u-boot/drivers/usb/emul/usb-emul-uclass.c
Andrew Scull 62120155b6 usb: sandbox: Check for string end in copy_to_unicode()
When copying the string in copy_to_unicode(), check for the null
terminator in each position, not just at the start, to avoid reading
beyond the end of the string.

Signed-off-by: Andrew Scull <ascull@google.com>
Cc: Simon Glass <sjg@chromium.org>
Cc: Marek Vasut <marex@denx.de>
Reviewed-by: Simon Glass <sjg@chromium.org>
2022-04-29 11:11:36 -04:00

305 lines
7.4 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* (C) Copyright 2015 Google, Inc
* Written by Simon Glass <sjg@chromium.org>
*/
#define LOG_CATEGORY UCLASS_USB_EMUL
#include <common.h>
#include <dm.h>
#include <log.h>
#include <usb.h>
#include <dm/device-internal.h>
static int copy_to_unicode(char *buff, int length, const char *str)
{
int ptr;
if (length < 2)
return 0;
buff[1] = USB_DT_STRING;
for (ptr = 2; ptr + 1 < length && *str; str++, ptr += 2) {
buff[ptr] = *str;
buff[ptr + 1] = 0;
}
buff[0] = ptr;
return ptr;
}
static int usb_emul_get_string(struct usb_string *strings, int index,
char *buff, int length)
{
if (index == 0) {
char *desc = buff;
desc[0] = 4;
desc[1] = USB_DT_STRING;
desc[2] = 0x09;
desc[3] = 0x14;
return 4;
} else if (strings) {
struct usb_string *ptr;
for (ptr = strings; ptr->s; ptr++) {
if (ptr->id == index)
return copy_to_unicode(buff, length, ptr->s);
}
}
return -EINVAL;
}
struct usb_generic_descriptor **usb_emul_find_descriptor(
struct usb_generic_descriptor **ptr, int type, int index)
{
debug("%s: type=%x, index=%d\n", __func__, type, index);
for (; *ptr; ptr++) {
if ((*ptr)->bDescriptorType != type)
continue;
switch (type) {
case USB_DT_CONFIG: {
struct usb_config_descriptor *cdesc;
cdesc = (struct usb_config_descriptor *)*ptr;
if (cdesc && cdesc->bConfigurationValue == index)
return ptr;
break;
}
default:
return ptr;
}
}
debug("%s: config ptr=%p\n", __func__, *ptr);
return ptr;
}
static int usb_emul_get_descriptor(struct usb_dev_plat *plat, int value,
void *buffer, int length)
{
struct usb_generic_descriptor **ptr;
int type = value >> 8;
int index = value & 0xff;
int upto, todo;
debug("%s: type=%d, index=%d, plat=%p\n", __func__, type, index, plat);
if (type == USB_DT_STRING) {
return usb_emul_get_string(plat->strings, index, buffer,
length);
}
ptr = usb_emul_find_descriptor(plat->desc_list, type, index);
if (!ptr) {
debug("%s: Could not find descriptor type %d, index %d\n",
__func__, type, index);
return -ENOENT;
}
for (upto = 0; *ptr && upto < length; ptr++, upto += todo) {
todo = min(length - upto, (int)(*ptr)->bLength);
memcpy(buffer + upto, *ptr, todo);
}
return upto ? upto : length ? -EIO : 0;
}
static int usb_emul_find_devnum(int devnum, int port1, struct udevice **emulp)
{
struct udevice *dev;
struct uclass *uc;
int ret;
*emulp = NULL;
ret = uclass_get(UCLASS_USB_EMUL, &uc);
if (ret)
return ret;
uclass_foreach_dev(dev, uc) {
struct usb_dev_plat *udev = dev_get_parent_plat(dev);
/*
* devnum is initialzied to zero at the beginning of the
* enumeration process in usb_setup_device(). At this
* point, udev->devnum has not been assigned to any valid
* USB address either, so we can't rely on the comparison
* result between udev->devnum and devnum to select an
* emulator device.
*/
if (!devnum) {
struct usb_emul_plat *plat;
/*
* If the parent is sandbox USB controller, we are
* the root hub. And there is only one root hub
* in the system.
*/
if (device_get_uclass_id(dev->parent) == UCLASS_USB) {
debug("%s: Found emulator '%s'\n",
__func__, dev->name);
*emulp = dev;
return 0;
}
plat = dev_get_uclass_plat(dev);
if (plat->port1 == port1) {
debug("%s: Found emulator '%s', port %d\n",
__func__, dev->name, port1);
*emulp = dev;
return 0;
}
} else if (udev->devnum == devnum) {
debug("%s: Found emulator '%s', addr %d\n", __func__,
dev->name, udev->devnum);
*emulp = dev;
return 0;
}
}
debug("%s: No emulator found, addr %d\n", __func__, devnum);
return -ENOENT;
}
int usb_emul_find(struct udevice *bus, ulong pipe, int port1,
struct udevice **emulp)
{
int devnum = usb_pipedevice(pipe);
return usb_emul_find_devnum(devnum, port1, emulp);
}
int usb_emul_find_for_dev(struct udevice *dev, struct udevice **emulp)
{
struct usb_dev_plat *udev = dev_get_parent_plat(dev);
return usb_emul_find_devnum(udev->devnum, 0, emulp);
}
int usb_emul_control(struct udevice *emul, struct usb_device *udev,
unsigned long pipe, void *buffer, int length,
struct devrequest *setup)
{
struct dm_usb_ops *ops = usb_get_emul_ops(emul);
struct usb_dev_plat *plat;
int ret;
/* We permit getting the descriptor before we are probed */
plat = dev_get_parent_plat(emul);
if (!ops->control)
return -ENOSYS;
debug("%s: dev=%s\n", __func__, emul->name);
if (pipe == usb_rcvctrlpipe(udev, 0)) {
switch (setup->request) {
case USB_REQ_GET_DESCRIPTOR: {
return usb_emul_get_descriptor(plat, setup->value,
buffer, length);
}
default:
ret = device_probe(emul);
if (ret)
return ret;
return ops->control(emul, udev, pipe, buffer, length,
setup);
}
} else if (pipe == usb_snddefctrl(udev)) {
switch (setup->request) {
case USB_REQ_SET_ADDRESS:
debug(" ** set address %s %d\n", emul->name,
setup->value);
plat->devnum = setup->value;
return 0;
default:
debug("requestsend =%x\n", setup->request);
break;
}
} else if (pipe == usb_sndctrlpipe(udev, 0)) {
switch (setup->request) {
case USB_REQ_SET_CONFIGURATION:
plat->configno = setup->value;
return 0;
default:
ret = device_probe(emul);
if (ret)
return ret;
return ops->control(emul, udev, pipe, buffer, length,
setup);
}
}
debug("pipe=%lx\n", pipe);
return -EIO;
}
int usb_emul_bulk(struct udevice *emul, struct usb_device *udev,
unsigned long pipe, void *buffer, int length)
{
struct dm_usb_ops *ops = usb_get_emul_ops(emul);
int ret;
/* We permit getting the descriptor before we are probed */
if (!ops->bulk)
return -ENOSYS;
debug("%s: dev=%s\n", __func__, emul->name);
ret = device_probe(emul);
if (ret)
return ret;
return ops->bulk(emul, udev, pipe, buffer, length);
}
int usb_emul_int(struct udevice *emul, struct usb_device *udev,
unsigned long pipe, void *buffer, int length, int interval,
bool nonblock)
{
struct dm_usb_ops *ops = usb_get_emul_ops(emul);
if (!ops->interrupt)
return -ENOSYS;
debug("%s: dev=%s\n", __func__, emul->name);
return ops->interrupt(emul, udev, pipe, buffer, length, interval,
nonblock);
}
int usb_emul_setup_device(struct udevice *dev, struct usb_string *strings,
void **desc_list)
{
struct usb_dev_plat *plat = dev_get_parent_plat(dev);
struct usb_generic_descriptor **ptr;
struct usb_config_descriptor *cdesc;
int upto;
plat->strings = strings;
plat->desc_list = (struct usb_generic_descriptor **)desc_list;
/* Fill in wTotalLength for each configuration descriptor */
ptr = plat->desc_list;
for (cdesc = NULL, upto = 0; *ptr; upto += (*ptr)->bLength, ptr++) {
debug(" - upto=%d, type=%d\n", upto, (*ptr)->bDescriptorType);
if ((*ptr)->bDescriptorType == USB_DT_CONFIG) {
if (cdesc) {
cdesc->wTotalLength = upto;
debug("%s: config %d length %d\n", __func__,
cdesc->bConfigurationValue,
cdesc->bLength);
}
cdesc = (struct usb_config_descriptor *)*ptr;
upto = 0;
}
}
if (cdesc) {
cdesc->wTotalLength = upto;
debug("%s: config %d length %d\n", __func__,
cdesc->bConfigurationValue, cdesc->wTotalLength);
}
return 0;
}
UCLASS_DRIVER(usb_emul) = {
.id = UCLASS_USB_EMUL,
.name = "usb_emul",
.post_bind = dm_scan_fdt_dev,
.per_device_plat_auto = sizeof(struct usb_emul_plat),
.per_child_auto = sizeof(struct usb_device),
.per_child_plat_auto = sizeof(struct usb_dev_plat),
};