The patch I previously applied from Brian Webb was 2 lines off. Oops.
diff --git a/mount.c b/mount.c
index 58d4369..60509d5 100644
--- a/mount.c
+++ b/mount.c
@@ -440,8 +440,8 @@
 			device = strdup(m->mnt_fsname);
 			directory = strdup(m->mnt_dir);
 			filesystemType = strdup(m->mnt_type);
-			string_flags = strdup(string_flags);
 singlemount:			
+			string_flags = strdup(string_flags);
 			rc = EXIT_SUCCESS;
 #ifdef BB_NFSMOUNT
 			if (strchr(device, ':') != NULL)