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 X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 C3395C43331 for ; Wed, 1 Apr 2020 16:36:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 63BA0206F8 for ; Wed, 1 Apr 2020 16:36:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1585759018; bh=7KbVJ4pyGWkFPAmW1q226OXHwGc6AKPnrksV39LEdrM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=F6yOcrTSxe0WU7loSg/Rpt1Dcj0Dd+I4hK8CA23YrxE+VHZhTBBUbgvx599x0PVLy f8dxXshcpMiT6Jvy6DH+160wdIsQ7OvjQAfeA1ubK6ZNl9ADJa6y3uTaVEGqFokzr/ DvmzdNmdbxdZCcM3w0eUBBsotqt5Tp98ubCm41r4= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388903AbgDAQg5 (ORCPT ); Wed, 1 Apr 2020 12:36:57 -0400 Received: from mail.kernel.org ([198.145.29.99]:35946 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388500AbgDAQgv (ORCPT ); Wed, 1 Apr 2020 12:36:51 -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 9A52720658; Wed, 1 Apr 2020 16:36:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1585759011; bh=7KbVJ4pyGWkFPAmW1q226OXHwGc6AKPnrksV39LEdrM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=M7LeTBr8wDXDZiUw1SciGzvilTbdEpixyie7hA4kuJm3mczp/rGk0bTi2Jf5u8AWU n7bOAqlgvB97uWUoSEbeBWGKp6TtCgvkwVvRRKXW8hH2NES43nj5ucD1kRYd8TbzVX tKQUvvx2YBQYuDaDZ4+qsOyJ1c5gW+sJOgrRvDwI= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Taehee Yoo , "David S. Miller" Subject: [PATCH 4.9 048/102] hsr: add restart routine into hsr_get_node_list() Date: Wed, 1 Apr 2020 18:17:51 +0200 Message-Id: <20200401161542.149755699@linuxfoundation.org> X-Mailer: git-send-email 2.26.0 In-Reply-To: <20200401161530.451355388@linuxfoundation.org> References: <20200401161530.451355388@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Taehee Yoo [ Upstream commit ca19c70f5225771c05bcdcb832b4eb84d7271c5e ] The hsr_get_node_list() is to send node addresses to the userspace. If there are so many nodes, it could fail because of buffer size. In order to avoid this failure, the restart routine is added. Fixes: f421436a591d ("net/hsr: Add support for the High-availability Seamless Redundancy protocol (HSRv0)") Signed-off-by: Taehee Yoo Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/hsr/hsr_netlink.c | 38 ++++++++++++++++++++++++-------------- 1 file changed, 24 insertions(+), 14 deletions(-) --- a/net/hsr/hsr_netlink.c +++ b/net/hsr/hsr_netlink.c @@ -371,16 +371,14 @@ fail: */ static int hsr_get_node_list(struct sk_buff *skb_in, struct genl_info *info) { - /* For receiving */ - struct nlattr *na; + unsigned char addr[ETH_ALEN]; struct net_device *hsr_dev; - - /* For sending */ struct sk_buff *skb_out; - void *msg_head; struct hsr_priv *hsr; - void *pos; - unsigned char addr[ETH_ALEN]; + bool restart = false; + struct nlattr *na; + void *pos = NULL; + void *msg_head; int res; if (!info) @@ -398,8 +396,9 @@ static int hsr_get_node_list(struct sk_b if (!is_hsr_master(hsr_dev)) goto rcu_unlock; +restart: /* Send reply */ - skb_out = genlmsg_new(NLMSG_GOODSIZE, GFP_ATOMIC); + skb_out = genlmsg_new(GENLMSG_DEFAULT_SIZE, GFP_ATOMIC); if (!skb_out) { res = -ENOMEM; goto fail; @@ -413,17 +412,28 @@ static int hsr_get_node_list(struct sk_b goto nla_put_failure; } - res = nla_put_u32(skb_out, HSR_A_IFINDEX, hsr_dev->ifindex); - if (res < 0) - goto nla_put_failure; + if (!restart) { + res = nla_put_u32(skb_out, HSR_A_IFINDEX, hsr_dev->ifindex); + if (res < 0) + goto nla_put_failure; + } hsr = netdev_priv(hsr_dev); - pos = hsr_get_next_node(hsr, NULL, addr); + if (!pos) + pos = hsr_get_next_node(hsr, NULL, addr); while (pos) { res = nla_put(skb_out, HSR_A_NODE_ADDR, ETH_ALEN, addr); - if (res < 0) + if (res < 0) { + if (res == -EMSGSIZE) { + genlmsg_end(skb_out, msg_head); + genlmsg_unicast(genl_info_net(info), skb_out, + info->snd_portid); + restart = true; + goto restart; + } goto nla_put_failure; + } pos = hsr_get_next_node(hsr, pos, addr); } rcu_read_unlock(); @@ -440,7 +450,7 @@ invalid: return 0; nla_put_failure: - kfree_skb(skb_out); + nlmsg_free(skb_out); /* Fall through */ fail: