diff --git a/lrzip.c b/lrzip.c
index 69fec18..579219a 100644
--- a/lrzip.c
+++ b/lrzip.c
@@ -702,6 +702,21 @@ static void release_hashes(rzip_control *control)
 	dealloc(control->hash);
 }
 
+static void clear_rulist(rzip_control *control)
+{
+	while (control->ruhead) {
+		struct runzip_node *node = control->ruhead;
+		struct stream_info *sinfo = node->sinfo;
+
+		dealloc(sinfo->ucthreads);
+		dealloc(node->pthreads);
+		dealloc(sinfo->s);
+		dealloc(sinfo);
+		control->ruhead = node->prev;
+		dealloc(node);
+	}
+}
+
 /*
   decompress one file from the command line
 */
diff --git a/lrzip_private.h b/lrzip_private.h
index 8296e86..0e853f7 100644
--- a/lrzip_private.h
+++ b/lrzip_private.h
@@ -470,7 +470,6 @@ struct rzip_control {
 	i64 (*match_len)(rzip_control *, struct rzip_state *, i64, i64, i64, i64 *);
 
 	pthread_t *pthreads;
-	struct runzip_node *rulist;
 	struct runzip_node *ruhead;
 };
 
diff --git a/runzip.c b/runzip.c
index 36ecee9..e3a04b2 100644
--- a/runzip.c
+++ b/runzip.c
@@ -249,21 +249,6 @@ static i64 unzip_match(rzip_control *control, void *ss, i64 len, uint32 *cksum,
 	return total;
 }
 
-void clear_rulist(rzip_control *control)
-{
-	while (control->ruhead) {
-		struct runzip_node *node = control->ruhead;
-		struct stream_info *sinfo = node->sinfo;
-
-		dealloc(sinfo->ucthreads);
-		dealloc(node->pthreads);
-		dealloc(sinfo->s);
-		dealloc(sinfo);
-		control->ruhead = node->prev;
-		dealloc(node);
-	}
-}
-
 /* decompress a section of an open file. Call fatal_return(() on error
    return the number of bytes that have been retrieved
  */
diff --git a/runzip.h b/runzip.h
index a275bd3..9f7826b 100644
--- a/runzip.h
+++ b/runzip.h
@@ -22,7 +22,6 @@
 
 #include "lrzip_private.h"
 
-void clear_rulist(rzip_control *control);
 i64 runzip_fd(rzip_control *control, int fd_in, int fd_hist, i64 expected_size);
 
 #endif
diff --git a/stream.c b/stream.c
index 1215b9e..eaaa425 100644
--- a/stream.c
+++ b/stream.c
@@ -1853,8 +1853,11 @@ static void add_to_rulist(rzip_control *control, struct stream_info *sinfo)
 		failure("Failed to calloc struct node in add_rulist\n");
 	node->sinfo = sinfo;
 	node->pthreads = control->pthreads;
-	node->prev = control->rulist;
+
+	lock_mutex(control, &control->control_lock);
+	node->prev = control->ruhead;
 	control->ruhead = node;
+	unlock_mutex(control, &control->control_lock);
 }
 
 /* close down an input stream */