X-Git-Url: http://git.ipfire.org/?a=blobdiff_plain;f=drivers%2Fusb%2Fcore%2Fdevio.c;h=401300f0f36f2f53de2fedb02ad7f6f2c114a7c6;hb=63d9c273d7fae69ca6908d2668af0e508b99ea91;hp=e500243803d87b1b3882acb5d37670af48f43f1b;hpb=660613d1a4e94144490850b6c3d350331860fac4;p=people%2Fms%2Flinux.git

diff --git a/drivers/usb/core/devio.c b/drivers/usb/core/devio.c
index e500243803d8..401300f0f36f 100644
--- a/drivers/usb/core/devio.c
+++ b/drivers/usb/core/devio.c
@@ -187,7 +187,7 @@ static ssize_t usbdev_read(struct file *file, char __user *buf, size_t nbytes,
 	struct usb_dev_state *ps = file->private_data;
 	struct usb_device *dev = ps->dev;
 	ssize_t ret = 0;
-	unsigned len;
+	size_t len;
 	loff_t pos;
 	int i;
 
@@ -229,22 +229,22 @@ static ssize_t usbdev_read(struct file *file, char __user *buf, size_t nbytes,
 	for (i = 0; nbytes && i < dev->descriptor.bNumConfigurations; i++) {
 		struct usb_config_descriptor *config =
 			(struct usb_config_descriptor *)dev->rawdescriptors[i];
-		unsigned int length = le16_to_cpu(config->wTotalLength);
+		size_t length = le16_to_cpu(config->wTotalLength);
 
 		if (*ppos < pos + length) {
 
 			/* The descriptor may claim to be longer than it
 			 * really is.  Here is the actual allocated length. */
-			unsigned alloclen =
+			size_t alloclen =
 				le16_to_cpu(dev->config[i].desc.wTotalLength);
 
-			len = length - (*ppos - pos);
+			len = length + pos - *ppos;
 			if (len > nbytes)
 				len = nbytes;
 
 			/* Simply don't write (skip over) unallocated parts */
 			if (alloclen > (*ppos - pos)) {
-				alloclen -= (*ppos - pos);
+				alloclen = alloclen + pos - *ppos;
 				if (copy_to_user(buf,
 				    dev->rawdescriptors[i] + (*ppos - pos),
 				    min(len, alloclen))) {