INFO: task syz.5.1245:10038 blocked for more than 143 seconds.
Tainted: G L syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.5.1245 state:D stack:25592 pid:10038 tgid:10038 ppid:6387 task_flags:0x400040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5388 [inline]
__schedule+0x1821/0x5740 kernel/sched/core.c:7189
__schedule_loop kernel/sched/core.c:7268 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7283
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7340
__mutex_lock_common kernel/locking/mutex.c:726 [inline]
__mutex_lock+0x7f7/0x1550 kernel/locking/mutex.c:820
pipe_release+0x48/0x330 fs/pipe.c:729
__fput+0x44f/0xa60 fs/file_table.c:510
task_work_run+0x1d9/0x270 kernel/task_work.c:233
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
__exit_to_user_mode_loop kernel/entry/common.c:67 [inline]
exit_to_user_mode_loop+0xf3/0x4d0 kernel/entry/common.c:98
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:238 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline]
do_syscall_64+0x33e/0xf80 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f39a679ce59
RSP: 002b:00007f39a6b3fba8 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 00007f39a6a17da0 RCX: 00007f39a679ce59
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007f39a6a17da0 R08: 0000000000000006 R09: 0000000000000000
R10: 00007f39a6a17cb0 R11: 0000000000000246 R12: 000000000005cbb1
R13: 00007f39a6a1609c R14: 000000000005caa7 R15: 00007f39a6b3fcb0
INFO: task syz.5.1245:10041 blocked for more than 144 seconds.
Tainted: G L syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.5.1245 state:D stack:26536 pid:10041 tgid:10038 ppid:6387 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5388 [inline]
__schedule+0x1821/0x5740 kernel/sched/core.c:7189
__schedule_loop kernel/sched/core.c:7268 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7283
__lock_sock+0x162/0x2c0 net/core/sock.c:3191
lock_sock_nested+0xc7/0x100 net/core/sock.c:3804
lock_sock include/net/sock.h:1713 [inline]
tcp_splice_read+0x15d/0x940 net/ipv4/tcp.c:838
do_splice_read fs/splice.c:980 [inline]
splice_file_to_pipe+0x446/0x6b0 fs/splice.c:1290
do_splice+0x116f/0x1910 fs/splice.c:1374
__do_splice fs/splice.c:1431 [inline]
__do_sys_splice fs/splice.c:1634 [inline]
__se_sys_splice+0x353/0x490 fs/splice.c:1616
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f39a679ce59
RSP: 002b:00007f39a49f6028 EFLAGS: 00000246 ORIG_RAX: 0000000000000113
RAX: ffffffffffffffda RBX: 00007f39a6a16090 RCX: 00007f39a679ce59
RDX: 0000000000000008 RSI: 0000000000000000 RDI: 0000000000000006
RBP: 00007f39a6832d6f R08: 000000007ffff000 R09: 0000000000000003
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f39a6a16128 R14: 00007f39a6a16090 R15: 00007f39a6b3fa48
Showing all locks held in the system:
1 lock held by khungtaskd/30:
#0: ffffffff8e95cda0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#0: ffffffff8e95cda0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
#0: ffffffff8e95cda0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
7 locks held by kworker/u8:5/137:
1 lock held by udevd/4996:
#0: ffff88801be8d180 (&root->kernfs_rwsem){++++}-{4:4}, at: kernfs_dop_revalidate+0x9e/0x650 fs/kernfs/dir.c:1218
2 locks held by getty/5385:
#0: ffff8880365a00a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000322b2e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13a0 drivers/tty/n_tty.c:2211
1 lock held by syz.5.1245/10038:
#0: ffff88807c722c60 (&pipe->mutex){+.+.}-{4:4}, at: pipe_release+0x48/0x330 fs/pipe.c:729
4 locks held by syz.5.1245/10039:
2 locks held by syz.5.1245/10041:
#0: ffff88807c722c60 (&pipe->mutex){+.+.}-{4:4}, at: splice_file_to_pipe+0x40/0x6b0 fs/splice.c:1287
#1: ffff888077529c60 (sk_lock-AF_INET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1713 [inline]
#1: ffff888077529c60 (sk_lock-AF_INET){+.+.}-{0:0}, at: tcp_splice_read+0x15d/0x940 net/ipv4/tcp.c:838
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
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:162 [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:353 [inline]
watchdog+0xfd3/0x1030 kernel/hung_task.c:561
kthread+0x389/0x470 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 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: 10039 Comm: syz.5.1245 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:lock_acquire+0x34/0x350 kernel/locking/lockdep.c:5828
Code: 55 41 54 53 48 83 ec 60 4d 89 ce 45 89 c7 41 89 cc 89 54 24 04 89 f3 49 89 fd 48 8b ac 24 98 00 00 00 65 48 8b 05 bc aa 97 11 <48> 89 44 24 58 0f 1f 44 00 00 65 8b 05 bf aa 97 11 83 f8 08 0f 83
RSP: 0018:ffffc90000a07fb8 EFLAGS: 00000286
RAX: 64fb0382ebd25c00 RBX: 0000000000000000 RCX: 0000000000000002
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8e95cda0
RBP: ffffffff8176f256 R08: 0000000000000000 R09: 0000000000000000
R10: ffffc90000a08178 R11: ffffffff81b0efc0 R12: 0000000000000002
R13: ffffffff8e95cda0 R14: 0000000000000000 R15: 0000000000000000
FS: 00007f39a75766c0(0000) GS:ffff88812538a000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f9149be8158 CR3: 000000002a29e000 CR4: 00000000003526f0
Call Trace:
rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
rcu_read_lock include/linux/rcupdate.h:838 [inline]
class_rcu_constructor include/linux/rcupdate.h:1181 [inline]
unwind_next_frame+0xc3/0x2550 arch/x86/kernel/unwind_orc.c:495
arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:57 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:584
poison_slab_object mm/kasan/common.c:253 [inline]
__kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285
kasan_slab_free include/linux/kasan.h:235 [inline]
slab_free_hook mm/slub.c:2689 [inline]
slab_free mm/slub.c:6250 [inline]
kmem_cache_free+0x182/0x650 mm/slub.c:6377
inet_frag_reasm_prepare+0x3a2/0xe60 net/ipv4/inet_fragment.c:542
ip_frag_reasm+0xf9/0x7e0 net/ipv4/ip_fragment.c:419
ip_frag_queue net/ipv4/ip_fragment.c:367 [inline]
ip_defrag+0x16c7/0x1f90 net/ipv4/ip_fragment.c:491
ip_local_deliver+0xfb/0x1b0 net/ipv4/ip_input.c:258
NF_HOOK+0x336/0x3c0 include/linux/netfilter.h:318
deliver_ptype_list_skb net/core/dev.c:2507 [inline]
__netif_receive_skb_core+0x2904/0x3170 net/core/dev.c:6155
__netif_receive_skb_one_core net/core/dev.c:6200 [inline]
__netif_receive_skb net/core/dev.c:6315 [inline]
process_backlog+0x76d/0x1950 net/core/dev.c:6666
__napi_poll+0xae/0x340 net/core/dev.c:7733
napi_poll net/core/dev.c:7796 [inline]
net_rx_action+0x627/0xf70 net/core/dev.c:7953
handle_softirqs+0x22a/0x840 kernel/softirq.c:622
do_softirq+0x76/0xd0 kernel/softirq.c:523
__local_bh_enable_ip+0xf8/0x130 kernel/softirq.c:450
local_bh_enable include/linux/bottom_half.h:33 [inline]
rcu_read_unlock_bh include/linux/rcupdate.h:912 [inline]
__dev_queue_xmit+0x1fe5/0x3950 net/core/dev.c:4905
dev_queue_xmit include/linux/netdevice.h:3418 [inline]
neigh_hh_output include/net/neighbour.h:540 [inline]
neigh_output include/net/neighbour.h:554 [inline]
ip_finish_output2+0xc68/0x1070 net/ipv4/ip_output.c:237
ip_do_fragment+0x87c/0x1770 net/ipv4/ip_output.c:915
ip_finish_output_gso net/ipv4/ip_output.c:288 [inline]
__ip_finish_output net/ipv4/ip_output.c:310 [inline]
ip_finish_output+0x3b7/0x530 net/ipv4/ip_output.c:325
NF_HOOK_COND include/linux/netfilter.h:307 [inline]
ip_output+0x29f/0x450 net/ipv4/ip_output.c:438
__ip_queue_xmit+0x116a/0x1bb0 net/ipv4/ip_output.c:534
__tcp_transmit_skb+0x2d76/0x4790 net/ipv4/tcp_output.c:1715
tcp_transmit_skb net/ipv4/tcp_output.c:1733 [inline]
tcp_write_xmit+0x1be0/0x6540 net/ipv4/tcp_output.c:3060
__tcp_push_pending_frames+0x97/0x380 net/ipv4/tcp_output.c:3243
tcp_push_pending_frames include/net/tcp.h:2359 [inline]
tcp_data_snd_check net/ipv4/tcp_input.c:6075 [inline]
tcp_rcv_established+0x1019/0x2800 net/ipv4/tcp_input.c:6658
tcp_v4_do_rcv+0x903/0x13c0 net/ipv4/tcp_ipv4.c:1851
sk_backlog_rcv include/net/sock.h:1190 [inline]
__release_sock+0x265/0x3a0 net/core/sock.c:3216
__sk_flush_backlog+0x36/0xc0 net/core/sock.c:3239
sk_flush_backlog include/net/sock.h:1253 [inline]
tcp_sendmsg_locked+0x4161/0x5360 net/ipv4/tcp.c:1256
tcp_sendmsg+0x2f/0x50 net/ipv4/tcp.c:1455
sock_sendmsg_nosec net/socket.c:787 [inline]
__sock_sendmsg net/socket.c:802 [inline]
__sys_sendto+0x5de/0x710 net/socket.c:2265
__do_sys_sendto net/socket.c:2272 [inline]
__se_sys_sendto net/socket.c:2268 [inline]
__x64_sys_sendto+0xde/0x100 net/socket.c:2268
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f39a679ce59
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f39a7576028 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f39a6a15fa0 RCX: 00007f39a679ce59
RDX: ffffffffffffff75 RSI: 0000200000000040 RDI: 0000000000000006
RBP: 00007f39a6832d6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000020004010 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f39a6a16038 R14: 00007f39a6a15fa0 R15: 00007f39a6b3fa48