From patchwork Sun Oct 28 16:07:26 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Geert Uytterhoeven X-Patchwork-Id: 10658673 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 43CB514DE for ; Sun, 28 Oct 2018 16:07:40 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 325BF28C9A for ; Sun, 28 Oct 2018 16:07:40 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 25AE928E7D; Sun, 28 Oct 2018 16:07:40 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id BCFEB28D2D for ; Sun, 28 Oct 2018 16:07:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727671AbeJ2Awi (ORCPT ); Sun, 28 Oct 2018 20:52:38 -0400 Received: from laurent.telenet-ops.be ([195.130.137.89]:33720 "EHLO laurent.telenet-ops.be" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727686AbeJ2Awi (ORCPT ); Sun, 28 Oct 2018 20:52:38 -0400 Received: from ramsan.of.borg ([84.194.111.163]) by laurent.telenet-ops.be with bizsmtp id t47X1y00L3XaVaC0147Xee; Sun, 28 Oct 2018 17:07:35 +0100 Received: from rox.of.borg ([192.168.97.57]) by ramsan.of.borg with esmtp (Exim 4.86_2) (envelope-from ) id 1gGnb9-0001io-Et; Sun, 28 Oct 2018 17:07:31 +0100 Received: from geert by rox.of.borg with local (Exim 4.90_1) (envelope-from ) id 1gGnb9-0006NB-CM; Sun, 28 Oct 2018 17:07:31 +0100 From: Geert Uytterhoeven To: Matias Bjorling , Keith Busch , Jens Axboe , Christoph Hellwig , Sagi Grimberg Cc: Arnd Bergmann , linux-block@vger.kernel.org, linux-nvme@lists.infradead.org, linux-kernel@vger.kernel.org, Geert Uytterhoeven Subject: [PATCH] lightnvm: Fix uninitialized return value in nvm_get_chunk_meta() Date: Sun, 28 Oct 2018 17:07:26 +0100 Message-Id: <20181028160726.24450-1-geert@linux-m68k.org> X-Mailer: git-send-email 2.17.1 MIME-Version: 1.0 Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP With gcc 4.1: drivers/lightnvm/core.c: In function ‘nvm_get_bb_meta’: drivers/lightnvm/core.c:977: warning: ‘ret’ may be used uninitialized in this function and drivers/nvme/host/lightnvm.c: In function ‘nvme_nvm_get_chk_meta’: drivers/nvme/host/lightnvm.c:580: warning: ‘ret’ may be used uninitialized in this function Indeed, if (for the former) the number of channels or LUNs is zero, or (for both) the passed number of chunks is zero, ret will be returned uninitialized. Fix this by preinitializing ret to zero. Fixes: aff3fb18f957de93 ("lightnvm: move bad block and chunk state logic to core") Fixes: a294c199455187d1 ("lightnvm: implement get log report chunk helpers") Signed-off-by: Geert Uytterhoeven --- I don't know if this can happen in practice, but given this is core functionality that can be called from other files, or even from other modules, I think it's better to be safe than sorry. The latter seems to be a pre-existing issue since v4.17. I didn't notice it before, due to the dependency of NVM on PCI (my gcc 4.1 targets m68k, i.e. no PCI). --- drivers/lightnvm/core.c | 2 +- drivers/nvme/host/lightnvm.c | 3 ++- 2 files changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/lightnvm/core.c b/drivers/lightnvm/core.c index efb976a863d2295a..73ab3cf2686804ba 100644 --- a/drivers/lightnvm/core.c +++ b/drivers/lightnvm/core.c @@ -974,7 +974,7 @@ static int nvm_get_bb_meta(struct nvm_dev *dev, sector_t slba, struct ppa_addr ppa; u8 *blks; int ch, lun, nr_blks; - int ret; + int ret = 0; ppa.ppa = slba; ppa = dev_to_generic_addr(dev, ppa); diff --git a/drivers/nvme/host/lightnvm.c b/drivers/nvme/host/lightnvm.c index a4f3b263cd6c60ee..d64805dc8efbaa02 100644 --- a/drivers/nvme/host/lightnvm.c +++ b/drivers/nvme/host/lightnvm.c @@ -577,7 +577,8 @@ static int nvme_nvm_get_chk_meta(struct nvm_dev *ndev, struct ppa_addr ppa; size_t left = nchks * sizeof(struct nvme_nvm_chk_meta); size_t log_pos, offset, len; - int ret, i, max_len; + int i, max_len; + int ret = 0; /* * limit requests to maximum 256K to avoid issuing arbitrary large