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=-13.0 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT 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 0A45AC433E1 for ; Mon, 3 Aug 2020 01:15:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E9BCF206E6 for ; Mon, 3 Aug 2020 01:15:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726891AbgHCBPj (ORCPT ); Sun, 2 Aug 2020 21:15:39 -0400 Received: from mail-qt1-f196.google.com ([209.85.160.196]:33140 "EHLO mail-qt1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726534AbgHCBPi (ORCPT ); Sun, 2 Aug 2020 21:15:38 -0400 Received: by mail-qt1-f196.google.com with SMTP id 6so27200491qtt.0 for ; Sun, 02 Aug 2020 18:15:37 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=UqKzpllSGPPCUJdcTHjuzKk2JONMRxxf8Mio+enWVv8=; b=OKAA42CZW6QFPqdsMvPQKYQAZcpP3XSb0FezPhNQu03U47jQ7krL6OZ5RN4rKxOp09 9/Zp8grlGx09aOmebwew3aQWfFoSU4H82s0bPnYjZbNUyk9vku2Fw6OrKgsQKlmcrGsJ hdajTB0hzDpCzQHwE30CTb5eMfG5x+/4aRHq2GZNpeXPrrhtQfX5YyBXQBpe0TZrHCfl cmuOH9j3/c/T2BEPAslvtJwJQwSPzl3tp/HvjZNazdiy+iuExkhtKKldVlB1JEX712bX OazPCtIevBOz6Xh3jmp/NbPXuwvtInl77U9ie1ZCzQEogAkBD3CwQdudV01ES5suCGZz ARXw== X-Gm-Message-State: AOAM532sN8y/1TmBY09C8pgtfoWGsDm9q/CLXWqVPvEhf2yQTSRCvLQA 0tV5mW3f9aUOEN8FdelJF/A= X-Google-Smtp-Source: ABdhPJzSlBgKojdqHiyy+lQPi+zKAOWmuO450YLVtXJPXjHrO87Bq+y+l4yl8Pa0T/P4oK6Nz0TmYw== X-Received: by 2002:aed:34e2:: with SMTP id x89mr14144623qtd.313.1596417336887; Sun, 02 Aug 2020 18:15:36 -0700 (PDT) Received: from rani.riverdale.lan ([2001:470:1f07:5f3::b55f]) by smtp.gmail.com with ESMTPSA id q29sm22015801qtc.10.2020.08.02.18.15.36 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 02 Aug 2020 18:15:36 -0700 (PDT) From: Arvind Sankar To: Ingo Molnar , Kees Cook Cc: x86@kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH 1/1] x86/kaslr: Replace strlen with strnlen Date: Sun, 2 Aug 2020 21:15:34 -0400 Message-Id: <20200803011534.730645-2-nivedita@alum.mit.edu> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200803011534.730645-1-nivedita@alum.mit.edu> References: <202007311632.54A7554192@keescook> <20200803011534.730645-1-nivedita@alum.mit.edu> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org strnlen is safer in case the command line is not NUL-terminated. Signed-off-by: Arvind Sankar --- arch/x86/boot/compressed/kaslr.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/arch/x86/boot/compressed/kaslr.c b/arch/x86/boot/compressed/kaslr.c index 903ccdca0551..a5842eea84cb 100644 --- a/arch/x86/boot/compressed/kaslr.c +++ b/arch/x86/boot/compressed/kaslr.c @@ -43,6 +43,10 @@ #define STATIC #include +#define _SETUP +#include /* For COMMAND_LINE_SIZE */ +#undef _SETUP + #ifdef CONFIG_X86_5LEVEL unsigned int __pgtable_l5_enabled; unsigned int pgdir_shift __ro_after_init = 39; @@ -278,7 +282,7 @@ static void handle_mem_options(void) if (!args) return; - len = strlen(args); + len = strnlen(args, COMMAND_LINE_SIZE-1); tmp_cmdline = malloc(len + 1); if (!tmp_cmdline) error("Failed to allocate space for tmp_cmdline"); @@ -425,7 +429,7 @@ static void mem_avoid_init(unsigned long input, unsigned long input_size, cmd_line = get_cmd_line_ptr(); /* Calculate size of cmd_line. */ if (cmd_line) { - cmd_line_size = strlen((char *)cmd_line) + 1; + cmd_line_size = strnlen((char *)cmd_line, COMMAND_LINE_SIZE-1) + 1; mem_avoid[MEM_AVOID_CMDLINE].start = cmd_line; mem_avoid[MEM_AVOID_CMDLINE].size = cmd_line_size; add_identity_map(mem_avoid[MEM_AVOID_CMDLINE].start, -- 2.26.2