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Diffstat (limited to '')
-rw-r--r-- | tools/testing/selftests/livepatch/functions.sh | 344 |
1 files changed, 344 insertions, 0 deletions
diff --git a/tools/testing/selftests/livepatch/functions.sh b/tools/testing/selftests/livepatch/functions.sh new file mode 100644 index 000000000..c8416c54b --- /dev/null +++ b/tools/testing/selftests/livepatch/functions.sh @@ -0,0 +1,344 @@ +#!/bin/bash +# SPDX-License-Identifier: GPL-2.0 +# Copyright (C) 2018 Joe Lawrence <joe.lawrence@redhat.com> + +# Shell functions for the rest of the scripts. + +MAX_RETRIES=600 +RETRY_INTERVAL=".1" # seconds +KLP_SYSFS_DIR="/sys/kernel/livepatch" + +# Kselftest framework requirement - SKIP code is 4 +ksft_skip=4 + +# log(msg) - write message to kernel log +# msg - insightful words +function log() { + echo "$1" > /dev/kmsg +} + +# skip(msg) - testing can't proceed +# msg - explanation +function skip() { + log "SKIP: $1" + echo "SKIP: $1" >&2 + exit $ksft_skip +} + +# root test +function is_root() { + uid=$(id -u) + if [ $uid -ne 0 ]; then + echo "skip all tests: must be run as root" >&2 + exit $ksft_skip + fi +} + +# die(msg) - game over, man +# msg - dying words +function die() { + log "ERROR: $1" + echo "ERROR: $1" >&2 + exit 1 +} + +# save existing dmesg so we can detect new content +function save_dmesg() { + SAVED_DMESG=$(mktemp --tmpdir -t klp-dmesg-XXXXXX) + dmesg > "$SAVED_DMESG" +} + +# cleanup temporary dmesg file from save_dmesg() +function cleanup_dmesg_file() { + rm -f "$SAVED_DMESG" +} + +function push_config() { + DYNAMIC_DEBUG=$(grep '^kernel/livepatch' /sys/kernel/debug/dynamic_debug/control | \ + awk -F'[: ]' '{print "file " $1 " line " $2 " " $4}') + FTRACE_ENABLED=$(sysctl --values kernel.ftrace_enabled) +} + +function pop_config() { + if [[ -n "$DYNAMIC_DEBUG" ]]; then + echo -n "$DYNAMIC_DEBUG" > /sys/kernel/debug/dynamic_debug/control + fi + if [[ -n "$FTRACE_ENABLED" ]]; then + sysctl kernel.ftrace_enabled="$FTRACE_ENABLED" &> /dev/null + fi +} + +function set_dynamic_debug() { + cat <<-EOF > /sys/kernel/debug/dynamic_debug/control + file kernel/livepatch/* +p + func klp_try_switch_task -p + EOF +} + +function set_ftrace_enabled() { + local can_fail=0 + if [[ "$1" == "--fail" ]] ; then + can_fail=1 + shift + fi + + local err=$(sysctl -q kernel.ftrace_enabled="$1" 2>&1) + local result=$(sysctl --values kernel.ftrace_enabled) + + if [[ "$result" != "$1" ]] ; then + if [[ $can_fail -eq 1 ]] ; then + echo "livepatch: $err" | sed 's#/proc/sys/kernel/#kernel.#' > /dev/kmsg + return + fi + + skip "failed to set kernel.ftrace_enabled = $1" + fi + + echo "livepatch: kernel.ftrace_enabled = $result" > /dev/kmsg +} + +function cleanup() { + pop_config + cleanup_dmesg_file +} + +# setup_config - save the current config and set a script exit trap that +# restores the original config. Setup the dynamic debug +# for verbose livepatching output and turn on +# the ftrace_enabled sysctl. +function setup_config() { + is_root + push_config + set_dynamic_debug + set_ftrace_enabled 1 + trap cleanup EXIT INT TERM HUP +} + +# loop_until(cmd) - loop a command until it is successful or $MAX_RETRIES, +# sleep $RETRY_INTERVAL between attempts +# cmd - command and its arguments to run +function loop_until() { + local cmd="$*" + local i=0 + while true; do + eval "$cmd" && return 0 + [[ $((i++)) -eq $MAX_RETRIES ]] && return 1 + sleep $RETRY_INTERVAL + done +} + +function assert_mod() { + local mod="$1" + + modprobe --dry-run "$mod" &>/dev/null +} + +function is_livepatch_mod() { + local mod="$1" + + if [[ $(modinfo "$mod" | awk '/^livepatch:/{print $NF}') == "Y" ]]; then + return 0 + fi + + return 1 +} + +function __load_mod() { + local mod="$1"; shift + + local msg="% modprobe $mod $*" + log "${msg%% }" + ret=$(modprobe "$mod" "$@" 2>&1) + if [[ "$ret" != "" ]]; then + die "$ret" + fi + + # Wait for module in sysfs ... + loop_until '[[ -e "/sys/module/$mod" ]]' || + die "failed to load module $mod" +} + + +# load_mod(modname, params) - load a kernel module +# modname - module name to load +# params - module parameters to pass to modprobe +function load_mod() { + local mod="$1"; shift + + assert_mod "$mod" || + skip "unable to load module ${mod}, verify CONFIG_TEST_LIVEPATCH=m and run self-tests as root" + + is_livepatch_mod "$mod" && + die "use load_lp() to load the livepatch module $mod" + + __load_mod "$mod" "$@" +} + +# load_lp_nowait(modname, params) - load a kernel module with a livepatch +# but do not wait on until the transition finishes +# modname - module name to load +# params - module parameters to pass to modprobe +function load_lp_nowait() { + local mod="$1"; shift + + assert_mod "$mod" || + skip "unable to load module ${mod}, verify CONFIG_TEST_LIVEPATCH=m and run self-tests as root" + + is_livepatch_mod "$mod" || + die "module $mod is not a livepatch" + + __load_mod "$mod" "$@" + + # Wait for livepatch in sysfs ... + loop_until '[[ -e "/sys/kernel/livepatch/$mod" ]]' || + die "failed to load module $mod (sysfs)" +} + +# load_lp(modname, params) - load a kernel module with a livepatch +# modname - module name to load +# params - module parameters to pass to modprobe +function load_lp() { + local mod="$1"; shift + + load_lp_nowait "$mod" "$@" + + # Wait until the transition finishes ... + loop_until 'grep -q '^0$' /sys/kernel/livepatch/$mod/transition' || + die "failed to complete transition" +} + +# load_failing_mod(modname, params) - load a kernel module, expect to fail +# modname - module name to load +# params - module parameters to pass to modprobe +function load_failing_mod() { + local mod="$1"; shift + + local msg="% modprobe $mod $*" + log "${msg%% }" + ret=$(modprobe "$mod" "$@" 2>&1) + if [[ "$ret" == "" ]]; then + die "$mod unexpectedly loaded" + fi + log "$ret" +} + +# unload_mod(modname) - unload a kernel module +# modname - module name to unload +function unload_mod() { + local mod="$1" + + # Wait for module reference count to clear ... + loop_until '[[ $(cat "/sys/module/$mod/refcnt") == "0" ]]' || + die "failed to unload module $mod (refcnt)" + + log "% rmmod $mod" + ret=$(rmmod "$mod" 2>&1) + if [[ "$ret" != "" ]]; then + die "$ret" + fi + + # Wait for module in sysfs ... + loop_until '[[ ! -e "/sys/module/$mod" ]]' || + die "failed to unload module $mod (/sys/module)" +} + +# unload_lp(modname) - unload a kernel module with a livepatch +# modname - module name to unload +function unload_lp() { + unload_mod "$1" +} + +# disable_lp(modname) - disable a livepatch +# modname - module name to unload +function disable_lp() { + local mod="$1" + + log "% echo 0 > /sys/kernel/livepatch/$mod/enabled" + echo 0 > /sys/kernel/livepatch/"$mod"/enabled + + # Wait until the transition finishes and the livepatch gets + # removed from sysfs... + loop_until '[[ ! -e "/sys/kernel/livepatch/$mod" ]]' || + die "failed to disable livepatch $mod" +} + +# set_pre_patch_ret(modname, pre_patch_ret) +# modname - module name to set +# pre_patch_ret - new pre_patch_ret value +function set_pre_patch_ret { + local mod="$1"; shift + local ret="$1" + + log "% echo $ret > /sys/module/$mod/parameters/pre_patch_ret" + echo "$ret" > /sys/module/"$mod"/parameters/pre_patch_ret + + # Wait for sysfs value to hold ... + loop_until '[[ $(cat "/sys/module/$mod/parameters/pre_patch_ret") == "$ret" ]]' || + die "failed to set pre_patch_ret parameter for $mod module" +} + +function start_test { + local test="$1" + + save_dmesg + echo -n "TEST: $test ... " + log "===== TEST: $test =====" +} + +# check_result() - verify dmesg output +# TODO - better filter, out of order msgs, etc? +function check_result { + local expect="$*" + local result + + # Note: when comparing dmesg output, the kernel log timestamps + # help differentiate repeated testing runs. Remove them with a + # post-comparison sed filter. + + result=$(dmesg | comm --nocheck-order -13 "$SAVED_DMESG" - | \ + grep -e 'livepatch:' -e 'test_klp' | \ + grep -v '\(tainting\|taints\) kernel' | \ + sed 's/^\[[ 0-9.]*\] //') + + if [[ "$expect" == "$result" ]] ; then + echo "ok" + else + echo -e "not ok\n\n$(diff -upr --label expected --label result <(echo "$expect") <(echo "$result"))\n" + die "livepatch kselftest(s) failed" + fi + + cleanup_dmesg_file +} + +# check_sysfs_rights(modname, rel_path, expected_rights) - check sysfs +# path permissions +# modname - livepatch module creating the sysfs interface +# rel_path - relative path of the sysfs interface +# expected_rights - expected access rights +function check_sysfs_rights() { + local mod="$1"; shift + local rel_path="$1"; shift + local expected_rights="$1"; shift + + local path="$KLP_SYSFS_DIR/$mod/$rel_path" + local rights=$(/bin/stat --format '%A' "$path") + if test "$rights" != "$expected_rights" ; then + die "Unexpected access rights of $path: $expected_rights vs. $rights" + fi +} + +# check_sysfs_value(modname, rel_path, expected_value) - check sysfs value +# modname - livepatch module creating the sysfs interface +# rel_path - relative path of the sysfs interface +# expected_value - expected value read from the file +function check_sysfs_value() { + local mod="$1"; shift + local rel_path="$1"; shift + local expected_value="$1"; shift + + local path="$KLP_SYSFS_DIR/$mod/$rel_path" + local value=`cat $path` + if test "$value" != "$expected_value" ; then + die "Unexpected value in $path: $expected_value vs. $value" + fi +} |