[v5.15] INFO: task hung in addrconf_dad_work
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syzbot
Jan 20, 2024, 3:09:26 AM1/20/24
to syzkaller...@googlegroups.com
Hello,
syzbot found the following issue on:
HEAD commit: ddcaf4999061 Linux 5.15.147
git tree: linux-5.15.y
console output: https://syzkaller.appspot.com/x/log.txt?x=13371143e80000
kernel config: https://syzkaller.appspot.com/x/.config?x=8c65db3d25098c3c
dashboard link: https://syzkaller.appspot.com/bug?extid=ccc611a0c79fb895b37f
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/fe87fb57528f/disk-ddcaf499.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/f64608a2759c/vmlinux-ddcaf499.xz
kernel image: https://storage.googleapis.com/syzbot-assets/84cae5bc6ed5/bzImage-ddcaf499.xz
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+ccc611...@syzkaller.appspotmail.com
INFO: task kworker/1:5:26544 blocked for more than 143 seconds.
Not tainted 5.15.147-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/1:5 state:D stack:24696 pid:26544 ppid: 2 flags:0x00004000
Workqueue: ipv6_addrconf addrconf_dad_work
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5030 [inline]
__schedule+0x12c4/0x45b0 kernel/sched/core.c:6376
schedule+0x11b/0x1f0 kernel/sched/core.c:6459
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6518
__mutex_lock_common+0xe34/0x25a0 kernel/locking/mutex.c:669
__mutex_lock kernel/locking/mutex.c:729 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
addrconf_dad_work+0xcc/0x1720 net/ipv6/addrconf.c:4096
process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310
worker_thread+0xaca/0x1280 kernel/workqueue.c:2457
kthread+0x3f6/0x4f0 kernel/kthread.c:319
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298
</TASK>
INFO: task kworker/1:9:26548 blocked for more than 144 seconds.
Not tainted 5.15.147-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/1:9 state:D stack:23616 pid:26548 ppid: 2 flags:0x00004000
Workqueue: events linkwatch_event
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5030 [inline]
__schedule+0x12c4/0x45b0 kernel/sched/core.c:6376
schedule+0x11b/0x1f0 kernel/sched/core.c:6459
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6518
__mutex_lock_common+0xe34/0x25a0 kernel/locking/mutex.c:669
__mutex_lock kernel/locking/mutex.c:729 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
linkwatch_event+0xa/0x50 net/core/link_watch.c:251
process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310
worker_thread+0xaca/0x1280 kernel/workqueue.c:2457
kthread+0x3f6/0x4f0 kernel/kthread.c:319
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298
</TASK>
INFO: task kworker/0:18:10426 blocked for more than 144 seconds.
Not tainted 5.15.147-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/0:18 state:D stack:25176 pid:10426 ppid: 2 flags:0x00004000
Workqueue: ipv6_addrconf addrconf_dad_work
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5030 [inline]
__schedule+0x12c4/0x45b0 kernel/sched/core.c:6376
schedule+0x11b/0x1f0 kernel/sched/core.c:6459
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6518
__mutex_lock_common+0xe34/0x25a0 kernel/locking/mutex.c:669
__mutex_lock kernel/locking/mutex.c:729 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
addrconf_dad_work+0xcc/0x1720 net/ipv6/addrconf.c:4096
process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310
worker_thread+0xaca/0x1280 kernel/workqueue.c:2457
kthread+0x3f6/0x4f0 kernel/kthread.c:319
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298
</TASK>
INFO: task kworker/0:13:29487 blocked for more than 145 seconds.
Not tainted 5.15.147-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/0:13 state:D stack:25592 pid:29487 ppid: 2 flags:0x00004000
Workqueue: events switchdev_deferred_process_work
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5030 [inline]
__schedule+0x12c4/0x45b0 kernel/sched/core.c:6376
schedule+0x11b/0x1f0 kernel/sched/core.c:6459
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6518
__mutex_lock_common+0xe34/0x25a0 kernel/locking/mutex.c:669
__mutex_lock kernel/locking/mutex.c:729 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
switchdev_deferred_process_work+0xa/0x20 net/switchdev/switchdev.c:74
process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310
worker_thread+0xaca/0x1280 kernel/workqueue.c:2457
kthread+0x3f6/0x4f0 kernel/kthread.c:319
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298
</TASK>
INFO: task kworker/0:14:29488 blocked for more than 145 seconds.
Not tainted 5.15.147-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/0:14 state:D stack:25592 pid:29488 ppid: 2 flags:0x00004000
Workqueue: events nsim_dev_trap_report_work
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5030 [inline]
__schedule+0x12c4/0x45b0 kernel/sched/core.c:6376
schedule+0x11b/0x1f0 kernel/sched/core.c:6459
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6518
__mutex_lock_common+0xe34/0x25a0 kernel/locking/mutex.c:669
__mutex_lock kernel/locking/mutex.c:729 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
nsim_dev_trap_report_work+0x56/0xab0 drivers/net/netdevsim/dev.c:757
process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310
worker_thread+0xaca/0x1280 kernel/workqueue.c:2457
kthread+0x3f6/0x4f0 kernel/kthread.c:319
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298
</TASK>
INFO: task syz-executor.5:31896 blocked for more than 146 seconds.
Not tainted 5.15.147-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.5 state:D stack:22880 pid:31896 ppid: 31626 flags:0x00004006
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5030 [inline]
__schedule+0x12c4/0x45b0 kernel/sched/core.c:6376
schedule+0x11b/0x1f0 kernel/sched/core.c:6459
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6518
__mutex_lock_common+0xe34/0x25a0 kernel/locking/mutex.c:669
__mutex_lock kernel/locking/mutex.c:729 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
netdev_wait_allrefs net/core/dev.c:10524 [inline]
netdev_run_todo+0x610/0xc40 net/core/dev.c:10637
nsim_destroy+0xac/0x140 drivers/net/netdevsim/netdev.c:387
__nsim_dev_port_del+0x153/0x1b0 drivers/net/netdevsim/dev.c:1349
nsim_dev_port_del_all drivers/net/netdevsim/dev.c:1362 [inline]
nsim_dev_reload_destroy+0x15e/0x240 drivers/net/netdevsim/dev.c:1561
nsim_dev_reload_down+0x103/0x160 drivers/net/netdevsim/dev.c:883
devlink_reload+0x247/0x750 net/core/devlink.c:3963
devlink_nl_cmd_reload+0xbe2/0xe70 net/core/devlink.c:4084
genl_family_rcv_msg_doit net/netlink/genetlink.c:731 [inline]
genl_family_rcv_msg net/netlink/genetlink.c:775 [inline]
genl_rcv_msg+0xfbd/0x14a0 net/netlink/genetlink.c:792
netlink_rcv_skb+0x1cf/0x410 net/netlink/af_netlink.c:2505
genl_rcv+0x24/0x40 net/netlink/genetlink.c:803
netlink_unicast_kernel net/netlink/af_netlink.c:1330 [inline]
netlink_unicast+0x7b6/0x980 net/netlink/af_netlink.c:1356
netlink_sendmsg+0xa30/0xd60 net/netlink/af_netlink.c:1924
sock_sendmsg_nosec net/socket.c:704 [inline]
__sock_sendmsg net/socket.c:716 [inline]
____sys_sendmsg+0x59e/0x8f0 net/socket.c:2431
___sys_sendmsg+0x252/0x2e0 net/socket.c:2485
__sys_sendmsg net/socket.c:2514 [inline]
__do_sys_sendmsg net/socket.c:2523 [inline]
__se_sys_sendmsg+0x19a/0x260 net/socket.c:2521
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x61/0xcb
RIP: 0033:0x7fa388112da9
RSP: 002b:00007fa3866940c8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007fa388241f80 RCX: 00007fa388112da9
RDX: 0000000000000000 RSI: 0000000020000400 RDI: 0000000000000005
RBP: 00007fa38815f47a R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007fa388241f80 R15: 00007fffefcaba68
</TASK>
INFO: task syz-executor.5:31901 blocked for more than 148 seconds.
Not tainted 5.15.147-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.5 state:D stack:27768 pid:31901 ppid: 31626 flags:0x00004006
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5030 [inline]
__schedule+0x12c4/0x45b0 kernel/sched/core.c:6376
schedule+0x11b/0x1f0 kernel/sched/core.c:6459
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6518
__mutex_lock_common+0xe34/0x25a0 kernel/locking/mutex.c:669
__mutex_lock kernel/locking/mutex.c:729 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
genl_lock net/netlink/genetlink.c:33 [inline]
genl_rcv_msg+0x124/0x14a0 net/netlink/genetlink.c:790
netlink_rcv_skb+0x1cf/0x410 net/netlink/af_netlink.c:2505
genl_rcv+0x24/0x40 net/netlink/genetlink.c:803
netlink_unicast_kernel net/netlink/af_netlink.c:1330 [inline]
netlink_unicast+0x7b6/0x980 net/netlink/af_netlink.c:1356
netlink_sendmsg+0xa30/0xd60 net/netlink/af_netlink.c:1924
sock_sendmsg_nosec net/socket.c:704 [inline]
__sock_sendmsg net/socket.c:716 [inline]
__sys_sendto+0x564/0x720 net/socket.c:2058
__do_sys_sendto net/socket.c:2070 [inline]
__se_sys_sendto net/socket.c:2066 [inline]
__x64_sys_sendto+0xda/0xf0 net/socket.c:2066
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x61/0xcb
RIP: 0033:0x7fa388114a9c
RSP: 002b:00007fa3865edf60 EFLAGS: 00000293 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007fa3865ee050 RCX: 00007fa388114a9c
RDX: 000000000000001c RSI: 00007fa3865ee0a0 RDI: 0000000000000009
RBP: 0000000000000000 R08: 00007fa3865edfb4 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000009
R13: 00007fa3865ee008 R14: 00007fa3865ee0a0 R15: 0000000000000000
</TASK>
Showing all locks held in the system:
1 lock held by khungtaskd/27:
#0: ffffffff8c91f220 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
2 locks held by kworker/u4:1/144:
2 locks held by getty/3264:
#0: ffff88802338b098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
#1: ffffc90002bab2e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6af/0x1db0 drivers/tty/n_tty.c:2158
3 locks held by kworker/1:5/26544:
#0: ffff88814a544538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283
#1: ffffc9000ad0fd20 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285
#2: ffffffff8d9da3c8 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xcc/0x1720 net/ipv6/addrconf.c:4096
3 locks held by kworker/1:9/26548:
#0: ffff888011c70d38 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283
#1: ffffc9000ad4fd20 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285
#2: ffffffff8d9da3c8 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xa/0x50 net/core/link_watch.c:251
3 locks held by kworker/0:18/10426:
#0: ffff88814a544538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283
#1: ffffc900045bfd20 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285
#2: ffffffff8d9da3c8 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xcc/0x1720 net/ipv6/addrconf.c:4096
5 locks held by kworker/u4:3/10711:
#0: ffff888011dcd138 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283
#1: ffffc9000958fd20 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285
#2: ffffffff8d9ce810 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0xf1/0xb60 net/core/net_namespace.c:558
#3: ffffffff8d9da3c8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock_unregistering net/core/dev.c:11576 [inline]
#3: ffffffff8d9da3c8 (rtnl_mutex){+.+.}-{3:3}, at: default_device_exit_batch+0x1ac/0x3f0 net/core/dev.c:11614
#4: ffffffff8c9237e8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:290 [inline]
#4: ffffffff8c9237e8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x280/0x740 kernel/rcu/tree_exp.h:845
3 locks held by kworker/1:1/23264:
#0: ffff888011c71d38 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283
#1: ffffc900114a7d20 ((reg_check_chans).work){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285
#2: ffffffff8d9da3c8 (rtnl_mutex){+.+.}-{3:3}, at: reg_check_chans_work+0x7f/0xb70 net/wireless/reg.c:2436
2 locks held by kworker/1:2/24033:
#0: ffff888011c72538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283
#1: ffffc900050ffd20 ((work_completion)(&rew.rew_work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285
3 locks held by kworker/0:13/29487:
#0: ffff888011c70d38 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283
#1: ffffc9000b60fd20 (deferred_process_work){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285
#2: ffffffff8d9da3c8 (rtnl_mutex){+.+.}-{3:3}, at: switchdev_deferred_process_work+0xa/0x20 net/switchdev/switchdev.c:74
3 locks held by kworker/0:14/29488:
#0: ffff888011c70d38 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283
#1: ffffc9000b61fd20 ((work_completion)(&(&nsim_dev->trap_data->trap_report_dw)->work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285
#2: ffff888178130400 (&nsim_dev->port_list_lock){+.+.}-{3:3}, at: nsim_dev_trap_report_work+0x56/0xab0 drivers/net/netdevsim/dev.c:757
6 locks held by syz-executor.5/31896:
#0: ffffffff8da39c90 (cb_lock){++++}-{3:3}, at: genl_rcv+0x15/0x40 net/netlink/genetlink.c:802
#1: ffffffff8da39b48 (genl_mutex){+.+.}-{3:3}, at: genl_lock net/netlink/genetlink.c:33 [inline]
#1: ffffffff8da39b48 (genl_mutex){+.+.}-{3:3}, at: genl_rcv_msg+0x124/0x14a0 net/netlink/genetlink.c:790
#2: ffffffff8d9ff9e8 (devlink_mutex){+.+.}-{3:3}, at: devlink_nl_pre_doit+0x31/0xa90 net/core/devlink.c:502
#3: ffff888178131658 (&nsim_bus_dev->nsim_bus_reload_lock){+.+.}-{3:3}, at: nsim_dev_reload_down+0x58/0x160 drivers/net/netdevsim/dev.c:870
#4: ffff888178130400 (&nsim_dev->port_list_lock){+.+.}-{3:3}, at: nsim_dev_port_del_all drivers/net/netdevsim/dev.c:1359 [inline]
#4: ffff888178130400 (&nsim_dev->port_list_lock){+.+.}-{3:3}, at: nsim_dev_reload_destroy+0x118/0x240 drivers/net/netdevsim/dev.c:1561
#5: ffffffff8d9da3c8 (rtnl_mutex){+.+.}-{3:3}, at: netdev_wait_allrefs net/core/dev.c:10524 [inline]
#5: ffffffff8d9da3c8 (rtnl_mutex){+.+.}-{3:3}, at: netdev_run_todo+0x610/0xc40 net/core/dev.c:10637
2 locks held by syz-executor.5/31901:
#0: ffffffff8da39c90 (cb_lock){++++}-{3:3}, at: genl_rcv+0x15/0x40 net/netlink/genetlink.c:802
#1: ffffffff8da39b48 (genl_mutex){+.+.}-{3:3}, at: genl_lock net/netlink/genetlink.c:33 [inline]
#1: ffffffff8da39b48 (genl_mutex){+.+.}-{3:3}, at: genl_rcv_msg+0x124/0x14a0 net/netlink/genetlink.c:790
1 lock held by syz-executor.4/31914:
#0: ffffffff8d9da3c8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline]
#0: ffffffff8d9da3c8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x94c/0xee0 net/core/rtnetlink.c:5627
2 locks held by syz-executor.1/31995:
#0: ffffffff8da39c90 (cb_lock){++++}-{3:3}, at: genl_rcv+0x15/0x40 net/netlink/genetlink.c:802
#1: ffffffff8da39b48 (genl_mutex){+.+.}-{3:3}, at: genl_lock net/netlink/genetlink.c:33 [inline]
#1: ffffffff8da39b48 (genl_mutex){+.+.}-{3:3}, at: genl_rcv_msg+0x124/0x14a0 net/netlink/genetlink.c:790
2 locks held by syz-executor.1/31997:
#0: ffffffff8da39c90 (cb_lock){++++}-{3:3}, at: genl_rcv+0x15/0x40 net/netlink/genetlink.c:802
#1: ffffffff8da39b48 (genl_mutex){+.+.}-{3:3}, at: genl_lock net/netlink/genetlink.c:33 [inline]
#1: ffffffff8da39b48 (genl_mutex){+.+.}-{3:3}, at: genl_rcv_msg+0x124/0x14a0 net/netlink/genetlink.c:790
2 locks held by syz-executor.1/31999:
#0: ffffffff8da39c90 (cb_lock){++++}-{3:3}, at: genl_rcv+0x15/0x40 net/netlink/genetlink.c:802
#1: ffffffff8da39b48 (genl_mutex){+.+.}-{3:3}, at: genl_lock net/netlink/genetlink.c:33 [inline]
#1: ffffffff8da39b48 (genl_mutex){+.+.}-{3:3}, at: genl_rcv_msg+0x124/0x14a0 net/netlink/genetlink.c:790
1 lock held by syz-executor.2/31996:
#0: ffffffff8d9da3c8 (rtnl_mutex){+.+.}-{3:3}, at: dev_ioctl+0x598/0xf60 net/core/dev_ioctl.c:611
1 lock held by syz-executor.5/32016:
#0: ffffffff8d9da3c8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline]
#0: ffffffff8d9da3c8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x94c/0xee0 net/core/rtnetlink.c:5627
1 lock held by syz-executor.2/32086:
#0: ffffffff8d9da3c8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline]
#0: ffffffff8d9da3c8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x94c/0xee0 net/core/rtnetlink.c:5627
1 lock held by syz-executor.1/32092:
#0: ffffffff8d9da3c8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline]
#0: ffffffff8d9da3c8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x94c/0xee0 net/core/rtnetlink.c:5627
1 lock held by syz-executor.4/32099:
#0: ffffffff8d9da3c8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline]
#0: ffffffff8d9da3c8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x94c/0xee0 net/core/rtnetlink.c:5627
=============================================
NMI backtrace for cpu 0
CPU: 0 PID: 27 Comm: khungtaskd Not tainted 5.15.147-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
nmi_cpu_backtrace+0x46a/0x4a0 lib/nmi_backtrace.c:111
nmi_trigger_cpumask_backtrace+0x181/0x2a0 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:210 [inline]
watchdog+0xe72/0xeb0 kernel/hung_task.c:295
kthread+0x3f6/0x4f0 kernel/kthread.c:319
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298
</TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 20 Comm: ksoftirqd/1 Not tainted 5.15.147-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023
RIP: 0010:variable_test_bit arch/x86/include/asm/bitops.h:219 [inline]
RIP: 0010:test_bit include/asm-generic/bitops/instrumented-non-atomic.h:135 [inline]
RIP: 0010:cpumask_test_cpu include/linux/cpumask.h:344 [inline]
RIP: 0010:cpu_online include/linux/cpumask.h:895 [inline]
RIP: 0010:trace_timer_expire_exit include/trace/events/timer.h:125 [inline]
RIP: 0010:call_timer_fn+0x1ce/0x560 kernel/time/timer.c:1422
Code: 8d be 08 00 00 00 e8 61 f0 5a 00 89 d8 31 db 48 0f a3 05 3d ab 74 0c 41 0f 92 c7 0f 92 c3 bf 02 00 00 00 89 de e8 62 3e 11 00 <31> ff 89 de e8 59 3e 11 00 45 84 ff 74 15 e8 bf f9 fb ff 84 c0 48
RSP: 0018:ffffc90000da7a40 EFLAGS: 00000046
RAX: 0000000000000100 RBX: 0000000000000001 RCX: ffffffff816ef11f
RDX: ffff888012970000 RSI: 0000000000000001 RDI: 0000000000000002
RBP: ffffc90000da7b30 R08: ffffffff816ef13e R09: fffffbfff1bc738e
R10: 0000000000000000 R11: dffffc0000000001 R12: ffff8881517497a8
R13: 1ffff920001b4f4c R14: 0000000000000100 R15: 0000000100027001
FS: 0000000000000000(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffc371f8dbc CR3: 000000002393b000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<NMI>
</NMI>
<TASK>
expire_timers kernel/time/timer.c:1461 [inline]
__run_timers+0x6a8/0x890 kernel/time/timer.c:1737
run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1750
__do_softirq+0x3b3/0x93a kernel/softirq.c:558
run_ksoftirqd+0xc1/0x120 kernel/softirq.c:921
smpboot_thread_fn+0x51b/0x9d0 kernel/smpboot.c:164
kthread+0x3f6/0x4f0 kernel/kthread.c:319
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298
</TASK>
---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzk...@googlegroups.com.
syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
If the report is already addressed, let syzbot know by replying with:
#syz fix: exact-commit-title
If you want to overwrite report's subsystems, reply with:
#syz set subsystems: new-subsystem
(See the list of subsystem names on the web dashboard)
If the report is a duplicate of another one, reply with:
#syz dup: exact-subject-of-another-report
If you want to undo deduplication, reply with:
#syz undup
syzbot found the following issue on:
HEAD commit: ddcaf4999061 Linux 5.15.147
git tree: linux-5.15.y
console output: https://syzkaller.appspot.com/x/log.txt?x=13371143e80000
kernel config: https://syzkaller.appspot.com/x/.config?x=8c65db3d25098c3c
dashboard link: https://syzkaller.appspot.com/bug?extid=ccc611a0c79fb895b37f
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/fe87fb57528f/disk-ddcaf499.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/f64608a2759c/vmlinux-ddcaf499.xz
kernel image: https://storage.googleapis.com/syzbot-assets/84cae5bc6ed5/bzImage-ddcaf499.xz
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+ccc611...@syzkaller.appspotmail.com
INFO: task kworker/1:5:26544 blocked for more than 143 seconds.
Not tainted 5.15.147-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/1:5 state:D stack:24696 pid:26544 ppid: 2 flags:0x00004000
Workqueue: ipv6_addrconf addrconf_dad_work
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5030 [inline]
__schedule+0x12c4/0x45b0 kernel/sched/core.c:6376
schedule+0x11b/0x1f0 kernel/sched/core.c:6459
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6518
__mutex_lock_common+0xe34/0x25a0 kernel/locking/mutex.c:669
__mutex_lock kernel/locking/mutex.c:729 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
addrconf_dad_work+0xcc/0x1720 net/ipv6/addrconf.c:4096
process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310
worker_thread+0xaca/0x1280 kernel/workqueue.c:2457
kthread+0x3f6/0x4f0 kernel/kthread.c:319
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298
</TASK>
INFO: task kworker/1:9:26548 blocked for more than 144 seconds.
Not tainted 5.15.147-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/1:9 state:D stack:23616 pid:26548 ppid: 2 flags:0x00004000
Workqueue: events linkwatch_event
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5030 [inline]
__schedule+0x12c4/0x45b0 kernel/sched/core.c:6376
schedule+0x11b/0x1f0 kernel/sched/core.c:6459
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6518
__mutex_lock_common+0xe34/0x25a0 kernel/locking/mutex.c:669
__mutex_lock kernel/locking/mutex.c:729 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
linkwatch_event+0xa/0x50 net/core/link_watch.c:251
process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310
worker_thread+0xaca/0x1280 kernel/workqueue.c:2457
kthread+0x3f6/0x4f0 kernel/kthread.c:319
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298
</TASK>
INFO: task kworker/0:18:10426 blocked for more than 144 seconds.
Not tainted 5.15.147-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/0:18 state:D stack:25176 pid:10426 ppid: 2 flags:0x00004000
Workqueue: ipv6_addrconf addrconf_dad_work
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5030 [inline]
__schedule+0x12c4/0x45b0 kernel/sched/core.c:6376
schedule+0x11b/0x1f0 kernel/sched/core.c:6459
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6518
__mutex_lock_common+0xe34/0x25a0 kernel/locking/mutex.c:669
__mutex_lock kernel/locking/mutex.c:729 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
addrconf_dad_work+0xcc/0x1720 net/ipv6/addrconf.c:4096
process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310
worker_thread+0xaca/0x1280 kernel/workqueue.c:2457
kthread+0x3f6/0x4f0 kernel/kthread.c:319
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298
</TASK>
INFO: task kworker/0:13:29487 blocked for more than 145 seconds.
Not tainted 5.15.147-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/0:13 state:D stack:25592 pid:29487 ppid: 2 flags:0x00004000
Workqueue: events switchdev_deferred_process_work
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5030 [inline]
__schedule+0x12c4/0x45b0 kernel/sched/core.c:6376
schedule+0x11b/0x1f0 kernel/sched/core.c:6459
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6518
__mutex_lock_common+0xe34/0x25a0 kernel/locking/mutex.c:669
__mutex_lock kernel/locking/mutex.c:729 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
switchdev_deferred_process_work+0xa/0x20 net/switchdev/switchdev.c:74
process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310
worker_thread+0xaca/0x1280 kernel/workqueue.c:2457
kthread+0x3f6/0x4f0 kernel/kthread.c:319
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298
</TASK>
INFO: task kworker/0:14:29488 blocked for more than 145 seconds.
Not tainted 5.15.147-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/0:14 state:D stack:25592 pid:29488 ppid: 2 flags:0x00004000
Workqueue: events nsim_dev_trap_report_work
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5030 [inline]
__schedule+0x12c4/0x45b0 kernel/sched/core.c:6376
schedule+0x11b/0x1f0 kernel/sched/core.c:6459
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6518
__mutex_lock_common+0xe34/0x25a0 kernel/locking/mutex.c:669
__mutex_lock kernel/locking/mutex.c:729 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
nsim_dev_trap_report_work+0x56/0xab0 drivers/net/netdevsim/dev.c:757
process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310
worker_thread+0xaca/0x1280 kernel/workqueue.c:2457
kthread+0x3f6/0x4f0 kernel/kthread.c:319
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298
</TASK>
INFO: task syz-executor.5:31896 blocked for more than 146 seconds.
Not tainted 5.15.147-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.5 state:D stack:22880 pid:31896 ppid: 31626 flags:0x00004006
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5030 [inline]
__schedule+0x12c4/0x45b0 kernel/sched/core.c:6376
schedule+0x11b/0x1f0 kernel/sched/core.c:6459
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6518
__mutex_lock_common+0xe34/0x25a0 kernel/locking/mutex.c:669
__mutex_lock kernel/locking/mutex.c:729 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
netdev_wait_allrefs net/core/dev.c:10524 [inline]
netdev_run_todo+0x610/0xc40 net/core/dev.c:10637
nsim_destroy+0xac/0x140 drivers/net/netdevsim/netdev.c:387
__nsim_dev_port_del+0x153/0x1b0 drivers/net/netdevsim/dev.c:1349
nsim_dev_port_del_all drivers/net/netdevsim/dev.c:1362 [inline]
nsim_dev_reload_destroy+0x15e/0x240 drivers/net/netdevsim/dev.c:1561
nsim_dev_reload_down+0x103/0x160 drivers/net/netdevsim/dev.c:883
devlink_reload+0x247/0x750 net/core/devlink.c:3963
devlink_nl_cmd_reload+0xbe2/0xe70 net/core/devlink.c:4084
genl_family_rcv_msg_doit net/netlink/genetlink.c:731 [inline]
genl_family_rcv_msg net/netlink/genetlink.c:775 [inline]
genl_rcv_msg+0xfbd/0x14a0 net/netlink/genetlink.c:792
netlink_rcv_skb+0x1cf/0x410 net/netlink/af_netlink.c:2505
genl_rcv+0x24/0x40 net/netlink/genetlink.c:803
netlink_unicast_kernel net/netlink/af_netlink.c:1330 [inline]
netlink_unicast+0x7b6/0x980 net/netlink/af_netlink.c:1356
netlink_sendmsg+0xa30/0xd60 net/netlink/af_netlink.c:1924
sock_sendmsg_nosec net/socket.c:704 [inline]
__sock_sendmsg net/socket.c:716 [inline]
____sys_sendmsg+0x59e/0x8f0 net/socket.c:2431
___sys_sendmsg+0x252/0x2e0 net/socket.c:2485
__sys_sendmsg net/socket.c:2514 [inline]
__do_sys_sendmsg net/socket.c:2523 [inline]
__se_sys_sendmsg+0x19a/0x260 net/socket.c:2521
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x61/0xcb
RIP: 0033:0x7fa388112da9
RSP: 002b:00007fa3866940c8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007fa388241f80 RCX: 00007fa388112da9
RDX: 0000000000000000 RSI: 0000000020000400 RDI: 0000000000000005
RBP: 00007fa38815f47a R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007fa388241f80 R15: 00007fffefcaba68
</TASK>
INFO: task syz-executor.5:31901 blocked for more than 148 seconds.
Not tainted 5.15.147-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.5 state:D stack:27768 pid:31901 ppid: 31626 flags:0x00004006
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5030 [inline]
__schedule+0x12c4/0x45b0 kernel/sched/core.c:6376
schedule+0x11b/0x1f0 kernel/sched/core.c:6459
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6518
__mutex_lock_common+0xe34/0x25a0 kernel/locking/mutex.c:669
__mutex_lock kernel/locking/mutex.c:729 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
genl_lock net/netlink/genetlink.c:33 [inline]
genl_rcv_msg+0x124/0x14a0 net/netlink/genetlink.c:790
netlink_rcv_skb+0x1cf/0x410 net/netlink/af_netlink.c:2505
genl_rcv+0x24/0x40 net/netlink/genetlink.c:803
netlink_unicast_kernel net/netlink/af_netlink.c:1330 [inline]
netlink_unicast+0x7b6/0x980 net/netlink/af_netlink.c:1356
netlink_sendmsg+0xa30/0xd60 net/netlink/af_netlink.c:1924
sock_sendmsg_nosec net/socket.c:704 [inline]
__sock_sendmsg net/socket.c:716 [inline]
__sys_sendto+0x564/0x720 net/socket.c:2058
__do_sys_sendto net/socket.c:2070 [inline]
__se_sys_sendto net/socket.c:2066 [inline]
__x64_sys_sendto+0xda/0xf0 net/socket.c:2066
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x61/0xcb
RIP: 0033:0x7fa388114a9c
RSP: 002b:00007fa3865edf60 EFLAGS: 00000293 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007fa3865ee050 RCX: 00007fa388114a9c
RDX: 000000000000001c RSI: 00007fa3865ee0a0 RDI: 0000000000000009
RBP: 0000000000000000 R08: 00007fa3865edfb4 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000009
R13: 00007fa3865ee008 R14: 00007fa3865ee0a0 R15: 0000000000000000
</TASK>
Showing all locks held in the system:
1 lock held by khungtaskd/27:
#0: ffffffff8c91f220 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
2 locks held by kworker/u4:1/144:
2 locks held by getty/3264:
#0: ffff88802338b098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
#1: ffffc90002bab2e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6af/0x1db0 drivers/tty/n_tty.c:2158
3 locks held by kworker/1:5/26544:
#0: ffff88814a544538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283
#1: ffffc9000ad0fd20 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285
#2: ffffffff8d9da3c8 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xcc/0x1720 net/ipv6/addrconf.c:4096
3 locks held by kworker/1:9/26548:
#0: ffff888011c70d38 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283
#1: ffffc9000ad4fd20 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285
#2: ffffffff8d9da3c8 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xa/0x50 net/core/link_watch.c:251
3 locks held by kworker/0:18/10426:
#0: ffff88814a544538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283
#1: ffffc900045bfd20 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285
#2: ffffffff8d9da3c8 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xcc/0x1720 net/ipv6/addrconf.c:4096
5 locks held by kworker/u4:3/10711:
#0: ffff888011dcd138 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283
#1: ffffc9000958fd20 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285
#2: ffffffff8d9ce810 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0xf1/0xb60 net/core/net_namespace.c:558
#3: ffffffff8d9da3c8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock_unregistering net/core/dev.c:11576 [inline]
#3: ffffffff8d9da3c8 (rtnl_mutex){+.+.}-{3:3}, at: default_device_exit_batch+0x1ac/0x3f0 net/core/dev.c:11614
#4: ffffffff8c9237e8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:290 [inline]
#4: ffffffff8c9237e8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x280/0x740 kernel/rcu/tree_exp.h:845
3 locks held by kworker/1:1/23264:
#0: ffff888011c71d38 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283
#1: ffffc900114a7d20 ((reg_check_chans).work){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285
#2: ffffffff8d9da3c8 (rtnl_mutex){+.+.}-{3:3}, at: reg_check_chans_work+0x7f/0xb70 net/wireless/reg.c:2436
2 locks held by kworker/1:2/24033:
#0: ffff888011c72538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283
#1: ffffc900050ffd20 ((work_completion)(&rew.rew_work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285
3 locks held by kworker/0:13/29487:
#0: ffff888011c70d38 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283
#1: ffffc9000b60fd20 (deferred_process_work){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285
#2: ffffffff8d9da3c8 (rtnl_mutex){+.+.}-{3:3}, at: switchdev_deferred_process_work+0xa/0x20 net/switchdev/switchdev.c:74
3 locks held by kworker/0:14/29488:
#0: ffff888011c70d38 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283
#1: ffffc9000b61fd20 ((work_completion)(&(&nsim_dev->trap_data->trap_report_dw)->work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285
#2: ffff888178130400 (&nsim_dev->port_list_lock){+.+.}-{3:3}, at: nsim_dev_trap_report_work+0x56/0xab0 drivers/net/netdevsim/dev.c:757
6 locks held by syz-executor.5/31896:
#0: ffffffff8da39c90 (cb_lock){++++}-{3:3}, at: genl_rcv+0x15/0x40 net/netlink/genetlink.c:802
#1: ffffffff8da39b48 (genl_mutex){+.+.}-{3:3}, at: genl_lock net/netlink/genetlink.c:33 [inline]
#1: ffffffff8da39b48 (genl_mutex){+.+.}-{3:3}, at: genl_rcv_msg+0x124/0x14a0 net/netlink/genetlink.c:790
#2: ffffffff8d9ff9e8 (devlink_mutex){+.+.}-{3:3}, at: devlink_nl_pre_doit+0x31/0xa90 net/core/devlink.c:502
#3: ffff888178131658 (&nsim_bus_dev->nsim_bus_reload_lock){+.+.}-{3:3}, at: nsim_dev_reload_down+0x58/0x160 drivers/net/netdevsim/dev.c:870
#4: ffff888178130400 (&nsim_dev->port_list_lock){+.+.}-{3:3}, at: nsim_dev_port_del_all drivers/net/netdevsim/dev.c:1359 [inline]
#4: ffff888178130400 (&nsim_dev->port_list_lock){+.+.}-{3:3}, at: nsim_dev_reload_destroy+0x118/0x240 drivers/net/netdevsim/dev.c:1561
#5: ffffffff8d9da3c8 (rtnl_mutex){+.+.}-{3:3}, at: netdev_wait_allrefs net/core/dev.c:10524 [inline]
#5: ffffffff8d9da3c8 (rtnl_mutex){+.+.}-{3:3}, at: netdev_run_todo+0x610/0xc40 net/core/dev.c:10637
2 locks held by syz-executor.5/31901:
#0: ffffffff8da39c90 (cb_lock){++++}-{3:3}, at: genl_rcv+0x15/0x40 net/netlink/genetlink.c:802
#1: ffffffff8da39b48 (genl_mutex){+.+.}-{3:3}, at: genl_lock net/netlink/genetlink.c:33 [inline]
#1: ffffffff8da39b48 (genl_mutex){+.+.}-{3:3}, at: genl_rcv_msg+0x124/0x14a0 net/netlink/genetlink.c:790
1 lock held by syz-executor.4/31914:
#0: ffffffff8d9da3c8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline]
#0: ffffffff8d9da3c8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x94c/0xee0 net/core/rtnetlink.c:5627
2 locks held by syz-executor.1/31995:
#0: ffffffff8da39c90 (cb_lock){++++}-{3:3}, at: genl_rcv+0x15/0x40 net/netlink/genetlink.c:802
#1: ffffffff8da39b48 (genl_mutex){+.+.}-{3:3}, at: genl_lock net/netlink/genetlink.c:33 [inline]
#1: ffffffff8da39b48 (genl_mutex){+.+.}-{3:3}, at: genl_rcv_msg+0x124/0x14a0 net/netlink/genetlink.c:790
2 locks held by syz-executor.1/31997:
#0: ffffffff8da39c90 (cb_lock){++++}-{3:3}, at: genl_rcv+0x15/0x40 net/netlink/genetlink.c:802
#1: ffffffff8da39b48 (genl_mutex){+.+.}-{3:3}, at: genl_lock net/netlink/genetlink.c:33 [inline]
#1: ffffffff8da39b48 (genl_mutex){+.+.}-{3:3}, at: genl_rcv_msg+0x124/0x14a0 net/netlink/genetlink.c:790
2 locks held by syz-executor.1/31999:
#0: ffffffff8da39c90 (cb_lock){++++}-{3:3}, at: genl_rcv+0x15/0x40 net/netlink/genetlink.c:802
#1: ffffffff8da39b48 (genl_mutex){+.+.}-{3:3}, at: genl_lock net/netlink/genetlink.c:33 [inline]
#1: ffffffff8da39b48 (genl_mutex){+.+.}-{3:3}, at: genl_rcv_msg+0x124/0x14a0 net/netlink/genetlink.c:790
1 lock held by syz-executor.2/31996:
#0: ffffffff8d9da3c8 (rtnl_mutex){+.+.}-{3:3}, at: dev_ioctl+0x598/0xf60 net/core/dev_ioctl.c:611
1 lock held by syz-executor.5/32016:
#0: ffffffff8d9da3c8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline]
#0: ffffffff8d9da3c8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x94c/0xee0 net/core/rtnetlink.c:5627
1 lock held by syz-executor.2/32086:
#0: ffffffff8d9da3c8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline]
#0: ffffffff8d9da3c8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x94c/0xee0 net/core/rtnetlink.c:5627
1 lock held by syz-executor.1/32092:
#0: ffffffff8d9da3c8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline]
#0: ffffffff8d9da3c8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x94c/0xee0 net/core/rtnetlink.c:5627
1 lock held by syz-executor.4/32099:
#0: ffffffff8d9da3c8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline]
#0: ffffffff8d9da3c8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x94c/0xee0 net/core/rtnetlink.c:5627
=============================================
NMI backtrace for cpu 0
CPU: 0 PID: 27 Comm: khungtaskd Not tainted 5.15.147-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
nmi_cpu_backtrace+0x46a/0x4a0 lib/nmi_backtrace.c:111
nmi_trigger_cpumask_backtrace+0x181/0x2a0 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:210 [inline]
watchdog+0xe72/0xeb0 kernel/hung_task.c:295
kthread+0x3f6/0x4f0 kernel/kthread.c:319
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298
</TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 20 Comm: ksoftirqd/1 Not tainted 5.15.147-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023
RIP: 0010:variable_test_bit arch/x86/include/asm/bitops.h:219 [inline]
RIP: 0010:test_bit include/asm-generic/bitops/instrumented-non-atomic.h:135 [inline]
RIP: 0010:cpumask_test_cpu include/linux/cpumask.h:344 [inline]
RIP: 0010:cpu_online include/linux/cpumask.h:895 [inline]
RIP: 0010:trace_timer_expire_exit include/trace/events/timer.h:125 [inline]
RIP: 0010:call_timer_fn+0x1ce/0x560 kernel/time/timer.c:1422
Code: 8d be 08 00 00 00 e8 61 f0 5a 00 89 d8 31 db 48 0f a3 05 3d ab 74 0c 41 0f 92 c7 0f 92 c3 bf 02 00 00 00 89 de e8 62 3e 11 00 <31> ff 89 de e8 59 3e 11 00 45 84 ff 74 15 e8 bf f9 fb ff 84 c0 48
RSP: 0018:ffffc90000da7a40 EFLAGS: 00000046
RAX: 0000000000000100 RBX: 0000000000000001 RCX: ffffffff816ef11f
RDX: ffff888012970000 RSI: 0000000000000001 RDI: 0000000000000002
RBP: ffffc90000da7b30 R08: ffffffff816ef13e R09: fffffbfff1bc738e
R10: 0000000000000000 R11: dffffc0000000001 R12: ffff8881517497a8
R13: 1ffff920001b4f4c R14: 0000000000000100 R15: 0000000100027001
FS: 0000000000000000(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffc371f8dbc CR3: 000000002393b000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<NMI>
</NMI>
<TASK>
expire_timers kernel/time/timer.c:1461 [inline]
__run_timers+0x6a8/0x890 kernel/time/timer.c:1737
run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1750
__do_softirq+0x3b3/0x93a kernel/softirq.c:558
run_ksoftirqd+0xc1/0x120 kernel/softirq.c:921
smpboot_thread_fn+0x51b/0x9d0 kernel/smpboot.c:164
kthread+0x3f6/0x4f0 kernel/kthread.c:319
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298
</TASK>
---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzk...@googlegroups.com.
syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
If the report is already addressed, let syzbot know by replying with:
#syz fix: exact-commit-title
If you want to overwrite report's subsystems, reply with:
#syz set subsystems: new-subsystem
(See the list of subsystem names on the web dashboard)
If the report is a duplicate of another one, reply with:
#syz dup: exact-subject-of-another-report
If you want to undo deduplication, reply with:
#syz undup
syzbot
Oct 16, 2024, 12:25:36 PM10/16/24
to syzkaller...@googlegroups.com
syzbot has found a reproducer for the following issue on:
HEAD commit: 3a5928702e71 Linux 5.15.167
git tree: linux-5.15.y
console output: https://syzkaller.appspot.com/x/log.txt?x=10d57727980000
kernel config: https://syzkaller.appspot.com/x/.config?x=4d3fd5cca89ae935
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/ef5025f3d708/disk-3a592870.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/776fbdad3aa8/vmlinux-3a592870.xz
kernel image: https://storage.googleapis.com/syzbot-assets/79541db5bd16/bzImage-3a592870.xz
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+ccc611...@syzkaller.appspotmail.com
INFO: task kworker/0:3:3647 blocked for more than 145 seconds.
Not tainted 5.15.167-syzkaller #0
__schedule+0x12c4/0x45b0 kernel/sched/core.c:6373
schedule+0x11b/0x1f0 kernel/sched/core.c:6456
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6515
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
</TASK>
INFO: task syz-executor:3876 blocked for more than 146 seconds.
Not tainted 5.15.167-syzkaller #0
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5027 [inline]
__schedule+0x12c4/0x45b0 kernel/sched/core.c:6373
schedule+0x11b/0x1f0 kernel/sched/core.c:6456
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6515
rtnetlink_rcv_msg+0x94c/0xee0 net/core/rtnetlink.c:5615
netlink_rcv_skb+0x1cf/0x410 net/netlink/af_netlink.c:2503
netlink_unicast_kernel net/netlink/af_netlink.c:1326 [inline]
netlink_unicast+0x7b6/0x980 net/netlink/af_netlink.c:1352
netlink_sendmsg+0xa30/0xd60 net/netlink/af_netlink.c:1920
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7ff327043e8c
RSP: 002b:00007ffe8a45a570 EFLAGS: 00000293 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007ff327d28620 RCX: 00007ff327043e8c
RDX: 000000000000003c RSI: 00007ff327d28670 RDI: 0000000000000003
RBP: 0000000000000000 R08: 00007ffe8a45a5c4 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000003
R13: 0000000000000000 R14: 00007ff327d28670 R15: 0000000000000000
</TASK>
INFO: task syz-executor:3895 blocked for more than 149 seconds.
Not tainted 5.15.167-syzkaller #0
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5027 [inline]
__schedule+0x12c4/0x45b0 kernel/sched/core.c:6373
schedule+0x11b/0x1f0 kernel/sched/core.c:6456
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6515
rtnetlink_rcv_msg+0x94c/0xee0 net/core/rtnetlink.c:5615
netlink_rcv_skb+0x1cf/0x410 net/netlink/af_netlink.c:2503
netlink_unicast_kernel net/netlink/af_netlink.c:1326 [inline]
netlink_unicast+0x7b6/0x980 net/netlink/af_netlink.c:1352
netlink_sendmsg+0xa30/0xd60 net/netlink/af_netlink.c:1920
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fb0ff850e8c
RSP: 002b:00007ffce5bb8d90 EFLAGS: 00000293 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007fb100535620 RCX: 00007fb0ff850e8c
RDX: 0000000000000028 RSI: 00007fb100535670 RDI: 0000000000000003
RBP: 0000000000000000 R08: 00007ffce5bb8de4 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000003
R13: 0000000000000000 R14: 00007fb100535670 R15: 0000000000000000
</TASK>
INFO: task syz-executor:3897 blocked for more than 154 seconds.
Not tainted 5.15.167-syzkaller #0
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5027 [inline]
__schedule+0x12c4/0x45b0 kernel/sched/core.c:6373
schedule+0x11b/0x1f0 kernel/sched/core.c:6456
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6515
If you want syzbot to run the reproducer, reply with:
#syz test: git://repo/address.git branch-or-commit-hash
If you attach or paste a git patch, syzbot will apply it before testing.
HEAD commit: 3a5928702e71 Linux 5.15.167
git tree: linux-5.15.y
console output: https://syzkaller.appspot.com/x/log.txt?x=10d57727980000
kernel config: https://syzkaller.appspot.com/x/.config?x=4d3fd5cca89ae935
dashboard link: https://syzkaller.appspot.com/bug?extid=ccc611a0c79fb895b37f
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1504d030580000
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/ef5025f3d708/disk-3a592870.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/776fbdad3aa8/vmlinux-3a592870.xz
kernel image: https://storage.googleapis.com/syzbot-assets/79541db5bd16/bzImage-3a592870.xz
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+ccc611...@syzkaller.appspotmail.com
Not tainted 5.15.167-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/0:3 state:D stack:24544 pid: 3647 ppid: 2 flags:0x00004000
Workqueue: ipv6_addrconf addrconf_dad_work
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5027 [inline]
Call Trace:
<TASK>
__schedule+0x12c4/0x45b0 kernel/sched/core.c:6373
schedule+0x11b/0x1f0 kernel/sched/core.c:6456
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6515
__mutex_lock_common+0xe34/0x25a0 kernel/locking/mutex.c:669
__mutex_lock kernel/locking/mutex.c:729 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
addrconf_dad_work+0xcc/0x1720 net/ipv6/addrconf.c:4113
__mutex_lock kernel/locking/mutex.c:729 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310
worker_thread+0xaca/0x1280 kernel/workqueue.c:2457
kthread+0x3f6/0x4f0 kernel/kthread.c:334
worker_thread+0xaca/0x1280 kernel/workqueue.c:2457
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
</TASK>
INFO: task syz-executor:3876 blocked for more than 146 seconds.
Not tainted 5.15.167-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor state:D stack:21432 pid: 3876 ppid: 1 flags:0x00004004
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5027 [inline]
__schedule+0x12c4/0x45b0 kernel/sched/core.c:6373
schedule+0x11b/0x1f0 kernel/sched/core.c:6456
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6515
__mutex_lock_common+0xe34/0x25a0 kernel/locking/mutex.c:669
__mutex_lock kernel/locking/mutex.c:729 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
rtnl_lock net/core/rtnetlink.c:72 [inline]
__mutex_lock kernel/locking/mutex.c:729 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
rtnetlink_rcv_msg+0x94c/0xee0 net/core/rtnetlink.c:5615
netlink_rcv_skb+0x1cf/0x410 net/netlink/af_netlink.c:2503
netlink_unicast_kernel net/netlink/af_netlink.c:1326 [inline]
netlink_unicast+0x7b6/0x980 net/netlink/af_netlink.c:1352
netlink_sendmsg+0xa30/0xd60 net/netlink/af_netlink.c:1920
sock_sendmsg_nosec net/socket.c:704 [inline]
__sock_sendmsg net/socket.c:716 [inline]
__sys_sendto+0x564/0x720 net/socket.c:2058
__do_sys_sendto net/socket.c:2070 [inline]
__se_sys_sendto net/socket.c:2066 [inline]
__x64_sys_sendto+0xda/0xf0 net/socket.c:2066
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
__sock_sendmsg net/socket.c:716 [inline]
__sys_sendto+0x564/0x720 net/socket.c:2058
__do_sys_sendto net/socket.c:2070 [inline]
__se_sys_sendto net/socket.c:2066 [inline]
__x64_sys_sendto+0xda/0xf0 net/socket.c:2066
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7ff327043e8c
RSP: 002b:00007ffe8a45a570 EFLAGS: 00000293 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007ff327d28620 RCX: 00007ff327043e8c
RDX: 000000000000003c RSI: 00007ff327d28670 RDI: 0000000000000003
RBP: 0000000000000000 R08: 00007ffe8a45a5c4 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000003
R13: 0000000000000000 R14: 00007ff327d28670 R15: 0000000000000000
</TASK>
INFO: task syz-executor:3895 blocked for more than 149 seconds.
Not tainted 5.15.167-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor state:D stack:27064 pid: 3895 ppid: 1 flags:0x00004004
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5027 [inline]
__schedule+0x12c4/0x45b0 kernel/sched/core.c:6373
schedule+0x11b/0x1f0 kernel/sched/core.c:6456
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6515
__mutex_lock_common+0xe34/0x25a0 kernel/locking/mutex.c:669
__mutex_lock kernel/locking/mutex.c:729 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
rtnl_lock net/core/rtnetlink.c:72 [inline]
__mutex_lock kernel/locking/mutex.c:729 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
rtnetlink_rcv_msg+0x94c/0xee0 net/core/rtnetlink.c:5615
netlink_rcv_skb+0x1cf/0x410 net/netlink/af_netlink.c:2503
netlink_unicast_kernel net/netlink/af_netlink.c:1326 [inline]
netlink_unicast+0x7b6/0x980 net/netlink/af_netlink.c:1352
netlink_sendmsg+0xa30/0xd60 net/netlink/af_netlink.c:1920
sock_sendmsg_nosec net/socket.c:704 [inline]
__sock_sendmsg net/socket.c:716 [inline]
__sys_sendto+0x564/0x720 net/socket.c:2058
__do_sys_sendto net/socket.c:2070 [inline]
__se_sys_sendto net/socket.c:2066 [inline]
__x64_sys_sendto+0xda/0xf0 net/socket.c:2066
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
__sock_sendmsg net/socket.c:716 [inline]
__sys_sendto+0x564/0x720 net/socket.c:2058
__do_sys_sendto net/socket.c:2070 [inline]
__se_sys_sendto net/socket.c:2066 [inline]
__x64_sys_sendto+0xda/0xf0 net/socket.c:2066
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fb0ff850e8c
RSP: 002b:00007ffce5bb8d90 EFLAGS: 00000293 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007fb100535620 RCX: 00007fb0ff850e8c
RDX: 0000000000000028 RSI: 00007fb100535670 RDI: 0000000000000003
RBP: 0000000000000000 R08: 00007ffce5bb8de4 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000003
R13: 0000000000000000 R14: 00007fb100535670 R15: 0000000000000000
</TASK>
INFO: task syz-executor:3897 blocked for more than 154 seconds.
Not tainted 5.15.167-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor state:D stack:27064 pid: 3897 ppid: 1 flags:0x00004004
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5027 [inline]
__schedule+0x12c4/0x45b0 kernel/sched/core.c:6373
schedule+0x11b/0x1f0 kernel/sched/core.c:6456
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6515
__mutex_lock_common+0xe34/0x25a0 kernel/locking/mutex.c:669
__mutex_lock kernel/locking/mutex.c:729 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
---
__mutex_lock kernel/locking/mutex.c:729 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
If you want syzbot to run the reproducer, reply with:
#syz test: git://repo/address.git branch-or-commit-hash
If you attach or paste a git patch, syzbot will apply it before testing.
syzbot
Sep 25, 2025, 3:32:35 AM (yesterday) Sep 25
to syzkaller...@googlegroups.com
syzbot has found a reproducer for the following issue on:
HEAD commit: 43bb85222e53 Linux 5.15.193
git tree: linux-5.15.y
console output: https://syzkaller.appspot.com/x/log.txt?x=15db6142580000
kernel config: https://syzkaller.appspot.com/x/.config?x=e1bb6d24ef2164eb
dashboard link: https://syzkaller.appspot.com/bug?extid=ccc611a0c79fb895b37f
compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=172c34e2580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=163d9ce2580000
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/0bc183664ae8/disk-43bb8522.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/0fc2f6618934/vmlinux-43bb8522.xz
kernel image: https://storage.googleapis.com/syzbot-assets/af70b3957f4c/bzImage-43bb8522.xz
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+ccc611...@syzkaller.appspotmail.com
INFO: task kworker/0:0:7 blocked for more than 143 seconds.
Not tainted syzkaller #0
__schedule+0x11bb/0x4390 kernel/sched/core.c:6395
schedule+0x11b/0x1e0 kernel/sched/core.c:6478
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6537
__mutex_lock_common+0xc71/0x2390 kernel/locking/mutex.c:669
process_one_work+0x863/0x1000 kernel/workqueue.c:2310
worker_thread+0xaa8/0x12a0 kernel/workqueue.c:2457
kthread+0x436/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
</TASK>
INFO: task kworker/u4:2:154 blocked for more than 143 seconds.
Not tainted syzkaller #0
Workqueue: events_unbound linkwatch_event
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11bb/0x4390 kernel/sched/core.c:6395
schedule+0x11b/0x1e0 kernel/sched/core.c:6478
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6537
__mutex_lock_common+0xc71/0x2390 kernel/locking/mutex.c:669
worker_thread+0xaa8/0x12a0 kernel/workqueue.c:2457
kthread+0x436/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
</TASK>
INFO: task kworker/u4:4:1275 blocked for more than 143 seconds.
Not tainted syzkaller #0
Workqueue: netns cleanup_net
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11bb/0x4390 kernel/sched/core.c:6395
schedule+0x11b/0x1e0 kernel/sched/core.c:6478
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6537
__mutex_lock_common+0xc71/0x2390 kernel/locking/mutex.c:669
ip6gre_exit_batch_net+0x44a/0x490 net/ipv6/ip6_gre.c:1651
ops_exit_list net/core/net_namespace.c:177 [inline]
cleanup_net+0x77b/0xb80 net/core/net_namespace.c:635
process_one_work+0x863/0x1000 kernel/workqueue.c:2310
worker_thread+0xaa8/0x12a0 kernel/workqueue.c:2457
kthread+0x436/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
</TASK>
INFO: task dhcpcd:3854 blocked for more than 144 seconds.
Not tainted syzkaller #0
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11bb/0x4390 kernel/sched/core.c:6395
schedule+0x11b/0x1e0 kernel/sched/core.c:6478
percpu_rwsem_wait+0x2d8/0x310 kernel/locking/percpu-rwsem.c:160
__percpu_down_read+0xc9/0x100 kernel/locking/percpu-rwsem.c:174
percpu_down_read include/linux/percpu-rwsem.h:65 [inline]
cgroup_threadgroup_change_begin include/linux/cgroup-defs.h:724 [inline]
cgroup_css_set_fork kernel/cgroup/cgroup.c:6196 [inline]
cgroup_can_fork+0xc94/0xda0 kernel/cgroup/cgroup.c:6314
copy_process+0x2290/0x3e00 kernel/fork.c:2382
kernel_clone+0x219/0x930 kernel/fork.c:2679
__do_sys_clone kernel/fork.c:2796 [inline]
__se_sys_clone kernel/fork.c:2780 [inline]
__x64_sys_clone+0x170/0x1c0 kernel/fork.c:2780
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fc84a08b636
RSP: 002b:00007ffcd6db0ac0 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 00007ffcd6db0ac8 RCX: 00007fc84a08b636
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 00007ffcd6dd1010 R08: 0000000000000000 R09: 0000000000000001
R10: 00007fc849fb7a10 R11: 0000000000000246 R12: 00007ffcd6db0c00
R13: 0000000000000000 R14: 0000000000000000 R15: 000055dce0e3dac0
</TASK>
INFO: task udevd:4213 blocked for more than 144 seconds.
Not tainted syzkaller #0
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11bb/0x4390 kernel/sched/core.c:6395
schedule+0x11b/0x1e0 kernel/sched/core.c:6478
percpu_rwsem_wait+0x2d8/0x310 kernel/locking/percpu-rwsem.c:160
__percpu_down_read+0xc9/0x100 kernel/locking/percpu-rwsem.c:174
percpu_down_read include/linux/percpu-rwsem.h:65 [inline]
cgroup_threadgroup_change_begin include/linux/cgroup-defs.h:724 [inline]
exit_signals+0x3e5/0x510 kernel/signal.c:2991
do_exit+0x256/0x20a0 kernel/exit.c:830
do_group_exit+0x12e/0x300 kernel/exit.c:997
__do_sys_exit_group kernel/exit.c:1008 [inline]
__se_sys_exit_group kernel/exit.c:1006 [inline]
__x64_sys_exit_group+0x3b/0x40 kernel/exit.c:1006
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fd21f0b36c5
RSP: 002b:00007fffb6b79a78 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 00005556bfa36f80 RCX: 00007fd21f0b36c5
RDX: 00000000000000e7 RSI: fffffffffffffe68 RDI: 0000000000000000
RBP: 00005556bfa12910 R08: 0000000000000000 R09: 0000000000000000
</TASK>
INFO: task udevd:4215 blocked for more than 144 seconds.
Not tainted syzkaller #0
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11bb/0x4390 kernel/sched/core.c:6395
schedule+0x11b/0x1e0 kernel/sched/core.c:6478
percpu_rwsem_wait+0x2d8/0x310 kernel/locking/percpu-rwsem.c:160
__percpu_down_read+0xc9/0x100 kernel/locking/percpu-rwsem.c:174
percpu_down_read include/linux/percpu-rwsem.h:65 [inline]
cgroup_threadgroup_change_begin include/linux/cgroup-defs.h:724 [inline]
exit_signals+0x3e5/0x510 kernel/signal.c:2991
do_exit+0x256/0x20a0 kernel/exit.c:830
do_group_exit+0x12e/0x300 kernel/exit.c:997
__do_sys_exit_group kernel/exit.c:1008 [inline]
__se_sys_exit_group kernel/exit.c:1006 [inline]
__x64_sys_exit_group+0x3b/0x40 kernel/exit.c:1006
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fd21f0b36c5
RSP: 002b:00007fffb6b79a78 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 00005556bfa37970 RCX: 00007fd21f0b36c5
RDX: 00000000000000e7 RSI: fffffffffffffe68 RDI: 0000000000000000
RBP: 00005556bfa12910 R08: 0000000000000000 R09: 0000000000000000
</TASK>
INFO: task syz-executor:4328 blocked for more than 144 seconds.
Not tainted syzkaller #0
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11bb/0x4390 kernel/sched/core.c:6395
schedule+0x11b/0x1e0 kernel/sched/core.c:6478
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6537
__mutex_lock_common+0xc71/0x2390 kernel/locking/mutex.c:669
rtnetlink_rcv_msg+0x974/0xe60 net/core/rtnetlink.c:5647
netlink_rcv_skb+0x1e0/0x430 net/netlink/af_netlink.c:2507
netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
netlink_unicast+0x774/0x920 net/netlink/af_netlink.c:1344
netlink_sendmsg+0x8ab/0xbc0 net/netlink/af_netlink.c:1918
__do_sys_sendto net/socket.c:2075 [inline]
__se_sys_sendto net/socket.c:2071 [inline]
__x64_sys_sendto+0xda/0xf0 net/socket.c:2071
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f60d7c4ad5c
RSP: 002b:00007ffd6ebbd060 EFLAGS: 00000293 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f60d89ce620 RCX: 00007f60d7c4ad5c
RDX: 000000000000002c RSI: 00007f60d89ce670 RDI: 0000000000000003
RBP: 0000000000000000 R08: 00007ffd6ebbd0b4 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000003
R13: 0000000000000000 R14: 00007f60d89ce670 R15: 0000000000000000
</TASK>
INFO: task udevd:4329 blocked for more than 144 seconds.
Not tainted syzkaller #0
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11bb/0x4390 kernel/sched/core.c:6395
schedule+0x11b/0x1e0 kernel/sched/core.c:6478
percpu_rwsem_wait+0x2d8/0x310 kernel/locking/percpu-rwsem.c:160
__percpu_down_read+0xc9/0x100 kernel/locking/percpu-rwsem.c:174
percpu_down_read include/linux/percpu-rwsem.h:65 [inline]
cgroup_threadgroup_change_begin include/linux/cgroup-defs.h:724 [inline]
exit_signals+0x3e5/0x510 kernel/signal.c:2991
do_exit+0x256/0x20a0 kernel/exit.c:830
do_group_exit+0x12e/0x300 kernel/exit.c:997
__do_sys_exit_group kernel/exit.c:1008 [inline]
__se_sys_exit_group kernel/exit.c:1006 [inline]
__x64_sys_exit_group+0x3b/0x40 kernel/exit.c:1006
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fd21f0b36c5
RSP: 002b:00007fffb6b79a78 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 00005556bfa3caa0 RCX: 00007fd21f0b36c5
RDX: 00000000000000e7 RSI: fffffffffffffe68 RDI: 0000000000000000
RBP: 00005556bfa12910 R08: 0000000000000000 R09: 0000000000000000
</TASK>
INFO: task syz-executor:4331 blocked for more than 145 seconds.
Not tainted syzkaller #0
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11bb/0x4390 kernel/sched/core.c:6395
schedule+0x11b/0x1e0 kernel/sched/core.c:6478
rwsem_down_write_slowpath+0xc46/0x11f0 kernel/locking/rwsem.c:1165
mmap_write_lock include/linux/mmap_lock.h:71 [inline]
mpol_rebind_mm+0x33/0x2c0 mm/mempolicy.c:381
cpuset_attach+0x330/0x5f0 kernel/cgroup/cpuset.c:2376
cgroup_migrate_execute+0x7eb/0x1010 kernel/cgroup/cgroup.c:2574
cgroup_attach_task+0x562/0x7e0 kernel/cgroup/cgroup.c:2869
__cgroup1_procs_write+0x2e5/0x3f0 kernel/cgroup/cgroup-v1.c:527
cgroup_file_write+0x2f7/0x630 kernel/cgroup/cgroup.c:3943
kernfs_fop_write_iter+0x379/0x4c0 fs/kernfs/file.c:296
call_write_iter include/linux/fs.h:2172 [inline]
new_sync_write fs/read_write.c:507 [inline]
vfs_write+0x712/0xd00 fs/read_write.c:594
ksys_write+0x14d/0x250 fs/read_write.c:647
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fc42510497f
RSP: 002b:00007ffcd713feb0 EFLAGS: 00000293 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007fc42510497f
RDX: 0000000000000001 RSI: 00007ffcd713ff00 RDI: 0000000000000003
RBP: 00007ffcd7140470 R08: 0000000000000000 R09: 00007ffcd713fd07
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000001
R13: 00007ffcd713ff00 R14: 00007ffcd7140430 R15: 00007ffcd7140470
</TASK>
INFO: task kworker/1:5:4398 blocked for more than 145 seconds.
Not tainted syzkaller #0
__schedule+0x11bb/0x4390 kernel/sched/core.c:6395
schedule+0x11b/0x1e0 kernel/sched/core.c:6478
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6537
__mutex_lock_common+0xc71/0x2390 kernel/locking/mutex.c:669
process_one_work+0x863/0x1000 kernel/workqueue.c:2310
worker_thread+0xaa8/0x12a0 kernel/workqueue.c:2457
kthread+0x436/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
#0: ffffffff8c1420f0 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: copy_process+0x2290/0x3e00 kernel/fork.c:2382
3 locks held by kworker/0:0/7:
#0: ffff88814c11f138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1
#1: ffffc90000cc7d00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285
#2: ffffffff8d238048 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xc4/0x1520 net/ipv6/addrconf.c:4110
3 locks held by kworker/1:1/23:
#0: ffff888016871938 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1
#1: ffffc90000ddfd00 ((reg_check_chans).work){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285
#2: ffffffff8d238048 (rtnl_mutex){+.+.}-{3:3}, at: reg_check_chans_work+0x81/0xa50 net/wireless/reg.c:2437
3 locks held by kworker/u4:2/154:
#0: ffff888016879138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1
#1: ffffc90002017d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285
#2: ffffffff8d238048 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xa/0x50 net/core/link_watch.c:251
4 locks held by kworker/u4:4/1275:
#0: ffff8880169cd938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1
#1: ffffc90004fdfd00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285
#2: ffffffff8d22c3d0 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x132/0xb80 net/core/net_namespace.c:589
#3: ffffffff8d238048 (rtnl_mutex){+.+.}-{3:3}, at: netdev_run_todo+0x86b/0xa40 net/core/dev.c:10696
1 lock held by dhcpcd/3854:
#0: ffffffff8c1420f0 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: copy_process+0x2290/0x3e00 kernel/fork.c:2382
2 locks held by getty/3949:
#0: ffff88814cd38098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
#1: ffffc900026562e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x5ba/0x1a30 drivers/tty/n_tty.c:2158
1 lock held by udevd/4213:
#0: ffffffff8c1420f0 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: do_exit+0x256/0x20a0 kernel/exit.c:830
1 lock held by udevd/4215:
#0: ffffffff8c1420f0 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: do_exit+0x256/0x20a0 kernel/exit.c:830
1 lock held by syz-executor/4317:
#0: ffffffff8c1420f0 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: do_exit+0x256/0x20a0 kernel/exit.c:830
2 locks held by syz-executor/4319:
#0: ffffffff8c1a66f0 (dup_mmap_sem){.+.+}-{0:0}, at: dup_mmap kernel/fork.c:503 [inline]
#0: ffffffff8c1a66f0 (dup_mmap_sem){.+.+}-{0:0}, at: dup_mm kernel/fork.c:1466 [inline]
#0: ffffffff8c1a66f0 (dup_mmap_sem){.+.+}-{0:0}, at: copy_mm+0x21f/0x1380 kernel/fork.c:1518
#1: ffff8880750a5528 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock_killable include/linux/mmap_lock.h:87 [inline]
#1: ffff8880750a5528 (&mm->mmap_lock){++++}-{3:3}, at: dup_mmap kernel/fork.c:504 [inline]
#1: ffff8880750a5528 (&mm->mmap_lock){++++}-{3:3}, at: dup_mm kernel/fork.c:1466 [inline]
#1: ffff8880750a5528 (&mm->mmap_lock){++++}-{3:3}, at: copy_mm+0x238/0x1380 kernel/fork.c:1518
2 locks held by syz-executor/4322:
#0: ffffffff8c1a66f0 (dup_mmap_sem){.+.+}-{0:0}, at: dup_mmap kernel/fork.c:503 [inline]
#0: ffffffff8c1a66f0 (dup_mmap_sem){.+.+}-{0:0}, at: dup_mm kernel/fork.c:1466 [inline]
#0: ffffffff8c1a66f0 (dup_mmap_sem){.+.+}-{0:0}, at: copy_mm+0x21f/0x1380 kernel/fork.c:1518
#1: ffff8880750a6328 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock_killable include/linux/mmap_lock.h:87 [inline]
#1: ffff8880750a6328 (&mm->mmap_lock){++++}-{3:3}, at: dup_mmap kernel/fork.c:504 [inline]
#1: ffff8880750a6328 (&mm->mmap_lock){++++}-{3:3}, at: dup_mm kernel/fork.c:1466 [inline]
#1: ffff8880750a6328 (&mm->mmap_lock){++++}-{3:3}, at: copy_mm+0x238/0x1380 kernel/fork.c:1518
1 lock held by syz-executor/4328:
#0: ffffffff8d238048 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline]
#0: ffffffff8d238048 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x974/0xe60 net/core/rtnetlink.c:5647
1 lock held by udevd/4329:
#0: ffffffff8c1420f0 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: do_exit+0x256/0x20a0 kernel/exit.c:830
7 locks held by syz-executor/4331:
#0: ffff888079ab6460 (sb_writers#11){.+.+}-{0:0}, at: vfs_write+0x28a/0xd00 fs/read_write.c:590
#1: ffff88807ae4e888 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1e5/0x4c0 fs/kernfs/file.c:287
#2: ffffffff8c141f08 (cgroup_mutex){+.+.}-{3:3}, at: cgroup_kn_lock_live+0xee/0x230 kernel/cgroup/cgroup.c:1639
#3: ffffffff8bfbadd0 (cpu_hotplug_lock){++++}-{0:0}, at: cgroup_attach_lock kernel/cgroup/cgroup.c:2388 [inline]
#3: ffffffff8bfbadd0 (cpu_hotplug_lock){++++}-{0:0}, at: cgroup_procs_write_start+0x17c/0x580 kernel/cgroup/cgroup.c:2898
#4: ffffffff8c1420f0 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: cgroup_attach_lock kernel/cgroup/cgroup.c:2390 [inline]
#4: ffffffff8c1420f0 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: cgroup_procs_write_start+0x192/0x580 kernel/cgroup/cgroup.c:2898
#5: ffffffff8c14f948 (cpuset_mutex){+.+.}-{3:3}, at: cpuset_attach+0xac/0x5f0 kernel/cgroup/cpuset.c:2348
#6: ffff88802b2e4728 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock include/linux/mmap_lock.h:71 [inline]
#6: ffff88802b2e4728 (&mm->mmap_lock){++++}-{3:3}, at: mpol_rebind_mm+0x33/0x2c0 mm/mempolicy.c:381
4 locks held by syz-executor/4332:
#0: ffffffff8d294cd0 (cb_lock){++++}-{3:3}, at: genl_rcv+0x15/0x40 net/netlink/genetlink.c:802
#1: ffffffff8d294b28 (genl_mutex){+.+.}-{3:3}, at: genl_lock net/netlink/genetlink.c:33 [inline]
#1: ffffffff8d294b28 (genl_mutex){+.+.}-{3:3}, at: genl_rcv_msg+0x137/0xf40 net/netlink/genetlink.c:790
#2: ffffffff8d238048 (rtnl_mutex){+.+.}-{3:3}, at: wg_set_device+0xf2/0x1e70 drivers/net/wireguard/netlink.c:504
#3: ffff8880790193e8 (&wg->device_update_lock){+.+.}-{3:3}, at: wg_set_device+0x10a/0x1e70 drivers/net/wireguard/netlink.c:505
3 locks held by kworker/1:5/4398:
#0: ffff88814c11f138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1
#1: ffffc90002ebfd00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285
#2: ffffffff8d238048 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xc4/0x1520 net/ipv6/addrconf.c:4110
=============================================
NMI backtrace for cpu 1
CPU: 1 PID: 27 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
Call Trace:
<TASK>
dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106
nmi_cpu_backtrace+0x397/0x3d0 lib/nmi_backtrace.c:111
nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:212 [inline]
watchdog+0xe0f/0xe50 kernel/hung_task.c:369
kthread+0x436/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
</TASK>
Sending NMI from CPU 1 to CPUs 0:
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
Workqueue: bat_events batadv_nc_worker
RIP: 0010:native_save_fl arch/x86/include/asm/irqflags.h:29 [inline]
RIP: 0010:arch_local_save_flags arch/x86/include/asm/irqflags.h:70 [inline]
RIP: 0010:arch_irqs_disabled arch/x86/include/asm/irqflags.h:132 [inline]
RIP: 0010:lock_release+0x55e/0x870 kernel/locking/lockdep.c:5646
Code: 48 c7 c7 c0 2a 0b 8a e8 80 80 4c 08 b8 ff ff ff ff 65 0f c1 05 33 fa a5 7e 83 f8 01 75 75 48 c7 84 24 80 00 00 00 00 00 00 00 <9c> 8f 84 24 80 00 00 00 f6 84 24 81 00 00 00 02 75 75 f7 44 24 50
RSP: 0018:ffffc9000436fa00 EFLAGS: 00000046
RAX: 0000000000000001 RBX: 18f62d8b2df283a7 RCX: 2fb39e0bfb583900
RDX: 0000000000000002 RSI: ffffffff8a0b2ac0 RDI: ffffffff8a59a480
RBP: ffffc9000436fb20 R08: dffffc0000000000 R09: fffffbfff1ad323e
R10: fffffbfff1ad323e R11: 1ffffffff1ad323d R12: ffff88801fee0b40
R13: dffffc0000000000 R14: ffff88801fee0ae0 R15: 1ffff9200086df4c
FS: 0000000000000000(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
__raw_spin_unlock_bh include/linux/spinlock_api_smp.h:174 [inline]
_raw_spin_unlock_bh+0x17/0x30 kernel/locking/spinlock.c:210
spin_unlock_bh include/linux/spinlock.h:408 [inline]
batadv_nc_purge_paths+0x316/0x3b0 net/batman-adv/network-coding.c:475
batadv_nc_worker+0x327/0x5c0 net/batman-adv/network-coding.c:726
process_one_work+0x863/0x1000 kernel/workqueue.c:2310
worker_thread+0xaa8/0x12a0 kernel/workqueue.c:2457
kthread+0x436/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
</TASK>
HEAD commit: 43bb85222e53 Linux 5.15.193
git tree: linux-5.15.y
console output: https://syzkaller.appspot.com/x/log.txt?x=15db6142580000
kernel config: https://syzkaller.appspot.com/x/.config?x=e1bb6d24ef2164eb
dashboard link: https://syzkaller.appspot.com/bug?extid=ccc611a0c79fb895b37f
compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=172c34e2580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=163d9ce2580000
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/0bc183664ae8/disk-43bb8522.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/0fc2f6618934/vmlinux-43bb8522.xz
kernel image: https://storage.googleapis.com/syzbot-assets/af70b3957f4c/bzImage-43bb8522.xz
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+ccc611...@syzkaller.appspotmail.com
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/0:0 state:D stack:25312 pid: 7 ppid: 2 flags:0x00004000
Workqueue: ipv6_addrconf addrconf_dad_work
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5049 [inline]
Call Trace:
<TASK>
__schedule+0x11bb/0x4390 kernel/sched/core.c:6395
schedule+0x11b/0x1e0 kernel/sched/core.c:6478
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6537
__mutex_lock_common+0xc71/0x2390 kernel/locking/mutex.c:669
__mutex_lock kernel/locking/mutex.c:729 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
addrconf_dad_work+0xc4/0x1520 net/ipv6/addrconf.c:4110
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
process_one_work+0x863/0x1000 kernel/workqueue.c:2310
worker_thread+0xaa8/0x12a0 kernel/workqueue.c:2457
kthread+0x436/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
</TASK>
INFO: task kworker/u4:2:154 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u4:2 state:D stack:25504 pid: 154 ppid: 2 flags:0x00004000
Workqueue: events_unbound linkwatch_event
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11bb/0x4390 kernel/sched/core.c:6395
schedule+0x11b/0x1e0 kernel/sched/core.c:6478
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6537
__mutex_lock_common+0xc71/0x2390 kernel/locking/mutex.c:669
__mutex_lock kernel/locking/mutex.c:729 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
linkwatch_event+0xa/0x50 net/core/link_watch.c:251
process_one_work+0x863/0x1000 kernel/workqueue.c:2310
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
linkwatch_event+0xa/0x50 net/core/link_watch.c:251
worker_thread+0xaa8/0x12a0 kernel/workqueue.c:2457
kthread+0x436/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
</TASK>
INFO: task kworker/u4:4:1275 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u4:4 state:D stack:25000 pid: 1275 ppid: 2 flags:0x00004000
Workqueue: netns cleanup_net
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11bb/0x4390 kernel/sched/core.c:6395
schedule+0x11b/0x1e0 kernel/sched/core.c:6478
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6537
__mutex_lock_common+0xc71/0x2390 kernel/locking/mutex.c:669
__mutex_lock kernel/locking/mutex.c:729 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
netdev_run_todo+0x86b/0xa40 net/core/dev.c:10696
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
ip6gre_exit_batch_net+0x44a/0x490 net/ipv6/ip6_gre.c:1651
ops_exit_list net/core/net_namespace.c:177 [inline]
cleanup_net+0x77b/0xb80 net/core/net_namespace.c:635
process_one_work+0x863/0x1000 kernel/workqueue.c:2310
worker_thread+0xaa8/0x12a0 kernel/workqueue.c:2457
kthread+0x436/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
</TASK>
INFO: task dhcpcd:3854 blocked for more than 144 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:dhcpcd state:D stack:21376 pid: 3854 ppid: 3853 flags:0x00004002
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11bb/0x4390 kernel/sched/core.c:6395
schedule+0x11b/0x1e0 kernel/sched/core.c:6478
percpu_rwsem_wait+0x2d8/0x310 kernel/locking/percpu-rwsem.c:160
__percpu_down_read+0xc9/0x100 kernel/locking/percpu-rwsem.c:174
percpu_down_read include/linux/percpu-rwsem.h:65 [inline]
cgroup_threadgroup_change_begin include/linux/cgroup-defs.h:724 [inline]
cgroup_css_set_fork kernel/cgroup/cgroup.c:6196 [inline]
cgroup_can_fork+0xc94/0xda0 kernel/cgroup/cgroup.c:6314
copy_process+0x2290/0x3e00 kernel/fork.c:2382
kernel_clone+0x219/0x930 kernel/fork.c:2679
__do_sys_clone kernel/fork.c:2796 [inline]
__se_sys_clone kernel/fork.c:2780 [inline]
__x64_sys_clone+0x170/0x1c0 kernel/fork.c:2780
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fc84a08b636
RSP: 002b:00007ffcd6db0ac0 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 00007ffcd6db0ac8 RCX: 00007fc84a08b636
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 00007ffcd6dd1010 R08: 0000000000000000 R09: 0000000000000001
R10: 00007fc849fb7a10 R11: 0000000000000246 R12: 00007ffcd6db0c00
R13: 0000000000000000 R14: 0000000000000000 R15: 000055dce0e3dac0
</TASK>
INFO: task udevd:4213 blocked for more than 144 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:udevd state:D stack:27200 pid: 4213 ppid: 3561 flags:0x00004002
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11bb/0x4390 kernel/sched/core.c:6395
schedule+0x11b/0x1e0 kernel/sched/core.c:6478
percpu_rwsem_wait+0x2d8/0x310 kernel/locking/percpu-rwsem.c:160
__percpu_down_read+0xc9/0x100 kernel/locking/percpu-rwsem.c:174
percpu_down_read include/linux/percpu-rwsem.h:65 [inline]
cgroup_threadgroup_change_begin include/linux/cgroup-defs.h:724 [inline]
exit_signals+0x3e5/0x510 kernel/signal.c:2991
do_exit+0x256/0x20a0 kernel/exit.c:830
do_group_exit+0x12e/0x300 kernel/exit.c:997
__do_sys_exit_group kernel/exit.c:1008 [inline]
__se_sys_exit_group kernel/exit.c:1006 [inline]
__x64_sys_exit_group+0x3b/0x40 kernel/exit.c:1006
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fd21f0b36c5
RSP: 002b:00007fffb6b79a78 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 00005556bfa36f80 RCX: 00007fd21f0b36c5
RDX: 00000000000000e7 RSI: fffffffffffffe68 RDI: 0000000000000000
RBP: 00005556bfa12910 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fffb6b79ac0 R14: 0000000000000000 R15: 0000000000000000
</TASK>
INFO: task udevd:4215 blocked for more than 144 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:udevd state:D stack:26368 pid: 4215 ppid: 3561 flags:0x00004002
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11bb/0x4390 kernel/sched/core.c:6395
schedule+0x11b/0x1e0 kernel/sched/core.c:6478
percpu_rwsem_wait+0x2d8/0x310 kernel/locking/percpu-rwsem.c:160
__percpu_down_read+0xc9/0x100 kernel/locking/percpu-rwsem.c:174
percpu_down_read include/linux/percpu-rwsem.h:65 [inline]
cgroup_threadgroup_change_begin include/linux/cgroup-defs.h:724 [inline]
exit_signals+0x3e5/0x510 kernel/signal.c:2991
do_exit+0x256/0x20a0 kernel/exit.c:830
do_group_exit+0x12e/0x300 kernel/exit.c:997
__do_sys_exit_group kernel/exit.c:1008 [inline]
__se_sys_exit_group kernel/exit.c:1006 [inline]
__x64_sys_exit_group+0x3b/0x40 kernel/exit.c:1006
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fd21f0b36c5
RSP: 002b:00007fffb6b79a78 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 00005556bfa37970 RCX: 00007fd21f0b36c5
RDX: 00000000000000e7 RSI: fffffffffffffe68 RDI: 0000000000000000
RBP: 00005556bfa12910 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fffb6b79ac0 R14: 0000000000000000 R15: 0000000000000000
</TASK>
INFO: task syz-executor:4328 blocked for more than 144 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor state:D stack:21792 pid: 4328 ppid: 4324 flags:0x00004000
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11bb/0x4390 kernel/sched/core.c:6395
schedule+0x11b/0x1e0 kernel/sched/core.c:6478
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6537
__mutex_lock_common+0xc71/0x2390 kernel/locking/mutex.c:669
__mutex_lock kernel/locking/mutex.c:729 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
rtnl_lock net/core/rtnetlink.c:72 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
rtnetlink_rcv_msg+0x974/0xe60 net/core/rtnetlink.c:5647
netlink_rcv_skb+0x1e0/0x430 net/netlink/af_netlink.c:2507
netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
netlink_unicast+0x774/0x920 net/netlink/af_netlink.c:1344
netlink_sendmsg+0x8ab/0xbc0 net/netlink/af_netlink.c:1918
sock_sendmsg_nosec net/socket.c:704 [inline]
__sock_sendmsg net/socket.c:716 [inline]
__sys_sendto+0x423/0x580 net/socket.c:2063
__sock_sendmsg net/socket.c:716 [inline]
__do_sys_sendto net/socket.c:2075 [inline]
__se_sys_sendto net/socket.c:2071 [inline]
__x64_sys_sendto+0xda/0xf0 net/socket.c:2071
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f60d7c4ad5c
RSP: 002b:00007ffd6ebbd060 EFLAGS: 00000293 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f60d89ce620 RCX: 00007f60d7c4ad5c
RDX: 000000000000002c RSI: 00007f60d89ce670 RDI: 0000000000000003
RBP: 0000000000000000 R08: 00007ffd6ebbd0b4 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000003
R13: 0000000000000000 R14: 00007f60d89ce670 R15: 0000000000000000
</TASK>
INFO: task udevd:4329 blocked for more than 144 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:udevd state:D stack:27328 pid: 4329 ppid: 3561 flags:0x00004002
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11bb/0x4390 kernel/sched/core.c:6395
schedule+0x11b/0x1e0 kernel/sched/core.c:6478
percpu_rwsem_wait+0x2d8/0x310 kernel/locking/percpu-rwsem.c:160
__percpu_down_read+0xc9/0x100 kernel/locking/percpu-rwsem.c:174
percpu_down_read include/linux/percpu-rwsem.h:65 [inline]
cgroup_threadgroup_change_begin include/linux/cgroup-defs.h:724 [inline]
exit_signals+0x3e5/0x510 kernel/signal.c:2991
do_exit+0x256/0x20a0 kernel/exit.c:830
do_group_exit+0x12e/0x300 kernel/exit.c:997
__do_sys_exit_group kernel/exit.c:1008 [inline]
__se_sys_exit_group kernel/exit.c:1006 [inline]
__x64_sys_exit_group+0x3b/0x40 kernel/exit.c:1006
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fd21f0b36c5
RSP: 002b:00007fffb6b79a78 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 00005556bfa3caa0 RCX: 00007fd21f0b36c5
RDX: 00000000000000e7 RSI: fffffffffffffe68 RDI: 0000000000000000
RBP: 00005556bfa12910 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fffb6b79ac0 R14: 0000000000000000 R15: 0000000000000000
</TASK>
INFO: task syz-executor:4331 blocked for more than 145 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor state:D stack:18344 pid: 4331 ppid: 4326 flags:0x00004000
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11bb/0x4390 kernel/sched/core.c:6395
schedule+0x11b/0x1e0 kernel/sched/core.c:6478
rwsem_down_write_slowpath+0xc46/0x11f0 kernel/locking/rwsem.c:1165
mmap_write_lock include/linux/mmap_lock.h:71 [inline]
mpol_rebind_mm+0x33/0x2c0 mm/mempolicy.c:381
cpuset_attach+0x330/0x5f0 kernel/cgroup/cpuset.c:2376
cgroup_migrate_execute+0x7eb/0x1010 kernel/cgroup/cgroup.c:2574
cgroup_attach_task+0x562/0x7e0 kernel/cgroup/cgroup.c:2869
__cgroup1_procs_write+0x2e5/0x3f0 kernel/cgroup/cgroup-v1.c:527
cgroup_file_write+0x2f7/0x630 kernel/cgroup/cgroup.c:3943
kernfs_fop_write_iter+0x379/0x4c0 fs/kernfs/file.c:296
call_write_iter include/linux/fs.h:2172 [inline]
new_sync_write fs/read_write.c:507 [inline]
vfs_write+0x712/0xd00 fs/read_write.c:594
ksys_write+0x14d/0x250 fs/read_write.c:647
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fc42510497f
RSP: 002b:00007ffcd713feb0 EFLAGS: 00000293 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007fc42510497f
RDX: 0000000000000001 RSI: 00007ffcd713ff00 RDI: 0000000000000003
RBP: 00007ffcd7140470 R08: 0000000000000000 R09: 00007ffcd713fd07
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000001
R13: 00007ffcd713ff00 R14: 00007ffcd7140430 R15: 00007ffcd7140470
</TASK>
INFO: task kworker/1:5:4398 blocked for more than 145 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/1:5 state:D stack:25288 pid: 4398 ppid: 2 flags:0x00004000
Workqueue: ipv6_addrconf addrconf_dad_work
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5049 [inline]
Call Trace:
<TASK>
__schedule+0x11bb/0x4390 kernel/sched/core.c:6395
schedule+0x11b/0x1e0 kernel/sched/core.c:6478
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6537
__mutex_lock_common+0xc71/0x2390 kernel/locking/mutex.c:669
__mutex_lock kernel/locking/mutex.c:729 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
addrconf_dad_work+0xc4/0x1520 net/ipv6/addrconf.c:4110
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
process_one_work+0x863/0x1000 kernel/workqueue.c:2310
worker_thread+0xaa8/0x12a0 kernel/workqueue.c:2457
kthread+0x436/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
</TASK>
Showing all locks held in the system:
1 lock held by kthreadd/2:
Showing all locks held in the system:
#0: ffffffff8c1420f0 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: copy_process+0x2290/0x3e00 kernel/fork.c:2382
3 locks held by kworker/0:0/7:
#0: ffff88814c11f138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1
#1: ffffc90000cc7d00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285
#2: ffffffff8d238048 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xc4/0x1520 net/ipv6/addrconf.c:4110
3 locks held by kworker/1:1/23:
#0: ffff888016871938 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1
#1: ffffc90000ddfd00 ((reg_check_chans).work){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285
#2: ffffffff8d238048 (rtnl_mutex){+.+.}-{3:3}, at: reg_check_chans_work+0x81/0xa50 net/wireless/reg.c:2437
1 lock held by khungtaskd/27:
#0: ffffffff8c11c660 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
3 locks held by kworker/u4:2/154:
#0: ffff888016879138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1
#1: ffffc90002017d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285
#2: ffffffff8d238048 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xa/0x50 net/core/link_watch.c:251
4 locks held by kworker/u4:4/1275:
#0: ffff8880169cd938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1
#1: ffffc90004fdfd00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285
#2: ffffffff8d22c3d0 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x132/0xb80 net/core/net_namespace.c:589
#3: ffffffff8d238048 (rtnl_mutex){+.+.}-{3:3}, at: netdev_run_todo+0x86b/0xa40 net/core/dev.c:10696
1 lock held by dhcpcd/3854:
#0: ffffffff8c1420f0 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: copy_process+0x2290/0x3e00 kernel/fork.c:2382
2 locks held by getty/3949:
#0: ffff88814cd38098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
#1: ffffc900026562e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x5ba/0x1a30 drivers/tty/n_tty.c:2158
1 lock held by udevd/4213:
#0: ffffffff8c1420f0 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: do_exit+0x256/0x20a0 kernel/exit.c:830
1 lock held by udevd/4215:
#0: ffffffff8c1420f0 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: do_exit+0x256/0x20a0 kernel/exit.c:830
1 lock held by syz-executor/4317:
#0: ffffffff8c1420f0 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: do_exit+0x256/0x20a0 kernel/exit.c:830
2 locks held by syz-executor/4319:
#0: ffffffff8c1a66f0 (dup_mmap_sem){.+.+}-{0:0}, at: dup_mmap kernel/fork.c:503 [inline]
#0: ffffffff8c1a66f0 (dup_mmap_sem){.+.+}-{0:0}, at: dup_mm kernel/fork.c:1466 [inline]
#0: ffffffff8c1a66f0 (dup_mmap_sem){.+.+}-{0:0}, at: copy_mm+0x21f/0x1380 kernel/fork.c:1518
#1: ffff8880750a5528 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock_killable include/linux/mmap_lock.h:87 [inline]
#1: ffff8880750a5528 (&mm->mmap_lock){++++}-{3:3}, at: dup_mmap kernel/fork.c:504 [inline]
#1: ffff8880750a5528 (&mm->mmap_lock){++++}-{3:3}, at: dup_mm kernel/fork.c:1466 [inline]
#1: ffff8880750a5528 (&mm->mmap_lock){++++}-{3:3}, at: copy_mm+0x238/0x1380 kernel/fork.c:1518
2 locks held by syz-executor/4322:
#0: ffffffff8c1a66f0 (dup_mmap_sem){.+.+}-{0:0}, at: dup_mmap kernel/fork.c:503 [inline]
#0: ffffffff8c1a66f0 (dup_mmap_sem){.+.+}-{0:0}, at: dup_mm kernel/fork.c:1466 [inline]
#0: ffffffff8c1a66f0 (dup_mmap_sem){.+.+}-{0:0}, at: copy_mm+0x21f/0x1380 kernel/fork.c:1518
#1: ffff8880750a6328 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock_killable include/linux/mmap_lock.h:87 [inline]
#1: ffff8880750a6328 (&mm->mmap_lock){++++}-{3:3}, at: dup_mmap kernel/fork.c:504 [inline]
#1: ffff8880750a6328 (&mm->mmap_lock){++++}-{3:3}, at: dup_mm kernel/fork.c:1466 [inline]
#1: ffff8880750a6328 (&mm->mmap_lock){++++}-{3:3}, at: copy_mm+0x238/0x1380 kernel/fork.c:1518
1 lock held by syz-executor/4328:
#0: ffffffff8d238048 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline]
#0: ffffffff8d238048 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x974/0xe60 net/core/rtnetlink.c:5647
1 lock held by udevd/4329:
#0: ffffffff8c1420f0 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: do_exit+0x256/0x20a0 kernel/exit.c:830
7 locks held by syz-executor/4331:
#0: ffff888079ab6460 (sb_writers#11){.+.+}-{0:0}, at: vfs_write+0x28a/0xd00 fs/read_write.c:590
#1: ffff88807ae4e888 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1e5/0x4c0 fs/kernfs/file.c:287
#2: ffffffff8c141f08 (cgroup_mutex){+.+.}-{3:3}, at: cgroup_kn_lock_live+0xee/0x230 kernel/cgroup/cgroup.c:1639
#3: ffffffff8bfbadd0 (cpu_hotplug_lock){++++}-{0:0}, at: cgroup_attach_lock kernel/cgroup/cgroup.c:2388 [inline]
#3: ffffffff8bfbadd0 (cpu_hotplug_lock){++++}-{0:0}, at: cgroup_procs_write_start+0x17c/0x580 kernel/cgroup/cgroup.c:2898
#4: ffffffff8c1420f0 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: cgroup_attach_lock kernel/cgroup/cgroup.c:2390 [inline]
#4: ffffffff8c1420f0 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: cgroup_procs_write_start+0x192/0x580 kernel/cgroup/cgroup.c:2898
#5: ffffffff8c14f948 (cpuset_mutex){+.+.}-{3:3}, at: cpuset_attach+0xac/0x5f0 kernel/cgroup/cpuset.c:2348
#6: ffff88802b2e4728 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock include/linux/mmap_lock.h:71 [inline]
#6: ffff88802b2e4728 (&mm->mmap_lock){++++}-{3:3}, at: mpol_rebind_mm+0x33/0x2c0 mm/mempolicy.c:381
4 locks held by syz-executor/4332:
#0: ffffffff8d294cd0 (cb_lock){++++}-{3:3}, at: genl_rcv+0x15/0x40 net/netlink/genetlink.c:802
#1: ffffffff8d294b28 (genl_mutex){+.+.}-{3:3}, at: genl_lock net/netlink/genetlink.c:33 [inline]
#1: ffffffff8d294b28 (genl_mutex){+.+.}-{3:3}, at: genl_rcv_msg+0x137/0xf40 net/netlink/genetlink.c:790
#2: ffffffff8d238048 (rtnl_mutex){+.+.}-{3:3}, at: wg_set_device+0xf2/0x1e70 drivers/net/wireguard/netlink.c:504
#3: ffff8880790193e8 (&wg->device_update_lock){+.+.}-{3:3}, at: wg_set_device+0x10a/0x1e70 drivers/net/wireguard/netlink.c:505
3 locks held by kworker/1:5/4398:
#0: ffff88814c11f138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1
#1: ffffc90002ebfd00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285
#2: ffffffff8d238048 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xc4/0x1520 net/ipv6/addrconf.c:4110
=============================================
NMI backtrace for cpu 1
CPU: 1 PID: 27 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
Call Trace:
<TASK>
dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106
nmi_cpu_backtrace+0x397/0x3d0 lib/nmi_backtrace.c:111
nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:212 [inline]
watchdog+0xe0f/0xe50 kernel/hung_task.c:369
kthread+0x436/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
</TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 867 Comm: kworker/u4:3 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
Workqueue: bat_events batadv_nc_worker
RIP: 0010:native_save_fl arch/x86/include/asm/irqflags.h:29 [inline]
RIP: 0010:arch_local_save_flags arch/x86/include/asm/irqflags.h:70 [inline]
RIP: 0010:arch_irqs_disabled arch/x86/include/asm/irqflags.h:132 [inline]
RIP: 0010:lock_release+0x55e/0x870 kernel/locking/lockdep.c:5646
Code: 48 c7 c7 c0 2a 0b 8a e8 80 80 4c 08 b8 ff ff ff ff 65 0f c1 05 33 fa a5 7e 83 f8 01 75 75 48 c7 84 24 80 00 00 00 00 00 00 00 <9c> 8f 84 24 80 00 00 00 f6 84 24 81 00 00 00 02 75 75 f7 44 24 50
RSP: 0018:ffffc9000436fa00 EFLAGS: 00000046
RAX: 0000000000000001 RBX: 18f62d8b2df283a7 RCX: 2fb39e0bfb583900
RDX: 0000000000000002 RSI: ffffffff8a0b2ac0 RDI: ffffffff8a59a480
RBP: ffffc9000436fb20 R08: dffffc0000000000 R09: fffffbfff1ad323e
R10: fffffbfff1ad323e R11: 1ffffffff1ad323d R12: ffff88801fee0b40
R13: dffffc0000000000 R14: ffff88801fee0ae0 R15: 1ffff9200086df4c
FS: 0000000000000000(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f70215a5fe8 CR3: 000000002542c000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
__raw_spin_unlock_bh include/linux/spinlock_api_smp.h:174 [inline]
_raw_spin_unlock_bh+0x17/0x30 kernel/locking/spinlock.c:210
spin_unlock_bh include/linux/spinlock.h:408 [inline]
batadv_nc_purge_paths+0x316/0x3b0 net/batman-adv/network-coding.c:475
batadv_nc_worker+0x327/0x5c0 net/batman-adv/network-coding.c:726
process_one_work+0x863/0x1000 kernel/workqueue.c:2310
worker_thread+0xaa8/0x12a0 kernel/workqueue.c:2457
kthread+0x436/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
</TASK>
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