From nobody Sun Feb 8 06:49:26 2026 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 3E571EB64D9 for ; Sat, 17 Jun 2023 04:40:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232048AbjFQEk5 (ORCPT ); Sat, 17 Jun 2023 00:40:57 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42378 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229493AbjFQEky (ORCPT ); Sat, 17 Jun 2023 00:40:54 -0400 Received: from mail-oi1-x236.google.com (mail-oi1-x236.google.com [IPv6:2607:f8b0:4864:20::236]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id ABEF81732 for ; Fri, 16 Jun 2023 21:40:53 -0700 (PDT) Received: by mail-oi1-x236.google.com with SMTP id 5614622812f47-39eab4bbe8aso818629b6e.1 for ; Fri, 16 Jun 2023 21:40:53 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20221208; t=1686976853; x=1689568853; h=message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=JdTXgdzdalPUjI3Ht3T1J7by7Wvs6eS5DA4nj1ZXZls=; b=TmUuyayMRWJtcc7lll42NWrHN9ZTGtFNwyTVMVacmssHpZENrIWp01v69I1vBIDcKc GgXNjou394k0gyc/QbrYQz+WhwbuNXlf4xsBLvjSzOEF816LLgMWTKD4mjrAs4o3BG8N 5aYRL0BvfVGKNTp34xnxaLO96YbmNwqWV68RmbQpJDv0TC0kqslkmMAajG7b4lJ+ZA4A QtQKpz+F1HaOB1Kl2uqGcBC2yYXPS4asqtxtiUGbh0kL9TBOU2A9dC6JSpbRZ29zNY5j 97hBT2S74RlieT9iQmLqKPgFtjlcBY/yFoD+DMP2Z5Dwl1rCR/R2LhYINAbjl7/YgWsg BH1g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1686976853; x=1689568853; h=message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=JdTXgdzdalPUjI3Ht3T1J7by7Wvs6eS5DA4nj1ZXZls=; b=dE0vK9sKEeKtJYA2tnwiNXAN7IJa3Z0kQoq3mnZipOHkBG/UmioqhJ+dRzkTrc1c86 h9H0GIoe5IUUPlvdZXY6V3GeZ5xNGRUHuGO4k+1oGSCe21NbJt5PoLpMia4I2buIrrw0 NyDkVvSmkTQG+eGkwNTkEo0S54V+AaBJO3lp25qIS1/wbQ+1WwhAVzVa+OCg9SRdzVrP ayWcPP7ddoL15roDjF39mwB9bvv9hpMMdHZtzs9a2csKJV3kP+Y3P2VsTEGGGyBa+4ky SUgkI2YZkDaH9jig/vf4CKOfa+GAcmYJzDIOvhOXsYMwOdT6vhNPpLx5OhW1SsR1FjyI NB8g== X-Gm-Message-State: AC+VfDyVVtx4Ej++xPj5R41rw+mpiedCVvI1m0N+kdLX0CaTojJD7zIt /zbG0L6lVd64FoMe7s90KAg= X-Google-Smtp-Source: ACHHUZ4gYURqhUUkMPEdrxMDKQayn+10xNi14I/kungRha1hXNiO8wzNWYoiyPAkYT35KE/zYTCRfw== X-Received: by 2002:a05:6808:f92:b0:39a:a77a:eb48 with SMTP id o18-20020a0568080f9200b0039aa77aeb48mr5206055oiw.0.1686976852938; Fri, 16 Jun 2023 21:40:52 -0700 (PDT) Received: from localhost.localdomain ([112.213.33.6]) by smtp.gmail.com with ESMTPSA id kg14-20020a170903060e00b001b06361a38dsm3413397plb.116.2023.06.16.21.40.48 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 16 Jun 2023 21:40:52 -0700 (PDT) From: Liam Ni To: dave.hansen@linux.intel.com, luto@kernel.org, peterz@infradead.org, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, x86@kernel.org, hpa@zytor.com, akpm@linux-foundation.org, rppt@kernel.org Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, zhiguangni01@gmail.com Subject: [PATCH] mm/sparse:avoid null pointer access in memory_present() Date: Sat, 17 Jun 2023 14:40:36 +1000 Message-Id: <20230617044036.3985524-1-zhiguangni01@gmail.com> X-Mailer: git-send-email 2.17.1 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" __nr_to_section() may return a null pointer, before accessing the member variable section_mem_map, we should first determine whether it is a null pointer. Signed-off-by: Liam Ni --- mm/sparse.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/mm/sparse.c b/mm/sparse.c index 4e6e3a9d49dc..37fa3818bc25 100644 --- a/mm/sparse.c +++ b/mm/sparse.c @@ -258,7 +258,7 @@ static void __init memory_present(int nid, unsigned lon= g start, unsigned long en set_section_nid(section, nid); =20 ms =3D __nr_to_section(section); - if (!ms->section_mem_map) { + if (ms && !ms->section_mem_map) { ms->section_mem_map =3D sparse_encode_early_nid(nid) | SECTION_IS_ONLINE; __section_mark_present(ms, section); --=20 2.25.1