INFO: task syz.5.3717:15687 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.5.3717 state:D stack:23248 pid:15687 ppid: 7750 flags:0x00004006
Call Trace:
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11c3/0x4350 kernel/sched/core.c:6395
schedule+0x11b/0x1e0 kernel/sched/core.c:6478
perf_pending_task_sync+0x13c/0x1c0 kernel/events/core.c:5137
_free_event+0x34/0xe30 kernel/events/core.c:5143
put_event kernel/events/core.c:5268 [inline]
perf_event_release_kernel+0x7c4/0x850 kernel/events/core.c:5393
perf_release+0x37/0x40 kernel/events/core.c:5403
__fput+0x212/0x8c0 fs/file_table.c:311
task_work_run+0x125/0x1a0 kernel/task_work.c:188
get_signal+0x123e/0x12e0 kernel/signal.c:2685
arch_do_signal_or_restart+0xe6/0x12a0 arch/x86/kernel/signal.c:867
handle_signal_work kernel/entry/common.c:157 [inline]
exit_to_user_mode_loop+0x9e/0x130 kernel/entry/common.c:181
exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:217
__syscall_exit_to_user_mode_work kernel/entry/common.c:299 [inline]
syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:310
do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f5ac64c71d9
RSP: 002b:00007f5ac46fdfd8 EFLAGS: 00000206 ORIG_RAX: 0000000000000038
RAX: fffffffffffffffc RBX: 00007f5ac674f090 RCX: 00007f5ac64c71d9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000040004000
RBP: 00007f5ac655e888 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 00007f5ac674f128 R14: 00007f5ac674f090 R15: 00007fff27d97d88
INFO: task syz.1.3755:15814 blocked for more than 144 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.3755 state:D stack:23568 pid:15814 ppid: 13318 flags:0x00004006
Call Trace:
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11c3/0x4350 kernel/sched/core.c:6395
schedule+0x11b/0x1e0 kernel/sched/core.c:6478
perf_pending_task_sync+0x13c/0x1c0 kernel/events/core.c:5137
_free_event+0x34/0xe30 kernel/events/core.c:5143
put_event kernel/events/core.c:5268 [inline]
perf_event_release_kernel+0x7c4/0x850 kernel/events/core.c:5393
perf_release+0x37/0x40 kernel/events/core.c:5403
__fput+0x212/0x8c0 fs/file_table.c:311
task_work_run+0x125/0x1a0 kernel/task_work.c:188
get_signal+0x123e/0x12e0 kernel/signal.c:2685
arch_do_signal_or_restart+0xe6/0x12a0 arch/x86/kernel/signal.c:867
handle_signal_work kernel/entry/common.c:157 [inline]
exit_to_user_mode_loop+0x9e/0x130 kernel/entry/common.c:181
exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:217
__syscall_exit_to_user_mode_work kernel/entry/common.c:299 [inline]
syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:310
do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f1c97f491d9
RSP: 002b:00007f1c961a0fd8 EFLAGS: 00000206 ORIG_RAX: 0000000000000038
RAX: fffffffffffffffc RBX: 00007f1c981d0fa0 RCX: 00007f1c97f491d9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000040004000
RBP: 00007f1c97fe0888 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 00007f1c981d1038 R14: 00007f1c981d0fa0 R15: 00007ffd2166a2c8
Showing all locks held in the system:
1 lock held by khungtaskd/27:
#0: ffffffff8d11efa0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
2 locks held by getty/3940:
#0: ffff88814c6ab098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
#1: ffffc90002cf62e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x594/0x1a50 drivers/tty/n_tty.c:2158
4 locks held by kworker/u4:5/4243:
2 locks held by kworker/u4:6/4244:
3 locks held by kworker/1:9/15475:
#0: ffff888017870938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x75c/0xff0 kernel/workqueue.c:-1
#1: ffffc9000328fd00 (fqdir_free_work){+.+.}-{0:0}, at: process_one_work+0x79e/0xff0 kernel/workqueue.c:2285
#2: ffffffff8d123930 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0xa1/0x4c0 kernel/rcu/tree.c:4043
2 locks held by syz.4.4710/19563:
#0: ffffffff8e241690 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x324/0x5b0 net/core/net_namespace.c:499
#1: ffffffff8d123930 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0xa1/0x4c0 kernel/rcu/tree.c:4043
2 locks held by syz.2.4718/19590:
2 locks held by syz.3.4722/19603:
=============================================
NMI backtrace for cpu 0
CPU: 0 PID: 27 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Call Trace:
dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106
nmi_cpu_backtrace+0x3a2/0x3d0 lib/nmi_backtrace.c:111
nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:212 [inline]
watchdog+0xe1b/0xe60 kernel/hung_task.c:369
kthread+0x42e/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 3539 Comm: syslogd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x60 kernel/kcov.c:201
Code: 2e 0f 1f 84 00 00 00 00 00 90 53 48 89 fb e8 17 00 00 00 48 8b 3d 00 07 f2 0c 48 89 de 5b e9 87 7c 44 00 00 00 cc cc 00 00 cc <48> 8b 04 24 65 48 8b 0d 54 4c 89 7e 65 8b 15 55 4c 89 7e 81 e2 00
RSP: 0018:ffffc90002ddf8e8 EFLAGS: 00000202
RAX: ffffffff81c6fff5 RBX: 000000000000005e RCX: ffff88807ddf0000
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: 000000000090ea40 R08: ffffffff8e6b282f R09: 1ffffffff1cd6505
R10: dffffc0000000000 R11: fffffbfff1cd6506 R12: dffffc0000000000
R13: 0000000000000001 R14: ffff8880243a9000 R15: ffffea000090ea01
FS: 00007f5cd900dc80(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055556f3b54e8 CR3: 000000002bde5000 CR4: 00000000003506e0
DR0: 0000200000000300 DR1: 0000200000000300 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
_compound_head include/linux/page-flags.h:199 [inline]
check_heap_object mm/usercopy.c:236 [inline]
__check_object_size+0x320/0x410 mm/usercopy.c:286
check_object_size include/linux/thread_info.h:199 [inline]
check_copy_size include/linux/thread_info.h:232 [inline]
copy_to_iter include/linux/uio.h:155 [inline]
simple_copy_to_iter+0x3e/0x60 net/core/datagram.c:527
__skb_datagram_iter+0xde/0x740 net/core/datagram.c:425
skb_copy_datagram_iter+0xad/0x1f0 net/core/datagram.c:541
skb_copy_datagram_msg include/linux/skbuff.h:3773 [inline]
__unix_dgram_recvmsg+0x695/0xd50 net/unix/af_unix.c:2354
sock_recvmsg_nosec net/socket.c:969 [inline]
sock_recvmsg net/socket.c:987 [inline]
sock_read_iter+0x2c2/0x380 net/socket.c:1068
call_read_iter include/linux/fs.h:2173 [inline]
new_sync_read fs/read_write.c:404 [inline]
vfs_read+0x75e/0xd50 fs/read_write.c:485
ksys_read+0x153/0x260 fs/read_write.c:623
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f5cd915d407
Code: 48 89 fa 4c 89 df e8 38 aa 00 00 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 1a 5b c3 0f 1f 84 00 00 00 00 00 48 8b 44 24 10 0f 05 <5b> c3 0f 1f 80 00 00 00 00 83 e2 39 83 fa 08 75 de e8 23 ff ff ff
RSP: 002b:00007ffd727a97f0 EFLAGS: 00000202 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 00007f5cd900dc80 RCX: 00007f5cd915d407
RDX: 00000000000000ff RSI: 00005627e197c950 RDI: 0000000000000000
RBP: 00005627e197c910 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 00005627e197c9a0
R13: 0000000000000000 R14: 00005627e197c950 R15: 00005627d0b19d98