tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1#!/bin/env python3
2# SPDX-License-Identifier: GPL-2.0
3# -*- coding: utf-8 -*-
4#
5# Copyright (c) 2021 Benjamin Tissoires <benjamin.tissoires@gmail.com>
6# Copyright (c) 2021 Red Hat, Inc.
7#
8
9# This is to ensure we don't crash when emulating USB devices
10
11from . import base
12import pytest
13import logging
14
15logger = logging.getLogger("hidtools.test.usb")
16
17
18class USBDev(base.UHIDTestDevice):
19 # fmt: off
20 report_descriptor = [
21 0x05, 0x01, # .Usage Page (Generic Desktop) 0
22 0x09, 0x02, # .Usage (Mouse) 2
23 0xa1, 0x01, # .Collection (Application) 4
24 0x09, 0x02, # ..Usage (Mouse) 6
25 0xa1, 0x02, # ..Collection (Logical) 8
26 0x09, 0x01, # ...Usage (Pointer) 10
27 0xa1, 0x00, # ...Collection (Physical) 12
28 0x05, 0x09, # ....Usage Page (Button) 14
29 0x19, 0x01, # ....Usage Minimum (1) 16
30 0x29, 0x03, # ....Usage Maximum (3) 18
31 0x15, 0x00, # ....Logical Minimum (0) 20
32 0x25, 0x01, # ....Logical Maximum (1) 22
33 0x75, 0x01, # ....Report Size (1) 24
34 0x95, 0x03, # ....Report Count (3) 26
35 0x81, 0x02, # ....Input (Data,Var,Abs) 28
36 0x75, 0x05, # ....Report Size (5) 30
37 0x95, 0x01, # ....Report Count (1) 32
38 0x81, 0x03, # ....Input (Cnst,Var,Abs) 34
39 0x05, 0x01, # ....Usage Page (Generic Desktop) 36
40 0x09, 0x30, # ....Usage (X) 38
41 0x09, 0x31, # ....Usage (Y) 40
42 0x15, 0x81, # ....Logical Minimum (-127) 42
43 0x25, 0x7f, # ....Logical Maximum (127) 44
44 0x75, 0x08, # ....Report Size (8) 46
45 0x95, 0x02, # ....Report Count (2) 48
46 0x81, 0x06, # ....Input (Data,Var,Rel) 50
47 0xc0, # ...End Collection 52
48 0xc0, # ..End Collection 53
49 0xc0, # .End Collection 54
50 ]
51 # fmt: on
52
53 def __init__(self, name=None, input_info=None):
54 super().__init__(
55 name, "Mouse", input_info=input_info, rdesc=USBDev.report_descriptor
56 )
57
58 # skip witing for udev events, it's likely that the report
59 # descriptor is wrong
60 def is_ready(self):
61 return True
62
63 # we don't have an evdev node here, so paper over
64 # the checks
65 def get_evdev(self, application=None):
66 return "OK"
67
68
69class TestUSBDevice(base.BaseTestCase.TestUhid):
70 """
71 Test class to test if an emulated USB device crashes
72 the kernel.
73 """
74
75 # conftest.py is generating the following fixture:
76 #
77 # @pytest.fixture(params=[('modulename', 1, 2)])
78 # def usbVidPid(self, request):
79 # return request.param
80
81 @pytest.fixture()
82 def new_uhdev(self, usbVidPid, request):
83 self.module, self.vid, self.pid = usbVidPid
84 self._load_kernel_module(None, self.module)
85 return USBDev(input_info=(3, self.vid, self.pid))
86
87 def test_creation(self):
88 """
89 inject the USB dev through uhid and immediately see if there is a crash:
90
91 uhid can create a USB device with the BUS_USB bus, and some
92 drivers assume that they can then access USB related structures
93 when they are actually provided a uhid device. This leads to
94 a crash because those access result in a segmentation fault.
95
96 The kernel should not crash on any (random) user space correct
97 use of its API. So run through all available modules and declared
98 devices to see if we can generate a uhid device without a crash.
99
100 The test is empty as the fixture `check_taint` is doing the job (and
101 honestly, when the kernel crashes, the whole machine freezes).
102 """
103 assert True