usb_endpoint_maxp() returns wMaxPacketSize in its
raw form. Without taking into consideration that it
also contains other bits reserved for isochronous
endpoints.

This patch fixes one occasion where this is a
problem by making sure that we initialize
ep->maxpacket only with lower 10 bits of the value
returned by usb_endpoint_maxp(). Note that seperate
patches will be necessary to audit all call sites of
usb_endpoint_maxp() and make sure that
usb_endpoint_maxp() only returns lower 10 bits of
wMaxPacketSize.

Cc: <sta...@vger.kernel.org>
Signed-off-by: Felipe Balbi <felipe.ba...@linux.intel.com>
---
 drivers/usb/gadget/composite.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/usb/gadget/composite.c b/drivers/usb/gadget/composite.c
index 32176f779861..f6a7583ab6d1 100644
--- a/drivers/usb/gadget/composite.c
+++ b/drivers/usb/gadget/composite.c
@@ -197,7 +197,7 @@ int config_ep_by_speed(struct usb_gadget *g,
 
 ep_found:
        /* commit results */
-       _ep->maxpacket = usb_endpoint_maxp(chosen_desc);
+       _ep->maxpacket = usb_endpoint_maxp(chosen_desc) & 0x7ff;
        _ep->desc = chosen_desc;
        _ep->comp_desc = NULL;
        _ep->maxburst = 0;
-- 
2.10.0.440.g21f862b

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