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 BB990C83F37 for ; Thu, 31 Aug 2023 21:04:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1347485AbjHaVEy (ORCPT ); Thu, 31 Aug 2023 17:04:54 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56526 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231566AbjHaVEw (ORCPT ); Thu, 31 Aug 2023 17:04:52 -0400 Received: from mail-pf1-x430.google.com (mail-pf1-x430.google.com [IPv6:2607:f8b0:4864:20::430]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B1CECE58 for ; Thu, 31 Aug 2023 14:04:49 -0700 (PDT) Received: by mail-pf1-x430.google.com with SMTP id d2e1a72fcca58-68a1af910e0so1006808b3a.2 for ; Thu, 31 Aug 2023 14:04:49 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; t=1693515889; x=1694120689; darn=vger.kernel.org; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=ZIzo2LBD81agdqbnvG9Ei0Uuoz7hAbrfR7IL8DHvg8w=; b=Q1Yw6Zj1JzEnzXZMJcUIu0t2DHu4NoUGGo0U+bDlhOc7kg4wKBexQoh6OjEKcsrxVe uaQ2+DZwgYg2nT9nlmhLqu6gcx25k7oWbTraqbusAUxdwAtY7nOO8xGIY2Boak58ftKt /EebIsxGyAgyeZGEPN9tn38A88hUrvYTL6pRE= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1693515889; x=1694120689; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=ZIzo2LBD81agdqbnvG9Ei0Uuoz7hAbrfR7IL8DHvg8w=; b=TiAQVrM6Qq8rTAjnf0bb2h87c91MQxjwUKMtKZnDRSAAwD/4JnwH8CtusTVAKBuEXU mXm0KCIk0zrHPmoc7+/LQFDZtLUwQeDWahT0hkwlIig9QW5M1bvnnvcRZdNX/verFfUI 0DI00cL7N84/8DXQzWQEn0jlmQyj73nLGWjKs+ccN4qWHYZ6W14I07zI8dw3YRqLZGYx JbDgd7dxAz2bc27vsgOUeH8d8RYrI9Jb6zk8HEWXf8r9i7kBLBRifXnRJPIjH+hzR9T5 45zFKz2VIg6SiRlLRtbRtH4zTowGX5WAPynZaDePQDWR/a13b8JqCHZZ8qtTXjBCibL6 RtWQ== X-Gm-Message-State: AOJu0YyJutN350YtjLy7JpMPy0GnFFDv2EE8rxuw2ZhDf8zKe/jkYq1t QohhZgVKCz74v5uw7f85MwVycw== X-Google-Smtp-Source: AGHT+IG5mBlw3wr5PKsYkuEkTYsra3ZdB1aft7ZjlwjT5ZLwBCBmO/IK0On1ae0vgAiWOWG8dGIzpQ== X-Received: by 2002:a05:6a00:1397:b0:67a:9208:87a with SMTP id t23-20020a056a00139700b0067a9208087amr815479pfg.23.1693515889173; Thu, 31 Aug 2023 14:04:49 -0700 (PDT) Received: from www.outflux.net (198-0-35-241-static.hfc.comcastbusiness.net. [198.0.35.241]) by smtp.gmail.com with ESMTPSA id j13-20020aa7928d000000b00689f8dc26c2sm1678614pfa.133.2023.08.31.14.04.48 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 31 Aug 2023 14:04:48 -0700 (PDT) Date: Thu, 31 Aug 2023 14:04:48 -0700 From: Kees Cook To: Azeem Shaikh Cc: Mark Fasheh , Joel Becker , Joseph Qi , linux-hardening@vger.kernel.org, ocfs2-devel@lists.linux.dev, linux-kernel@vger.kernel.org, Christian Brauner , Dave Chinner , Jan Kara , Jeff Layton Subject: Re: [PATCH v2] fs: ocfs2: Replace strlcpy with sysfs_emit Message-ID: <202308311404.875ABB0A@keescook> References: <20230831193827.1528867-1-azeemshaikh38@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20230831193827.1528867-1-azeemshaikh38@gmail.com> Precedence: bulk List-ID: X-Mailing-List: linux-hardening@vger.kernel.org On Thu, Aug 31, 2023 at 07:38:27PM +0000, Azeem Shaikh wrote: > strlcpy() reads the entire source buffer first. > This read may exceed the destination size limit. > This is both inefficient and can lead to linear read > overflows if a source string is not NUL-terminated [1]. > In an effort to remove strlcpy() completely [2], replace > strlcpy() here with sysfs_emit(). > > Direct replacement is safe here since its ok for `kernel_param_ops.get()` > to return -errno [3]. > > [1] https://www.kernel.org/doc/html/latest/process/deprecated.html#strlcpy > [2] https://github.com/KSPP/linux/issues/89 > [3] https://elixir.bootlin.com/linux/v6.5/source/include/linux/moduleparam.h#L52 > > Signed-off-by: Azeem Shaikh Reviewed-by: Kees Cook -- Kees Cook