INFO: task syz-executor:4616 blocked for more than 143 seconds.
Not tainted 6.1.142-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor state:D stack:22688 pid:4616 ppid:1 flags:0x00004002
Call Trace:
context_switch kernel/sched/core.c:5244 [inline]
__schedule+0x10e9/0x40d0 kernel/sched/core.c:6561
schedule+0xb9/0x180 kernel/sched/core.c:6637
wb_wait_for_completion+0x162/0x280 fs/fs-writeback.c:191
sync_inodes_sb+0x1b8/0x9e0 fs/fs-writeback.c:2739
sync_filesystem+0x16d/0x220 fs/sync.c:64
generic_shutdown_super+0x6b/0x340 fs/super.c:474
kill_block_super+0x7c/0xe0 fs/super.c:1470
deactivate_locked_super+0x93/0xf0 fs/super.c:332
cleanup_mnt+0x463/0x4f0 fs/namespace.c:1182
task_work_run+0x1ca/0x250 kernel/task_work.c:203
exit_task_work include/linux/task_work.h:39 [inline]
do_exit+0x93e/0x2400 kernel/exit.c:880
do_group_exit+0x217/0x2d0 kernel/exit.c:1022
__do_sys_exit_group kernel/exit.c:1033 [inline]
__se_sys_exit_group kernel/exit.c:1031 [inline]
__x64_sys_exit_group+0x3b/0x40 kernel/exit.c:1031
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f18a478e929
RSP: 002b:00007ffe6b64e938 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 00007f18a48109a9 RCX: 00007f18a478e929
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000001
RBP: 0000000000000027 R08: 00007ffe6b64c6d6 R09: 00007ffe6b64fbf0
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffe6b64fbf0
R13: 00007f18a4810925 R14: 0000555567c2f4a8 R15: 00007ffe6b651db0
Showing all locks held in the system:
1 lock held by rcu_tasks_kthre/12:
#0: ffffffff8c92b430 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xf00 kernel/rcu/tasks.h:517
1 lock held by rcu_tasks_trace/13:
#0: ffffffff8c92bc50 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xf00 kernel/rcu/tasks.h:517
2 locks held by kworker/0:1/14:
#0: ffff888017472138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267
#1: ffffc90000137d00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267
5 locks held by kworker/1:0/22:
#0: ffff88801deaf138 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267
#1: ffffc900001c7d00 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267
#2: ffff8880290e1190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:837 [inline]
#2: ffff8880290e1190 (&dev->mutex){....}-{3:3}, at: hub_event+0x185/0x5210 drivers/usb/core/hub.c:5813
#3: ffff8880290e44f8 (&port_dev->status_lock){+.+.}-{3:3}, at: usb_lock_port drivers/usb/core/hub.c:3172 [inline]
#3: ffff8880290e44f8 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_port_connect drivers/usb/core/hub.c:5385 [inline]
#3: ffff8880290e44f8 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_port_connect_change drivers/usb/core/hub.c:5629 [inline]
#3: ffff8880290e44f8 (&port_dev->status_lock){+.+.}-{3:3}, at: port_event drivers/usb/core/hub.c:5785 [inline]
#3: ffff8880290e44f8 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_event+0x2079/0x5210 drivers/usb/core/hub.c:5867
#4: ffff888028a0ae68 (hcd->address0_mutex){+.+.}-{3:3}, at: hub_port_connect drivers/usb/core/hub.c:5386 [inline]
#4: ffff888028a0ae68 (hcd->address0_mutex){+.+.}-{3:3}, at: hub_port_connect_change drivers/usb/core/hub.c:5629 [inline]
#4: ffff888028a0ae68 (hcd->address0_mutex){+.+.}-{3:3}, at: port_event drivers/usb/core/hub.c:5785 [inline]
#4: ffff888028a0ae68 (hcd->address0_mutex){+.+.}-{3:3}, at: hub_event+0x20a9/0x5210 drivers/usb/core/hub.c:5867
1 lock held by khungtaskd/27:
#0: ffffffff8c92aaa0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
#0: ffffffff8c92aaa0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline]
#0: ffffffff8c92aaa0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6513
2 locks held by kworker/u4:2/38:
2 locks held by dhcpcd/3918:
#0: ffffffff8db1b048 (vlan_ioctl_mutex){+.+.}-{3:3}, at: sock_ioctl+0x273/0x6e0 net/socket.c:1283
#1: ffffffff8db34ee8 (rtnl_mutex){+.+.}-{3:3}, at: vlan_ioctl_handler+0xd2/0x5f0 net/8021q/vlan.c:554
2 locks held by getty/4020:
#0: ffff888030c81098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244
#1: ffffc9000326b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x41b/0x1380 drivers/tty/n_tty.c:2198
5 locks held by kworker/u4:5/4281:
3 locks held by kworker/u4:9/4386:
#0: ffff888017479138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267
#1: ffffc90004727d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267
#2: ffffffff8db34ee8 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xa/0x50 net/core/link_watch.c:263
3 locks held by kworker/1:8/4458:
#0: ffff888017470938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267
#1: ffffc90004897d00 (deferred_process_work){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267
#2: ffffffff8db34ee8 (rtnl_mutex){+.+.}-{3:3}, at: switchdev_deferred_process_work+0xa/0x20 net/switchdev/switchdev.c:104
5 locks held by kworker/u4:13/4571:
#0: ffff888017616938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267
#1: ffffc90004e6fd00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267
#2: ffffffff8db28250 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x132/0xb80 net/core/net_namespace.c:594
#3: ffffffff8db34ee8 (rtnl_mutex){+.+.}-{3:3}, at: default_device_exit_batch+0xe5/0xa50 net/core/dev.c:11477
#4: ffffffff8c930778 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:291 [inline]
#4: ffffffff8c930778 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x455/0x830 kernel/rcu/tree_exp.h:962
3 locks held by kworker/0:11/4602:
#0: ffff88802ffc3538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267
#1: ffffc90004effd00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267
#2: ffffffff8db34ee8 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xc4/0x14d0 net/ipv6/addrconf.c:4137
6 locks held by kworker/0:16/4607:
#0: ffff88801deaf138 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267
#1: ffffc90004d5fd00 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267
#2: ffff888145b15190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:837 [inline]
#2: ffff888145b15190 (&dev->mutex){....}-{3:3}, at: hub_event+0x185/0x5210 drivers/usb/core/hub.c:5813
#3: ffff888145ba84f8 (&port_dev->status_lock){+.+.}-{3:3}, at: usb_lock_port drivers/usb/core/hub.c:3172 [inline]
#3: ffff888145ba84f8 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_port_connect drivers/usb/core/hub.c:5385 [inline]
#3: ffff888145ba84f8 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_port_connect_change drivers/usb/core/hub.c:5629 [inline]
#3: ffff888145ba84f8 (&port_dev->status_lock){+.+.}-{3:3}, at: port_event drivers/usb/core/hub.c:5785 [inline]
#3: ffff888145ba84f8 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_event+0x2079/0x5210 drivers/usb/core/hub.c:5867
#4: ffff888145b29668 (hcd->address0_mutex){+.+.}-{3:3}, at: hub_port_connect drivers/usb/core/hub.c:5386 [inline]
#4: ffff888145b29668 (hcd->address0_mutex){+.+.}-{3:3}, at: hub_port_connect_change drivers/usb/core/hub.c:5629 [inline]
#4: ffff888145b29668 (hcd->address0_mutex){+.+.}-{3:3}, at: port_event drivers/usb/core/hub.c:5785 [inline]
#4: ffff888145b29668 (hcd->address0_mutex){+.+.}-{3:3}, at: hub_event+0x20a9/0x5210 drivers/usb/core/hub.c:5867
#5: ffffffff8d475390 (ehci_cf_port_reset_rwsem){.+.+}-{3:3}, at: hub_port_reset+0x14f/0x1930 drivers/usb/core/hub.c:3029
2 locks held by syz-executor/4616:
#0: ffff88805a4060e0 (&type->s_umount_key#67){++++}-{3:3}, at: deactivate_super+0xa0/0xd0 fs/super.c:362
#1: ffff888024b127d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:362 [inline]
#1: ffff888024b127d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: sync_inodes_sb+0x19c/0x9e0 fs/fs-writeback.c:2737
1 lock held by segctord/5633:
2 locks held by syz-executor/7581:
#0: ffffffff8db94c30 (cb_lock){++++}-{3:3}, at: genl_rcv+0x15/0x40 net/netlink/genetlink.c:860
#1: ffffffff8db34ee8 (rtnl_mutex){+.+.}-{3:3}, at: nl80211_pre_doit+0x5b/0x930 net/wireless/nl80211.c:16235
1 lock held by syz-executor/7911:
#0: ffffffff8db34ee8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
#0: ffffffff8db34ee8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x740/0xed0 net/core/rtnetlink.c:6150
1 lock held by syz.8.620/8009:
#0: ffffffff8db34ee8 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:698 [inline]
#0: ffffffff8db34ee8 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x3d/0x1b0 drivers/net/tun.c:3492
1 lock held by syz.8.620/8010:
#0: ffffffff8db34ee8 (rtnl_mutex){+.+.}-{3:3}, at: devinet_ioctl+0x288/0x1af0 net/ipv4/devinet.c:1081
=============================================
NMI backtrace for cpu 0
CPU: 0 PID: 27 Comm: khungtaskd Not tainted 6.1.142-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
dump_stack_lvl+0x168/0x22e lib/dump_stack.c:106
nmi_cpu_backtrace+0x3f4/0x470 lib/nmi_backtrace.c:111
nmi_trigger_cpumask_backtrace+0x1d4/0x450 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+0xeee/0xf30 kernel/hung_task.c:377
kthread+0x29d/0x330 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 3612 Comm: klogd Not tainted 6.1.142-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:cmpxchg_double_slab+0x1/0x310 mm/slub.c:548
Code: a8 fe ff ff 4c 89 e7 48 c7 c6 91 8b 2f 8c e8 96 ed ea ff 0f 0b 48 89 df 48 c7 c6 91 8b 2f 8c e8 85 ed ea ff 0f 0b 0f 1f 00 55 <41> 57 41 56 41 55 41 54 53 48 83 ec 10 4c 89 c3 49 89 cf 49 89 d4
RSP: 0018:ffffc900032876b8 EFLAGS: 00000206
RAX: 0000000000000000 RBX: ffffea0000b9c200 RCX: 0000000080100007
RDX: ffff88802e70d800 RSI: ffffea0000b9c200 RDI: ffff888018b28140
RBP: 0000000000000000 R08: ffff88802e70b000 R09: 0000000080100006
R10: ffffed1002ef0279 R11: 1ffff11002ef0278 R12: 0000000080100007
R13: 0000000080100006 R14: ffff888018b28140 R15: ffff88802e70d800
FS: 00007f1b78feac80(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c3a43ae CR3: 000000003146c000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
__slab_free+0xa1/0x290 mm/slub.c:3520
qlink_free mm/kasan/quarantine.c:168 [inline]
qlist_free_all+0x76/0xe0 mm/kasan/quarantine.c:187
kasan_quarantine_reduce+0x144/0x160 mm/kasan/quarantine.c:294
__kasan_slab_alloc+0x1e/0x80 mm/kasan/common.c:305
kasan_slab_alloc include/linux/kasan.h:201 [inline]
slab_post_alloc_hook+0x4b/0x480 mm/slab.h:737
slab_alloc_node mm/slub.c:3398 [inline]
kmem_cache_alloc_node+0x14d/0x320 mm/slub.c:3443
__alloc_skb+0xfc/0x7e0 net/core/skbuff.c:505
alloc_skb include/linux/skbuff.h:1271 [inline]
alloc_skb_with_frags+0xa7/0x710 net/core/skbuff.c:6162
sock_alloc_send_pskb+0x853/0x980 net/core/sock.c:2750
unix_dgram_sendmsg+0x592/0x16c0 net/unix/af_unix.c:1937
sock_sendmsg_nosec net/socket.c:718 [inline]
__sock_sendmsg net/socket.c:730 [inline]
__sys_sendto+0x44f/0x5c0 net/socket.c:2153
__do_sys_sendto net/socket.c:2165 [inline]
__se_sys_sendto net/socket.c:2161 [inline]
__x64_sys_sendto+0xda/0xf0 net/socket.c:2161
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f1b7913a407
Code: 48 89 fa 4c 89 df e8 38 aa 00 00 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 1a 5b c3 0f 1f 84 00 00 00 00 00 48 8b 44 24 10 0f 05 <5b> c3 0f 1f 80 00 00 00 00 83 e2 39 83 fa 08 75 de e8 23 ff ff ff
RSP: 002b:00007ffc3794bda0 EFLAGS: 00000202 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f1b78feac80 RCX: 00007f1b7913a407
RDX: 000000000000005e RSI: 00007ffc3794bee0 RDI: 0000000000000003
RBP: 00007ffc3794c310 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000004000 R11: 0000000000000202 R12: 00007ffc3794c328
R13: 00007ffc3794bee0 R14: 0000000000000043 R15: 00007ffc3794bee0