From patchwork Fri May 26 07:45:48 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Li Nan X-Patchwork-Id: 13256567 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 740DFC7EE2F for ; Fri, 26 May 2023 07:47:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S242347AbjEZHrr (ORCPT ); Fri, 26 May 2023 03:47:47 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42446 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236059AbjEZHrj (ORCPT ); Fri, 26 May 2023 03:47:39 -0400 Received: from dggsgout11.his.huawei.com (dggsgout11.his.huawei.com [45.249.212.51]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2B45512C; Fri, 26 May 2023 00:47:36 -0700 (PDT) Received: from mail02.huawei.com (unknown [172.30.67.153]) by dggsgout11.his.huawei.com (SkyGuard) with ESMTP id 4QSH842JXdz4f41Vk; Fri, 26 May 2023 15:47:32 +0800 (CST) Received: from huaweicloud.com (unknown [10.175.127.227]) by APP4 (Coremail) with SMTP id gCh0CgCX_7INZHBko+n3KA--.7888S5; Fri, 26 May 2023 15:47:33 +0800 (CST) From: linan666@huaweicloud.com To: song@kernel.org, bingjingc@synology.com, allenpeng@synology.com, alexwu@synology.com, shli@fb.com, neilb@suse.de Cc: linux-raid@vger.kernel.org, linux-kernel@vger.kernel.org, linan122@huawei.com, yukuai3@huawei.com, yi.zhang@huawei.com, houtao1@huawei.com, yangerkun@huawei.com Subject: [PATCH v2 1/4] md/raid10: fix null-ptr-deref of mreplace in raid10_sync_request Date: Fri, 26 May 2023 15:45:48 +0800 Message-Id: <20230526074551.669792-2-linan666@huaweicloud.com> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20230526074551.669792-1-linan666@huaweicloud.com> References: <20230526074551.669792-1-linan666@huaweicloud.com> MIME-Version: 1.0 X-CM-TRANSID: gCh0CgCX_7INZHBko+n3KA--.7888S5 X-Coremail-Antispam: 1UD129KBjvJXoW7Kw47KrWDCF4UGry7Wr43GFg_yoW8trWfp3 y7tF9rGw4UG3yjka1DA3ZrWF1SvasrJrW5Cry5W343Zr1agrZrCay8WFWYvFyDXF4Yg3yY qw1jyws8uFWxXa7anT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUmjb4IE77IF4wAFF20E14v26rWj6s0DM7CY07I20VC2zVCF04k2 6cxKx2IYs7xG6rWj6s0DM7CIcVAFz4kK6r1j6r18M28IrcIa0xkI8VA2jI8067AKxVWUGw A2048vs2IY020Ec7CjxVAFwI0_Gr0_Xr1l8cAvFVAK0II2c7xJM28CjxkF64kEwVA0rcxS w2x7M28EF7xvwVC0I7IYx2IY67AKxVWDJVCq3wA2z4x0Y4vE2Ix0cI8IcVCY1x0267AKxV W8Jr0_Cr1UM28EF7xvwVC2z280aVAFwI0_GcCE3s1l84ACjcxK6I8E87Iv6xkF7I0E14v2 6rxl6s0DM2vYz4IE04k24VAvwVAKI4IrM2AIxVAIcxkEcVAq07x20xvEncxIr21l5I8CrV ACY4xI64kE6c02F40Ex7xfMcIj6xIIjxv20xvE14v26r126r1DMcIj6I8E87Iv67AKxVWU JVW8JwAm72CE4IkC6x0Yz7v_Jr0_Gr1lF7xvr2IYc2Ij64vIr41lFIxGxcIEc7CjxVA2Y2 ka0xkIwI1lw4CEc2x0rVAKj4xxMxAIw28IcxkI7VAKI48JMxC20s026xCaFVCjc4AY6r1j 6r4UMI8I3I0E5I8CrVAFwI0_Jr0_Jr4lx2IqxVCjr7xvwVAFwI0_JrI_JrWlx4CE17CEb7 AF67AKxVWUtVW8ZwCIc40Y0x0EwIxGrwCI42IY6xIIjxv20xvE14v26r1j6r1xMIIF0xvE 2Ix0cI8IcVCY1x0267AKxVW8JVWxJwCI42IY6xAIw20EY4v20xvaj40_Jr0_JF4lIxAIcV C2z280aVAFwI0_Jr0_Gr1lIxAIcVC2z280aVCY1x0267AKxVW8JVW8JrUvcSsGvfC2Kfnx nUUI43ZEXa7IU8qg43UUUUU== X-CM-SenderInfo: polqt0awwwqx5xdzvxpfor3voofrz/ X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-raid@vger.kernel.org From: Li Nan need_replace will be set to 1 if no-Faulty mreplace exists, and mreplace will be deref later. However, the latter check of mreplace might set mreplace to NULL, null-ptr-deref occurs if need_replace is 1 at this time. Fix it by merging two checks into one. And replace 'need_replace' with 'mreplace' because their values are always the same. Fixes: ee37d7314a32 ("md/raid10: Fix raid10 replace hang when new added disk faulty") Signed-off-by: Li Nan Reviewed-by: Yu Kuai --- drivers/md/raid10.c | 13 +++++-------- 1 file changed, 5 insertions(+), 8 deletions(-) diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c index 4fcfcb350d2b..e21502c03b45 100644 --- a/drivers/md/raid10.c +++ b/drivers/md/raid10.c @@ -3438,7 +3438,6 @@ static sector_t raid10_sync_request(struct mddev *mddev, sector_t sector_nr, int must_sync; int any_working; int need_recover = 0; - int need_replace = 0; struct raid10_info *mirror = &conf->mirrors[i]; struct md_rdev *mrdev, *mreplace; @@ -3451,10 +3450,10 @@ static sector_t raid10_sync_request(struct mddev *mddev, sector_t sector_nr, !test_bit(In_sync, &mrdev->flags)) need_recover = 1; if (mreplace != NULL && - !test_bit(Faulty, &mreplace->flags)) - need_replace = 1; + test_bit(Faulty, &mreplace->flags)) + mreplace = NULL; - if (!need_recover && !need_replace) { + if (!need_recover && !mreplace) { rcu_read_unlock(); continue; } @@ -3470,8 +3469,6 @@ static sector_t raid10_sync_request(struct mddev *mddev, sector_t sector_nr, rcu_read_unlock(); continue; } - if (mreplace && test_bit(Faulty, &mreplace->flags)) - mreplace = NULL; /* Unless we are doing a full sync, or a replacement * we only need to recover the block if it is set in * the bitmap @@ -3594,11 +3591,11 @@ static sector_t raid10_sync_request(struct mddev *mddev, sector_t sector_nr, bio = r10_bio->devs[1].repl_bio; if (bio) bio->bi_end_io = NULL; - /* Note: if need_replace, then bio + /* Note: if replace is not NULL, then bio * cannot be NULL as r10buf_pool_alloc will * have allocated it. */ - if (!need_replace) + if (!mreplace) break; bio->bi_next = biolist; biolist = bio;