syzbot


WARNING in media_create_pad_link (2)

Status: upstream: reported on 2026/03/17 03:30
Reported-by: syzbot+e9468c825031b925db7b@syzkaller.appspotmail.com
First crash: 1d06h, last: 1d06h
Similar bugs (5)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-5.15 WARNING in media_create_pad_link (2) -1 C 3 17m 1d08h 0/3 upstream: reported C repro on 2026/03/17 02:25
upstream WARNING in media_create_pad_link (2) usb media -1 C error done 11 161d 364d 29/29 fixed on 2025/11/14 14:05
linux-5.15 WARNING in media_create_pad_link origin:upstream -1 C error 7 461d 1094d 0/3 auto-obsoleted due to no activity on 2025/03/22 03:16
linux-6.1 WARNING in media_create_pad_link origin:upstream -1 C error 2 562d 1094d 3/3 fixed on 2024/12/14 20:01
upstream WARNING in media_create_pad_link usb media -1 C done done 104 481d 2133d 28/29 fixed on 2024/12/16 09:50

Sample crash report:
uvcvideo 3-1:6.220: Entity type for entity Output 4 was not initialized!
------------[ cut here ]------------
WARNING: CPU: 1 PID: 4313 at drivers/media/mc/mc-entity.c:1069 media_create_pad_link+0x9ec/0xb80 drivers/media/mc/mc-entity.c:1069
Modules linked in:
CPU: 1 PID: 4313 Comm: kworker/1:5 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Workqueue: usb_hub_wq hub_event
RIP: 0010:media_create_pad_link+0x9ec/0xb80 drivers/media/mc/mc-entity.c:1069
Code: 01 00 00 66 ff 03 31 c0 48 83 c4 70 5b 41 5c 41 5d 41 5e 41 5f 5d c3 e8 92 86 c4 fa 0f 0b b8 ea ff ff ff eb e3 e8 84 86 c4 fa <0f> 0b b8 ea ff ff ff eb d5 e8 76 86 c4 fa 0f 0b b8 ea ff ff ff eb
RSP: 0000:ffffc900041a6ab8 EFLAGS: 00010287
RAX: ffffffff86bdec2c RBX: 0000000000000002 RCX: 0000000000100000
RDX: ffffc9001b15b000 RSI: 000000000002cd6b RDI: 000000000002cd6c
RBP: 0000000000000000 R08: 0000000000000003 R09: 1ffff1100ef4c697
R10: dffffc0000000000 R11: ffffed100ef4c698 R12: ffff88807ccb80b8
R13: ffff88807ccb8080 R14: 0000000000000003 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f2079735bdf CR3: 0000000026828000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 uvc_mc_create_links drivers/media/usb/uvc/uvc_entity.c:50 [inline]
 uvc_mc_register_entities+0x725/0x9d0 drivers/media/usb/uvc/uvc_entity.c:151
 uvc_register_chains+0x3cf/0x4b0 drivers/media/usb/uvc/uvc_driver.c:2094
 uvc_probe+0xa0bc/0xad20 drivers/media/usb/uvc/uvc_driver.c:2239
 usb_probe_interface+0x5c5/0xb20 drivers/usb/core/driver.c:396
 call_driver_probe drivers/base/dd.c:-1 [inline]
 really_probe+0x2aa/0xc70 drivers/base/dd.c:639
 __driver_probe_device+0x18c/0x330 drivers/base/dd.c:785
 driver_probe_device+0x4f/0x420 drivers/base/dd.c:815
 __device_attach_driver+0x2c6/0x510 drivers/base/dd.c:943
 bus_for_each_drv+0x184/0x210 drivers/base/bus.c:429
 __device_attach+0x2a8/0x480 drivers/base/dd.c:1015
 bus_probe_device+0xbc/0x1e0 drivers/base/bus.c:489
 device_add+0xa00/0xfb0 drivers/base/core.c:3697
 usb_set_configuration+0x1991/0x1fd0 drivers/usb/core/message.c:2165
 usb_generic_driver_probe+0x89/0x150 drivers/usb/core/generic.c:238
 usb_probe_device+0x139/0x270 drivers/usb/core/driver.c:293
 call_driver_probe drivers/base/dd.c:-1 [inline]
 really_probe+0x2aa/0xc70 drivers/base/dd.c:639
 __driver_probe_device+0x18c/0x330 drivers/base/dd.c:785
 driver_probe_device+0x4f/0x420 drivers/base/dd.c:815
 __device_attach_driver+0x2c6/0x510 drivers/base/dd.c:943
 bus_for_each_drv+0x184/0x210 drivers/base/bus.c:429
 __device_attach+0x2a8/0x480 drivers/base/dd.c:1015
 bus_probe_device+0xbc/0x1e0 drivers/base/bus.c:489
 device_add+0xa00/0xfb0 drivers/base/core.c:3697
 usb_new_device+0xd66/0x1650 drivers/usb/core/hub.c:2659
 hub_port_connect drivers/usb/core/hub.c:5517 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5657 [inline]
 port_event drivers/usb/core/hub.c:5817 [inline]
 hub_event+0x2dcf/0x5560 drivers/usb/core/hub.c:5899
 process_one_work+0x8a2/0x1160 kernel/workqueue.c:2292
 worker_thread+0xaa2/0x1270 kernel/workqueue.c:2439
 kthread+0x29d/0x330 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/03/17 03:29 linux-6.1.y f2ddafa93a25 0737c18f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in media_create_pad_link
2026/03/17 03:29 linux-6.1.y f2ddafa93a25 0737c18f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in media_create_pad_link
* Struck through repros no longer work on HEAD.