Linux kernel mirror (for testing) git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel os linux

net: netconsole: selftests: Create a new netconsole selftest

Adds a selftest that creates two virtual interfaces, assigns one to a
new namespace, and assigns IP addresses to both.

It listens on the destination interface using socat and configures a
dynamic target on netconsole, pointing to the destination IP address.

The test then checks if the message was received properly on the
destination interface.

Signed-off-by: Breno Leitao <leitao@debian.org>
Acked-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://patch.msgid.link/20240822095652.3806208-1-leitao@debian.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

authored by

Breno Leitao and committed by
Jakub Kicinski
b494b167 9f08ae4f

+243 -1
+1
MAINTAINERS
··· 15775 15775 S: Maintained 15776 15776 F: Documentation/networking/netconsole.rst 15777 15777 F: drivers/net/netconsole.c 15778 + F: tools/testing/selftests/drivers/net/netcons_basic.sh 15778 15779 15779 15780 NETDEVSIM 15780 15781 M: Jakub Kicinski <kuba@kernel.org>
+4 -1
tools/testing/selftests/drivers/net/Makefile
··· 1 1 # SPDX-License-Identifier: GPL-2.0 2 2 3 - TEST_INCLUDES := $(wildcard lib/py/*.py) 3 + TEST_INCLUDES := $(wildcard lib/py/*.py) \ 4 + ../../net/net_helper.sh \ 5 + ../../net/lib.sh \ 4 6 5 7 TEST_PROGS := \ 8 + netcons_basic.sh \ 6 9 ping.py \ 7 10 queues.py \ 8 11 stats.py \
+4
tools/testing/selftests/drivers/net/config
··· 1 1 CONFIG_IPV6=y 2 2 CONFIG_NETDEVSIM=m 3 + CONFIG_CONFIGFS_FS=y 4 + CONFIG_NETCONSOLE=m 5 + CONFIG_NETCONSOLE_DYNAMIC=y 6 + CONFIG_NETCONSOLE_EXTENDED_LOG=y
+234
tools/testing/selftests/drivers/net/netcons_basic.sh
··· 1 + #!/usr/bin/env bash 2 + # SPDX-License-Identifier: GPL-2.0 3 + 4 + # This test creates two netdevsim virtual interfaces, assigns one of them (the 5 + # "destination interface") to a new namespace, and assigns IP addresses to both 6 + # interfaces. 7 + # 8 + # It listens on the destination interface using socat and configures a dynamic 9 + # target on netconsole, pointing to the destination IP address. 10 + # 11 + # Finally, it checks whether the message was received properly on the 12 + # destination interface. Note that this test may pollute the kernel log buffer 13 + # (dmesg) and relies on dynamic configuration and namespaces being configured. 14 + # 15 + # Author: Breno Leitao <leitao@debian.org> 16 + 17 + set -euo pipefail 18 + 19 + SCRIPTDIR=$(dirname "$(readlink -e "${BASH_SOURCE[0]}")") 20 + 21 + # Simple script to test dynamic targets in netconsole 22 + SRCIF="" # to be populated later 23 + SRCIP=192.168.1.1 24 + DSTIF="" # to be populated later 25 + DSTIP=192.168.1.2 26 + 27 + PORT="6666" 28 + MSG="netconsole selftest" 29 + TARGET=$(mktemp -u netcons_XXXXX) 30 + DEFAULT_PRINTK_VALUES=$(cat /proc/sys/kernel/printk) 31 + NETCONS_CONFIGFS="/sys/kernel/config/netconsole" 32 + NETCONS_PATH="${NETCONS_CONFIGFS}"/"${TARGET}" 33 + # NAMESPACE will be populated by setup_ns with a random value 34 + NAMESPACE="" 35 + 36 + # IDs for netdevsim 37 + NSIM_DEV_1_ID=$((256 + RANDOM % 256)) 38 + NSIM_DEV_2_ID=$((512 + RANDOM % 256)) 39 + 40 + # Used to create and delete namespaces 41 + source "${SCRIPTDIR}"/../../net/lib.sh 42 + source "${SCRIPTDIR}"/../../net/net_helper.sh 43 + 44 + # Create netdevsim interfaces 45 + create_ifaces() { 46 + local NSIM_DEV_SYS_NEW=/sys/bus/netdevsim/new_device 47 + 48 + echo "$NSIM_DEV_2_ID" > "$NSIM_DEV_SYS_NEW" 49 + echo "$NSIM_DEV_1_ID" > "$NSIM_DEV_SYS_NEW" 50 + udevadm settle 2> /dev/null || true 51 + 52 + local NSIM1=/sys/bus/netdevsim/devices/netdevsim"$NSIM_DEV_1_ID" 53 + local NSIM2=/sys/bus/netdevsim/devices/netdevsim"$NSIM_DEV_2_ID" 54 + 55 + # These are global variables 56 + SRCIF=$(find "$NSIM1"/net -maxdepth 1 -type d ! \ 57 + -path "$NSIM1"/net -exec basename {} \;) 58 + DSTIF=$(find "$NSIM2"/net -maxdepth 1 -type d ! \ 59 + -path "$NSIM2"/net -exec basename {} \;) 60 + } 61 + 62 + link_ifaces() { 63 + local NSIM_DEV_SYS_LINK="/sys/bus/netdevsim/link_device" 64 + local SRCIF_IFIDX=$(cat /sys/class/net/"$SRCIF"/ifindex) 65 + local DSTIF_IFIDX=$(cat /sys/class/net/"$DSTIF"/ifindex) 66 + 67 + exec {NAMESPACE_FD}</var/run/netns/"${NAMESPACE}" 68 + exec {INITNS_FD}</proc/self/ns/net 69 + 70 + # Bind the dst interface to namespace 71 + ip link set "${DSTIF}" netns "${NAMESPACE}" 72 + 73 + # Linking one device to the other one (on the other namespace} 74 + if ! echo "${INITNS_FD}:$SRCIF_IFIDX $NAMESPACE_FD:$DSTIF_IFIDX" > $NSIM_DEV_SYS_LINK 75 + then 76 + echo "linking netdevsim1 with netdevsim2 should succeed" 77 + cleanup 78 + exit "${ksft_skip}" 79 + fi 80 + } 81 + 82 + function configure_ip() { 83 + # Configure the IPs for both interfaces 84 + ip netns exec "${NAMESPACE}" ip addr add "${DSTIP}"/24 dev "${DSTIF}" 85 + ip netns exec "${NAMESPACE}" ip link set "${DSTIF}" up 86 + 87 + ip addr add "${SRCIP}"/24 dev "${SRCIF}" 88 + ip link set "${SRCIF}" up 89 + } 90 + 91 + function set_network() { 92 + # setup_ns function is coming from lib.sh 93 + setup_ns NAMESPACE 94 + 95 + # Create both interfaces, and assign the destination to a different 96 + # namespace 97 + create_ifaces 98 + 99 + # Link both interfaces back to back 100 + link_ifaces 101 + 102 + configure_ip 103 + } 104 + 105 + function create_dynamic_target() { 106 + DSTMAC=$(ip netns exec "${NAMESPACE}" \ 107 + ip link show "${DSTIF}" | awk '/ether/ {print $2}') 108 + 109 + # Create a dynamic target 110 + mkdir "${NETCONS_PATH}" 111 + 112 + echo "${DSTIP}" > "${NETCONS_PATH}"/remote_ip 113 + echo "${SRCIP}" > "${NETCONS_PATH}"/local_ip 114 + echo "${DSTMAC}" > "${NETCONS_PATH}"/remote_mac 115 + echo "${SRCIF}" > "${NETCONS_PATH}"/dev_name 116 + 117 + echo 1 > "${NETCONS_PATH}"/enabled 118 + } 119 + 120 + function cleanup() { 121 + local NSIM_DEV_SYS_DEL="/sys/bus/netdevsim/del_device" 122 + 123 + # delete netconsole dynamic reconfiguration 124 + echo 0 > "${NETCONS_PATH}"/enabled 125 + # Remove the configfs entry 126 + rmdir "${NETCONS_PATH}" 127 + 128 + # Delete netdevsim devices 129 + echo "$NSIM_DEV_2_ID" > "$NSIM_DEV_SYS_DEL" 130 + echo "$NSIM_DEV_1_ID" > "$NSIM_DEV_SYS_DEL" 131 + 132 + # this is coming from lib.sh 133 + cleanup_all_ns 134 + 135 + # Restoring printk configurations 136 + echo "${DEFAULT_PRINTK_VALUES}" > /proc/sys/kernel/printk 137 + } 138 + 139 + function listen_port_and_save_to() { 140 + local OUTPUT=${1} 141 + # Just wait for 2 seconds 142 + timeout 2 ip netns exec "${NAMESPACE}" \ 143 + socat UDP-LISTEN:"${PORT}",fork "${OUTPUT}" 144 + } 145 + 146 + function validate_result() { 147 + local TMPFILENAME="$1" 148 + 149 + # Check if the file exists 150 + if [ ! -f "$TMPFILENAME" ]; then 151 + echo "FAIL: File was not generated." >&2 152 + exit "${ksft_fail}" 153 + fi 154 + 155 + if ! grep -q "${MSG}" "${TMPFILENAME}"; then 156 + echo "FAIL: ${MSG} not found in ${TMPFILENAME}" >&2 157 + cat "${TMPFILENAME}" >&2 158 + exit "${ksft_fail}" 159 + fi 160 + 161 + # Delete the file once it is validated, otherwise keep it 162 + # for debugging purposes 163 + rm "${TMPFILENAME}" 164 + exit "${ksft_pass}" 165 + } 166 + 167 + function check_for_dependencies() { 168 + if [ "$(id -u)" -ne 0 ]; then 169 + echo "This test must be run as root" >&2 170 + exit "${ksft_skip}" 171 + fi 172 + 173 + if ! which socat > /dev/null ; then 174 + echo "SKIP: socat(1) is not available" >&2 175 + exit "${ksft_skip}" 176 + fi 177 + 178 + if ! which ip > /dev/null ; then 179 + echo "SKIP: ip(1) is not available" >&2 180 + exit "${ksft_skip}" 181 + fi 182 + 183 + if ! which udevadm > /dev/null ; then 184 + echo "SKIP: udevadm(1) is not available" >&2 185 + exit "${ksft_skip}" 186 + fi 187 + 188 + if [ ! -d "${NETCONS_CONFIGFS}" ]; then 189 + echo "SKIP: directory ${NETCONS_CONFIGFS} does not exist. Check if NETCONSOLE_DYNAMIC is enabled" >&2 190 + exit "${ksft_skip}" 191 + fi 192 + 193 + if ip link show "${DSTIF}" 2> /dev/null; then 194 + echo "SKIP: interface ${DSTIF} exists in the system. Not overwriting it." >&2 195 + exit "${ksft_skip}" 196 + fi 197 + 198 + if ip addr list | grep -E "inet.*(${SRCIP}|${DSTIP})" 2> /dev/null; then 199 + echo "SKIP: IPs already in use. Skipping it" >&2 200 + exit "${ksft_skip}" 201 + fi 202 + } 203 + 204 + # ========== # 205 + # Start here # 206 + # ========== # 207 + modprobe netdevsim 2> /dev/null || true 208 + modprobe netconsole 2> /dev/null || true 209 + 210 + # The content of kmsg will be save to the following file 211 + OUTPUT_FILE="/tmp/${TARGET}" 212 + 213 + # Check for basic system dependency and exit if not found 214 + check_for_dependencies 215 + # Set current loglevel to KERN_INFO(6), and default to KERN_NOTICE(5) 216 + echo "6 5" > /proc/sys/kernel/printk 217 + # Remove the namespace, interfaces and netconsole target on exit 218 + trap cleanup EXIT 219 + # Create one namespace and two interfaces 220 + set_network 221 + # Create a dynamic target for netconsole 222 + create_dynamic_target 223 + # Listed for netconsole port inside the namespace and destination interface 224 + listen_port_and_save_to "${OUTPUT_FILE}" & 225 + # Wait for socat to start and listen to the port. 226 + wait_local_port_listen "${NAMESPACE}" "${PORT}" udp 227 + # Send the message 228 + echo "${MSG}: ${TARGET}" > /dev/kmsg 229 + # Wait until socat saves the file to disk 230 + busywait "${BUSYWAIT_TIMEOUT}" test -s "${OUTPUT_FILE}" 231 + 232 + # Make sure the message was received in the dst part 233 + # and exit 234 + validate_result "${OUTPUT_FILE}"