From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mateusz Bajorski Subject: [PATCH] Added NLM_F_EXCL support to fib_nl_newrule Date: Fri, 20 May 2016 17:58:23 +0200 Message-ID: <573F341F.7020302@nokia.com> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit To: Return-path: Received: from mail-am1on0142.outbound.protection.outlook.com ([157.56.112.142]:43066 "EHLO emea01-am1-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1753958AbcETP5E (ORCPT ); Fri, 20 May 2016 11:57:04 -0400 Sender: netdev-owner@vger.kernel.org List-ID: When adding rule with NLM_F_EXCL flag then check if the same rule exist. If yes then exit with -EEXIST. This is already implemented in iproute2: if (cmd == RTM_NEWRULE) { req.n.nlmsg_flags |= NLM_F_CREATE|NLM_F_EXCL; req.r.rtm_type = RTN_UNICAST; } Tested ipv4 and ipv6 with net-next linux on qemu x86 expected behavior after patch: localhost ~ # ip rule 0: from all lookup local 32766: from all lookup main 32767: from all lookup default localhost ~ # ip rule add from 10.46.177.97 lookup 104 pref 1005 localhost ~ # ip rule add from 10.46.177.97 lookup 104 pref 1005 RTNETLINK answers: File exists localhost ~ # ip rule 0: from all lookup local 1005: from 10.46.177.97 lookup 104 32766: from all lookup main 32767: from all lookup default There was already topic regarding this but I don't see any changes merged and problem still occurs. https://lkml.kernel.org/r/1135778809.5944.7.camel+%28%29+localhost+%21+localdomain Signed-off-by: Mateusz Bajorski --- net/core/fib_rules.c | 41 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 41 insertions(+) diff --git a/net/core/fib_rules.c b/net/core/fib_rules.c index 840aceb..b9816a3 100644 --- a/net/core/fib_rules.c +++ b/net/core/fib_rules.c @@ -291,6 +291,47 @@ static int fib_nl_newrule(struct sk_buff *skb, struct nlmsghdr* nlh) if (err < 0) goto errout; + if (nlh->nlmsg_flags & NLM_F_EXCL) { + list_for_each_entry(rule, &ops->rules_list, list) { + if (frh->action && (frh->action != rule->action)) + continue; + + if (frh_get_table(frh, tb) && + frh_get_table(frh, tb) != rule->table) + continue; + + if (tb[FRA_PRIORITY] && + rule->pref != nla_get_u32(tb[FRA_PRIORITY])) + continue; + + if (tb[FRA_IIFNAME] && + nla_strcmp(tb[FRA_IIFNAME], rule->iifname)) + continue; + + if (tb[FRA_OIFNAME] && + nla_strcmp(tb[FRA_OIFNAME], rule->oifname)) + continue; + + if (tb[FRA_FWMARK] && + rule->mark != nla_get_u32(tb[FRA_FWMARK])) + continue; + + if (tb[FRA_FWMASK] && + rule->mark_mask != nla_get_u32(tb[FRA_FWMASK])) + continue; + + if (tb[FRA_TUN_ID] && + rule->tun_id != nla_get_be64(tb[FRA_TUN_ID])) + continue; + + if (!ops->compare(rule, frh, tb)) + continue; + + err = -EEXIST; + goto errout; + } + } + rule = kzalloc(ops->rule_size, GFP_KERNEL); if (rule == NULL) { err = -ENOMEM; -- 2.6.4