[PATCH] USB: core: WARN if pipe direction != setup packet direction

[Alan Stern <stern@rowland.harvard.edu>]

When a control URB is submitted, the direction indicated by URB's pipe
member is supposed to match the direction indicated by the setup
packet's bRequestType member.  A mismatch could lead to trouble,
depending on which field the host controller drivers use for
determining the actual direction.

This shouldn't ever happen; it would represent a careless bug in a
kernel driver somewhere.  This patch adds a dev_WARN to let people
know about the potential problem.

Suggested-by: "Geoffrey D. Bennett" <g@b4.vu>
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>

---


[as1960]


 drivers/usb/core/urb.c |    3 +++
 1 file changed, 3 insertions(+)

Index: usb-devel/drivers/usb/core/urb.c
===================================================================
--- usb-devel.orig/drivers/usb/core/urb.c
+++ usb-devel/drivers/usb/core/urb.c
@@ -407,6 +407,9 @@ int usb_submit_urb(struct urb *urb, gfp_
 			return -ENOEXEC;
 		is_out = !(setup->bRequestType & USB_DIR_IN) ||
 				!setup->wLength;
+		if (usb_pipeout(urb->pipe) != is_out)
+			dev_WARN(&dev->dev, "BOGUS control dir, pipe %x doesn't match bRequestType %x\n",
+					urb->pipe, setup->bRequestType);
 	} else {
 		is_out = usb_endpoint_dir_out(&ep->desc);
 	}