usbdevfs: Correct amount of data copied to user in processcompl_compat

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>
CC: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 7 insertions, 3 deletions

diff --git a/drivers/usb/core/devio.c b/drivers/usb/core/devio.c
index e0f107948eba..62679bc031fb 100644
--- a/drivers/usb/core/devio.c
+++ b/drivers/usb/core/devio.c
@@ -1604,10 +1604,14 @@ 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))