[syzbot] BUG: corrupted list in hci_conn_add_sysfs

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 16c9f284e746 Merge branch 'for-next/core', remote-tracking..
git tree: git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci
console output: https://syzkaller.appspot.com/x/log.txt?x=13a8f554880000
kernel config: https://syzkaller.appspot.com/x/.config?x=15a770deac0c935a
dashboard link: https://syzkaller.appspot.com/bug?extid=b30ccad4684cce846cef
compiler: Debian clang version 13.0.1-++20220126092033+75e33f71c2da-1~exp1~20220126212112.63, GNU ld (GNU Binutils for Debian) 2.35.2
userspace arch: arm64
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1221ebac880000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=109c44df080000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/fd8978a3a764/disk-16c9f284.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/73ab1c321ad6/vmlinux-16c9f284.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+b30cca...@syzkaller.appspotmail.com

Bluetooth: hci0: failed to register connection device
list_add corruption. prev->next should be next (ffff0000c94de240), but was 623d4d4554535953. (prev=ffff0000c957fe68).
------------[ cut here ]------------
kernel BUG at lib/list_debug.c:32!
Internal error: Oops - BUG: 00000000f2000800 [#1] PREEMPT SMP
Modules linked in:
CPU: 0 PID: 3060 Comm: kworker/u5:1 Not tainted 6.0.0-rc6-syzkaller-17739-g16c9f284e746 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/26/2022
Workqueue: hci0 hci_rx_work
pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : __list_add_valid+0xb4/0xb8 lib/list_debug.c:30
lr : __list_add_valid+0xb4/0xb8 lib/list_debug.c:30
sp : ffff8000126f3ad0
x29: ffff8000126f3ad0 x28: ffff0000c9208000 x27: 0000000000000000
x26: 0000000000000000 x25: ffff0000caae5014 x24: 0000000000000000
x23: ffff0000c94de240 x22: ffff0000c957fe68 x21: ffff0000c0c03e68
x20: ffff0000c0c03e60 x19: ffff0000c94de200 x18: 00000000000000c0
x17: 3034326564343963 x16: ffff80000db59158 x15: ffff0000c596b500
x14: 0000000000000000 x13: 00000000ffffffff x12: ffff0000c596b500
x11: ff808000081c30a4 x10: 0000000000000000 x9 : 007b181e3ceb7100
x8 : 007b181e3ceb7100 x7 : ffff8000081976e4 x6 : 0000000000000000
x5 : 0000000000000080 x4 : 0000000000000001 x3 : 0000000000000000
x2 : ffff0001fefbecd0 x1 : 0000000100000001 x0 : 0000000000000075
Call trace:
__list_add_valid+0xb4/0xb8 lib/list_debug.c:30
__list_add include/linux/list.h:69 [inline]
list_add_tail include/linux/list.h:102 [inline]
add_tail lib/klist.c:104 [inline]
klist_add_tail+0x9c/0xd8 lib/klist.c:137
device_add+0x7a8/0x958 drivers/base/core.c:3528
hci_conn_add_sysfs+0x4c/0xf4 net/bluetooth/hci_sysfs.c:53
le_conn_complete_evt+0x858/0xae0 net/bluetooth/hci_event.c:5917
hci_le_conn_complete_evt+0x58/0xa4 net/bluetooth/hci_event.c:5966
hci_le_meta_evt+0x1e4/0x230 net/bluetooth/hci_event.c:7110
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x4e0/0x60c net/bluetooth/hci_event.c:7495
hci_rx_work+0x1a4/0x2f4 net/bluetooth/hci_core.c:4007
process_one_work+0x2d8/0x504 kernel/workqueue.c:2289
worker_thread+0x340/0x610 kernel/workqueue.c:2436
kthread+0x12c/0x158 kernel/kthread.c:376
ret_from_fork+0x10/0x20
Code: 91257400 aa0303e1 aa0803e3 94a78613 (d4210000)
---[ end trace 0000000000000000 ]---


---
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[syzbot]

syzbot suspects this issue was fixed by commit:

commit 448a496f760664d3e2e79466aa1787e6abc922b5
Author: Luiz Augusto von Dentz <luiz.vo...@intel.com>
Date: Mon Sep 19 17:56:59 2022 +0000

Bluetooth: hci_sysfs: Fix attempting to call device_add multiple times

bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=1052f8fe880000
start commit: dc164f4fb00a Merge tag 'for-linus-6.0-rc7' of git://git.ke..
git tree: upstream
kernel config: https://syzkaller.appspot.com/x/.config?x=122d7bd4fc8e0ecb
dashboard link: https://syzkaller.appspot.com/bug?extid=b30ccad4684cce846cef
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1110db8c880000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=13e58aef080000

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

#syz fix: Bluetooth: hci_sysfs: Fix attempting to call device_add multiple times

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

[Dmitry Vyukov]

Looks reasonable based on subsystem and the patch:

[Luiz Augusto von Dentz]

Hi,

Looks like I did add a different link when fixing it:

https://git.kernel.org/pub/scm/linux/kernel/git/bluetooth/bluetooth-next.git/commit/?id=448a496f760664d3e2e79466aa1787e6abc922b5

Or perhaps they are duplicated?

https://syzkaller.appspot.com/bug?id=da3246e2d33afdb92d66bc166a0934c5b146404a
https://syzkaller.appspot.com/bug?extid=b30ccad4684cce846cef

--
Luiz Augusto von Dentz

[Dmitry Vyukov]

Yes, most likely differently looking crashes, but the same root cause.
It happens.