------------[ cut here ]------------
refcount_t: increment on 0; use-after-free.
WARNING: CPU: 0 PID: 12092 at lib/refcount.c:156 refcount_inc_checked lib/refcount.c:156 [inline]
WARNING: CPU: 0 PID: 12092 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: 12092 Comm: syz-executor.5 Not tainted 5.2.0-rc1+ #7
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/0x744 kernel/panic.c:219
 __warn.cold+0x20/0x4d kernel/panic.c:576
 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:986
RIP: 0010:refcount_inc_checked lib/refcount.c:156 [inline]
RIP: 0010:refcount_inc_checked+0x61/0x70 lib/refcount.c:154
Code: 1d 00 84 48 06 31 ff 89 de e8 1b 6d 3c fe 84 db 75 dd e8 d2 6b 3c fe 48 c7 c7 40 96 a4 87 c6 05 e0 83 48 06 01 e8 3d b1 0e 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:ffff8880635b78a8 EFLAGS: 00010286
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 00000000000129a1 RSI: ffffffff815ac7e6 RDI: ffffed100c6b6f07
RBP: ffff8880635b78b8 R08: ffff88806a72c080 R09: ffffed1015d040f1
R10: ffffed1015d040f0 R11: ffff8880ae820787 R12: ffff888066cc4b30
R13: 0000000000000000 R14: ffff88808f41b7c0 R15: ffff888086557ed0
 kref_get include/linux/kref.h:47 [inline]
 kobject_get+0x66/0xc0 lib/kobject.c:642
 cdev_get+0x60/0xb0 fs/char_dev.c:354
 chrdev_open+0xb0/0x6b0 fs/char_dev.c:399
 do_dentry_open+0x4df/0x1250 fs/open.c:778
 vfs_open+0xa0/0xd0 fs/open.c:887
 do_last fs/namei.c:3416 [inline]
 path_openat+0x10e9/0x46d0 fs/namei.c:3533
 do_filp_open+0x1a1/0x280 fs/namei.c:3563
 do_sys_open+0x3fe/0x5d0 fs/open.c:1070
 __do_compat_sys_open fs/open.c:1107 [inline]
 __se_compat_sys_open fs/open.c:1105 [inline]
 __ia32_compat_sys_open+0x79/0xb0 fs/open.c:1105
 do_syscall_32_irqs_on arch/x86/entry/common.c:337 [inline]
 do_fast_syscall_32+0x27b/0xd7d arch/x86/entry/common.c:408
 entry_SYSENTER_compat+0x70/0x7f arch/x86/entry/entry_64_compat.S:139
RIP: 0023:0xf7fa5849
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:00000000f5d7fc14 EFLAGS: 00000296 ORIG_RAX: 0000000000000005
RAX: ffffffffffffffda RBX: 00000000f5d7fccc RCX: 0000000000000000
RDX: 0000000000000000 RSI: 00000000f5d7fccc RDI: 0000000000000000
RBP: 00000000f5d80168 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
Kernel Offset: disabled
Rebooting in 86400 seconds..