syzbot


INFO: task hung in register_nexthop_notifier (5)

Status: auto-obsoleted due to no activity on 2025/05/26 10:08
Subsystems: netfilter
[Documentation on labels]
First crash: 235d, last: 139d
Similar bugs (5)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-5.15 INFO: task hung in register_nexthop_notifier 1 4 396d 419d 0/3 auto-obsoleted due to no activity on 2024/09/21 15:59
upstream INFO: task hung in register_nexthop_notifier net 1 1 1661d 1661d 0/29 auto-closed as invalid on 2021/03/26 11:18
upstream INFO: task hung in register_nexthop_notifier (2) net 1 1 1365d 1365d 0/29 auto-closed as invalid on 2022/01/16 12:31
upstream INFO: task hung in register_nexthop_notifier (3) net 1 44 373d 483d 26/29 fixed on 2024/07/09 19:14
linux-6.1 INFO: task hung in register_nexthop_notifier 1 3 392d 419d 0/3 auto-obsoleted due to no activity on 2024/09/25 01:20

Sample crash report:
INFO: task syz-executor:11070 blocked for more than 143 seconds.
      Not tainted 6.13.0-rc3-syzkaller-00301-gbcde95ce32b6 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D
 stack:26752 pid:11070 tgid:11070 ppid:1      flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5369 [inline]
 __schedule+0x1850/0x4c30 kernel/sched/core.c:6756
 __schedule_loop kernel/sched/core.c:6833 [inline]
 schedule+0x14b/0x320 kernel/sched/core.c:6848
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6905
 __mutex_lock_common kernel/locking/mutex.c:665 [inline]
 __mutex_lock+0x7e7/0xee0 kernel/locking/mutex.c:735
 register_nexthop_notifier+0x84/0x290 net/ipv4/nexthop.c:3878
 ops_init+0x31e/0x590 net/core/net_namespace.c:138
 setup_net+0x287/0x9e0 net/core/net_namespace.c:362
 copy_net_ns+0x33f/0x570 net/core/net_namespace.c:516
 create_new_namespaces+0x425/0x7b0 kernel/nsproxy.c:110
 unshare_nsproxy_namespaces+0x124/0x180 kernel/nsproxy.c:228
 ksys_unshare+0x57d/0xa70 kernel/fork.c:3333
 __do_sys_unshare kernel/fork.c:3404 [inline]
 __se_sys_unshare kernel/fork.c:3402 [inline]
 __x64_sys_unshare+0x38/0x40 kernel/fork.c:3402
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fe56b187527
RSP: 002b:00007fe56b49ffa8 EFLAGS: 00000206 ORIG_RAX: 0000000000000110
RAX: ffffffffffffffda RBX: 00007fe56b203389 RCX: 00007fe56b187527
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000040000000
RBP: 0000000000000000 R08: 00007fe56bea7d60 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000008
R13: 0000000000000003 R14: 0000000000000009 R15: 0000000000000000
 </TASK>
INFO: task syz-executor:11074 blocked for more than 143 seconds.
      Not tainted 6.13.0-rc3-syzkaller-00301-gbcde95ce32b6 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:25552 pid:11074 tgid:11074 ppid:1      flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5369 [inline]
 __schedule+0x1850/0x4c30 kernel/sched/core.c:6756
 __schedule_loop kernel/sched/core.c:6833 [inline]
 schedule+0x14b/0x320 kernel/sched/core.c:6848
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6905
 __mutex_lock_common kernel/locking/mutex.c:665 [inline]
 __mutex_lock+0x7e7/0xee0 kernel/locking/mutex.c:735
 register_nexthop_notifier+0x84/0x290 net/ipv4/nexthop.c:3878
 ops_init+0x31e/0x590 net/core/net_namespace.c:138
 setup_net+0x287/0x9e0 net/core/net_namespace.c:362
 copy_net_ns+0x33f/0x570 net/core/net_namespace.c:516
 create_new_namespaces+0x425/0x7b0 kernel/nsproxy.c:110
 unshare_nsproxy_namespaces+0x124/0x180 kernel/nsproxy.c:228
 ksys_unshare+0x57d/0xa70 kernel/fork.c:3333
 __do_sys_unshare kernel/fork.c:3404 [inline]
 __se_sys_unshare kernel/fork.c:3402 [inline]
 __x64_sys_unshare+0x38/0x40 kernel/fork.c:3402
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f71ff787527
RSP: 002b:00007f71ffa9ffa8 EFLAGS: 00000206 ORIG_RAX: 0000000000000110
RAX: ffffffffffffffda RBX: 00007f71ff803389 RCX: 00007f71ff787527
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000040000000
RBP: 0000000000000000 R08: 00007f72004a7d60 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000008
R13: 0000000000000003 R14: 0000000000000009 R15: 0000000000000000
 </TASK>
INFO: task syz-executor:11077 blocked for more than 143 seconds.
      Not tainted 6.13.0-rc3-syzkaller-00301-gbcde95ce32b6 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:26400 pid:11077 tgid:11077 ppid:1      flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5369 [inline]
 __schedule+0x1850/0x4c30 kernel/sched/core.c:6756
 __schedule_loop kernel/sched/core.c:6833 [inline]
 schedule+0x14b/0x320 kernel/sched/core.c:6848
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6905
 __mutex_lock_common kernel/locking/mutex.c:665 [inline]
 __mutex_lock+0x7e7/0xee0 kernel/locking/mutex.c:735
 register_nexthop_notifier+0x84/0x290 net/ipv4/nexthop.c:3878
 ops_init+0x31e/0x590 net/core/net_namespace.c:138
 setup_net+0x287/0x9e0 net/core/net_namespace.c:362
 copy_net_ns+0x33f/0x570 net/core/net_namespace.c:516
 create_new_namespaces+0x425/0x7b0 kernel/nsproxy.c:110
 unshare_nsproxy_namespaces+0x124/0x180 kernel/nsproxy.c:228
 ksys_unshare+0x57d/0xa70 kernel/fork.c:3333
 __do_sys_unshare kernel/fork.c:3404 [inline]
 __se_sys_unshare kernel/fork.c:3402 [inline]
 __x64_sys_unshare+0x38/0x40 kernel/fork.c:3402
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f1285387527
RSP: 002b:00007f128569ffa8 EFLAGS: 00000206 ORIG_RAX: 0000000000000110
RAX: ffffffffffffffda RBX: 00007f1285403389 RCX: 00007f1285387527
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000040000000
RBP: 0000000000000000 R08: 00007f12860a7d60 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000008
R13: 0000000000000003 R14: 0000000000000009 R15: 0000000000000000
 </TASK>
INFO: task syz-executor:11082 blocked for more than 143 seconds.
      Not tainted 6.13.0-rc3-syzkaller-00301-gbcde95ce32b6 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:25648 pid:11082 tgid:11082 ppid:1      flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5369 [inline]
 __schedule+0x1850/0x4c30 kernel/sched/core.c:6756
 __schedule_loop kernel/sched/core.c:6833 [inline]
 schedule+0x14b/0x320 kernel/sched/core.c:6848
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6905
 __mutex_lock_common kernel/locking/mutex.c:665 [inline]
 __mutex_lock+0x7e7/0xee0 kernel/locking/mutex.c:735
 register_nexthop_notifier+0x84/0x290 net/ipv4/nexthop.c:3878
 ops_init+0x31e/0x590 net/core/net_namespace.c:138
 setup_net+0x287/0x9e0 net/core/net_namespace.c:362
 copy_net_ns+0x33f/0x570 net/core/net_namespace.c:516
 create_new_namespaces+0x425/0x7b0 kernel/nsproxy.c:110
 unshare_nsproxy_namespaces+0x124/0x180 kernel/nsproxy.c:228
 ksys_unshare+0x57d/0xa70 kernel/fork.c:3333
 __do_sys_unshare kernel/fork.c:3404 [inline]
 __se_sys_unshare kernel/fork.c:3402 [inline]
 __x64_sys_unshare+0x38/0x40 kernel/fork.c:3402
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f45a1187527
RSP: 002b:00007f45a149ffa8 EFLAGS: 00000206 ORIG_RAX: 0000000000000110
RAX: ffffffffffffffda RBX: 00007f45a1203389 RCX: 00007f45a1187527
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000040000000
RBP: 0000000000000000 R08: 00007f45a1ea7d60 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000008
R13: 0000000000000003 R14: 0000000000000009 R15: 0000000000000000
 </TASK>

Showing all locks held in the system:
3 locks held by kworker/1:0/25:
1 lock held by khungtaskd/30:
 #0: ffffffff8e937ae0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline]
 #0: ffffffff8e937ae0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
 #0: ffffffff8e937ae0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6744
3 locks held by kworker/u8:7/1110:
 #0: ffff88801ac89148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline]
 #0: ffff88801ac89148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1840 kernel/workqueue.c:3310
 #1: ffffc90003f4fd00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline]
 #1: ffffc90003f4fd00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1840 kernel/workqueue.c:3310
 #2: ffffffff8fcb2c08 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:281
1 lock held by dhcpcd/5499:
 #0: ffffffff8fcb2c08 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:79 [inline]
 #0: ffffffff8fcb2c08 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:326 [inline]
 #0: ffffffff8fcb2c08 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0xce2/0x2210 net/core/rtnetlink.c:4011
2 locks held by getty/5592:
 #0: ffff8880319540a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
 #1: ffffc900032fb2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x6a6/0x1e00 drivers/tty/n_tty.c:2211
7 locks held by kworker/1:3/5853:
3 locks held by kworker/u8:24/6432:
 #0: ffff88814d8b1948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline]
 #0: ffff88814d8b1948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1840 kernel/workqueue.c:3310
 #1: ffffc9001b4afd00 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline]
 #1: ffffc9001b4afd00 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1840 kernel/workqueue.c:3310
 #2: ffffffff8fcb2c08 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_verify_work+0x19/0x30 net/ipv6/addrconf.c:4755
4 locks held by kworker/u8:26/6434:
 #0: ffff88801baed948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline]
 #0: ffff88801baed948 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1840 kernel/workqueue.c:3310
 #1: ffffc9001b4cfd00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline]
 #1: ffffc9001b4cfd00 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1840 kernel/workqueue.c:3310
 #2: ffffffff8fca6750 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0x16a/0xd50 net/core/net_namespace.c:602
 #3: ffffffff8fcb2c08 (rtnl_mutex){+.+.}-{4:4}, at: tc_action_net_exit include/net/act_api.h:173 [inline]
 #3: ffffffff8fcb2c08 (rtnl_mutex){+.+.}-{4:4}, at: gate_exit_net+0x30/0x100 net/sched/act_gate.c:654
7 locks held by syz-executor/10774:
 #0: ffff8880365a8420 (sb_writers#8){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2964 [inline]
 #0: ffff8880365a8420 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x225/0xd30 fs/read_write.c:675
 #1: ffff8880338ef888 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1ea/0x500 fs/kernfs/file.c:325
 #2: ffff888026c2b788 (kn->active#49){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x20e/0x500 fs/kernfs/file.c:326
 #3: ffffffff8f55e868 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xfc/0x480 drivers/net/netdevsim/bus.c:216
 #4: ffff88805db1f0e8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1014 [inline]
 #4: ffff88805db1f0e8 (&dev->mutex){....}-{4:4}, at: __device_driver_lock drivers/base/dd.c:1095 [inline]
 #4: ffff88805db1f0e8 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xce/0x7c0 drivers/base/dd.c:1293
 #5: ffff88807cb20250 (&devlink->lock_key#2){+.+.}-{4:4}, at: nsim_drv_remove+0x50/0x160 drivers/net/netdevsim/dev.c:1675
 #6: ffffffff8fcb2c08 (rtnl_mutex){+.+.}-{4:4}, at: unregister_netdevice_notifier_net+0x89/0x3a0 net/core/dev.c:1917
2 locks held by syz-executor/11029:
 #0: ffffffff8fca6750 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x328/0x570 net/core/net_namespace.c:512
 #1: ffffffff8fcb2c08 (rtnl_mutex){+.+.}-{4:4}, at: ip_tunnel_init_net+0x20e/0x720 net/ipv4/ip_tunnel.c:1159
2 locks held by syz-executor/11031:
 #0: ffffffff8fca6750 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x328/0x570 net/core/net_namespace.c:512
 #1: ffffffff8fcb2c08 (rtnl_mutex){+.+.}-{4:4}, at: wg_netns_pre_exit+0x1f/0x1e0 drivers/net/wireguard/device.c:415
2 locks held by syz-executor/11034:
 #0: ffffffff8fca6750 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x328/0x570 net/core/net_namespace.c:512
 #1: ffffffff8fcb2c08 (rtnl_mutex){+.+.}-{4:4}, at: wg_netns_pre_exit+0x1f/0x1e0 drivers/net/wireguard/device.c:415
2 locks held by syz-executor/11039:
 #0: ffffffff8fca6750 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x328/0x570 net/core/net_namespace.c:512
 #1: ffffffff8fcb2c08 (rtnl_mutex){+.+.}-{4:4}, at: wg_netns_pre_exit+0x1f/0x1e0 drivers/net/wireguard/device.c:415
2 locks held by syz-executor/11061:
 #0: ffffffff8fca6750 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x328/0x570 net/core/net_namespace.c:512
 #1: ffffffff8fcb2c08 (rtnl_mutex){+.+.}-{4:4}, at: ip_tunnel_init_net+0x20e/0x720 net/ipv4/ip_tunnel.c:1159
2 locks held by syz-executor/11070:
 #0: ffffffff8fca6750 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x328/0x570 net/core/net_namespace.c:512
 #1: ffffffff8fcb2c08 (rtnl_mutex){+.+.}-{4:4}, at: register_nexthop_notifier+0x84/0x290 net/ipv4/nexthop.c:3878
2 locks held by syz-executor/11074:
 #0: ffffffff8fca6750 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x328/0x570 net/core/net_namespace.c:512
 #1: ffffffff8fcb2c08 (rtnl_mutex){+.+.}-{4:4}, at: register_nexthop_notifier+0x84/0x290 net/ipv4/nexthop.c:3878
2 locks held by syz-executor/11077:
 #0: ffffffff8fca6750 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x328/0x570 net/core/net_namespace.c:512
 #1: ffffffff8fcb2c08 (rtnl_mutex){+.+.}-{4:4}, at: register_nexthop_notifier+0x84/0x290 net/ipv4/nexthop.c:3878
2 locks held by syz-executor/11082:
 #0: ffffffff8fca6750 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x328/0x570 net/core/net_namespace.c:512
 #1: ffffffff8fcb2c08 (rtnl_mutex){+.+.}-{4:4}, at: register_nexthop_notifier+0x84/0x290 net/ipv4/nexthop.c:3878
2 locks held by syz-executor/11086:
 #0: ffffffff8fca6750 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x328/0x570 net/core/net_namespace.c:512
 #1: ffffffff8fcb2c08 (rtnl_mutex){+.+.}-{4:4}, at: register_nexthop_notifier+0x84/0x290 net/ipv4/nexthop.c:3878
2 locks held by syz-executor/11117:
 #0: ffffffff8fca6750 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x328/0x570 net/core/net_namespace.c:512
 #1: ffffffff8fcb2c08 (rtnl_mutex){+.+.}-{4:4}, at: register_nexthop_notifier+0x84/0x290 net/ipv4/nexthop.c:3878
2 locks held by syz-executor/11120:
 #0: ffffffff8fca6750 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x328/0x570 net/core/net_namespace.c:512
 #1: ffffffff8fcb2c08 (rtnl_mutex){+.+.}-{4:4}, at: register_nexthop_notifier+0x84/0x290 net/ipv4/nexthop.c:3878
2 locks held by syz-executor/11123:
 #0: ffffffff8fca6750
 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x328/0x570 net/core/net_namespace.c:512
 #1: ffffffff8fcb2c08 (rtnl_mutex){+.+.}-{4:4}, at: register_nexthop_notifier+0x84/0x290 net/ipv4/nexthop.c:3878
2 locks held by syz-executor/11129:
 #0: ffffffff8fca6750 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x328/0x570 net/core/net_namespace.c:512
 #1: ffffffff8fcb2c08 (rtnl_mutex){+.+.}-{4:4}, at: register_nexthop_notifier+0x84/0x290 net/ipv4/nexthop.c:3878
2 locks held by syz-executor/11136:
 #0: ffffffff8fca6750 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x328/0x570 net/core/net_namespace.c:512
 #1: ffffffff8fcb2c08 (rtnl_mutex){+.+.}-{4:4}, at: register_nexthop_notifier+0x84/0x290 net/ipv4/nexthop.c:3878
2 locks held by syz-executor/11144:
 #0: ffffffff8fca6750 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x328/0x570 net/core/net_namespace.c:512
 #1: ffffffff8fcb2c08 (rtnl_mutex){+.+.}-{4:4}, at: register_nexthop_notifier+0x84/0x290 net/ipv4/nexthop.c:3878
2 locks held by syz-executor/11148:
 #0: ffffffff8fca6750 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x328/0x570 net/core/net_namespace.c:512
 #1: ffffffff8fcb2c08 (rtnl_mutex){+.+.}-{4:4}, at: register_nexthop_notifier+0x84/0x290 net/ipv4/nexthop.c:3878
2 locks held by syz-executor/11151:
 #0: ffffffff8fca6750 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x328/0x570 net/core/net_namespace.c:512
 #1: ffffffff8fcb2c08 (rtnl_mutex){+.+.}-{4:4}, at: register_nexthop_notifier+0x84/0x290 net/ipv4/nexthop.c:3878
2 locks held by syz-executor/11156:
 #0: ffffffff8fca6750 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x328/0x570 net/core/net_namespace.c:512
 #1: ffffffff8fcb2c08 (rtnl_mutex){+.+.}-{4:4}, at: register_nexthop_notifier+0x84/0x290 net/ipv4/nexthop.c:3878
2 locks held by syz-executor/11164:
 #0: ffffffff8fca6750 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x328/0x570 net/core/net_namespace.c:512
 #1: ffffffff8fcb2c08 (rtnl_mutex){+.+.}-{4:4}, at: register_nexthop_notifier+0x84/0x290 net/ipv4/nexthop.c:3878

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

NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.13.0-rc3-syzkaller-00301-gbcde95ce32b6 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
 nmi_cpu_backtrace+0x49c/0x4d0 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:234 [inline]
 watchdog+0xff6/0x1040 kernel/hung_task.c:397
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 5853 Comm: kworker/1:3 Not tainted 6.13.0-rc3-syzkaller-00301-gbcde95ce32b6 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Workqueue: events legacy_dvb_usb_read_remote_control
RIP: 0010:__preempt_count_add arch/x86/include/asm/preempt.h:79 [inline]
RIP: 0010:rcu_is_watching+0x9/0xb0 kernel/rcu/tree.c:736
Code: 03 eb cd 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 41 57 41 56 53 <65> ff 05 a8 c6 7e 7e e8 3b b8 43 0a 89 c3 83 f8 08 73 7a 49 bf 00
RSP: 0018:ffffc90000a17a20 EFLAGS: 00000057
RAX: 0000000000000001 RBX: 0000000000000001 RCX: ffffffff81a72d3c
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff90197df0
RBP: ffffc90000a17b10 R08: ffffffff90197df7 R09: 1ffffffff2032fbe
R10: dffffc0000000000 R11: fffffbfff2032fbf R12: dffffc0000000000
R13: 1ffff92000142f54 R14: ffffc90000a17aa0 R15: 0000000000000200
FS:  0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f29827ffe4c CR3: 000000000e736000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 trace_irq_enable+0x3b/0x120 include/trace/events/preemptirq.h:40
 trace_hardirqs_on+0x18/0x40 kernel/trace/trace_preemptirq.c:73
 __local_bh_enable_ip+0x168/0x200 kernel/softirq.c:394
 local_bh_enable include/linux/bottom_half.h:33 [inline]
 ipt_do_table+0x1552/0x1860 net/ipv4/netfilter/ip_tables.c:357
 ipt_mangle_out net/ipv4/netfilter/iptable_mangle.c:53 [inline]
 iptable_mangle_hook+0x154/0x4b0 net/ipv4/netfilter/iptable_mangle.c:79
 nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline]
 nf_hook_slow+0xc3/0x220 net/netfilter/core.c:626
 nf_hook+0x2c4/0x450 include/linux/netfilter.h:269
 __ip_local_out+0x3d9/0x4e0 net/ipv4/ip_output.c:119
 ip_local_out+0x26/0x70 net/ipv4/ip_output.c:128
 synproxy_send_client_synack+0x8a4/0xe20 net/netfilter/nf_synproxy_core.c:484
 nft_synproxy_eval_v4+0x3ca/0x610 net/netfilter/nft_synproxy.c:59
 nft_synproxy_do_eval+0x362/0xa60 net/netfilter/nft_synproxy.c:141
 expr_call_ops_eval net/netfilter/nf_tables_core.c:240 [inline]
 nft_do_chain+0x4ad/0x1da0 net/netfilter/nf_tables_core.c:288
 nft_do_chain_inet+0x418/0x6b0 net/netfilter/nft_chain_filter.c:161
 nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline]
 nf_hook_slow+0xc3/0x220 net/netfilter/core.c:626
 nf_hook include/linux/netfilter.h:269 [inline]
 NF_HOOK+0x29e/0x450 include/linux/netfilter.h:312
 NF_HOOK+0x3a4/0x450 include/linux/netfilter.h:314
 __netif_receive_skb_one_core net/core/dev.c:5672 [inline]
 __netif_receive_skb+0x2bf/0x650 net/core/dev.c:5785
 process_backlog+0x662/0x15b0 net/core/dev.c:6117
 __napi_poll+0xcb/0x490 net/core/dev.c:6883
 napi_poll net/core/dev.c:6952 [inline]
 net_rx_action+0x89b/0x1240 net/core/dev.c:7074
 handle_softirqs+0x2d4/0x9b0 kernel/softirq.c:561
 __do_softirq kernel/softirq.c:595 [inline]
 invoke_softirq kernel/softirq.c:435 [inline]
 __irq_exit_rcu+0xf7/0x220 kernel/softirq.c:662
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:678
 instr_sysvec_call_function_single arch/x86/kernel/smp.c:266 [inline]
 sysvec_call_function_single+0xa3/0xc0 arch/x86/kernel/smp.c:266
 </IRQ>
 <TASK>
 asm_sysvec_call_function_single+0x1a/0x20 arch/x86/include/asm/idtentry.h:709
RIP: 0010:console_flush_all+0x996/0xeb0
Code: 48 21 c3 0f 85 16 02 00 00 e8 f6 ad 20 00 4c 8b 7c 24 10 4d 85 f6 75 07 e8 e7 ad 20 00 eb 06 e8 e0 ad 20 00 fb 48 8b 5c 24 18 <48> 8b 44 24 30 42 80 3c 28 00 74 08 48 89 df e8 76 15 87 00 4c 8b
RSP: 0018:ffffc9000406f5e0 EFLAGS: 00000293
RAX: ffffffff817ec650 RBX: ffffffff8f175058 RCX: ffff888035a68000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc9000406f790 R08: ffffffff817ec627 R09: 1ffffffff2854910
R10: dffffc0000000000 R11: fffffbfff2854911 R12: ffffffff8f175000
R13: dffffc0000000000 R14: 0000000000000200 R15: ffffc9000406f7e0
 __console_flush_and_unlock kernel/printk/printk.c:3269 [inline]
 console_unlock+0x14f/0x3b0 kernel/printk/printk.c:3309
 vprintk_emit+0x730/0xa10 kernel/printk/printk.c:2432
 _printk+0xd5/0x120 kernel/printk/printk.c:2457
 m920x_rc_query+0x314/0x820
 legacy_dvb_usb_read_remote_control+0x122/0x590 drivers/media/usb/dvb-usb/dvb-usb-remote.c:123
 process_one_work kernel/workqueue.c:3229 [inline]
 process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3310
 worker_thread+0x870/0xd30 kernel/workqueue.c:3391
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>

Crashes (5):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/12/22 23:32 upstream bcde95ce32b6 b4fbdbd4 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce INFO: task hung in register_nexthop_notifier
2024/12/11 14:30 upstream f92f4749861b ff949d25 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-386 INFO: task hung in register_nexthop_notifier
2024/11/21 11:15 net 66418447d27b 4b25d554 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in register_nexthop_notifier
2025/02/25 10:07 net-next 98f992884333 d34966d1 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in register_nexthop_notifier
2024/12/16 22:30 net-next bc6a5efe3dcd f93b2b55 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in register_nexthop_notifier
* Struck through repros no longer work on HEAD.