usb: ci_udc: fix request allocation when endpoints are disabled

The ci_udc driver request allocation assumes that the endpoint descriptor
pointer is set to retrieve the endpoint number, but that is only true
when the endpoint is enabled. This results in a NULL ptr dereference
which for me happens to return 0 value. This causes the EP0 request
struct to be returned for other endpoints. Some gadget drivers like
fastboot and USB MS work fine, but ethernet does not.

Really, the ci_udc driver is the oddball here doing this EP0 special
case handling Stephen added. All the other drivers alloc/free functions
are pretty much the same with the only variation being the size of the
private struct. This could all be consolidated to a common function.

Signed-off-by: Rob Herring <robh@kernel.org>
Cc: Marek Vasut <marex@denx.de>
Acked-by: Stephen Warren <swarren@nvidia.com>

1 files changed, 8 insertions, 4 deletions

diff --git a/drivers/usb/gadget/ci_udc.c b/drivers/usb/gadget/ci_udc.c
index 993be315a8..3e8eb8799f 100644
--- a/drivers/usb/gadget/ci_udc.c
+++ b/drivers/usb/gadget/ci_udc.c
@@ -258,10 +258,12 @@ static struct usb_request *
 ci_ep_alloc_request(struct usb_ep *ep, unsigned int gfp_flags)
 {
 	struct ci_ep *ci_ep = container_of(ep, struct ci_ep, ep);
-	int num;
+	int num = -1;
 	struct ci_req *ci_req;
 
-	num = ci_ep->desc->bEndpointAddress & USB_ENDPOINT_NUMBER_MASK;
+	if (ci_ep->desc)
+		num = ci_ep->desc->bEndpointAddress & USB_ENDPOINT_NUMBER_MASK;
+
 	if (num == 0 && controller.ep0_req)
 		return &controller.ep0_req->req;
 
@@ -281,9 +283,11 @@ static void ci_ep_free_request(struct usb_ep *ep, struct usb_request *req)
 {
 	struct ci_ep *ci_ep = container_of(ep, struct ci_ep, ep);
 	struct ci_req *ci_req = container_of(req, struct ci_req, req);
-	int num;
+	int num = -1;
+
+	if (ci_ep->desc)
+		num = ci_ep->desc->bEndpointAddress & USB_ENDPOINT_NUMBER_MASK;
 
-	num = ci_ep->desc->bEndpointAddress & USB_ENDPOINT_NUMBER_MASK;
 	if (num == 0) {
 		if (!controller.ep0_req)
 			return;