------------[ cut here ]------------
refcount_t: increment on 0; use-after-free.
WARNING: CPU: 0 PID: 9667 at lib/refcount.c:156 refcount_inc_checked lib/refcount.c:156 [inline]
WARNING: CPU: 0 PID: 9667 at lib/refcount.c:156 refcount_inc_checked+0x61/0x70 lib/refcount.c:154
Kernel panic - not syncing: panic_on_warn set ...
CPU: 0 PID: 9667 Comm: syz-executor908 Not tainted 5.1.0-rc4+ #67
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+0x172/0x1f0 lib/dump_stack.c:113
 panic+0x2cb/0x65c kernel/panic.c:214
 __warn.cold+0x20/0x45 kernel/panic.c:571
 report_bug+0x263/0x2b0 lib/bug.c:186
 fixup_bug arch/x86/kernel/traps.c:179 [inline]
 fixup_bug arch/x86/kernel/traps.c:174 [inline]
 do_error_trap+0x11b/0x200 arch/x86/kernel/traps.c:272
 do_invalid_op+0x37/0x50 arch/x86/kernel/traps.c:291
 invalid_op+0x14/0x20 arch/x86/entry/entry_64.S:973
RIP: 0010:refcount_inc_checked lib/refcount.c:156 [inline]
RIP: 0010:refcount_inc_checked+0x61/0x70 lib/refcount.c:154
Code: 1d 86 4c 2a 06 31 ff 89 de e8 8b 55 40 fe 84 db 75 dd e8 42 54 40 fe 48 c7 c7 00 72 a1 87 c6 05 66 4c 2a 06 01 e8 2d 02 13 fe <0f> 0b eb c1 90 90 90 90 90 90 90 90 90 90 90 55 48 89 e5 41 57 41
RSP: 0018:ffff8880905c78a8 EFLAGS: 00010286
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff815afcb6 RDI: ffffed10120b8f07
RBP: ffff8880905c78b8 R08: ffff8880864c4240 R09: ffffed1015d05011
R10: ffffed1015d05010 R11: ffff8880ae828087 R12: ffff88808f00cbf8
R13: 0000000000000000 R14: ffff8880989e7cc0 R15: ffff8880a53fb4b8
 kref_get include/linux/kref.h:47 [inline]
 kobject_get+0x66/0xc0 lib/kobject.c:613
 cdev_get+0x60/0xb0 fs/char_dev.c:358
 chrdev_open+0xb0/0x6b0 fs/char_dev.c:403
 do_dentry_open+0x4e2/0x1250 fs/open.c:777
 vfs_open+0xa0/0xd0 fs/open.c:886
 do_last fs/namei.c:3416 [inline]
 path_openat+0x10e9/0x46e0 fs/namei.c:3533
 do_filp_open+0x1a1/0x280 fs/namei.c:3563
 do_sys_open+0x3fe/0x5d0 fs/open.c:1069
 __do_compat_sys_open fs/open.c:1106 [inline]
 __se_compat_sys_open fs/open.c:1104 [inline]
 __ia32_compat_sys_open+0x79/0xb0 fs/open.c:1104
 do_syscall_32_irqs_on arch/x86/entry/common.c:326 [inline]
 do_fast_syscall_32+0x281/0xc98 arch/x86/entry/common.c:397
 entry_SYSENTER_compat+0x70/0x7f arch/x86/entry/entry_64_compat.S:139
RIP: 0023:0xf7fbe869
Code: 85 d2 74 02 89 0a 5b 5d c3 8b 04 24 c3 8b 14 24 c3 8b 3c 24 c3 90 90 90 90 90 90 90 90 90 90 90 90 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 eb 0d 90 90 90 90 90 90 90 90 90 90 90 90
RSP: 002b:00000000f7f98dc4 EFLAGS: 00000296 ORIG_RAX: 0000000000000005
RAX: ffffffffffffffda RBX: 00000000f7f98dfc RCX: 0000000000000000
RDX: 0000000000000000 RSI: 00000000f7f98dfc RDI: 0000000066666667
RBP: 00000000080fb010 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
Kernel Offset: disabled
Rebooting in 86400 seconds..