[PATCH 19/19] RFC: hw/virtio: a potential leak fix

[marcandre . lureau]

From: Marc-André Lureau <marcandre.lureau@redhat.com>

vhost_svq_get_buf() may return a VirtQueueElement that should be freed.

It's unclear to me if the vhost_svq_get_buf() call should always return NULL.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
---
 hw/virtio/vhost-shadow-virtqueue.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/hw/virtio/vhost-shadow-virtqueue.c 
b/hw/virtio/vhost-shadow-virtqueue.c
index cd29cc795b..93742d9ddc 100644
--- a/hw/virtio/vhost-shadow-virtqueue.c
+++ b/hw/virtio/vhost-shadow-virtqueue.c
@@ -414,6 +414,7 @@ static uint16_t vhost_svq_last_desc_of_chain(const 
VhostShadowVirtqueue *svq,
     return i;
 }
 
+G_GNUC_WARN_UNUSED_RESULT
 static VirtQueueElement *vhost_svq_get_buf(VhostShadowVirtqueue *svq,
                                            uint32_t *len)
 {
@@ -529,6 +530,7 @@ size_t vhost_svq_poll(VhostShadowVirtqueue *svq, size_t num)
     uint32_t r = 0;
 
     while (num--) {
+        g_autofree VirtQueueElement *elem = NULL;
         int64_t start_us = g_get_monotonic_time();
 
         do {
@@ -541,7 +543,7 @@ size_t vhost_svq_poll(VhostShadowVirtqueue *svq, size_t num)
             }
         } while (true);
 
-        vhost_svq_get_buf(svq, &r);
+        elem = vhost_svq_get_buf(svq, &r);
         len += r;
     }
 
-- 
2.44.0