INFO: task syz-executor0:19251 blocked for more than 140 seconds. Not tainted 4.19.0+ #281 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor0 D17552 19251 5661 0x00000006 Call Trace: context_switch kernel/sched/core.c:2831 [inline] __schedule+0x8cf/0x21d0 kernel/sched/core.c:3472 schedule+0xfe/0x460 kernel/sched/core.c:3516 exp_funnel_lock kernel/rcu/tree_exp.h:319 [inline] _synchronize_rcu_expedited.constprop.58+0x8df/0x9d0 kernel/rcu/tree_exp.h:620 synchronize_rcu_expedited+0x27/0xa0 kernel/rcu/tree_exp.h:758 synchronize_net+0x3b/0x60 net/core/dev.c:9062 packet_set_ring+0x286/0x1da0 net/packet/af_packet.c:4339 packet_release+0x656/0xda0 net/packet/af_packet.c:2998 __sock_release+0xd7/0x250 net/socket.c:579 sock_close+0x19/0x20 net/socket.c:1141 __fput+0x385/0xa30 fs/file_table.c:278 ____fput+0x15/0x20 fs/file_table.c:309 task_work_run+0x1e8/0x2a0 kernel/task_work.c:113 get_signal+0x1558/0x1980 kernel/signal.c:2347 do_signal+0x9c/0x21c0 arch/x86/kernel/signal.c:816 exit_to_usermode_loop+0x2e5/0x380 arch/x86/entry/common.c:162 prepare_exit_to_usermode arch/x86/entry/common.c:197 [inline] syscall_return_slowpath arch/x86/entry/common.c:268 [inline] do_syscall_64+0x6be/0x820 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x457569 Code: 83 c4 18 c3 e8 d8 64 00 00 48 8b 04 24 48 8b 4c 24 08 48 89 01 e8 d7 2d fc ff e8 22 7a fc ff b8 02 00 00 00 48 8d 0d 6a e1 0a <01> 87 01 8b 05 62 e1 0a 01 83 f8 01 0f 85 8a 00 00 00 b8 01 00 00 RSP: 002b:00007f8346d61c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000036 RAX: 0000000000000000 RBX: 0000000000000005 RCX: 0000000000457569 RDX: 0000000000000005 RSI: 0000000000000107 RDI: 0000000000000006 RBP: 000000000072bfa0 R08: 00000000000000c5 R09: 0000000000000000 R10: 0000000020001000 R11: 0000000000000246 R12: 00007f8346d626d4 R13: 00000000004c3c66 R14: 00000000004d5ef0 R15: 00000000ffffffff Showing all locks held in the system: 1 lock held by khungtaskd/1009: #0: 0000000094c99a51 (rcu_read_lock){....}, at: debug_show_all_locks+0xd0/0x424 kernel/locking/lockdep.c:4379 1 lock held by rsyslogd/5532: #0: 0000000008a16f87 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x1bb/0x200 fs/file.c:766 2 locks held by getty/5621: #0: 00000000e459873d (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 000000000ce71a09 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 2 locks held by getty/5622: #0: 0000000015d32bc0 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 000000002a4140b9 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 2 locks held by getty/5623: #0: 000000003f2f51e6 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 00000000ecdc8dbe (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 2 locks held by getty/5624: #0: 00000000a96132aa (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 00000000d5e4bc91 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 2 locks held by getty/5625: #0: 00000000ae5b8472 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 00000000fd3fa4c3 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 2 locks held by getty/5626: #0: 00000000651c89b4 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 0000000094f4d9bf (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 2 locks held by getty/5627: #0: 00000000d7867610 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 000000009943ac49 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 2 locks held by syz-executor0/19251: #0: 0000000024781214 (&sb->s_type->i_mutex_key#11){+.+.}, at: inode_lock include/linux/fs.h:757 [inline] #0: 0000000024781214 (&sb->s_type->i_mutex_key#11){+.+.}, at: __sock_release+0x8b/0x250 net/socket.c:578 #1: 00000000e2824c27 (sk_lock-AF_PACKET){+.+.}, at: lock_sock include/net/sock.h:1492 [inline] #1: 00000000e2824c27 (sk_lock-AF_PACKET){+.+.}, at: packet_release+0x5ff/0xda0 net/packet/af_packet.c:2995 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1009 Comm: khungtaskd Not tainted 4.19.0+ #281 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+0x244/0x39d lib/dump_stack.c:113 nmi_cpu_backtrace.cold.2+0x5c/0xa1 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1e8/0x22a lib/nmi_backtrace.c:62 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38 trigger_all_cpu_backtrace include/linux/nmi.h:144 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:205 [inline] watchdog+0xb51/0x1060 kernel/hung_task.c:289 kthread+0x35a/0x440 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:350 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 skipped: idling at native_safe_halt+0x6/0x10 arch/x86/include/asm/irqflags.h:57