From patchwork Sun May 23 17:00:55 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hans de Goede X-Patchwork-Id: 12274927 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=-16.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,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 F23DEC4707A for ; Sun, 23 May 2021 17:01:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id CD66461261 for ; Sun, 23 May 2021 17:01:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231861AbhEWRCh (ORCPT ); Sun, 23 May 2021 13:02:37 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:24593 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231856AbhEWRCh (ORCPT ); Sun, 23 May 2021 13:02:37 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1621789270; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=yCRp+M6BmquOFM43iImL6UjJTcvuKJRir6amhOD9dvE=; b=fS0dIinFRHcFuJ3qsIbrteOx/dFWhLV/A8MqDs8ADfwLP210Ze++Pt0mhKmc04Kg+xxGYY mOJk2MGLOiOmY3rVvPckqUrLCSSY9KoAi25+LIDfTCS2reJ5r5AMSfTn1rFX56jBdps/bn gZHXxdylKpFjqOCH/OmCw4UzDuqrXr8= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-591-MxP0frqINMaMpbVeLaQtFQ-1; Sun, 23 May 2021 13:01:08 -0400 X-MC-Unique: MxP0frqINMaMpbVeLaQtFQ-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 40F36107ACC7; Sun, 23 May 2021 17:01:07 +0000 (UTC) Received: from x1.localdomain (ovpn-112-61.ams2.redhat.com [10.36.112.61]) by smtp.corp.redhat.com (Postfix) with ESMTP id 0EEAA5D9F2; Sun, 23 May 2021 17:01:05 +0000 (UTC) From: Hans de Goede To: Jonathan Cameron Cc: Hans de Goede , Andy Shevchenko , Lars-Peter Clausen , Jeremy Cline , linux-iio@vger.kernel.org Subject: [PATCH v2 1/9] iio: accel: bmc150: Fix dereferencing the wrong pointer in bmc150_get/set_second_device Date: Sun, 23 May 2021 19:00:55 +0200 Message-Id: <20210523170103.176958-2-hdegoede@redhat.com> In-Reply-To: <20210523170103.176958-1-hdegoede@redhat.com> References: <20210523170103.176958-1-hdegoede@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 Precedence: bulk List-ID: X-Mailing-List: linux-iio@vger.kernel.org The drvdata for iio-parent devices points to the struct iio_dev for the iio-device. So by directly casting the return from i2c_get_clientdata() to struct bmc150_accel_data * the code was ending up storing the second_dev pointer in (and retrieving it from) some semi-random offset inside struct iio_dev, rather then storing it in the second_dev member of the bmc150_accel_data struct. Fix the code to get the struct bmc150_accel_data * pointer to call iio_priv() on the struct iio_dev * returned by i2c_get_clientdata(), so that the correct pointer gets dereferenced. This fixes the following oops on rmmod, caused by trying to dereference the wrong return of bmc150_get_second_device(): [ 238.980737] BUG: unable to handle page fault for address: 0000000000004710 [ 238.980755] #PF: supervisor read access in kernel mode [ 238.980760] #PF: error_code(0x0000) - not-present page ... [ 238.980841] i2c_unregister_device.part.0+0x19/0x60 [ 238.980856] 0xffffffffc0815016 [ 238.980863] i2c_device_remove+0x25/0xb0 [ 238.980869] __device_release_driver+0x180/0x240 [ 238.980876] driver_detach+0xd4/0x120 [ 238.980882] bus_remove_driver+0x5b/0xd0 [ 238.980888] i2c_del_driver+0x44/0x70 While at it also remove the now no longer sensible checks for data being NULL, iio_priv never returns NULL for an iio_dev with non 0 sized private-data. Fixes: 5bfb3a4bd8f6 ("iio: accel: bmc150: Check for a second ACPI device for BOSC0200") Cc: Jeremy Cline Signed-off-by: Hans de Goede --- drivers/iio/accel/bmc150-accel-core.c | 10 +++------- 1 file changed, 3 insertions(+), 7 deletions(-) diff --git a/drivers/iio/accel/bmc150-accel-core.c b/drivers/iio/accel/bmc150-accel-core.c index 04d85ce34e9f..3a3f67930165 100644 --- a/drivers/iio/accel/bmc150-accel-core.c +++ b/drivers/iio/accel/bmc150-accel-core.c @@ -1809,10 +1809,7 @@ EXPORT_SYMBOL_GPL(bmc150_accel_core_probe); struct i2c_client *bmc150_get_second_device(struct i2c_client *client) { - struct bmc150_accel_data *data = i2c_get_clientdata(client); - - if (!data) - return NULL; + struct bmc150_accel_data *data = iio_priv(i2c_get_clientdata(client)); return data->second_device; } @@ -1820,10 +1817,9 @@ EXPORT_SYMBOL_GPL(bmc150_get_second_device); void bmc150_set_second_device(struct i2c_client *client) { - struct bmc150_accel_data *data = i2c_get_clientdata(client); + struct bmc150_accel_data *data = iio_priv(i2c_get_clientdata(client)); - if (data) - data->second_device = client; + data->second_device = client; } EXPORT_SYMBOL_GPL(bmc150_set_second_device);