From: Tom Rix <[email protected]>

clang static analysis flags this error

c67x00-sched.c:489:55: warning: Use of memory after it is freed [unix.Malloc]
        usb_hcd_giveback_urb(c67x00_hcd_to_hcd(c67x00), urb, urbp->status);
                                                             ^~~~~~~~~~~~
Problem happens in this block of code

        c67x00_release_urb(c67x00, urb);
        usb_hcd_unlink_urb_from_ep(c67x00_hcd_to_hcd(c67x00), urb);
        spin_unlock(&c67x00->lock);
        usb_hcd_giveback_urb(c67x00_hcd_to_hcd(c67x00), urb, urbp->status);

In the call to c67x00_release_urb has this freeing of urbp

        urbp = urb->hcpriv;
        urb->hcpriv = NULL;
        list_del(&urbp->hep_node);
        kfree(urbp);

And so urbp is freed before usb_hcd_giveback_urb uses it as its 3rd
parameter.

Since all is required is the status, pass the status directly as is
done in c64x00_urb_dequeue

Fixes: e9b29ffc519b ("USB: add Cypress c67x00 OTG controller HCD driver")

Signed-off-by: Tom Rix <[email protected]>
---
 drivers/usb/c67x00/c67x00-sched.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/usb/c67x00/c67x00-sched.c 
b/drivers/usb/c67x00/c67x00-sched.c
index ef1e4ecaee99..f7f6229082ca 100644
--- a/drivers/usb/c67x00/c67x00-sched.c
+++ b/drivers/usb/c67x00/c67x00-sched.c
@@ -486,7 +486,7 @@ c67x00_giveback_urb(struct c67x00_hcd *c67x00, struct urb 
*urb, int status)
        c67x00_release_urb(c67x00, urb);
        usb_hcd_unlink_urb_from_ep(c67x00_hcd_to_hcd(c67x00), urb);
        spin_unlock(&c67x00->lock);
-       usb_hcd_giveback_urb(c67x00_hcd_to_hcd(c67x00), urb, urbp->status);
+       usb_hcd_giveback_urb(c67x00_hcd_to_hcd(c67x00), urb, status);
        spin_lock(&c67x00->lock);
 }
 
-- 
2.18.1

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