From patchwork Fri Jun 16 11:42:17 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Serhey Popovych X-Patchwork-Id: 776671 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 3wpz4y1fC7z9s8J for ; Fri, 16 Jun 2017 21:42:42 +1000 (AEST) Authentication-Results: ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=gmail.com header.i=@gmail.com header.b="BK8RKURX"; dkim-atps=neutral Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752937AbdFPLmk (ORCPT ); Fri, 16 Jun 2017 07:42:40 -0400 Received: from mail-lf0-f65.google.com ([209.85.215.65]:36803 "EHLO mail-lf0-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750899AbdFPLmj (ORCPT ); Fri, 16 Jun 2017 07:42:39 -0400 Received: by mail-lf0-f65.google.com with SMTP id x81so3885469lfb.3 for ; Fri, 16 Jun 2017 04:42:33 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:subject:date:message-id; bh=5r/nlGd/dv0iVuJbuV3Gx8lD3SfMNWTX8znBK4dQt7Y=; b=BK8RKURXODfzUBwqfnSoJ7Rdb2Gg5NMnKweObc7Fcq0NX1pV3uyZSs/puiZcBZtlpg 6EpXj9y7aAcyRdUXIVcjWto5gN2/kW82DU9OyXQmnL5Y9TsNcWEUpSpVFGie0d7qyVlq oCNCpf8OwOWk/dsab4yFeV5woIMSrswyWJKMd5LzQ6u7NKZt/Wzh9QSHcbcPkbyF58+f U/3dIEJX3VEFCn6Fwd86cSvi5ygKw9wNVZa5cKBUTiHpnezikkxhQyNqXzpNw1LJ176E wZJKEOq/WdPDH2ct8/7M9N3gt+CUcK4q5uZYM7sPrAjtN0ZGvH2GeovDe4Egi7hTyS7M +YFA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:subject:date:message-id; bh=5r/nlGd/dv0iVuJbuV3Gx8lD3SfMNWTX8znBK4dQt7Y=; b=e5UPKNCeFMJ136bSTwW78Bq1XZ+GCVVmFuERVFZeuwyWa23kjbez0mqzOZOGAVf9sK +bDQoGD605MoAkZbMtCitmtEVtC57ExEsa5mEMdxEC1Hpczp/22dZBDT1N0F1Ja91ch/ xQ2oMiRA2EYHqUWSTpb11J7uUacjt6H4myy236PruTCPgjroDuu3N99ETp5WzhT7DOV4 Ev2H/n0R/ZaqwIaSMPGyX3hAO/HIuPNBqSZpz6X1G8kvsemzu6drG75wSRBT1oW4wV98 8TJ5D8lnaxDRpPRWuud1C+4HI6SrQT+X9LPRxL/7++t4spcIgxYNNzan+IYqTUgY0eDL O/6A== X-Gm-Message-State: AKS2vOzKHgq5sF6/A3pTRRqo7ecepKq2VA7oGEAA51Sv12l7DNpM415O BNuermPpTGFAFTD1tDpPXw== X-Received: by 10.25.115.14 with SMTP id o14mr2910003lfc.96.1497613347328; Fri, 16 Jun 2017 04:42:27 -0700 (PDT) Received: from tuxracer.synapse.com ([195.238.92.77]) by smtp.gmail.com with ESMTPSA id 90sm544966lfs.9.2017.06.16.04.42.26 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 16 Jun 2017 04:42:26 -0700 (PDT) From: Serhey Popovych To: netdev@vger.kernel.org Subject: ipv6: Do not leak throw route references Date: Fri, 16 Jun 2017 14:42:17 +0300 Message-Id: <1497613337-24027-1-git-send-email-serhe.popovych@gmail.com> X-Mailer: git-send-email 1.8.3.1 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org While commit 73ba57b (ipv6: fix backtracking for throw routes) does good job on error propagation to the fib_rules_lookup() in fib rules core framework that also corrects throw routes handling, it does not solve route reference leakage problem happened when we return -EAGAIN to the fib_rules_lookup() and leave routing table entry referenced in arg->result. If rule with matched throw route isn't last matched in the list we overwrite arg->result loosing reference on throw route stored previously forever. We also partially revert commit ab997ad (ipv6: fix the incorrect return value of throw route) since we never return routing table entry with dst.error == -EAGAIN when CONFIG_IPV6_MULTIPLE_TABLES is on. Also there is no point to check for RTF_REJECT flag since it is always set throw route. Fixes: 73ba57b (ipv6: fix backtracking for throw routes) Signed-off-by: Serhey Popovych --- net/ipv6/fib6_rules.c | 22 ++++++---------------- net/ipv6/ip6_fib.c | 3 +-- 2 files changed, 7 insertions(+), 18 deletions(-) diff --git a/net/ipv6/fib6_rules.c b/net/ipv6/fib6_rules.c index 11318b7..65a3c62 100644 --- a/net/ipv6/fib6_rules.c +++ b/net/ipv6/fib6_rules.c @@ -33,7 +33,6 @@ struct fib6_rule struct dst_entry *fib6_rule_lookup(struct net *net, struct flowi6 *fl6, int flags, pol_lookup_t lookup) { - struct rt6_info *rt; struct fib_lookup_arg arg = { .lookup_ptr = lookup, .flags = FIB_LOOKUP_NOREF, @@ -42,21 +41,11 @@ struct dst_entry *fib6_rule_lookup(struct net *net, struct flowi6 *fl6, fib_rules_lookup(net->ipv6.fib6_rules_ops, flowi6_to_flowi(fl6), flags, &arg); - rt = arg.result; + if (arg.result) + return arg.result; - if (!rt) { - dst_hold(&net->ipv6.ip6_null_entry->dst); - return &net->ipv6.ip6_null_entry->dst; - } - - if (rt->rt6i_flags & RTF_REJECT && - rt->dst.error == -EAGAIN) { - ip6_rt_put(rt); - rt = net->ipv6.ip6_null_entry; - dst_hold(&rt->dst); - } - - return &rt->dst; + dst_hold(&net->ipv6.ip6_null_entry->dst); + return &net->ipv6.ip6_null_entry->dst; } static int fib6_rule_action(struct fib_rule *rule, struct flowi *flp, @@ -117,7 +106,8 @@ static int fib6_rule_action(struct fib_rule *rule, struct flowi *flp, ipv6_addr_copy(&flp6->saddr, &saddr); } err = rt->dst.error; - goto out; + if (err != -EAGAIN) + goto out; } again: ip6_rt_put(rt); diff --git a/net/ipv6/ip6_fib.c b/net/ipv6/ip6_fib.c index d3cd013..32f91cd 100644 --- a/net/ipv6/ip6_fib.c +++ b/net/ipv6/ip6_fib.c @@ -249,8 +249,7 @@ struct dst_entry *fib6_rule_lookup(struct net *net, struct flowi6 *fl6, table = fib6_get_table(net, RT6_TABLE_MAIN); if (table) { rt = lookup(net, table, fl6, flags); - if (rt->rt6i_flags & RTF_REJECT && - rt->dst.error == -EAGAIN) { + if (rt->dst.error == -EAGAIN) { ip6_rt_put(rt); rt = NULL; }