Restore NULL checks before calling kfree().

Signed-off-by: Christian Limpach <Christian.Limpach@cl.cam.ac.uk>

linux-2.6-xen-sparse/drivers/xen/blkback/xenbus.c

@@ -48,7 +48,8 @@ static int blkback_remove(struct xenbus_device *dev)
 	unregister_xenbus_watch(&be->backend_watch);
 	if (be->blkif)
 		blkif_put(be->blkif);
-	kfree(be->frontpath);
+	if (be->frontpath)
+		kfree(be->frontpath);
 	kfree(be);
 	return 0;
 }
@@ -254,7 +255,8 @@ static int blkback_probe(struct xenbus_device *dev,
  free_be:
 	if (be->backend_watch.node)
 		unregister_xenbus_watch(&be->backend_watch);
-	kfree(frontend);
+	if (frontend)
+		kfree(frontend);
 	kfree(be);
 	return err;
 }

linux-2.6-xen-sparse/drivers/xen/blkfront/blkfront.c

@@ -608,7 +608,8 @@ static int talk_to_backend(struct xenbus_device *dev,
 	}
 
  out:
-	kfree(backend);
+	if (backend)
+		kfree(backend);
 	return err;
 
  abort_transaction:

linux-2.6-xen-sparse/drivers/xen/blktap/xenbus.c

@@ -52,7 +52,8 @@ static int blkback_remove(struct xenbus_device *dev)
 	unregister_xenbus_watch(&be->backend_watch);
 	if (be->blkif)
 		blkif_put(be->blkif);
-	kfree(be->frontpath);
+	if (be->frontpath)
+		kfree(be->frontpath);
 	kfree(be);
 	return 0;
 }
@@ -199,7 +200,8 @@ static int blkback_probe(struct xenbus_device *dev,
  free_be:
 	if (be->backend_watch.node)
 		unregister_xenbus_watch(&be->backend_watch);
-	kfree(frontend);
+	if (frontend)
+		kfree(frontend);
 	kfree(be);
 	return err;
 }

linux-2.6-xen-sparse/drivers/xen/netback/loopback.c

@@ -160,8 +160,10 @@ static int __init make_loopback(int i)
 	return 0;
 
  fail:
-	kfree(dev1);
-	kfree(dev2);
+	if (dev1 != NULL)
+		kfree(dev1);
+	if (dev2 != NULL)
+		kfree(dev2);
 	return err;
 }
 

linux-2.6-xen-sparse/drivers/xen/netback/xenbus.c

@@ -50,7 +50,8 @@ static int netback_remove(struct xenbus_device *dev)
 	unregister_xenbus_watch(&be->backend_watch);
 	if (be->netif)
 		netif_disconnect(be->netif);
-	kfree(be->frontpath);
+	if (be->frontpath)
+		kfree(be->frontpath);
 	kfree(be);
 	return 0;
 }
@@ -269,7 +270,8 @@ static int netback_probe(struct xenbus_device *dev,
  free_be:
 	if (be->backend_watch.node)
 		unregister_xenbus_watch(&be->backend_watch);
-	kfree(frontend);
+	if (frontend)
+		kfree(frontend);
 	kfree(be);
 	return err;
 }

linux-2.6-xen-sparse/drivers/xen/netfront/netfront.c

@@ -1232,7 +1232,8 @@ static int talk_to_backend(struct xenbus_device *dev,
 	netif_state = NETIF_STATE_CONNECTED;
 
  out:
-	kfree(backend);
+	if (backend)
+		kfree(backend);
 	return err;
 
  abort_transaction:

linux-2.6-xen-sparse/drivers/xen/tpmback/tpmback.c

@@ -148,7 +148,9 @@ static void inline
 packet_free(struct packet *pak)
 {
 	del_singleshot_timer_sync(&pak->processing_timer);
-	kfree(pak->data_buffer);
+	if (pak->data_buffer) {
+		kfree(pak->data_buffer);
+	}
 	/*
 	 * cannot do tpmif_put(pak->tpmif); bad things happen
 	 * on the last tpmif_put()

linux-2.6-xen-sparse/drivers/xen/tpmback/xenbus.c

@@ -52,7 +52,8 @@ static int tpmback_remove(struct xenbus_device *dev)
 		tpmif_put(be->tpmif);
 	}
 
-	kfree(be->frontpath);
+	if (be->frontpath)
+		kfree(be->frontpath);
 	kfree(be);
 	return 0;
 }
@@ -242,7 +243,8 @@ static int tpmback_probe(struct xenbus_device *dev,
 free_be:
 	if (be->backend_watch.node)
 		unregister_xenbus_watch(&be->backend_watch);
-	kfree(frontend);
+	if (frontend)
+		kfree(frontend);
 	kfree(be);
 	return err;
 }

linux-2.6-xen-sparse/drivers/xen/tpmfront/tpmfront.c

@@ -363,7 +363,8 @@ static int talk_to_backend(struct xenbus_device *dev,
 	}
 
 out:
-	kfree(backend);
+	if (backend)
+		kfree(backend);
 	return err;
 
 abort_transaction:

linux-2.6-xen-sparse/drivers/xen/usbback/usbback.c

@@ -781,7 +781,8 @@ static void dispatch_usb_io(usbif_priv_t *up, usbif_request_t *req)
     return;
     
  no_mem:
-    kfree(setup);
+    if ( setup != NULL )
+        kfree(setup);
     make_response(up, req->id, req->operation, -ENOMEM, 0, 0);
     return;
 } 

linux-2.6-xen-sparse/drivers/xen/usbfront/usbfront.c

@@ -1720,7 +1720,8 @@ static int __init xhci_hcd_init(void)
 	return 0;
 
 up_failed:
-	kfree(errbuf);
+	if (errbuf)
+		kfree(errbuf);
 
 errbuf_failed:
 	return retval;