From: syzbot <syzbot+7e1e5911f9eac50bedc7@syzkaller.appspotmail.com>
To: gregkh@linuxfoundation.org, linux-kernel@vger.kernel.org,
linux-usb@vger.kernel.org, syzkaller-bugs@googlegroups.com
Subject: [syzbot] [usb?] general protection fault in usbtest_probe
Date: Tue, 28 Jul 2026 17:19:30 -0700 [thread overview]
Message-ID: <6a694712.6bd615f2.c0aa.0003.GAE@google.com> (raw)
Hello,
syzbot found the following issue on:
HEAD commit: 3b5f4b83c4ab Merge tag 'for-7.2-rc5-tag' of git://git.kern..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=12eee7b1580000
kernel config: https://syzkaller.appspot.com/x/.config?x=145fa60d73086782
dashboard link: https://syzkaller.appspot.com/bug?extid=7e1e5911f9eac50bedc7
compiler: gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=12f41449580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1797249e580000
Downloadable assets:
disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/d900f083ada3/non_bootable_disk-3b5f4b83.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/ed6d6b480fd7/vmlinux-3b5f4b83.xz
kernel image: https://storage.googleapis.com/syzbot-assets/d5a591a74024/bzImage-3b5f4b83.xz
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+7e1e5911f9eac50bedc7@syzkaller.appspotmail.com
usb 5-1: New USB device found, idVendor=0547, idProduct=2235, bcdDevice= 0.00
usb 5-1: New USB device strings: Mfr=1, Product=2, SerialNumber=3
usb 5-1: Product: syz
usb 5-1: Manufacturer: syz
usb 5-1: SerialNumber: syz
Oops: general protection fault, probably for non-canonical address 0xdffffc0000000001: 0000 [#1] SMP KASAN NOPTI
KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f]
CPU: 1 UID: 0 PID: 29 Comm: kworker/1:0 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
Workqueue: usb_hub_wq hub_event
RIP: 0010:usbtest_probe+0x3b9/0x1280 drivers/usb/misc/usbtest.c:2822
Code: e9 46 fa 45 85 ff 79 5e e8 34 ef 46 fa 48 8b 84 24 80 00 00 00 48 8d 58 0a 48 b8 00 00 00 00 00 fc ff df 48 89 da 48 c1 ea 03 <0f> b6 04 02 48 89 da 83 e2 07 38 d0 7f 08 84 c0 0f 85 58 0d 00 00
RSP: 0018:ffffc90000686fc8 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: 000000000000000a RCX: ffffffff87c37102
RDX: 0000000000000001 RSI: ffffffff87c3710c RDI: ffff88801f69a540
RBP: ffff88802bf65910 R08: 0000000000000005 R09: 0000000000000000
R10: 00000000ffffffff R11: 000000000000758b R12: ffff88816db048b0
R13: ffff88803724fed0 R14: ffff88803724fe00 R15: 00000000ffffffff
FS: 0000000000000000(0000) GS:ffff8880d5edc000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f87747eb580 CR3: 000000002ad51000 CR4: 0000000000352ef0
Call Trace:
<TASK>
usb_probe_interface+0x303/0x8f0 drivers/usb/core/driver.c:396
call_driver_probe drivers/base/dd.c:628 [inline]
really_probe+0x241/0xa60 drivers/base/dd.c:706
__driver_probe_device+0x20e/0x450 drivers/base/dd.c:868
driver_probe_device+0x4a/0x140 drivers/base/dd.c:898
__device_attach_driver+0x1df/0x320 drivers/base/dd.c:1026
bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:500
__device_attach+0x1e4/0x4d0 drivers/base/dd.c:1098
device_initial_probe+0xaf/0xd0 drivers/base/dd.c:1153
bus_probe_device+0x64/0x160 drivers/base/bus.c:620
device_add+0x121d/0x1970 drivers/base/core.c:3772
usb_set_configuration+0xd97/0x1c60 drivers/usb/core/message.c:2268
usb_generic_driver_probe+0xa1/0xe0 drivers/usb/core/generic.c:250
usb_probe_device+0xef/0x400 drivers/usb/core/driver.c:291
call_driver_probe drivers/base/dd.c:628 [inline]
really_probe+0x241/0xa60 drivers/base/dd.c:706
__driver_probe_device+0x20e/0x450 drivers/base/dd.c:868
driver_probe_device+0x4a/0x140 drivers/base/dd.c:898
__device_attach_driver+0x1df/0x320 drivers/base/dd.c:1026
bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:500
__device_attach+0x1e4/0x4d0 drivers/base/dd.c:1098
device_initial_probe+0xaf/0xd0 drivers/base/dd.c:1153
bus_probe_device+0x64/0x160 drivers/base/bus.c:620
device_add+0x121d/0x1970 drivers/base/core.c:3772
usb_new_device.cold+0x685/0x115c drivers/usb/core/hub.c:2695
hub_port_connect drivers/usb/core/hub.c:5567 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5707 [inline]
port_event drivers/usb/core/hub.c:5871 [inline]
hub_event+0x30a3/0x4a60 drivers/usb/core/hub.c:5953
process_one_work+0xa23/0x1940 kernel/workqueue.c:3322
process_scheduled_works kernel/workqueue.c:3405 [inline]
worker_thread+0x5ef/0xe50 kernel/workqueue.c:3486
kthread+0x370/0x450 kernel/kthread.c:436
ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:usbtest_probe+0x3b9/0x1280 drivers/usb/misc/usbtest.c:2822
Code: e9 46 fa 45 85 ff 79 5e e8 34 ef 46 fa 48 8b 84 24 80 00 00 00 48 8d 58 0a 48 b8 00 00 00 00 00 fc ff df 48 89 da 48 c1 ea 03 <0f> b6 04 02 48 89 da 83 e2 07 38 d0 7f 08 84 c0 0f 85 58 0d 00 00
RSP: 0018:ffffc90000686fc8 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: 000000000000000a RCX: ffffffff87c37102
RDX: 0000000000000001 RSI: ffffffff87c3710c RDI: ffff88801f69a540
RBP: ffff88802bf65910 R08: 0000000000000005 R09: 0000000000000000
R10: 00000000ffffffff R11: 000000000000758b R12: ffff88816db048b0
R13: ffff88803724fed0 R14: ffff88803724fe00 R15: 00000000ffffffff
FS: 0000000000000000(0000) GS:ffff8880d5edc000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f87747eb580 CR3: 000000002a8fe000 CR4: 0000000000352ef0
----------------
Code disassembly (best guess), 1 bytes skipped:
0: 46 fa rex.RX cli
2: 45 85 ff test %r15d,%r15d
5: 79 5e jns 0x65
7: e8 34 ef 46 fa call 0xfa46ef40
c: 48 8b 84 24 80 00 00 mov 0x80(%rsp),%rax
13: 00
14: 48 8d 58 0a lea 0xa(%rax),%rbx
18: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax
1f: fc ff df
22: 48 89 da mov %rbx,%rdx
25: 48 c1 ea 03 shr $0x3,%rdx
* 29: 0f b6 04 02 movzbl (%rdx,%rax,1),%eax <-- trapping instruction
2d: 48 89 da mov %rbx,%rdx
30: 83 e2 07 and $0x7,%edx
33: 38 d0 cmp %dl,%al
35: 7f 08 jg 0x3f
37: 84 c0 test %al,%al
39: 0f 85 58 0d 00 00 jne 0xd97
---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzkaller@googlegroups.com.
syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
If the report is already addressed, let syzbot know by replying with:
#syz fix: exact-commit-title
If you want syzbot to run the reproducer, reply with:
#syz test: git://repo/address.git branch-or-commit-hash
If you attach or paste a git patch, syzbot will apply it before testing.
If you want to overwrite report's subsystems, reply with:
#syz set subsystems: new-subsystem
(See the list of subsystem names on the web dashboard)
If the report is a duplicate of another one, reply with:
#syz dup: exact-subject-of-another-report
If you want to undo deduplication, reply with:
#syz undup
reply other threads:[~2026-07-29 0:19 UTC|newest]
Thread overview: [no followups] expand[flat|nested] mbox.gz Atom feed
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=6a694712.6bd615f2.c0aa.0003.GAE@google.com \
--to=syzbot+7e1e5911f9eac50bedc7@syzkaller.appspotmail.com \
--cc=gregkh@linuxfoundation.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-usb@vger.kernel.org \
--cc=syzkaller-bugs@googlegroups.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox