syzbot

INFO: task syz-executor013:8221 blocked for more than 143 seconds.
      Not tainted 5.4.0-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor013 D27496  8221   8219 0x00004000
Call Trace:
 context_switch kernel/sched/core.c:3385 [inline]
 __schedule+0x837/0xc50 kernel/sched/core.c:4081
 schedule+0x181/0x210 kernel/sched/core.c:4155
 __lock_sock+0x164/0x2b0 net/core/sock.c:2413
 lock_sock_nested+0x7c/0x120 net/core/sock.c:2938
 virtio_transport_release+0x5e/0xd40 net/vmw_vsock/virtio_transport_common.c:822
 vsock_assign_transport+0x19e/0x3b0 net/vmw_vsock/af_vsock.c:437
 vsock_stream_connect+0x46d/0xb50 net/vmw_vsock/af_vsock.c:1268
 __sys_connect_file+0x279/0x2f0 net/socket.c:1847
 __sys_connect net/socket.c:1860 [inline]
 __do_sys_connect net/socket.c:1871 [inline]
 __se_sys_connect net/socket.c:1868 [inline]
 __x64_sys_connect+0xa2/0xf0 net/socket.c:1868
 do_syscall_64+0xf7/0x1c0 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x4401b9
Code: Bad RIP value.
RSP: 002b:00007fff1f12a168 EFLAGS: 00000246 ORIG_RAX: 000000000000002a
RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 00000000004401b9
RDX: 0000000000000010 RSI: 00000000200000c0 RDI: 0000000000000003
RBP: 00000000006ca018 R08: 00000000004002c8 R09: 00000000004002c8
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000401a40
R13: 0000000000401ad0 R14: 0000000000000000 R15: 0000000000000000

Showing all locks held in the system:
1 lock held by khungtaskd/1099:
 #0: ffffffff890d4bc0 (rcu_read_lock){....}, at: rcu_lock_acquire+0x4/0x30 include/linux/rcupdate.h:207
2 locks held by rsyslogd/8108:
 #0: ffff88809bbf6120 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x243/0x2e0 fs/file.c:801
 #1: ffff8880aeb36f98 (&rq->lock){-.-.}, at: __fs_reclaim_acquire+0x4/0x30 mm/page_alloc.c:4083
2 locks held by getty/8198:
 #0: ffff888095e65090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:272
 #1: ffffc90005f3d2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x221/0x1b00 drivers/tty/n_tty.c:2156
2 locks held by getty/8199:
 #0: ffff8880a7aaa090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:272
 #1: ffffc90005f552e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x221/0x1b00 drivers/tty/n_tty.c:2156
2 locks held by getty/8200:
 #0: ffff8880946a5090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:272
 #1: ffffc90005f412e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x221/0x1b00 drivers/tty/n_tty.c:2156
2 locks held by getty/8201:
 #0: ffff8880964bb090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:272
 #1: ffffc90005f452e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x221/0x1b00 drivers/tty/n_tty.c:2156
2 locks held by getty/8202:
 #0: ffff8880912b0090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:272
 #1: ffffc90005f512e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x221/0x1b00 drivers/tty/n_tty.c:2156
2 locks held by getty/8203:
 #0: ffff8880963fc090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:272
 #1: ffffc90005f312e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x221/0x1b00 drivers/tty/n_tty.c:2156
2 locks held by getty/8204:
 #0: ffff8880a0b58090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:272
 #1: ffffc90005f252e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x221/0x1b00 drivers/tty/n_tty.c:2156
1 lock held by syz-executor013/8221:
 #0: ffff8880a38668d0 (sk_lock-AF_VSOCK){+.+.}, at: lock_sock include/net/sock.h:1526 [inline]
 #0: ffff8880a38668d0 (sk_lock-AF_VSOCK){+.+.}, at: vsock_stream_connect+0x110/0xb50 net/vmw_vsock/af_vsock.c:1238

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

NMI backtrace for cpu 0
CPU: 0 PID: 1099 Comm: khungtaskd Not tainted 5.4.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1fb/0x318 lib/dump_stack.c:118
 nmi_cpu_backtrace+0xaf/0x1a0 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x174/0x290 lib/nmi_backtrace.c:62
 arch_trigger_cpumask_backtrace+0x10/0x20 arch/x86/kernel/apic/hw_nmi.c:38
 trigger_all_cpu_backtrace+0x17/0x20 include/linux/nmi.h:146
 check_hung_uninterruptible_tasks kernel/hung_task.c:205 [inline]
 watchdog+0xd49/0xd60 kernel/hung_task.c:289
 kthread+0x332/0x350 kernel/kthread.c:255
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1 skipped: idling at native_safe_halt+0xe/0x10 arch/x86/include/asm/irqflags.h:60