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 0FAA12EA49C; Tue, 15 Jul 2025 13:40:36 +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=1752586836; cv=none; b=rKmk2qKb47AOemcb/TSZeE06GftMpiwtorgMiWhYLGzgBMhOsS/7XpysX+pEwkulLNrnldVLmc8WM/A1sfxwYEFedA0YHRGmJl122uv0f5YaHuvHINZEOSHeOR8IQyTZ5iOHZ76YEvquVuFTI5WR4Rd4oqjAZDrGxhhiHb2WdSo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1752586836; c=relaxed/simple; bh=wg+dlCNc3yovJ4uBRPNQ/z6oo1OkwKCW65dKxMst+RQ=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=XAvdPfSIRpJ7Fi/c99ljZSKARvco6Epei8IKm2ZAPUz7dV+QfzlVPkUXTaLPj3gt2RAxRdS6PfFcwCpR3BVbFIL7iBSWYTCMzNBjUtaAhXAa3vp10dt6QYvmqJrHcPy3G3DM6j9ZhCLeiJxWhmTC3KvmdOxvx707cPJUNZsglMc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=uvvzX2+u; 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="uvvzX2+u" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6FCAFC4CEE3; Tue, 15 Jul 2025 13:40:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1752586835; bh=wg+dlCNc3yovJ4uBRPNQ/z6oo1OkwKCW65dKxMst+RQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=uvvzX2+uKxER33AjsaySHQ9Ihnatx31pz6pOrLDgsKX36Bc+czz3lg2X74mq+nd3Q XtyRozATCbENws1MZLRNQ1qTkBgI77pjmjP1/BoduSTQ91kdtX4H5pEZISBgvSFcog oBMeWoMGzPjmcTf0TXvGB2YMkyu0w3GTB+7sl7L8= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Aiden Yang , Gary Guo , Guillaume Nault , Ido Schimmel , Jakub Kicinski Subject: [PATCH 6.15 067/192] gre: Fix IPv6 multicast route creation. Date: Tue, 15 Jul 2025 15:12:42 +0200 Message-ID: <20250715130817.627318973@linuxfoundation.org> X-Mailer: git-send-email 2.50.1 In-Reply-To: <20250715130814.854109770@linuxfoundation.org> References: <20250715130814.854109770@linuxfoundation.org> User-Agent: quilt/0.68 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 6.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Guillaume Nault commit 4e914ef063de40397e25a025c70d9737a9e45a8c upstream. Use addrconf_add_dev() instead of ipv6_find_idev() in addrconf_gre_config() so that we don't just get the inet6_dev, but also install the default ff00::/8 multicast route. Before commit 3e6a0243ff00 ("gre: Fix again IPv6 link-local address generation."), the multicast route was created at the end of the function by addrconf_add_mroute(). But this code path is now only taken in one particular case (gre devices not bound to a local IP address and in EUI64 mode). For all other cases, the function exits early and addrconf_add_mroute() is not called anymore. Using addrconf_add_dev() instead of ipv6_find_idev() in addrconf_gre_config(), fixes the problem as it will create the default multicast route for all gre devices. This also brings addrconf_gre_config() a bit closer to the normal netdevice IPv6 configuration code (addrconf_dev_config()). Cc: stable@vger.kernel.org Fixes: 3e6a0243ff00 ("gre: Fix again IPv6 link-local address generation.") Reported-by: Aiden Yang Closes: https://lore.kernel.org/netdev/CANR=AhRM7YHHXVxJ4DmrTNMeuEOY87K2mLmo9KMed1JMr20p6g@mail.gmail.com/ Reviewed-by: Gary Guo Tested-by: Gary Guo Signed-off-by: Guillaume Nault Reviewed-by: Ido Schimmel Link: https://patch.msgid.link/027a923dcb550ad115e6d93ee8bb7d310378bd01.1752070620.git.gnault@redhat.com Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman --- net/ipv6/addrconf.c | 9 ++------- 1 file changed, 2 insertions(+), 7 deletions(-) --- a/net/ipv6/addrconf.c +++ b/net/ipv6/addrconf.c @@ -3525,11 +3525,9 @@ static void addrconf_gre_config(struct n ASSERT_RTNL(); - idev = ipv6_find_idev(dev); - if (IS_ERR(idev)) { - pr_debug("%s: add_dev failed\n", __func__); + idev = addrconf_add_dev(dev); + if (IS_ERR(idev)) return; - } /* Generate the IPv6 link-local address using addrconf_addr_gen(), * unless we have an IPv4 GRE device not bound to an IP address and @@ -3543,9 +3541,6 @@ static void addrconf_gre_config(struct n } add_v4_addrs(idev); - - if (dev->flags & IFF_POINTOPOINT) - addrconf_add_mroute(dev); } #endif