inline]
 kvfree_rcu_bulk+0x24b/0x4e0 kernel/rcu/tree.c:3405
 kfree_rcu_work+0x44b/0x500 kernel/rcu/tree.c:3484
 process_one_work kernel/workqueue.c:3231 [inline]
 process_scheduled_works+0xa2c/0x1830 kernel/workqueue.c:3312
 worker_thread+0x870/0xd30 kernel/workqueue.c:3393
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>