1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
|
#!/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
# 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() {
result=$(sysctl kernel.ftrace_enabled="$1" 2>&1 | paste --serial --delimiters=' ')
echo "livepatch: $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: $test ... "
}
# check_result() - verify dmesg output
# TODO - better filter, out of order msgs, etc?
function check_result {
local expect="$*"
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=$(dmesg | diff --changed-group-format='%>' --unchanged-group-format='' "$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
}
|