INFO: task syz.5.1664:12747 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.5.1664 state:D stack:26648 pid:12747 tgid:12744 ppid:12384 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x14bc/0x5000 kernel/sched/core.c:6863
__schedule_loop kernel/sched/core.c:6945 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6960
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7017
__mutex_lock_common kernel/locking/mutex.c:692 [inline]
__mutex_lock+0x7e6/0x1350 kernel/locking/mutex.c:776
nfsd_nl_listener_set_doit+0x137/0x1660 fs/nfsd/nfsctl.c:1880
genl_family_rcv_msg_doit+0x215/0x300 net/netlink/genetlink.c:1115
genl_family_rcv_msg net/netlink/genetlink.c:1195 [inline]
genl_rcv_msg+0x60e/0x790 net/netlink/genetlink.c:1210
netlink_rcv_skb+0x208/0x470 net/netlink/af_netlink.c:2550
genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219
netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
netlink_unicast+0x82f/0x9e0 net/netlink/af_netlink.c:1344
netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1894
sock_sendmsg_nosec net/socket.c:718 [inline]
__sock_sendmsg+0x21c/0x270 net/socket.c:733
____sys_sendmsg+0x505/0x820 net/socket.c:2608
___sys_sendmsg+0x21f/0x2a0 net/socket.c:2662
__sys_sendmsg net/socket.c:2694 [inline]
__do_sys_sendmsg net/socket.c:2699 [inline]
__se_sys_sendmsg net/socket.c:2697 [inline]
__x64_sys_sendmsg+0x19b/0x260 net/socket.c:2697
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f1c6938f749
RSP: 002b:00007f1c6a2b2038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f1c695e6090 RCX: 00007f1c6938f749
RDX: 0000000004008090 RSI: 0000200000000140 RDI: 0000000000000003
RBP: 00007f1c69413f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f1c695e6128 R14: 00007f1c695e6090 R15: 00007fffa69fed38
Showing all locks held in the system:
3 locks held by kworker/u8:1/13:
#0: ffff88801a069948 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline]
#0: ffff88801a069948 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x1770 kernel/workqueue.c:3340
#1: ffffc90000127b80 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline]
#1: ffffc90000127b80 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x1770 kernel/workqueue.c:3340
#2: ffffffff8f2f55c8 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:303
1 lock held by khungtaskd/32:
#0: ffffffff8df41cc0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8df41cc0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8df41cc0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
3 locks held by kworker/u8:11/1331:
#0: ffff88814cc4b948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline]
#0: ffff88814cc4b948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x1770 kernel/workqueue.c:3340
#1: ffffc900046cfb80 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline]
#1: ffffc900046cfb80 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x1770 kernel/workqueue.c:3340
#2: ffffffff8f2f55c8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#2: ffffffff8f2f55c8 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x112/0x14b0 net/ipv6/addrconf.c:4194
2 locks held by getty/5594:
#0: ffff88814c6480a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
2 locks held by kworker/1:7/5975:
1 lock held by udevd/10728:
#0: ffff888142fea358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30 block/bdev.c:962
3 locks held by syz.2.1435/11882:
#0: ffffffff8f35d170 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffffffff8e233a08 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0x137/0x1660 fs/nfsd/nfsctl.c:1880
#2: ffffffff8df477f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline]
#2: ffffffff8df477f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b9/0x730 kernel/rcu/tree_exp.h:956
2 locks held by syz.5.1664/12747:
#0: ffffffff8f35d170 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffffffff8e233a08 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0x137/0x1660 fs/nfsd/nfsctl.c:1880
2 locks held by syz.6.2691/16653:
#0: ffffffff8f35d170 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffffffff8e233a08 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_threads_set_doit+0x2cb/0x960 fs/nfsd/nfsctl.c:1590
1 lock held by syz-executor/17389:
#0: ffffffff8f2f55c8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#0: ffffffff8f2f55c8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
#0: ffffffff8f2f55c8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8ec/0x1c90 net/core/rtnetlink.c:4071
3 locks held by syz.7.2913/17546:
#0: ffffffff8f2e8510 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x3cc/0x570 net/core/net_namespace.c:577
#1: ffffffff8f2f55c8 (rtnl_mutex){+.+.}-{4:4}, at: default_device_exit_batch+0xdc/0x9e0 net/core/dev.c:13022
#2: ffffffff8df477f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline]
#2: ffffffff8df477f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f6/0x730 kernel/rcu/tree_exp.h:956
5 locks held by syz.8.2917/17576:
#0: ffffffff8f2e8510 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x3cc/0x570 net/core/net_namespace.c:577
#1: ffffffff8f05dff0 (devices_rwsem){++++}-{4:4}, at: rdma_dev_init_net+0x19a/0x270 drivers/infiniband/core/device.c:1215
#2: ffffffff8f05e1b0 (rdma_nets_rwsem){++++}-{4:4}, at: rdma_dev_init_net+0x1d2/0x270 drivers/infiniband/core/device.c:1220
#3: ffff88801dbacf98 (&device->compat_devs_mutex){+.+.}-{4:4}, at: add_one_compat_dev+0xee/0x5c0 drivers/infiniband/core/device.c:979
#4: ffffffff8f2f55c8 (rtnl_mutex){+.+.}-{4:4}, at: ib_get_eth_speed+0x151/0x7b0 drivers/infiniband/core/verbs.c:1995
1 lock held by syz.1.2924/17595:
#0: ffffffff8f2f55c8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#0: ffffffff8f2f55c8 (rtnl_mutex){+.+.}-{4:4}, at: rtnetlink_rcv_msg+0x71c/0xb70 net/core/rtnetlink.c:6964
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 32 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:332 [inline]
watchdog+0xf3c/0xf80 kernel/hung_task.c:495
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 17389 Comm: syz-executor Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:rcu_is_watching_curr_cpu include/linux/context_tracking.h:128 [inline]
RIP: 0010:rcu_is_watching+0x3a/0xb0 kernel/rcu/tree.c:751
Code: e8 9b 18 a2 09 89 c3 83 f8 08 73 65 49 bf 00 00 00 00 00 fc ff df 4c 8d 34 dd d0 bd 98 8d 4c 89 f0 48 c1 e8 03 42 80 3c 38 00 <74> 08 4c 89 f7 e8 1c e9 7f 00 48 c7 c3 98 25 78 92 49 03 1e 48 89
RSP: 0018:ffffc90000a08378 EFLAGS: 00000246
RAX: 1ffffffff1b317bb RBX: 0000000000000001 RCX: 205f45b0292e9e00
RDX: 00000000a42637f2 RSI: ffffffff8bbfc640 RDI: ffffffff8bbfc600
RBP: dffffc0000000000 R08: ffffffff8173ef25 R09: ffffffff8df41cc0
R10: ffffc90000a084b8 R11: ffffffff81ad4ad0 R12: 1ffff9200014108d
R13: ffffc90000a084a0 R14: ffffffff8d98bdd8 R15: dffffc0000000000
FS: 000055556fd90500(0000) GS:ffff8881261b1000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f7465be2f98 CR3: 00000000799ce000 CR4: 00000000003526f0
Call Trace:
rcu_read_lock include/linux/rcupdate.h:868 [inline]
class_rcu_constructor include/linux/rcupdate.h:1195 [inline]
unwind_next_frame+0xd4/0x2390 arch/x86/kernel/unwind_orc.c:479
arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:56 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:77
unpoison_slab_object mm/kasan/common.c:342 [inline]
__kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:368
kasan_slab_alloc include/linux/kasan.h:252 [inline]
slab_post_alloc_hook mm/slub.c:4948 [inline]
slab_alloc_node mm/slub.c:5258 [inline]
kmem_cache_alloc_node_noprof+0x433/0x710 mm/slub.c:5310
__alloc_skb+0x255/0x430 net/core/skbuff.c:679
__netdev_alloc_skb+0x108/0x960 net/core/skbuff.c:754
netdev_alloc_skb include/linux/skbuff.h:3484 [inline]
dev_alloc_skb include/linux/skbuff.h:3497 [inline]
__ieee80211_beacon_get+0xc06/0x1880 net/mac80211/tx.c:5654
ieee80211_beacon_get_tim+0xb4/0x2b0 net/mac80211/tx.c:5776
ieee80211_beacon_get include/net/mac80211.h:5669 [inline]
mac80211_hwsim_beacon_tx+0x3c5/0x870 drivers/net/wireless/virtual/mac80211_hwsim.c:2361
__iterate_interfaces+0x2ab/0x590 net/mac80211/util.c:761
ieee80211_iterate_active_interfaces_atomic+0xdb/0x180 net/mac80211/util.c:797
mac80211_hwsim_beacon+0xbb/0x180 drivers/net/wireless/virtual/mac80211_hwsim.c:2395
__run_hrtimer kernel/time/hrtimer.c:1777 [inline]
__hrtimer_run_queues+0x51c/0xc30 kernel/time/hrtimer.c:1841
hrtimer_run_softirq+0x187/0x2b0 kernel/time/hrtimer.c:1858
handle_softirqs+0x27d/0x850 kernel/softirq.c:622
__do_softirq kernel/softirq.c:656 [inline]
invoke_softirq kernel/softirq.c:496 [inline]
__irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:723
irq_exit_rcu+0x9/0x30 kernel/softirq.c:739
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1056
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:get_current arch/x86/include/asm/current.h:25 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x8/0x70 kernel/kcov.c:216
Code: 8b 3d b4 7b d7 0b 48 89 de 5b e9 13 d2 5a 00 cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 48 8b 04 24 <65> 48 8b 0c 25 08 f0 76 92 65 8b 15 b8 a5 b5 10 81 e2 00 01 ff 00
RSP: 0018:ffffc900045cee58 EFLAGS: 00000a02
RAX: ffffffff84c2ff0a RBX: dffffc0000000000 RCX: ffff888020355b80
RDX: 0000000000000820 RSI: 0000000000000000 RDI: ffff888079dcc618
RBP: ffffc900045cef90 R08: ffff888079dcc613 R09: 1ffff1100f3b98c2
R10: dffffc0000000000 R11: ffffed100f3b98c3 R12: ffff888079dcc618
R13: 1ffff920008b9dd0 R14: 0000000000000820 R15: 0000000000000000
ref_tracker_alloc+0x7a/0x460 lib/ref_tracker.c:256
__netdev_tracker_alloc include/linux/netdevice.h:4399 [inline]
netdev_hold include/linux/netdevice.h:4428 [inline]
dev_hold include/linux/netdevice.h:4450 [inline]
dev_get_by_index+0x209/0x2e0 net/core/dev.c:983
netdev_get_by_index+0x25/0xb0 net/core/dev.c:1006
fib6_nh_init+0x1cd/0x1ff0 net/ipv6/route.c:3590
ip6_route_info_create_nh+0x16a/0xab0 net/ipv6/route.c:3890
ip6_route_add+0x6e/0x1b0 net/ipv6/route.c:3942
addrconf_prefix_route net/ipv6/addrconf.c:2488 [inline]
inet6_addr_add+0x75f/0xce0 net/ipv6/addrconf.c:3053
inet6_rtm_newaddr+0x93d/0xd20 net/ipv6/addrconf.c:5059
rtnetlink_rcv_msg+0x7cf/0xb70 net/core/rtnetlink.c:6958
netlink_rcv_skb+0x208/0x470 net/netlink/af_netlink.c:2550
netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
netlink_unicast+0x82f/0x9e0 net/netlink/af_netlink.c:1344
netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1894
sock_sendmsg_nosec net/socket.c:718 [inline]
__sock_sendmsg+0x21c/0x270 net/socket.c:733
__sys_sendto+0x3bd/0x520 net/socket.c:2222
__do_sys_sendto net/socket.c:2229 [inline]
__se_sys_sendto net/socket.c:2225 [inline]
__x64_sys_sendto+0xde/0x100 net/socket.c:2225
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd5961915dc
Code: 2a 5f 02 00 44 8b 4c 24 2c 4c 8b 44 24 20 89 c5 44 8b 54 24 28 48 8b 54 24 18 b8 2c 00 00 00 48 8b 74 24 10 8b 7c 24 08 0f 05 <48> 3d 00 f0 ff ff 77 34 89 ef 48 89 44 24 08 e8 70 5f 02 00 48 8b
RSP: 002b:00007ffc38d68880 EFLAGS: 00000293 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007fd596f14620 RCX: 00007fd5961915dc
RDX: 0000000000000040 RSI: 00007fd596f14670 RDI: 0000000000000003
RBP: 0000000000000000 R08: 00007ffc38d688d4 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000003
R13: 0000000000000000 R14: 00007fd596f14670 R15: 0000000000000000