[34-longterm 030/179] usb: gadget: rndis: don't test against req->length

From: Paul Gortmaker
Date: Mon May 14 2012 - 22:17:46 EST

From: Felipe Balbi <balbi@xxxxxx>

This is a commit scheduled for the next v2.6.34 longterm release.
If you see a problem with using this for longterm, please comment.

commit 472b91274a6c6857877b5caddb875dcb5ecdfcb8 upstream.

composite.c always sets req->length to zero
and expects function driver's setup handlers
to return the amount of bytes to be used
on req->length. If we test against req->length
w_length will always be greater than req->length
thus making us always stall that particular

Tested against a Windows XP SP3.

Signed-off-by: Felipe Balbi <balbi@xxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxx>
Signed-off-by: Paul Gortmaker <paul.gortmaker@xxxxxxxxxxxxx>
drivers/usb/gadget/f_rndis.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/usb/gadget/f_rndis.c b/drivers/usb/gadget/f_rndis.c
index 56b0221..d1eb94a 100644
--- a/drivers/usb/gadget/f_rndis.c
+++ b/drivers/usb/gadget/f_rndis.c
@@ -420,8 +420,7 @@ rndis_setup(struct usb_function *f, const struct usb_ctrlrequest *ctrl)
- if (w_length > req->length || w_value
- || w_index != rndis->ctrl_id)
+ if (w_value || w_index != rndis->ctrl_id)
goto invalid;
/* read the request; process it later */
value = w_length;

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