1 files changed, 407 insertions, 0 deletions
diff --git a/tools/testing/selftests/livepatch/functions.sh b/tools/testing/selftests/livepatch/functions.sh
new file mode 100644
index 000000000000..8ec0cb64ad94
--- /dev/null
+++ b/tools/testing/selftests/livepatch/functions.sh
@@ -0,0 +1,407 @@
+#!/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
+SYSFS_KERNEL_DIR="/sys/kernel"
+SYSFS_KLP_DIR="$SYSFS_KERNEL_DIR/livepatch"
+SYSFS_DEBUG_DIR="$SYSFS_KERNEL_DIR/debug"
+SYSFS_KPROBES_DIR="$SYSFS_DEBUG_DIR/kprobes"
+if [[ -e /sys/kernel/tracing/trace ]]; then
+	SYSFS_TRACING_DIR="$SYSFS_KERNEL_DIR/tracing"
+else
+	SYSFS_TRACING_DIR="$SYSFS_DEBUG_DIR/tracing"
+fi
+
+# 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 $ksft_skip
+	fi
+}
+
+# Check if we can compile the modules before loading them
+function has_kdir() {
+	if [ -z "$KDIR" ]; then
+		KDIR="/lib/modules/$(uname -r)/build"
+	fi
+
+	if [ ! -d "$KDIR" ]; then
+		echo "skip all tests: KDIR ($KDIR) not available to compile modules."
+		exit $ksft_skip
+	fi
+}
+
+# die(msg) - game over, man
+#	msg - dying words
+function die() {
+	log "ERROR: $1"
+	echo "ERROR: $1" >&2
+	exit 1
+}
+
+function push_config() {
+	DYNAMIC_DEBUG=$(grep '^kernel/livepatch' "$SYSFS_DEBUG_DIR/dynamic_debug/control" | \
+			awk -F'[: ]' '{print "file " $1 " line " $2 " " $4}')
+	FTRACE_ENABLED=$(sysctl --values kernel.ftrace_enabled)
+	KPROBE_ENABLED=$(cat "$SYSFS_KPROBES_DIR/enabled")
+	TRACING_ON=$(cat "$SYSFS_TRACING_DIR/tracing_on")
+	CURRENT_TRACER=$(cat "$SYSFS_TRACING_DIR/current_tracer")
+	FTRACE_FILTER=$(cat "$SYSFS_TRACING_DIR/set_ftrace_filter")
+}
+
+function pop_config() {
+	if [[ -n "$DYNAMIC_DEBUG" ]]; then
+		echo -n "$DYNAMIC_DEBUG" > "$SYSFS_DEBUG_DIR/dynamic_debug/control"
+	fi
+	if [[ -n "$FTRACE_ENABLED" ]]; then
+		sysctl kernel.ftrace_enabled="$FTRACE_ENABLED" &> /dev/null
+	fi
+	if [[ -n "$KPROBE_ENABLED" ]]; then
+		echo "$KPROBE_ENABLED" > "$SYSFS_KPROBES_DIR/enabled"
+	fi
+	if [[ -n "$TRACING_ON" ]]; then
+		echo "$TRACING_ON" > "$SYSFS_TRACING_DIR/tracing_on"
+	fi
+	if [[ -n "$CURRENT_TRACER" ]]; then
+		echo "$CURRENT_TRACER" > "$SYSFS_TRACING_DIR/current_tracer"
+	fi
+	if [[ -n "$FTRACE_FILTER" ]]; then
+		echo "$FTRACE_FILTER" \
+			| sed -e "/#### all functions enabled ####/d" \
+			> "$SYSFS_TRACING_DIR/set_ftrace_filter"
+	fi
+}
+
+function set_dynamic_debug() {
+        cat <<-EOF > "$SYSFS_DEBUG_DIR/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
+}
+
+# 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
+	has_kdir
+	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 is_livepatch_mod() {
+	local mod="$1"
+
+	if [[ ! -f "test_modules/$mod.ko" ]]; then
+		die "Can't find \"test_modules/$mod.ko\", try \"make\""
+	fi
+
+	if [[ $(modinfo "test_modules/$mod.ko" | awk '/^livepatch:/{print $NF}') == "Y" ]]; then
+		return 0
+	fi
+
+	return 1
+}
+
+function __load_mod() {
+	local mod="$1"; shift
+
+	local msg="% insmod test_modules/$mod.ko $*"
+	log "${msg%% }"
+	ret=$(insmod "test_modules/$mod.ko" "$@" 2>&1)
+	if [[ "$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 insmod
+function load_mod() {
+	local mod="$1"; shift
+
+	is_livepatch_mod "$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 insmod
+function load_lp_nowait() {
+	local mod="$1"; shift
+
+	is_livepatch_mod "$mod" ||
+		die "module $mod is not a livepatch"
+
+	__load_mod "$mod" "$@"
+
+	# Wait for livepatch in sysfs ...
+	loop_until '[[ -e "$SYSFS_KLP_DIR/$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 insmod
+function load_lp() {
+	local mod="$1"; shift
+
+	load_lp_nowait "$mod" "$@"
+
+	# Wait until the transition finishes ...
+	loop_until 'grep -q '^0$' $SYSFS_KLP_DIR/$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 insmod
+function load_failing_mod() {
+	local mod="$1"; shift
+
+	local msg="% insmod test_modules/$mod.ko $*"
+	log "${msg%% }"
+	ret=$(insmod "test_modules/$mod.ko" "$@" 2>&1)
+	if [[ "$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 > $SYSFS_KLP_DIR/$mod/enabled"
+	echo 0 > "$SYSFS_KLP_DIR/$mod/enabled"
+
+	# Wait until the transition finishes and the livepatch gets
+	# removed from sysfs...
+	loop_until '[[ ! -e "$SYSFS_KLP_DIR/$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"
+
+	# Dump something unique into the dmesg log, then stash the entry
+	# in LAST_DMESG.  The check_result() function will use it to
+	# find new kernel messages since the test started.
+	local last_dmesg_msg="livepatch kselftest timestamp: $(date --rfc-3339=ns)"
+	log "$last_dmesg_msg"
+	loop_until 'dmesg | grep -q "$last_dmesg_msg"' ||
+		die "buffer busy? can't find canary dmesg message: $last_dmesg_msg"
+	LAST_DMESG=$(dmesg | grep "$last_dmesg_msg")
+
+	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
+
+	# Test results include any new dmesg entry since LAST_DMESG, then:
+	# - include lines matching keywords
+	# - exclude lines matching keywords
+	# - filter out dmesg timestamp prefixes
+	result=$(dmesg | awk -v last_dmesg="$LAST_DMESG" 'p; $0 == last_dmesg { p=1 }' | \
+		 grep -e 'livepatch:' -e 'test_klp' | \
+		 grep -v '\(tainting\|taints\) kernel' | \
+		 sed 's/^\[[ 0-9.]*\] //' | \
+		 sed 's/^\[[ ]*[CT][0-9]*\] //')
+
+	if [[ "$expect" == "$result" ]] ; then
+		echo "ok"
+	elif [[ "$result" == "" ]] ; then
+		echo -e "not ok\n\nbuffer overrun? can't find canary dmesg entry: $LAST_DMESG\n"
+		die "livepatch kselftest(s) failed"
+	else
+		echo -e "not ok\n\n$(diff -upr --label expected --label result <(echo "$expect") <(echo "$result"))\n"
+		die "livepatch kselftest(s) failed"
+	fi
+}
+
+# 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="$1"; shift
+
+	local path="$SYSFS_KLP_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="$1"; shift
+
+	local path="$SYSFS_KLP_DIR/$mod/$rel_path"
+	local value=`cat $path`
+	if test "$value" != "$expected_value" ; then
+		die "Unexpected value in $path: $expected_value vs. $value"
+	fi
+}
+
+# cleanup_tracing() - stop and clean up function tracing
+function cleanup_tracing() {
+	echo 0 > "$SYSFS_TRACING_DIR/tracing_on"
+	echo "" > "$SYSFS_TRACING_DIR/set_ftrace_filter"
+	echo "nop" > "$SYSFS_TRACING_DIR/current_tracer"
+	echo "" > "$SYSFS_TRACING_DIR/trace"
+}
+
+# trace_function(function) - start tracing of a function
+#	function - to be traced function
+function trace_function() {
+	local function="$1"; shift
+
+	cleanup_tracing
+
+	echo "function" > "$SYSFS_TRACING_DIR/current_tracer"
+	echo "$function" > "$SYSFS_TRACING_DIR/set_ftrace_filter"
+	echo 1 > "$SYSFS_TRACING_DIR/tracing_on"
+}
+
+# check_traced_functions(functions...) - check whether each function appeared in the trace log
+#	functions - list of functions to be checked
+function check_traced_functions() {
+	local function
+
+	for function in "$@"; do
+		if ! grep -Fwq "$function" "$SYSFS_TRACING_DIR/trace" ; then
+			die "Function ($function) did not appear in the trace"
+		fi
+	done
+
+	cleanup_tracing
+}