When unloading dependencies make sure they are removed from all the

associated lists:
   remove RTLD_GLOBAL objects from global objects list;
   remove the parent object from dldags list of its children.

Previosly we were doing that only to the top-level object OF the DAG
being unloaded and all its dependencies were ignored, leading to
mysterious crashes later.

Submitted by:	peter (partially)

1 files changed, 10 insertions, 9 deletions

diff --git a/libexec/rtld-elf/rtld.c b/libexec/rtld-elf/rtld.c
index 3ad6017..4408d63 100644
--- a/libexec/rtld-elf/rtld.c
+++ b/libexec/rtld-elf/rtld.c
@@ -2131,17 +2131,9 @@ unload_object(Obj_Entry *root)
 {
     Obj_Entry *obj;
     Obj_Entry **linkp;
-    Objlist_Entry *elm;
 
     assert(root->refcount == 0);
 
-    /* Remove the DAG from all objects' DAG lists. */
-    STAILQ_FOREACH(elm, &root->dagmembers , link)
-	objlist_remove(&elm->obj->dldags, root);
-
-    /* Remove the DAG from the RTLD_GLOBAL list. */
-    objlist_remove(&list_global, root);
-
     /* Unmap all objects that are no longer referenced. */
     linkp = &obj_list->next;
     while ((obj = *linkp) != NULL) {
@@ -2162,14 +2154,23 @@ static void
 unref_dag(Obj_Entry *root)
 {
     const Needed_Entry *needed;
+    Objlist_Entry *elm;
 
     if (root->refcount == 0)
 	return;
     root->refcount--;
-    if (root->refcount == 0)
+    if (root->refcount == 0) {
 	for (needed = root->needed;  needed != NULL;  needed = needed->next)
 	    if (needed->obj != NULL)
 		unref_dag(needed->obj);
+
+	/* Remove the object from the RTLD_GLOBAL list. */
+	objlist_remove(&list_global, root);
+
+    	/* Remove the object from all objects' DAG lists. */
+    	STAILQ_FOREACH(elm, &root->dagmembers , link)
+	    objlist_remove(&elm->obj->dldags, root);
+    }
 }
 
 /*