[PATCH] USB: gadget zero poisons OUT buffers

Fill OUT buffers with 0x55 before RX, so that controller driver
bugs that mangle data can be more readily detected during testing.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/usb/gadget/zero.c b/drivers/usb/gadget/zero.c
index 51424f6..68e3d8f 100644 (file)
--- a/drivers/usb/gadget/zero.c
+++ b/drivers/usb/gadget/zero.c
@@ -572,9 +572,10 @@ static void source_sink_complete (struct usb_ep *ep, struct usb_request *req)
        switch (status) {
 
        case 0:                         /* normal completion? */
-               if (ep == dev->out_ep)
+               if (ep == dev->out_ep) {
                        check_read_data (dev, ep, req);
-               else
+                       memset (req->buf, 0x55, req->length);
+               } else
                        reinit_write_data (dev, ep, req);
                break;
 
@@ -626,6 +627,8 @@ source_sink_start_ep (struct usb_ep *ep, gfp_t gfp_flags)
 
        if (strcmp (ep->name, EP_IN_NAME) == 0)
                reinit_write_data (ep->driver_data, ep, req);
+       else
+               memset (req->buf, 0x55, req->length);
 
        status = usb_ep_queue (ep, req, gfp_flags);
        if (status) {