From patchwork Tue Nov 3 20:37:24 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg Kroah-Hartman X-Patchwork-Id: 320476 Delivered-To: patch@linaro.org Received: by 2002:a92:7b12:0:0:0:0:0 with SMTP id w18csp4920605ilc; Tue, 3 Nov 2020 13:20:40 -0800 (PST) X-Google-Smtp-Source: ABdhPJzgwx19aTY8aydM7bgUPoQU5yRyouQ+0bkDqnJx1N/DkfPCgXPxGfQHedBgLkAuxmwaVR3D X-Received: by 2002:a17:906:b0d7:: with SMTP id bk23mr23052769ejb.103.1604438440080; Tue, 03 Nov 2020 13:20:40 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1604438440; cv=none; d=google.com; s=arc-20160816; b=vF0U3CG/3lGAMa21pat89dUvmGXpIoct5ovRApc4rIY2NvFm/kI78+Uz0ESZbRDfrD QtctJ/GLkMs8qw8CKL0ho5G4kkGrovcp7AEr4dxge4scL4wHb/BowIYjadKv+JqrOtIQ aF22HBPhDG4ihp9RH3FG33sWv0EAyUYkqPgmOkY6kWeBlKbxnVqtIfo48sib+Yhlg7wJ WzpN2/6T5h/o6vkY4b7fWwrb1BWUE05yM8z1FfAeNMQHeG68SWMT/O4AOYfwO4+roTuz dhE8/0fBZ7ldjikyUnxwN+jKvq9Rm9xP82dOVJel0WRS1/ACuj4aJW19W+S9gVVHivgS faMQ== 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=CqlQVSUqDzz6hRi+xOlqTEmrUOc1i10allQUgjXHIdEyq0JzE+pc8feNODyYYHGaiw z+53Aw7OenjvgxpNfr/lCYZGl+mBkYYKa5eAONDjoxW+cb4O8pu8N00Cg02bgUmLIFJI HmRluJfF+b7fNkgiJW5n17tQ8yMpltgpY/8o79L6yF4km5WWOFpYbAFn21rXUyDVn8zV nu4DoO7AgXcanRS4M8msUyMVr1LoXcEfoBC8+SgdLpOI5LcVngIRbvZ4fI89FdWtzNlO 2tLNB1HZtVcclUmn3vTmfwA7jFsCRHEmERk3UUEEn98T1xL4fGfTvKg6fTP66HuWIKWH xK7Q== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@kernel.org header.s=default header.b="jLmi/e/c"; 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 o22si71355ejj.86.2020.11.03.13.20.39; Tue, 03 Nov 2020 13:20:40 -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="jLmi/e/c"; 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 S2388044AbgKCVG6 (ORCPT + 15 others); Tue, 3 Nov 2020 16:06:58 -0500 Received: from mail.kernel.org ([198.145.29.99]:46020 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731404AbgKCVG4 (ORCPT ); Tue, 3 Nov 2020 16:06:56 -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 17C9020757; Tue, 3 Nov 2020 21:06:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1604437615; bh=/y7H92Kxy/9wo+t0QSJYuIYPw2TgRjpkBGgOFB+T/No=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=jLmi/e/c7WF13miuDDIpGkS/tBUZjQRMuwA0mbLd0pYiXB2qG2AkxKNVuHleFlwm4 rUHI70EyICAzr/vugTqy+48Xo3k1JhCW83UnDkvn3LTGllQahsnIa1/gW0KU89GB7F kTOED3NUkUZw4jW3zRc4TkwRRPVwNzyreDHFfBlM= 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 4.19 152/191] iio:gyro:itg3200: Fix timestamp alignment and prevent data leak. Date: Tue, 3 Nov 2020 21:37:24 +0100 Message-Id: <20201103203246.864510812@linuxfoundation.org> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20201103203232.656475008@linuxfoundation.org> References: <20201103203232.656475008@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);