Commit 7be49d24 authored by David S. Miller's avatar David S. Miller
Browse files

Merge branch 'SO_MARK-routing' 



Jakub Kicinski says:

====================
udp6: allow SO_MARK ctrl msg to affect routing

Looks like SO_MARK from cmsg does not affect routing policy.
This seems accidental.

I opted for net because of the discrepancy between IPv4
and IPv6, but it never worked and doesn't cause crashes..
====================

Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parents 6de6e46d b0ced8f2

net/ipv6/udp.c

+1 −1
Original line number Diff line number Diff line
@@ -1435,7 +1435,6 @@ int udpv6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len) 
	if (!fl6.flowi6_oif)

		fl6.flowi6_oif = np->sticky_pktinfo.ipi6_ifindex;



	fl6.flowi6_mark = ipc6.sockc.mark;

	fl6.flowi6_uid = sk->sk_uid;



	if (msg->msg_controllen) {
@@ -1471,6 +1470,7 @@ int udpv6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len) 
	ipc6.opt = opt;



	fl6.flowi6_proto = sk->sk_protocol;

	fl6.flowi6_mark = ipc6.sockc.mark;

	fl6.daddr = *daddr;

	if (ipv6_addr_any(&fl6.saddr) && !ipv6_addr_any(&np->saddr))

		fl6.saddr = np->saddr;

tools/testing/selftests/net/.gitignore

+1 −0
Original line number Diff line number Diff line
@@ -35,3 +35,4 @@ test_unix_oob 
gro

ioam6_parser

toeplitz

cmsg_so_mark

tools/testing/selftests/net/Makefile

+2 −0
Original line number Diff line number Diff line
@@ -28,6 +28,7 @@ TEST_PROGS += veth.sh 
TEST_PROGS += ioam6.sh

TEST_PROGS += gro.sh

TEST_PROGS += gre_gso.sh

TEST_PROGS += cmsg_so_mark.sh

TEST_PROGS_EXTENDED := in_netns.sh

TEST_GEN_FILES =  socket nettest

TEST_GEN_FILES += psock_fanout psock_tpacket msg_zerocopy reuseport_addr_any
@@ -44,6 +45,7 @@ TEST_GEN_FILES += gro 
TEST_GEN_PROGS = reuseport_bpf reuseport_bpf_cpu reuseport_bpf_numa

TEST_GEN_PROGS += reuseport_dualstack reuseaddr_conflict tls

TEST_GEN_FILES += toeplitz

TEST_GEN_FILES += cmsg_so_mark



TEST_FILES := settings

tools/testing/selftests/net/cmsg_so_mark.c

0 → 100644
+67 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0-or-later

#include <errno.h>

#include <netdb.h>

#include <stdio.h>

#include <stdlib.h>

#include <string.h>

#include <unistd.h>

#include <linux/types.h>

#include <sys/socket.h>



int main(int argc, const char **argv)

{

	char cbuf[CMSG_SPACE(sizeof(__u32))];

	struct addrinfo hints, *ai;

	struct cmsghdr *cmsg;

	struct iovec iov[1];

	struct msghdr msg;

	int mark;

	int err;

	int fd;



	if (argc != 4) {

		fprintf(stderr, "Usage: %s <dst_ip> <port> <mark>\n", argv[0]);

		return 1;

	}

	mark = atoi(argv[3]);



	memset(&hints, 0, sizeof(hints));

	hints.ai_family = AF_UNSPEC;

	hints.ai_socktype = SOCK_DGRAM;



	ai = NULL;

	err = getaddrinfo(argv[1], argv[2], &hints, &ai);

	if (err) {

		fprintf(stderr, "Can't resolve address: %s\n", strerror(errno));

		return 1;

	}



	fd = socket(ai->ai_family, SOCK_DGRAM, IPPROTO_UDP);

	if (fd < 0) {

		fprintf(stderr, "Can't open socket: %s\n", strerror(errno));

		freeaddrinfo(ai);

		return 1;

	}



	iov[0].iov_base = "bla";

	iov[0].iov_len = 4;



	msg.msg_name = ai->ai_addr;

	msg.msg_namelen = ai->ai_addrlen;

	msg.msg_iov = iov;

	msg.msg_iovlen = 1;

	msg.msg_control = cbuf;

	msg.msg_controllen = sizeof(cbuf);



	cmsg = CMSG_FIRSTHDR(&msg);

	cmsg->cmsg_level = SOL_SOCKET;

	cmsg->cmsg_type = SO_MARK;

	cmsg->cmsg_len = CMSG_LEN(sizeof(__u32));

	*(__u32 *)CMSG_DATA(cmsg) = mark;



	err = sendmsg(fd, &msg, 0);



	close(fd);

	freeaddrinfo(ai);

	return err != 4;

}

tools/testing/selftests/net/cmsg_so_mark.sh

0 → 100755
+61 −0
Original line number Diff line number Diff line 
#!/bin/bash

# SPDX-License-Identifier: GPL-2.0



NS=ns

IP4=172.16.0.1/24

TGT4=172.16.0.2

IP6=2001:db8:1::1/64

TGT6=2001:db8:1::2

MARK=1000



cleanup()

{

    ip netns del $NS

}



trap cleanup EXIT



# Namespaces

ip netns add $NS



# Connectivity

ip -netns $NS link add type dummy

ip -netns $NS link set dev dummy0 up

ip -netns $NS addr add $IP4 dev dummy0

ip -netns $NS addr add $IP6 dev dummy0



ip -netns $NS rule add fwmark $MARK lookup 300

ip -6 -netns $NS rule add fwmark $MARK lookup 300

ip -netns $NS route add prohibit any table 300

ip -6 -netns $NS route add prohibit any table 300



# Test

BAD=0

TOTAL=0



check_result() {

    ((TOTAL++))

    if [ $1 -ne $2 ]; then

	echo "  Case $3 returned $1, expected $2"

	((BAD++))

    fi

}



ip netns exec $NS ./cmsg_so_mark $TGT4 1234 $((MARK + 1))

check_result $? 0 "IPv4 pass"

ip netns exec $NS ./cmsg_so_mark $TGT6 1234 $((MARK + 1))

check_result $? 0 "IPv6 pass"



ip netns exec $NS ./cmsg_so_mark $TGT4 1234 $MARK

check_result $? 1 "IPv4 rejection"

ip netns exec $NS ./cmsg_so_mark $TGT6 1234 $MARK

check_result $? 1 "IPv6 rejection"



# Summary

if [ $BAD -ne 0 ]; then

    echo "FAIL - $BAD/$TOTAL cases failed"

    exit 1

else

    echo "OK"

    exit 0

fi