From patchwork Fri Jul 14 05:58:44 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Vignesh Viswanathan X-Patchwork-Id: 703305 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 32A95EB64DA for ; Fri, 14 Jul 2023 05:59:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234860AbjGNF71 (ORCPT ); Fri, 14 Jul 2023 01:59:27 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42602 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229463AbjGNF70 (ORCPT ); Fri, 14 Jul 2023 01:59:26 -0400 Received: from mx0b-0031df01.pphosted.com (mx0b-0031df01.pphosted.com [205.220.180.131]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A0E842D46; Thu, 13 Jul 2023 22:59:24 -0700 (PDT) Received: from pps.filterd (m0279872.ppops.net [127.0.0.1]) by mx0a-0031df01.pphosted.com (8.17.1.19/8.17.1.19) with ESMTP id 36E3uoVa014936; Fri, 14 Jul 2023 05:59:17 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=quicinc.com; h=from : to : cc : subject : date : message-id : in-reply-to : references : mime-version : content-transfer-encoding : content-type; s=qcppdkim1; bh=RmuOwPK4fDHQqvCsQNhf7RiN2U0Gtly3hCNVAGya/PI=; b=VSYuqdeTbQi97wQ2VOQG3Yf79pJEp4zqUnjKa7CJG9QheGl2CNz2egk2HUepzcav61nT dw2B6aYrMlIrhI9uow3XYuAAfCq62W4N9wFm+qdGf+VcYnI/LegujGdmF9n67bWVtQvJ nlH1k7pA8rggRhf2WmUxcxZ/wkMUZgH++lbI7vCX4y8Bn3WpUAO7y0yxFGGvT0CxRBDF eFv1HKuR7fB1QvaZc9VIsvyPtOxQQ/XRmtvmUJc+Gj3rpPgFX3Kg8u/H+24SAFjuQOhV YObbWPxf3kbGf1xyZi6NzLS3CjwUFNpMqm17JlDeZa8Krv33y9M3qIppRZyYYCqbso3t ug== Received: from nalasppmta05.qualcomm.com (Global_NAT1.qualcomm.com [129.46.96.20]) by mx0a-0031df01.pphosted.com (PPS) with ESMTPS id 3rtpukryr3-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 14 Jul 2023 05:59:16 +0000 Received: from nalasex01c.na.qualcomm.com (nalasex01c.na.qualcomm.com [10.47.97.35]) by NALASPPMTA05.qualcomm.com (8.17.1.5/8.17.1.5) with ESMTPS id 36E5xFav026987 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 14 Jul 2023 05:59:15 GMT Received: from hu-viswanat-blr.qualcomm.com (10.80.80.8) by nalasex01c.na.qualcomm.com (10.47.97.35) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1118.30; Thu, 13 Jul 2023 22:59:10 -0700 From: Vignesh Viswanathan To: , , , , , , , CC: , , Vignesh Viswanathan , Simon Horman Subject: [PATCH V2 net-next 1/3] net: qrtr: ns: Change servers radix tree to xarray Date: Fri, 14 Jul 2023 11:28:44 +0530 Message-ID: <20230714055846.1481015-2-quic_viswanat@quicinc.com> X-Mailer: git-send-email 2.41.0 In-Reply-To: <20230714055846.1481015-1-quic_viswanat@quicinc.com> References: <20230714055846.1481015-1-quic_viswanat@quicinc.com> MIME-Version: 1.0 X-Originating-IP: [10.80.80.8] X-ClientProxiedBy: nasanex01a.na.qualcomm.com (10.52.223.231) To nalasex01c.na.qualcomm.com (10.47.97.35) X-QCInternal: smtphost X-Proofpoint-Virus-Version: vendor=nai engine=6200 definitions=5800 signatures=585085 X-Proofpoint-ORIG-GUID: -_kVUiD0au1prNuvgJYoFS_ob9CA4RhU X-Proofpoint-GUID: -_kVUiD0au1prNuvgJYoFS_ob9CA4RhU X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.254,Aquarius:18.0.957,Hydra:6.0.591,FMLib:17.11.176.26 definitions=2023-07-14_02,2023-07-13_01,2023-05-22_02 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 mlxscore=0 malwarescore=0 adultscore=0 lowpriorityscore=0 impostorscore=0 clxscore=1015 bulkscore=0 phishscore=0 suspectscore=0 mlxlogscore=999 priorityscore=1501 spamscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2306200000 definitions=main-2307140055 Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org There is a use after free scenario while iterating through the servers radix tree despite the ns being a single threaded process. This can happen when the radix tree APIs are not synchronized with the rcu_read_lock() APIs. Convert the radix tree for servers to xarray to take advantage of the built in rcu lock usage provided by xarray. Signed-off-by: Chris Lew Signed-off-by: Vignesh Viswanathan Reviewed-by: Simon Horman --- net/qrtr/ns.c | 133 +++++++++----------------------------------------- 1 file changed, 24 insertions(+), 109 deletions(-) diff --git a/net/qrtr/ns.c b/net/qrtr/ns.c index 0f7a729f1a1f..af28d9e6b53f 100644 --- a/net/qrtr/ns.c +++ b/net/qrtr/ns.c @@ -66,7 +66,7 @@ struct qrtr_server { struct qrtr_node { unsigned int id; - struct radix_tree_root servers; + struct xarray servers; }; static struct qrtr_node *node_get(unsigned int node_id) @@ -83,6 +83,7 @@ static struct qrtr_node *node_get(unsigned int node_id) return NULL; node->id = node_id; + xa_init(&node->servers); if (radix_tree_insert(&nodes, node_id, node)) { kfree(node); @@ -193,40 +194,23 @@ static void lookup_notify(struct sockaddr_qrtr *to, struct qrtr_server *srv, static int announce_servers(struct sockaddr_qrtr *sq) { - struct radix_tree_iter iter; struct qrtr_server *srv; struct qrtr_node *node; - void __rcu **slot; + unsigned long index; int ret; node = node_get(qrtr_ns.local_node); if (!node) return 0; - rcu_read_lock(); /* Announce the list of servers registered in this node */ - radix_tree_for_each_slot(slot, &node->servers, &iter, 0) { - srv = radix_tree_deref_slot(slot); - if (!srv) - continue; - if (radix_tree_deref_retry(srv)) { - slot = radix_tree_iter_retry(&iter); - continue; - } - slot = radix_tree_iter_resume(slot, &iter); - rcu_read_unlock(); - + xa_for_each(&node->servers, index, srv) { ret = service_announce_new(sq, srv); if (ret < 0) { pr_err("failed to announce new service\n"); return ret; } - - rcu_read_lock(); } - - rcu_read_unlock(); - return 0; } @@ -256,14 +240,17 @@ static struct qrtr_server *server_add(unsigned int service, goto err; /* Delete the old server on the same port */ - old = radix_tree_lookup(&node->servers, port); + old = xa_store(&node->servers, port, srv, GFP_KERNEL); if (old) { - radix_tree_delete(&node->servers, port); - kfree(old); + if (xa_is_err(old)) { + pr_err("failed to add server [0x%x:0x%x] ret:%d\n", + srv->service, srv->instance, xa_err(old)); + goto err; + } else { + kfree(old); + } } - radix_tree_insert(&node->servers, port, srv); - trace_qrtr_ns_server_add(srv->service, srv->instance, srv->node, srv->port); @@ -280,11 +267,11 @@ static int server_del(struct qrtr_node *node, unsigned int port, bool bcast) struct qrtr_server *srv; struct list_head *li; - srv = radix_tree_lookup(&node->servers, port); + srv = xa_load(&node->servers, port); if (!srv) return -ENOENT; - radix_tree_delete(&node->servers, port); + xa_erase(&node->servers, port); /* Broadcast the removal of local servers */ if (srv->node == qrtr_ns.local_node && bcast) @@ -344,13 +331,12 @@ static int ctrl_cmd_hello(struct sockaddr_qrtr *sq) static int ctrl_cmd_bye(struct sockaddr_qrtr *from) { struct qrtr_node *local_node; - struct radix_tree_iter iter; struct qrtr_ctrl_pkt pkt; struct qrtr_server *srv; struct sockaddr_qrtr sq; struct msghdr msg = { }; struct qrtr_node *node; - void __rcu **slot; + unsigned long index; struct kvec iv; int ret; @@ -361,22 +347,9 @@ static int ctrl_cmd_bye(struct sockaddr_qrtr *from) if (!node) return 0; - rcu_read_lock(); /* Advertise removal of this client to all servers of remote node */ - radix_tree_for_each_slot(slot, &node->servers, &iter, 0) { - srv = radix_tree_deref_slot(slot); - if (!srv) - continue; - if (radix_tree_deref_retry(srv)) { - slot = radix_tree_iter_retry(&iter); - continue; - } - slot = radix_tree_iter_resume(slot, &iter); - rcu_read_unlock(); + xa_for_each(&node->servers, index, srv) server_del(node, srv->port, true); - rcu_read_lock(); - } - rcu_read_unlock(); /* Advertise the removal of this client to all local servers */ local_node = node_get(qrtr_ns.local_node); @@ -387,18 +360,7 @@ static int ctrl_cmd_bye(struct sockaddr_qrtr *from) pkt.cmd = cpu_to_le32(QRTR_TYPE_BYE); pkt.client.node = cpu_to_le32(from->sq_node); - rcu_read_lock(); - radix_tree_for_each_slot(slot, &local_node->servers, &iter, 0) { - srv = radix_tree_deref_slot(slot); - if (!srv) - continue; - if (radix_tree_deref_retry(srv)) { - slot = radix_tree_iter_retry(&iter); - continue; - } - slot = radix_tree_iter_resume(slot, &iter); - rcu_read_unlock(); - + xa_for_each(&local_node->servers, index, srv) { sq.sq_family = AF_QIPCRTR; sq.sq_node = srv->node; sq.sq_port = srv->port; @@ -411,11 +373,7 @@ static int ctrl_cmd_bye(struct sockaddr_qrtr *from) pr_err("failed to send bye cmd\n"); return ret; } - rcu_read_lock(); } - - rcu_read_unlock(); - return 0; } @@ -423,7 +381,6 @@ static int ctrl_cmd_del_client(struct sockaddr_qrtr *from, unsigned int node_id, unsigned int port) { struct qrtr_node *local_node; - struct radix_tree_iter iter; struct qrtr_lookup *lookup; struct qrtr_ctrl_pkt pkt; struct msghdr msg = { }; @@ -432,7 +389,7 @@ static int ctrl_cmd_del_client(struct sockaddr_qrtr *from, struct qrtr_node *node; struct list_head *tmp; struct list_head *li; - void __rcu **slot; + unsigned long index; struct kvec iv; int ret; @@ -477,18 +434,7 @@ static int ctrl_cmd_del_client(struct sockaddr_qrtr *from, pkt.client.node = cpu_to_le32(node_id); pkt.client.port = cpu_to_le32(port); - rcu_read_lock(); - radix_tree_for_each_slot(slot, &local_node->servers, &iter, 0) { - srv = radix_tree_deref_slot(slot); - if (!srv) - continue; - if (radix_tree_deref_retry(srv)) { - slot = radix_tree_iter_retry(&iter); - continue; - } - slot = radix_tree_iter_resume(slot, &iter); - rcu_read_unlock(); - + xa_for_each(&local_node->servers, index, srv) { sq.sq_family = AF_QIPCRTR; sq.sq_node = srv->node; sq.sq_port = srv->port; @@ -501,11 +447,7 @@ static int ctrl_cmd_del_client(struct sockaddr_qrtr *from, pr_err("failed to send del client cmd\n"); return ret; } - rcu_read_lock(); } - - rcu_read_unlock(); - return 0; } @@ -576,13 +518,12 @@ static int ctrl_cmd_del_server(struct sockaddr_qrtr *from, static int ctrl_cmd_new_lookup(struct sockaddr_qrtr *from, unsigned int service, unsigned int instance) { - struct radix_tree_iter node_iter; struct qrtr_server_filter filter; - struct radix_tree_iter srv_iter; struct qrtr_lookup *lookup; + struct qrtr_server *srv; struct qrtr_node *node; - void __rcu **node_slot; - void __rcu **srv_slot; + unsigned long node_idx; + unsigned long srv_idx; /* Accept only local observers */ if (from->sq_node != qrtr_ns.local_node) @@ -601,40 +542,14 @@ static int ctrl_cmd_new_lookup(struct sockaddr_qrtr *from, filter.service = service; filter.instance = instance; - rcu_read_lock(); - radix_tree_for_each_slot(node_slot, &nodes, &node_iter, 0) { - node = radix_tree_deref_slot(node_slot); - if (!node) - continue; - if (radix_tree_deref_retry(node)) { - node_slot = radix_tree_iter_retry(&node_iter); - continue; - } - node_slot = radix_tree_iter_resume(node_slot, &node_iter); - - radix_tree_for_each_slot(srv_slot, &node->servers, - &srv_iter, 0) { - struct qrtr_server *srv; - - srv = radix_tree_deref_slot(srv_slot); - if (!srv) - continue; - if (radix_tree_deref_retry(srv)) { - srv_slot = radix_tree_iter_retry(&srv_iter); - continue; - } - + xa_for_each(&nodes, node_idx, node) { + xa_for_each(&node->servers, srv_idx, srv) { if (!server_match(srv, &filter)) continue; - srv_slot = radix_tree_iter_resume(srv_slot, &srv_iter); - - rcu_read_unlock(); lookup_notify(from, srv, true); - rcu_read_lock(); } } - rcu_read_unlock(); /* Empty notification, to indicate end of listing */ lookup_notify(from, NULL, true);