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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 385C2C4332F for ; Mon, 28 Mar 2022 07:56:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239004AbiC1H6T (ORCPT ); Mon, 28 Mar 2022 03:58:19 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42742 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239000AbiC1H6Q (ORCPT ); Mon, 28 Mar 2022 03:58:16 -0400 Received: from mail-pl1-x62d.google.com (mail-pl1-x62d.google.com [IPv6:2607:f8b0:4864:20::62d]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 845A7DFAC; Mon, 28 Mar 2022 00:56:36 -0700 (PDT) Received: by mail-pl1-x62d.google.com with SMTP id n18so14095942plg.5; Mon, 28 Mar 2022 00:56:36 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=kIfOoBDYEc7M5gSagMNoiVBJWuRqusDCDKPYz/4md+8=; b=VqmjjWWVXkOeUbp3XOSMawZfyabaCITsH95uynydk7I4N2p27oAZ8BomdJ9dUuAg8O yUuHzJB8t+LlX0UyIBbQbUH8PnsHWklT95BiTFlk5WNeysGT31aaCPf6RPx6RY0xR+4y rzS9CwsJbvzu8lq7h2rvET9O5YuQBPrr1i0xZ0BKAVacjSeNxuvgjSKMO3pBGLps4gBq v5hq97ZVruMim+482HeCJuUAgAcQkpE0Y/4NcLWdw8ZM6irZrCx7AqsSgpJEtyPnZO1J YVeJfWH8enKrAWk8lIDcFhuT4r5xM+JcD9KDQt+qIzbe1ik9XeGUuWw5+1PVX3dftMSw foAw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=kIfOoBDYEc7M5gSagMNoiVBJWuRqusDCDKPYz/4md+8=; b=7mvnNOVHD+VqM2FKTvu98fXtkeww6J0lyTQx/1aJEQjU95omfRDSZnlsoxRpGvMMSS tHz0exTnIa6unKIReqq9byifGrr2l2DXiOUY48HMrfdzSXqh9vKNmFQ9ZuOtzx0qYf2e Sl33CqrrsIJnSaM5r8aM0YOkCxSqcYjzuwam+j4LszxlQ7+klOkBrzd/Rh2EkwyJ2Onu Mp7p1ZI6JzWjplIKs4LGW3npkXzkiyUuymwpgD8mzBsp9rmKtNDPDAn+hLFPG0a0a+1h IN0o95CIcQp7JBFCylkw9/Vv8tiZ3kbV4Mh/vQh3eLl5wDe3slOsTYrE5RSTAPgjTonk rWOA== X-Gm-Message-State: AOAM532vVOYo3a9lRLlrJsxEoUAv8QlwS/MW01ZPzgJkO64LP5wtty1Y fxpjNo3XpjRnDjYBpnTynVDX4qdjeCtBdw== X-Google-Smtp-Source: ABdhPJwcYDZozrvxZwaqZGIKEnQhsqa0JD+d94ZjOS77DvW2lF4Y4Lkxl8Y03SezxTarAov7sSReFA== X-Received: by 2002:a17:90a:de82:b0:1c7:b10f:e33f with SMTP id n2-20020a17090ade8200b001c7b10fe33fmr26704591pjv.204.1648454196113; Mon, 28 Mar 2022 00:56:36 -0700 (PDT) Received: from ubuntu.huawei.com ([119.3.119.18]) by smtp.googlemail.com with ESMTPSA id v13-20020a17090a088d00b001c64d30fa8bsm16354494pjc.1.2022.03.28.00.56.32 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 28 Mar 2022 00:56:35 -0700 (PDT) From: Xiaomeng Tong To: guoqing.jiang@linux.dev Cc: linux-kernel@vger.kernel.org, linux-raid@vger.kernel.org, rgoldwyn@suse.com, song@kernel.org, stable@vger.kernel.org, xiam0nd.tong@gmail.com Subject: Re: [PATCH] md: md2: fix an incorrect NULL check on list iterator Date: Mon, 28 Mar 2022 15:56:28 +0800 Message-Id: <20220328075628.25545-1-xiam0nd.tong@gmail.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: References: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > I'd suggest to rephrase the subject to "md: fix an incorrect NULL check > in md_reload_sb". Thank you for the suggestion, i will take it in PATCH v2. > > - if (!rdev || rdev->desc_nr != nr) { > > + if (!rdev) { > > pr_warn("%s: %d Could not find rdev with nr %d\n", __func__, __LINE__, nr); > > return; > > } > > I guess we only need to check desc_nr since rdev should always be valid > , and IMO the fix tag > is not necessary. No. At least from the pr_warn log, the list can be empty or no element found in it. If this cases happen, the 'rdev' will be an invalid pointer that point to a invalid struct containning the HEAD '&((mddev)->disks)'. So this fix is necessary. -- Xiaomeng Tong