From mboxrd@z Thu Jan 1 00:00:00 1970 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=-18.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=unavailable 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 29AD8C43333 for ; Mon, 4 Jan 2021 16:02:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id F2F9022518 for ; Mon, 4 Jan 2021 16:02:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728855AbhADQC3 (ORCPT ); Mon, 4 Jan 2021 11:02:29 -0500 Received: from mail.kernel.org ([198.145.29.99]:39414 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728817AbhADQC1 (ORCPT ); Mon, 4 Jan 2021 11:02:27 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 35A15207AE; Mon, 4 Jan 2021 16:02:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1609776131; bh=AXtDkQKhoWWnD9n01X/y6OhukaBW29RrVkYKZcKQVec=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ZAkcQR9zGxf55qRsuQDcD78jMM21FYe7GgBRP+SeoGfnX9iVXaKqz0RFFvd2mCEn7 WNG7CwA0Yg6aUmy1PmQvADcQbrZ9lTlX6cvHgW0ICJk5LsVuoHjcf/Mbn8mr5xgMtr qdWZvaGQx2nt7+3CeWKrSjKyox4ns8FWr/3lEshA= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Kevin Vigor , Song Liu Subject: [PATCH 5.10 05/63] md/raid10: initialize r10_bio->read_slot before use. Date: Mon, 4 Jan 2021 16:56:58 +0100 Message-Id: <20210104155709.068169358@linuxfoundation.org> X-Mailer: git-send-email 2.30.0 In-Reply-To: <20210104155708.800470590@linuxfoundation.org> References: <20210104155708.800470590@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Kevin Vigor commit 93decc563637c4288380912eac0eb42fb246cc04 upstream. In __make_request() a new r10bio is allocated and passed to raid10_read_request(). The read_slot member of the bio is not initialized, and the raid10_read_request() uses it to index an array. This leads to occasional panics. Fix by initializing the field to invalid value and checking for valid value in raid10_read_request(). Cc: stable@vger.kernel.org Signed-off-by: Kevin Vigor Signed-off-by: Song Liu Signed-off-by: Greg Kroah-Hartman --- drivers/md/raid10.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/drivers/md/raid10.c +++ b/drivers/md/raid10.c @@ -1128,7 +1128,7 @@ static void raid10_read_request(struct m struct md_rdev *err_rdev = NULL; gfp_t gfp = GFP_NOIO; - if (r10_bio->devs[slot].rdev) { + if (slot >= 0 && r10_bio->devs[slot].rdev) { /* * This is an error retry, but we cannot * safely dereference the rdev in the r10_bio, @@ -1493,6 +1493,7 @@ static void __make_request(struct mddev r10_bio->mddev = mddev; r10_bio->sector = bio->bi_iter.bi_sector; r10_bio->state = 0; + r10_bio->read_slot = -1; memset(r10_bio->devs, 0, sizeof(r10_bio->devs[0]) * conf->copies); if (bio_data_dir(bio) == READ)