kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] SMP KASAN
CPU: 0 PID: 500 Comm: kworker/u4:4 Not tainted 4.18.0-next-20180814+ #39
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: events_unbound flush_to_ldisc
RIP: 0010:__read_once_size include/linux/compiler.h:188 [inline]
RIP: 0010:sigio_perm fs/fcntl.c:715 [inline]
RIP: 0010:send_sigio_to_task+0x1ad/0x910 fs/fcntl.c:734
Code: 4c 8d b3 00 ff ff ff 48 b8 00 00 00 00 00 fc ff df 49 8d bf 58 06 00 00 4c 89 f2 48 c1 ea 03 c6 04 02 00 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 1a 07 00 00 49 8b 87 58 06 00 00 4c 89 f2 48 c1
RSP: 0018:ffff8801d8fdef48 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: ffff8801d8fdf0c8 RCX: ffffffff81caeb13
RDX: 00000000000000cb RSI: ffffffff81cae4e3 RDI: 0000000000000658
RBP: ffff8801d8fdf0f0 R08: ffff8801d8fce580 R09: ffffed003b6046d6
R10: ffffed003b6046d6 R11: ffff8801db0236b3 R12: ffff8801c33af908
R13: 0000000000000000 R14: ffff8801d8fdefc8 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8801db000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000607304 CR3: 00000001d365f000 CR4: 00000000001406f0
DR0: 000000000000b8c4 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 send_sigio+0x36f/0x4a0 fs/fcntl.c:794
 kill_fasync_rcu fs/fcntl.c:1005 [inline]
 kill_fasync+0x32e/0x640 fs/fcntl.c:1019
 __receive_buf drivers/tty/n_tty.c:1645 [inline]
 n_tty_receive_buf_common+0xfb2/0x2c70 drivers/tty/n_tty.c:1727
 n_tty_receive_buf2+0x33/0x40 drivers/tty/n_tty.c:1762
 tty_ldisc_receive_buf+0xb0/0x190 drivers/tty/tty_buffer.c:456
 tty_port_default_receive_buf+0x115/0x180 drivers/tty/tty_port.c:38
 receive_buf drivers/tty/tty_buffer.c:475 [inline]
 flush_to_ldisc+0x3fd/0x570 drivers/tty/tty_buffer.c:524
 process_one_work+0xc73/0x1aa0 kernel/workqueue.c:2153
 worker_thread+0x189/0x13c0 kernel/workqueue.c:2296
 kthread+0x35a/0x420 kernel/kthread.c:246
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:415
Modules linked in:
Dumping ftrace buffer:
   (ftrace buffer empty)
---[ end trace a4071216684a7b68 ]---
RIP: 0010:__read_once_size include/linux/compiler.h:188 [inline]
RIP: 0010:sigio_perm fs/fcntl.c:715 [inline]
RIP: 0010:send_sigio_to_task+0x1ad/0x910 fs/fcntl.c:734
Code: 4c 8d b3 00 ff ff ff 48 b8 00 00 00 00 00 fc ff df 49 8d bf 58 06 00 00 4c 89 f2 48 c1 ea 03 c6 04 02 00 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 1a 07 00 00 49 8b 87 58 06 00 00 4c 89 f2 48 c1
RSP: 0018:ffff8801d8fdef48 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: ffff8801d8fdf0c8 RCX: ffffffff81caeb13
RDX: 00000000000000cb RSI: ffffffff81cae4e3 RDI: 0000000000000658
RBP: ffff8801d8fdf0f0 R08: ffff8801d8fce580 R09: ffffed003b6046d6
R10: ffffed003b6046d6 R11: ffff8801db0236b3 R12: ffff8801c33af908
R13: 0000000000000000 R14: ffff8801d8fdefc8 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8801db000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000607304 CR3: 00000001d365f000 CR4: 00000000001406f0
DR0: 000000000000b8c4 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400