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 C994E7E575; Mon, 8 Apr 2024 13:12:11 +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=1712581931; cv=none; b=mfYY6ct+e8wpvxLSWc+L/8550sTjj7DFa7dXRbZBT8/VOLM3htUph8wqKi57abCKRcAwQhYSK6kv5jIbwtwZmeqsJNi3KSyCuxkfJ3zIf5D1EY/KK4bu/ZGJNUSVAvtbrhnJIeoVwP6L/sMoi3eh77Sn3+Gt30fgxMQeLMR3dq0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712581931; c=relaxed/simple; bh=GlBA0VH/4VOnjX13L9Cx9c8qI9vquKgL1ftP9O5OGpw=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=bi1En7gFpYXo4AEUahrWNn213LpBfCBxLL7J7MdNwE6OPBd5X7/FC5eqHn3ffGx1Q7nUQp2x3dL2jnqS1wBZGE9xdShgkjJGw+3vj3X6K5t5Ehq7rx3XCXP6l13+w2mf0CIsMGDbepmArMU//eF5dZwaECsJggsVHDhy3Fw2O2Y= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=sp9gQvDA; 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="sp9gQvDA" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5116EC433B2; Mon, 8 Apr 2024 13:12:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1712581931; bh=GlBA0VH/4VOnjX13L9Cx9c8qI9vquKgL1ftP9O5OGpw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=sp9gQvDA6dMmTnt8BktJ4Z6phiZYjTikI5xoHQCazdjvO6vzqKnWD30cUPw1e5+kt cDsSihc8WvWMso6Q6oFGvLei76A2qlTfcKV3SxY4qK2cc5aWr8FN6vl3M2eFL7EOo6 3i8iTWr4XGXvyUlMN53B6gA+BzXfHeX1BBr485qg= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Paolo Abeni , Antoine Tenart , Willem de Bruijn , "David S. Miller" Subject: [PATCH 6.1 063/138] udp: prevent local UDP tunnel packets from being GROed Date: Mon, 8 Apr 2024 14:57:57 +0200 Message-ID: <20240408125258.181305031@linuxfoundation.org> X-Mailer: git-send-email 2.44.0 In-Reply-To: <20240408125256.218368873@linuxfoundation.org> References: <20240408125256.218368873@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev 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: Antoine Tenart commit 64235eabc4b5b18c507c08a1f16cdac6c5661220 upstream. GRO has a fundamental issue with UDP tunnel packets as it can't detect those in a foolproof way and GRO could happen before they reach the tunnel endpoint. Previous commits have fixed issues when UDP tunnel packets come from a remote host, but if those packets are issued locally they could run into checksum issues. If the inner packet has a partial checksum the information will be lost in the GRO logic, either in udp4/6_gro_complete or in udp_gro_complete_segment and packets will have an invalid checksum when leaving the host. Prevent local UDP tunnel packets from ever being GROed at the outer UDP level. Due to skb->encapsulation being wrongly used in some drivers this is actually only preventing UDP tunnel packets with a partial checksum to be GROed (see iptunnel_handle_offloads) but those were also the packets triggering issues so in practice this should be sufficient. Fixes: 9fd1ff5d2ac7 ("udp: Support UDP fraglist GRO/GSO.") Fixes: 36707061d6ba ("udp: allow forwarding of plain (non-fraglisted) UDP GRO packets") Suggested-by: Paolo Abeni Signed-off-by: Antoine Tenart Reviewed-by: Willem de Bruijn Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/ipv4/udp_offload.c | 6 ++++++ 1 file changed, 6 insertions(+) --- a/net/ipv4/udp_offload.c +++ b/net/ipv4/udp_offload.c @@ -551,6 +551,12 @@ struct sk_buff *udp_gro_receive(struct l */ NAPI_GRO_CB(skb)->is_flist = 0; if (!sk || !udp_sk(sk)->gro_receive) { + /* If the packet was locally encapsulated in a UDP tunnel that + * wasn't detected above, do not GRO. + */ + if (skb->encapsulation) + goto out; + if (skb->dev->features & NETIF_F_GRO_FRAGLIST) NAPI_GRO_CB(skb)->is_flist = sk ? !udp_test_bit(GRO_ENABLED, sk) : 1;