From nobody Sat Sep 13 18:52:42 2025 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 A1E57C636D4 for ; Tue, 31 Jan 2023 03:47:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230370AbjAaDrA (ORCPT ); Mon, 30 Jan 2023 22:47:00 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56718 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230158AbjAaDq6 (ORCPT ); Mon, 30 Jan 2023 22:46:58 -0500 Received: from gate2.alliedtelesis.co.nz (gate2.alliedtelesis.co.nz [IPv6:2001:df5:b000:5::4]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 61EA41C311 for ; Mon, 30 Jan 2023 19:46:56 -0800 (PST) Received: from svr-chch-seg1.atlnz.lc (mmarshal3.atlnz.lc [10.32.18.43]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) by gate2.alliedtelesis.co.nz (Postfix) with ESMTPS id C88F22C0424; Tue, 31 Jan 2023 16:46:54 +1300 (NZDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=alliedtelesis.co.nz; s=mail181024; t=1675136814; bh=ViLOwDpKVmEvzhrlupzzn+vu78WpKq3y131Y1zeR9Zc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=gPiBCD8Yzj0XgMdY2JsC6thFpP5Y1/znSVCHFcSfs0RvTLN7rQkZnynIJLh0fI1yx 1+FOsA5Pw241Rk6SZbRlA4sNI07u+NY2n5CwhG9GemHYSOq1kYC4IuHeuZGRjqHb77 awGxtbGOeFAe9Tc2FGJOJcoIt7ISovKtv9lOiGEI6MJ8GDGicRJrhQDp4fkhqQI6qj aSmEJzhRLnao49wquq0Ch+qrBQoNljw0Ws90aFlvU4319C0KBm2j97UN7JXKd1zbKs AttAt4Yc/bGD9adfeSg/I9VkHSnAzI52UYrOSGHg7VrFZCiQgdHsnYVTBIqaLMMqp4 dbgsC6GsaePiA== Received: from pat.atlnz.lc (Not Verified[10.32.16.33]) by svr-chch-seg1.atlnz.lc with Trustwave SEG (v8,2,6,11305) id ; Tue, 31 Jan 2023 16:46:54 +1300 Received: from thomaswi-dl.ws.atlnz.lc (thomaswi-dl.ws.atlnz.lc [10.33.25.46]) by pat.atlnz.lc (Postfix) with ESMTP id 7718613EE3F; Tue, 31 Jan 2023 16:46:54 +1300 (NZDT) Received: by thomaswi-dl.ws.atlnz.lc (Postfix, from userid 1719) id 75A213E089B; Tue, 31 Jan 2023 16:46:54 +1300 (NZDT) From: Thomas Winter To: davem@davemloft.net, yoshfuji@linux-ipv6.org, dsahern@kernel.org, pabeni@redhat.com, edumazet@google.com, kuba@kernel.org, a@unstable.cc, netdev@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Thomas Winter Subject: [PATCH v5 1/2] ip/ip6_gre: Fix changing addr gen mode not generating IPv6 link local address Date: Tue, 31 Jan 2023 16:46:45 +1300 Message-Id: <20230131034646.237671-2-Thomas.Winter@alliedtelesis.co.nz> X-Mailer: git-send-email 2.39.0 In-Reply-To: <20230131034646.237671-1-Thomas.Winter@alliedtelesis.co.nz> References: <20230131034646.237671-1-Thomas.Winter@alliedtelesis.co.nz> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-SEG-SpamProfiler-Analysis: v=2.3 cv=a6lOCnaF c=1 sm=1 tr=0 a=KLBiSEs5mFS1a/PbTCJxuA==:117 a=RvmDmJFTN0MA:10 a=RPFMgMUpu3LH_QEMZcEA:9 X-SEG-SpamProfiler-Score: 0 x-atlnz-ls: pat Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" For our point-to-point GRE tunnels, they have IN6_ADDR_GEN_MODE_NONE when they are created then we set IN6_ADDR_GEN_MODE_EUI64 when they come up to generate the IPv6 link local address for the interface. Recently we found that they were no longer generating IPv6 addresses. This issue would also have affected SIT tunnels. Commit e5dd729460ca changed the code path so that GRE tunnels generate an IPv6 address based on the tunnel source address. It also changed the code path so GRE tunnels don't call addrconf_addr_gen in addrconf_dev_config which is called by addrconf_sysctl_addr_gen_mode when the IN6_ADDR_GEN_MODE is changed. This patch aims to fix this issue by moving the code in addrconf_notify which calls the addr gen for GRE and SIT into a separate function and calling it in the places that expect the IPv6 address to be generated. The previous addrconf_dev_config is renamed to addrconf_eth_config since it only expected eth type interfaces and follows the addrconf_gre/sit_config format. A part of this changes means that the loopback address will be attempted to be configured when changing addr_gen_mode for lo. This should not be a problem because the address should exist anyway and if does already exist then no error is produced. Fixes: e5dd729460ca ("ip/ip6_gre: use the same logic as SIT interfaces when= computing v6LL address") Signed-off-by: Thomas Winter Reviewed-by: David Ahern --- net/ipv6/addrconf.c | 49 +++++++++++++++++++++++++-------------------- 1 file changed, 27 insertions(+), 22 deletions(-) diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c index f7a84a4acffc..f4ba68e096ac 100644 --- a/net/ipv6/addrconf.c +++ b/net/ipv6/addrconf.c @@ -3447,6 +3447,30 @@ static void addrconf_gre_config(struct net_device *d= ev) } #endif =20 +static void addrconf_init_auto_addrs(struct net_device *dev) +{ + switch (dev->type) { +#if IS_ENABLED(CONFIG_IPV6_SIT) + case ARPHRD_SIT: + addrconf_sit_config(dev); + break; +#endif +#if IS_ENABLED(CONFIG_NET_IPGRE) || IS_ENABLED(CONFIG_IPV6_GRE) + case ARPHRD_IP6GRE: + case ARPHRD_IPGRE: + addrconf_gre_config(dev); + break; +#endif + case ARPHRD_LOOPBACK: + init_loopback(dev); + break; + + default: + addrconf_dev_config(dev); + break; + } +} + static int fixup_permanent_addr(struct net *net, struct inet6_dev *idev, struct inet6_ifaddr *ifp) @@ -3615,26 +3639,7 @@ static int addrconf_notify(struct notifier_block *th= is, unsigned long event, run_pending =3D 1; } =20 - switch (dev->type) { -#if IS_ENABLED(CONFIG_IPV6_SIT) - case ARPHRD_SIT: - addrconf_sit_config(dev); - break; -#endif -#if IS_ENABLED(CONFIG_NET_IPGRE) || IS_ENABLED(CONFIG_IPV6_GRE) - case ARPHRD_IP6GRE: - case ARPHRD_IPGRE: - addrconf_gre_config(dev); - break; -#endif - case ARPHRD_LOOPBACK: - init_loopback(dev); - break; - - default: - addrconf_dev_config(dev); - break; - } + addrconf_init_auto_addrs(dev); =20 if (!IS_ERR_OR_NULL(idev)) { if (run_pending) @@ -6397,7 +6402,7 @@ static int addrconf_sysctl_addr_gen_mode(struct ctl_t= able *ctl, int write, =20 if (idev->cnf.addr_gen_mode !=3D new_val) { idev->cnf.addr_gen_mode =3D new_val; - addrconf_dev_config(idev->dev); + addrconf_init_auto_addrs(idev->dev); } } else if (&net->ipv6.devconf_all->addr_gen_mode =3D=3D ctl->data) { struct net_device *dev; @@ -6408,7 +6413,7 @@ static int addrconf_sysctl_addr_gen_mode(struct ctl_t= able *ctl, int write, if (idev && idev->cnf.addr_gen_mode !=3D new_val) { idev->cnf.addr_gen_mode =3D new_val; - addrconf_dev_config(idev->dev); + addrconf_init_auto_addrs(idev->dev); } } } --=20 2.39.0 From nobody Sat Sep 13 18:52:42 2025 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 05DCAC38142 for ; Tue, 31 Jan 2023 03:47:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230430AbjAaDrG (ORCPT ); Mon, 30 Jan 2023 22:47:06 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56732 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230272AbjAaDq7 (ORCPT ); Mon, 30 Jan 2023 22:46:59 -0500 Received: from gate2.alliedtelesis.co.nz (gate2.alliedtelesis.co.nz [IPv6:2001:df5:b000:5::4]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 19ED3EFBF for ; Mon, 30 Jan 2023 19:46:58 -0800 (PST) Received: from svr-chch-seg1.atlnz.lc (mmarshal3.atlnz.lc [10.32.18.43]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) by gate2.alliedtelesis.co.nz (Postfix) with ESMTPS id BED6E2C0108; 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Tue, 31 Jan 2023 16:46:54 +1300 (NZDT) From: Thomas Winter To: davem@davemloft.net, yoshfuji@linux-ipv6.org, dsahern@kernel.org, pabeni@redhat.com, edumazet@google.com, kuba@kernel.org, a@unstable.cc, netdev@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Thomas Winter Subject: [PATCH v5 2/2] ip/ip6_gre: Fix non-point-to-point tunnel not generating IPv6 link local address Date: Tue, 31 Jan 2023 16:46:46 +1300 Message-Id: <20230131034646.237671-3-Thomas.Winter@alliedtelesis.co.nz> X-Mailer: git-send-email 2.39.0 In-Reply-To: <20230131034646.237671-1-Thomas.Winter@alliedtelesis.co.nz> References: <20230131034646.237671-1-Thomas.Winter@alliedtelesis.co.nz> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-SEG-SpamProfiler-Analysis: v=2.3 cv=a6lOCnaF c=1 sm=1 tr=0 a=KLBiSEs5mFS1a/PbTCJxuA==:117 a=RvmDmJFTN0MA:10 a=grpyvFInbdX5ElKdMEcA:9 X-SEG-SpamProfiler-Score: 0 x-atlnz-ls: pat Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" We recently found that our non-point-to-point tunnels were not generating any IPv6 link local address and instead generating an IPv6 compat address, breaking IPv6 communication on the tunnel. Previously, addrconf_gre_config always would call addrconf_addr_gen and generate a EUI64 link local address for the tunnel. Then commit e5dd729460ca changed the code path so that add_v4_addrs is called but this only generates a compat IPv6 address for non-point-to-point tunnels. I assume the compat address is specifically for SIT tunnels so have kept that only for SIT - GRE tunnels now always generate link local addresses. Fixes: e5dd729460ca ("ip/ip6_gre: use the same logic as SIT interfaces when= computing v6LL address") Signed-off-by: Thomas Winter --- net/ipv6/addrconf.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c index f4ba68e096ac..faa47f9ea73a 100644 --- a/net/ipv6/addrconf.c +++ b/net/ipv6/addrconf.c @@ -3127,17 +3127,17 @@ static void add_v4_addrs(struct inet6_dev *idev) offset =3D sizeof(struct in6_addr) - 4; memcpy(&addr.s6_addr32[3], idev->dev->dev_addr + offset, 4); =20 - if (idev->dev->flags&IFF_POINTOPOINT) { + if (!(idev->dev->flags & IFF_POINTOPOINT) && idev->dev->type =3D=3D ARPHR= D_SIT) { + scope =3D IPV6_ADDR_COMPATv4; + plen =3D 96; + pflags |=3D RTF_NONEXTHOP; + } else { if (idev->cnf.addr_gen_mode =3D=3D IN6_ADDR_GEN_MODE_NONE) return; =20 addr.s6_addr32[0] =3D htonl(0xfe800000); scope =3D IFA_LINK; plen =3D 64; - } else { - scope =3D IPV6_ADDR_COMPATv4; - plen =3D 96; - pflags |=3D RTF_NONEXTHOP; } =20 if (addr.s6_addr32[3]) { --=20 2.39.0