WARNING in usb_ep_enable

Status: upstream: reported C repro on 2026/07/31 21:09
Bug presence: origin:upstream
[Documentation on labels]
Reported-by: syzbot+d851455dbf571fe8e225@syzkaller.appspotmail.com
First crash: 101d, last: 5h38m
▶ ▼ Bug presence (1)
Date Name Commit Repro Result
2026/09/19 upstream (ToT) 40288c9206c1 C [report] WARNING in usb_ep_enable
▶ ▼ Similar bugs (4)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-5.15 WARNING in usb_ep_enable origin:upstream -1 syz, C 222 2d23h 101d 0/3 upstream: reported C repro on 2026/07/31 20:18
android-6-12 WARNING in usb_ep_enable origin:upstream -1 syz, C 210 2d08h 102d 0/1 premoderation: reported C repro on 2026/07/30 13:40
linux-6.1 WARNING in usb_ep_enable -1 syz, C 476 23h56m 100d 0/3 upstream: reported C repro on 2026/08/01 09:05
upstream WARNING in usb_ep_enable prio:high usb -1 syz, C done 3849 now 101d 0/29 upstream: reported C repro on 2026/07/31 17:13

Sample crash report:
------------[ cut here ]------------
usb_ep_enable: ep129 (ep1in-bulk) has maxpacket 0
WARNING: CPU: 0 PID: 5809 at drivers/usb/gadget/udc/core.c:125 usb_ep_enable+0x263/0x440 drivers/usb/gadget/udc/core.c:124
Modules linked in:
CPU: 0 PID: 5809 Comm: kworker/0:4 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Workqueue: usb_hub_wq hub_event
RIP: 0010:usb_ep_enable+0x263/0x440 drivers/usb/gadget/udc/core.c:124
Code: 49 8b 0e 48 c7 c0 00 ed 7a 8b 49 c7 c0 20 ed 7a 8b 4c 0f 44 c0 48 c7 c7 c0 ec 7a 8b 48 c7 c6 51 bf a6 8c 89 ea e8 7d fe 95 fa <0f> 0b e9 e1 fe ff ff e8 61 31 cc fa 49 bc 00 00 00 00 00 fc ff df
RSP: 0018:ffffc90000007790 EFLAGS: 00010046
RAX: f0055689ce2c9c00 RBX: ffff8881427740e0 RCX: ffff888066915a00
RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000002
RBP: 0000000000000081 R08: ffff8880b8e28c53 R09: 1ffff110171c518a
R10: dffffc0000000000 R11: ffffed10171c518b R12: dffffc0000000000
R13: ffff88814277410d R14: ffff8881427740e8 R15: ffff88807447373a
FS:  0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffc92176cc8 CR3: 000000002cf81000 CR4: 00000000003506f0
Call Trace:
 <IRQ>
 hidg_set_alt+0x12a/0xa10 drivers/usb/gadget/function/f_hid.c:826
 set_config+0x735/0xff0 drivers/usb/gadget/composite.c:1018
 composite_setup+0x1df4/0x33a0 drivers/usb/gadget/composite.c:1925
 configfs_composite_setup+0xc7/0x100 drivers/usb/gadget/configfs.c:1875
 dummy_timer+0x1324/0x34e0 drivers/usb/gadget/udc/dummy_hcd.c:1949
 __run_hrtimer kernel/time/hrtimer.c:1754 [inline]
 __hrtimer_run_queues+0x525/0xc10 kernel/time/hrtimer.c:1818
 hrtimer_run_softirq+0x177/0x290 kernel/time/hrtimer.c:1835
 handle_softirqs+0x27d/0x820 kernel/softirq.c:578
 __do_softirq kernel/softirq.c:612 [inline]
 invoke_softirq kernel/softirq.c:452 [inline]
 __irq_exit_rcu+0xd3/0x190 kernel/softirq.c:661
 irq_exit_rcu+0x9/0x20 kernel/softirq.c:673
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline]
 sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1088
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0xc0/0x120 kernel/locking/spinlock.c:194
Code: c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f7 44 24 20 00 02 00 00 41 c6 04 07 f8 75 4b f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 <e8> 6b 28 c4 f6 65 8b 05 cc f6 6a 75 85 c0 74 3c 48 c7 04 24 0e 36
RSP: 0018:ffffc9000462efe0 EFLAGS: 00000206
RAX: dffffc0000000004 RBX: 0000000000000a06 RCX: f0055689ce2c9c00
RDX: dffffc0000000000 RSI: ffffffff8acacbe0 RDI: 0000000000000001
RBP: ffffc9000462f070 R08: ffffffff911ed56f R09: 1ffffffff223daad
R10: dffffc0000000000 R11: fffffbfff223daae R12: dffffc0000000000
R13: dffffc0000000000 R14: ffff888142774000 R15: 1ffff920008c5dfc
 spin_unlock_irqrestore include/linux/spinlock.h:406 [inline]
 dummy_urb_enqueue+0x587/0x780 drivers/usb/gadget/udc/dummy_hcd.c:1336
 usb_hcd_submit_urb+0x318/0x1aa0 drivers/usb/core/hcd.c:1533
 usb_start_wait_urb+0x140/0x580 drivers/usb/core/message.c:62
 usb_internal_control_msg drivers/usb/core/message.c:117 [inline]
 usb_control_msg+0x235/0x3e0 drivers/usb/core/message.c:167
 usb_control_msg_send drivers/usb/core/message.c:226 [inline]
 usb_set_configuration+0x12a8/0x2150 drivers/usb/core/message.c:2206
 usb_generic_driver_probe+0x8d/0x150 drivers/usb/core/generic.c:238
 usb_probe_device+0x12a/0x260 drivers/usb/core/driver.c:293
 call_driver_probe drivers/base/dd.c:-1 [inline]
 really_probe+0x247/0xae0 drivers/base/dd.c:717
 __driver_probe_device+0x1f5/0x390 drivers/base/dd.c:879
 driver_probe_device+0x4f/0x420 drivers/base/dd.c:909
 __device_attach_driver+0x2ca/0x510 drivers/base/dd.c:1037
 bus_for_each_drv+0x252/0x2e0 drivers/base/bus.c:459
 __device_attach+0x2c1/0x420 drivers/base/dd.c:1109
 bus_probe_device+0x180/0x260 drivers/base/bus.c:580
 device_add+0x87c/0xc40 drivers/base/core.c:3700
 usb_new_device+0x995/0x1550 drivers/usb/core/hub.c:2660
 hub_port_connect drivers/usb/core/hub.c:5529 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5669 [inline]
 port_event drivers/usb/core/hub.c:5833 [inline]
 hub_event+0x29d5/0x4a80 drivers/usb/core/hub.c:5915
 process_one_work kernel/workqueue.c:2657 [inline]
 process_scheduled_works+0xa60/0x1600 kernel/workqueue.c:2734
 worker_thread+0xa5e/0xfe0 kernel/workqueue.c:2815
 kthread+0x2fa/0x390 kernel/kthread.c:388
 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
 </TASK>
----------------
Code disassembly (best guess):
   0:	c7 44 24 20 00 00 00 	movl   $0x0,0x20(%rsp)
   7:	00
   8:	9c                   	pushf
   9:	8f 44 24 20          	pop    0x20(%rsp)
   d:	f7 44 24 20 00 02 00 	testl  $0x200,0x20(%rsp)
  14:	00
  15:	41 c6 04 07 f8       	movb   $0xf8,(%r15,%rax,1)
  1a:	75 4b                	jne    0x67
  1c:	f7 c3 00 02 00 00    	test   $0x200,%ebx
  22:	74 01                	je     0x25
  24:	fb                   	sti
  25:	bf 01 00 00 00       	mov    $0x1,%edi
* 2a:	e8 6b 28 c4 f6       	call   0xf6c4289a <-- trapping instruction
  2f:	65 8b 05 cc f6 6a 75 	mov    %gs:0x756af6cc(%rip),%eax        # 0x756af702
  36:	85 c0                	test   %eax,%eax
  38:	74 3c                	je     0x76
  3a:	48                   	rex.W
  3b:	c7                   	.byte 0xc7
  3c:	04 24                	add    $0x24,%al
  3e:	0e                   	(bad)
  3f:	36                   	ss

Crashes (233):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/08/11 11:16 linux-6.6.y d27334b2888c 508909ea .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in usb_ep_enable
2026/08/01 19:05 linux-6.6.y a1153c0deb44 e611ffe1 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in usb_ep_enable
2026/11/09 18:33 linux-6.6.y 5139929c698c 5cecaf1f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in usb_ep_enable
2026/11/08 11:13 linux-6.6.y 5139929c698c 5cecaf1f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in usb_ep_enable
2026/11/08 11:11 linux-6.6.y 5139929c698c 5cecaf1f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in usb_ep_enable
2026/11/06 01:54 linux-6.6.y b5a1dc3ad482 5cecaf1f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in usb_ep_enable
2026/11/05 11:57 linux-6.6.y b5a1dc3ad482 2ee8459f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in usb_ep_enable
2026/11/04 21:29 linux-6.6.y b5a1dc3ad482 73438ed0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in usb_ep_enable
2026/11/04 06:43 linux-6.6.y b5a1dc3ad482 5af5b6c6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in usb_ep_enable
2026/11/03 22:32 linux-6.6.y b5a1dc3ad482 e2d35131 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in usb_ep_enable
2026/11/03 20:27 linux-6.6.y b5a1dc3ad482 e2d35131 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in usb_ep_enable
2026/11/03 16:32 linux-6.6.y b5a1dc3ad482 e2d35131 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in usb_ep_enable
2026/11/02 18:22 linux-6.6.y b5a1dc3ad482 6969b601 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in usb_ep_enable
2026/11/02 00:45 linux-6.6.y b5a1dc3ad482 25a0ae84 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in usb_ep_enable
2026/11/02 00:02 linux-6.6.y b5a1dc3ad482 25a0ae84 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in usb_ep_enable
2026/10/30 22:14 linux-6.6.y b5a1dc3ad482 0ec395f8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in usb_ep_enable
2026/10/29 01:40 linux-6.6.y 0aebf2870d53 858db2ec .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in usb_ep_enable
2026/10/28 18:58 linux-6.6.y 0aebf2870d53 858db2ec .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in usb_ep_enable
2026/10/27 10:04 linux-6.6.y 0aebf2870d53 168cb7a2 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in usb_ep_enable
2026/10/23 11:24 linux-6.6.y 0aebf2870d53 d566bfda .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in usb_ep_enable
2026/10/22 18:19 linux-6.6.y 0aebf2870d53 b55fad29 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in usb_ep_enable
2026/10/20 10:13 linux-6.6.y cecd39af8a1a 72cdc28d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in usb_ep_enable
2026/10/10 00:55 linux-6.6.y a91a6aa9253c 4f92358f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in usb_ep_enable
2026/10/07 20:07 linux-6.6.y a91a6aa9253c 6520ecdb .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in usb_ep_enable
2026/10/06 13:32 linux-6.6.y a91a6aa9253c f7710056 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in usb_ep_enable
2026/10/03 19:45 linux-6.6.y a91a6aa9253c 57bbd979 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in usb_ep_enable
2026/10/03 17:52 linux-6.6.y a91a6aa9253c 57bbd979 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in usb_ep_enable
2026/10/03 04:57 linux-6.6.y 79643295eba1 57bbd979 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in usb_ep_enable
2026/10/03 03:51 linux-6.6.y 79643295eba1 57bbd979 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in usb_ep_enable
2026/10/03 03:51 linux-6.6.y 79643295eba1 57bbd979 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in usb_ep_enable
2026/10/02 13:15 linux-6.6.y 79643295eba1 6d32eb1f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in usb_ep_enable
2026/09/30 16:30 linux-6.6.y 79643295eba1 7808aef4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in usb_ep_enable
2026/09/30 13:40 linux-6.6.y 79643295eba1 7808aef4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in usb_ep_enable
2026/09/30 13:37 linux-6.6.y 79643295eba1 7808aef4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in usb_ep_enable
2026/09/29 11:53 linux-6.6.y 79643295eba1 7bf4ea23 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in usb_ep_enable
2026/09/28 07:42 linux-6.6.y 79643295eba1 a3c7249d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in usb_ep_enable
2026/09/27 18:30 linux-6.6.y 79643295eba1 a3c7249d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in usb_ep_enable
2026/09/24 10:59 linux-6.6.y 79643295eba1 0281b448 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in usb_ep_enable
2026/09/24 09:24 linux-6.6.y 79643295eba1 0281b448 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in usb_ep_enable
2026/09/24 05:57 linux-6.6.y 79643295eba1 0281b448 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in usb_ep_enable
2026/09/24 05:55 linux-6.6.y 79643295eba1 0281b448 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in usb_ep_enable
2026/09/23 17:50 linux-6.6.y 79643295eba1 abce1216 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in usb_ep_enable
2026/09/23 07:55 linux-6.6.y 79643295eba1 5207b90e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in usb_ep_enable
2026/09/23 04:09 linux-6.6.y 79643295eba1 5207b90e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in usb_ep_enable
2026/09/23 02:47 linux-6.6.y 79643295eba1 5207b90e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in usb_ep_enable
2026/07/31 21:08 linux-6.6.y a1153c0deb44 7664cf44 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in usb_ep_enable
* Struck through repros no longer work on HEAD.