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 93914C072B5 for ; Wed, 22 May 2019 02:07:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 617F1217D7 for ; Wed, 22 May 2019 02:07:37 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="qeD1Z+S9" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728224AbfEVCHg (ORCPT ); Tue, 21 May 2019 22:07:36 -0400 Received: from mail-pf1-f194.google.com ([209.85.210.194]:33324 "EHLO mail-pf1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727208AbfEVCHg (ORCPT ); Tue, 21 May 2019 22:07:36 -0400 Received: by mail-pf1-f194.google.com with SMTP id z28so455181pfk.0 for ; Tue, 21 May 2019 19:07:35 -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:references:mime-version :content-disposition:content-transfer-encoding:in-reply-to :user-agent; bh=XjZv8VPZY5yPAJVnzsgKE93tbIf6Kof6QehNERCMUpk=; b=qeD1Z+S9sMyldLc0e+aThRlLF6yqkIOo93DnE2pVcJU94KsMO7MhNKx8mSOFJKxROY UwDTwt2OG/V3JEa3YqiiPCyeSUy+KtvcqGP7/k+1EHV2Rq2EvoiVvZ14A/DGlhTNo2qX 3ExDvDLENmnwHWwpdMQ3GckBO4MB0xOCj3aXgjao2KZqjKs7PlYa6zcozWJ4EcYSWbDP Qt55kDO9gN0mV/oaWo3oci9uC6GAyqh+fcfglxH4oc8gGp5g4VnYwCC25mHlGl+u7rYj qQBoDrrBVR7/nkrhxSBh70FzO9CM5RmTWJnD6ObvlypDOr827SyEMS4y73EKK0GFWofS 8Lrw== 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:references :mime-version:content-disposition:content-transfer-encoding :in-reply-to:user-agent; bh=XjZv8VPZY5yPAJVnzsgKE93tbIf6Kof6QehNERCMUpk=; b=izUoY8/TOZCbK+Ijo/nPEtzyhomBN7dK98Qa86u4a3p40I81JDxX7A8Qkm4+p5FQfI TeSQUmCtbUDxzlIu2n7sfRr7Glnhibc5Nav5sPUfViaoQmMvsQQ1jRBwLZRZBl/PrAFP L+NFE43Avhi9zflknPGniT2DgCa/ltSxlKYPmfj7WcGJDJHVztb6Gir88vvDrzmDFKJn W8ZkO5c+OvyyZrzaFXNOfg9jOpQyCejAnaKtKkQB34ydfff+fLvqibzaRi4I0BPGj0ZX fnvEQFVyKm6H94Hqd2724c7rO7y3WuPK/rPbKzV7nd32QuGe/QAqv4awLOkbEDJWXHwN qkpQ== X-Gm-Message-State: APjAAAVBkgy/KqFREv//DBwjyweFWakPp3nNRlNm+fztXrtkBYrBhxfk DbHgCTw9SBQj/leUZXXiMzdJ8Z/6anE= X-Google-Smtp-Source: APXvYqzfgLBunWyLsQElxtkwqOcLss9PkcnCTe4Jf2aIamDd3gse5p+E+Obiu1hU/CIygMErM98YgA== X-Received: by 2002:a63:7146:: with SMTP id b6mr82676079pgn.426.1558490855602; Tue, 21 May 2019 19:07:35 -0700 (PDT) Received: from zhanggen-UX430UQ ([66.42.35.75]) by smtp.gmail.com with ESMTPSA id y10sm33534653pff.4.2019.05.21.19.07.32 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 21 May 2019 19:07:35 -0700 (PDT) Date: Wed, 22 May 2019 10:07:23 +0800 From: Gen Zhang To: Li Zhijian Cc: linux-kernel@vger.kernel.org Subject: Re: [PATCH] initramfs: Fix a missing-check bug in init/initramfs.c Message-ID: <20190522020723.GA5753@zhanggen-UX430UQ> References: <20190522010455.GA4093@zhanggen-UX430UQ> <2c246472-bb1c-1063-1370-33da04af27d0@cn.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <2c246472-bb1c-1063-1370-33da04af27d0@cn.fujitsu.com> 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 On Wed, May 22, 2019 at 10:00:37AM +0800, Li Zhijian wrote: > > On 5/22/19 09:04, Gen Zhang wrote: > >In dir_add(), de and de->name are allocated by kmalloc() and kstrdup(). > >And de->name is dereferenced in the following codes. However, memory > >allocation functions such as kmalloc() and kstrdup() may fail. > >Dereferencing this de->name null pointer may cause the kernel go wrong. > >Thus we should check this allocation. > >Further, if kstrdup() returns NULL, we should free de and panic(). > > > >Signed-off-by: Gen Zhang > > > >--- > >diff --git a/init/initramfs.c b/init/initramfs.c > >index 178130f..dc8063f 100644 > >--- a/init/initramfs.c > >+++ b/init/initramfs.c > >@@ -125,6 +125,10 @@ static void __init dir_add(const char *name, time64_t mtime) > > panic("can't allocate dir_entry buffer"); > > INIT_LIST_HEAD(&de->list); > > de->name = kstrdup(name, GFP_KERNEL); > >+ if (!de->name) { > >+ kfree(de); > >+ panic("can't allocate dir_entry name buffer"); > >+ } > > Looks good > > but the following place should be considered as well i think > 342                                 vcollected = kstrdup(collected, GFP_KERNEL); > 343                                 state = CopyFile; > > > Thanks > Zhijian Thanks for your comments, Zhijian! I thinks you are correct that vcollected should also be checked. I will work on this patch and resubmit it. Thank Gen