fix get_active_super()/umount() race (1494583d) · Commits · jan.koester / Linux

fs/super.c

+7 −7

Original line number	Original line	Diff line number	Diff line
	@@ -471,17 +471,17 @@ struct super_block get_active_super(struct block_device bdev)
	if (!bdev)		if (!bdev)
	return NULL;		return NULL;

			restart:
	spin_lock(&sb_lock);		spin_lock(&sb_lock);
	list_for_each_entry(sb, &super_blocks, s_list) {		list_for_each_entry(sb, &super_blocks, s_list) {
	if (list_empty(&sb->s_instances))		if (list_empty(&sb->s_instances))
	continue;		continue;
	if (sb->s_bdev != bdev)		if (sb->s_bdev == bdev) {
	continue;

	if (grab_super(sb)) /* drops sb_lock */		if (grab_super(sb)) /* drops sb_lock */
	return sb;		return sb;
			else
	spin_lock(&sb_lock);		goto restart;
			}
	}		}
	spin_unlock(&sb_lock);		spin_unlock(&sb_lock);
	return NULL;		return NULL;