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 1AE0A3E959F; Thu, 15 Jan 2026 18:00:32 +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=1768500032; cv=none; b=Rp33UiC5sz/ZaKVdWQZSca4CBJ2AiaoXyjFdurzZH+TWaiQOQm5N84TZCH6IaKU/6l1+IC1mp0u419CuqzpjCN5KQH/tdjr1Jb2VpSUtffQSzMSCoCcH6IsHheiWqEP2syXk0i00VSfwoznLdb4cOsbX+lnqsjbIToi8VfY8QL4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768500032; c=relaxed/simple; bh=L5VmHjg/1CtPEXItYS9L1IrSVW12gm0dUokX8g9LE/k=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=KyT2f1mL6RQDAhdukxw5ncNyl3wgQvqfyAP2FWdo5fhBaBBR9omIjPTlpF/AIeJJ8WDFQJmQHTK4EK6BwS7bocffld8qI8rpHoeX7sTq3J6FcAxQOaGdOb4DRkQ5B56txDcRCPwDB2RjyxqPDJn3Lu+7xfUUkSPAqAmqwXL61Yw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=DKYCTKzv; 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="DKYCTKzv" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 953FAC116D0; Thu, 15 Jan 2026 18:00:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1768500032; bh=L5VmHjg/1CtPEXItYS9L1IrSVW12gm0dUokX8g9LE/k=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=DKYCTKzvhaXxGdqiEU0TNe7Zds6z5bD2MLH567g5l8IIi6ijGFPcS68FKjX1ujrMD bvuhuQryduUeZMuKd+/TA3OZzxZYlOLpx4LKBs8zLyB4ouV/zjFUeuiB/qIqbHP9i5 WNnKd7I7n3kSW/v62jEsKp7VXV8pSXhn6usM6M+8= 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 5.10 434/451] bridge: fix C-VLAN preservation in 802.1ad vlan_tunnel egress Date: Thu, 15 Jan 2026 17:50:35 +0100 Message-ID: <20260115164246.647623913@linuxfoundation.org> X-Mailer: git-send-email 2.52.0 In-Reply-To: <20260115164230.864985076@linuxfoundation.org> References: <20260115164230.864985076@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 5.10-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 debe167202782..9e960e2ab3fa9 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, { 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); tunnel_dst = rcu_dereference(vlan->tinfo.tunnel_dst); if (tunnel_dst && dst_hold_safe(&tunnel_dst->dst)) -- 2.51.0