usbdevfs: Correct amount of data copied to user in processcompl_compat
authorHans de Goede <hdegoede@redhat.com>
Wed, 4 Jul 2012 07:18:01 +0000 (09:18 +0200)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Thu, 9 Aug 2012 15:27:35 +0000 (08:27 -0700)
commit 2102e06a5f2e414694921f23591f072a5ba7db9f upstream.

iso data buffers may have holes in them if some packets were short, so for
iso urbs we should always copy the entire buffer, just like the regular
processcompl does.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/usb/core/devio.c

index ca3c303eed81a70db92fb6b5c2420d9468fa4446..4d1f996b98756eae90172e535967009b1ae24bee 100644 (file)
@@ -1557,10 +1557,14 @@ static int processcompl_compat(struct async *as, void __user * __user *arg)
        void __user *addr = as->userurb;
        unsigned int i;
 
-       if (as->userbuffer && urb->actual_length)
-               if (copy_to_user(as->userbuffer, urb->transfer_buffer,
-                                urb->actual_length))
+       if (as->userbuffer && urb->actual_length) {
+               if (urb->number_of_packets > 0)         /* Isochronous */
+                       i = urb->transfer_buffer_length;
+               else                                    /* Non-Isoc */
+                       i = urb->actual_length;
+               if (copy_to_user(as->userbuffer, urb->transfer_buffer, i))
                        return -EFAULT;
+       }
        if (put_user(as->status, &userurb->status))
                return -EFAULT;
        if (put_user(urb->actual_length, &userurb->actual_length))