patch "usb: misc: legousbtower: Fix buffers on stack" added to usb-next

patch "usb: misc: legousbtower: Fix buffers on stack" added to usb-next

[gregkh]

This is a note to let you know that I've just added the patch titled

    usb: misc: legousbtower: Fix buffers on stack

to my usb git tree which can be found at
    git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git
in the usb-next branch.

The patch will show up in the next release of the linux-next tree
(usually sometime within the next 24 hours during the week.)

The patch will also be merged in the next major kernel release
during the merge window.

If you have any questions about this process, please let me know.


>From 942a48730faf149ccbf3e12ac718aee120bb3529 Mon Sep 17 00:00:00 2001
From: Maksim Salau <maksim.salau@gmail.com>
Date: Tue, 25 Apr 2017 22:49:21 +0300
Subject: usb: misc: legousbtower: Fix buffers on stack

Allocate buffers on HEAP instead of STACK for local structures
that are to be received using usb_control_msg().

Signed-off-by: Maksim Salau <maksim.salau@gmail.com>
Tested-by: Alfredo Rafael Vicente Boix <alviboi@gmail.com>;
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/usb/misc/legousbtower.c | 37 +++++++++++++++++++++++++++----------
 1 file changed, 27 insertions(+), 10 deletions(-)

diff --git a/drivers/usb/misc/legousbtower.c b/drivers/usb/misc/legousbtower.c
index 201c9c3effbb..aa3c280fdf8d 100644
--- a/drivers/usb/misc/legousbtower.c
+++ b/drivers/usb/misc/legousbtower.c
@@ -317,9 +317,16 @@ static int tower_open (struct inode *inode, struct file *file)
 	int subminor;
 	int retval = 0;
 	struct usb_interface *interface;
-	struct tower_reset_reply reset_reply;
+	struct tower_reset_reply *reset_reply;
 	int result;
 
+	reset_reply = kmalloc(sizeof(*reset_reply), GFP_KERNEL);
+
+	if (!reset_reply) {
+		retval = -ENOMEM;
+		goto exit;
+	}
+
 	nonseekable_open(inode, file);
 	subminor = iminor(inode);
 
@@ -364,8 +371,8 @@ static int tower_open (struct inode *inode, struct file *file)
 				  USB_TYPE_VENDOR | USB_DIR_IN | USB_RECIP_DEVICE,
 				  0,
 				  0,
-				  &reset_reply,
-				  sizeof(reset_reply),
+				  reset_reply,
+				  sizeof(*reset_reply),
 				  1000);
 	if (result < 0) {
 		dev_err(&dev->udev->dev,
@@ -406,6 +413,7 @@ static int tower_open (struct inode *inode, struct file *file)
 	mutex_unlock(&dev->lock);
 
 exit:
+	kfree(reset_reply);
 	return retval;
 }
 
@@ -806,7 +814,7 @@ static int tower_probe (struct usb_interface *interface, const struct usb_device
 	struct device *idev = &interface->dev;
 	struct usb_device *udev = interface_to_usbdev(interface);
 	struct lego_usb_tower *dev = NULL;
-	struct tower_get_version_reply get_version_reply;
+	struct tower_get_version_reply *get_version_reply = NULL;
 	int retval = -ENOMEM;
 	int result;
 
@@ -871,6 +879,13 @@ static int tower_probe (struct usb_interface *interface, const struct usb_device
 	dev->interrupt_in_interval = interrupt_in_interval ? interrupt_in_interval : dev->interrupt_in_endpoint->bInterval;
 	dev->interrupt_out_interval = interrupt_out_interval ? interrupt_out_interval : dev->interrupt_out_endpoint->bInterval;
 
+	get_version_reply = kmalloc(sizeof(*get_version_reply), GFP_KERNEL);
+
+	if (!get_version_reply) {
+		retval = -ENOMEM;
+		goto error;
+	}
+
 	/* get the firmware version and log it */
 	result = usb_control_msg (udev,
 				  usb_rcvctrlpipe(udev, 0),
@@ -878,18 +893,19 @@ static int tower_probe (struct usb_interface *interface, const struct usb_device
 				  USB_TYPE_VENDOR | USB_DIR_IN | USB_RECIP_DEVICE,
 				  0,
 				  0,
-				  &get_version_reply,
-				  sizeof(get_version_reply),
+				  get_version_reply,
+				  sizeof(*get_version_reply),
 				  1000);
 	if (result < 0) {
 		dev_err(idev, "LEGO USB Tower get version control request failed\n");
 		retval = result;
 		goto error;
 	}
-	dev_info(&interface->dev, "LEGO USB Tower firmware version is %d.%d "
-		 "build %d\n", get_version_reply.major,
-		 get_version_reply.minor,
-		 le16_to_cpu(get_version_reply.build_no));
+	dev_info(&interface->dev,
+		 "LEGO USB Tower firmware version is %d.%d build %d\n",
+		 get_version_reply->major,
+		 get_version_reply->minor,
+		 le16_to_cpu(get_version_reply->build_no));
 
 	/* we can register the device now, as it is ready */
 	usb_set_intfdata (interface, dev);
@@ -913,6 +929,7 @@ static int tower_probe (struct usb_interface *interface, const struct usb_device
 	return retval;
 
 error:
+	kfree(get_version_reply);
 	tower_delete(dev);
 	return retval;
 }
-- 
2.12.2