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[65.87.55.115]) by smtp.gmail.com with ESMTPSA id 8926c6da1cb9f-4d37ebf4ba4sm1640978173.35.2024.09.16.12.18.58 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 16 Sep 2024 12:18:58 -0700 (PDT) From: mitchell.augustin@canonical.com To: davem@davemloft.net, edumazet@google.com, kuba@kernel.org, pabeni@redhat.com, shuah@kernel.org, netdev@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org Cc: jacob.martin@canonical.com, dann.frazier@canonical.com, mitchell@mitchellaugustin.com Subject: [PATCH net-next] selftests: net: add pmtu_bad.sh regression test Date: Mon, 16 Sep 2024 14:18:57 -0500 Message-Id: <20240916191857.1082092-1-mitchell.augustin@canonical.com> X-Mailer: git-send-email 2.34.1 Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Patchwork-Delegate: kuba@kernel.org From: Mitchell Augustin Introduce a regression test that reproduces a bug in pmtu_ipv6_ipv6_exception which causes veth_A-R1's reference counter to remain > 0 after cleanup should have already completed. On affected kernels/platforms, running this test will result in the following being displayed repeatedly in dmesg: unregister_netdevice: waiting for veth_A-R1 to become free. Usage count = 5 and future attempts to modprobe/rmmod ip6_vti will hang forever. Link: https://lore.kernel.org/all/CAHTA-uZDaJ-71o+bo8a96TV4ck-8niimztQFaa=QoeNdUm-9wg@mail.gmail.com/ Requested-by: Jakub Kicinski Signed-off-by: Mitchell Augustin --- tools/testing/selftests/net/pmtu_bad.sh | 901 ++++++++++++++++++++++++ 1 file changed, 901 insertions(+) create mode 100755 tools/testing/selftests/net/pmtu_bad.sh diff --git a/tools/testing/selftests/net/pmtu_bad.sh b/tools/testing/selftests/net/pmtu_bad.sh new file mode 100755 index 000000000000..4bbc9815b661 --- /dev/null +++ b/tools/testing/selftests/net/pmtu_bad.sh @@ -0,0 +1,901 @@ +#!/bin/bash +# SPDX-License-Identifier: GPL-2.0 +# +# Pinned version of pmtu.sh pmtu_ipv6_ipv6_exception and all dependencies +# configured to reproduce a kernel bug where the veth_A-R1 device's +# resource counter remains > 0 after cleanup should have already been +# completed. +# +# On affected kernels/platforms, running this test will result in the following +# being displayed repeatedly in dmesg: +# unregister_netdevice: waiting for veth_A-R1 to become free. Usage count = 5 +# +# and future attempts to modprobe/rmmod ip6_vti will hang forever. +# +# Link: https://lore.kernel.org/all/CAHTA-uZDaJ-71o+bo8a96TV4ck-8niimztQFaa=QoeNdUm-9wg@mail.gmail.com/ +# +# BugLink: https://bugs.launchpad.net/ubuntu-kernel-tests/+bug/2072501 +# +# pmtu.sh: +# Check that route PMTU values match expectations, and that initial device MTU +# values are assigned correctly +# +# Tests currently implemented: +# +# - pmtu_bad +# Sets the CPU governor to "performance" for all CPUs, then +# runs a pinned, affected version of the pmtu_ipv6_ipv6_exception test with +# nexthop objects 100 times. If this causes the following to be output +# to dmesg, the test is considered to have failed and returns an error: +# +# unregister_netdevice: waiting for veth_A-R1 to become free +# +# Otherwise, the test passes. After execution of the test, the CPU governor +# is restored to its original settings. +# - pmtu_ipv6_ipv6_exception +# Same as pmtu_ipv4_vxlan4, but using a IPv4/IPv6 tunnel over IPv4/IPv6, +# instead of VXLAN + +# Pinned version of lib.sh +############################################################################## +# Defines + +WAIT_TIMEOUT=${WAIT_TIMEOUT:=20} +BUSYWAIT_TIMEOUT=$((WAIT_TIMEOUT * 1000)) # ms + +# Kselftest framework requirement - SKIP code is 4. +ksft_skip=4 +# namespace list created by setup_ns +NS_LIST=() + +############################################################################## +# Helpers + +__ksft_status_merge() +{ + local a=$1; shift + local b=$1; shift + local -A weights + local weight=0 + + local i + for i in "$@"; do + weights[$i]=$((weight++)) + done + + if [[ ${weights[$a]} > ${weights[$b]} ]]; then + echo "$a" + return 0 + else + echo "$b" + return 1 + fi +} + +ksft_status_merge() +{ + local a=$1; shift + local b=$1; shift + + __ksft_status_merge "$a" "$b" \ + $ksft_pass $ksft_xfail $ksft_skip $ksft_fail +} + +ksft_exit_status_merge() +{ + local a=$1; shift + local b=$1; shift + + __ksft_status_merge "$a" "$b" \ + $ksft_xfail $ksft_pass $ksft_skip $ksft_fail +} + +loopy_wait() +{ + local sleep_cmd=$1; shift + local timeout_ms=$1; shift + + local start_time="$(date -u +%s%3N)" + while true + do + local out + if out=$("$@"); then + echo -n "$out" + return 0 + fi + + local current_time="$(date -u +%s%3N)" + if ((current_time - start_time > timeout_ms)); then + echo -n "$out" + return 1 + fi + + $sleep_cmd + done +} + +busywait() +{ + local timeout_ms=$1; shift + + loopy_wait : "$timeout_ms" "$@" +} + +# timeout in seconds +slowwait() +{ + local timeout_sec=$1; shift + + loopy_wait "sleep 0.1" "$((timeout_sec * 1000))" "$@" +} + +until_counter_is() +{ + local expr=$1; shift + local current=$("$@") + + echo $((current)) + ((current $expr)) +} + +busywait_for_counter() +{ + local timeout=$1; shift + local delta=$1; shift + + local base=$("$@") + busywait "$timeout" until_counter_is ">= $((base + delta))" "$@" +} + +slowwait_for_counter() +{ + local timeout=$1; shift + local delta=$1; shift + + local base=$("$@") + slowwait "$timeout" until_counter_is ">= $((base + delta))" "$@" +} + +cleanup_ns() +{ + local ns="" + local errexit=0 + local ret=0 + + # disable errexit temporary + if [[ $- =~ "e" ]]; then + errexit=1 + set +e + fi + + for ns in "$@"; do + [ -z "${ns}" ] && continue + ip netns delete "${ns}" &> /dev/null + if ! busywait $BUSYWAIT_TIMEOUT ip netns list \| grep -vq "^$ns$" &> /dev/null; then + echo "Warn: Failed to remove namespace $ns" + ret=1 + fi + done + + [ $errexit -eq 1 ] && set -e + return $ret +} + +cleanup_all_ns() +{ + cleanup_ns "${NS_LIST[@]}" +} + +# setup netns with given names as prefix. e.g +# setup_ns local remote +setup_ns() +{ + local ns="" + local ns_name="" + local ns_list=() + local ns_exist= + for ns_name in "$@"; do + # Some test may setup/remove same netns multi times + if unset ${ns_name} 2> /dev/null; then + ns="${ns_name,,}-$(mktemp -u XXXXXX)" + eval readonly ${ns_name}="$ns" + ns_exist=false + else + eval ns='$'${ns_name} + cleanup_ns "$ns" + ns_exist=true + fi + + if ! ip netns add "$ns"; then + echo "Failed to create namespace $ns_name" + cleanup_ns "${ns_list[@]}" + return $ksft_skip + fi + ip -n "$ns" link set lo up + ! $ns_exist && ns_list+=("$ns") + done + NS_LIST+=("${ns_list[@]}") +} + +tc_rule_stats_get() +{ + local dev=$1; shift + local pref=$1; shift + local dir=$1; shift + local selector=${1:-.packets}; shift + + tc -j -s filter show dev $dev ${dir:-ingress} pref $pref \ + | jq ".[1].options.actions[].stats$selector" +} + +tc_rule_handle_stats_get() +{ + local id=$1; shift + local handle=$1; shift + local selector=${1:-.packets}; shift + local netns=${1:-""}; shift + + tc $netns -j -s filter show $id \ + | jq ".[] | select(.options.handle == $handle) | \ + .options.actions[0].stats$selector" +} + +# Pinned version of net_helper.sh +wait_local_port_listen() +{ + local listener_ns="${1}" + local port="${2}" + local protocol="${3}" + local pattern + local i + + pattern=":$(printf "%04X" "${port}") " + + # for tcp protocol additionally check the socket state + [ ${protocol} = "tcp" ] && pattern="${pattern}0A" + for i in $(seq 10); do + if ip netns exec "${listener_ns}" awk '{print $2" "$4}' \ + /proc/net/"${protocol}"* | grep -q "${pattern}"; then + break + fi + sleep 0.1 + done +} + + + +PAUSE_ON_FAIL=no +VERBOSE=0 +TRACING=0 + +# Some systems don't have a ping6 binary anymore +which ping6 > /dev/null 2>&1 && ping6=$(which ping6) || ping6=$(which ping) + +# Name Description re-run with nh +tests=" + pmtu_bad Runs IPv6 over IPv6: PMTU exceptions 100x w/ performance governor 1" + +# Addressing and routing for tests with routers: four network segments, with +# index SEGMENT between 1 and 4, a common prefix (PREFIX4 or PREFIX6) and an +# identifier ID, which is 1 for hosts (A and B), 2 for routers (R1 and R2). +# Addresses are: +# - IPv4: PREFIX4.SEGMENT.ID (/24) +# - IPv6: PREFIX6:SEGMENT::ID (/64) +prefix4="10.0" +prefix6="fc00" +a_r1=1 +a_r2=2 +b_r1=3 +b_r2=4 +# ns peer segment +routing_addrs=" + A R1 ${a_r1} + A R2 ${a_r2} + B R1 ${b_r1} + B R2 ${b_r2} +" +# Traffic from A to B goes through R1 by default, and through R2, if destined to +# B's address on the b_r2 segment. +# Traffic from B to A goes through R1. +# ns destination gateway +routes=" + A default ${prefix4}.${a_r1}.2 + A ${prefix4}.${b_r2}.1 ${prefix4}.${a_r2}.2 + B default ${prefix4}.${b_r1}.2 + + A default ${prefix6}:${a_r1}::2 + A ${prefix6}:${b_r2}::1 ${prefix6}:${a_r2}::2 + B default ${prefix6}:${b_r1}::2 +" +USE_NH="no" +# ns family nh id destination gateway +nexthops=" + A 4 41 ${prefix4}.${a_r1}.2 veth_A-R1 + A 4 42 ${prefix4}.${a_r2}.2 veth_A-R2 + B 4 41 ${prefix4}.${b_r1}.2 veth_B-R1 + + A 6 61 ${prefix6}:${a_r1}::2 veth_A-R1 + A 6 62 ${prefix6}:${a_r2}::2 veth_A-R2 + B 6 61 ${prefix6}:${b_r1}::2 veth_B-R1 +" + +# nexthop id correlates to id in nexthops config above +# ns family prefix nh id +routes_nh=" + A 4 default 41 + A 4 ${prefix4}.${b_r2}.1 42 + B 4 default 41 + + A 6 default 61 + A 6 ${prefix6}:${b_r2}::1 62 + B 6 default 61 +" + +policy_mark=0x04 +rt_table=main + +veth4_a_addr="192.168.1.1" +veth4_b_addr="192.168.1.2" +veth4_c_addr="192.168.2.10" +veth4_mask="24" +veth6_a_addr="fd00:1::a" +veth6_b_addr="fd00:1::b" +veth6_c_addr="fd00:2::c" +veth6_mask="64" + +tunnel4_a_addr="192.168.2.1" +tunnel4_b_addr="192.168.2.2" +tunnel4_mask="24" +tunnel6_a_addr="fd00:2::a" +tunnel6_b_addr="fd00:2::b" +tunnel6_mask="64" + +dummy6_0_prefix="fc00:1000::" +dummy6_1_prefix="fc00:1001::" +dummy6_mask="64" + +err_buf= +tcpdump_pids= +nettest_pids= +socat_pids= +tmpoutfile= + +err() { + err_buf="${err_buf}${1} +" +} + +err_flush() { + echo -n "${err_buf}" + err_buf= +} + +run_cmd() { + cmd="$*" + + if [ "$VERBOSE" = "1" ]; then + printf " COMMAND: $cmd\n" + fi + + out="$($cmd 2>&1)" + rc=$? + if [ "$VERBOSE" = "1" -a -n "$out" ]; then + echo " $out" + echo + fi + + return $rc +} + +run_cmd_bg() { + cmd="$*" + + if [ "$VERBOSE" = "1" ]; then + printf " COMMAND: %s &\n" "${cmd}" + fi + + $cmd 2>&1 & +} + +# Find the auto-generated name for this namespace +nsname() { + eval echo \$NS_$1 +} + +setup_ipvX_over_ipvY() { + inner=${1} + outer=${2} + + if [ "${outer}" -eq 4 ]; then + a_addr="${prefix4}.${a_r1}.1" + b_addr="${prefix4}.${b_r1}.1" + if [ "${inner}" -eq 4 ]; then + type="ipip" + mode="ipip" + else + type="sit" + mode="ip6ip" + fi + else + a_addr="${prefix6}:${a_r1}::1" + b_addr="${prefix6}:${b_r1}::1" + type="ip6tnl" + if [ "${inner}" -eq 4 ]; then + mode="ipip6" + else + mode="ip6ip6" + fi + fi + + run_cmd ${ns_a} ip link add ip_a type ${type} local ${a_addr} remote ${b_addr} mode ${mode} || return $ksft_skip + run_cmd ${ns_b} ip link add ip_b type ${type} local ${b_addr} remote ${a_addr} mode ${mode} + + run_cmd ${ns_a} ip link set ip_a up + run_cmd ${ns_b} ip link set ip_b up + + if [ "${inner}" = "4" ]; then + run_cmd ${ns_a} ip addr add ${tunnel4_a_addr}/${tunnel4_mask} dev ip_a + run_cmd ${ns_b} ip addr add ${tunnel4_b_addr}/${tunnel4_mask} dev ip_b + else + run_cmd ${ns_a} ip addr add ${tunnel6_a_addr}/${tunnel6_mask} dev ip_a + run_cmd ${ns_b} ip addr add ${tunnel6_b_addr}/${tunnel6_mask} dev ip_b + fi +} + +setup_ip6ip6() { + setup_ipvX_over_ipvY 6 6 +} + +setup_namespaces() { + setup_ns NS_A NS_B NS_C NS_R1 NS_R2 + for n in ${NS_A} ${NS_B} ${NS_C} ${NS_R1} ${NS_R2}; do + # Disable DAD, so that we don't have to wait to use the + # configured IPv6 addresses + ip netns exec ${n} sysctl -q net/ipv6/conf/default/accept_dad=0 + done + ns_a="ip netns exec ${NS_A}" + ns_b="ip netns exec ${NS_B}" + ns_c="ip netns exec ${NS_C}" + ns_r1="ip netns exec ${NS_R1}" + ns_r2="ip netns exec ${NS_R2}" +} + + +setup_routing_old() { + for i in ${routes}; do + [ "${ns}" = "" ] && ns="${i}" && continue + [ "${addr}" = "" ] && addr="${i}" && continue + [ "${gw}" = "" ] && gw="${i}" + + ns_name="$(nsname ${ns})" + + ip -n "${ns_name}" route add "${addr}" table "${rt_table}" via "${gw}" + + ns=""; addr=""; gw="" + done +} + +setup_routing_new() { + for i in ${nexthops}; do + [ "${ns}" = "" ] && ns="${i}" && continue + [ "${fam}" = "" ] && fam="${i}" && continue + [ "${nhid}" = "" ] && nhid="${i}" && continue + [ "${gw}" = "" ] && gw="${i}" && continue + [ "${dev}" = "" ] && dev="${i}" + + ns_name="$(nsname ${ns})" + + ip -n ${ns_name} -${fam} nexthop add id ${nhid} via ${gw} dev ${dev} + + ns=""; fam=""; nhid=""; gw=""; dev="" + + done + + for i in ${routes_nh}; do + [ "${ns}" = "" ] && ns="${i}" && continue + [ "${fam}" = "" ] && fam="${i}" && continue + [ "${addr}" = "" ] && addr="${i}" && continue + [ "${nhid}" = "" ] && nhid="${i}" + + ns_name="$(nsname ${ns})" + + ip -n "${ns_name}" -"${fam}" route add "${addr}" table "${rt_table}" nhid "${nhid}" + + ns=""; fam=""; addr=""; nhid="" + done +} + +setup_routing() { + for i in ${NS_R1} ${NS_R2}; do + ip netns exec ${i} sysctl -q net/ipv4/ip_forward=1 + ip netns exec ${i} sysctl -q net/ipv6/conf/all/forwarding=1 + done + + for i in ${routing_addrs}; do + [ "${ns}" = "" ] && ns="${i}" && continue + [ "${peer}" = "" ] && peer="${i}" && continue + [ "${segment}" = "" ] && segment="${i}" + + ns_name="$(nsname ${ns})" + peer_name="$(nsname ${peer})" + if="veth_${ns}-${peer}" + ifpeer="veth_${peer}-${ns}" + + # Create veth links + ip link add ${if} up netns ${ns_name} type veth peer name ${ifpeer} netns ${peer_name} || return 1 + ip -n ${peer_name} link set dev ${ifpeer} up + + # Add addresses + ip -n ${ns_name} addr add ${prefix4}.${segment}.1/24 dev ${if} + ip -n ${ns_name} addr add ${prefix6}:${segment}::1/64 dev ${if} + + ip -n ${peer_name} addr add ${prefix4}.${segment}.2/24 dev ${ifpeer} + ip -n ${peer_name} addr add ${prefix6}:${segment}::2/64 dev ${ifpeer} + + ns=""; peer=""; segment="" + done + + if [ "$USE_NH" = "yes" ]; then + setup_routing_new + else + setup_routing_old + fi + + return 0 +} + + +setup() { + [ "$(id -u)" -ne 0 ] && echo " need to run as root" && return $ksft_skip + + for arg do + eval setup_${arg} || { echo " ${arg} not supported"; return 1; } + done +} + +trace() { + [ $TRACING -eq 0 ] && return + + for arg do + [ "${ns_cmd}" = "" ] && ns_cmd="${arg}" && continue + ${ns_cmd} tcpdump --immediate-mode -s 0 -i "${arg}" -w "${name}_${arg}.pcap" 2> /dev/null & + tcpdump_pids="${tcpdump_pids} $!" + ns_cmd= + done + sleep 1 +} + + +restore_governors() { + echo "Restoring original CPU governors" + while IFS=' ' read -r cpu governor; do + echo "$governor" | tee "/sys/devices/system/cpu/$cpu/cpufreq/scaling_governor" > /dev/null + done < "$GOVERNOR_STATE_FILE" + rm -rf "$STATE_FILE_DIR" 2>/dev/null +} + + +cleanup() { + for pid in ${tcpdump_pids}; do + kill ${pid} + done + tcpdump_pids= + + for pid in ${nettest_pids}; do + kill ${pid} + done + nettest_pids= + + for pid in ${socat_pids}; do + kill "${pid}" + done + socat_pids= + + cleanup_all_ns + + ip link del veth_A-C 2>/dev/null + ip link del veth_A-R1 2>/dev/null + ovs-vsctl --if-exists del-port vxlan_a 2>/dev/null + ovs-vsctl --if-exists del-br ovs_br0 2>/dev/null + rm -f "$tmpoutfile" +} + +mtu() { + ns_cmd="${1}" + dev="${2}" + mtu="${3}" + + ${ns_cmd} ip link set dev ${dev} mtu ${mtu} +} + +mtu_parse() { + input="${1}" + + next=0 + for i in ${input}; do + [ ${next} -eq 1 -a "${i}" = "lock" ] && next=2 && continue + [ ${next} -eq 1 ] && echo "${i}" && return + [ ${next} -eq 2 ] && echo "lock ${i}" && return + [ "${i}" = "mtu" ] && next=1 + done +} + +link_get() { + ns_cmd="${1}" + name="${2}" + + ${ns_cmd} ip link show dev "${name}" +} + +link_get_mtu() { + ns_cmd="${1}" + name="${2}" + + mtu_parse "$(link_get "${ns_cmd}" ${name})" +} + +route_get_dst_exception() { + ns_cmd="${1}" + dst="${2}" + dsfield="${3}" + + if [ -z "${dsfield}" ]; then + dsfield=0 + fi + + ${ns_cmd} ip route get "${dst}" dsfield "${dsfield}" +} + +route_get_dst_pmtu_from_exception() { + ns_cmd="${1}" + dst="${2}" + dsfield="${3}" + + mtu_parse "$(route_get_dst_exception "${ns_cmd}" "${dst}" "${dsfield}")" +} + +check_pmtu_value() { + expected="${1}" + value="${2}" + event="${3}" + + [ "${expected}" = "any" ] && [ -n "${value}" ] && return 0 + [ "${value}" = "${expected}" ] && return 0 + [ -z "${value}" ] && err " PMTU exception wasn't created after ${event}" && return 1 + [ -z "${expected}" ] && err " PMTU exception shouldn't exist after ${event}" && return 1 + err " found PMTU exception with incorrect MTU ${value}, expected ${expected}, after ${event}" + return 1 +} + + +test_pmtu_ipvX_over_ipvY_exception() { + inner=${1} + outer=${2} + ll_mtu=4000 + + setup namespaces routing ip${inner}ip${outer} || return $ksft_skip + + trace "${ns_a}" ip_a "${ns_b}" ip_b \ + "${ns_a}" veth_A-R1 "${ns_r1}" veth_R1-A \ + "${ns_b}" veth_B-R1 "${ns_r1}" veth_R1-B + + if [ ${inner} -eq 4 ]; then + ping=ping + dst=${tunnel4_b_addr} + else + ping=${ping6} + dst=${tunnel6_b_addr} + fi + + if [ ${outer} -eq 4 ]; then + # IPv4 header + exp_mtu=$((${ll_mtu} - 20)) + else + # IPv6 header Option 4 + exp_mtu=$((${ll_mtu} - 40 - 8)) + fi + + # Create route exception by exceeding link layer MTU + mtu "${ns_a}" veth_A-R1 $((${ll_mtu} + 1000)) + mtu "${ns_r1}" veth_R1-A $((${ll_mtu} + 1000)) + mtu "${ns_b}" veth_B-R1 ${ll_mtu} + mtu "${ns_r1}" veth_R1-B ${ll_mtu} + + mtu "${ns_a}" ip_a $((${ll_mtu} + 1000)) || return + mtu "${ns_b}" ip_b $((${ll_mtu} + 1000)) || return + run_cmd ${ns_a} ${ping} -q -M want -i 0.1 -w 1 -s $((${ll_mtu} + 500)) ${dst} + + # Check that exception was created + pmtu="$(route_get_dst_pmtu_from_exception "${ns_a}" ${dst})" + check_pmtu_value ${exp_mtu} "${pmtu}" "exceeding link layer MTU on ip${inner}ip${outer} interface" +} + +test_pmtu_ipv6_ipv6_exception() { + test_pmtu_ipvX_over_ipvY_exception 6 6 +} + +run_test() { + ( + tname="$1" + tdesc="$2" + + unset IFS + + # Since cleanup() relies on variables modified by this subshell, it + # has to run in this context. + trap cleanup EXIT + + if [ "$VERBOSE" = "1" ]; then + printf "\n##########################################################################\n\n" + fi + + eval test_${tname} + ret=$? + + if [ $ret -eq 0 ]; then + printf "TEST: %-60s [ OK ]\n" "${tdesc}" + elif [ $ret -eq 1 ]; then + printf "TEST: %-60s [FAIL]\n" "${tdesc}" + if [ "${PAUSE_ON_FAIL}" = "yes" ]; then + echo + echo "Pausing. Hit enter to continue" + read a + fi + err_flush + exit 1 + elif [ $ret -eq $ksft_skip ]; then + printf "TEST: %-60s [SKIP]\n" "${tdesc}" + err_flush + fi + + return $ret + ) + ret=$? + case $ret in + 0) + all_skipped=false + [ $exitcode -eq $ksft_skip ] && exitcode=0 + ;; + $ksft_skip) + [ $all_skipped = true ] && exitcode=$ksft_skip + ;; + *) + all_skipped=false + exitcode=1 + ;; + esac + + return $ret +} + +run_test_nh() { + tname="$1" + tdesc="$2" + + USE_NH=yes + run_test "${tname}" "${tdesc} - nexthop objects" + USE_NH=no +} + +usage() { + echo + echo "$0 [OPTIONS]..." + echo "Runs pmtu_ipv6_ipv6_exception test 100x" + echo + echo "Options" + echo " --trace: capture traffic to TEST_INTERFACE.pcap" + echo + echo "Available tests${tests}" + exit 1 +} + +################################################################################ +# + +[ "$(id -u)" -ne 0 ] && echo "ERROR: need to run as root" && exit 1 +exitcode=0 +desc=0 +all_skipped=true + +while getopts :ptv o +do + case $o in + p) PAUSE_ON_FAIL=yes;; + v) VERBOSE=1;; + t) if which tcpdump > /dev/null 2>&1; then + TRACING=1 + else + echo "=== tcpdump not available, tracing disabled" + fi + ;; + *) usage;; + esac +done +shift $(($OPTIND-1)) + +IFS=" +" + +for arg do + # Check first that all requested tests are available before running any + command -v > /dev/null "test_${arg}" || { echo "=== Test ${arg} not found"; usage; } +done + +trap cleanup EXIT + +# start clean +cleanup + +HAVE_NH=no +ip nexthop ls >/dev/null 2>&1 +[ $? -eq 0 ] && HAVE_NH=yes + +name="" +desc="" +rerun_nh=0 + +# Set to performance governor so we can reproduce the bug +STATE_FILE_DIR=$(mktemp -d) +if [[ ! -d "$STATE_FILE_DIR" ]]; then + echo "Could not create temp dir, skipping this test" >&2 + exit 1 +fi + +# Save current CPU governor state to temp file +GOVERNOR_STATE_FILE="$STATE_FILE_DIR/orig_cpu_governors.txt" +touch $GOVERNOR_STATE_FILE +if [[ ! -e "$GOVERNOR_STATE_FILE" ]]; then + echo "Could not save current performance governor states, skipping this test" >&2 + exit 1 +fi +echo "Saving current performance governor settings" +for cpu in /sys/devices/system/cpu/cpu*/cpufreq/scaling_governor; do + if [[ $cpu =~ ^/sys/devices/system/cpu/(cpu[0-9]+)/cpufreq/scaling_governor$ ]]; then + echo "${BASH_REMATCH[1]} $(cat $cpu)" >> "$GOVERNOR_STATE_FILE" + fi +done + +# Restore original CPU governor settings +trap restore_governors EXIT + +echo "Switching CPU governor to performance" +for cpu in /sys/devices/system/cpu/cpu*/cpufreq/scaling_governor; do + if [[ $cpu =~ ^/sys/devices/system/cpu/(cpu[0-9]+)/cpufreq/scaling_governor$ ]]; then + echo "performance" | tee $cpu > /dev/null + fi +done + +for i in $(seq 1 100); +do + name="pmtu_ipv6_ipv6_exception" + desc="Bad PMTU behavior" + + if [ "${HAVE_NH}" = "yes" ]; then + rerun_nh="${t}" + fi + + run_this=1 + for arg do + [ "${arg}" != "${arg#--*}" ] && continue + [ "${arg}" = "${name}" ] && run_this=1 && break + run_this=0 + done + if [ $run_this -eq 1 ]; then + run_test_nh "${name}" "${desc}" + fi + name="" + desc="" + rerun_nh=0 +done + +if dmesg | grep -q "unregister_netdevice: waiting for veth_A-R1 to become free"; then + printf "TEST: Bad PMTU behavior - veth_A-R1 refcount error reproducer [FAIL]\n" + printf "veth_A-R1 has not been released properly\n" + exitcode=1 +else + printf "TEST: Bad PMTU behavior - veth_A-R1 refcount error reproducer [PASS]\n" + printf "No veth_A-R1 errors, considering this test passed\n" + exitcode=0 +fi + +exit ${exitcode}