From: syzbot <syzbot+7b70c4a6021fd49c4151@syzkaller.appspotmail.com>
To: gregkh@linuxfoundation.org, linux-kernel@vger.kernel.org,
linux-usb@vger.kernel.org, syzkaller-bugs@googlegroups.com
Subject: [syzbot] [usb?] WARNING in usb_ep_enable
Date: Fri, 31 Jul 2026 10:13:33 -0700 [thread overview]
Message-ID: <6a6cd7bd.1aa927e4.17d4bf.0004.GAE@google.com> (raw)
Hello,
syzbot found the following issue on:
HEAD commit: 11028ab62899 Merge tag 'probes-fixes-v7.2-rc5' of git://gi..
git tree: upstream
console+strace: https://syzkaller.appspot.com/x/log.txt?x=1673649e580000
kernel config: https://syzkaller.appspot.com/x/.config?x=cb17729fb04b1e3a
dashboard link: https://syzkaller.appspot.com/bug?extid=7b70c4a6021fd49c4151
compiler: Debian clang version 22.1.8 (++20260613092233+e80beda6e255-1~exp1~20260613092250.77), Debian LLD 22.1.8
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=13074aea580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=161271b9580000
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/bc967be819a3/disk-11028ab6.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/6e9f003c9cc8/vmlinux-11028ab6.xz
kernel image: https://storage.googleapis.com/syzbot-assets/5c292926486f/bzImage-11028ab6.xz
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+7b70c4a6021fd49c4151@syzkaller.appspotmail.com
------------[ 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#1: ktimers/1/29
Modules linked in:
CPU: 1 UID: 0 PID: 29 Comm: ktimers/1 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: 4a 17 02 fb 49 83 3f 00 48 c7 c0 60 b3 1f 8c 49 c7 c0 80 b3 1f 8c 4c 0f 44 c0 4c 89 f7 48 c7 c6 8b 42 b0 8d 44 89 ea 4c 89 e1 <67> 48 0f b9 3a bd ea ff ff ff 0f 1f 44 00 00 e8 40 a4 98 fa 65 8b
RSP: 0018:ffffc90000a3f6b8 EFLAGS: 00010282
RAX: ffffffff8c1fb360 RBX: ffff88802a08c120 RCX: ffffffff8c1fd1e0
RDX: 0000000000000081 RSI: ffffffff8db0428b RDI: ffffffff8fbc9d40
RBP: dffffc0000000000 R08: ffffffff8c1fb380 R09: 0000000000000100
R10: 0000000000000100 R11: 0000000000000003 R12: ffffffff8c1fd1e0
R13: 0000000000000081 R14: ffffffff8fbc9d40 R15: ffff88802a08c138
FS: 0000000000000000(0000) GS:ffff888125d41000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000563af0aa84a0 CR3: 00000000382cc000 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:2032 [inline]
__hrtimer_run_queues+0x3eb/0xaf0 kernel/time/hrtimer.c:2096
hrtimer_run_softirq+0x18f/0x260 kernel/time/hrtimer.c:2113
handle_softirqs+0x1d9/0x6c0 kernel/softirq.c:622
__do_softirq kernel/softirq.c:656 [inline]
run_ktimerd+0x69/0x100 kernel/softirq.c:1151
smpboot_thread_fn+0x57c/0xa80 kernel/smpboot.c:160
kthread+0x388/0x470 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: 4a 17 rex.WX (bad)
2: 02 fb add %bl,%bh
4: 49 83 3f 00 cmpq $0x0,(%r15)
8: 48 c7 c0 60 b3 1f 8c mov $0xffffffff8c1fb360,%rax
f: 49 c7 c0 80 b3 1f 8c mov $0xffffffff8c1fb380,%r8
16: 4c 0f 44 c0 cmove %rax,%r8
1a: 4c 89 f7 mov %r14,%rdi
1d: 48 c7 c6 8b 42 b0 8d mov $0xffffffff8db0428b,%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 40 a4 98 fa call 0xfa98a47e
3e: 65 gs
3f: 8b .byte 0x8b
---
This report is generated by a bot. It may contain errors.
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If the report is already addressed, let syzbot know by replying with:
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next reply other threads:[~2026-07-31 17:13 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-07-31 17:13 syzbot [this message]
2026-07-31 22:55 ` [syzbot] [usb?] WARNING in usb_ep_enable syzbot
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