WARNING in v4l2_ctrl_auto_cluster

Status: upstream: reported C repro on 2026/09/08 22:08
Subsystems: media
Labels: prio:high
[Documentation on labels]
Reported-by: syzbot+cf896de36144391bcde1@syzkaller.appspotmail.com
Fix commit: 9ff738f93084 media: v4l2-ctrls: do nothing if controls[0] == NULL in cluster functions
Patched on: [ci-qemu-gce-upstream-auto ci-qemu-upstream ci-qemu-upstream-386 ci-qemu2-arm32 ci-qemu2-arm64 ci-qemu2-arm64-compat ci-qemu2-arm64-mte ci-snapshot-upstream-root ci-upstream-gce-leak ci-upstream-kasan-badwrites-root ci-upstream-kasan-gce ci-upstream-kasan-gce-386 ci-upstream-kasan-gce-root ci-upstream-kasan-gce-selinux-root ci-upstream-kasan-gce-smack-root ci-upstream-linux-next-kasan-gce-root ci-upstream-rust-kasan-gce ci2-upstream-fs ci2-upstream-kcsan-gce ci2-upstream-usb], missing on: [ci-qemu-native-arm64-kvm ci-qemu2-riscv64 ci-upstream-bpf-kasan-gce ci-upstream-bpf-next-kasan-gce ci-upstream-gce-arm64 ci-upstream-kmsan-gce-386-root ci-upstream-kmsan-gce-root ci-upstream-net-kasan-gce ci-upstream-net-this-kasan-gce]
First crash: 48d, last: 1d08h
▶ ▼ ✨ AI Patch Versions (1)
Version Stage Reported Report Link Job
1 moderation 2026/09/09 21:26 Discussion b5f6d956-eb5a-4244-a774-4b9f4cf9a078
▶ ▼ ✨ AI Jobs (2)
ID Workflow Result Correct Bug Created Started Finished Revision
b5f6d956 patching ❓ WARNING in v4l2_ctrl_auto_cluster 2026/09/09 16:07 2026/09/09 16:07 2026/09/09 21:26 b31349d1
dda73f2a assessment-security DenialOfService: ✅ Exploitable: ❌ FilesystemTrigger: ❌ NetworkTrigger: ❌ PeripheralTrigger: ✅ RemoteTrigger: ❌ Unprivileged: ❌ UserNamespace: ❌ VMGuestTrigger: ❌ VMHostTrigger: ❌ ❓ WARNING in v4l2_ctrl_auto_cluster 2026/09/09 00:00 2026/09/09 00:00 2026/09/09 00:49 243b72f1
▶ ▼ Discussions (9)
Title Replies (including bot) Last reply
[PATCH v3] media: v4l2-ctrls: do nothing if controls[0] == NULL in cluster functions 4 (4) 2026/09/23 07:21
[PATCH v3] media: v4l2-ctrls: do nothing if controls[0] == NULL in cluster functions 1 (1) 2026/09/19 02:11
Re: Delivery Status Notification (Failure) 1 (1) 2026/09/17 03:57
[PATCH v3] media: v4l2-ctrls: do nothing if controls[0] == NULL in cluster functions 1 (1) 2026/09/17 03:42
[PATCH v3] media: v4l2-ctrls: do nothing if controls[0] == NULL in cluster functions 1 (1) 2026/09/11 13:33
[PATCH v2] media: hackrf: defer v4l2_ctrl_auto_cluster() until after error check 3 (3) 2026/09/11 09:42
[PATCH v2] media: hackrf: defer v4l2_ctrl_auto_cluster() until after error check 1 (1) 2026/09/10 12:34
Fwd: [PATCH] media: hackrf: defer v4l2_ctrl_auto_cluster() until after error check 1 (1) 2026/09/09 17:04
[syzbot] [media?] [usb?] WARNING in v4l2_ctrl_auto_cluster 0 (1) 2026/09/08 22:08

Sample crash report:
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000002
R13: 00007f81ee626038 R14: 00007f81ee625fa0 R15: 00007ffd680b1ea8
 </TASK>
------------[ cut here ]------------
ncontrols == 0 || controls[0] == NULL
WARNING: drivers/media/v4l2-core/v4l2-ctrls-core.c:2525 at v4l2_ctrl_cluster drivers/media/v4l2-core/v4l2-ctrls-core.c:2525 [inline], CPU#0: syz.2.26/5734
WARNING: drivers/media/v4l2-core/v4l2-ctrls-core.c:2525 at v4l2_ctrl_auto_cluster+0x1c1/0x610 drivers/media/v4l2-core/v4l2-ctrls-core.c:2547, CPU#0: syz.2.26/5734
Modules linked in:
CPU: 0 UID: 0 PID: 5734 Comm: syz.2.26 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
RIP: 0010:v4l2_ctrl_cluster drivers/media/v4l2-core/v4l2-ctrls-core.c:2525 [inline]
RIP: 0010:v4l2_ctrl_auto_cluster+0x1c1/0x610 drivers/media/v4l2-core/v4l2-ctrls-core.c:2547
Code: ff c7 e9 e8 fe ff ff 89 e9 80 e1 07 80 c1 03 38 c1 0f 8c 73 ff ff ff 48 89 ef e8 da b1 22 fa e9 66 ff ff ff e8 a0 12 b1 f9 90 <0f> 0b 90 eb 65 e8 95 12 b1 f9 48 8b 44 24 28 80 3c 18 00 74 08 4c
RSP: 0018:ffffc9000760f7d8 EFLAGS: 00010293
RAX: ffffffff8816c3c0 RBX: dffffc0000000000 RCX: ffff888033ce8000
RDX: 0000000000000000 RSI: 0000000000000002 RDI: 0000000000000000
RBP: 0000000000000000 R08: ffffffff8ce09500 R09: 0000000000000001
R10: 0000000000000009 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: ffff888051a45628 R15: 0000000000000002
FS:  00007f81ef2da6c0(0000) GS:ffff88808c2ca000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007faf8e1eb840 CR3: 0000000043b66000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 hackrf_probe+0x80a/0x1360 drivers/media/usb/hackrf/hackrf.c:1430
 usb_probe_interface+0x788/0xe50 drivers/usb/core/driver.c:399
 call_driver_probe drivers/base/dd.c:-1 [inline]
 really_probe+0x254/0xae0 drivers/base/dd.c:706
 __driver_probe_device+0x1e8/0x360 drivers/base/dd.c:868
 driver_probe_device+0x4f/0x240 drivers/base/dd.c:898
 __device_attach_driver+0x270/0x410 drivers/base/dd.c:1026
 bus_for_each_drv+0x258/0x2f0 drivers/base/bus.c:500
 __device_attach+0x2c4/0x450 drivers/base/dd.c:1098
 proc_ioctl+0x409/0x660 drivers/usb/core/devio.c:2370
 proc_ioctl_default+0xc4/0x110 drivers/usb/core/devio.c:2405
 usbdev_do_ioctl drivers/usb/core/devio.c:2769 [inline]
 usbdev_ioctl+0x1386/0x2120 drivers/usb/core/devio.c:2829
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:597 [inline]
 __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f81ee39e159
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f81ef2da028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f81ee625fa0 RCX: 00007f81ee39e159
RDX: 0000200000000200 RSI: 00000000c0105512 RDI: 0000000000000004
RBP: 00007f81ef2da090 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000002
R13: 00007f81ee626038 R14: 00007f81ee625fa0 R15: 00007ffd680b1ea8
 </TASK>

Crashes (4):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/09/08 04:42 upstream 28924df2a08f 680aa3e1 .config console log report syz / log C [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in v4l2_ctrl_auto_cluster
2026/10/25 08:30 upstream 330517c63aa9 1d9ca40b .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in v4l2_ctrl_auto_cluster
2026/09/16 04:50 upstream f6e7b42bf05b 12a0a44a .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in v4l2_ctrl_auto_cluster
2026/09/08 03:29 upstream 28924df2a08f 680aa3e1 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in v4l2_ctrl_auto_cluster
* Struck through repros no longer work on HEAD.