From patchwork Mon Jul 20 15:36:41 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: 237561 Delivered-To: patch@linaro.org Received: by 2002:a92:d244:0:0:0:0:0 with SMTP id v4csp2143409ilg; Mon, 20 Jul 2020 09:44:51 -0700 (PDT) X-Google-Smtp-Source: ABdhPJx5x4UjOD7cimNeTjVDvVu4x1YOL7RKuJBOtWqjbuktgdJRel3u1i7arSGpjOtX6PM7uune X-Received: by 2002:a17:906:a44:: with SMTP id x4mr22534405ejf.193.1595263491758; Mon, 20 Jul 2020 09:44:51 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1595263491; cv=none; d=google.com; s=arc-20160816; b=XfQhs4P6yuS0SLdpNvKCYe1T1zWYP5e/kia34udH79OiFO1DCJY1y5rXeWDTE8BV1Y MaPOBByL4YSYEq+UXrd0hx7ZM/FewrQRok5NUVTjfmtVkmJkr966Xb+BSDetObf3hWKT rKeKWop8QGGuT069Fii1idsQaLI2t0KuR2vto+O170A7V4zXrbMiZZfDUB72DSkows2P 5jBrBmsQlDyNFSBp+IoteBlqkfC4QPJuYbLW+2W+ZG7HN65kSTYNVFPc3DwrNCt4DdjL b08ZyODFJvceGc+hU073dd9pA48dOp5eeHegyyM7nr44Yr2kxmUVC6vPJBHAZo2HEKR1 z96A== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:content-transfer-encoding:mime-version :user-agent:references:in-reply-to:message-id:date:subject:cc:to :from:dkim-signature; bh=FyEfiEanleHIkCwrmFojBZ2sZnDFFvemdHTFLx31pNg=; b=E/EFOMRExL8Y/hMAxzuKTCtWVrin8DcBR8BufIyI1cF57ZFRRcPOuwK4BFkhAoPXdt CZe5keCs5DqLqe5f1eZqBZiAM9gHOr8Rp6xiv/dDFOxSHaA8XIup5Cn17zHgkiQWTfEc ejPvjhiXH7voGm8YQLtpIfoU+Z4YZ8lSCd5Tq2aGPwtqSYyIEHz+QPF59MNsPFW9pg05 XklCNlY3tAzv9CywFkcm38IidqK77t79bLkqYKfVtkknqe+aMvmSp1zWoxp9ceQ3HvlA d+ZpI2HIxxt5MJKlJQka1ML79Wm7WCIT9CBMynFgj0qb8sBN7z6LOQjMBf2XgQILU9CC e9Yw== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@kernel.org header.s=default header.b=eosXuhfk; 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 Return-Path: Received: from vger.kernel.org (vger.kernel.org. [23.128.96.18]) by mx.google.com with ESMTP id o10si11013381edr.168.2020.07.20.09.44.51; Mon, 20 Jul 2020 09:44:51 -0700 (PDT) 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=eosXuhfk; 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 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729898AbgGTPlb (ORCPT + 15 others); Mon, 20 Jul 2020 11:41:31 -0400 Received: from mail.kernel.org ([198.145.29.99]:33406 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729895AbgGTPla (ORCPT ); Mon, 20 Jul 2020 11:41:30 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (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 066B322CF7; Mon, 20 Jul 2020 15:41:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1595259689; bh=eVx2whG+iEhdi/wNAA8mHJvtFWijfFiSbn2YqjBTA2Q=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=eosXuhfkhd9KI6B5CVtkAlxHOPYh3Bmuenz9MK785357xggTqwJksY9XRrmtn5nC8 OEb2fj+9S60BtMoQtjy7Q2KBgT7HCR315DoGIP5JvEygb5qTyMETgmWwtaKFqZuks0 +PMTVaLNxe5Jx4jLcl7gNixyM/HFDYzjinGxWCmo= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Lars-Peter Clausen , Jonathan Cameron , Tomasz Duszynski , Stable@vger.kernel.org Subject: [PATCH 4.9 45/86] iio:pressure:ms5611 Fix buffer element alignment Date: Mon, 20 Jul 2020 17:36:41 +0200 Message-Id: <20200720152755.428091647@linuxfoundation.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200720152753.138974850@linuxfoundation.org> References: <20200720152753.138974850@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Jonathan Cameron commit 8db4afe163bbdd93dca6fcefbb831ef12ecc6b4d 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 an array of smaller elements on the stack. Here there is no data leak possibility so use an explicit structure on the stack to ensure alignment and nice readable fashion. The forced alignment of ts isn't strictly necessary in this driver as the padding will be correct anyway (there isn't any). However it is probably less fragile to have it there and it acts as documentation of the requirement. Fixes: 713bbb4efb9dc ("iio: pressure: ms5611: Add triggered buffer support") Reported-by: Lars-Peter Clausen Signed-off-by: Jonathan Cameron Acked-by: Tomasz Duszynski Cc: Signed-off-by: Greg Kroah-Hartman --- drivers/iio/pressure/ms5611_core.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) --- a/drivers/iio/pressure/ms5611_core.c +++ b/drivers/iio/pressure/ms5611_core.c @@ -215,16 +215,21 @@ static irqreturn_t ms5611_trigger_handle struct iio_poll_func *pf = p; struct iio_dev *indio_dev = pf->indio_dev; struct ms5611_state *st = iio_priv(indio_dev); - s32 buf[4]; /* s32 (pressure) + s32 (temp) + 2 * s32 (timestamp) */ + /* Ensure buffer elements are naturally aligned */ + struct { + s32 channels[2]; + s64 ts __aligned(8); + } scan; int ret; mutex_lock(&st->lock); - ret = ms5611_read_temp_and_pressure(indio_dev, &buf[1], &buf[0]); + ret = ms5611_read_temp_and_pressure(indio_dev, &scan.channels[1], + &scan.channels[0]); mutex_unlock(&st->lock); if (ret < 0) goto err; - iio_push_to_buffers_with_timestamp(indio_dev, buf, + iio_push_to_buffers_with_timestamp(indio_dev, &scan, iio_get_time_ns(indio_dev)); err: