From patchwork Mon Nov 9 12:54:54 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 320922 Delivered-To: patch@linaro.org Received: by 2002:a92:7b12:0:0:0:0:0 with SMTP id w18csp1743415ilc; Mon, 9 Nov 2020 05:41:09 -0800 (PST) X-Google-Smtp-Source: ABdhPJxJb5pUEeEjgASNVRQeTh8mkRTznoxVIiWGz8Mv2jxo3XcZ3bxmcBh5WgZHe63hsph6qEOP X-Received: by 2002:a05:6402:1701:: with SMTP id y1mr11029874edu.209.1604929269604; Mon, 09 Nov 2020 05:41:09 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1604929269; cv=none; d=google.com; s=arc-20160816; b=pzhFsUWTJcMhdWwpSuRcUm2RqThZ/AxBgmZgM6FGCV3WSgM90Mq0Tmo1brPvcsZssj CxqyY6tynNMknDjzKXOEo7q6X8w0fqbTTQYMDzB4NV0visp7Jwhrr2USCYVmNqg/e+oD mrNkKMdYBKDPv0dXho6RFupyiIvSiy4ck5gI1UBuSP2P9pAVJQBe7RR+aqYtwZ7UKEuO ZepdGAT7w9Tj5K6TYfyfpcWZD3t0ydFXrx5rzarFJaifQhUtxLaTKNqrc6eVWdKsi2TN vvwJIRrf59qyX/ZMIKhYsdysFZXGiR3goo2oKkr1cK2jfh6/szoaij9+1hpEiJHxt2SM Ri3g== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:mime-version :user-agent:references:in-reply-to:message-id:date:subject:cc:to :from:dkim-signature; bh=YWinaq5EOm0XklRHwf+9L3zMVnVbwTk0ga7+Qq/NsGM=; b=uA9gavSy+Ekuin9AIYlZExRLwYaTqyIrXy8rOTs3sainsqUlDLouqgOW+V1y7lA4O+ avv6FUhG7QDP7aV2yfNR5HJUsgmAKZXJMSTmhROq+TOJ9eTG33b9HYPF4NljpCfN/OB7 X585/HRhDwTrFoeacXhsJ9I67TI+rhFJQ8OWnpU9DQhy6MjAZa6625l7dNnp40yjtGRC 9/pndnYaLdkEbctNx8rcSw4PcJ9lq21bb/nZjyb54S5TsDQemtQWMQj2ghSjZWuJ11/u TCFcAyaaKmA6/4Uq3Ll3sh+7D+RBrBJAsUx/RLbOUwxNEGXCOpLgl//WmgjTeLO3DCww +X4w== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@kernel.org header.s=default header.b=iu9o33Sx; spf=pass (google.com: domain of stable-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=stable-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=linuxfoundation.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [23.128.96.18]) by mx.google.com with ESMTP id i8si6737606ejf.269.2020.11.09.05.41.09; Mon, 09 Nov 2020 05:41:09 -0800 (PST) Received-SPF: pass (google.com: domain of stable-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18; Authentication-Results: mx.google.com; dkim=pass header.i=@kernel.org header.s=default header.b=iu9o33Sx; spf=pass (google.com: domain of stable-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=stable-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=linuxfoundation.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729174AbgKINjM (ORCPT + 15 others); Mon, 9 Nov 2020 08:39:12 -0500 Received: from mail.kernel.org ([198.145.29.99]:56244 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730670AbgKINDk (ORCPT ); Mon, 9 Nov 2020 08:03:40 -0500 Received: from localhost (83-86-74-64.cable.dynamic.v4.ziggo.nl [83.86.74.64]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id A480E22202; Mon, 9 Nov 2020 13:02:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1604926977; bh=/y7H92Kxy/9wo+t0QSJYuIYPw2TgRjpkBGgOFB+T/No=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=iu9o33Sx1m5JquLxP2nBc//Lj8AGQrEy+IpauGD3IOF2e0mJJTzDTqkjzKfdlQaFp 0slAdUIFZ0x+TLEyTopoLCS3N6/RZynLGe7rn3i7l7wT7LSQkptpI6y1CxeTunEQri WMXKe6ElMrbcJlI9MUTcsNHCj1qQI+UXptJlsSKg= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Lars-Peter Clausen , Jonathan Cameron , Andy Shevchenko , Stable@vger.kernel.org Subject: [PATCH 4.9 068/117] iio:gyro:itg3200: Fix timestamp alignment and prevent data leak. Date: Mon, 9 Nov 2020 13:54:54 +0100 Message-Id: <20201109125028.902266505@linuxfoundation.org> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20201109125025.630721781@linuxfoundation.org> References: <20201109125025.630721781@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Jonathan Cameron commit 10ab7cfd5522f0041028556dac864a003e158556 upstream. One of a class of bugs pointed out by Lars in a recent review. iio_push_to_buffers_with_timestamp assumes the buffer used is aligned to the size of the timestamp (8 bytes). This is not guaranteed in this driver which uses a 16 byte array of smaller elements on the stack. This is fixed by using an explicit c structure. As there are no holes in the structure, there is no possiblity of data leakage in this case. The explicit alignment of ts is not strictly necessary but potentially makes the code slightly less fragile. It also removes the possibility of this being cut and paste into another driver where the alignment isn't already true. Fixes: 36e0371e7764 ("iio:itg3200: Use iio_push_to_buffers_with_timestamp()") Reported-by: Lars-Peter Clausen Signed-off-by: Jonathan Cameron Reviewed-by: Andy Shevchenko Cc: Link: https://lore.kernel.org/r/20200722155103.979802-6-jic23@kernel.org Signed-off-by: Greg Kroah-Hartman --- drivers/iio/gyro/itg3200_buffer.c | 13 ++++++++++--- 1 file changed, 10 insertions(+), 3 deletions(-) --- a/drivers/iio/gyro/itg3200_buffer.c +++ b/drivers/iio/gyro/itg3200_buffer.c @@ -49,13 +49,20 @@ static irqreturn_t itg3200_trigger_handl struct iio_poll_func *pf = p; struct iio_dev *indio_dev = pf->indio_dev; struct itg3200 *st = iio_priv(indio_dev); - __be16 buf[ITG3200_SCAN_ELEMENTS + sizeof(s64)/sizeof(u16)]; + /* + * Ensure correct alignment and padding including for the + * timestamp that may be inserted. + */ + struct { + __be16 buf[ITG3200_SCAN_ELEMENTS]; + s64 ts __aligned(8); + } scan; - int ret = itg3200_read_all_channels(st->i2c, buf); + int ret = itg3200_read_all_channels(st->i2c, scan.buf); if (ret < 0) goto error_ret; - iio_push_to_buffers_with_timestamp(indio_dev, buf, pf->timestamp); + iio_push_to_buffers_with_timestamp(indio_dev, &scan, pf->timestamp); iio_trigger_notify_done(indio_dev->trig);