From patchwork Mon Feb 24 13:25:50 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Anton Ivanov X-Patchwork-Id: 1243082 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=none (no SPF record) smtp.mailfrom=lists.infradead.org (client-ip=2607:7c80:54:e::133; helo=bombadil.infradead.org; envelope-from=linux-um-bounces+incoming=patchwork.ozlabs.org@lists.infradead.org; receiver=) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=cambridgegreys.com Authentication-Results: ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=lists.infradead.org header.i=@lists.infradead.org header.a=rsa-sha256 header.s=bombadil.20170209 header.b=kuPISurK; dkim-atps=neutral Received: from bombadil.infradead.org (bombadil.infradead.org [IPv6:2607:7c80:54:e::133]) (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) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 48R2rt2RJCz9sPk for ; Tue, 25 Feb 2020 00:26:22 +1100 (AEDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:Message-Id:Date:Subject:To :From:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To:References: List-Owner; bh=WsTqLT916YB7YtFqsNEc3u1ZPrmYqWeXNNeW0V0QZGY=; b=kuPISurKNDCeJj s9NeX26UlxYE7kyTziVY4XC3IDZCE+EW1LrGtezutffIOGiEDhj8LSrVPEtfI8w1YjJmrWLIUK1h3 5YUOCM6cmgrhn14LCJO2lEhuRsezOdLExSKtLxrf5c7syBsK4bOokq3xHAsu3koOpSclvoRd644C8 g2iSNIEML7D2YlvmqKyoHCj5bOyTz/XvOh2T7rw08Z8al90FiNXZZjqIvmv6TJweKaPk8W1oljiJi WqIIx7Jv6m2v/OGfQKLeiQcX2ogwscLgJYyx8Gbj3F2xoTAuunMfCh67X8X7LTk6KPkCJSYUQgMba JrtEOgvTKMO2C6OkA8uw==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1j6DkS-0004Ln-Tx; Mon, 24 Feb 2020 13:26:12 +0000 Received: from ivanoab7.miniserver.com ([37.128.132.42] helo=www.kot-begemot.co.uk) by bombadil.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1j6DkQ-0004LG-4D for linux-um@lists.infradead.org; Mon, 24 Feb 2020 13:26:11 +0000 Received: from tun252.jain.kot-begemot.co.uk ([192.168.18.6] helo=jain.kot-begemot.co.uk) by www.kot-begemot.co.uk with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1j6DkI-0005jE-6t; Mon, 24 Feb 2020 13:26:06 +0000 Received: from jain.kot-begemot.co.uk ([192.168.3.3]) by jain.kot-begemot.co.uk with esmtp (Exim 4.92) (envelope-from ) id 1j6Dk9-0000Yj-0t; Mon, 24 Feb 2020 13:25:57 +0000 From: anton.ivanov@cambridgegreys.com To: netdev@vger.kernel.org, virtualization@lists.linux-foundation.org, linux-um@lists.infradead.org Subject: [PATCH v3] virtio: Work around frames incorrectly marked as gso Date: Mon, 24 Feb 2020 13:25:50 +0000 Message-Id: <20200224132550.2083-1-anton.ivanov@cambridgegreys.com> X-Mailer: git-send-email 2.20.1 MIME-Version: 1.0 X-Spam-Score: -1.0 X-Spam-Score: -1.0 X-Clacks-Overhead: GNU Terry Pratchett X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200224_052610_169292_8CBD6EF4 X-CRM114-Status: GOOD ( 10.29 ) X-Spam-Score: 0.4 (/) X-Spam-Report: SpamAssassin version 3.4.3 on bombadil.infradead.org summary: Content analysis details: (0.4 points) pts rule name description ---- ---------------------- -------------------------------------------------- 0.0 SPF_HELO_NONE SPF: HELO does not publish an SPF Record 0.0 SPF_NONE SPF: sender does not publish an SPF Record 0.4 KHOP_HELO_FCRDNS Relay HELO differs from its IP's reverse DNS X-BeenThere: linux-um@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: jasowang@redhat.com, Anton Ivanov , eric.dumazet@gmail.com, mst@redhat.com Sender: "linux-um" Errors-To: linux-um-bounces+incoming=patchwork.ozlabs.org@lists.infradead.org From: Anton Ivanov Some of the locally generated frames marked as GSO which arrive at virtio_net_hdr_from_skb() have no GSO_TYPE, no fragments (data_len = 0) and length significantly shorter than the MTU (752 in my experiments). This is observed on raw sockets reading off vEth interfaces in all 4.x and 5.x kernels. The frames are reported as invalid, while they are in fact gso-less frames. The easiest way to reproduce is to connect a User Mode Linux instance to the host using the vector raw transport and a vEth interface. Vector raw uses recvmmsg/sendmmsg with virtio headers on af_packet sockets. When running iperf between the UML and the host, UML regularly complains about EINVAL return from recvmmsg. This patch marks the vnet header as non-GSO instead of reporting it as invalid. Signed-off-by: Anton Ivanov Reviewed-by: Michael S. Tsirkin --- include/linux/virtio_net.h | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/include/linux/virtio_net.h b/include/linux/virtio_net.h index 0d1fe9297ac6..2c99c752cb20 100644 --- a/include/linux/virtio_net.h +++ b/include/linux/virtio_net.h @@ -98,10 +98,11 @@ static inline int virtio_net_hdr_from_skb(const struct sk_buff *skb, bool has_data_valid, int vlan_hlen) { + struct skb_shared_info *sinfo = skb_shinfo(skb); + memset(hdr, 0, sizeof(*hdr)); /* no info leak */ - if (skb_is_gso(skb)) { - struct skb_shared_info *sinfo = skb_shinfo(skb); + if (skb_is_gso(skb) && sinfo->gso_type) { /* This is a hint as to how much should be linear. */ hdr->hdr_len = __cpu_to_virtio16(little_endian,