general protection fault in usbtv_querycap

Status: moderation: reported on 2026/08/02 10:55
Subsystems: media
[Documentation on labels]
Reported-by: syzbot+abe640a8eb436924acf3@syzkaller.appspotmail.com
First crash: 5d02h, last: 5d02h
✨ AI Jobs (2)
ID Workflow Result Correct Bug Created Started Finished Revision Error
2b870755 assessment-security 💥 general protection fault in usbtv_querycap 2026/08/02 01:38 2026/08/02 01:38 2026/08/02 01:38 e611ffe1
dashboard requested TargetOS "linux" TargetArch "386", but agent does not support it
ad282ab7 assessment-security 💥 general protection fault in usbtv_querycap 2026/07/31 02:04 2026/07/31 02:04 2026/07/31 02:04 aaffb173
dashboard requested TargetOS "linux" TargetArch "386", but agent does not support it

Sample crash report:
Oops: general protection fault, probably for non-canonical address 0xdffffc000000000a: 0000 [#1] SMP KASAN PTI
KASAN: null-ptr-deref in range [0x0000000000000050-0x0000000000000057]
CPU: 1 UID: 0 PID: 24737 Comm: v4l_id Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
RIP: 0010:usb_make_path include/linux/usb.h:985 [inline]
RIP: 0010:usbtv_querycap+0x9c/0x100 drivers/media/usb/usbtv/usbtv-video.c:612
Code: d7 f9 49 83 c6 08 4c 89 f0 48 c1 e8 03 42 80 3c 20 00 74 08 4c 89 f7 e8 c2 2c d7 f9 4d 8b 36 4d 8d 7e 50 4c 89 f8 48 c1 e8 03 <42> 80 3c 20 00 74 08 4c 89 ff e8 a5 2c d7 f9 48 83 c3 30 4d 8b 3f
RSP: 0000:ffffc90004f5fb10 EFLAGS: 00010206
RAX: 000000000000000a RBX: ffffc90004f5fd60 RCX: 0000000074627375
RDX: 0000000000000006 RSI: ffffffff8cd18a40 RDI: ffffc90004f5fd70
RBP: 1ffff920009ebfb6 R08: 0000000000767462 R09: 1ffff920009ebfae
R10: dffffc0000000000 R11: fffff520009ebfaf R12: dffffc0000000000
R13: ffff888020b3a0d8 R14: 0000000000000000 R15: 0000000000000050
FS:  00007f506ab68880(0000) GS:ffff88812504e000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055b880b1b64d CR3: 0000000021750000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 v4l_querycap+0x236/0x470 drivers/media/v4l2-core/v4l2-ioctl.c:1106
 __video_do_ioctl+0x8af/0xc70 drivers/media/v4l2-core/v4l2-ioctl.c:3133
 video_usercopy+0x860/0x1430 drivers/media/v4l2-core/v4l2-ioctl.c:3475
 v4l2_ioctl+0x18d/0x1e0 drivers/media/v4l2-core/v4l2-dev.c:366
 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:63 [inline]
 do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f506a51d378
Code: 00 00 48 8d 44 24 08 48 89 54 24 e0 48 89 44 24 c0 48 8d 44 24 d0 48 89 44 24 c8 b8 10 00 00 00 c7 44 24 b8 10 00 00 00 0f 05 <89> c2 3d 00 f0 ff ff 77 07 89 d0 c3 0f 1f 40 00 48 8b 15 49 3a 0d
RSP: 002b:00007ffe752fd5e8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f506a51d378
RDX: 00007ffe752fd5f0 RSI: 0000000080685600 RDI: 0000000000000003
RBP: 0000000000000002 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffe752fd7a0 R14: 00007f506ac6d000 R15: 000055b880b1f4d8
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:usb_make_path include/linux/usb.h:985 [inline]
RIP: 0010:usbtv_querycap+0x9c/0x100 drivers/media/usb/usbtv/usbtv-video.c:612
Code: d7 f9 49 83 c6 08 4c 89 f0 48 c1 e8 03 42 80 3c 20 00 74 08 4c 89 f7 e8 c2 2c d7 f9 4d 8b 36 4d 8d 7e 50 4c 89 f8 48 c1 e8 03 <42> 80 3c 20 00 74 08 4c 89 ff e8 a5 2c d7 f9 48 83 c3 30 4d 8b 3f
RSP: 0000:ffffc90004f5fb10 EFLAGS: 00010206
RAX: 000000000000000a RBX: ffffc90004f5fd60 RCX: 0000000074627375
RDX: 0000000000000006 RSI: ffffffff8cd18a40 RDI: ffffc90004f5fd70
RBP: 1ffff920009ebfb6 R08: 0000000000767462 R09: 1ffff920009ebfae
R10: dffffc0000000000 R11: fffff520009ebfaf R12: dffffc0000000000
R13: ffff888020b3a0d8 R14: 0000000000000000 R15: 0000000000000050
FS:  00007f506ab68880(0000) GS:ffff88812504e000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000581d821c CR3: 0000000021750000 CR4: 00000000003526f0
----------------
Code disassembly (best guess):
   0:	d7                   	xlat   %ds:(%rbx)
   1:	f9                   	stc
   2:	49 83 c6 08          	add    $0x8,%r14
   6:	4c 89 f0             	mov    %r14,%rax
   9:	48 c1 e8 03          	shr    $0x3,%rax
   d:	42 80 3c 20 00       	cmpb   $0x0,(%rax,%r12,1)
  12:	74 08                	je     0x1c
  14:	4c 89 f7             	mov    %r14,%rdi
  17:	e8 c2 2c d7 f9       	call   0xf9d72cde
  1c:	4d 8b 36             	mov    (%r14),%r14
  1f:	4d 8d 7e 50          	lea    0x50(%r14),%r15
  23:	4c 89 f8             	mov    %r15,%rax
  26:	48 c1 e8 03          	shr    $0x3,%rax
* 2a:	42 80 3c 20 00       	cmpb   $0x0,(%rax,%r12,1) <-- trapping instruction
  2f:	74 08                	je     0x39
  31:	4c 89 ff             	mov    %r15,%rdi
  34:	e8 a5 2c d7 f9       	call   0xf9d72cde
  39:	48 83 c3 30          	add    $0x30,%rbx
  3d:	4d 8b 3f             	mov    (%r15),%r15

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/07/29 10:47 upstream fc02acf6ac0c 19622d9d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-386 general protection fault in usbtv_querycap
* Struck through repros no longer work on HEAD.