From: syzbot <syzbot+ac9880be0b0b1a5f54d6@syzkaller.appspotmail.com>
To: linux-kernel@vger.kernel.org, linux-media@vger.kernel.org,
linux-usb@vger.kernel.org, mchehab@kernel.org,
syzkaller-bugs@googlegroups.com
Subject: [syzbot] [media?] [usb?] WARNING in ttusb_dec_send_command
Date: Fri, 31 Jul 2026 17:45:23 -0700 [thread overview]
Message-ID: <6a6d41a3.f794c993.27aeb.000e.GAE@google.com> (raw)
Hello,
syzbot found the following issue on:
HEAD commit: 5d5fd841c346 Merge 7.2-rc5 into usb-next
git tree: https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing
console output: https://syzkaller.appspot.com/x/log.txt?x=14114e32580000
kernel config: https://syzkaller.appspot.com/x/.config?x=6ec4d592e55f7960
dashboard link: https://syzkaller.appspot.com/bug?extid=ac9880be0b0b1a5f54d6
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=127da5b9580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=16c6f8c6580000
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/2ed536ae4daf/disk-5d5fd841.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/ab40098ccbf1/vmlinux-5d5fd841.xz
kernel image: https://storage.googleapis.com/syzbot-assets/66d5c395f47c/bzImage-5d5fd841.xz
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+ac9880be0b0b1a5f54d6@syzkaller.appspotmail.com
usb 4-1: config 1 interface 0 altsetting 0 has 2 endpoint descriptors, different from the interface descriptor's value: 5
usb 4-1: New USB device found, idVendor=0b48, idProduct=1008, bcdDevice= 1.00
usb 4-1: New USB device strings: Mfr=0, Product=0, SerialNumber=0
------------[ cut here ]------------
memcpy: detected buffer overflow: 75 byte read of buffer size 60
WARNING: lib/string_helpers.c:1036 at __fortify_report+0x8d/0xd0 lib/string_helpers.c:1036, CPU#0: kworker/0:1/11
Modules linked in:
CPU: 0 UID: 0 PID: 11 Comm: kworker/0:1 Not tainted syzkaller #0 PREEMPT(lazy)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Workqueue: usb_hub_wq hub_event
RIP: 0010:__fortify_report+0x99/0xd0 lib/string_helpers.c:1036
Code: ad 31 dc fe 45 84 f6 48 c7 c0 20 ec b0 87 48 0f 44 e8 e8 8a 37 dc fe 48 8d 3d 93 b9 20 08 4d 89 e8 48 89 e9 4c 89 e2 48 89 de <67> 48 0f b9 3a 5b 5d 41 5c 41 5d 41 5e e9 85 3a a7 04 48 89 de 48
RSP: 0018:ffffc900000bece8 EFLAGS: 00010293
RAX: 0000000000000000 RBX: ffffffff87b0f7c0 RCX: ffffffff87b0ec20
RDX: 000000000000004b RSI: ffffffff87b0f7c0 RDI: ffffffff8af88650
RBP: ffffffff87b0ec20 R08: 000000000000003c R09: 0000000000000000
R10: 0000000000000000 R11: ffffffff81595b4a R12: 000000000000004b
R13: 000000000000003c R14: 0000000000000000 R15: 1ffff92000017dac
FS: 0000000000000000(0000) GS:ffff888268636000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055d73a1cbc10 CR3: 0000000118014000 CR4: 00000000003506f0
Call Trace:
<TASK>
__fortify_panic+0x23/0x26 lib/string_helpers.c:1043
fortify_memcpy_chk include/linux/fortify-string.h:549 [inline]
ttusb_dec_send_command.cold+0x75/0xf8 drivers/media/usb/ttusb-dec/ttusb_dec.c:372
ttusb_dec_get_stb_state drivers/media/usb/ttusb-dec/ttusb_dec.c:392 [inline]
ttusb_dec_init_stb drivers/media/usb/ttusb-dec/ttusb_dec.c:1413 [inline]
ttusb_dec_probe+0x8b4/0x2110 drivers/media/usb/ttusb-dec/ttusb_dec.c:1671
usb_probe_interface+0x386/0x9b0 drivers/usb/core/driver.c:399
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:293
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:2700
hub_port_connect drivers/usb/core/hub.c:5572 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5712 [inline]
port_event drivers/usb/core/hub.c:5876 [inline]
hub_event+0x314d/0x4af0 drivers/usb/core/hub.c:5958
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+0x69a/0xc80 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: ad lods %ds:(%rsi),%eax
1: 31 dc xor %ebx,%esp
3: fe 45 84 incb -0x7c(%rbp)
6: f6 48 c7 c0 testb $0xc0,-0x39(%rax)
a: 20 ec and %ch,%ah
c: b0 87 mov $0x87,%al
e: 48 0f 44 e8 cmove %rax,%rbp
12: e8 8a 37 dc fe call 0xfedc37a1
17: 48 8d 3d 93 b9 20 08 lea 0x820b993(%rip),%rdi # 0x820b9b1
1e: 4d 89 e8 mov %r13,%r8
21: 48 89 e9 mov %rbp,%rcx
24: 4c 89 e2 mov %r12,%rdx
27: 48 89 de mov %rbx,%rsi
* 2a: 67 48 0f b9 3a ud1 (%edx),%rdi <-- trapping instruction
2f: 5b pop %rbx
30: 5d pop %rbp
31: 41 5c pop %r12
33: 41 5d pop %r13
35: 41 5e pop %r14
37: e9 85 3a a7 04 jmp 0x4a73ac1
3c: 48 89 de mov %rbx,%rsi
3f: 48 rex.W
---
This report is generated by a bot. It may contain errors.
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reply other threads:[~2026-08-01 0:45 UTC|newest]
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