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 22BAA2D73A0; Thu, 15 Jan 2026 17:03:29 +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=1768496609; cv=none; b=rQKRUH76dGUcgh/Cf8suYAHSTWY1uBiVIDK7wthNPc8og2+F6s6u/gx9bKWfp9YHSu6O4HareaJQmMbwdRKPExuecUBu/v0QW2pNohAIFx0OhHjuXx9RVpJLg0VI7PiUaa3HrQXqI92xFrGJ7rWCOFUm5ZT619VLaYrBQhLejaA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768496609; c=relaxed/simple; bh=gYiDYe8cSfBeCI/meXJthw+n/NQf4+S2pDAftkbTgB4=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=fuGuaKp8F6p6uX+1vMkaH8Iv8jreOppJr9mAhWGdyspV9AZunUZ0AmbmyXI7yawv5A2kABa9i1cbPitISmG0fXqGmU6pW+zLO5UZjB3OV19SO62nWarz60QPE2zhs38FuuBWLJvwyQBV4f4eZzLkzDb2bFjW8S976sw2HmTo7ts= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=qkV+CJcV; 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="qkV+CJcV" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 93C09C116D0; Thu, 15 Jan 2026 17:03:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1768496609; bh=gYiDYe8cSfBeCI/meXJthw+n/NQf4+S2pDAftkbTgB4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=qkV+CJcV2DNa/IJTZD9JqVRnEHpCKjMkSJY7qFLzKXZ4te6DSpeJl4nx0Fns+5tgD 9vmBHoK/WnDr/8kNBICrpoPWIpxgYq0jNto8Kw4ANCIt9In3K+SuluAVE1jmIe49jd yQBfjw4EtzuUcDrohu05AGrbHqt5OO3LIaxAkc7g= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Alexandre Knecht , Ido Schimmel , Nikolay Aleksandrov , Jakub Kicinski , Sasha Levin Subject: [PATCH 6.12 065/119] bridge: fix C-VLAN preservation in 802.1ad vlan_tunnel egress Date: Thu, 15 Jan 2026 17:48:00 +0100 Message-ID: <20260115164154.301208098@linuxfoundation.org> X-Mailer: git-send-email 2.52.0 In-Reply-To: <20260115164151.948839306@linuxfoundation.org> References: <20260115164151.948839306@linuxfoundation.org> User-Agent: quilt/0.69 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 6.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Alexandre Knecht [ Upstream commit 3128df6be147768fe536986fbb85db1d37806a9f ] When using an 802.1ad bridge with vlan_tunnel, the C-VLAN tag is incorrectly stripped from frames during egress processing. br_handle_egress_vlan_tunnel() uses skb_vlan_pop() to remove the S-VLAN from hwaccel before VXLAN encapsulation. However, skb_vlan_pop() also moves any "next" VLAN from the payload into hwaccel: /* move next vlan tag to hw accel tag */ __skb_vlan_pop(skb, &vlan_tci); __vlan_hwaccel_put_tag(skb, vlan_proto, vlan_tci); For QinQ frames where the C-VLAN sits in the payload, this moves it to hwaccel where it gets lost during VXLAN encapsulation. Fix by calling __vlan_hwaccel_clear_tag() directly, which clears only the hwaccel S-VLAN and leaves the payload untouched. This path is only taken when vlan_tunnel is enabled and tunnel_info is configured, so 802.1Q bridges are unaffected. Tested with 802.1ad bridge + VXLAN vlan_tunnel, verified C-VLAN preserved in VXLAN payload via tcpdump. Fixes: 11538d039ac6 ("bridge: vlan dst_metadata hooks in ingress and egress paths") Signed-off-by: Alexandre Knecht Reviewed-by: Ido Schimmel Acked-by: Nikolay Aleksandrov Link: https://patch.msgid.link/20251228020057.2788865-1-knecht.alexandre@gmail.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- net/bridge/br_vlan_tunnel.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) diff --git a/net/bridge/br_vlan_tunnel.c b/net/bridge/br_vlan_tunnel.c index a966a6ec82634..257cae9f15698 100644 --- a/net/bridge/br_vlan_tunnel.c +++ b/net/bridge/br_vlan_tunnel.c @@ -189,7 +189,6 @@ int br_handle_egress_vlan_tunnel(struct sk_buff *skb, IP_TUNNEL_DECLARE_FLAGS(flags) = { }; struct metadata_dst *tunnel_dst; __be64 tunnel_id; - int err; if (!vlan) return 0; @@ -199,9 +198,13 @@ int br_handle_egress_vlan_tunnel(struct sk_buff *skb, return 0; skb_dst_drop(skb); - err = skb_vlan_pop(skb); - if (err) - return err; + /* For 802.1ad (QinQ), skb_vlan_pop() incorrectly moves the C-VLAN + * from payload to hwaccel after clearing S-VLAN. We only need to + * clear the hwaccel S-VLAN; the C-VLAN must stay in payload for + * correct VXLAN encapsulation. This is also correct for 802.1Q + * where no C-VLAN exists in payload. + */ + __vlan_hwaccel_clear_tag(skb); if (BR_INPUT_SKB_CB(skb)->backup_nhid) { __set_bit(IP_TUNNEL_KEY_BIT, flags); -- 2.51.0