syzbot


INFO: task hung in caif_exit_net (6)

Status: auto-obsoleted due to no activity on 2026/06/28 01:54
Subsystems: net
Labels: prio:high
[Documentation on labels]
First crash: 200d, last: 91d
✨ AI Jobs (1)
ID Workflow Result Correct Bug Created Started Finished Revision Error
04132c2b-b547-4ed2-bc8f-8bef72123148 assessment-security DenialOfService: ✅ Exploitable: ❌ FilesystemTrigger: ❌ NetworkTrigger: ❌ PeripheralTrigger: ❌ RemoteTrigger: ✅ Unprivileged: ❌ UserNamespace: ❌ VMGuestTrigger: ❌ VMHostTrigger: ❌ INFO: task hung in caif_exit_net (6) 2026/05/23 12:10 2026/05/23 12:10 2026/05/23 12:35 c69befb30ac10e158cc9d1557b508ee3f0eca1de

			
		
Similar bugs (5)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in caif_exit_net (3) net 1 1 1326d 1326d 0/29 auto-obsoleted due to no activity on 2023/02/10 18:53
upstream INFO: task hung in caif_exit_net (2) net 1 1 1714d 1714d 0/29 auto-closed as invalid on 2022/01/16 13:12
upstream INFO: task hung in caif_exit_net (5) net 1 3 543d 624d 0/29 auto-obsoleted due to no activity on 2025/04/01 16:47
upstream INFO: task hung in caif_exit_net (4) net 1 6 741d 768d 0/29 auto-obsoleted due to no activity on 2024/09/16 03:37
upstream INFO: task hung in caif_exit_net net 1 1 2118d 2118d 0/29 auto-closed as invalid on 2020/12/08 10:12

Sample crash report:
INFO: task kworker/u10:23:11111 blocked for more than 143 seconds.
      Tainted: G     U       L      syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u10:23  state:D stack:23336 pid:11111 tgid:11111 ppid:2      task_flags:0x4208160 flags:0x00080000
Workqueue: netns cleanup_net
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5298 [inline]
 __schedule+0xfee/0x6120 kernel/sched/core.c:6911
 __schedule_loop kernel/sched/core.c:6993 [inline]
 schedule+0xdd/0x390 kernel/sched/core.c:7008
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7065
 __mutex_lock_common kernel/locking/mutex.c:692 [inline]
 __mutex_lock+0xc9a/0x1b90 kernel/locking/mutex.c:776
 caif_exit_net+0x60/0x3a0 net/caif/caif_dev.c:528
 ops_exit_list net/core/net_namespace.c:199 [inline]
 ops_undo_list+0x2ee/0xab0 net/core/net_namespace.c:252
 cleanup_net+0x499/0x920 net/core/net_namespace.c:704
 process_one_work+0xa23/0x19a0 kernel/workqueue.c:3276
 process_scheduled_works kernel/workqueue.c:3359 [inline]
 worker_thread+0x5ef/0xe50 kernel/workqueue.c:3440
 kthread+0x370/0x450 kernel/kthread.c:436
 ret_from_fork+0x754/0xd80 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
INFO: task syz-executor:16644 blocked for more than 144 seconds.
      Tainted: G     U       L      syzkaller #0
      Blocked by coredump.
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:23656 pid:16644 tgid:16644 ppid:1      task_flags:0x40054c flags:0x00080003
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5298 [inline]
 __schedule+0xfee/0x6120 kernel/sched/core.c:6911
 __schedule_loop kernel/sched/core.c:6993 [inline]
 schedule+0xdd/0x390 kernel/sched/core.c:7008
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7065
 __mutex_lock_common kernel/locking/mutex.c:692 [inline]
 __mutex_lock+0xc9a/0x1b90 kernel/locking/mutex.c:776
 tun_detach drivers/net/tun.c:634 [inline]
 tun_chr_close+0x38/0x220 drivers/net/tun.c:3436
 __fput+0x3ff/0xb40 fs/file_table.c:469
 task_work_run+0x150/0x240 kernel/task_work.c:233
 exit_task_work include/linux/task_work.h:40 [inline]
 do_exit+0x8b8/0x2b60 kernel/exit.c:976
 do_group_exit+0xd5/0x2a0 kernel/exit.c:1118
 get_signal+0x1ec7/0x21e0 kernel/signal.c:3034
 arch_do_signal_or_restart+0x91/0x770 arch/x86/kernel/signal.c:337
 __exit_to_user_mode_loop kernel/entry/common.c:64 [inline]
 exit_to_user_mode_loop+0x86/0x4a0 kernel/entry/common.c:98
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
 syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:325 [inline]
 do_syscall_64+0x668/0xf80 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f76d515cfce
RSP: 002b:00007ffc1ad9a638 EFLAGS: 00000246 ORIG_RAX: 000000000000003d
RAX: 000000000000047c RBX: 0000555589160500 RCX: 00007f76d515cfce
RDX: 0000000040000000 RSI: 00007ffc1ad9a6dc RDI: ffffffffffffffff
RBP: 00007ffc1ad9a6dc R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000000011d
R13: 00005555891739f0 R14: 0000000000131104 R15: 00007ffc1ad9a730
 </TASK>
INFO: task syz-executor:17199 blocked for more than 145 seconds.
      Tainted: G     U       L      syzkaller #0
      Blocked by coredump.
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:24104 pid:17199 tgid:17199 ppid:1      task_flags:0x40054c flags:0x00080003
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5298 [inline]
 __schedule+0xfee/0x6120 kernel/sched/core.c:6911
 __schedule_loop kernel/sched/core.c:6993 [inline]
 schedule+0xdd/0x390 kernel/sched/core.c:7008
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7065
 __mutex_lock_common kernel/locking/mutex.c:692 [inline]
 __mutex_lock+0xc9a/0x1b90 kernel/locking/mutex.c:776
 tun_detach drivers/net/tun.c:634 [inline]
 tun_chr_close+0x38/0x220 drivers/net/tun.c:3436
 __fput+0x3ff/0xb40 fs/file_table.c:469
 task_work_run+0x150/0x240 kernel/task_work.c:233
 exit_task_work include/linux/task_work.h:40 [inline]
 do_exit+0x8b8/0x2b60 kernel/exit.c:976
 do_group_exit+0xd5/0x2a0 kernel/exit.c:1118
 get_signal+0x1ec7/0x21e0 kernel/signal.c:3034
 arch_do_signal_or_restart+0x91/0x770 arch/x86/kernel/signal.c:337
 __exit_to_user_mode_loop kernel/entry/common.c:64 [inline]
 exit_to_user_mode_loop+0x86/0x4a0 kernel/entry/common.c:98
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
 syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:325 [inline]
 do_syscall_64+0x668/0xf80 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ff45835cfce
RSP: 002b:00007fff4274fec8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e6
RAX: 0000000000000000 RBX: 0000555594be7500 RCX: 00007ff45835cfce
RDX: 00007fff4274ff20 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007fff4274ff8c R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000000010d
R13: 000000000000005d R14: 000000000013742b R15: 00007fff4274ffe0
 </TASK>
INFO: task syz-executor:19736 blocked for more than 145 seconds.
      Tainted: G     U       L      syzkaller #0
      Blocked by coredump.
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:24264 pid:19736 tgid:19736 ppid:1      task_flags:0x40054c flags:0x00080003
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5298 [inline]
 __schedule+0xfee/0x6120 kernel/sched/core.c:6911
 __schedule_loop kernel/sched/core.c:6993 [inline]
 schedule+0xdd/0x390 kernel/sched/core.c:7008
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7065
 __mutex_lock_common kernel/locking/mutex.c:692 [inline]
 __mutex_lock+0xc9a/0x1b90 kernel/locking/mutex.c:776
 tun_detach drivers/net/tun.c:634 [inline]
 tun_chr_close+0x38/0x220 drivers/net/tun.c:3436
 __fput+0x3ff/0xb40 fs/file_table.c:469
 task_work_run+0x150/0x240 kernel/task_work.c:233
 exit_task_work include/linux/task_work.h:40 [inline]
 do_exit+0x8b8/0x2b60 kernel/exit.c:976
 do_group_exit+0xd5/0x2a0 kernel/exit.c:1118
 get_signal+0x1ec7/0x21e0 kernel/signal.c:3034
 arch_do_signal_or_restart+0x91/0x770 arch/x86/kernel/signal.c:337
 __exit_to_user_mode_loop kernel/entry/common.c:64 [inline]
 exit_to_user_mode_loop+0x86/0x4a0 kernel/entry/common.c:98
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
 syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:325 [inline]
 do_syscall_64+0x668/0xf80 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f546475cfce
RSP: 002b:00007ffcbe751ed8 EFLAGS: 00000246
 ORIG_RAX: 0000000000000000
RAX: fffffffffffffe00 RBX: 000055559086e500 RCX: 00007f546475cfce
RDX: 0000000000000030 RSI: 00007ffcbe751fd0 RDI: 00000000000000f9
RBP: 00007ffcbe751f7c R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000000007d
R13: 0000000000000048 R14: 0000000000137421 R15: 00007ffcbe751fd0
 </TASK>

Showing all locks held in the system:
1 lock held by pool_workqueue_/3:
 #0: ffffffff8e7f30f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x27f/0x3c0 kernel/rcu/tree_exp.h:311
1 lock held by khungtaskd/30:
 #0: ffffffff8e7e74e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
 #0: ffffffff8e7e74e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
 #0: ffffffff8e7e74e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6775
1 lock held by khugepaged/37:
 #0: ffffffff8e9383a8 (lock#5){+.+.}-{4:4}, at: __lru_add_drain_all+0x6a/0x650 mm/swap.c:840
3 locks held by kworker/1:1/42:
 #0: ffff88813fe63148 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x1310/0x19a0 kernel/workqueue.c:3251
 #1: ffffc90000b27d08 ((work_completion)(&(&ovs_net->masks_rebalance)->work)){+.+.}-{0:0}, at: process_one_work+0x988/0x19a0 kernel/workqueue.c:3252
 #2: ffffffff90b7d528 (ovs_mutex){+.+.}-{4:4}, at: ovs_lock net/openvswitch/datapath.c:108 [inline]
 #2: ffffffff90b7d528 (ovs_mutex){+.+.}-{4:4}, at: ovs_dp_masks_rebalance+0x24/0xf0 net/openvswitch/datapath.c:2559
1 lock held by udevd/5195:
4 locks held by syz-executor/5812:
 #0: ffff88807872e1c8 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0x11d/0x590 mm/mmap_lock.c:310
 #1: ffff888034510518 (sb_pagefaults){.+.+}-{0:0}, at: do_page_mkwrite+0x17a/0x440 mm/memory.c:3589
 #2: ffff88807ea398b0 (mapping.invalidate_lock#2){++++}-{4:4}, at: filemap_invalidate_lock_shared include/linux/fs.h:1093 [inline]
 #2: ffff88807ea398b0 (mapping.invalidate_lock#2){++++}-{4:4}, at: ext4_page_mkwrite+0x36c/0x1980 fs/ext4/inode.c:6618
 #3: ffff88807ea395a0 (&ei->i_data_sem){++++}-{4:4}, at: ext4_da_map_blocks fs/ext4/inode.c:1954 [inline]
 #3: ffff88807ea395a0 (&ei->i_data_sem){++++}-{4:4}, at: ext4_da_get_block_prep+0x738/0x1240 fs/ext4/inode.c:2020
3 locks held by kworker/1:3/5828:
 #0: ffff88813fe63148 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x1310/0x19a0 kernel/workqueue.c:3251
 #1: ffffc900040d7d08 ((work_completion)(&(&ovs_net->masks_rebalance)->work)){+.+.}-{0:0}, at: process_one_work+0x988/0x19a0 kernel/workqueue.c:3252
 #2: ffffffff90b7d528 (ovs_mutex){+.+.}-{4:4}, at: ovs_lock net/openvswitch/datapath.c:108 [inline]
 #2: ffffffff90b7d528 (ovs_mutex){+.+.}-{4:4}, at: ovs_dp_masks_rebalance+0x24/0xf0 net/openvswitch/datapath.c:2559
3 locks held by kworker/1:5/5915:
 #0: ffff88813fe63148 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x1310/0x19a0 kernel/workqueue.c:3251
 #1: ffffc90004867d08 ((work_completion)(&(&ovs_net->masks_rebalance)->work)){+.+.}-{0:0}, at: process_one_work+0x988/0x19a0 kernel/workqueue.c:3252
 #2: ffffffff90b7d528 (ovs_mutex){+.+.}-{4:4}, at: ovs_lock net/openvswitch/datapath.c:108 [inline]
 #2: ffffffff90b7d528 (ovs_mutex){+.+.}-{4:4}, at: ovs_dp_masks_rebalance+0x24/0xf0 net/openvswitch/datapath.c:2559
3 locks held by kworker/u10:8/9979:
3 locks held by kworker/u10:10/9981:
5 locks held by kworker/u10:15/9986:
1 lock held by syz.0.878/10082:
4 locks held by kworker/u10:23/11111:
 #0: ffff88801c6ae948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x1310/0x19a0 kernel/workqueue.c:3251
 #1: ffffc900038c7d08 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x988/0x19a0 kernel/workqueue.c:3252
 #2: ffffffff905fb950 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xb8/0x920 net/core/net_namespace.c:675
 #3: ffffffff906141a8 (rtnl_mutex){+.+.}-{4:4}, at: caif_exit_net+0x60/0x3a0 net/caif/caif_dev.c:528
3 locks held by kworker/u10:24/14768:
3 locks held by kworker/u10:28/14773:
3 locks held by kworker/u10:34/14788:
3 locks held by kworker/u10:35/14789:
1 lock held by syz-executor/16644:
 #0: ffffffff906141a8 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline]
 #0: ffffffff906141a8 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x38/0x220 drivers/net/tun.c:3436
1 lock held by syz-executor/17199:
 #0: ffffffff906141a8 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline]
 #0: ffffffff906141a8 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x38/0x220 drivers/net/tun.c:3436
4 locks held by kworker/1:2/17695:
 #0: ffff88813fe61d48 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_one_work+0x1310/0x19a0 kernel/workqueue.c:3251
 #1: ffffc90003ddfd08 ((reg_check_chans).work){+.+.}-{0:0}, at: process_one_work+0x988/0x19a0 kernel/workqueue.c:3252
 #2: ffffffff906141a8 (rtnl_mutex){+.+.}-{4:4}, at: reg_check_chans_work+0x91/0x11d0 net/wireless/reg.c:2462
 #3: ffff88807d3e8788 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: class_wiphy_constructor include/net/cfg80211.h:6441 [inline]
 #3: ffff88807d3e8788 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: reg_leave_invalid_chans net/wireless/reg.c:2450 [inline]
 #3: ffff88807d3e8788 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: reg_check_chans_work+0x12f/0x11d0 net/wireless/reg.c:2465
1 lock held by syz-executor/19736:
 #0: ffffffff906141a8 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline]
 #0: ffffffff906141a8 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x38/0x220 drivers/net/tun.c:3436
2 locks held by kworker/0:0/21531:
2 locks held by syz.5.3371/21882:
 #0: ffffffff905fb950 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x451/0x7c0 net/core/net_namespace.c:577
 #1: ffffffff906141a8 (rtnl_mutex){+.+.}-{4:4}, at: netdev_wait_allrefs_any net/core/dev.c:11600 [inline]
 #1: ffffffff906141a8 (rtnl_mutex){+.+.}-{4:4}, at: netdev_run_todo+0xd60/0x12c0 net/core/dev.c:11712
3 locks held by kworker/u10:0/21918:
3 locks held by kworker/1:0/21922:
 #0: ffff88813fe63148 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x1310/0x19a0 kernel/workqueue.c:3251
 #1: ffffc90004987d08 ((work_completion)(&(&ovs_net->masks_rebalance)->work)){+.+.}-{0:0}, at: process_one_work+0x988/0x19a0 kernel/workqueue.c:3252
 #2: ffffffff90b7d528 (ovs_mutex){+.+.}-{4:4}, at: ovs_lock net/openvswitch/datapath.c:108 [inline]
 #2: ffffffff90b7d528 (ovs_mutex){+.+.}-{4:4}, at: ovs_dp_masks_rebalance+0x24/0xf0 net/openvswitch/datapath.c:2559
3 locks held by kworker/1:4/21923:
 #0: ffff88813fe63148 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x1310/0x19a0 kernel/workqueue.c:3251
 #1: ffffc900053c7d08 ((work_completion)(&(&ovs_net->masks_rebalance)->work)){+.+.}-{0:0}, at: process_one_work+0x988/0x19a0 kernel/workqueue.c:3252
 #2: ffffffff90b7d528 (ovs_mutex){+.+.}-{4:4}, at: ovs_lock net/openvswitch/datapath.c:108 [inline]
 #2: ffffffff90b7d528 (ovs_mutex){+.+.}-{4:4}, at: ovs_dp_masks_rebalance+0x24/0xf0 net/openvswitch/datapath.c:2559
3 locks held by kworker/1:6/21924:
 #0: ffff88813fe63148 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x1310/0x19a0 kernel/workqueue.c:3251
 #1: ffffc900051bfd08 ((work_completion)(&(&ovs_net->masks_rebalance)->work)){+.+.}-{0:0}, at: process_one_work+0x988/0x19a0 kernel/workqueue.c:3252
 #2: ffffffff90b7d528 (ovs_mutex){+.+.}-{4:4}, at: ovs_lock net/openvswitch/datapath.c:108 [inline]
 #2: ffffffff90b7d528 (ovs_mutex){+.+.}-{4:4}, at: ovs_dp_masks_rebalance+0x24/0xf0 net/openvswitch/datapath.c:2559
4 locks held by kworker/1:8/21927:
 #0: ffff888059346548 ((wq_completion)wg-kex-wg0#20){+.+.}-{0:0}, at: process_one_work+0x1310/0x19a0 kernel/workqueue.c:3251
 #1: ffffc900054cfd08 ((work_completion)(&({ do { const void __seg_gs *__vpp_verify = (typeof((worker) + 0))((void *)0); (void)__vpp_verify; } while (0); ({ unsigned long __ptr; __asm__ ("" : "=r"(__ptr) : "0"((__typeof_unqual__(*((worker))) *)(( unsigned long)((worker))))); (typeof((__typeof_unqual__(*((worker))) *)(( unsigned long)((worker))))) (__ptr + (((__per_cpu_offset[(cpu)])))); }); })->work)){+.+.}-{0:0}, at: process_one_work+0x988/0x19a0 kernel/workqueue.c:3252
 #2: ffff88807a5c1348 (&wg->static_identity.lock){++++}-{4:4}, at: wg_noise_handshake_consume_initiation+0x1c2/0x860 drivers/net/wireguard/noise.c:598
 #3: ffff88803320a0f0 (&handshake->lock){++++}-{4:4}, at: wg_noise_handshake_consume_initiation+0x5ac/0x860 drivers/net/wireguard/noise.c:632
3 locks held by kworker/u10:1/21928:
2 locks held by kworker/0:1/21939:
1 lock held by syz-executor/21944:
 #0: ffffffff906141a8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
 #0: ffffffff906141a8 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x30c/0x18b0 net/ipv4/devinet.c:978
1 lock held by syz-executor/21949:
 #0: ffffffff906141a8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
 #0: ffffffff906141a8 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x30c/0x18b0 net/ipv4/devinet.c:978
1 lock held by syz-executor/21956:
 #0: ffffffff906141a8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
 #0: ffffffff906141a8 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x30c/0x18b0 net/ipv4/devinet.c:978
1 lock held by syz-executor/21958:
 #0: ffffffff906141a8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
 #0: ffffffff906141a8 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x30c/0x18b0 net/ipv4/devinet.c:978
3 locks held by kworker/u10:2/21961:
3 locks held by kworker/u10:3/21962:
4 locks held by kworker/u10:4/21963:
6 locks held by kworker/u10:5/21964:
3 locks held by kworker/u10:6/21965:
3 locks held by kworker/0:4/21969:
 #0: ffff88813fe63148 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x1310/0x19a0 kernel/workqueue.c:3251
 #1: ffffc900045e7d08 (deferred_process_work){+.+.}-{0:0}, at: process_one_work+0x988/0x19a0 kernel/workqueue.c:3252
 #2: ffffffff906141a8 (rtnl_mutex){+.+.}-{4:4}, at: switchdev_deferred_process_work+0xe/0x20 net/switchdev/switchdev.c:104
4 locks held by kworker/u10:11/21970:
 #0: ffff888035815948 ((wq_completion)wg-kex-wg1#7){+.+.}-{0:0}, at: process_one_work+0x1310/0x19a0 kernel/workqueue.c:3251
 #1: ffffc900045d7d08 ((work_completion)(&peer->transmit_handshake_work)){+.+.}-{0:0}, at: process_one_work+0x988/0x19a0 kernel/workqueue.c:3252
 #2: ffff88805d99d348 (&wg->static_identity.lock){++++}-{4:4}, at: wg_noise_handshake_create_initiation+0xec/0x610 drivers/net/wireguard/noise.c:529
 #3: ffff88805c09c890 (&handshake->lock){++++}-{4:4}, at: wg_noise_handshake_create_initiation+0x100/0x610 drivers/net/wireguard/noise.c:530
3 locks held by kworker/u10:12/21974:
 #0: ffff888033241148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x1310/0x19a0 kernel/workqueue.c:3251
 #1: ffffc90004597d08 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_one_work+0x988/0x19a0 kernel/workqueue.c:3252
 #2: ffffffff906141a8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
 #2: ffffffff906141a8 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_verify_work+0x12/0x30 net/ipv6/addrconf.c:4738
3 locks held by kworker/u10:14/21976:
4 locks held by kworker/u10:16/21978:
4 locks held by kworker/u10:17/21982:
3 locks held by kworker/u10:18/21983:
4 locks held by kworker/u10:20/21985:
1 lock held by syz-executor/21988:
 #0: ffffffff906141a8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
 #0: ffffffff906141a8 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x30c/0x18b0 net/ipv4/devinet.c:978
1 lock held by syz-executor/21991:
 #0: ffffffff906141a8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
 #0: ffffffff906141a8 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x30c/0x18b0 net/ipv4/devinet.c:978
3 locks held by kworker/u10:21/21994:
3 locks held by kworker/u10:22/21995:
3 locks held by kworker/u10:27/22002:
7 locks held by kworker/u10:29/22003:
4 locks held by kworker/u10:30/22004:
3 locks held by kworker/u10:31/22008:
4 locks held by kworker/0:10/22015:
4 locks held by kworker/0:11/22016:
 #0: ffff888059346548 ((wq_completion)wg-kex-wg0#20){+.+.}-{0:0}, at: process_one_work+0x1310/0x19a0 kernel/workqueue.c:3251
 #1: ffffc900038b7d08 ((work_completion)(&({ do { const void __seg_gs *__vpp_verify = (typeof((worker) + 0))((void *)0); (void)__vpp_verify; } while (0); ({ unsigned long __ptr; __asm__ ("" : "=r"(__ptr) : "0"((__typeof_unqual__(*((worker))) *)(( unsigned long)((worker))))); (typeof((__typeof_unqual__(*((worker))) *)(( unsigned long)((worker))))) (__ptr + (((__per_cpu_offset[(cpu)])))); }); })->work)){+.+.}-{0:0}, at: process_one_work+0x988/0x19a0 kernel/workqueue.c:3252
 #2: ffff88807a5c1348 (&wg->static_identity.lock){++++}-{4:4}, at: wg_noise_handshake_consume_initiation+0x1c2/0x860 drivers/net/wireguard/noise.c:598
 #3: ffff88803320a0f0 (&handshake->lock){++++}-{4:4}, at: wg_noise_handshake_consume_initiation+0x5ac/0x860 drivers/net/wireguard/noise.c:632
5 locks held by kworker/0:12/22017:
4 locks held by kworker/u10:32/22026:
4 locks held by kworker/u10:36/22028:
4 locks held by kworker/1:10/22029:
 #0: ffff888036923d48 ((wq_completion)wg-kex-wg0#8){+.+.}-{0:0}, at: process_one_work+0x1310/0x19a0 kernel/workqueue.c:3251
 #1: ffffc90003837d08 ((work_completion)(&({ do { const void __seg_gs *__vpp_verify = (typeof((worker) + 0))((void *)0); (void)__vpp_verify; } while (0); ({ unsigned long __ptr; __asm__ ("" : "=r"(__ptr) : "0"((__typeof_unqual__(*((worker))) *)(( unsigned long)((worker))))); (typeof((__typeof_unqual__(*((worker))) *)(( unsigned long)((worker))))) (__ptr + (((__per_cpu_offset[(cpu)])))); }); })->work)){+.+.}-{0:0}, at: process_one_work+0x988/0x19a0 kernel/workqueue.c:3252
 #2: ffff88805d9a1348 (&wg->static_identity.lock){++++}-{4:4}, at: wg_noise_handshake_consume_initiation+0x1c2/0x860 drivers/net/wireguard/noise.c:598
 #3: ffff88805c2bdc60 (&handshake->lock){++++}-{4:4}, at: wg_noise_handshake_consume_initiation+0x5ac/0x860 drivers/net/wireguard/noise.c:632
2 locks held by dhcpcd/22035:
 #0: ffff888050f4e260 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1709 [inline]
 #0: ffff888050f4e260 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x2c/0xf50 net/packet/af_packet.c:3197
 #1: ffffffff8e7f30f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x19e/0x3c0 kernel/rcu/tree_exp.h:343
1 lock held by dhcpcd/22036:
 #0: ffff88805a4e8260 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1709 [inline]
 #0: ffff88805a4e8260 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x2c/0xf50 net/packet/af_packet.c:3197
1 lock held by dhcpcd/22037:
 #0: ffff88807b770260 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1709 [inline]
 #0: ffff88807b770260 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x2c/0xf50 net/packet/af_packet.c:3197
1 lock held by dhcpcd/22039:
 #0: ffff88802b058260 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1709 [inline]
 #0: ffff88802b058260 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x2c/0xf50 net/packet/af_packet.c:3197

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

NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Tainted: G     U       L      syzkaller #0 PREEMPT(full) 
Tainted: [U]=USER, [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120
 nmi_cpu_backtrace.cold+0x12d/0x151 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x1d7/0x230 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:161 [inline]
 __sys_info lib/sys_info.c:157 [inline]
 sys_info+0x141/0x190 lib/sys_info.c:165
 check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline]
 watchdog+0xd25/0x1050 kernel/hung_task.c:515
 kthread+0x370/0x450 kernel/kthread.c:436
 ret_from_fork+0x754/0xd80 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 14788 Comm: kworker/u10:34 Tainted: G     U       L      syzkaller #0 PREEMPT(full) 
Tainted: [U]=USER, [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Workqueue: events_unbound cfg80211_wiphy_work
RIP: 0010:arch_irqs_disabled_flags arch/x86/include/asm/irqflags.h:146 [inline]
RIP: 0010:lock_acquire kernel/locking/lockdep.c:5869 [inline]
RIP: 0010:lock_acquire+0x19b/0x380 kernel/locking/lockdep.c:5825
Code: 00 00 85 d2 0f 85 98 00 00 00 9c 8f 04 24 fa 48 c7 c7 82 0f f7 8d e8 44 16 a9 09 45 89 e8 44 89 e1 89 da 65 ff 05 ad 48 29 12 <4c> 8b 14 24 44 89 f6 48 89 ef 41 81 e2 00 02 00 00 4c 89 14 24 4d
RSP: 0018:ffffc90000006a40 EFLAGS: 00000002
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000002
RDX: 0000000000000000 RSI: ffffffff8df70f82 RDI: ffffffff8c1b06a0
RBP: ffffffff8e7e74e0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000200 R11: 00000000000a01fb R12: 0000000000000002
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff88812434a000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f476b962e9c CR3: 000000000e598000 CR4: 00000000003526f0
Call Trace:
 <IRQ>
 rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
 rcu_read_lock include/linux/rcupdate.h:850 [inline]
 class_rcu_constructor include/linux/rcupdate.h:1193 [inline]
 unwind_next_frame+0xd1/0x1ea0 arch/x86/kernel/unwind_orc.c:495
 arch_stack_walk+0x94/0xf0 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
 kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
 kasan_save_track+0x14/0x30 mm/kasan/common.c:78
 kasan_save_free_info+0x3b/0x70 mm/kasan/generic.c:584
 poison_slab_object mm/kasan/common.c:253 [inline]
 __kasan_slab_free+0x5f/0x80 mm/kasan/common.c:285
 kasan_slab_free include/linux/kasan.h:235 [inline]
 slab_free_hook mm/slub.c:2685 [inline]
 slab_free mm/slub.c:6165 [inline]
 kmem_cache_free+0x124/0x6a0 mm/slub.c:6295
 __skb_ext_put+0x102/0x2f0 net/core/skbuff.c:7252
 skb_ext_reset include/linux/skbuff.h:5090 [inline]
 skb_ext_reset include/linux/skbuff.h:5087 [inline]
 skb_release_head_state+0x2c8/0x400 net/core/skbuff.c:1195
 skb_release_all net/core/skbuff.c:1201 [inline]
 __kfree_skb net/core/skbuff.c:1217 [inline]
 sk_skb_reason_drop+0xc4/0x1b0 net/core/skbuff.c:1255
 kfree_skb_reason include/linux/skbuff.h:1322 [inline]
 kfree_skb include/linux/skbuff.h:1331 [inline]
 ip6_mc_input+0x832/0xf50 net/ipv6/ip6_input.c:593
 dst_input include/net/dst.h:480 [inline]
 ip6_rcv_finish+0x294/0x300 net/ipv6/ip6_input.c:79
 ip_sabotage_in+0x21e/0x290 net/bridge/br_netfilter_hooks.c:990
 nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline]
 nf_hook_slow+0xbf/0x220 net/netfilter/core.c:623
 nf_hook.constprop.0+0x2a6/0x750 include/linux/netfilter.h:273
 NF_HOOK include/linux/netfilter.h:316 [inline]
 ipv6_rcv+0xa4/0x3d0 net/ipv6/ip6_input.c:311
 __netif_receive_skb_one_core+0x12d/0x1e0 net/core/dev.c:6164
 __netif_receive_skb+0x1f/0x120 net/core/dev.c:6277
 netif_receive_skb_internal net/core/dev.c:6363 [inline]
 netif_receive_skb+0x139/0x820 net/core/dev.c:6422
 NF_HOOK include/linux/netfilter.h:318 [inline]
 NF_HOOK include/linux/netfilter.h:312 [inline]
 br_pass_frame_up+0x346/0x490 net/bridge/br_input.c:70
 br_handle_frame_finish+0xa74/0x1f60 net/bridge/br_input.c:235
 br_nf_hook_thresh+0x30d/0x420 net/bridge/br_netfilter_hooks.c:1167
 br_nf_pre_routing_finish_ipv6+0x769/0xfb0 net/bridge/br_netfilter_ipv6.c:154
 NF_HOOK include/linux/netfilter.h:318 [inline]
 br_nf_pre_routing_ipv6+0x39c/0x8b0 net/bridge/br_netfilter_ipv6.c:184
 br_nf_pre_routing+0x90d/0x1550 net/bridge/br_netfilter_hooks.c:508
 nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline]
 nf_hook_bridge_pre net/bridge/br_input.c:291 [inline]
 br_handle_frame+0xcdd/0x1520 net/bridge/br_input.c:442
 __netif_receive_skb_core.constprop.0+0x6c5/0x3550 net/core/dev.c:6051
 __netif_receive_skb_one_core+0xb0/0x1e0 net/core/dev.c:6162
 __netif_receive_skb+0x1f/0x120 net/core/dev.c:6277
 process_backlog+0x37a/0x1580 net/core/dev.c:6628
 __napi_poll.constprop.0+0xaf/0x450 net/core/dev.c:7692
 napi_poll net/core/dev.c:7755 [inline]
 net_rx_action+0xa40/0xf20 net/core/dev.c:7912
 handle_softirqs+0x1eb/0x9e0 kernel/softirq.c:622
 do_softirq kernel/softirq.c:523 [inline]
 do_softirq+0xac/0xe0 kernel/softirq.c:510
 </IRQ>
 <TASK>
 __local_bh_enable_ip+0xf8/0x120 kernel/softirq.c:450
 spin_unlock_bh include/linux/spinlock.h:395 [inline]
 cfg80211_inform_single_bss_data+0x959/0x1e20 net/wireless/scan.c:2388
 cfg80211_inform_bss_data+0x237/0x3a00 net/wireless/scan.c:3226
 cfg80211_inform_bss_frame_data+0x247/0x790 net/wireless/scan.c:3317
 ieee80211_bss_info_update+0x310/0xab0 net/mac80211/scan.c:230
 ieee80211_rx_bss_info net/mac80211/ibss.c:1094 [inline]
 ieee80211_rx_mgmt_probe_beacon net/mac80211/ibss.c:1575 [inline]
 ieee80211_ibss_rx_queued_mgmt+0x1919/0x2f80 net/mac80211/ibss.c:1602
 ieee80211_iface_process_skb net/mac80211/iface.c:1748 [inline]
 ieee80211_iface_work+0xbff/0x13d0 net/mac80211/iface.c:1802
 cfg80211_wiphy_work+0x446/0x5c0 net/wireless/core.c:440
 process_one_work+0xa23/0x19a0 kernel/workqueue.c:3276
 process_scheduled_works kernel/workqueue.c:3359 [inline]
 worker_thread+0x5ef/0xe50 kernel/workqueue.c:3440
 kthread+0x370/0x450 kernel/kthread.c:436
 ret_from_fork+0x754/0xd80 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
net_ratelimit: 6252 callbacks suppressed
bridge0: received packet on veth0_to_bridge with own address as source address (addr:16:7c:ac:e4:46:ff, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:16:7c:ac:e4:46:ff, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:16:7c:ac:e4:46:ff, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:16:7c:ac:e4:46:ff, vlan:0)

Crashes (7):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/03/17 03:56 upstream 2d1373e4246d 0737c18f .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto INFO: task hung in caif_exit_net
2026/02/15 15:59 upstream ca4ee40bf13d 1e62d198 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto INFO: task hung in caif_exit_net
2025/12/12 16:32 upstream 187d0801404f d1b870e1 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto INFO: task hung in caif_exit_net
2025/12/10 07:35 upstream 3d99347a2e1a d1b870e1 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto INFO: task hung in caif_exit_net
2026/02/07 04:27 net ee9241524b46 f20fc9f9 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in caif_exit_net
2026/03/30 01:54 net-next 02d0e59e36e0 356bdfc9 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in caif_exit_net
2026/01/14 01:41 net-next c65182ef9df6 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in caif_exit_net
* Struck through repros no longer work on HEAD.