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 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1AA87C433F5 for ; Mon, 11 Oct 2021 09:13:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 071D060EB6 for ; Mon, 11 Oct 2021 09:13:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235440AbhJKJO6 (ORCPT ); Mon, 11 Oct 2021 05:14:58 -0400 Received: from szxga03-in.huawei.com ([45.249.212.189]:24236 "EHLO szxga03-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235421AbhJKJO5 (ORCPT ); Mon, 11 Oct 2021 05:14:57 -0400 Received: from dggemv711-chm.china.huawei.com (unknown [172.30.72.53]) by szxga03-in.huawei.com (SkyGuard) with ESMTP id 4HSY2b1XngzQjBW; Mon, 11 Oct 2021 17:11:51 +0800 (CST) Received: from dggpeml500017.china.huawei.com (7.185.36.243) by dggemv711-chm.china.huawei.com (10.1.198.66) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.8; Mon, 11 Oct 2021 17:12:53 +0800 Received: from huawei.com (10.175.103.91) by dggpeml500017.china.huawei.com (7.185.36.243) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.8; Mon, 11 Oct 2021 17:12:53 +0800 From: Yang Yingliang To: , CC: , , , Subject: [PATCH v2] iio: core: fix double free in iio_device_unregister_sysfs() Date: Mon, 11 Oct 2021 17:20:28 +0800 Message-ID: <20211011092028.2310144-1-yangyingliang@huawei.com> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Content-Transfer-Encoding: 7BIT Content-Type: text/plain; charset=US-ASCII X-Originating-IP: [10.175.103.91] X-ClientProxiedBy: dggems706-chm.china.huawei.com (10.3.19.183) To dggpeml500017.china.huawei.com (7.185.36.243) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org I got the double free report: BUG: KASAN: double-free or invalid-free in kfree+0xce/0x390 CPU: 0 PID: 359 Comm: xrun Tainted: G W 5.15.0-rc3-00109-g4dfd49fafc4d-dirty #474 523b7f3c65c42247635e2ac04a95f61f9f36678d Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1.1 04/01/2014 Call Trace: dump_stack_lvl+0xe2/0x152 print_address_description.constprop.7+0x21/0x150 kasan_report_invalid_free+0x6f/0xa0 __kasan_slab_free+0x125/0x140 slab_free_freelist_hook+0x10d/0x240 kfree+0xce/0x390 iio_device_unregister_sysfs+0x108/0x13b [industrialio] iio_dev_release+0x9e/0x10e [industrialio] device_release+0xa5/0x240 kobject_put+0x1e5/0x540 put_device+0x20/0x30 devm_iio_device_release+0x21/0x30 [industrialio] release_nodes+0xc3/0x3b0 devres_release_group+0x1da/0x2c0 i2c_device_probe+0x628/0xbb0 really_probe+0x285/0xc30 If __iio_device_register() fails, iio_dev_opaque->groups will be freed in error path in iio_device_unregister_sysfs(), then iio_dev_release() will call iio_device_unregister_sysfs() again, it causes double free. Set iio_dev_opaque->groups to NULL when it's freed to fix this double free. Fixes: 32f171724e5c ("iio: core: rework iio device group creation") Reported-by: Hulk Robot Reviewed-by: Alexandru Ardelean Signed-off-by: Yang Yingliang --- drivers/iio/industrialio-core.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/iio/industrialio-core.c b/drivers/iio/industrialio-core.c index 2dbb37e09b8c..2dc837db50f7 100644 --- a/drivers/iio/industrialio-core.c +++ b/drivers/iio/industrialio-core.c @@ -1600,6 +1600,7 @@ static void iio_device_unregister_sysfs(struct iio_dev *indio_dev) kfree(iio_dev_opaque->chan_attr_group.attrs); iio_dev_opaque->chan_attr_group.attrs = NULL; kfree(iio_dev_opaque->groups); + iio_dev_opaque->groups = NULL; } static void iio_dev_release(struct device *device) -- 2.25.1