syzbot

INFO: task syz.3.1876:15966 blocked for more than 143 seconds.
      Not tainted 6.12.0-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.1876      state:D stack:27248 pid:15966 tgid:15965 ppid:15004  flags:0x00000004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5328 [inline]
 __schedule+0xe55/0x5740 kernel/sched/core.c:6693
 __schedule_loop kernel/sched/core.c:6770 [inline]
 schedule+0xe7/0x350 kernel/sched/core.c:6785
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6842
 __mutex_lock_common kernel/locking/mutex.c:684 [inline]
 __mutex_lock+0x5b8/0x9c0 kernel/locking/mutex.c:752
 nfsd_nl_listener_get_doit+0x139/0x710 fs/nfsd/nfsctl.c:2121
 genl_family_rcv_msg_doit+0x202/0x2f0 net/netlink/genetlink.c:1115
 genl_family_rcv_msg net/netlink/genetlink.c:1195 [inline]
 genl_rcv_msg+0x565/0x800 net/netlink/genetlink.c:1210
 netlink_rcv_skb+0x165/0x410 net/netlink/af_netlink.c:2536
 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219
 netlink_unicast_kernel net/netlink/af_netlink.c:1316 [inline]
 netlink_unicast+0x53c/0x7f0 net/netlink/af_netlink.c:1342
 netlink_sendmsg+0x8b8/0xd70 net/netlink/af_netlink.c:1886
 sock_sendmsg_nosec net/socket.c:729 [inline]
 __sock_sendmsg net/socket.c:744 [inline]
 ____sys_sendmsg+0x9ae/0xb40 net/socket.c:2607
 ___sys_sendmsg+0x135/0x1e0 net/socket.c:2661
 __sys_sendmsg+0x117/0x1f0 net/socket.c:2690
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa19b77e719
RSP: 002b:00007fa19c4dc038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007fa19b935f80 RCX: 00007fa19b77e719
RDX: 0000000000008000 RSI: 0000000020000bc0 RDI: 0000000000000003
RBP: 00007fa19b7f175e R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fa19b935f80 R15: 00007fffd9bb7d58
 </TASK>

Showing all locks held in the system:
4 locks held by kworker/u8:1/12:
 #0: ffff88801baed948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x1212/0x1b30 kernel/workqueue.c:3204
 #1: ffffc90000117d80 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x8bb/0x1b30 kernel/workqueue.c:3205
 #2: ffffffff8faafc10 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0xbb/0xb40 net/core/net_namespace.c:580
 #3: ffffffff8ddc3178 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock+0x282/0x3b0 kernel/rcu/tree_exp.h:297
1 lock held by khungtaskd/30:
 #0: ffffffff8ddb7880 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline]
 #0: ffffffff8ddb7880 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
 #0: ffffffff8ddb7880 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x7f/0x390 kernel/locking/lockdep.c:6720
1 lock held by klogd/5204:
2 locks held by getty/5598:
 #0: ffff88814daf70a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
 #1: ffffc90002f062f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xfba/0x1480 drivers/tty/n_tty.c:2211
2 locks held by syz-executor/13084:
 #0: ffff888011dec0e0 (&type->s_umount_key#49){++++}-{3:3}, at: __super_lock fs/super.c:56 [inline]
 #0: ffff888011dec0e0 (&type->s_umount_key#49){++++}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline]
 #0: ffff888011dec0e0 (&type->s_umount_key#49){++++}-{3:3}, at: deactivate_super+0xd6/0x100 fs/super.c:505
 #1: ffffffff8e1d1ec8 (nfsd_mutex){+.+.}-{3:3}, at: nfsd_shutdown_threads+0x5b/0xf0 fs/nfsd/nfssvc.c:625
2 locks held by syz.4.1781/15553:
 #0: ffffffff8fb63890 (cb_lock){++++}-{3:3}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
 #1: ffffffff8e1d1ec8 (nfsd_mutex){+.+.}-{3:3}, at: nfsd_nl_threads_set_doit+0x694/0xbe0 fs/nfsd/nfsctl.c:1671
2 locks held by syz-executor/15839:
 #0: ffff88802f4760e0 (&type->s_umount_key#49){++++}-{3:3}, at: __super_lock fs/super.c:56 [inline]
 #0: ffff88802f4760e0 (&type->s_umount_key#49){++++}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline]
 #0: ffff88802f4760e0 (&type->s_umount_key#49){++++}-{3:3}, at: deactivate_super+0xd6/0x100 fs/super.c:505
 #1: ffffffff8e1d1ec8 (nfsd_mutex){+.+.}-{3:3}, at: nfsd_shutdown_threads+0x5b/0xf0 fs/nfsd/nfssvc.c:625
2 locks held by syz.3.1876/15966:
 #0: ffffffff8fb63890 (cb_lock){++++}-{3:3}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
 #1: ffffffff8e1d1ec8 (nfsd_mutex){+.+.}-{3:3}, at: nfsd_nl_listener_get_doit+0x139/0x710 fs/nfsd/nfsctl.c:2121
2 locks held by syz.7.1917/16255:
 #0: ffffffff8fb63890 (cb_lock){++++}-{3:3}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
 #1: ffffffff8e1d1ec8 (nfsd_mutex){+.+.}-{3:3}, at: nfsd_nl_threads_set_doit+0x694/0xbe0 fs/nfsd/nfsctl.c:1671
2 locks held by syz-executor/16331:
 #0: ffff88807f9080e0 (&type->s_umount_key#49){++++}-{3:3}, at: __super_lock fs/super.c:56 [inline]
 #0: ffff88807f9080e0 (&type->s_umount_key#49){++++}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline]
 #0: ffff88807f9080e0 (&type->s_umount_key#49){++++}-{3:3}, at: deactivate_super+0xd6/0x100 fs/super.c:505
 #1: ffffffff8e1d1ec8 (nfsd_mutex){+.+.}-{3:3}, at: nfsd_shutdown_threads+0x5b/0xf0 fs/nfsd/nfssvc.c:625
2 locks held by syz.1.1955/16652:
 #0: ffffffff8fb63890 (cb_lock){++++}-{3:3}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
 #1: ffffffff8e1d1ec8 (nfsd_mutex){+.+.}-{3:3}, at: nfsd_nl_threads_set_doit+0x694/0xbe0 fs/nfsd/nfsctl.c:1671
2 locks held by syz-executor/16666:
 #0: ffff8880223380e0 (&type->s_umount_key#49){++++}-{3:3}, at: __super_lock fs/super.c:56 [inline]
 #0: ffff8880223380e0 (&type->s_umount_key#49){++++}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline]
 #0: ffff8880223380e0 (&type->s_umount_key#49){++++}-{3:3}, at: deactivate_super+0xd6/0x100 fs/super.c:505
 #1: ffffffff8e1d1ec8 (nfsd_mutex){+.+.}-{3:3}, at: nfsd_shutdown_threads+0x5b/0xf0 fs/nfsd/nfssvc.c:625
2 locks held by syz.2.1977/16899:
 #0: ffffffff8fb63890 (cb_lock){++++}-{3:3}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
 #1: ffffffff8e1d1ec8 (nfsd_mutex){+.+.}-{3:3}, at: nfsd_nl_threads_set_doit+0x694/0xbe0 fs/nfsd/nfsctl.c:1671
2 locks held by syz-executor/17407:
 #0: ffff88806f4920e0 (&type->s_umount_key#49){++++}-{3:3}, at: __super_lock fs/super.c:56 [inline]
 #0: ffff88806f4920e0 (&type->s_umount_key#49){++++}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline]
 #0: ffff88806f4920e0 (&type->s_umount_key#49){++++}-{3:3}, at: deactivate_super+0xd6/0x100 fs/super.c:505
 #1: ffffffff8e1d1ec8 (nfsd_mutex){+.+.}-{3:3}, at: nfsd_shutdown_threads+0x5b/0xf0 fs/nfsd/nfssvc.c:625
2 locks held by syz.9.2071/18238:
 #0: ffff88809e6260e0 (&type->s_umount_key#49){++++}-{3:3}, at: __super_lock fs/super.c:56 [inline]
 #0: ffff88809e6260e0 (&type->s_umount_key#49){++++}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline]
 #0: ffff88809e6260e0 (&type->s_umount_key#49){++++}-{3:3}, at: deactivate_super+0xd6/0x100 fs/super.c:505
 #1: ffffffff8e1d1ec8 (nfsd_mutex){+.+.}-{3:3}, at: nfsd_shutdown_threads+0x5b/0xf0 fs/nfsd/nfssvc.c:625
2 locks held by syz.0.2107/18573:
 #0: ffff88806f44c0e0 (&type->s_umount_key#49){++++}-{3:3}, at: __super_lock fs/super.c:56 [inline]
 #0: ffff88806f44c0e0 (&type->s_umount_key#49){++++}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline]
 #0: ffff88806f44c0e0 (&type->s_umount_key#49){++++}-{3:3}, at: deactivate_super+0xd6/0x100 fs/super.c:505
 #1: ffffffff8e1d1ec8 (nfsd_mutex){+.+.}-{3:3}, at: nfsd_shutdown_threads+0x5b/0xf0 fs/nfsd/nfssvc.c:625
2 locks held by syz-executor/18686:
 #0: ffff88804accc0e0 (&type->s_umount_key#49){++++}-{3:3}, at: __super_lock fs/super.c:56 [inline]
 #0: ffff88804accc0e0 (&type->s_umount_key#49){++++}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline]
 #0: ffff88804accc0e0 (&type->s_umount_key#49){++++}-{3:3}, at: deactivate_super+0xd6/0x100 fs/super.c:505
 #1: ffffffff8e1d1ec8 (nfsd_mutex){+.+.}-{3:3}, at: nfsd_shutdown_threads+0x5b/0xf0 fs/nfsd/nfssvc.c:625
2 locks held by syz.4.2138/18871:
 #0: ffff88808deb40e0 (&type->s_umount_key#49){++++}-{3:3}, at: __super_lock fs/super.c:56 [inline]
 #0: ffff88808deb40e0 (&type->s_umount_key#49){++++}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline]
 #0: ffff88808deb40e0 (&type->s_umount_key#49){++++}-{3:3}, at: deactivate_super+0xd6/0x100 fs/super.c:505
 #1: ffffffff8e1d1ec8 (nfsd_mutex){+.+.}-{3:3}, at: nfsd_shutdown_threads+0x5b/0xf0 fs/nfsd/nfssvc.c:625
2 locks held by syz.7.2150/19085:
 #0: ffff8880996fa0e0 (&type->s_umount_key#49){++++}-{3:3}, at: __super_lock fs/super.c:56 [inline]
 #0: ffff8880996fa0e0 (&type->s_umount_key#49){++++}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline]
 #0: ffff8880996fa0e0 (&type->s_umount_key#49){++++}-{3:3}, at: deactivate_super+0xd6/0x100 fs/super.c:505
 #1: ffffffff8e1d1ec8 (nfsd_mutex){+.+.}-{3:3}, at: nfsd_shutdown_threads+0x5b/0xf0 fs/nfsd/nfssvc.c:625
1 lock held by syz.6.2226/19441:
 #0: ffffffff8ddc3178 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock+0x1a4/0x3b0 kernel/rcu/tree_exp.h:329
1 lock held by syz.5.2229/19455:
 #0: ffffffff8ddc3178 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock+0x1a4/0x3b0 kernel/rcu/tree_exp.h:329

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

NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.12.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
 nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x29c/0x300 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:223 [inline]
 watchdog+0xf0c/0x1240 kernel/hung_task.c:379
 kthread+0x2c1/0x3a0 kernel/kthread.c:389
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 19455 Comm: syz.5.2229 Not tainted 6.12.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
RIP: 0010:kasan_check_range+0x1a/0x1a0 mm/kasan/generic.c:188
Code: 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 66 0f 1f 00 48 85 f6 0f 84 50 01 00 00 48 89 f8 41 54 44 0f b6 c2 48 01 f0 55 <53> 0f 82 c6 00 00 00 48 b8 ff ff ff ff ff 7f ff ff 48 39 f8 0f 83
RSP: 0018:ffffc900034bf880 EFLAGS: 00000292
RAX: ffffffff901cf810 RBX: 1ffff92000697f15 RCX: ffffffff816a2fb9
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff901cf808
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: ffffffff8ddb7880
R13: 0000000000000001 R14: 000000000003dc0c R15: ffff888020435ca8
FS:  0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000ef0000 CR3: 000000000db7c000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <TASK>
 instrument_atomic_read include/linux/instrumented.h:68 [inline]
 _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline]
 cpumask_test_cpu include/linux/cpumask.h:570 [inline]
 cpu_online include/linux/cpumask.h:1117 [inline]
 trace_lock_release include/trace/events/lock.h:69 [inline]
 lock_release+0xa9/0x6f0 kernel/locking/lockdep.c:5836
 rcu_lock_release include/linux/rcupdate.h:347 [inline]
 rcu_read_unlock include/linux/rcupdate.h:880 [inline]
 page_ext_put+0x43/0xd0 mm/page_ext.c:550
 __reset_page_owner+0x28d/0x400 mm/page_owner.c:300
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1127 [inline]
 free_unref_page+0x661/0x1080 mm/page_alloc.c:2657
 vfree+0x17a/0x890 mm/vmalloc.c:3361
 kcov_put kernel/kcov.c:439 [inline]
 kcov_put+0x2a/0x40 kernel/kcov.c:435
 kcov_close+0xd/0x20 kernel/kcov.c:535
 __fput+0x3f6/0xb60 fs/file_table.c:431
 task_work_run+0x14e/0x250 kernel/task_work.c:239
 exit_task_work include/linux/task_work.h:43 [inline]
 do_exit+0xadd/0x2d70 kernel/exit.c:939
 do_group_exit+0xd3/0x2a0 kernel/exit.c:1088
 get_signal+0x2658/0x26d0 kernel/signal.c:2918
 arch_do_signal_or_restart+0x90/0x7e0 arch/x86/kernel/signal.c:337
 exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0x150/0x2a0 kernel/entry/common.c:218
 do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fe31697e719
Code: Unable to access opcode bytes at 0x7fe31697e6ef.
RSP: 002b:00007fe3177d6038 EFLAGS: 00000246 ORIG_RAX: 000000000000001c
RAX: ffffffffffffffea RBX: 00007fe316b36058 RCX: 00007fe31697e719
RDX: 0000000000000015 RSI: ffffffffffff0001 RDI: 0000000000000000
RBP: 00007fe3169f175e R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fe316b36058 R15: 00007ffeb35030d8
 </TASK>