From patchwork Sun Aug 8 03:17:51 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yu Kuai X-Patchwork-Id: 12424649 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6F063C4320A for ; Sun, 8 Aug 2021 03:07:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 41C5360EE8 for ; Sun, 8 Aug 2021 03:07:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230139AbhHHDHd (ORCPT ); Sat, 7 Aug 2021 23:07:33 -0400 Received: from szxga01-in.huawei.com ([45.249.212.187]:7808 "EHLO szxga01-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229882AbhHHDHb (ORCPT ); Sat, 7 Aug 2021 23:07:31 -0400 Received: from dggemv704-chm.china.huawei.com (unknown [172.30.72.54]) by szxga01-in.huawei.com (SkyGuard) with ESMTP id 4Gj3z645vvzYlWZ; Sun, 8 Aug 2021 11:06:58 +0800 (CST) Received: from dggema762-chm.china.huawei.com (10.1.198.204) by dggemv704-chm.china.huawei.com (10.3.19.47) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256) id 15.1.2176.2; Sun, 8 Aug 2021 11:07:09 +0800 Received: from huawei.com (10.175.127.227) by dggema762-chm.china.huawei.com (10.1.198.204) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.2176.2; Sun, 8 Aug 2021 11:07:08 +0800 From: Yu Kuai To: , , CC: , , , , Subject: [PATCH 1/2] blk-mq: add two interfaces to lock/unlock blk_mq_tags->lock Date: Sun, 8 Aug 2021 11:17:51 +0800 Message-ID: <20210808031752.579882-2-yukuai3@huawei.com> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210808031752.579882-1-yukuai3@huawei.com> References: <20210808031752.579882-1-yukuai3@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.175.127.227] X-ClientProxiedBy: dggems702-chm.china.huawei.com (10.3.19.179) To dggema762-chm.china.huawei.com (10.1.198.204) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org Ming Lei had fixed the request UAF while iterating tags, however some drivers is calling blk_mq_tag_to_rq() directly to get request through tag. So the problem might still exist since that blk_mq_tags->lock should be held. Thus add blk_mq_tags_lock() and blk_mq_tags_unlock() so that drivers can lock and unlock blk_mq_tags->lock if they are not sure that the request is valid. Signed-off-by: Yu Kuai --- block/blk-mq-tag.c | 12 ++++++++++++ include/linux/blk-mq.h | 2 ++ 2 files changed, 14 insertions(+) diff --git a/block/blk-mq-tag.c b/block/blk-mq-tag.c index 86f87346232a..388d447c993a 100644 --- a/block/blk-mq-tag.c +++ b/block/blk-mq-tag.c @@ -652,3 +652,15 @@ u32 blk_mq_unique_tag(struct request *rq) (rq->tag & BLK_MQ_UNIQUE_TAG_MASK); } EXPORT_SYMBOL(blk_mq_unique_tag); + +void blk_mq_tags_lock(struct blk_mq_tags *tags, unsigned long *flags) +{ + spin_lock_irqsave(&tags->lock, *flags); +} +EXPORT_SYMBOL(blk_mq_tags_lock); + +void blk_mq_tags_unlock(struct blk_mq_tags *tags, unsigned long *flags) +{ + spin_unlock_irqrestore(&tags->lock, *flags); +} +EXPORT_SYMBOL(blk_mq_tags_unlock); diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h index 1d18447ebebc..b4bad4d6a3a8 100644 --- a/include/linux/blk-mq.h +++ b/include/linux/blk-mq.h @@ -635,4 +635,6 @@ blk_qc_t blk_mq_submit_bio(struct bio *bio); void blk_mq_hctx_set_fq_lock_class(struct blk_mq_hw_ctx *hctx, struct lock_class_key *key); +void blk_mq_tags_lock(struct blk_mq_tags *tags, unsigned long *flags); +void blk_mq_tags_unlock(struct blk_mq_tags *tags, unsigned long *flags); #endif