diff --git a/builtin/fsck.c b/builtin/fsck.c
index f7916f06ed..41acbc229e 100644
--- a/builtin/fsck.c
+++ b/builtin/fsck.c
@@ -228,6 +228,8 @@ static void mark_unreachable_referents(const struct object_id *oid)
 
 	options.walk = mark_used;
 	fsck_walk(obj, NULL, &options);
+	if (obj->type == OBJ_TREE)
+		free_tree_buffer((struct tree *)obj);
 }
 
 static int mark_loose_unreachable_referents(const struct object_id *oid,
@@ -437,9 +439,6 @@ static int fsck_obj(struct object *obj, void *buffer, unsigned long size)
 out:
 	if (obj->type == OBJ_TREE)
 		free_tree_buffer((struct tree *)obj);
-	if (obj->type == OBJ_COMMIT)
-		free_commit_buffer(the_repository->parsed_objects,
-				   (struct commit *)obj);
 	return err;
 }
 
@@ -853,6 +852,7 @@ int cmd_fsck(int argc, const char **argv, const char *prefix)
 
 	errors_found = 0;
 	read_replace_refs = 0;
+	save_commit_buffer = 0;
 
 	argc = parse_options(argc, argv, prefix, fsck_opts, fsck_usage, 0);
 
diff --git a/object.c b/object.c
index 2e4589bae5..8a74eb85e9 100644
--- a/object.c
+++ b/object.c
@@ -233,7 +233,8 @@ struct object *parse_object_buffer(struct repository *r, const struct object_id
 		if (commit) {
 			if (parse_commit_buffer(r, commit, buffer, size, 1))
 				return NULL;
-			if (!get_cached_commit_buffer(r, commit, NULL)) {
+			if (save_commit_buffer &&
+			    !get_cached_commit_buffer(r, commit, NULL)) {
 				set_commit_buffer(r, commit, buffer, size);
 				*eaten_p = 1;
 			}