USB: whci-hcd: check return value of usb_hcd_link_urb_to_ep()

Check the return value of usb_hcd_link_urb_to_ep() and do not add the
urb to the ASL/PZL if it returns an error.

Omitting the check results in urbs that appear to be submitted
successfully but then cannot be unliked (because
usb_hcd_check_unlink_urb() returns an error).  This can cause khubd (for
example) to block forever in usb_kill_urb().

Signed-off-by: David Vrabel <david.vrabel@csr.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

2 files changed, 18 insertions, 6 deletions

diff --git a/drivers/usb/host/whci/asl.c b/drivers/usb/host/whci/asl.c
index be753f664993..c2050785a819 100644
--- a/drivers/usb/host/whci/asl.c
+++ b/drivers/usb/host/whci/asl.c
@@ -255,23 +255,29 @@ int asl_urb_enqueue(struct whc *whc, struct urb *urb, gfp_t mem_flags)
 
         spin_lock_irqsave(&whc->lock, flags);
 
+        err = usb_hcd_link_urb_to_ep(&whc->wusbhc.usb_hcd, urb);
+        if (err < 0) {
+                spin_unlock_irqrestore(&whc->lock, flags);
+                return err;
+        }
+
         qset = get_qset(whc, urb, GFP_ATOMIC);
         if (qset == NULL)
                 err = -ENOMEM;
         else
                 err = qset_add_urb(whc, qset, urb, GFP_ATOMIC);
         if (!err) {
-                usb_hcd_link_urb_to_ep(&whc->wusbhc.usb_hcd, urb);
                 if (!qset->in_sw_list)
                         asl_qset_insert_begin(whc, qset);
-        }
+        } else
+                usb_hcd_unlink_urb_from_ep(&whc->wusbhc.usb_hcd, urb);
 
         spin_unlock_irqrestore(&whc->lock, flags);
 
         if (!err)
                 queue_work(whc->workqueue, &whc->async_work);
 
-        return 0;
+        return err;
 }
 
 /**
diff --git a/drivers/usb/host/whci/pzl.c b/drivers/usb/host/whci/pzl.c
index 0c40022a6b2f..ff4ef9e910d9 100644
--- a/drivers/usb/host/whci/pzl.c
+++ b/drivers/usb/host/whci/pzl.c
@@ -283,23 +283,29 @@ int pzl_urb_enqueue(struct whc *whc, struct urb *urb, gfp_t mem_flags)
 
         spin_lock_irqsave(&whc->lock, flags);
 
+        err = usb_hcd_link_urb_to_ep(&whc->wusbhc.usb_hcd, urb);
+        if (err < 0) {
+                spin_unlock_irqrestore(&whc->lock, flags);
+                return err;
+        }
+
         qset = get_qset(whc, urb, GFP_ATOMIC);
         if (qset == NULL)
                 err = -ENOMEM;
         else
                 err = qset_add_urb(whc, qset, urb, GFP_ATOMIC);
         if (!err) {
-                usb_hcd_link_urb_to_ep(&whc->wusbhc.usb_hcd, urb);
                 if (!qset->in_sw_list)
                         qset_insert_in_sw_list(whc, qset);
-        }
+        } else
+                usb_hcd_unlink_urb_from_ep(&whc->wusbhc.usb_hcd, urb);
 
         spin_unlock_irqrestore(&whc->lock, flags);
 
         if (!err)
                 queue_work(whc->workqueue, &whc->periodic_work);
 
-        return 0;
+        return err;
 }
 
 /**