syzbot

INFO: task syz-executor.2:24747 blocked for more than 143 seconds.
      Not tainted 5.13.0-rc5-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.2  state:D stack:25392 pid:24747 ppid: 20990 flags:0x00004002
Call Trace:
 context_switch kernel/sched/core.c:4339 [inline]
 __schedule+0xb98/0x1120 kernel/sched/core.c:5147
 schedule+0x14b/0x200 kernel/sched/core.c:5226
 rwsem_down_write_slowpath+0xe52/0x1590 kernel/locking/rwsem.c:1106
 __down_write_common kernel/locking/rwsem.c:1261 [inline]
 __down_write kernel/locking/rwsem.c:1270 [inline]
 down_write+0x165/0x170 kernel/locking/rwsem.c:1407
 unregister_netdevice_notifier+0x8e/0x430 net/core/dev.c:1949
 bcm_release+0x77/0x820 net/can/bcm.c:1474
 __sock_release net/socket.c:599 [inline]
 sock_close+0xd8/0x260 net/socket.c:1258
 __fput+0x352/0x7b0 fs/file_table.c:280
 task_work_run+0x146/0x1c0 kernel/task_work.c:164
 exit_task_work include/linux/task_work.h:32 [inline]
 do_exit+0x736/0x23d0 kernel/exit.c:826
 do_group_exit+0x168/0x2d0 kernel/exit.c:923
 get_signal+0x1770/0x2180 kernel/signal.c:2835
 arch_do_signal_or_restart+0x8e/0x6c0 arch/x86/kernel/signal.c:789
 handle_signal_work kernel/entry/common.c:147 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:171 [inline]
 exit_to_user_mode_prepare+0xac/0x200 kernel/entry/common.c:208
 __syscall_exit_to_user_mode_work kernel/entry/common.c:290 [inline]
 syscall_exit_to_user_mode+0x26/0x70 kernel/entry/common.c:301
 do_syscall_64+0x4b/0xb0 arch/x86/entry/common.c:57
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x4665d9
RSP: 002b:00007fc5d7ef2188 EFLAGS: 00000246 ORIG_RAX: 0000000000000029
RAX: 0000000000000004 RBX: 000000000056c038 RCX: 00000000004665d9
RDX: 0000000000000002 RSI: 0000000000000002 RDI: 000000000000001d
RBP: 00000000004bfcb9 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056c038
R13: 00007ffcedfbd1ff R14: 00007fc5d7ef2300 R15: 0000000000022000

Showing all locks held in the system:
3 locks held by kworker/u4:0/9:
 #0: ffff888012c53138 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x7aa/0x10c0 kernel/workqueue.c:2249
 #1: ffffc90000ce7d20 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x7e8/0x10c0 kernel/workqueue.c:2251
 #2: ffffffff8df1fb30 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0xf0/0xc60 net/core/net_namespace.c:557
1 lock held by khungtaskd/1633:
 #0: ffffffff8cf15cc0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 arch/x86/pci/mmconfig_64.c:151
1 lock held by in:imklog/8078:
 #0: ffff88801da5ed70 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x24e/0x2f0 fs/file.c:974
2 locks held by agetty/8117:
 #0: ffff888020a4c098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:267
 #1: ffffc900010e82e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6c3/0x1cf0 drivers/tty/n_tty.c:2179
2 locks held by kworker/u4:10/21449:
2 locks held by syz-executor.2/24747:
 #0: ffff88807c7fa190 (&sb->s_type->i_mutex_key#13){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:774 [inline]
 #0: ffff88807c7fa190 (&sb->s_type->i_mutex_key#13){+.+.}-{3:3}, at: __sock_release net/socket.c:598 [inline]
 #0: ffff88807c7fa190 (&sb->s_type->i_mutex_key#13){+.+.}-{3:3}, at: sock_close+0x94/0x260 net/socket.c:1258
 #1: ffffffff8df1fb30 (pernet_ops_rwsem){++++}-{3:3}, at: unregister_netdevice_notifier+0x8e/0x430 net/core/dev.c:1949
1 lock held by syz-executor.5/24872:
 #0: ffffffff8df1fb30 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x378/0x5e0 net/core/net_namespace.c:470

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

NMI backtrace for cpu 0
CPU: 0 PID: 1633 Comm: khungtaskd Not tainted 5.13.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:79 [inline]
 dump_stack+0x202/0x31e lib/dump_stack.c:120
 nmi_cpu_backtrace+0x16c/0x190 lib/nmi_backtrace.c:105
 nmi_trigger_cpumask_backtrace+0x191/0x2f0 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:209 [inline]
 watchdog+0xcfb/0xd40 kernel/hung_task.c:294
 kthread+0x39a/0x3c0 kernel/kthread.c:313
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 4847 Comm: systemd-journal Not tainted 5.13.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:check_kcov_mode kernel/kcov.c:174 [inline]
RIP: 0010:write_comp_data kernel/kcov.c:218 [inline]
RIP: 0010:__sanitizer_cov_trace_const_cmp4+0x31/0xa0 kernel/kcov.c:284
Code: 14 25 80 ef 01 00 65 8b 05 54 d0 82 7e a9 00 01 ff 00 74 10 a9 00 01 00 00 74 6e 83 ba 3c 15 00 00 00 74 65 8b 82 18 15 00 00 <83> f8 03 75 5a 48 8b 8a 20 15 00 00 44 8b 8a 1c 15 00 00 49 c1 e1
RSP: 0018:ffffc90000edfde8 EFLAGS: 00000246
RAX: 0000000000000000 RBX: ffff888036fc5510 RCX: ffff8880137c0000
RDX: ffff8880137c0000 RSI: 0000000000000031 RDI: 0000000000000000
RBP: 0000000000000031 R08: ffffffff81d4a4dd R09: fffff940001b7e01
R10: fffff940001b7e01 R11: 0000000000000000 R12: 1ffff11006df8aa2
R13: ffff8880137c0888 R14: ffff888036fc5500 R15: 1ffff110026f8111
FS:  00007f0f3f66f8c0(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000c00beb22c8 CR3: 00000000177e3000 CR4: 00000000001506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 getname_flags+0x15d/0x640 fs/namei.c:191
 getname fs/namei.c:209 [inline]
 user_path_create fs/namei.c:3650 [inline]
 do_mkdirat+0x91/0x3e0 fs/namei.c:3828
 do_syscall_64+0x3f/0xb0 arch/x86/entry/common.c:47
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f0f3e92a687
Code: 00 b8 ff ff ff ff c3 0f 1f 40 00 48 8b 05 09 d8 2b 00 64 c7 00 5f 00 00 00 b8 ff ff ff ff c3 0f 1f 40 00 b8 53 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d e1 d7 2b 00 f7 d8 64 89 01 48
RSP: 002b:00007ffc85e63ad8 EFLAGS: 00000293 ORIG_RAX: 0000000000000053
RAX: ffffffffffffffda RBX: 00007ffc85e669f0 RCX: 00007f0f3e92a687
RDX: 00007f0f3f39ba00 RSI: 00000000000001ed RDI: 000055f6dd3678a0
RBP: 00007ffc85e63b10 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000069 R11: 0000000000000293 R12: 0000000000000000
R13: 0000000000000000 R14: 00007ffc85e669f0 R15: 00007ffc85e64000