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=-0.9 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS, URIBL_BLOCKED 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 78840C43140 for ; Wed, 20 Jun 2018 18:27:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 35DC0204EC for ; Wed, 20 Jun 2018 18:27:32 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="X/B5l8My" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 35DC0204EC Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=chromium.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754750AbeFTS1a (ORCPT ); Wed, 20 Jun 2018 14:27:30 -0400 Received: from mail-pg0-f67.google.com ([74.125.83.67]:35236 "EHLO mail-pg0-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752838AbeFTS10 (ORCPT ); Wed, 20 Jun 2018 14:27:26 -0400 Received: by mail-pg0-f67.google.com with SMTP id i7-v6so203309pgp.2 for ; Wed, 20 Jun 2018 11:27:25 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=date:from:to:cc:subject:message-id:mime-version:content-disposition; bh=cRMUqFnmw99GrtpcjZjr8sw148NRGhLAHTFdivDQJM0=; b=X/B5l8MynhsUtuAwUsmQqV9VMEqWAegW/Q6DvOd1c08BEZ9qABO2vy4PD5jITInG4Z 8IOlRwW3ILo0t1M8N6dL9a/CI1Y8y8fnaXHXld04rkWalf6n40irOwTuUaXRhVjwtjXP +IXGa58lpztnxuQLjLGC2A6TovstIpwD6tPCc= 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; bh=cRMUqFnmw99GrtpcjZjr8sw148NRGhLAHTFdivDQJM0=; b=sNtde4KS4p1lyRZcb8Ylq5ehClwD+os/dTvvwTXtQzttPw2g4NylnDjF9ETsQe3kai KQuDZLrulUfLgzH+ftMrgmKg5FEzcJKJjDEqiUQHo2L1wBqDG4eGNV0ZF9vLiUdqMNIR Ok7xNb6c7nqWIEfA1oUFrKk1E63toULKbXgQB/RBEY9kvlY2b5FDwDsSTxsIzFJb2LU7 p6Nhpx7+ZsmKgGE5GNBe+aecfN2jO7agwOfSdRfhLoA0bjQr0hVAlk3OA04xnRmbonKp RtnpotbWM8ltSbyv4gHjyVUhVM8LTI+EPHjHHV0y43lD3IGx1lBT/8ws3KyjEfsSidne jNQA== X-Gm-Message-State: APt69E2lK73S6pa+4vzd1Qo56lYOBVwi3IITX2W1DRAJxJoYYPrWsqlE dGo03AV3NrypTXBhzKrP/bTC8w== X-Google-Smtp-Source: ADUXVKKE/XDzdoBaRw7wcI2UaP0TCsZAOoekr6kytGYDNOCFUZia0s+z0BvbNxvgCZe9xYpdhIrtjQ== X-Received: by 2002:a65:51cb:: with SMTP id i11-v6mr20052260pgq.320.1529519245376; Wed, 20 Jun 2018 11:27:25 -0700 (PDT) Received: from www.outflux.net (173-164-112-133-Oregon.hfc.comcastbusiness.net. [173.164.112.133]) by smtp.gmail.com with ESMTPSA id j23-v6sm4566967pfi.137.2018.06.20.11.27.24 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Wed, 20 Jun 2018 11:27:24 -0700 (PDT) Date: Wed, 20 Jun 2018 11:27:23 -0700 From: Kees Cook To: David Airlie Cc: linux-kernel@vger.kernel.org, Hans Verkuil , Russell King , dri-devel@lists.freedesktop.org Subject: [PATCH] drm/i2c: tda9950: Remove VLA usage Message-ID: <20180620182723.GA24430@beast> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org In the quest to remove all stack VLA usage from the kernel[1], this sets the buffer to maximum size and adds a sanity check. [1] https://lkml.kernel.org/r/CA+55aFzCG-zNmZwX4A2FQpadafLfEzK6CC=qPXydAacU1RqZWA@mail.gmail.com Signed-off-by: Kees Cook --- drivers/gpu/drm/i2c/tda9950.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/i2c/tda9950.c b/drivers/gpu/drm/i2c/tda9950.c index 3f7396caad48..28314433c351 100644 --- a/drivers/gpu/drm/i2c/tda9950.c +++ b/drivers/gpu/drm/i2c/tda9950.c @@ -76,9 +76,12 @@ struct tda9950_priv { static int tda9950_write_range(struct i2c_client *client, u8 addr, u8 *p, int cnt) { struct i2c_msg msg; - u8 buf[cnt + 1]; + u8 buf[CEC_MAX_MSG_SIZE + 3]; int ret; + if (WARN_ON(cnt > sizeof(buf))) + return -EINVAL; + buf[0] = addr; memcpy(buf + 1, p, cnt); -- 2.17.1 -- Kees Cook Pixel Security