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USB: check usb_get_extra_descriptor for proper size

When reading an extra descriptor, we need to properly check the minimum
and maximum size allowed, to prevent from invalid data being sent by a
device.

Reported-by: Hui Peng <benquike@gmail.com>
Reported-by: Mathias Payer <mathias.payer@nebelwelt.net>
Co-developed-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Hui Peng <benquike@gmail.com>
Signed-off-by: Mathias Payer <mathias.payer@nebelwelt.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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gannimo authored and gregkh committed Dec 5, 2018
1 parent 2f2dde6 commit 704620afc70cf47abb9d6a1a57f3825d2bca49cf
Showing with 7 additions and 7 deletions.
  1. +1 −1 drivers/usb/core/hub.c
  2. +3 −3 drivers/usb/core/usb.c
  3. +1 −1 drivers/usb/host/hwa-hc.c
  4. +2 −2 include/linux/usb.h
@@ -2251,7 +2251,7 @@ static int usb_enumerate_device_otg(struct usb_device *udev)
/* descriptor may appear anywhere in config */
err = __usb_get_extra_descriptor(udev->rawdescriptors[0],
le16_to_cpu(udev->config[0].desc.wTotalLength),
USB_DT_OTG, (void **) &desc);
USB_DT_OTG, (void **) &desc, sizeof(*desc));
if (err || !(desc->bmAttributes & USB_OTG_HNP))
return 0;

@@ -832,14 +832,14 @@ EXPORT_SYMBOL_GPL(usb_get_current_frame_number);
*/

int __usb_get_extra_descriptor(char *buffer, unsigned size,
unsigned char type, void **ptr)
unsigned char type, void **ptr, size_t minsize)
{
struct usb_descriptor_header *header;

while (size >= sizeof(struct usb_descriptor_header)) {
header = (struct usb_descriptor_header *)buffer;

if (header->bLength < 2) {
if (header->bLength < 2 || header->bLength > size) {
printk(KERN_ERR
"%s: bogus descriptor, type %d length %d\n",
usbcore_name,
@@ -848,7 +848,7 @@ int __usb_get_extra_descriptor(char *buffer, unsigned size,
return -1;
}

if (header->bDescriptorType == type) {
if (header->bDescriptorType == type && header->bLength >= minsize) {
*ptr = header;
return 0;
}
@@ -640,7 +640,7 @@ static int hwahc_security_create(struct hwahc *hwahc)
top = itr + itr_size;
result = __usb_get_extra_descriptor(usb_dev->rawdescriptors[index],
le16_to_cpu(usb_dev->actconfig->desc.wTotalLength),
USB_DT_SECURITY, (void **) &secd);
USB_DT_SECURITY, (void **) &secd, sizeof(*secd));
if (result == -1) {
dev_warn(dev, "BUG? WUSB host has no security descriptors\n");
return 0;
@@ -407,11 +407,11 @@ struct usb_host_bos {
};

int __usb_get_extra_descriptor(char *buffer, unsigned size,
unsigned char type, void **ptr);
unsigned char type, void **ptr, size_t min);
#define usb_get_extra_descriptor(ifpoint, type, ptr) \
__usb_get_extra_descriptor((ifpoint)->extra, \
(ifpoint)->extralen, \
type, (void **)ptr)
type, (void **)ptr, sizeof(**(ptr)))

/* ----------------------------------------------------------------------- */

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