From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id DE3851EA8D; Mon, 12 Aug 2024 16:11:57 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1723479118; cv=none; b=uCu0R0AEQ1glEhcrOShz11qf/yyF7B1ejrgmCpBJKy1I5Bu0/SyZF/5sNtuShCIFjzk8EImDPTsEffosX2r4lqiwgGK7/VUaLf6CEjNU5WKDLOBfZActZkEXC16rl1wCZDSkqt01T7pS5x8sZui0s6OX5NchAjYZcIfMthQ5ljI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1723479118; c=relaxed/simple; bh=9dehpreKBimegf5mHRwWZ13Ou85v/FR5PBzFdbam7+A=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=aE25L+wtgObnq3R8oGWRHGugFcBdGi0pAr+wKDcojHT5kNJlGfRu5AMMT/uLynZ19aCzNQvkV+SWRaEca27KZk1jCZ9wkL/Vb95UeqnCS6nRsUdo084+uG/anXJcJkJF97KTfFDVc6Zl+UImr0E5bBWJ7IwcGxy48abNsy8OS2I= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=bWBzabhm; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="bWBzabhm" Received: by smtp.kernel.org (Postfix) with ESMTPSA id E9A60C32782; Mon, 12 Aug 2024 16:11:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1723479117; bh=9dehpreKBimegf5mHRwWZ13Ou85v/FR5PBzFdbam7+A=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=bWBzabhmaeZee+Wk9+0xP1X5EjAPjGcNxVrD46zHfr01330SoJDILBzAWIIZ/zDim 1cyy5UbFWbw6WbzMnibdBrZAbnZCuh9tBF8ScuyumnPKgE6ODh/I+CLjIo5MeXWdY4 yCdvpV61LTlCMnXe31QHe8L1Z3GqchT8gb0BNW7U= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Nicolas Dichtel , Jakub Kicinski Subject: [PATCH 6.1 139/150] ipv6: fix source address selection with route leak Date: Mon, 12 Aug 2024 18:03:40 +0200 Message-ID: <20240812160130.535871748@linuxfoundation.org> X-Mailer: git-send-email 2.46.0 In-Reply-To: <20240812160125.139701076@linuxfoundation.org> References: <20240812160125.139701076@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Nicolas Dichtel commit 252442f2ae317d109ef0b4b39ce0608c09563042 upstream. By default, an address assigned to the output interface is selected when the source address is not specified. This is problematic when a route, configured in a vrf, uses an interface from another vrf (aka route leak). The original vrf does not own the selected source address. Let's add a check against the output interface and call the appropriate function to select the source address. CC: stable@vger.kernel.org Fixes: 0d240e7811c4 ("net: vrf: Implement get_saddr for IPv6") Signed-off-by: Nicolas Dichtel Link: https://patch.msgid.link/20240710081521.3809742-3-nicolas.dichtel@6wind.com Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman --- include/net/ip6_route.h | 20 ++++++++++++++------ net/ipv6/ip6_output.c | 1 + net/ipv6/route.c | 2 +- 3 files changed, 16 insertions(+), 7 deletions(-) --- a/include/net/ip6_route.h +++ b/include/net/ip6_route.h @@ -132,18 +132,26 @@ void rt6_age_exceptions(struct fib6_info static inline int ip6_route_get_saddr(struct net *net, struct fib6_info *f6i, const struct in6_addr *daddr, - unsigned int prefs, + unsigned int prefs, int l3mdev_index, struct in6_addr *saddr) { + struct net_device *l3mdev; + struct net_device *dev; + bool same_vrf; int err = 0; - if (f6i && f6i->fib6_prefsrc.plen) { + rcu_read_lock(); + + l3mdev = dev_get_by_index_rcu(net, l3mdev_index); + if (!f6i || !f6i->fib6_prefsrc.plen || l3mdev) + dev = f6i ? fib6_info_nh_dev(f6i) : NULL; + same_vrf = !l3mdev || l3mdev_master_dev_rcu(dev) == l3mdev; + if (f6i && f6i->fib6_prefsrc.plen && same_vrf) *saddr = f6i->fib6_prefsrc.addr; - } else { - struct net_device *dev = f6i ? fib6_info_nh_dev(f6i) : NULL; + else + err = ipv6_dev_get_saddr(net, same_vrf ? dev : l3mdev, daddr, prefs, saddr); - err = ipv6_dev_get_saddr(net, dev, daddr, prefs, saddr); - } + rcu_read_unlock(); return err; } --- a/net/ipv6/ip6_output.c +++ b/net/ipv6/ip6_output.c @@ -1120,6 +1120,7 @@ static int ip6_dst_lookup_tail(struct ne from = rt ? rcu_dereference(rt->from) : NULL; err = ip6_route_get_saddr(net, from, &fl6->daddr, sk ? inet6_sk(sk)->srcprefs : 0, + fl6->flowi6_l3mdev, &fl6->saddr); rcu_read_unlock(); --- a/net/ipv6/route.c +++ b/net/ipv6/route.c @@ -5681,7 +5681,7 @@ static int rt6_fill_node(struct net *net goto nla_put_failure; } else if (dest) { struct in6_addr saddr_buf; - if (ip6_route_get_saddr(net, rt, dest, 0, &saddr_buf) == 0 && + if (ip6_route_get_saddr(net, rt, dest, 0, 0, &saddr_buf) == 0 && nla_put_in6_addr(skb, RTA_PREFSRC, &saddr_buf)) goto nla_put_failure; }