[PATCH 1/6] mf: Make session_get_node_object() more robust.

[Zhiyi Zhang]

From: Zhiyi Zhang

It's possible that a state object pointer not in the topology node collection gets passed to
session_get_node_object(). Instead of returning the last node when the object is not found, we
should return a NULL so that the state of the last node is not changed by mistake.
---
 dlls/mf/session.c | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/dlls/mf/session.c b/dlls/mf/session.c
index 555a71dcdf7..8fe3260e9f0 100644
--- a/dlls/mf/session.c
+++ b/dlls/mf/session.c
@@ -2809,15 +2809,20 @@ static HRESULT session_start_clock(struct media_session *session)
 static struct topo_node *session_get_node_object(struct media_session *session, IUnknown *object,
         MF_TOPOLOGY_TYPE node_type)
 {
-    struct topo_node *node = NULL;
+    struct topo_node *node = NULL, *found = NULL;

LIST_FOR_EACH_ENTRY(node, &session->presentation.nodes, struct topo_node, entry)
     {
         if (node->type == node_type && object == node->object.object)
+        {
+            found = node;
             break;
+        }
     }

-    return node;
+    if (!found)
+        WARN("Failed to find object %p.\n", object);
+    return found;
 }

static BOOL session_set_node_object_state(struct media_session *session, IUnknown *object,