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=-8.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_MUTT autolearn=ham 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 D0632C04AB4 for ; Fri, 17 May 2019 08:26:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9D08820868 for ; Fri, 17 May 2019 08:26:47 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="IDr7/lKg" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728438AbfEQI0q (ORCPT ); Fri, 17 May 2019 04:26:46 -0400 Received: from mail-pf1-f194.google.com ([209.85.210.194]:47032 "EHLO mail-pf1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727726AbfEQI0q (ORCPT ); Fri, 17 May 2019 04:26:46 -0400 Received: by mail-pf1-f194.google.com with SMTP id y11so3312180pfm.13 for ; Fri, 17 May 2019 01:26:46 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=date:from:to:cc:subject:message-id:mime-version:content-disposition :user-agent; bh=3ii3urujYGVVyIDraN70rev/XODhbjkZr5+BEyKlbDU=; b=IDr7/lKglqdHsGzVnubyhU2QO5rVQxhkW/MANbgk05yD28L6NUEdgKUm5h+JrRQeOE EhMdnDhkgmMczul7077EXJDZIF9fagBjdJcyA+105Xu1kcDw50sN9EOaIx1uXDdeqFdk fd5JQbXvkqtY2x0b1CLuMmq2voBVDYR1UNzqUke3TQ2+FrxdxKToMv896+Vq7nCuia0V d3/o5uDUbIWqECX7m5C/popc6bTPelmCA0e6rfZVYldSVeGwx7H+iDCc8YwaAEH1zb00 +DEcn8a3Mc4ogSqycITCDl7ANG44ZGJokG8DQry1GHCzuIzXuT7K+Ht8I4+b+o6qFE2a RgyA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:mime-version :content-disposition:user-agent; bh=3ii3urujYGVVyIDraN70rev/XODhbjkZr5+BEyKlbDU=; b=Ia9joT0ok4GlGRbk+850uQ1ALMdNbDPK7G0awTOcpc5EVJyeu99vaTjIXYlNSEJQ4l NXffYR25Rzob7cpHGEUaMUKr1Gyt5A7X7Hvs/A7QRTe12Pc8qquaj7ee94CZ+5iIJ4Lw CiyBRr2y/V+58qZEVdtcNEVRf2Zb5qJAC9wOmn07D4LxVO0nLfu7N4dngIy69KtLWDdd HlaEXzUN8Slj5U1re3EU9/14K7SokiGMBiv3ed5M60NM5PZ9Iq+6tMihlHRYtE+ruru1 Gj+Rpoqu7+2bClzl9TC51jA2KSZ+x5r+XKOLWa0XSxa/zhL7CbjLVmPmjf8zpVMiUohb I4BQ== X-Gm-Message-State: APjAAAVoB76FrgQqQCkavMLS3W+JdYHO0OJ9Yv42mZZOoApa/LxJqFXs Kz0SMOIwfvnveMFROKjU8nG3kC1IQjg= X-Google-Smtp-Source: APXvYqz9nrUQmFl9lvrOxqgmIRPI4b0G396uDlRR3vxBDHu/SdZMxg7PPB6QZQLNCetIRT3Cwx99Cg== X-Received: by 2002:a63:231d:: with SMTP id j29mr29530998pgj.278.1558081605760; Fri, 17 May 2019 01:26:45 -0700 (PDT) Received: from zhanggen-UX430UQ ([66.42.35.75]) by smtp.gmail.com with ESMTPSA id d15sm10977168pfr.179.2019.05.17.01.26.40 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 17 May 2019 01:26:45 -0700 (PDT) Date: Fri, 17 May 2019 16:26:33 +0800 From: Gen Zhang To: ard.biesheuvel@linaro.org, dvhart@infradead.org Cc: linux-kernel@vger.kernel.org Subject: [PATCH] efi_64: Fix a missing-check bug in arch/x86/platform/efi/efi_64.c of Linux 5.1 Message-ID: <20190517082633.GA3890@zhanggen-UX430UQ> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org save_pgd is allocated by kmalloc_array. And it is dereferenced in the following codes. However, memory allocation functions such as kmalloc_array may fail. Dereferencing this save_pgd null pointer may cause the kernel go wrong. Thus we should check this allocation and add error handling code. Signed-off-by: Gen Zhang --- diff --git a/arch/x86/platform/efi/efi_64.c b/arch/x86/platform/efi/efi_64.c index cf0347f..fb9ae57 100644 --- a/arch/x86/platform/efi/efi_64.c +++ b/arch/x86/platform/efi/efi_64.c @@ -91,6 +91,8 @@ pgd_t * __init efi_call_phys_prolog(void) n_pgds = DIV_ROUND_UP((max_pfn << PAGE_SHIFT), PGDIR_SIZE); save_pgd = kmalloc_array(n_pgds, sizeof(*save_pgd), GFP_KERNEL); + if (!save_pgd) + goto err; /* * Build 1:1 identity mapping for efi=old_map usage. Note that @@ -142,6 +144,9 @@ pgd_t * __init efi_call_phys_prolog(void) __flush_tlb_all(); return save_pgd; +err: + __flush_tlb_all(); + return ERR_PTR(-ENOMEM); } void __init efi_call_phys_epilog(pgd_t *save_pgd) ---