WARNING: ODEBUG bug in bt_host_release

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: ac3a0c84 Merge git://git.kernel.org/pub/scm/linux/kernel/g..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=11e1da92900000
kernel config: https://syzkaller.appspot.com/x/.config?x=e59ee776d5aa8d55
dashboard link: https://syzkaller.appspot.com/bug?extid=0ce8a29c6c6469b16632
compiler: clang version 10.0.0 (https://github.com/llvm/llvm-project/ c2443155a0fb245c8f17f2c1c72b6ea391e86e81)
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=14f653ca900000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+0ce8a2...@syzkaller.appspotmail.com

------------[ cut here ]------------
ODEBUG: free active (active state 0) object type: timer_list hint: delayed_work_timer_fn+0x0/0x80 arch/x86/include/asm/paravirt.h:770
WARNING: CPU: 1 PID: 20314 at lib/debugobjects.c:488 debug_print_object lib/debugobjects.c:485 [inline]
WARNING: CPU: 1 PID: 20314 at lib/debugobjects.c:488 __debug_check_no_obj_freed lib/debugobjects.c:967 [inline]
WARNING: CPU: 1 PID: 20314 at lib/debugobjects.c:488 debug_check_no_obj_freed+0x45c/0x640 lib/debugobjects.c:998
Kernel panic - not syncing: panic_on_warn set ...
CPU: 1 PID: 20314 Comm: syz-executor.5 Not tainted 5.8.0-rc7-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+0x1f0/0x31e lib/dump_stack.c:118
panic+0x264/0x7a0 kernel/panic.c:231
__warn+0x227/0x250 kernel/panic.c:600
report_bug+0x1b1/0x2e0 lib/bug.c:198
handle_bug+0x42/0x80 arch/x86/kernel/traps.c:235
exc_invalid_op+0x16/0x40 arch/x86/kernel/traps.c:255
asm_exc_invalid_op+0x12/0x20 arch/x86/include/asm/idtentry.h:540
RIP: 0010:debug_print_object lib/debugobjects.c:485 [inline]
RIP: 0010:__debug_check_no_obj_freed lib/debugobjects.c:967 [inline]
RIP: 0010:debug_check_no_obj_freed+0x45c/0x640 lib/debugobjects.c:998
Code: 74 08 4c 89 f7 e8 04 e4 11 fe 4d 8b 06 48 c7 c7 ef b7 14 89 48 c7 c6 fd 95 12 89 48 89 da 89 e9 4d 89 f9 31 c0 e8 64 95 a4 fd <0f> 0b 48 ba 00 00 00 00 00 fc ff df ff 05 86 c1 eb 05 48 8b 5c 24
RSP: 0018:ffffc90003777b90 EFLAGS: 00010046
RAX: ffd2d42dae8b6000 RBX: ffffffff8918b660 RCX: ffff888087ef6000
RDX: 0000000000000000 RSI: 0000000080000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: ffffffff815dd389 R09: ffffed1015d241c3
R10: ffffed1015d241c3 R11: 0000000000000000 R12: ffff8880a131c9ec
R13: ffffffff8ba5dfb8 R14: ffffffff894edb20 R15: ffffffff814c4b60
kfree+0xfc/0x220 mm/slab.c:3756
bt_host_release+0x18/0x20 net/bluetooth/hci_sysfs.c:86
device_release+0x70/0x1a0 drivers/base/core.c:1575
kobject_cleanup lib/kobject.c:693 [inline]
kobject_release lib/kobject.c:722 [inline]
kref_put include/linux/kref.h:65 [inline]
kobject_put+0x15b/0x220 lib/kobject.c:739
vhci_release+0x7b/0xc0 drivers/bluetooth/hci_vhci.c:341
__fput+0x2f0/0x750 fs/file_table.c:281
task_work_run+0x137/0x1c0 kernel/task_work.c:135
exit_task_work include/linux/task_work.h:25 [inline]
do_exit+0x601/0x1f80 kernel/exit.c:805
do_group_exit+0x161/0x2d0 kernel/exit.c:903
__do_sys_exit_group+0x13/0x20 kernel/exit.c:914
__se_sys_exit_group+0x10/0x10 kernel/exit.c:912
__x64_sys_exit_group+0x37/0x40 kernel/exit.c:912
do_syscall_64+0x73/0xe0 arch/x86/entry/common.c:384
entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x45cc79
Code: Bad RIP value.
RSP: 002b:00007ffe023458d8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000045cc79
RDX: 00000000004166d1 RSI: 0000000000ca85f0 RDI: 0000000000000043
RBP: 00000000004c2903 R08: 000000000000000b R09: 0000000000000000
R10: 000000000246f940 R11: 0000000000000246 R12: 0000000000000004
R13: 00007ffe02345a20 R14: 00000000000b206f R15: 00007ffe02345a30
Kernel Offset: disabled
Rebooting in 86400 seconds..


---
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[SyzScope]

Hi,

This is SyzScope, a research project that aims to reveal high-risk
primitives from a seemingly low-risk bug (UAF/OOB read, WARNING, BUG, etc.).

We are currently testing seemingly low-risk bugs on syzbot's open
section(https://syzkaller.appspot.com/upstream), and try to reach out to
kernel developers as long as SyzScope discovers any high-risk primitives.

Regrading the bug "WARNING: ODEBUG bug in bt_host_release", SyzScope
reports 146 memory write primitives, and 7 control flow hijacking
primitives.

The detailed comments can be found at
https://sites.google.com/view/syzscope/warning-odebug-bug-in-bt_host_release

Please let us know if SyzScope indeed helps, and any suggestions/feedback.

[syzbot]

syzbot suspects this issue was fixed by commit:

commit e2cb6b891ad2b8caa9131e3be70f45243df82a80
Author: Lin Ma <li...@zju.edu.cn>
Date: Mon Apr 12 11:17:57 2021 +0000

bluetooth: eliminate the potential race condition when removing the HCI controller

bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=15427145d00000
start commit: f873db9a Merge tag 'io_uring-5.9-2020-08-21' of git://git...
git tree: upstream
kernel config: https://syzkaller.appspot.com/x/.config?x=bb68b9e8a8cc842f
dashboard link: https://syzkaller.appspot.com/bug?extid=0ce8a29c6c6469b16632
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=10310972900000

If the result looks correct, please mark the issue as fixed by replying with:

#syz fix: bluetooth: eliminate the potential race condition when removing the HCI controller

For information about bisection process see: https://goo.gl/tpsmEJ#bisection

[Dmitry Vyukov]

Looks reasonable based on the commit and bisection log.
Unfortunately I cannot easily send this as my email client will wrap
the commit title line (longer than 80 chars)...

[Tetsuo Handa]

Bisection log looks reasonable.