WARNING in ttusb_start_feed/usb_submit_urb

Status: upstream: reported C repro on 2026/09/18 16:57
Subsystems: media usb
Labels: prio:high
[Documentation on labels]
Reported-by: syzbot+3caf6a60e5f9be12de08@syzkaller.appspotmail.com
First crash: 14h27m, last: 12h19m
✨ AI Jobs (1)
ID Workflow Result Correct Bug Created Started Finished Revision
5b8fc2b4 assessment-security DenialOfService: ✅ Exploitable: ✅ FilesystemTrigger: ❌ NetworkTrigger: ❌ PeripheralTrigger: ✅ RemoteTrigger: ❌ Unprivileged: ✅ UserNamespace: ❌ VMGuestTrigger: ✅ VMHostTrigger: ❌ WARNING in ttusb_start_feed/usb_submit_urb 2026/09/19 00:59 2026/09/19 00:59 2026/09/19 01:05 853b104b
Discussions (2)
Title Replies (including bot) Last reply
[PATCH] media: ttusb-budget: check the endpoints before using them 1 (1) 2026/09/18 20:33
[syzbot] [media?] [usb?] WARNING in ttusb_start_feed/usb_submit_urb 0 (1) 2026/09/18 16:57

Sample crash report:
usb 1-1: BOGUS urb xfer, pipe 0 != type 1
------------[ cut here ]------------
usb 1-1: BOGUS urb flags, 202 --> 200
WARNING: drivers/usb/core/urb.c:533 at usb_submit_urb+0xc9d/0x18b0 drivers/usb/core/urb.c:532, CPU#0: syz.0.17/5838
Modules linked in:
CPU: 0 UID: 0 PID: 5838 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
RIP: 0010:usb_submit_urb+0xd28/0x18b0 drivers/usb/core/urb.c:532
Code: e8 7d 79 c9 fa 4c 89 f7 4d 8b 6d 00 41 0f b6 04 2c 84 c0 48 8b 54 24 18 0f 85 97 07 00 00 8b 0a 48 8b 34 24 4c 89 ea 45 89 f8 <67> 48 0f b9 3a 4c 8b 6c 24 08 4c 89 ef 48 c7 c6 80 2b b0 8f e8 9f
RSP: 0018:ffffc9000395f918 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffff8880308f2000 RCX: 0000000000000202
RDX: ffff88807e689280 RSI: ffffffff8cc51f20 RDI: ffffffff9087dfb0
RBP: dffffc0000000000 R08: 0000000000000200 R09: 0000000000000004
R10: 0000000000000003 R11: 0000000000000000 R12: 1ffff1100611e40b
R13: ffff88807e689280 R14: ffff888031bba100 R15: 0000000000000200
FS:  0000000000000000(0000) GS:ffff888124cd2000(0063) knlGS:0000000057d95480
CS:  0010 DS: 002b ES: 002b CR0: 0000000080050033
CR2: 000055af9ae48058 CR3: 0000000078e3c000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 ttusb_start_iso_xfer drivers/media/usb/ttusb-budget/dvb-ttusb-budget.c:829 [inline]
 ttusb_start_feed+0xe19/0x1770 drivers/media/usb/ttusb-budget/dvb-ttusb-budget.c:899
 dmx_ts_feed_start_filtering+0x129/0x220 drivers/media/dvb-core/dvb_demux.c:747
 dvb_dmxdev_start_feed drivers/media/dvb-core/dmxdev.c:658 [inline]
 dvb_dmxdev_filter_start+0x434/0x10d0 drivers/media/dvb-core/dmxdev.c:769
 dvb_demux_do_ioctl+0x48b/0x540 drivers/media/dvb-core/dmxdev.c:1099
 dvb_usercopy+0x199/0x2e0 drivers/media/dvb-core/dvbdev.c:996
 dvb_demux_ioctl+0x29/0x40 drivers/media/dvb-core/dmxdev.c:1208
 __do_compat_sys_ioctl fs/ioctl.c:695 [inline]
 __se_compat_sys_ioctl fs/ioctl.c:638 [inline]
 __ia32_compat_sys_ioctl+0x5ea/0x950 fs/ioctl.c:638
 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:79 [inline]
 __do_fast_syscall_32+0x27a/0x6a0 arch/x86/entry/syscall_32.c:291
 do_fast_syscall_32+0x33/0x70 arch/x86/entry/syscall_32.c:316
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e
RIP: 0023:0xf706f0ec
Code: 90 85 d2 74 0a 89 ce 81 e6 ff 0f 00 00 89 32 85 c0 74 05 c1 e9 0c 89 08 31 c0 5e 5d c3 90 0f 1f 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 58 b8
RSP: 002b:00000000ffb07a2c EFLAGS: 00000206 ORIG_RAX: 0000000000000036
RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 0000000040146f2c
RDX: 0000000080000300 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 </TASK>
----------------
Code disassembly (best guess):
   0:	e8 7d 79 c9 fa       	call   0xfac97982
   5:	4c 89 f7             	mov    %r14,%rdi
   8:	4d 8b 6d 00          	mov    0x0(%r13),%r13
   c:	41 0f b6 04 2c       	movzbl (%r12,%rbp,1),%eax
  11:	84 c0                	test   %al,%al
  13:	48 8b 54 24 18       	mov    0x18(%rsp),%rdx
  18:	0f 85 97 07 00 00    	jne    0x7b5
  1e:	8b 0a                	mov    (%rdx),%ecx
  20:	48 8b 34 24          	mov    (%rsp),%rsi
  24:	4c 89 ea             	mov    %r13,%rdx
  27:	45 89 f8             	mov    %r15d,%r8d
* 2a:	67 48 0f b9 3a       	ud1    (%edx),%rdi <-- trapping instruction
  2f:	4c 8b 6c 24 08       	mov    0x8(%rsp),%r13
  34:	4c 89 ef             	mov    %r13,%rdi
  37:	48 c7 c6 80 2b b0 8f 	mov    $0xffffffff8fb02b80,%rsi
  3e:	e8                   	.byte 0xe8
  3f:	9f                   	lahf

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/09/18 17:39 upstream 50d05c7c76c9 8d7d05f1 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-386 WARNING in ttusb_start_feed/usb_submit_urb
2026/09/18 16:40 upstream 50d05c7c76c9 8d7d05f1 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-386 WARNING in ttusb_start_feed/usb_submit_urb
2026/09/18 15:30 upstream 50d05c7c76c9 8d7d05f1 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-386 WARNING in ttusb_start_feed/usb_submit_urb
* Struck through repros no longer work on HEAD.