WARNING in pvr2_hdw_create

Status: upstream: reported on 2026/08/02 13:40
Subsystems: pvrusb2
Labels: prio:low
[Documentation on labels]
Reported-by: syzbot+b91abe6ef9924496daf8@syzkaller.appspotmail.com
First crash: 97d, last: 97d
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ID Workflow Result Correct Bug Created Started Finished Revision
a9bfef8e assessment-security DenialOfService: ❌ Exploitable: ❌ FilesystemTrigger: ❌ NetworkTrigger: ❌ PeripheralTrigger: ✅ RemoteTrigger: ❌ Unprivileged: ❌ UserNamespace: ❌ VMGuestTrigger: ❌ VMHostTrigger: ❌ ❓ WARNING in pvr2_hdw_create 2026/07/31 02:44 2026/07/31 02:44 2026/07/31 02:46 aaffb173
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Title Replies (including bot) Last reply
[syzbot] [pvrusb2?] WARNING in pvr2_hdw_create 0 (1) 2026/08/02 13:40

Sample crash report:
pvrusb2: ***WARNING*** Support for this device (Terratec Grabster AV400) is experimental.
pvrusb2: Important functionality might not be entirely working.
pvrusb2: Please consider contacting the driver author to help with further stabilization of the driver.
pvrusb2: **********
FAULT_INJECTION: forcing a failure.
name failslab, interval 1, probability 1, space 0, times 950
CPU: 0 UID: 0 PID: 5302 Comm: kworker/0:4 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
Workqueue: usb_hub_wq hub_event
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
 fail_dump lib/fault-inject.c:73 [inline]
 should_fail_ex+0x40c/0x560 lib/fault-inject.c:174
 should_failslab+0xa8/0x100 mm/failslab.c:46
 slab_pre_alloc_hook mm/slub.c:4539 [inline]
 slab_alloc_node mm/slub.c:4897 [inline]
 __kmalloc_cache_noprof+0xa8/0x660 mm/slub.c:5485
 _kmalloc_noprof include/linux/slab.h:988 [inline]
 pvr2_hdw_create+0x1e6b/0x3030 drivers/media/usb/pvrusb2/pvrusb2-hdw.c:2545
 pvr2_context_create+0x18b/0x380 drivers/media/usb/pvrusb2/pvrusb2-context.c:222
 pvr_probe+0x25/0xd0 drivers/media/usb/pvrusb2/pvrusb2-main.c:54
 usb_probe_interface+0x653/0xc60 drivers/usb/core/driver.c:396
 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
 device_initial_probe+0xa1/0xd0 drivers/base/dd.c:1153
 bus_probe_device+0x12a/0x220 drivers/base/bus.c:620
 device_add+0x7d7/0xb80 drivers/base/core.c:3772
 usb_set_configuration+0x1ad8/0x2180 drivers/usb/core/message.c:2268
 usb_generic_driver_probe+0x8d/0x150 drivers/usb/core/generic.c:250
 usb_probe_device+0x1c3/0x3b0 drivers/usb/core/driver.c:291
 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
 device_initial_probe+0xa1/0xd0 drivers/base/dd.c:1153
 bus_probe_device+0x12a/0x220 drivers/base/bus.c:620
 device_add+0x7d7/0xb80 drivers/base/core.c:3772
 usb_new_device+0x99d/0x1620 drivers/usb/core/hub.c:2695
 hub_port_connect drivers/usb/core/hub.c:5567 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5707 [inline]
 port_event drivers/usb/core/hub.c:5871 [inline]
 hub_event+0x28e8/0x4d30 drivers/usb/core/hub.c:5953
 process_one_work kernel/workqueue.c:3322 [inline]
 process_scheduled_works+0xa8e/0x14e0 kernel/workqueue.c:3405
 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3486
 kthread+0x388/0x470 kernel/kthread.c:436
 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
------------[ cut here ]------------
!work->func
WARNING: kernel/workqueue.c:4335 at __flush_work+0xb8f/0xca0 kernel/workqueue.c:4335, CPU#0: kworker/0:4/5302
Modules linked in:
CPU: 0 UID: 0 PID: 5302 Comm: kworker/0:4 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
Workqueue: usb_hub_wq hub_event
RIP: 0010:__flush_work+0xb8f/0xca0 kernel/workqueue.c:4335
Code: 75 5e 48 8d 65 d8 5b 41 5c 41 5d 41 5e 41 5f 5d e9 46 c3 47 0a cc e8 f0 df 38 00 90 0f 0b 90 e9 7c ff ff ff e8 e2 df 38 00 90 <0f> 0b 90 31 c0 48 bb f8 f8 f8 f8 f8 f8 f8 f8 e9 64 ff ff ff e8 c8
RSP: 0018:ffffc9000de06ac0 EFLAGS: 00010293
RAX: ffffffff818e346e RBX: ffff88805194c0e8 RCX: ffff88801fb78000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff88805194c0d0
RBP: ffffc9000de06c70 R08: ffffffff9057b737 R09: 1ffffffff20af6e6
R10: dffffc0000000000 R11: fffffbfff20af6e7 R12: dffffc0000000000
R13: 1ffff1100a32981d R14: 1ffff92001bc0d60 R15: ffff88805194c0d0
FS:  0000000000000000(0000) GS:ffff88808c543000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fcb17bd60f5 CR3: 00000000437d3000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 pvr2_hdw_create+0x207f/0x3030 drivers/media/usb/pvrusb2/pvrusb2-hdw.c:2610
 pvr2_context_create+0x18b/0x380 drivers/media/usb/pvrusb2/pvrusb2-context.c:222
 pvr_probe+0x25/0xd0 drivers/media/usb/pvrusb2/pvrusb2-main.c:54
 usb_probe_interface+0x653/0xc60 drivers/usb/core/driver.c:396
 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
 device_initial_probe+0xa1/0xd0 drivers/base/dd.c:1153
 bus_probe_device+0x12a/0x220 drivers/base/bus.c:620
 device_add+0x7d7/0xb80 drivers/base/core.c:3772
 usb_set_configuration+0x1ad8/0x2180 drivers/usb/core/message.c:2268
 usb_generic_driver_probe+0x8d/0x150 drivers/usb/core/generic.c:250
 usb_probe_device+0x1c3/0x3b0 drivers/usb/core/driver.c:291
 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
 device_initial_probe+0xa1/0xd0 drivers/base/dd.c:1153
 bus_probe_device+0x12a/0x220 drivers/base/bus.c:620
 device_add+0x7d7/0xb80 drivers/base/core.c:3772
 usb_new_device+0x99d/0x1620 drivers/usb/core/hub.c:2695
 hub_port_connect drivers/usb/core/hub.c:5567 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5707 [inline]
 port_event drivers/usb/core/hub.c:5871 [inline]
 hub_event+0x28e8/0x4d30 drivers/usb/core/hub.c:5953
 process_one_work kernel/workqueue.c:3322 [inline]
 process_scheduled_works+0xa8e/0x14e0 kernel/workqueue.c:3405
 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3486
 kthread+0x388/0x470 kernel/kthread.c:436
 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/07/29 13:28 upstream fc02acf6ac0c b63596d1 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in pvr2_hdw_create
* Struck through repros no longer work on HEAD.