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 4B901C7EE29 for ; Mon, 22 May 2023 20:16:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235067AbjEVUQf (ORCPT ); Mon, 22 May 2023 16:16:35 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58590 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233603AbjEVUQP (ORCPT ); Mon, 22 May 2023 16:16:15 -0400 Received: from mail-pf1-x42c.google.com (mail-pf1-x42c.google.com [IPv6:2607:f8b0:4864:20::42c]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 440B3B5 for ; Mon, 22 May 2023 13:16:13 -0700 (PDT) Received: by mail-pf1-x42c.google.com with SMTP id d2e1a72fcca58-64d41d8bc63so2454617b3a.0 for ; Mon, 22 May 2023 13:16:13 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; t=1684786573; x=1687378573; 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=bBzsEFEBaOoamjuMu6tkFnCdq33AsZWodYlngR5umYI=; b=NQpIylAo879lZg+bIGPMAEf7DDZr1HUjRDRjXgFFzOZAqJismdNG2vT6fvEGnxixbE AO59fHineVN3ZV8SGUip2kK2YNl7yCMhINlOucn3D9rFDYquHDJDjZqxyorrI6Aa1PG3 dgDmEFNb5d5Gy4SPsHORvJXWSanJ+OBQLiiBo= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1684786573; x=1687378573; 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=bBzsEFEBaOoamjuMu6tkFnCdq33AsZWodYlngR5umYI=; b=b6EaBHIYWTyNEa/osCMuxkhIed3nTmMNIg57WSerXVyKQ8wy73UGB2/2XTVUMfgLkV Sk7+yaqytfdJVO6JfkqkPsYQNvhL22LATrfOfhW0Nxt70yoL5jpNFR6kdnKJkEcueicE KRBiqzwvK+3MvfeCgkcazvvtQT4iGZ4b84ETEe2J7eRhnKwQBZzCOBh41kpoi0faQFK9 /0miSJQrurOo1B52v298opQ/gNJWz10RE508bhbhWotD4If3GIKbgMUl/VzbLP+ZEcIW +dvj8d75qUO+BW3NplgnLenJEu3KwjnuN2OniGxJJPdPduzA62qb4e6SaEnoiTz6lyie tTwg== X-Gm-Message-State: AC+VfDxUn/tKOKOzeVGi/u5umk62zH19PkCVAb5zlndL3oLFdo2GqrYn 7/4P+mWUtYjNLQhOJzeZZVMoGg== X-Google-Smtp-Source: ACHHUZ5ATfKSsDeoySmt4TpoCC/s6QT9JMih/7kH5QlewrwQzwJyKfURuuEBVyEFMexNU1NyLHmTzg== X-Received: by 2002:a05:6a00:a20:b0:64a:4bfa:6b8d with SMTP id p32-20020a056a000a2000b0064a4bfa6b8dmr16642693pfh.6.1684786572799; Mon, 22 May 2023 13:16:12 -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 d26-20020aa7869a000000b00640ddad2e0dsm4512884pfo.47.2023.05.22.13.16.12 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 22 May 2023 13:16:12 -0700 (PDT) Date: Mon, 22 May 2023 13:16:11 -0700 From: Kees Cook To: Azeem Shaikh Cc: Chun-Kuang Hu , Philipp Zabel , linux-hardening@vger.kernel.org, dri-devel@lists.freedesktop.org, linux-mediatek@lists.infradead.org, linux-kernel@vger.kernel.org, David Airlie , Daniel Vetter , Matthias Brugger , AngeloGioacchino Del Regno , linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH] drm/mediatek: Replace all non-returning strlcpy with strscpy Message-ID: <202305221316.5C8770098@keescook> References: <20230522155306.2336889-1-azeemshaikh38@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20230522155306.2336889-1-azeemshaikh38@gmail.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, May 22, 2023 at 03:53:06PM +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 strscpy(). > No return values were used, so direct replacement is safe. > > [1] https://www.kernel.org/doc/html/latest/process/deprecated.html#strlcpy > [2] https://github.com/KSPP/linux/issues/89 > > Signed-off-by: Azeem Shaikh Reviewed-by: Kees Cook -- Kees Cook