1 files changed, 43 insertions, 14 deletions

diff --git a/drivers/usb/gadget/function/f_printer.c b/drivers/usb/gadget/function/f_printer.c
index 8054da9276dd..8df244fc9d80 100644
--- a/drivers/usb/gadget/function/f_printer.c
+++ b/drivers/usb/gadget/function/f_printer.c
@@ -49,7 +49,6 @@
 
 #include "u_printer.h"
 
-#define PNP_STRING_LEN		1024
 #define PRINTER_MINORS		4
 #define GET_DEVICE_ID		0
 #define GET_PORT_STATUS		1
@@ -907,8 +906,7 @@ static bool gprinter_req_match(struct usb_function *f,
 	switch (ctrl->bRequest) {
 	case GET_DEVICE_ID:
 		w_index >>= 8;
-		if (w_length <= PNP_STRING_LEN &&
-		    (USB_DIR_IN & ctrl->bRequestType))
+		if (USB_DIR_IN & ctrl->bRequestType)
 			break;
 		return false;
 	case GET_PORT_STATUS:
@@ -937,6 +935,7 @@ static int printer_func_setup(struct usb_function *f,
 	struct printer_dev *dev = func_to_printer(f);
 	struct usb_composite_dev *cdev = f->config->cdev;
 	struct usb_request	*req = cdev->req;
+	u8			*buf = req->buf;
 	int			value = -EOPNOTSUPP;
 	u16			wIndex = le16_to_cpu(ctrl->wIndex);
 	u16			wValue = le16_to_cpu(ctrl->wValue);
@@ -953,10 +952,16 @@ static int printer_func_setup(struct usb_function *f,
 			if ((wIndex>>8) != dev->interface)
 				break;
 
-			value = (dev->pnp_string[0] << 8) | dev->pnp_string[1];
-			memcpy(req->buf, dev->pnp_string, value);
+			if (!dev->pnp_string) {
+				value = 0;
+				break;
+			}
+			value = strlen(dev->pnp_string);
+			buf[0] = (value >> 8) & 0xFF;
+			buf[1] = value & 0xFF;
+			memcpy(buf + 2, dev->pnp_string, value);
 			DBG(dev, "1284 PNP String: %x %s\n", value,
-					&dev->pnp_string[2]);
+			    dev->pnp_string);
 			break;
 
 		case GET_PORT_STATUS: /* Get Port Status */
@@ -964,7 +969,7 @@ static int printer_func_setup(struct usb_function *f,
 			if (wIndex != dev->interface)
 				break;
 
-			*(u8 *)req->buf = dev->printer_status;
+			buf[0] = dev->printer_status;
 			value = min_t(u16, wLength, 1);
 			break;
 
@@ -1157,10 +1162,21 @@ static ssize_t f_printer_opts_pnp_string_show(struct config_item *item,
 					      char *page)
 {
 	struct f_printer_opts *opts = to_f_printer_opts(item);
-	int result;
+	int result = 0;
 
 	mutex_lock(&opts->lock);
-	result = strlcpy(page, opts->pnp_string + 2, PNP_STRING_LEN - 2);
+	if (!opts->pnp_string)
+		goto unlock;
+
+	result = strlcpy(page, opts->pnp_string, PAGE_SIZE);
+	if (result >= PAGE_SIZE) {
+		result = PAGE_SIZE;
+	} else if (page[result - 1] != '\n' && result + 1 < PAGE_SIZE) {
+		page[result++] = '\n';
+		page[result] = '\0';
+	}
+
+unlock:
 	mutex_unlock(&opts->lock);
 
 	return result;
@@ -1170,13 +1186,24 @@ static ssize_t f_printer_opts_pnp_string_store(struct config_item *item,
 					       const char *page, size_t len)
 {
 	struct f_printer_opts *opts = to_f_printer_opts(item);
-	int result, l;
+	char *new_pnp;
+	int result;
 
 	mutex_lock(&opts->lock);
-	result = strlcpy(opts->pnp_string + 2, page, PNP_STRING_LEN - 2);
-	l = strlen(opts->pnp_string + 2) + 2;
-	opts->pnp_string[0] = (l >> 8) & 0xFF;
-	opts->pnp_string[1] = l & 0xFF;
+
+	new_pnp = kstrndup(page, len, GFP_KERNEL);
+	if (!new_pnp) {
+		result = -ENOMEM;
+		goto unlock;
+	}
+
+	if (opts->pnp_string_allocated)
+		kfree(opts->pnp_string);
+
+	opts->pnp_string_allocated = true;
+	opts->pnp_string = new_pnp;
+	result = len;
+unlock:
 	mutex_unlock(&opts->lock);
 
 	return result;
@@ -1270,6 +1297,8 @@ static void gprinter_free_inst(struct usb_function_instance *f)
 
 	mutex_unlock(&printer_ida_lock);
 
+	if (opts->pnp_string_allocated)
+		kfree(opts->pnp_string);
 	kfree(opts);
 }