From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 5C8351772F for ; Mon, 15 May 2023 18:02:35 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id B1FA7C433D2; Mon, 15 May 2023 18:02:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1684173755; bh=sraKeo25oCEdIPlE/2+gjB6EOJuLMCWEpZ8JyLg5YzY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=yKxpKijwhdtEAtDbG7/x2hEWdlDVlYieMuUjrmGhJ6CVFvY9GzQNfGseNLAmBqmST UmGieYPhRSIEobJfMIV+UvVHO2uDUjd1K4wnoorKCybW5o85IkfdnzkQpfz+p6BkB8 8MzCscLzgaMF8S3X7p07EM2aQZdPWkBh74Uagy/0= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Li Nan , Song Liu Subject: [PATCH 5.4 195/282] md/raid10: fix null-ptr-deref in raid10_sync_request Date: Mon, 15 May 2023 18:29:33 +0200 Message-Id: <20230515161728.105334151@linuxfoundation.org> X-Mailer: git-send-email 2.40.1 In-Reply-To: <20230515161722.146344674@linuxfoundation.org> References: <20230515161722.146344674@linuxfoundation.org> User-Agent: quilt/0.67 Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Li Nan commit a405c6f0229526160aa3f177f65e20c86fce84c5 upstream. init_resync() inits mempool and sets conf->have_replacemnt at the beginning of sync, close_sync() frees the mempool when sync is completed. After [1] recovery might be skipped and init_resync() is called but close_sync() is not. null-ptr-deref occurs with r10bio->dev[i].repl_bio. The following is one way to reproduce the issue. 1) create a array, wait for resync to complete, mddev->recovery_cp is set to MaxSector. 2) recovery is woken and it is skipped. conf->have_replacement is set to 0 in init_resync(). close_sync() not called. 3) some io errors and rdev A is set to WantReplacement. 4) a new device is added and set to A's replacement. 5) recovery is woken, A have replacement, but conf->have_replacemnt is 0. r10bio->dev[i].repl_bio will not be alloced and null-ptr-deref occurs. Fix it by not calling init_resync() if recovery skipped. [1] commit 7e83ccbecd60 ("md/raid10: Allow skipping recovery when clean arrays are assembled") Fixes: 7e83ccbecd60 ("md/raid10: Allow skipping recovery when clean arrays are assembled") Cc: stable@vger.kernel.org Signed-off-by: Li Nan Signed-off-by: Song Liu Link: https://lore.kernel.org/r/20230222041000.3341651-3-linan666@huaweicloud.com Signed-off-by: Greg Kroah-Hartman --- drivers/md/raid10.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) --- a/drivers/md/raid10.c +++ b/drivers/md/raid10.c @@ -2920,10 +2920,6 @@ static sector_t raid10_sync_request(stru sector_t chunk_mask = conf->geo.chunk_mask; int page_idx = 0; - if (!mempool_initialized(&conf->r10buf_pool)) - if (init_resync(conf)) - return 0; - /* * Allow skipping a full rebuild for incremental assembly * of a clean array, like RAID1 does. @@ -2939,6 +2935,10 @@ static sector_t raid10_sync_request(stru return mddev->dev_sectors - sector_nr; } + if (!mempool_initialized(&conf->r10buf_pool)) + if (init_resync(conf)) + return 0; + skipped: max_sector = mddev->dev_sectors; if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery) ||