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=-9.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 00627C388F9 for ; Tue, 3 Nov 2020 21:51:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A4BCD207BB for ; Tue, 3 Nov 2020 21:51:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1604440300; bh=BKfdIyt5z62L/599YN5431rgr0e3luTrifZW3PySgKU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=BHZ4KCH7z/oL5EfhrsR7mrB7sAS8S6m2gQwSwL0CGXi+LznQOZma6cx9UghWcUUBp OAOog51nnd6w8IDA+h63IlxXhYW941uaiQfvZJkOntqaod6PSPfnBy3dW1qjYJWpET AqnfBSK9st3e6HIRTrZ5aFH3Uv5Y700fbTu6JWUc= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731428AbgKCVvk (ORCPT ); Tue, 3 Nov 2020 16:51:40 -0500 Received: from mail.kernel.org ([198.145.29.99]:39774 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731449AbgKCUsV (ORCPT ); Tue, 3 Nov 2020 15:48:21 -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 7E75022409; Tue, 3 Nov 2020 20:48:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1604436501; bh=BKfdIyt5z62L/599YN5431rgr0e3luTrifZW3PySgKU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=STqlmSUfP06TL4aDJ2swdTbs6GkSwI7eMJA71x1w8MKOLmhzgR6r/oYOiFlURiMcb 6CbEALWu8lbWSlJqlQUGMPH0bd81K1llTG1O7Uyl1slUFpk5EkdyREaFChJu5K0hG3 Agw31IvMvFmJLHn4SHcNO27Z6UdrsOGaWdhWe92M= 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 5.9 278/391] iio:gyro:itg3200: Fix timestamp alignment and prevent data leak. Date: Tue, 3 Nov 2020 21:35:29 +0100 Message-Id: <20201103203405.793226857@linuxfoundation.org> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20201103203348.153465465@linuxfoundation.org> References: <20201103203348.153465465@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 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 @@ -46,13 +46,20 @@ 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);