Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Organization: Red Hat UK Ltd. Registered Address: Red Hat UK Ltd, Amberley
        Place, 107-111 Peascod Street, Windsor, Berkshire, SI4 1TE, United
        Kingdom.
        Registered in England and Wales under Company Registration No. 3798903
Subject: [PATCH] rxrpc: Enable IPv6 checksums on transport socket
From:   David Howells <dhowells@redhat.com>
To:     marc.dionne@auristor.com
Cc:     Xin Long <lucien.xin@gmail.com>,
        Vadim Fedorenko <vfedorenko@novek.ru>,
        "David S. Miller" <davem@davemloft.net>,
        linux-afs@lists.infradead.org, dhowells@redhat.com,
        linux-kernel@vger.kernel.org
Date:   Wed, 27 Apr 2022 22:30:36 +0100
Message-ID: <165109503652.611257.12851860419631266883.stgit@warthog.procyon.org.uk>
User-Agent: StGit/1.4
MIME-Version: 1.0
Content-Type: text/plain; charset="utf-8"
Content-Transfer-Encoding: 7bit
Precedence: bulk

AF_RXRPC doesn't currently enable IPv6 UDP Tx checksums on the transport
socket it opens and the checksums in the packets it generates end up 0.

It probably should also enable IPv6 UDP Rx checksums and IPv4 UDP
checksums.  The latter only seem to be applied if the socket family is
AF_INET and don't seem to apply if it's AF_INET6.  IPv4 packets from an
IPv6 socket seem to have checksums anyway.

What seems to have happened is that the inet_inv_convert_csum() call didn't
get converted to the appropriate udp_port_cfg parameters - and
udp_sock_create() disables checksums unless explicitly told not too.

Fix this by enabling the three udp_port_cfg checksum options.

Fixes: 1a9b86c9fd95 ("rxrpc: use udp tunnel APIs instead of open code in rxrpc_open_socket")
Reported-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Xin Long <lucien.xin@gmail.com>
cc: Vadim Fedorenko <vfedorenko@novek.ru>
cc: David S. Miller <davem@davemloft.net>
cc: linux-afs@lists.infradead.org
---

 net/rxrpc/local_object.c |    3 +++
 1 file changed, 3 insertions(+)

diff --git a/net/rxrpc/local_object.c b/net/rxrpc/local_object.c
index a4111408ffd0..6a1611b0e303 100644
--- a/net/rxrpc/local_object.c
+++ b/net/rxrpc/local_object.c
@@ -117,6 +117,7 @@ static int rxrpc_open_socket(struct rxrpc_local *local, struct net *net)
 	       local, srx->transport_type, srx->transport.family);
 
 	udp_conf.family = srx->transport.family;
+	udp_conf.use_udp_checksums = true;
 	if (udp_conf.family == AF_INET) {
 		udp_conf.local_ip = srx->transport.sin.sin_addr;
 		udp_conf.local_udp_port = srx->transport.sin.sin_port;
@@ -124,6 +125,8 @@ static int rxrpc_open_socket(struct rxrpc_local *local, struct net *net)
 	} else {
 		udp_conf.local_ip6 = srx->transport.sin6.sin6_addr;
 		udp_conf.local_udp_port = srx->transport.sin6.sin6_port;
+		udp_conf.use_udp6_tx_checksums = true;
+		udp_conf.use_udp6_rx_checksums = true;
 #endif
 	}
 	ret = udp_sock_create(net, &udp_conf, &local->socket);