From patchwork Mon Oct 10 02:38:58 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kemeng Shi X-Patchwork-Id: 13002226 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 059D6C433F5 for ; Mon, 10 Oct 2022 02:39:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230497AbiJJCjI (ORCPT ); Sun, 9 Oct 2022 22:39:08 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49472 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230202AbiJJCjH (ORCPT ); Sun, 9 Oct 2022 22:39:07 -0400 Received: from szxga02-in.huawei.com (szxga02-in.huawei.com [45.249.212.188]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 800014A82F; Sun, 9 Oct 2022 19:39:05 -0700 (PDT) Received: from kwepemi500016.china.huawei.com (unknown [172.30.72.55]) by szxga02-in.huawei.com (SkyGuard) with ESMTP id 4Mm2zf0m1jzHv7N; Mon, 10 Oct 2022 10:34:06 +0800 (CST) Received: from huawei.com (10.174.178.129) by kwepemi500016.china.huawei.com (7.221.188.220) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.31; Mon, 10 Oct 2022 10:39:03 +0800 From: Kemeng Shi To: , CC: , , , Subject: [PATCH 3/4] blk-cgroup: Add NULL check of pd_alloc_fn in blkcg_activate_policy Date: Mon, 10 Oct 2022 10:38:58 +0800 Message-ID: <20221010023859.11896-4-shikemeng@huawei.com> X-Mailer: git-send-email 2.14.1.windows.1 In-Reply-To: <20221010023859.11896-1-shikemeng@huawei.com> References: <20221010023859.11896-1-shikemeng@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.174.178.129] X-ClientProxiedBy: dggems702-chm.china.huawei.com (10.3.19.179) To kwepemi500016.china.huawei.com (7.221.188.220) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org Function blkcg_policy_register only make sure pd_alloc_fn and pd_free_fn in pairs, so pd_alloc_fn could be NULL in registered blkcg_policy. Check NULL before use for pd_alloc_fn in blkcg_activate_policy to avoid protential NULL dereference. Signed-off-by: Kemeng Shi --- block/blk-cgroup.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c index 463c568d3e86..fc083c35dc42 100644 --- a/block/blk-cgroup.c +++ b/block/blk-cgroup.c @@ -1404,6 +1404,9 @@ int blkcg_activate_policy(struct request_queue *q, if (blkcg_policy_enabled(q, pol)) return 0; + if (pol->pd_alloc_fn == NULL) + return -EINVAL; + if (queue_is_mq(q)) blk_mq_freeze_queue(q); retry: