diff --git a/libmpcodecs/pullup.c b/libmpcodecs/pullup.c
index 006934fc6f..04f2106572 100644
--- a/libmpcodecs/pullup.c
+++ b/libmpcodecs/pullup.c
@@ -795,6 +795,7 @@ void pullup_free_context(struct pullup_context *c)
 	free(c->buffers);
 	f = c->head;
 	do {
+		if (!f) break;
 		free(f->diffs);
 		free(f->comb);
 		f = f->next;