mirror of
https://github.com/torvalds/linux.git
synced 2024-11-15 00:21:59 +00:00
d9d4b1e46d
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>
149 lines
3.2 KiB
C
149 lines
3.2 KiB
C
// SPDX-License-Identifier: GPL-2.0-or-later
|
|
/*
|
|
* Force feedback support for EMS Trio Linker Plus II
|
|
*
|
|
* Copyright (c) 2010 Ignaz Forster <ignaz.forster@gmx.de>
|
|
*/
|
|
|
|
/*
|
|
*/
|
|
|
|
|
|
#include <linux/hid.h>
|
|
#include <linux/input.h>
|
|
#include <linux/module.h>
|
|
|
|
#include "hid-ids.h"
|
|
|
|
struct emsff_device {
|
|
struct hid_report *report;
|
|
};
|
|
|
|
static int emsff_play(struct input_dev *dev, void *data,
|
|
struct ff_effect *effect)
|
|
{
|
|
struct hid_device *hid = input_get_drvdata(dev);
|
|
struct emsff_device *emsff = data;
|
|
int weak, strong;
|
|
|
|
weak = effect->u.rumble.weak_magnitude;
|
|
strong = effect->u.rumble.strong_magnitude;
|
|
|
|
dbg_hid("called with 0x%04x 0x%04x\n", strong, weak);
|
|
|
|
weak = weak * 0xff / 0xffff;
|
|
strong = strong * 0xff / 0xffff;
|
|
|
|
emsff->report->field[0]->value[1] = weak;
|
|
emsff->report->field[0]->value[2] = strong;
|
|
|
|
dbg_hid("running with 0x%02x 0x%02x\n", strong, weak);
|
|
hid_hw_request(hid, emsff->report, HID_REQ_SET_REPORT);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int emsff_init(struct hid_device *hid)
|
|
{
|
|
struct emsff_device *emsff;
|
|
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;
|
|
}
|
|
|
|
emsff = kzalloc(sizeof(struct emsff_device), GFP_KERNEL);
|
|
if (!emsff)
|
|
return -ENOMEM;
|
|
|
|
set_bit(FF_RUMBLE, dev->ffbit);
|
|
|
|
error = input_ff_create_memless(dev, emsff, emsff_play);
|
|
if (error) {
|
|
kfree(emsff);
|
|
return error;
|
|
}
|
|
|
|
emsff->report = report;
|
|
emsff->report->field[0]->value[0] = 0x01;
|
|
emsff->report->field[0]->value[1] = 0x00;
|
|
emsff->report->field[0]->value[2] = 0x00;
|
|
emsff->report->field[0]->value[3] = 0x00;
|
|
emsff->report->field[0]->value[4] = 0x00;
|
|
emsff->report->field[0]->value[5] = 0x00;
|
|
emsff->report->field[0]->value[6] = 0x00;
|
|
hid_hw_request(hid, emsff->report, HID_REQ_SET_REPORT);
|
|
|
|
hid_info(hid, "force feedback for EMS based devices by Ignaz Forster <ignaz.forster@gmx.de>\n");
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int ems_probe(struct hid_device *hdev, const struct hid_device_id *id)
|
|
{
|
|
int ret;
|
|
|
|
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;
|
|
}
|
|
|
|
ret = emsff_init(hdev);
|
|
if (ret) {
|
|
dev_err(&hdev->dev, "force feedback init failed\n");
|
|
hid_hw_stop(hdev);
|
|
goto err;
|
|
}
|
|
|
|
return 0;
|
|
err:
|
|
return ret;
|
|
}
|
|
|
|
static const struct hid_device_id ems_devices[] = {
|
|
{ HID_USB_DEVICE(USB_VENDOR_ID_EMS, USB_DEVICE_ID_EMS_TRIO_LINKER_PLUS_II) },
|
|
{ }
|
|
};
|
|
MODULE_DEVICE_TABLE(hid, ems_devices);
|
|
|
|
static struct hid_driver ems_driver = {
|
|
.name = "hkems",
|
|
.id_table = ems_devices,
|
|
.probe = ems_probe,
|
|
};
|
|
module_hid_driver(ems_driver);
|
|
|
|
MODULE_LICENSE("GPL");
|
|
|