From patchwork Tue Jun 27 08:56:11 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yu Kuai X-Patchwork-Id: 113323 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:a59:994d:0:b0:3d9:f83d:47d9 with SMTP id k13csp8052167vqr; Tue, 27 Jun 2023 02:06:51 -0700 (PDT) X-Google-Smtp-Source: ACHHUZ7EWAROweki4v4UJejOgtZqo4bsB0kMyb3xYXrHkl0Npupzk7OIDVLiBK0Rr+kuk/uCCzzi X-Received: by 2002:a05:6a20:7f9f:b0:12b:93d4:4967 with SMTP id d31-20020a056a207f9f00b0012b93d44967mr489167pzj.26.1687856811232; Tue, 27 Jun 2023 02:06:51 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1687856811; cv=none; d=google.com; s=arc-20160816; b=ksUyk1YnMdJl0KoUwjtnPu3BFd9DGfSGJDtcUCtPvDq8T7CbIKWRic4MxMk4l22d3K 4zWBb2GvMRKGkohghjyWXxF8RXOp6ii/QLoezvID9QLgf/SfAykVeRZFHIxKFPws/BZZ FowhAwGJRO1Hq2wmDxDtrlRMF68+QthuQipkQwXDEyn8ODBO3+qTfwhotBvNa48U+RIh IKFDzJLiX83NlJv+Vd6yeMblBXfIj4Yk5f3loHBsIr09wjq1cB533DFMMmoHW3rN1vLN lQTtQPqHq/G+xCWa/4qTU7DMNJAP1w89Ajm4kkpAFBS/9b1czr8C/Q3Zk89Kcrt7jzbg OGvA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:mime-version :references:in-reply-to:message-id:date:subject:cc:to:from; bh=TxTWG6cUTxajszsRiC0wAT8ioh0XYccvKJJDXqEFl2U=; fh=P2RmqiG/AbPUM/TRpdNI39rrkM+L2D1IF6Cyfyo8sKQ=; b=0suUXD+3MKAb60+UfLpQugURuAYCMvqs5xHts1J/1afbvMTY5EBGjeerFP1OUbeCHE GHylRO5V6McEEsHnamo5C5c2ns7/7BgRRoCIVPKSQBlDZO9rWpGBvVm89VIqu1RsqjcV ohnzd1XipJuYvR6jtAWuWXEUfiJNHxsNrzH9EN9B0eH2Z7YBG8j99ji12X+9Jmr55GIc YelTGYjbYZioReeGnqmndhcwLoiAa/B/h403uQa/Yhw0dI0PywCzVGGtmNkCAl8JEp6m B0y6nbZcT0TeDzHge2Yof83wJFDXVBVdnA3O2tltW6JBRnrUFx3LX20G1KjU/grsGR9F sQbg== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: from out1.vger.email (out1.vger.email. [2620:137:e000::1:20]) by mx.google.com with ESMTP id c3-20020a056a00248300b006600f3102cesi7037140pfv.188.2023.06.27.02.06.39; Tue, 27 Jun 2023 02:06:51 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20; Authentication-Results: mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231307AbjF0I52 (ORCPT + 99 others); Tue, 27 Jun 2023 04:57:28 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53630 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230486AbjF0I5P (ORCPT ); Tue, 27 Jun 2023 04:57:15 -0400 Received: from dggsgout12.his.huawei.com (dggsgout12.his.huawei.com [45.249.212.56]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2A6BE10E2; Tue, 27 Jun 2023 01:57:06 -0700 (PDT) Received: from mail02.huawei.com (unknown [172.30.67.143]) by dggsgout12.his.huawei.com (SkyGuard) with ESMTP id 4Qqz9T0Rq7z4f3yrq; Tue, 27 Jun 2023 16:57:01 +0800 (CST) Received: from huaweicloud.com (unknown [10.175.104.67]) by APP4 (Coremail) with SMTP id gCh0CgAHcLNcpJpkTBKTMg--.3216S6; Tue, 27 Jun 2023 16:57:03 +0800 (CST) From: Yu Kuai To: logang@deltatee.com, hch@lst.de, song@kernel.org, shli@fb.com Cc: linux-raid@vger.kernel.org, linux-kernel@vger.kernel.org, yukuai3@huawei.com, yukuai1@huaweicloud.com, yi.zhang@huawei.com, yangerkun@huawei.com Subject: [PATCH -next 2/2] md/raid5-cache: fix null-ptr-deref in r5l_reclaim_thread() Date: Tue, 27 Jun 2023 16:56:11 +0800 Message-Id: <20230627085611.4186951-3-yukuai1@huaweicloud.com> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230627085611.4186951-1-yukuai1@huaweicloud.com> References: <20230627085611.4186951-1-yukuai1@huaweicloud.com> MIME-Version: 1.0 X-CM-TRANSID: gCh0CgAHcLNcpJpkTBKTMg--.3216S6 X-Coremail-Antispam: 1UD129KBjvJXoWxAr4fuw1rWF4DCrWDKr1xZrb_yoW5ZF17pa 1S93y3Ww48uryfAFnrWr1Dur4F93sF934xG3y5Cwn2yr43Xry8Ja4xCayUAFy5JFW8A3y3 XrW5ta4kWrnrtrJanT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUBE14x267AKxVWrJVCq3wAFc2x0x2IEx4CE42xK8VAvwI8IcIk0 rVWrJVCq3wAFIxvE14AKwVWUJVWUGwA2048vs2IY020E87I2jVAFwI0_Jryl82xGYIkIc2 x26xkF7I0E14v26r4j6ryUM28lY4IEw2IIxxk0rwA2F7IY1VAKz4vEj48ve4kI8wA2z4x0 Y4vE2Ix0cI8IcVAFwI0_Ar0_tr1l84ACjcxK6xIIjxv20xvEc7CjxVAFwI0_Gr1j6F4UJw A2z4x0Y4vEx4A2jsIE14v26rxl6s0DM28EF7xvwVC2z280aVCY1x0267AKxVW0oVCq3wAS 0I0E0xvYzxvE52x082IY62kv0487Mc02F40EFcxC0VAKzVAqx4xG6I80ewAv7VC0I7IYx2 IY67AKxVWUJVWUGwAv7VC2z280aVAFwI0_Jr0_Gr1lOx8S6xCaFVCjc4AY6r1j6r4UM4x0 Y48IcxkI7VAKI48JM4x0x7Aq67IIx4CEVc8vx2IErcIFxwACI402YVCY1x02628vn2kIc2 xKxwCF04k20xvY0x0EwIxGrwCFx2IqxVCFs4IE7xkEbVWUJVW8JwC20s026c02F40E14v2 6r1j6r18MI8I3I0E7480Y4vE14v26r106r1rMI8E67AF67kF1VAFwI0_Jw0_GFylIxkGc2 Ij64vIr41lIxAIcVC0I7IYx2IY67AKxVWUJVWUCwCI42IY6xIIjxv20xvEc7CjxVAFwI0_ Gr0_Cr1lIxAIcVCF04k26cxKx2IYs7xG6r1j6r1xMIIF0xvEx4A2jsIE14v26r1j6r4UMI IF0xvEx4A2jsIEc7CjxVAFwI0_Gr0_Gr1UYxBIdaVFxhVjvjDU0xZFpf9x0JUc6pPUUUUU = X-CM-SenderInfo: 51xn3trlr6x35dzhxuhorxvhhfrp/ X-CFilter-Loop: Reflected X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00,SPF_HELO_NONE, SPF_NONE,T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-getmail-retrieved-from-mailbox: =?utf-8?q?INBOX?= X-GMAIL-THRID: =?utf-8?q?1769846143712362744?= X-GMAIL-MSGID: =?utf-8?q?1769846143712362744?= From: Yu Kuai r5l_reclaim_thread() already check that 'conf->log' is not NULL in the beginning, however, r5c_do_reclaim() and r5c_do_reclaim() will dereference 'conf->log' again, which will cause null-ptr-deref if 'conf->log' is set to NULL from r5l_exit_log() concurrently. Fix this problem by don't dereference 'conf->log' again in r5c_do_reclaim() and r5c_do_reclaim(). Fixes: a39f7afde358 ("md/r5cache: write-out phase and reclaim support") Signed-off-by: Yu Kuai --- drivers/md/raid5-cache.c | 19 ++++++++----------- 1 file changed, 8 insertions(+), 11 deletions(-) diff --git a/drivers/md/raid5-cache.c b/drivers/md/raid5-cache.c index 083288e36949..0cd95d9c3370 100644 --- a/drivers/md/raid5-cache.c +++ b/drivers/md/raid5-cache.c @@ -1148,10 +1148,9 @@ static void r5l_run_no_space_stripes(struct r5l_log *log) * for write through mode, returns log->next_checkpoint * for write back, returns log_start of first sh in stripe_in_journal_list */ -static sector_t r5c_calculate_new_cp(struct r5conf *conf) +static sector_t r5c_calculate_new_cp(struct r5l_log *log) { struct stripe_head *sh; - struct r5l_log *log = conf->log; sector_t new_cp; unsigned long flags; @@ -1159,12 +1158,12 @@ static sector_t r5c_calculate_new_cp(struct r5conf *conf) return log->next_checkpoint; spin_lock_irqsave(&log->stripe_in_journal_lock, flags); - if (list_empty(&conf->log->stripe_in_journal_list)) { + if (list_empty(&log->stripe_in_journal_list)) { /* all stripes flushed */ spin_unlock_irqrestore(&log->stripe_in_journal_lock, flags); return log->next_checkpoint; } - sh = list_first_entry(&conf->log->stripe_in_journal_list, + sh = list_first_entry(&log->stripe_in_journal_list, struct stripe_head, r5c); new_cp = sh->log_start; spin_unlock_irqrestore(&log->stripe_in_journal_lock, flags); @@ -1173,10 +1172,8 @@ static sector_t r5c_calculate_new_cp(struct r5conf *conf) static sector_t r5l_reclaimable_space(struct r5l_log *log) { - struct r5conf *conf = log->rdev->mddev->private; - return r5l_ring_distance(log, log->last_checkpoint, - r5c_calculate_new_cp(conf)); + r5c_calculate_new_cp(log)); } static void r5l_run_no_mem_stripe(struct r5l_log *log) @@ -1419,9 +1416,9 @@ void r5c_flush_cache(struct r5conf *conf, int num) } } -static void r5c_do_reclaim(struct r5conf *conf) +static void r5c_do_reclaim(struct r5l_log *log) { - struct r5l_log *log = conf->log; + struct r5conf *conf = log->rdev->mddev->private; struct stripe_head *sh; int count = 0; unsigned long flags; @@ -1525,7 +1522,7 @@ static void r5l_do_reclaim(struct r5l_log *log) log->io_list_lock); } - next_checkpoint = r5c_calculate_new_cp(conf); + next_checkpoint = r5c_calculate_new_cp(log); spin_unlock_irq(&log->io_list_lock); if (reclaimable == 0 || !write_super) @@ -1554,7 +1551,7 @@ static void r5l_reclaim_thread(struct md_thread *thread) if (!log) return; - r5c_do_reclaim(conf); + r5c_do_reclaim(log); r5l_do_reclaim(log); }