Linux-Bluetooth Archive on lore.kernel.org
 help / color / Atom feed
From: syzbot <syzbot+2e9900a1e1b3c9c96a77@syzkaller.appspotmail.com>
To: davem@davemloft.net, hdanton@sina.com, johan.hedberg@gmail.com,
	kuba@kernel.org, linux-bluetooth@vger.kernel.org,
	linux-kernel@vger.kernel.org, marcel@holtmann.org,
	netdev@vger.kernel.org, syzkaller-bugs@googlegroups.com
Subject: Re: WARNING: refcount bug in do_enable_set
Date: Sun, 02 Aug 2020 07:58:15 -0700
Message-ID: <00000000000075030605abe640e5@google.com> (raw)
In-Reply-To: <0000000000008b9e0705a38afe52@google.com>

syzbot has found a reproducer for 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=1194935c900000
kernel config:  https://syzkaller.appspot.com/x/.config?x=e59ee776d5aa8d55
dashboard link: https://syzkaller.appspot.com/bug?extid=2e9900a1e1b3c9c96a77
compiler:       clang version 10.0.0 (https://github.com/llvm/llvm-project/ c2443155a0fb245c8f17f2c1c72b6ea391e86e81)
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=10b7ddca900000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=126dcf6c900000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+2e9900a1e1b3c9c96a77@syzkaller.appspotmail.com

------------[ cut here ]------------
refcount_t: underflow; use-after-free.
WARNING: CPU: 1 PID: 2540 at lib/refcount.c:28 refcount_warn_saturate+0x15b/0x1a0 lib/refcount.c:28
Kernel panic - not syncing: panic_on_warn set ...
CPU: 1 PID: 2540 Comm: kworker/1:8 Not tainted 5.8.0-rc7-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: events do_enable_set
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:refcount_warn_saturate+0x15b/0x1a0 lib/refcount.c:28
Code: c7 8a af 14 89 31 c0 e8 b3 f2 a8 fd 0f 0b eb 85 e8 2a 32 d7 fd c6 05 a4 d9 eb 05 01 48 c7 c7 b6 af 14 89 31 c0 e8 95 f2 a8 fd <0f> 0b e9 64 ff ff ff e8 09 32 d7 fd c6 05 84 d9 eb 05 01 48 c7 c7
RSP: 0018:ffffc90007d27c48 EFLAGS: 00010246
RAX: adb9104953f59b00 RBX: 0000000000000003 RCX: ffff8880a02d0540
RDX: 0000000000000000 RSI: 0000000080000000 RDI: 0000000000000000
RBP: 0000000000000003 R08: ffffffff815dd389 R09: ffffed1015d262c0
R10: ffffed1015d262c0 R11: 0000000000000000 R12: dffffc0000000000
R13: ffff8880a0259118 R14: dffffc0000000000 R15: ffff8880ae9350c0
 do_enable_set+0x66e/0x900 net/bluetooth/6lowpan.c:1083
 process_one_work+0x789/0xfc0 kernel/workqueue.c:2269
 worker_thread+0xaa4/0x1460 kernel/workqueue.c:2415
 kthread+0x37e/0x3a0 drivers/block/aoe/aoecmd.c:1234
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:293
Kernel Offset: disabled
Rebooting in 86400 seconds..


      reply index

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-04-18  6:44 syzbot
2020-08-02 14:58 ` syzbot [this message]

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=00000000000075030605abe640e5@google.com \
    --to=syzbot+2e9900a1e1b3c9c96a77@syzkaller.appspotmail.com \
    --cc=davem@davemloft.net \
    --cc=hdanton@sina.com \
    --cc=johan.hedberg@gmail.com \
    --cc=kuba@kernel.org \
    --cc=linux-bluetooth@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=marcel@holtmann.org \
    --cc=netdev@vger.kernel.org \
    --cc=syzkaller-bugs@googlegroups.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

Linux-Bluetooth Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/linux-bluetooth/0 linux-bluetooth/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 linux-bluetooth linux-bluetooth/ https://lore.kernel.org/linux-bluetooth \
		linux-bluetooth@vger.kernel.org
	public-inbox-index linux-bluetooth

Example config snippet for mirrors

Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.kernel.vger.linux-bluetooth


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git