WARNING in hci_conn_timeout (2)

Status: upstream: reported C repro on 2024/12/17 17:47
Subsystems: bluetooth
Labels: prio:low
[Documentation on labels]
Reported-by: syzbot+fc4b5b2477d4ca272907@syzkaller.appspotmail.com
First crash: 610d, last: 10m
Cause bisection: failed (error log, bisect log)
  
✨ AI Jobs (2)
ID Workflow Result Correct Bug Created Started Finished Revision
a945ef85 assessment-security DenialOfService: ❌ Exploitable: ❌ FilesystemTrigger: ❌ NetworkTrigger: ❌ PeripheralTrigger: ✅ RemoteTrigger: ❌ Unprivileged: ❌ UserNamespace: ❌ VMGuestTrigger: ❌ VMHostTrigger: ❌ WARNING in hci_conn_timeout (2) 2026/05/21 07:09 2026/05/21 07:09 2026/05/21 07:59 cf874a1c
91e94c49 patching-compressed 💥 WARNING in hci_conn_timeout (2) 2026/05/10 09:20 2026/05/10 20:39 2026/05/10 23:23 29233ece
Discussions (17)
Title Replies (including bot) Last reply
[syzbot] Monthly bluetooth report (May 2026) 0 (1) 2026/05/02 12:32
[syzbot] Monthly bluetooth report (Apr 2026) 0 (1) 2026/04/01 07:42
[syzbot] Monthly bluetooth report (Mar 2026) 0 (1) 2026/03/01 06:23
[syzbot] Monthly bluetooth report (Jan 2026) 0 (1) 2026/01/28 22:38
[syzbot] Monthly bluetooth report (Dec 2025) 0 (1) 2025/12/29 08:12
[syzbot] Monthly bluetooth report (Nov 2025) 0 (1) 2025/11/27 12:42
[syzbot] Monthly bluetooth report (Oct 2025) 0 (1) 2025/10/27 05:54
[syzbot] Monthly bluetooth report (Sep 2025) 0 (1) 2025/09/24 12:39
[syzbot] Monthly bluetooth report (Aug 2025) 0 (1) 2025/08/25 08:44
[syzbot] Monthly bluetooth report (Jul 2025) 0 (1) 2025/07/24 09:32
[syzbot] Monthly bluetooth report (Jun 2025) 0 (1) 2025/06/23 07:31
[syzbot] Monthly bluetooth report (May 2025) 0 (1) 2025/05/22 12:58
[syzbot] Monthly bluetooth report (Apr 2025) 0 (1) 2025/04/22 10:11
[syzbot] Monthly bluetooth report (Mar 2025) 0 (1) 2025/03/20 23:48
[syzbot] Monthly bluetooth report (Feb 2025) 0 (1) 2025/02/17 12:44
[syzbot] Monthly bluetooth report (Jan 2025) 0 (1) 2025/01/17 10:35
[syzbot] [bluetooth?] WARNING in hci_conn_timeout (2) 0 (1) 2024/12/17 17:47
Similar bugs (6)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream WARNING in hci_conn_timeout bluetooth -1 syz, C done 6022 610d 2208d 28/29 fixed on 2024/12/16 09:50
linux-5.15 WARNING in hci_conn_timeout origin:lts-only -1 syz, C done 1493 1d19h 1257d 0/3 upstream: reported C repro on 2023/03/10 14:50
linux-4.14 WARNING in hci_conn_timeout -1 syz, C inconclusive 27 1275d 2209d 0/1 upstream: reported C repro on 2020/07/31 02:13
linux-6.6 WARNING in hci_conn_timeout origin:lts-only -1 syz, C inconclusive 44 21d 419d 0/2 upstream: reported C repro on 2025/06/25 01:13
linux-4.19 WARNING in hci_conn_timeout -1 syz, C error 127 1262d 2208d 0/1 upstream: reported C repro on 2020/08/01 17:09
linux-6.1 WARNING in hci_conn_timeout origin:lts-only -1 syz, C done 6549 3h45m 1259d 0/3 upstream: reported C repro on 2023/03/08 17:34

Sample crash report:
kobject: kobject_add_internal failed for hci0:0 with -EEXIST, don't try to register things with the same name in the same directory.
Bluetooth: hci0: failed to register connection device
------------[ cut here ]------------
refcnt < 0
WARNING: net/bluetooth/hci_conn.c:631 at hci_conn_timeout+0x16a/0x230 net/bluetooth/hci_conn.c:631, CPU#0: kworker/u9:1/4941
Modules linked in:
CPU: 0 UID: 0 PID: 4941 Comm: kworker/u9:1 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Workqueue: hci0 hci_conn_timeout
RIP: 0010:hci_conn_timeout+0x16a/0x230 net/bluetooth/hci_conn.c:631
Code: 44 0f b6 2d 8b e4 6e 06 31 ff 41 83 e5 40 44 89 ee e8 4a 6c 5a f7 45 84 ed 0f 84 02 ff ff ff e9 f7 27 c2 f6 e8 27 72 5a f7 90 <0f> 0b 90 e8 1e 72 5a f7 48 8d bb fd f5 ff ff 48 b8 00 00 00 00 00
RSP: 0018:ffffc9000614fc18 EFLAGS: 00010293
RAX: 0000000000000000 RBX: ffff88802cbf0a40 RCX: ffffffff8aaf393f
RDX: ffff888036be8000 RSI: ffffffff8aaf3a39 RDI: ffff888036be8000
RBP: 00000000ffffffff R08: 0000000000000005 R09: 0000000000000000
R10: 00000000ffffffff R11: 000000000000756b R12: ffff88802cbf0000
R13: ffff888036be84c4 R14: ffffffff9122d684 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff888123de3000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b30b63fff CR3: 0000000074a54000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 process_one_work+0xa23/0x1940 kernel/workqueue.c:3322
 process_scheduled_works kernel/workqueue.c:3405 [inline]
 worker_thread+0x5ef/0xe50 kernel/workqueue.c:3486
 kthread+0x370/0x450 kernel/kthread.c:436
 ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>

Crashes (26000):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/07/30 17:02 upstream 11028ab62899 abc81b93 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in hci_conn_timeout
2026/05/25 08:15 upstream 6a97c4d5262d c69befb3 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING in hci_conn_timeout
2025/11/04 13:55 upstream 8bb886cb8f3a 686bf657 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root WARNING in hci_conn_timeout
2024/12/18 09:16 upstream aef25be35d23 a0626d3a .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in hci_conn_timeout
2024/12/17 12:45 upstream f44d154d6e3d f93b2b55 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING in hci_conn_timeout
2026/07/28 09:42 upstream 62cc90241548 4a865b71 .config console log report syz / log C [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in hci_conn_timeout
2025/07/09 16:27 upstream 733923397fd9 956bd956 .config console log report syz / log C [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in hci_conn_timeout
2025/02/26 18:57 upstream ac9c34d1e45a 6a8fcbc4 .config console log report syz / log C [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in hci_conn_timeout
2025/11/14 06:56 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci db9030a787e3 07e030de .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in hci_conn_timeout
2024/12/31 15:39 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 573067a5a685 d3ccff63 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in hci_conn_timeout
2026/03/12 17:31 upstream 80234b5ab240 4efadf07 .config console log report syz / log [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in hci_conn_timeout
2025/07/13 10:33 upstream 3f31a806a62e 3cda49cf .config console log report syz / log [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in hci_conn_timeout
2025/03/04 21:34 upstream 99fa936e8e4f c3901742 .config console log report syz / log [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root WARNING in hci_conn_timeout
2025/01/19 10:37 upstream fda5e3f28400 f2cb035c .config console log report syz / log [disk image] [vmlinux] [kernel image] ci-upstream-kasan-badwrites-root WARNING in hci_conn_timeout
2025/12/14 02:24 linux-next d9771d0dbe18 d6526ea3 .config console log report syz / log [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root WARNING in hci_conn_timeout
2025/02/06 04:43 linux-next ed88b8b82c53 577d049b .config console log report syz / log [disk image] [vmlinux] [kernel image] [mounted in repro] ci-upstream-linux-next-kasan-gce-root WARNING in hci_conn_timeout
2026/08/03 11:35 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 7235a3e71949 e611ffe1 .config console log report syz / log [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in hci_conn_timeout
2026/08/18 19:02 upstream 0f23d56f17fd 1e72964b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in hci_conn_timeout
2026/08/18 13:15 upstream 0f23d56f17fd 1e72964b .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in hci_conn_timeout
2026/08/18 11:07 upstream ff68e5f557f6 1e72964b .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in hci_conn_timeout
2026/08/18 00:08 upstream ff68e5f557f6 1e72964b .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in hci_conn_timeout
2026/08/17 21:42 upstream 8d3ae59288f1 1e72964b .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in hci_conn_timeout
2026/08/17 09:35 upstream 8d3ae59288f1 905244d6 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in hci_conn_timeout
2026/08/17 08:29 upstream 8d3ae59288f1 746171ee .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in hci_conn_timeout
2026/08/16 23:36 upstream dcb68831eac7 746171ee .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in hci_conn_timeout
2026/08/16 19:06 upstream dcb68831eac7 746171ee .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in hci_conn_timeout
2026/08/16 11:34 upstream 3eb40771c00a 746171ee .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in hci_conn_timeout
2026/08/16 11:19 upstream 3eb40771c00a 746171ee .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in hci_conn_timeout
2026/08/16 01:56 upstream 3eb40771c00a 746171ee .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in hci_conn_timeout
2026/08/15 23:15 upstream 3eb40771c00a 746171ee .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root WARNING in hci_conn_timeout
2026/08/15 22:09 upstream 3eb40771c00a 746171ee .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in hci_conn_timeout
2026/08/15 22:09 upstream 3eb40771c00a 746171ee .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in hci_conn_timeout
2026/08/15 12:45 upstream 15ef2f78c49d 746171ee .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in hci_conn_timeout
2026/08/15 07:43 upstream 2f1baf1fc892 746171ee .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in hci_conn_timeout
2026/08/14 23:34 upstream a5161661ae99 746171ee .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in hci_conn_timeout
2026/08/14 18:37 upstream 2f1baf1fc892 746171ee .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in hci_conn_timeout
2026/08/12 20:27 upstream 3d6d817622b0 7ae4acc7 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING in hci_conn_timeout
2026/08/09 08:22 upstream 06cf61899d64 5d63f80b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-badwrites-root WARNING in hci_conn_timeout
2026/08/01 19:35 upstream 0131b508c0e2 e611ffe1 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-386 WARNING in hci_conn_timeout
2026/08/18 21:25 upstream 0f23d56f17fd 1e72964b .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in hci_conn_timeout
2026/08/18 16:55 upstream 0f23d56f17fd 1e72964b .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in hci_conn_timeout
2026/08/18 15:25 upstream 0f23d56f17fd 1e72964b .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in hci_conn_timeout
2026/08/18 12:10 upstream ff68e5f557f6 1e72964b .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in hci_conn_timeout
2026/08/18 10:34 upstream ff68e5f557f6 1e72964b .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in hci_conn_timeout
2026/08/18 03:29 upstream ff68e5f557f6 1e72964b .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in hci_conn_timeout
2026/08/17 15:54 upstream 8d3ae59288f1 905244d6 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in hci_conn_timeout
2026/08/17 01:23 upstream dcb68831eac7 746171ee .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in hci_conn_timeout
2026/08/16 16:43 upstream 3eb40771c00a 746171ee .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in hci_conn_timeout
2026/08/16 15:04 upstream 3eb40771c00a 746171ee .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in hci_conn_timeout
2026/08/16 12:59 upstream 3eb40771c00a 746171ee .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in hci_conn_timeout
2026/08/16 08:38 upstream 3eb40771c00a 746171ee .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in hci_conn_timeout
2026/08/16 07:30 upstream 3eb40771c00a 746171ee .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in hci_conn_timeout
2026/08/16 05:40 upstream 3eb40771c00a 746171ee .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in hci_conn_timeout
2026/08/16 00:18 upstream 15ef2f78c49d 746171ee .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in hci_conn_timeout
2026/08/15 19:08 upstream 15ef2f78c49d 746171ee .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in hci_conn_timeout
2026/08/15 16:30 upstream 15ef2f78c49d 746171ee .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in hci_conn_timeout
2026/08/15 09:09 upstream a5161661ae99 746171ee .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in hci_conn_timeout
2026/08/14 01:25 upstream 3aa1dcaa4f6f b13552fe .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 WARNING in hci_conn_timeout
2026/08/13 21:32 bpf a13307e97d5c a9ede23c .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-kasan-gce WARNING in hci_conn_timeout
2025/02/03 13:06 net 235174b2bed8 a21a8419 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce WARNING in hci_conn_timeout
2026/08/11 22:55 bpf-next 07cb86aa5081 37a258dd .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce WARNING in hci_conn_timeout
2025/03/13 12:32 net-next 0ea09cbf8350 44be8b44 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce WARNING in hci_conn_timeout
2026/08/18 07:41 linux-next e6664f2b33db 1e72964b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING in hci_conn_timeout
2026/08/17 17:32 linux-next 4477a78374a5 1e72964b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING in hci_conn_timeout
2026/08/11 10:53 linux-next 3d08ff75a47a 37a258dd .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root WARNING in hci_conn_timeout
2026/08/18 20:06 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 21d6ac051080 1e72964b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in hci_conn_timeout
2026/08/18 06:18 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 21d6ac051080 1e72964b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in hci_conn_timeout
2026/08/17 19:31 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 21d6ac051080 1e72964b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in hci_conn_timeout
2026/08/16 09:42 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 21d6ac051080 746171ee .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in hci_conn_timeout
2026/08/16 04:07 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 21d6ac051080 746171ee .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in hci_conn_timeout
2026/08/15 17:31 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 21d6ac051080 746171ee .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in hci_conn_timeout
2026/08/15 05:28 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 21d6ac051080 746171ee .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in hci_conn_timeout
2026/08/15 02:00 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 21d6ac051080 746171ee .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in hci_conn_timeout
2026/08/14 22:30 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 21d6ac051080 746171ee .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in hci_conn_timeout
2026/08/14 19:42 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 21d6ac051080 746171ee .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in hci_conn_timeout
2026/08/14 17:05 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 21d6ac051080 746171ee .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in hci_conn_timeout
* Struck through repros no longer work on HEAD.