This patch makes config.c more liberal about the sorts of interface
numbering it will accept when reading interface descriptors. The current
code only allows interfaces numbered 0..(bNumInterfaces-1), but a number
of devices erroneously number their interfaces starting at 1.
With this patch, the code will accept a total of bNumInterfaces with
numbers in the interval 0..bNumInterfaces. That will accomodate origin-1
indexing (and a few other things beside). Also included is a comment in
include/linux/usb.h warning people that the interface numbers might not
correspond to the locations in the usb_host_config->interface[] array and
telling them they should use usb_ifnum_to_if().
Lauri, can you try this out and see if it helps with your prism2_usb?
Alan Stern
===== drivers/usb/core/config.c 1.28 vs edited =====
--- 1.28/drivers/usb/core/config.c Fri Sep 26 12:37:44 2003
+++ edited/drivers/usb/core/config.c Mon Oct 27 09:52:20 2003
@@ -8,9 +8,7 @@
#define USB_MAXALTSETTING 128 /* Hard limit */
#define USB_MAXENDPOINTS 30 /* Hard limit */
-/* these maximums are arbitrary */
-#define USB_MAXCONFIG 8
-#define USB_MAXINTERFACES 32
+#define USB_MAXCONFIG 8 /* Arbitrary limit */
static int usb_parse_endpoint(struct usb_host_endpoint *endpoint, unsigned char
*buffer, int size)
{
@@ -90,7 +88,8 @@
kfree(intf);
}
-static int usb_parse_interface(struct usb_host_config *config, unsigned char *buffer,
int size)
+static int usb_parse_interface(struct usb_host_config *config,
+ unsigned char *buffer, int size, u8 inums[])
{
unsigned char *buffer0 = buffer;
struct usb_interface_descriptor *d;
@@ -109,8 +108,15 @@
return -EINVAL;
}
+ interface = NULL;
inum = d->bInterfaceNumber;
- if (inum >= config->desc.bNumInterfaces) {
+ for (i = 0; i < config->desc.bNumInterfaces; ++i) {
+ if (inums[i] == inum) {
+ interface = config->interface[i];
+ break;
+ }
+ }
+ if (!interface) {
/* Skip to the next interface descriptor */
buffer += d->bLength;
@@ -126,7 +132,6 @@
return buffer - buffer0;
}
- interface = config->interface[inum];
asnum = d->bAlternateSetting;
if (asnum >= interface->num_altsetting) {
warn("invalid alternate setting %d for interface %d",
@@ -210,6 +215,8 @@
int numskipped, len;
char *begin;
int retval;
+ int n;
+ u8 inums[USB_MAXINTERFACES], nalts[USB_MAXINTERFACES];
memcpy(&config->desc, buffer, USB_DT_CONFIG_SIZE);
if (config->desc.bDescriptorType != USB_DT_CONFIG ||
@@ -225,25 +232,14 @@
nintf, USB_MAXINTERFACES);
config->desc.bNumInterfaces = nintf = USB_MAXINTERFACES;
}
-
- for (i = 0; i < nintf; ++i) {
- interface = config->interface[i] =
- kmalloc(sizeof(struct usb_interface), GFP_KERNEL);
- dbg("kmalloc IF %p, numif %i", interface, i);
- if (!interface) {
- err("out of memory");
- return -ENOMEM;
- }
- memset(interface, 0, sizeof(struct usb_interface));
- interface->dev.release = usb_release_intf;
- device_initialize(&interface->dev);
- }
+ if (nintf == 0)
+ warn("no interfaces?");
/* Go through the descriptors, checking their length and counting the
* number of altsettings for each interface */
+ n = 0;
buffer2 = buffer;
size2 = size;
- j = 0;
while (size2 >= sizeof(struct usb_descriptor_header)) {
header = (struct usb_descriptor_header *) buffer2;
if ((header->bLength > size2) || (header->bLength < 2)) {
@@ -253,42 +249,72 @@
if (header->bDescriptorType == USB_DT_INTERFACE) {
struct usb_interface_descriptor *d;
+ int inum;
if (header->bLength < USB_DT_INTERFACE_SIZE) {
warn("invalid interface descriptor");
return -EINVAL;
}
d = (struct usb_interface_descriptor *) header;
- i = d->bInterfaceNumber;
- if (i >= nintf_orig) {
+ inum = d->bInterfaceNumber;
+ if (inum > nintf_orig) {
warn("invalid interface number (%d/%d)",
- i, nintf_orig);
+ inum, nintf_orig);
+ return -EINVAL;
+ }
+
+ /* Insertion sort is slow but it works */
+ for (i = n - 1; i >= 0; --i) {
+ if (inums[i] < inum)
+ break;
+ }
+ if (++i < n && inums[i] == inum)
+ ++nalts[i];
+ else if (n >= nintf_orig) {
+ warn("too many interfaces (> %d)", nintf_orig);
return -EINVAL;
+ } else if (i < nintf) {
+ if (n < nintf)
+ ++n;
+ for (j = n-1; j > i; --j) {
+ inums[j] = inums[j-1];
+ nalts[j] = nalts[j-1];
+ }
+ inums[i] = inum;
+ nalts[i] = 1;
}
- if (i < nintf)
- ++config->interface[i]->num_altsetting;
} else if ((header->bDescriptorType == USB_DT_DEVICE ||
- header->bDescriptorType == USB_DT_CONFIG) && j) {
+ header->bDescriptorType == USB_DT_CONFIG) && buffer2 > buffer) {
warn("unexpected descriptor type 0x%X",
header->bDescriptorType);
return -EINVAL;
}
- j = 1;
buffer2 += header->bLength;
size2 -= header->bLength;
}
+ if (n < nintf) {
+ warn("not enough interfaces (%d/%d)", n, nintf);
+ return -EINVAL;
+ }
- /* Allocate the altsetting arrays */
- for (i = 0; i < config->desc.bNumInterfaces; ++i) {
- interface = config->interface[i];
+ /* Allocate the interfaces and altsetting arrays */
+ for (i = 0; i < nintf; ++i) {
+ interface = config->interface[i] =
+ kmalloc(sizeof(struct usb_interface), GFP_KERNEL);
+ dbg("kmalloc IF %p, numif %i", interface, i);
+ if (!interface) {
+ err("out of memory");
+ return -ENOMEM;
+ }
+ memset(interface, 0, sizeof(struct usb_interface));
+ interface->dev.release = usb_release_intf;
+ device_initialize(&interface->dev);
+
+ interface->num_altsetting = nalts[i];
if (interface->num_altsetting > USB_MAXALTSETTING) {
warn("too many alternate settings for interface %d (%d max
%d)\n",
- i, interface->num_altsetting, USB_MAXALTSETTING);
- return -EINVAL;
- }
- if (interface->num_altsetting == 0) {
- warn("no alternate settings for interface %d", i);
+ inums[i], interface->num_altsetting, USB_MAXALTSETTING);
return -EINVAL;
}
@@ -329,7 +355,7 @@
/* Parse all the interface/altsetting descriptors */
while (size >= sizeof(struct usb_descriptor_header)) {
- retval = usb_parse_interface(config, buffer, size);
+ retval = usb_parse_interface(config, buffer, size, inums);
if (retval < 0)
return retval;
===== include/linux/usb.h 1.164 vs edited =====
--- 1.164/include/linux/usb.h Mon Oct 6 13:46:13 2003
+++ edited/include/linux/usb.h Mon Oct 27 10:02:27 2003
@@ -75,7 +75,7 @@
* @altsetting: array of interface descriptors, one for each alternate
* setting that may be selected. Each one includes a set of
* endpoint configurations and will be in numberic order,
- * 0..num_altsetting.
+ * 0..num_altsetting-1.
* @num_altsetting: number of altsettings defined.
* @act_altsetting: index of current altsetting. this number is always
* less than num_altsetting. after the device is configured, each
@@ -111,7 +111,7 @@
*/
struct usb_interface {
/* array of alternate settings for this interface.
- * these will be in numeric order, 0..num_altsettting
+ * these will be in numeric order, 0..num_altsetting-1
*/
struct usb_host_interface *altsetting;
@@ -150,8 +150,12 @@
struct usb_host_config {
struct usb_config_descriptor desc;
- /* the interfaces associated with this configuration
- * these will be in numeric order, 0..desc.bNumInterfaces
+ /* The interfaces associated with this configuration.
+ * There are desc.bNumInterfaces of them, and they are
+ * in numeric order. But some non-compliant devices
+ * number the interfaces starting with 1, not 0. To be
+ * safe don't index this array directly; instead use
+ * usb_ifnum_to_if().
*/
struct usb_interface *interface[USB_MAXINTERFACES];
-------------------------------------------------------
This SF.net email is sponsored by: The SF.net Donation Program.
Do you like what SourceForge.net is doing for the Open
Source Community? Make a contribution, and help us add new
features and functionality. Click here: http://sourceforge.net/donate/
_______________________________________________
[EMAIL PROTECTED]
To unsubscribe, use the last form field at:
https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
