xen-netback: fix memory leaks on XenBus disconnect

Eliminate memory leaks introduced several years ago by cleaning the
queue resources which are allocated on XenBus connection event. Namely, queue
structure array and pages used for IO rings.

Signed-off-by: Igor Druzhinin <igor.druzhinin@citrix.com>
Reviewed-by: Paul Durrant <paul.durrant@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/xen-netback/xenbus.c b/drivers/net/xen-netback/xenbus.c
index 3124eaec942745fe9eb6cd4a49ee8bc633d80e67..34e4af9272eae1adc90c79a257b297352920b02c 100644 (file)
--- a/drivers/net/xen-netback/xenbus.c
+++ b/drivers/net/xen-netback/xenbus.c
@@ -493,11 +493,20 @@ static int backend_create_xenvif(struct backend_info *be)
 static void backend_disconnect(struct backend_info *be)
 {
        if (be->vif) {
+               unsigned int queue_index;
+
                xen_unregister_watchers(be->vif);
 #ifdef CONFIG_DEBUG_FS
                xenvif_debugfs_delif(be->vif);
 #endif /* CONFIG_DEBUG_FS */
                xenvif_disconnect_data(be->vif);
+               for (queue_index = 0; queue_index < be->vif->num_queues; ++queue_index)
+                       xenvif_deinit_queue(&be->vif->queues[queue_index]);
+
+               vfree(be->vif->queues);
+               be->vif->num_queues = 0;
+               be->vif->queues = NULL;
+
                xenvif_disconnect_ctrl(be->vif);
        }
 }
@@ -1034,6 +1043,8 @@ static void connect(struct backend_info *be)
 err:
        if (be->vif->num_queues > 0)
                xenvif_disconnect_data(be->vif); /* Clean up existing queues */
+       for (queue_index = 0; queue_index < be->vif->num_queues; ++queue_index)
+               xenvif_deinit_queue(&be->vif->queues[queue_index]);
        vfree(be->vif->queues);
        be->vif->queues = NULL;
        be->vif->num_queues = 0;