INFO: task syz.5.12142:18320 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.5.12142 state:D stack:26120 pid:18320 tgid:18319 ppid:14270 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5298 [inline]
__schedule+0x15dd/0x52d0 kernel/sched/core.c:6911
__schedule_loop kernel/sched/core.c:6993 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7008
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7065
__mutex_lock_common kernel/locking/mutex.c:692 [inline]
__mutex_lock+0x7fe/0x1300 kernel/locking/mutex.c:776
nfsd_nl_version_get_doit+0x17c/0xc40 fs/nfsd/nfsctl.c:1828
genl_family_rcv_msg_doit+0x22a/0x330 net/netlink/genetlink.c:1114
genl_family_rcv_msg net/netlink/genetlink.c:1194 [inline]
genl_rcv_msg+0x61c/0x7a0 net/netlink/genetlink.c:1209
netlink_rcv_skb+0x232/0x4b0 net/netlink/af_netlink.c:2550
genl_rcv+0x28/0x40 net/netlink/genetlink.c:1218
netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
netlink_unicast+0x80f/0x9b0 net/netlink/af_netlink.c:1344
netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1894
sock_sendmsg_nosec net/socket.c:727 [inline]
__sock_sendmsg net/socket.c:742 [inline]
____sys_sendmsg+0x972/0x9f0 net/socket.c:2592
___sys_sendmsg+0x2a5/0x360 net/socket.c:2646
__sys_sendmsg net/socket.c:2678 [inline]
__do_sys_sendmsg net/socket.c:2683 [inline]
__se_sys_sendmsg net/socket.c:2681 [inline]
__x64_sys_sendmsg+0x1bd/0x2a0 net/socket.c:2681
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f3c5c99c819
RSP: 002b:00007f3c5d865028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f3c5cc15fa0 RCX: 00007f3c5c99c819
RDX: 0000000020000000 RSI: 0000200000000140 RDI: 0000000000000004
RBP: 00007f3c5ca32c91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f3c5cc16038 R14: 00007f3c5cc15fa0 R15: 00007ffc51a53198
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8e75e5e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
#0: ffffffff8e75e5e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
#0: ffffffff8e75e5e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
2 locks held by getty/5580:
#0: ffff888032f460a0 (&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+0x45c/0x13c0 drivers/tty/n_tty.c:2211
2 locks held by syz.1.10953/13753:
#0: ffffffff8fc3de70 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
#1: ffffffff8ea86b88 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0x141/0x1670 fs/nfsd/nfsctl.c:1903
2 locks held by syz.5.12142/18320:
#0: ffffffff8fc3de70 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
#1: ffffffff8ea86b88 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_version_get_doit+0x17c/0xc40 fs/nfsd/nfsctl.c:1828
2 locks held by syz.4.13670/23856:
#0: ffffffff8fc3de70 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
#1: ffffffff8ea86b88 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_get_doit+0x10a/0x5e0 fs/nfsd/nfsctl.c:2053
1 lock held by syz.0.13705/23981:
#0: ffff8880b01dccc8 (&sb->s_type->i_mutex_key#14){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1028 [inline]
#0: ffff8880b01dccc8 (&sb->s_type->i_mutex_key#14){+.+.}-{4:4}, at: __sock_release net/socket.c:661 [inline]
#0: ffff8880b01dccc8 (&sb->s_type->i_mutex_key#14){+.+.}-{4:4}, at: sock_close+0x9b/0x240 net/socket.c:1455
1 lock held by syz.6.13739/24116:
#0: ffffffff8fbd00c8 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline]
#0: ffffffff8fbd00c8 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x3e/0x1c0 drivers/net/tun.c:3436
2 locks held by syz.6.13739/24130:
#0: ffffffff8fc3de70 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
#1: ffffffff8fbd00c8 (rtnl_mutex){+.+.}-{4:4}, at: nl80211_pre_doit+0x5f/0x930 net/wireless/nl80211.c:18061
1 lock held by syz.6.13739/24131:
#0: ffffffff8fbd00c8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#0: ffffffff8fbd00c8 (rtnl_mutex){+.+.}-{4:4}, at: devinet_ioctl+0x32b/0x1b30 net/ipv4/devinet.c:1120
2 locks held by syz.2.13740/24118:
#0: ffff8880600dfac8 (&sb->s_type->i_mutex_key#14){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1028 [inline]
#0: ffff8880600dfac8 (&sb->s_type->i_mutex_key#14){+.+.}-{4:4}, at: __sock_release net/socket.c:661 [inline]
#0: ffff8880600dfac8 (&sb->s_type->i_mutex_key#14){+.+.}-{4:4}, at: sock_close+0x9b/0x240 net/socket.c:1455
#1: ffffffff8e7648f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline]
#1: ffffffff8e7648f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2d0/0x770 kernel/rcu/tree_exp.h:961
2 locks held by syz.2.13740/24119:
#0: ffffffff8fbc1950 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x4f7/0x730 net/core/net_namespace.c:577
#1: ffffffff8fbd00c8 (rtnl_mutex){+.+.}-{4:4}, at: ip_tunnel_init_net+0x2d7/0x840 net/ipv4/ip_tunnel.c:1146
2 locks held by syz.3.13742/24127:
#0: ffff88805e391ec8 (&sb->s_type->i_mutex_key#14){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1028 [inline]
#0: ffff88805e391ec8 (&sb->s_type->i_mutex_key#14){+.+.}-{4:4}, at: __sock_release net/socket.c:661 [inline]
#0: ffff88805e391ec8 (&sb->s_type->i_mutex_key#14){+.+.}-{4:4}, at: sock_close+0x9b/0x240 net/socket.c:1455
#1: ffff88805b548260 (sk_lock-AF_CAN){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1709 [inline]
#1: ffff88805b548260 (sk_lock-AF_CAN){+.+.}-{0:0}, at: bcm_release+0x1cd/0x940 net/can/bcm.c:1612
2 locks held by syz.3.13742/24128:
#0: ffffffff8fbd00c8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#0: ffffffff8fbd00c8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#0: ffffffff8fbd00c8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_dellink+0x42a/0x820 net/core/rtnetlink.c:3584
#1: ffffffff8e7648f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline]
#1: ffffffff8e7648f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x38d/0x770 kernel/rcu/tree_exp.h:961
2 locks held by syz.3.13742/24129:
#0: ffffffff8f386b08 (ppp_mutex){+.+.}-{4:4}, at: ppp_ioctl+0xdf/0x1b10 drivers/net/ppp/ppp_generic.c:734
#1: ffffffff8fbd00c8 (rtnl_mutex){+.+.}-{4:4}, at: ppp_create_interface drivers/net/ppp/ppp_generic.c:3392 [inline]
#1: ffffffff8fbd00c8 (rtnl_mutex){+.+.}-{4:4}, at: ppp_unattached_ioctl drivers/net/ppp/ppp_generic.c:1065 [inline]
#1: ffffffff8fbd00c8 (rtnl_mutex){+.+.}-{4:4}, at: ppp_ioctl+0x6ce/0x1b10 drivers/net/ppp/ppp_generic.c:738
1 lock held by syz.3.13742/24133:
#0: ffffffff8f386b08 (ppp_mutex){+.+.}-{4:4}, at: ppp_ioctl+0xdf/0x1b10 drivers/net/ppp/ppp_generic.c:734
1 lock held by dhcpcd/24135:
#0: ffff8880adec8260 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1709 [inline]
#0: ffff8880adec8260 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x33/0xe10 net/packet/af_packet.c:3198
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
Call Trace:
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:161 [inline]
__sys_info lib/sys_info.c:157 [inline]
sys_info+0x135/0x170 lib/sys_info.c:165
check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline]
watchdog+0xfd9/0x1030 kernel/hung_task.c:515
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 24131 Comm: syz.6.13739 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
RIP: 0010:kasan_check_range+0x9/0x2c0 mm/kasan/generic.c:199
Code: c6 0c cc 16 8e e8 e7 30 f8 fe 90 0f 0b cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1f 40 d6 55 41 57 41 56 <41> 55 41 54 53 b0 01 48 85 f6 0f 84 ae 01 00 00 4c 8d 04 37 49 39
RSP: 0018:ffffc90006557140 EFLAGS: 00000246
RAX: ffffffff8200f85e RBX: ffffc90006557600 RCX: ffffffff8200f87f
RDX: 0000000000000001 RSI: 0000000000000008 RDI: ffffea0001b1c3c0
RBP: ffffc900065572b0 R08: ffffea0001b1c3c7 R09: 1ffffd4000363878
R10: dffffc0000000000 R11: fffff94000363879 R12: ffffea0001b1c3c0
R13: 0000000000000297 R14: ffffea0001b1c3c0 R15: 0000000000000001
FS: 0000000000000000(0000) GS:ffff888125557000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055d4a75084b0 CR3: 000000008035e000 CR4: 00000000003526f0
Call Trace:
instrument_atomic_read_write include/linux/instrumented.h:112 [inline]
test_and_set_bit_lock include/asm-generic/bitops/instrumented-lock.h:57 [inline]
folio_trylock include/linux/pagemap.h:1122 [inline]
find_lock_entries+0x6cf/0xa90 mm/filemap.c:2184
shmem_undo_range+0x2d6/0x1660 mm/shmem.c:1131
shmem_truncate_range mm/shmem.c:1277 [inline]
shmem_evict_inode+0x240/0x9e0 mm/shmem.c:1407
evict+0x61e/0xb10 fs/inode.c:846
__dentry_kill+0x1a2/0x5e0 fs/dcache.c:670
finish_dput+0xc9/0x480 fs/dcache.c:879
__fput+0x691/0xa70 fs/file_table.c:477
task_work_run+0x1d9/0x270 kernel/task_work.c:233
exit_task_work include/linux/task_work.h:40 [inline]
do_exit+0x70f/0x23c0 kernel/exit.c:976
do_group_exit+0x21b/0x2d0 kernel/exit.c:1118
get_signal+0x1284/0x1330 kernel/signal.c:3034
arch_do_signal_or_restart+0xbc/0x830 arch/x86/kernel/signal.c:337
__exit_to_user_mode_loop kernel/entry/common.c:64 [inline]
exit_to_user_mode_loop+0x86/0x480 kernel/entry/common.c:98
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:325 [inline]
do_syscall_64+0x32d/0xf80 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f9c1119c819
Code: Unable to access opcode bytes at 0x7f9c1119c7ef.
RSP: 002b:00007f9c120b0028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffed RBX: 00007f9c11416180 RCX: 00007f9c1119c819
RDX: 0000200000002280 RSI: 0000000000008914 RDI: 000000000000000e
RBP: 00007f9c11232c91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f9c11416218 R14: 00007f9c11416180 R15: 00007ffe886de508