From patchwork Wed Mar 9 03:09:16 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Wenchao Hao X-Patchwork-Id: 12773859 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id AAA7DC433EF for ; Tue, 8 Mar 2022 13:58:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1347289AbiCHN7m (ORCPT ); Tue, 8 Mar 2022 08:59:42 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45414 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1347276AbiCHN7j (ORCPT ); Tue, 8 Mar 2022 08:59:39 -0500 Received: from szxga03-in.huawei.com (szxga03-in.huawei.com [45.249.212.189]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2947B1A81A; Tue, 8 Mar 2022 05:58:42 -0800 (PST) Received: from dggpemm500021.china.huawei.com (unknown [172.30.72.56]) by szxga03-in.huawei.com (SkyGuard) with ESMTP id 4KCcJz4l9mz9sS1; Tue, 8 Mar 2022 21:54:59 +0800 (CST) Received: from dggpemm500017.china.huawei.com (7.185.36.178) by dggpemm500021.china.huawei.com (7.185.36.109) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.21; Tue, 8 Mar 2022 21:58:40 +0800 Received: from huawei.com (10.175.101.6) by dggpemm500017.china.huawei.com (7.185.36.178) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.21; Tue, 8 Mar 2022 21:58:39 +0800 From: Wenchao Hao To: Mike Christie , Lee Duncan , Chris Leech , "James E . J . Bottomley" , "Martin K . Petersen" , , , CC: Wu Bo , Zhiqiang Liu , , Wenchao Hao Subject: [PATCH v2 3/3] scsi:libiscsi: teardown iscsi_cls_conn gracefully Date: Tue, 8 Mar 2022 22:09:16 -0500 Message-ID: <20220309030916.2932316-4-haowenchao@huawei.com> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20220309030916.2932316-1-haowenchao@huawei.com> References: <20220309030916.2932316-1-haowenchao@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.175.101.6] X-ClientProxiedBy: dggems706-chm.china.huawei.com (10.3.19.183) To dggpemm500017.china.huawei.com (7.185.36.178) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org commit 1b8d0300a3e9 ("scsi: libiscsi: Fix UAF in iscsi_conn_get_param()/iscsi_conn_teardown()") fixed an UAF in iscsi_conn_get_param() and introduced 2 tmp_xxx varibles, the implement looks ugly. We can fix this UAF with the help of device_del() gracefully. Call iscsi_remove_conn() at the beginning of iscsi_conn_teardown would make userspace unable to see iscsi_cls_conn any more, then we can free memory safely. Signed-off-by: Wenchao Hao Signed-off-by: Wu Bo --- drivers/scsi/libiscsi.c | 8 ++++---- drivers/scsi/scsi_transport_iscsi.c | 3 ++- 2 files changed, 6 insertions(+), 5 deletions(-) diff --git a/drivers/scsi/libiscsi.c b/drivers/scsi/libiscsi.c index 43f903bce0b8..0d57521751dd 100644 --- a/drivers/scsi/libiscsi.c +++ b/drivers/scsi/libiscsi.c @@ -3109,8 +3109,8 @@ void iscsi_conn_teardown(struct iscsi_cls_conn *cls_conn) { struct iscsi_conn *conn = cls_conn->dd_data; struct iscsi_session *session = conn->session; - char *tmp_persistent_address = conn->persistent_address; - char *tmp_local_ipaddr = conn->local_ipaddr; + + iscsi_remove_conn(cls_conn); del_timer_sync(&conn->transport_timer); @@ -3132,6 +3132,8 @@ void iscsi_conn_teardown(struct iscsi_cls_conn *cls_conn) spin_lock_bh(&session->frwd_lock); free_pages((unsigned long) conn->data, get_order(ISCSI_DEF_MAX_RECV_SEG_LEN)); + kfree(conn->persistent_address); + kfree(conn->local_ipaddr); /* regular RX path uses back_lock */ spin_lock_bh(&session->back_lock); kfifo_in(&session->cmdpool.queue, (void*)&conn->login_task, @@ -3143,8 +3145,6 @@ void iscsi_conn_teardown(struct iscsi_cls_conn *cls_conn) mutex_unlock(&session->eh_mutex); iscsi_destroy_conn(cls_conn); - kfree(tmp_persistent_address); - kfree(tmp_local_ipaddr); } EXPORT_SYMBOL_GPL(iscsi_conn_teardown); diff --git a/drivers/scsi/scsi_transport_iscsi.c b/drivers/scsi/scsi_transport_iscsi.c index ca724eed4f4d..7b4d998708e7 100644 --- a/drivers/scsi/scsi_transport_iscsi.c +++ b/drivers/scsi/scsi_transport_iscsi.c @@ -2165,6 +2165,7 @@ static int iscsi_iter_destroy_conn_fn(struct device *dev, void *data) { if (!iscsi_is_conn_dev(dev)) return 0; + iscsi_remove_conn(iscsi_dev_to_conn(dev)); return iscsi_destroy_conn(iscsi_dev_to_conn(dev)); } @@ -2463,7 +2464,7 @@ int iscsi_destroy_conn(struct iscsi_cls_conn *conn) transport_unregister_device(&conn->dev); ISCSI_DBG_TRANS_CONN(conn, "Completing conn destruction\n"); - device_unregister(&conn->dev); + iscsi_free_conn(conn); return 0; } EXPORT_SYMBOL_GPL(iscsi_destroy_conn);