From patchwork Thu Oct 6 15:08:42 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Ahern X-Patchwork-Id: 13000471 X-Patchwork-Delegate: kuba@kernel.org 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 3D457C433FE for ; Thu, 6 Oct 2022 15:08:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229991AbiJFPIt (ORCPT ); Thu, 6 Oct 2022 11:08:49 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35286 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229575AbiJFPIs (ORCPT ); Thu, 6 Oct 2022 11:08:48 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C626A8A7DD for ; Thu, 6 Oct 2022 08:08:46 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 64CA4619D7 for ; Thu, 6 Oct 2022 15:08:46 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 73118C433D6; Thu, 6 Oct 2022 15:08:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1665068925; bh=2qW+XNIgfVM7t955OqrqlE4po7DIpRtmAJc1p66VPos=; h=From:To:Cc:Subject:Date:From; b=oaNab+3hRdWGNfGH5CUfOC+Ghcnx9yXrzRLnJCmXqwj1XAGC8xLSAt529oqAE/LdD J/Hcj+3oLcmJuWaAOHHb4/ZRY6OUc+YhyB139c/++7XKd9fWeXD1bNApaay4kptWlD VF6FA3NJYhfT/OjuoWQVtD//+sKwAA7pGRO5I+pP1jppmvF5x0bZwzKwayxoI0WrmS eLP6Ylk7dFY3RwOf0M67Z96RsSN5zhVf59rsFnxEo4KnAGYW2jE1p4mzL55lcAYFDi YE8LkYIEcqhaN89Gqo7X6MGExiabf3xRZVP5J6tJtKJul/AcR5X+AthEsbdPWG+cIt jgJuFSIOm53IQ== From: David Ahern To: kuba@kernel.org, davem@davemloft.net, pabeni@redhat.com Cc: netdev@vger.kernel.org, idosch@idosch.org, David Ahern , Gwangun Jung Subject: [PATCH v2 net] ipv4: Handle attempt to delete multipath route when fib_info contains an nh reference Date: Thu, 6 Oct 2022 09:08:42 -0600 Message-Id: <20221006150842.9336-1-dsahern@kernel.org> X-Mailer: git-send-email 2.37.0 (Apple Git-136) MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org Gwangun Jung reported a slab-out-of-bounds access in fib_nh_match: fib_nh_match+0xf98/0x1130 linux-6.0-rc7/net/ipv4/fib_semantics.c:961 fib_table_delete+0x5f3/0xa40 linux-6.0-rc7/net/ipv4/fib_trie.c:1753 inet_rtm_delroute+0x2b3/0x380 linux-6.0-rc7/net/ipv4/fib_frontend.c:874 Separate nexthop objects are mutually exclusive with the legacy multipath spec. Fix fib_nh_match to return if the config for the to be deleted route contains a multipath spec while the fib_info is using a nexthop object. Fixes: 493ced1ac47c ("ipv4: Allow routes to use nexthop objects") Fixes: 6bf92d70e690 ("net: ipv4: fix route with nexthop object delete warning") Reported-by: Gwangun Jung Signed-off-by: David Ahern --- v2: - moved the fi->nh check up and added second Fixes tag (Ido's comments) net/ipv4/fib_semantics.c | 12 ++++++++---- tools/testing/selftests/net/fib_nexthops.sh | 5 +++++ 2 files changed, 13 insertions(+), 4 deletions(-) diff --git a/net/ipv4/fib_semantics.c b/net/ipv4/fib_semantics.c index 2dc97583d279..85fc4afec7fb 100644 --- a/net/ipv4/fib_semantics.c +++ b/net/ipv4/fib_semantics.c @@ -888,13 +888,13 @@ int fib_nh_match(struct net *net, struct fib_config *cfg, struct fib_info *fi, return 1; } + /* cannot match on nexthop object attributes */ + if (fi->nh) + return 1; + if (cfg->fc_oif || cfg->fc_gw_family) { struct fib_nh *nh; - /* cannot match on nexthop object attributes */ - if (fi->nh) - return 1; - nh = fib_info_nh(fi, 0); if (cfg->fc_encap) { if (fib_encap_match(net, cfg->fc_encap_type, @@ -926,6 +926,10 @@ int fib_nh_match(struct net *net, struct fib_config *cfg, struct fib_info *fi, if (!cfg->fc_mp) return 0; + /* multipath spec and nexthop id are mutually exclusive */ + if (fi->nh) + return 1; + rtnh = cfg->fc_mp; remaining = cfg->fc_mp_len; diff --git a/tools/testing/selftests/net/fib_nexthops.sh b/tools/testing/selftests/net/fib_nexthops.sh index d5a0dd548989..15556138de76 100755 --- a/tools/testing/selftests/net/fib_nexthops.sh +++ b/tools/testing/selftests/net/fib_nexthops.sh @@ -1223,6 +1223,11 @@ ipv4_fcnal() log_test $rc 0 "Delete nexthop route warning" run_cmd "$IP route delete 172.16.101.1/32 nhid 12" run_cmd "$IP nexthop del id 12" + + run_cmd "$IP nexthop add id 21 via 172.16.1.6 dev veth1" + run_cmd "$IP ro add 172.16.101.0/24 nhid 21" + run_cmd "$IP ro del 172.16.101.0/24 nexthop via 172.16.1.7 dev veth1 nexthop via 172.16.1.8 dev veth1" + log_test $? 1 "Delete multipath route with only nh id based entry" } ipv4_grp_fcnal()