WARNING in usb_ep_enable

Status: upstream: reported C repro on 2026/07/31 17:13
Subsystems: usb
Labels: prio:high
[Documentation on labels]
Reported-by: syzbot+7b70c4a6021fd49c4151@syzkaller.appspotmail.com
First crash: 58d, last: 40m
Cause bisection: introduced by (bisect log) :
commit 973a57891608a98e894db2887f278777f564de18
Author: Chris Wulff <crwulff@gmail.com>
Date: Thu Jul 25 01:04:20 2024 +0000

  usb: gadget: core: Check for unset descriptor

Crash: WARNING in usb_ep_enable (log)
Repro: C syz .config
  
▶ ▼ ✨ AI Jobs (1)
ID Workflow Result Correct Bug Created Started Finished Revision
ee053112 assessment-security DenialOfService: ❌ Exploitable: ❌ FilesystemTrigger: ❌ NetworkTrigger: ❌ PeripheralTrigger: ❌ RemoteTrigger: ❌ Unprivileged: ❌ UserNamespace: ❌ VMGuestTrigger: ✅ VMHostTrigger: ❌ ❓ WARNING in usb_ep_enable 2026/07/31 02:54 2026/07/31 02:54 2026/07/31 04:00 aaffb173
▶ ▼ Discussions (4)
Title Replies (including bot) Last reply
[syzbot] Monthly usb report (Sep 2026) 0 (1) 2026/09/04 12:33
[PATCH v2] usb: gadget: f_hid: reject zero report length 1 (1) 2026/08/02 18:12
[PATCH] usb: gadget: f_hid: reject zero report length 2 (2) 2026/08/02 06:47
[syzbot] [usb?] WARNING in usb_ep_enable 0 (3) 2026/08/01 20:52
▶ ▼ 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 128 1d09h 56d 0/3 upstream: reported C repro on 2026/07/31 20:18
android-6-12 WARNING in usb_ep_enable -1 syz, C 96 9h05m 58d 0/1 premoderation: reported C repro on 2026/07/30 13:40
linux-6.1 WARNING in usb_ep_enable -1 syz, C 207 4h39m 56d 0/3 upstream: reported C repro on 2026/08/01 09:05
linux-6.6 WARNING in usb_ep_enable origin:upstream -1 syz, C 132 2d06h 56d 0/2 upstream: reported C repro on 2026/07/31 21:09
▶ ▼ Last patch testing requests (1)
Created Duration User Patch Repo Result
2026/08/01 20:52 30m lurenjia534@outlook.com patch git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git 5d5fd841c34649f1b09220fe58e59dffd61c447d OK log

Sample crash report:
------------[ cut here ]------------
usb_ep_enable: ep129 (ep1in-bulk) has maxpacket 0
WARNING: drivers/usb/gadget/udc/core.c:125 at usb_ep_enable+0x148/0x480 drivers/usb/gadget/udc/core.c:124, CPU#0: ktimers/0/16
Modules linked in:
CPU: 0 UID: 0 PID: 16 Comm: ktimers/0 Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
RIP: 0010:usb_ep_enable+0x1bc/0x480 drivers/usb/gadget/udc/core.c:124
Code: ca 4c f9 fa 49 83 3f 00 48 c7 c0 40 b9 21 8c 49 c7 c0 60 b9 21 8c 4c 0f 44 c0 4c 89 f7 48 c7 c6 a7 f5 ae 8d 44 89 ea 4c 89 e1 <67> 48 0f b9 3a bd ea ff ff ff 0f 1f 44 00 00 e8 60 62 8d fa 65 8b
RSP: 0018:ffffc900001576b8 EFLAGS: 00010286
RAX: ffffffff8c21b940 RBX: ffff888029d44120 RCX: ffffffff8c21d7c0
RDX: 0000000000000081 RSI: ffffffff8daef5a7 RDI: ffffffff8fbef260
RBP: dffffc0000000000 R08: ffffffff8c21b960 R09: 0000000000000100
R10: 0000000000000100 R11: 0000000000000003 R12: ffffffff8c21d7c0
R13: 0000000000000081 R14: ffffffff8fbef260 R15: ffff888029d44138
FS:  0000000000000000(0000) GS:ffff888125bc4000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fac539855e0 CR3: 0000000042184000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 hidg_set_alt+0x12a/0xa50 drivers/usb/gadget/function/f_hid.c:1042
 set_config+0x749/0x1160 drivers/usb/gadget/composite.c:1018
 composite_setup+0x1de7/0x3480 drivers/usb/gadget/composite.c:1901
 configfs_composite_setup+0xbd/0x100 drivers/usb/gadget/configfs.c:1877
 dummy_timer+0x2f77/0x4d50 drivers/usb/gadget/udc/dummy_hcd.c:1951
 __run_hrtimer kernel/time/hrtimer.c:2074 [inline]
 __hrtimer_run_queues+0x3eb/0xaf0 kernel/time/hrtimer.c:2131
 hrtimer_run_softirq+0x1e1/0x2e0 kernel/time/hrtimer.c:2148
 handle_softirqs+0x1da/0x6d0 kernel/softirq.c:645
 __do_softirq kernel/softirq.c:679 [inline]
 run_ktimerd+0x6a/0x100 kernel/softirq.c:1174
 smpboot_thread_fn+0x565/0xa70 kernel/smpboot.c:160
 kthread+0x38b/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>
----------------
Code disassembly (best guess):
   0:	ca 4c f9             	lret   $0xf94c
   3:	fa                   	cli
   4:	49 83 3f 00          	cmpq   $0x0,(%r15)
   8:	48 c7 c0 40 b9 21 8c 	mov    $0xffffffff8c21b940,%rax
   f:	49 c7 c0 60 b9 21 8c 	mov    $0xffffffff8c21b960,%r8
  16:	4c 0f 44 c0          	cmove  %rax,%r8
  1a:	4c 89 f7             	mov    %r14,%rdi
  1d:	48 c7 c6 a7 f5 ae 8d 	mov    $0xffffffff8daef5a7,%rsi
  24:	44 89 ea             	mov    %r13d,%edx
  27:	4c 89 e1             	mov    %r12,%rcx
* 2a:	67 48 0f b9 3a       	ud1    (%edx),%rdi <-- trapping instruction
  2f:	bd ea ff ff ff       	mov    $0xffffffea,%ebp
  34:	0f 1f 44 00 00       	nopl   0x0(%rax,%rax,1)
  39:	e8 60 62 8d fa       	call   0xfa8d629e
  3e:	65                   	gs
  3f:	8b                   	.byte 0x8b

Crashes (1888):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/09/26 13:51 upstream 6812ce4e4379 a3c7249d .config strace log report syz / log C [disk image] [vmlinux] [kernel image] ci2-upstream-fs WARNING in usb_ep_enable
2026/09/17 16:04 upstream 238650ef6c7c 95928915 .config strace log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING in usb_ep_enable
2026/08/14 18:29 upstream 2f1baf1fc892 6f9b3e89 .config strace log report syz / log C [disk image] [vmlinux] [kernel image] ci2-upstream-fs WARNING in usb_ep_enable
2026/08/13 15:33 upstream 3d6d817622b0 359b2492 .config strace log report syz / log C [disk image] [vmlinux] [kernel image] ci2-upstream-fs WARNING in usb_ep_enable
2026/08/13 10:24 upstream 3d6d817622b0 359b2492 .config strace log report syz / log C [disk image] [vmlinux] [kernel image] ci2-upstream-fs WARNING in usb_ep_enable
2026/08/12 11:32 upstream f5bbbfec59b4 f8d35649 .config strace log report syz / log C [disk image] [vmlinux] [kernel image] ci2-upstream-fs WARNING in usb_ep_enable
2026/08/11 10:27 upstream d58772d8520c 508909ea .config strace log report syz / log C [disk image] [vmlinux] [kernel image] ci2-upstream-fs WARNING in usb_ep_enable
2026/08/10 15:24 upstream db2ddb871435 5d63f80b .config strace log report syz / log C [disk image] [vmlinux] [kernel image] ci2-upstream-fs WARNING in usb_ep_enable
2026/08/10 01:58 upstream b9b3e33b70b7 5d63f80b .config strace log report syz / log C [disk image] [vmlinux] [kernel image] ci2-upstream-fs WARNING in usb_ep_enable
2026/07/30 17:05 upstream 11028ab62899 2377cd3d .config strace log report syz / log C [disk image] [vmlinux] [kernel image] ci2-upstream-fs WARNING in usb_ep_enable
2026/07/30 15:18 upstream 11028ab62899 2377cd3d .config strace log report syz / log C [disk image] [vmlinux] [kernel image] ci2-upstream-fs WARNING in usb_ep_enable
2026/09/26 14:02 upstream f14572c203d5 a3c7249d .config console log report syz / log C [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in usb_ep_enable
2026/08/14 16:37 upstream 2f1baf1fc892 2cf1fbb7 .config console log report syz / log C [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in usb_ep_enable
2026/08/13 00:44 upstream 3d6d817622b0 359b2492 .config console log report syz / log C [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in usb_ep_enable
2026/08/12 15:59 upstream f5bbbfec59b4 ee03bfea .config console log report syz / log C [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in usb_ep_enable
2026/08/10 10:56 upstream db2ddb871435 558388e4 .config console log report syz / log C [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in usb_ep_enable
2026/08/09 23:16 upstream b643e495ae92 5d63f80b .config console log report syz / log C [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in usb_ep_enable
2026/08/09 14:07 upstream 06cf61899d64 5d63f80b .config console log report syz / log C [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in usb_ep_enable
2026/09/05 10:58 linux-next 9d80aa4617b3 4f7b22a0 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING in usb_ep_enable
2026/08/31 11:01 linux-next e30626823a40 2f52988a .config strace log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING in usb_ep_enable
2026/08/31 04:25 linux-next e30626823a40 2f52988a .config strace log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING in usb_ep_enable
2026/08/12 15:30 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 21d6ac051080 7ae4acc7 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in usb_ep_enable
2026/09/26 13:41 upstream 6812ce4e4379 a3c7249d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING in usb_ep_enable
2026/09/26 13:12 upstream 6812ce4e4379 a3c7249d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING in usb_ep_enable
2026/09/26 04:54 upstream aa98230e410f f281d9d2 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root WARNING in usb_ep_enable
2026/09/25 23:56 upstream aa98230e410f f281d9d2 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in usb_ep_enable
2026/09/25 19:41 upstream 165768bb7026 f281d9d2 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root WARNING in usb_ep_enable
2026/09/25 16:55 upstream 165768bb7026 f281d9d2 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in usb_ep_enable
2026/09/25 01:54 upstream f49a343b305c 3c3cdf19 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-badwrites-root WARNING in usb_ep_enable
2026/09/24 10:18 upstream 62f4c998b297 3c3cdf19 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in usb_ep_enable
2026/09/23 22:48 upstream fe2ec83746e5 0a1606bc .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root WARNING in usb_ep_enable
2026/09/23 21:07 upstream fe2ec83746e5 0a1606bc .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in usb_ep_enable
2026/09/23 17:39 upstream fe2ec83746e5 abce1216 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root WARNING in usb_ep_enable
2026/09/23 16:25 upstream fe2ec83746e5 abce1216 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root WARNING in usb_ep_enable
2026/09/22 18:53 upstream c4e9f74da438 e12281bd .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs WARNING in usb_ep_enable
2026/09/26 12:02 upstream f14572c203d5 a3c7249d .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in usb_ep_enable
2026/09/26 10:49 upstream f14572c203d5 a3c7249d .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in usb_ep_enable
2026/09/26 08:34 upstream f14572c203d5 a3c7249d .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in usb_ep_enable
2026/09/26 08:04 upstream f14572c203d5 a3c7249d .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in usb_ep_enable
2026/09/26 00:59 upstream f14572c203d5 f281d9d2 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in usb_ep_enable
2026/09/25 18:22 upstream 165768bb7026 f281d9d2 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in usb_ep_enable
2026/09/25 07:12 upstream 5fc5768c7ca9 27d05fb3 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in usb_ep_enable
2026/09/25 05:01 upstream 5fc5768c7ca9 27d05fb3 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in usb_ep_enable
2026/09/25 03:47 upstream 5fc5768c7ca9 27d05fb3 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in usb_ep_enable
2026/09/24 16:59 upstream 62f4c998b297 3c3cdf19 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in usb_ep_enable
2026/09/24 15:15 upstream 62f4c998b297 3c3cdf19 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in usb_ep_enable
2026/09/24 14:14 upstream 62f4c998b297 3c3cdf19 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in usb_ep_enable
2026/09/24 12:40 upstream 62f4c998b297 3c3cdf19 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in usb_ep_enable
2026/09/24 11:42 upstream 62f4c998b297 3c3cdf19 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in usb_ep_enable
2026/09/24 09:02 upstream 62f4c998b297 3c3cdf19 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in usb_ep_enable
2026/09/24 07:49 upstream 62f4c998b297 3c3cdf19 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in usb_ep_enable
2026/09/24 06:24 upstream 62f4c998b297 3c3cdf19 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in usb_ep_enable
2026/09/24 05:10 upstream 62f4c998b297 3c3cdf19 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in usb_ep_enable
2026/09/24 02:07 upstream 62f4c998b297 0a1606bc .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in usb_ep_enable
2026/09/26 16:19 upstream 6812ce4e4379 a3c7249d .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 WARNING in usb_ep_enable
2026/09/24 21:26 upstream 5fc5768c7ca9 27d05fb3 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 WARNING in usb_ep_enable
2026/09/24 03:07 upstream fe2ec83746e5 0a1606bc .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 WARNING in usb_ep_enable
2026/09/26 09:39 linux-next f5f84daefcd9 a3c7249d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING in usb_ep_enable
2026/09/25 09:56 linux-next 4c253ac4b29b f281d9d2 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root WARNING in usb_ep_enable
2026/09/25 00:39 linux-next 4c253ac4b29b 3c3cdf19 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING in usb_ep_enable
2026/09/24 06:37 linux-next 3d7783543c26 0a1606bc .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root WARNING in usb_ep_enable
2026/09/24 04:24 linux-next 9d80aa4617b3 0a1606bc .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING in usb_ep_enable
2026/09/24 00:16 linux-next a8c591ed6b67 0a1606bc .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root WARNING in usb_ep_enable
2026/09/23 21:39 linux-next a8c591ed6b67 0a1606bc .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root WARNING in usb_ep_enable
2026/09/23 15:01 linux-next a8c591ed6b67 abce1216 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root WARNING in usb_ep_enable
2026/09/23 14:53 linux-next a8c591ed6b67 abce1216 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root WARNING in usb_ep_enable
2026/09/23 14:47 linux-next a8c591ed6b67 abce1216 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root WARNING in usb_ep_enable
2026/09/23 14:40 linux-next a8c591ed6b67 abce1216 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root WARNING in usb_ep_enable
2026/09/23 14:31 linux-next a8c591ed6b67 abce1216 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root WARNING in usb_ep_enable
2026/09/23 14:21 linux-next a8c591ed6b67 abce1216 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root WARNING in usb_ep_enable
2026/09/23 13:48 linux-next a8c591ed6b67 abce1216 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root WARNING in usb_ep_enable
2026/09/23 13:41 linux-next a8c591ed6b67 abce1216 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root WARNING in usb_ep_enable
2026/09/23 13:30 linux-next a8c591ed6b67 abce1216 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root WARNING in usb_ep_enable
2026/09/24 04:13 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 7dc79bb50ab6 0a1606bc .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in usb_ep_enable
2026/09/25 06:13 https://kernel.googlesource.com/pub/scm/linux/kernel/git/torvalds/linux master 73ae59e97596 27d05fb3 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu2-arm64-mte WARNING in usb_ep_enable
2026/09/24 19:14 https://kernel.googlesource.com/pub/scm/linux/kernel/git/torvalds/linux master 73ae59e97596 3c3cdf19 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu2-arm64 WARNING in usb_ep_enable
2026/09/24 03:09 https://kernel.googlesource.com/pub/scm/linux/kernel/git/torvalds/linux master 73ae59e97596 0a1606bc .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu2-arm64-mte WARNING in usb_ep_enable
2026/09/21 10:08 https://kernel.googlesource.com/pub/scm/linux/kernel/git/torvalds/linux master 73ae59e97596 853b104b .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu2-arm64-compat WARNING in usb_ep_enable
2026/09/21 02:36 git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux.git for-next e11160948333 853b104b .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu2-riscv64 WARNING in usb_ep_enable
* Struck through repros no longer work on HEAD.