linux/drivers/hid/hid-dr.c
Alan Stern d9d4b1e46d HID: Fix assumption that devices have inputs
The syzbot fuzzer found a slab-out-of-bounds write bug in the hid-gaff
driver.  The problem is caused by the driver's assumption that the
device must have an input report.  While this will be true for all
normal HID input devices, a suitably malicious device can violate the
assumption.

The same assumption is present in over a dozen other HID drivers.
This patch fixes them by checking that the list of hid_inputs for the
hid_device is nonempty before allowing it to be used.

Reported-and-tested-by: syzbot+403741a091bf41d4ae79@syzkaller.appspotmail.com
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
CC: <stable@vger.kernel.org>
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
2019-10-03 15:36:40 -04:00

320 lines
9.1 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Force feedback support for DragonRise Inc. game controllers
*
* From what I have gathered, these devices are mass produced in China and are
* distributed under several vendors. They often share the same design as
* the original PlayStation DualShock controller.
*
* 0079:0006 "DragonRise Inc. Generic USB Joystick "
* - tested with a Tesun USB-703 game controller.
*
* Copyright (c) 2009 Richard Walmsley <richwalm@gmail.com>
*/
/*
*/
#include <linux/input.h>
#include <linux/slab.h>
#include <linux/hid.h>
#include <linux/module.h>
#include "hid-ids.h"
#ifdef CONFIG_DRAGONRISE_FF
struct drff_device {
struct hid_report *report;
};
static int drff_play(struct input_dev *dev, void *data,
struct ff_effect *effect)
{
struct hid_device *hid = input_get_drvdata(dev);
struct drff_device *drff = data;
int strong, weak;
strong = effect->u.rumble.strong_magnitude;
weak = effect->u.rumble.weak_magnitude;
dbg_hid("called with 0x%04x 0x%04x", strong, weak);
if (strong || weak) {
strong = strong * 0xff / 0xffff;
weak = weak * 0xff / 0xffff;
/* While reverse engineering this device, I found that when
this value is set, it causes the strong rumble to function
at a near maximum speed, so we'll bypass it. */
if (weak == 0x0a)
weak = 0x0b;
drff->report->field[0]->value[0] = 0x51;
drff->report->field[0]->value[1] = 0x00;
drff->report->field[0]->value[2] = weak;
drff->report->field[0]->value[4] = strong;
hid_hw_request(hid, drff->report, HID_REQ_SET_REPORT);
drff->report->field[0]->value[0] = 0xfa;
drff->report->field[0]->value[1] = 0xfe;
} else {
drff->report->field[0]->value[0] = 0xf3;
drff->report->field[0]->value[1] = 0x00;
}
drff->report->field[0]->value[2] = 0x00;
drff->report->field[0]->value[4] = 0x00;
dbg_hid("running with 0x%02x 0x%02x", strong, weak);
hid_hw_request(hid, drff->report, HID_REQ_SET_REPORT);
return 0;
}
static int drff_init(struct hid_device *hid)
{
struct drff_device *drff;
struct hid_report *report;
struct hid_input *hidinput;
struct list_head *report_list =
&hid->report_enum[HID_OUTPUT_REPORT].report_list;
struct input_dev *dev;
int error;
if (list_empty(&hid->inputs)) {
hid_err(hid, "no inputs found\n");
return -ENODEV;
}
hidinput = list_first_entry(&hid->inputs, struct hid_input, list);
dev = hidinput->input;
if (list_empty(report_list)) {
hid_err(hid, "no output reports found\n");
return -ENODEV;
}
report = list_first_entry(report_list, struct hid_report, list);
if (report->maxfield < 1) {
hid_err(hid, "no fields in the report\n");
return -ENODEV;
}
if (report->field[0]->report_count < 7) {
hid_err(hid, "not enough values in the field\n");
return -ENODEV;
}
drff = kzalloc(sizeof(struct drff_device), GFP_KERNEL);
if (!drff)
return -ENOMEM;
set_bit(FF_RUMBLE, dev->ffbit);
error = input_ff_create_memless(dev, drff, drff_play);
if (error) {
kfree(drff);
return error;
}
drff->report = report;
drff->report->field[0]->value[0] = 0xf3;
drff->report->field[0]->value[1] = 0x00;
drff->report->field[0]->value[2] = 0x00;
drff->report->field[0]->value[3] = 0x00;
drff->report->field[0]->value[4] = 0x00;
drff->report->field[0]->value[5] = 0x00;
drff->report->field[0]->value[6] = 0x00;
hid_hw_request(hid, drff->report, HID_REQ_SET_REPORT);
hid_info(hid, "Force Feedback for DragonRise Inc. "
"game controllers by Richard Walmsley <richwalm@gmail.com>\n");
return 0;
}
#else
static inline int drff_init(struct hid_device *hid)
{
return 0;
}
#endif
/*
* The original descriptor of joystick with PID 0x0011, represented by DVTech PC
* JS19. It seems both copied from another device and a result of confusion
* either about the specification or about the program used to create the
* descriptor. In any case, it's a wonder it works on Windows.
*
* Usage Page (Desktop), ; Generic desktop controls (01h)
* Usage (Joystick), ; Joystick (04h, application collection)
* Collection (Application),
* Collection (Logical),
* Report Size (8),
* Report Count (5),
* Logical Minimum (0),
* Logical Maximum (255),
* Physical Minimum (0),
* Physical Maximum (255),
* Usage (X), ; X (30h, dynamic value)
* Usage (X), ; X (30h, dynamic value)
* Usage (X), ; X (30h, dynamic value)
* Usage (X), ; X (30h, dynamic value)
* Usage (Y), ; Y (31h, dynamic value)
* Input (Variable),
* Report Size (4),
* Report Count (1),
* Logical Maximum (7),
* Physical Maximum (315),
* Unit (Degrees),
* Usage (00h),
* Input (Variable, Null State),
* Unit,
* Report Size (1),
* Report Count (10),
* Logical Maximum (1),
* Physical Maximum (1),
* Usage Page (Button), ; Button (09h)
* Usage Minimum (01h),
* Usage Maximum (0Ah),
* Input (Variable),
* Usage Page (FF00h), ; FF00h, vendor-defined
* Report Size (1),
* Report Count (10),
* Logical Maximum (1),
* Physical Maximum (1),
* Usage (01h),
* Input (Variable),
* End Collection,
* Collection (Logical),
* Report Size (8),
* Report Count (4),
* Physical Maximum (255),
* Logical Maximum (255),
* Usage (02h),
* Output (Variable),
* End Collection,
* End Collection
*/
/* Size of the original descriptor of the PID 0x0011 joystick */
#define PID0011_RDESC_ORIG_SIZE 101
/* Fixed report descriptor for PID 0x011 joystick */
static __u8 pid0011_rdesc_fixed[] = {
0x05, 0x01, /* Usage Page (Desktop), */
0x09, 0x04, /* Usage (Joystick), */
0xA1, 0x01, /* Collection (Application), */
0xA1, 0x02, /* Collection (Logical), */
0x14, /* Logical Minimum (0), */
0x75, 0x08, /* Report Size (8), */
0x95, 0x03, /* Report Count (3), */
0x81, 0x01, /* Input (Constant), */
0x26, 0xFF, 0x00, /* Logical Maximum (255), */
0x95, 0x02, /* Report Count (2), */
0x09, 0x30, /* Usage (X), */
0x09, 0x31, /* Usage (Y), */
0x81, 0x02, /* Input (Variable), */
0x75, 0x01, /* Report Size (1), */
0x95, 0x04, /* Report Count (4), */
0x81, 0x01, /* Input (Constant), */
0x25, 0x01, /* Logical Maximum (1), */
0x95, 0x0A, /* Report Count (10), */
0x05, 0x09, /* Usage Page (Button), */
0x19, 0x01, /* Usage Minimum (01h), */
0x29, 0x0A, /* Usage Maximum (0Ah), */
0x81, 0x02, /* Input (Variable), */
0x95, 0x0A, /* Report Count (10), */
0x81, 0x01, /* Input (Constant), */
0xC0, /* End Collection, */
0xC0 /* End Collection */
};
static __u8 *dr_report_fixup(struct hid_device *hdev, __u8 *rdesc,
unsigned int *rsize)
{
switch (hdev->product) {
case 0x0011:
if (*rsize == PID0011_RDESC_ORIG_SIZE) {
rdesc = pid0011_rdesc_fixed;
*rsize = sizeof(pid0011_rdesc_fixed);
}
break;
}
return rdesc;
}
#define map_abs(c) hid_map_usage(hi, usage, bit, max, EV_ABS, (c))
#define map_rel(c) hid_map_usage(hi, usage, bit, max, EV_REL, (c))
static int dr_input_mapping(struct hid_device *hdev, struct hid_input *hi,
struct hid_field *field, struct hid_usage *usage,
unsigned long **bit, int *max)
{
switch (usage->hid) {
/*
* revert to the old hid-input behavior where axes
* can be randomly assigned when hid->usage is reused.
*/
case HID_GD_X: case HID_GD_Y: case HID_GD_Z:
case HID_GD_RX: case HID_GD_RY: case HID_GD_RZ:
if (field->flags & HID_MAIN_ITEM_RELATIVE)
map_rel(usage->hid & 0xf);
else
map_abs(usage->hid & 0xf);
return 1;
}
return 0;
}
static int dr_probe(struct hid_device *hdev, const struct hid_device_id *id)
{
int ret;
dev_dbg(&hdev->dev, "DragonRise Inc. HID hardware probe...");
ret = hid_parse(hdev);
if (ret) {
hid_err(hdev, "parse failed\n");
goto err;
}
ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT & ~HID_CONNECT_FF);
if (ret) {
hid_err(hdev, "hw start failed\n");
goto err;
}
switch (hdev->product) {
case 0x0006:
ret = drff_init(hdev);
if (ret) {
dev_err(&hdev->dev, "force feedback init failed\n");
hid_hw_stop(hdev);
goto err;
}
break;
}
return 0;
err:
return ret;
}
static const struct hid_device_id dr_devices[] = {
{ HID_USB_DEVICE(USB_VENDOR_ID_DRAGONRISE, 0x0006), },
{ HID_USB_DEVICE(USB_VENDOR_ID_DRAGONRISE, 0x0011), },
{ }
};
MODULE_DEVICE_TABLE(hid, dr_devices);
static struct hid_driver dr_driver = {
.name = "dragonrise",
.id_table = dr_devices,
.report_fixup = dr_report_fixup,
.probe = dr_probe,
.input_mapping = dr_input_mapping,
};
module_hid_driver(dr_driver);
MODULE_LICENSE("GPL");