From patchwork Sun Mar 15 17:17:43 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Michal Kubecek X-Patchwork-Id: 222480 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=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED autolearn=unavailable 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 E0CA5C10F29 for ; Sun, 15 Mar 2020 17:17:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BDE2F206E9 for ; Sun, 15 Mar 2020 17:17:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728992AbgCORRp (ORCPT ); Sun, 15 Mar 2020 13:17:45 -0400 Received: from mx2.suse.de ([195.135.220.15]:56438 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728887AbgCORRp (ORCPT ); Sun, 15 Mar 2020 13:17:45 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id 79710ADFE; Sun, 15 Mar 2020 17:17:43 +0000 (UTC) Received: by unicorn.suse.cz (Postfix, from userid 1000) id 2AEF3E0C04; Sun, 15 Mar 2020 18:17:43 +0100 (CET) Message-Id: <6bb18205e2876e4ab804dfc8ec141f895f2fd83a.1584292182.git.mkubecek@suse.cz> In-Reply-To: References: From: Michal Kubecek Subject: [PATCH net 1/3] netlink: allow extack cookie also for error messages To: David Miller , Jakub Kicinski , netdev@vger.kernel.org Cc: Johannes Berg , linux-kernel@vger.kernel.org Date: Sun, 15 Mar 2020 18:17:43 +0100 (CET) Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Commit ba0dc5f6e0ba ("netlink: allow sending extended ACK with cookie on success") introduced a cookie which can be sent to userspace as part of extended ack message in the form of NLMSGERR_ATTR_COOKIE attribute. Currently the cookie is ignored if error code is non-zero but there is no technical reason for such limitation and it can be useful to provide machine parseable information as part of an error message. Include NLMSGERR_ATTR_COOKIE whenever the cookie has been set, regardless of error code. Signed-off-by: Michal Kubecek --- net/netlink/af_netlink.c | 43 ++++++++++++++++------------------------ 1 file changed, 17 insertions(+), 26 deletions(-) diff --git a/net/netlink/af_netlink.c b/net/netlink/af_netlink.c index 5313f1cec170..2f234791b879 100644 --- a/net/netlink/af_netlink.c +++ b/net/netlink/af_netlink.c @@ -2392,19 +2392,14 @@ void netlink_ack(struct sk_buff *in_skb, struct nlmsghdr *nlh, int err, if (nlk_has_extack && extack && extack->_msg) tlvlen += nla_total_size(strlen(extack->_msg) + 1); - if (err) { - if (!(nlk->flags & NETLINK_F_CAP_ACK)) - payload += nlmsg_len(nlh); - else - flags |= NLM_F_CAPPED; - if (nlk_has_extack && extack && extack->bad_attr) - tlvlen += nla_total_size(sizeof(u32)); - } else { + if (err && !(nlk->flags & NETLINK_F_CAP_ACK)) + payload += nlmsg_len(nlh); + else flags |= NLM_F_CAPPED; - - if (nlk_has_extack && extack && extack->cookie_len) - tlvlen += nla_total_size(extack->cookie_len); - } + if (err && nlk_has_extack && extack && extack->bad_attr) + tlvlen += nla_total_size(sizeof(u32)); + if (nlk_has_extack && extack && extack->cookie_len) + tlvlen += nla_total_size(extack->cookie_len); if (tlvlen) flags |= NLM_F_ACK_TLVS; @@ -2427,20 +2422,16 @@ void netlink_ack(struct sk_buff *in_skb, struct nlmsghdr *nlh, int err, WARN_ON(nla_put_string(skb, NLMSGERR_ATTR_MSG, extack->_msg)); } - if (err) { - if (extack->bad_attr && - !WARN_ON((u8 *)extack->bad_attr < in_skb->data || - (u8 *)extack->bad_attr >= in_skb->data + - in_skb->len)) - WARN_ON(nla_put_u32(skb, NLMSGERR_ATTR_OFFS, - (u8 *)extack->bad_attr - - (u8 *)nlh)); - } else { - if (extack->cookie_len) - WARN_ON(nla_put(skb, NLMSGERR_ATTR_COOKIE, - extack->cookie_len, - extack->cookie)); - } + if (err && extack->bad_attr && + !WARN_ON((u8 *)extack->bad_attr < in_skb->data || + (u8 *)extack->bad_attr >= in_skb->data + + in_skb->len)) + WARN_ON(nla_put_u32(skb, NLMSGERR_ATTR_OFFS, + (u8 *)extack->bad_attr - + (u8 *)nlh)); + if (extack->cookie_len) + WARN_ON(nla_put(skb, NLMSGERR_ATTR_COOKIE, + extack->cookie_len, extack->cookie)); } nlmsg_end(skb, rep);