Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
Merge tag 'livepatching-for-6.11' of git://git.kernel.org/pub/scm/linux/kernel/git/livepatching/livepatching
Pull livepatching update from Petr Mladek:
- show patch->replace flag in sysfs
- add or improve few selftests
* tag 'livepatching-for-6.11' of git://git.kernel.org/pub/scm/linux/kernel/git/livepatching/livepatching:
livepatch: Replace snprintf() with sysfs_emit()
selftests/livepatch: Add selftests for "replace" sysfs attribute
livepatch: Add "replace" sysfs attribute
selftests: livepatch: Test atomic replace against multiple modules
selftests/livepatch: define max test-syscall processes
+163
-53
+8
Documentation/ABI/testing/sysfs-kernel-livepatch
+8
Documentation/ABI/testing/sysfs-kernel-livepatch
···
47
47
disabled when the feature is used. See
48
48
Documentation/livepatch/livepatch.rst for more information.
49
49
50
+
What: /sys/kernel/livepatch/<patch>/replace
51
+
Date: Jun 2024
52
+
KernelVersion: 6.11.0
53
+
Contact: live-patching@vger.kernel.org
54
+
Description:
55
+
An attribute which indicates whether the patch supports
56
+
atomic-replace.
57
+
50
58
What: /sys/kernel/livepatch/<patch>/<object>
51
59
Date: Nov 2014
52
60
KernelVersion: 3.19.0
+14
-3
kernel/livepatch/core.c
+14
-3
kernel/livepatch/core.c
···
346
346
* /sys/kernel/livepatch/<patch>/enabled
347
347
* /sys/kernel/livepatch/<patch>/transition
348
348
* /sys/kernel/livepatch/<patch>/force
349
+
* /sys/kernel/livepatch/<patch>/replace
349
350
* /sys/kernel/livepatch/<patch>/<object>
350
351
* /sys/kernel/livepatch/<patch>/<object>/patched
351
352
* /sys/kernel/livepatch/<patch>/<object>/<function,sympos>
···
402
401
struct klp_patch *patch;
403
402
404
403
patch = container_of(kobj, struct klp_patch, kobj);
405
-
return snprintf(buf, PAGE_SIZE-1, "%d\n", patch->enabled);
404
+
return sysfs_emit(buf, "%d\n", patch->enabled);
406
405
}
407
406
408
407
static ssize_t transition_show(struct kobject *kobj,
···
411
410
struct klp_patch *patch;
412
411
413
412
patch = container_of(kobj, struct klp_patch, kobj);
414
-
return snprintf(buf, PAGE_SIZE-1, "%d\n",
415
-
patch == klp_transition_patch);
413
+
return sysfs_emit(buf, "%d\n", patch == klp_transition_patch);
416
414
}
417
415
418
416
static ssize_t force_store(struct kobject *kobj, struct kobj_attribute *attr,
···
443
443
return count;
444
444
}
445
445
446
+
static ssize_t replace_show(struct kobject *kobj,
447
+
struct kobj_attribute *attr, char *buf)
448
+
{
449
+
struct klp_patch *patch;
450
+
451
+
patch = container_of(kobj, struct klp_patch, kobj);
452
+
return sysfs_emit(buf, "%d\n", patch->replace);
453
+
}
454
+
446
455
static struct kobj_attribute enabled_kobj_attr = __ATTR_RW(enabled);
447
456
static struct kobj_attribute transition_kobj_attr = __ATTR_RO(transition);
448
457
static struct kobj_attribute force_kobj_attr = __ATTR_WO(force);
458
+
static struct kobj_attribute replace_kobj_attr = __ATTR_RO(replace);
449
459
static struct attribute *klp_patch_attrs[] = {
450
460
&enabled_kobj_attr.attr,
451
461
&transition_kobj_attr.attr,
452
462
&force_kobj_attr.attr,
463
+
&replace_kobj_attr.attr,
453
464
NULL
454
465
};
455
466
ATTRIBUTE_GROUPS(klp_patch);
+89
-49
tools/testing/selftests/livepatch/test-livepatch.sh
+89
-49
tools/testing/selftests/livepatch/test-livepatch.sh
···
4
4
5
5
. $(dirname $0)/functions.sh
6
6
7
-
MOD_LIVEPATCH=test_klp_livepatch
7
+
MOD_LIVEPATCH1=test_klp_livepatch
8
+
MOD_LIVEPATCH2=test_klp_syscall
9
+
MOD_LIVEPATCH3=test_klp_callbacks_demo
8
10
MOD_REPLACE=test_klp_atomic_replace
9
11
10
12
setup_config
···
18
16
19
17
start_test "basic function patching"
20
18
21
-
load_lp $MOD_LIVEPATCH
19
+
load_lp $MOD_LIVEPATCH1
22
20
23
-
if [[ "$(cat /proc/cmdline)" != "$MOD_LIVEPATCH: this has been live patched" ]] ; then
21
+
if [[ "$(cat /proc/cmdline)" != "$MOD_LIVEPATCH1: this has been live patched" ]] ; then
24
22
echo -e "FAIL\n\n"
25
23
die "livepatch kselftest(s) failed"
26
24
fi
27
25
28
-
disable_lp $MOD_LIVEPATCH
29
-
unload_lp $MOD_LIVEPATCH
26
+
disable_lp $MOD_LIVEPATCH1
27
+
unload_lp $MOD_LIVEPATCH1
30
28
31
-
if [[ "$(cat /proc/cmdline)" == "$MOD_LIVEPATCH: this has been live patched" ]] ; then
29
+
if [[ "$(cat /proc/cmdline)" == "$MOD_LIVEPATCH1: this has been live patched" ]] ; then
32
30
echo -e "FAIL\n\n"
33
31
die "livepatch kselftest(s) failed"
34
32
fi
35
33
36
-
check_result "% insmod test_modules/$MOD_LIVEPATCH.ko
37
-
livepatch: enabling patch '$MOD_LIVEPATCH'
38
-
livepatch: '$MOD_LIVEPATCH': initializing patching transition
39
-
livepatch: '$MOD_LIVEPATCH': starting patching transition
40
-
livepatch: '$MOD_LIVEPATCH': completing patching transition
41
-
livepatch: '$MOD_LIVEPATCH': patching complete
42
-
% echo 0 > /sys/kernel/livepatch/$MOD_LIVEPATCH/enabled
43
-
livepatch: '$MOD_LIVEPATCH': initializing unpatching transition
44
-
livepatch: '$MOD_LIVEPATCH': starting unpatching transition
45
-
livepatch: '$MOD_LIVEPATCH': completing unpatching transition
46
-
livepatch: '$MOD_LIVEPATCH': unpatching complete
47
-
% rmmod $MOD_LIVEPATCH"
34
+
check_result "% insmod test_modules/$MOD_LIVEPATCH1.ko
35
+
livepatch: enabling patch '$MOD_LIVEPATCH1'
36
+
livepatch: '$MOD_LIVEPATCH1': initializing patching transition
37
+
livepatch: '$MOD_LIVEPATCH1': starting patching transition
38
+
livepatch: '$MOD_LIVEPATCH1': completing patching transition
39
+
livepatch: '$MOD_LIVEPATCH1': patching complete
40
+
% echo 0 > /sys/kernel/livepatch/$MOD_LIVEPATCH1/enabled
41
+
livepatch: '$MOD_LIVEPATCH1': initializing unpatching transition
42
+
livepatch: '$MOD_LIVEPATCH1': starting unpatching transition
43
+
livepatch: '$MOD_LIVEPATCH1': completing unpatching transition
44
+
livepatch: '$MOD_LIVEPATCH1': unpatching complete
45
+
% rmmod $MOD_LIVEPATCH1"
48
46
49
47
50
48
# - load a livepatch that modifies the output from /proc/cmdline and
···
55
53
56
54
start_test "multiple livepatches"
57
55
58
-
load_lp $MOD_LIVEPATCH
56
+
load_lp $MOD_LIVEPATCH1
59
57
60
58
grep 'live patched' /proc/cmdline > /dev/kmsg
61
59
grep 'live patched' /proc/meminfo > /dev/kmsg
···
71
69
grep 'live patched' /proc/cmdline > /dev/kmsg
72
70
grep 'live patched' /proc/meminfo > /dev/kmsg
73
71
74
-
disable_lp $MOD_LIVEPATCH
75
-
unload_lp $MOD_LIVEPATCH
72
+
disable_lp $MOD_LIVEPATCH1
73
+
unload_lp $MOD_LIVEPATCH1
76
74
77
75
grep 'live patched' /proc/cmdline > /dev/kmsg
78
76
grep 'live patched' /proc/meminfo > /dev/kmsg
79
77
80
-
check_result "% insmod test_modules/$MOD_LIVEPATCH.ko
81
-
livepatch: enabling patch '$MOD_LIVEPATCH'
82
-
livepatch: '$MOD_LIVEPATCH': initializing patching transition
83
-
livepatch: '$MOD_LIVEPATCH': starting patching transition
84
-
livepatch: '$MOD_LIVEPATCH': completing patching transition
85
-
livepatch: '$MOD_LIVEPATCH': patching complete
86
-
$MOD_LIVEPATCH: this has been live patched
78
+
check_result "% insmod test_modules/$MOD_LIVEPATCH1.ko
79
+
livepatch: enabling patch '$MOD_LIVEPATCH1'
80
+
livepatch: '$MOD_LIVEPATCH1': initializing patching transition
81
+
livepatch: '$MOD_LIVEPATCH1': starting patching transition
82
+
livepatch: '$MOD_LIVEPATCH1': completing patching transition
83
+
livepatch: '$MOD_LIVEPATCH1': patching complete
84
+
$MOD_LIVEPATCH1: this has been live patched
87
85
% insmod test_modules/$MOD_REPLACE.ko replace=0
88
86
livepatch: enabling patch '$MOD_REPLACE'
89
87
livepatch: '$MOD_REPLACE': initializing patching transition
90
88
livepatch: '$MOD_REPLACE': starting patching transition
91
89
livepatch: '$MOD_REPLACE': completing patching transition
92
90
livepatch: '$MOD_REPLACE': patching complete
93
-
$MOD_LIVEPATCH: this has been live patched
91
+
$MOD_LIVEPATCH1: this has been live patched
94
92
$MOD_REPLACE: this has been live patched
95
93
% echo 0 > /sys/kernel/livepatch/$MOD_REPLACE/enabled
96
94
livepatch: '$MOD_REPLACE': initializing unpatching transition
···
98
96
livepatch: '$MOD_REPLACE': completing unpatching transition
99
97
livepatch: '$MOD_REPLACE': unpatching complete
100
98
% rmmod $MOD_REPLACE
101
-
$MOD_LIVEPATCH: this has been live patched
102
-
% echo 0 > /sys/kernel/livepatch/$MOD_LIVEPATCH/enabled
103
-
livepatch: '$MOD_LIVEPATCH': initializing unpatching transition
104
-
livepatch: '$MOD_LIVEPATCH': starting unpatching transition
105
-
livepatch: '$MOD_LIVEPATCH': completing unpatching transition
106
-
livepatch: '$MOD_LIVEPATCH': unpatching complete
107
-
% rmmod $MOD_LIVEPATCH"
99
+
$MOD_LIVEPATCH1: this has been live patched
100
+
% echo 0 > /sys/kernel/livepatch/$MOD_LIVEPATCH1/enabled
101
+
livepatch: '$MOD_LIVEPATCH1': initializing unpatching transition
102
+
livepatch: '$MOD_LIVEPATCH1': starting unpatching transition
103
+
livepatch: '$MOD_LIVEPATCH1': completing unpatching transition
104
+
livepatch: '$MOD_LIVEPATCH1': unpatching complete
105
+
% rmmod $MOD_LIVEPATCH1"
108
106
109
107
110
108
# - load a livepatch that modifies the output from /proc/cmdline and
111
109
# verify correct behavior
112
-
# - load an atomic replace livepatch and verify that only the second is active
113
-
# - remove the first livepatch and verify that the atomic replace livepatch
114
-
# is still active
110
+
# - load two additional livepatches and check the number of livepatch modules
111
+
# applied
112
+
# - load an atomic replace livepatch and check that the other three modules were
113
+
# disabled
114
+
# - remove all livepatches besides the atomic replace one and verify that the
115
+
# atomic replace livepatch is still active
115
116
# - remove the atomic replace livepatch and verify that none are active
116
117
117
118
start_test "atomic replace livepatch"
118
119
119
-
load_lp $MOD_LIVEPATCH
120
+
load_lp $MOD_LIVEPATCH1
120
121
121
122
grep 'live patched' /proc/cmdline > /dev/kmsg
122
123
grep 'live patched' /proc/meminfo > /dev/kmsg
124
+
125
+
for mod in $MOD_LIVEPATCH2 $MOD_LIVEPATCH3; do
126
+
load_lp "$mod"
127
+
done
128
+
129
+
mods=(/sys/kernel/livepatch/*)
130
+
nmods=${#mods[@]}
131
+
if [ "$nmods" -ne 3 ]; then
132
+
die "Expecting three modules listed, found $nmods"
133
+
fi
123
134
124
135
load_lp $MOD_REPLACE replace=1
125
136
126
137
grep 'live patched' /proc/cmdline > /dev/kmsg
127
138
grep 'live patched' /proc/meminfo > /dev/kmsg
128
139
129
-
unload_lp $MOD_LIVEPATCH
140
+
mods=(/sys/kernel/livepatch/*)
141
+
nmods=${#mods[@]}
142
+
if [ "$nmods" -ne 1 ]; then
143
+
die "Expecting only one moduled listed, found $nmods"
144
+
fi
145
+
146
+
# These modules were disabled by the atomic replace
147
+
for mod in $MOD_LIVEPATCH3 $MOD_LIVEPATCH2 $MOD_LIVEPATCH1; do
148
+
unload_lp "$mod"
149
+
done
130
150
131
151
grep 'live patched' /proc/cmdline > /dev/kmsg
132
152
grep 'live patched' /proc/meminfo > /dev/kmsg
···
159
135
grep 'live patched' /proc/cmdline > /dev/kmsg
160
136
grep 'live patched' /proc/meminfo > /dev/kmsg
161
137
162
-
check_result "% insmod test_modules/$MOD_LIVEPATCH.ko
163
-
livepatch: enabling patch '$MOD_LIVEPATCH'
164
-
livepatch: '$MOD_LIVEPATCH': initializing patching transition
165
-
livepatch: '$MOD_LIVEPATCH': starting patching transition
166
-
livepatch: '$MOD_LIVEPATCH': completing patching transition
167
-
livepatch: '$MOD_LIVEPATCH': patching complete
168
-
$MOD_LIVEPATCH: this has been live patched
138
+
check_result "% insmod test_modules/$MOD_LIVEPATCH1.ko
139
+
livepatch: enabling patch '$MOD_LIVEPATCH1'
140
+
livepatch: '$MOD_LIVEPATCH1': initializing patching transition
141
+
livepatch: '$MOD_LIVEPATCH1': starting patching transition
142
+
livepatch: '$MOD_LIVEPATCH1': completing patching transition
143
+
livepatch: '$MOD_LIVEPATCH1': patching complete
144
+
$MOD_LIVEPATCH1: this has been live patched
145
+
% insmod test_modules/$MOD_LIVEPATCH2.ko
146
+
livepatch: enabling patch '$MOD_LIVEPATCH2'
147
+
livepatch: '$MOD_LIVEPATCH2': initializing patching transition
148
+
livepatch: '$MOD_LIVEPATCH2': starting patching transition
149
+
livepatch: '$MOD_LIVEPATCH2': completing patching transition
150
+
livepatch: '$MOD_LIVEPATCH2': patching complete
151
+
% insmod test_modules/$MOD_LIVEPATCH3.ko
152
+
livepatch: enabling patch '$MOD_LIVEPATCH3'
153
+
livepatch: '$MOD_LIVEPATCH3': initializing patching transition
154
+
$MOD_LIVEPATCH3: pre_patch_callback: vmlinux
155
+
livepatch: '$MOD_LIVEPATCH3': starting patching transition
156
+
livepatch: '$MOD_LIVEPATCH3': completing patching transition
157
+
$MOD_LIVEPATCH3: post_patch_callback: vmlinux
158
+
livepatch: '$MOD_LIVEPATCH3': patching complete
169
159
% insmod test_modules/$MOD_REPLACE.ko replace=1
170
160
livepatch: enabling patch '$MOD_REPLACE'
171
161
livepatch: '$MOD_REPLACE': initializing patching transition
···
187
149
livepatch: '$MOD_REPLACE': completing patching transition
188
150
livepatch: '$MOD_REPLACE': patching complete
189
151
$MOD_REPLACE: this has been live patched
190
-
% rmmod $MOD_LIVEPATCH
152
+
% rmmod $MOD_LIVEPATCH3
153
+
% rmmod $MOD_LIVEPATCH2
154
+
% rmmod $MOD_LIVEPATCH1
191
155
$MOD_REPLACE: this has been live patched
192
156
% echo 0 > /sys/kernel/livepatch/$MOD_REPLACE/enabled
193
157
livepatch: '$MOD_REPLACE': initializing unpatching transition
+4
-1
tools/testing/selftests/livepatch/test-syscall.sh
+4
-1
tools/testing/selftests/livepatch/test-syscall.sh
···
15
15
16
16
start_test "patch getpid syscall while being heavily hammered"
17
17
18
-
for i in $(seq 1 $(getconf _NPROCESSORS_ONLN)); do
18
+
NPROC=$(getconf _NPROCESSORS_ONLN)
19
+
MAXPROC=128
20
+
21
+
for i in $(seq 1 $(($NPROC < $MAXPROC ? $NPROC : $MAXPROC))); do
19
22
./test_klp-call_getpid &
20
23
pids[$i]="$!"
21
24
done
+48
tools/testing/selftests/livepatch/test-sysfs.sh
+48
tools/testing/selftests/livepatch/test-sysfs.sh
···
18
18
check_sysfs_rights "$MOD_LIVEPATCH" "enabled" "-rw-r--r--"
19
19
check_sysfs_value "$MOD_LIVEPATCH" "enabled" "1"
20
20
check_sysfs_rights "$MOD_LIVEPATCH" "force" "--w-------"
21
+
check_sysfs_rights "$MOD_LIVEPATCH" "replace" "-r--r--r--"
21
22
check_sysfs_rights "$MOD_LIVEPATCH" "transition" "-r--r--r--"
22
23
check_sysfs_value "$MOD_LIVEPATCH" "transition" "0"
23
24
check_sysfs_rights "$MOD_LIVEPATCH" "vmlinux/patched" "-r--r--r--"
···
83
82
test_klp_callbacks_demo: post_unpatch_callback: vmlinux
84
83
livepatch: 'test_klp_callbacks_demo': unpatching complete
85
84
% rmmod test_klp_callbacks_demo"
85
+
86
+
start_test "sysfs test replace enabled"
87
+
88
+
MOD_LIVEPATCH=test_klp_atomic_replace
89
+
load_lp $MOD_LIVEPATCH replace=1
90
+
91
+
check_sysfs_rights "$MOD_LIVEPATCH" "replace" "-r--r--r--"
92
+
check_sysfs_value "$MOD_LIVEPATCH" "replace" "1"
93
+
94
+
disable_lp $MOD_LIVEPATCH
95
+
unload_lp $MOD_LIVEPATCH
96
+
97
+
check_result "% insmod test_modules/$MOD_LIVEPATCH.ko replace=1
98
+
livepatch: enabling patch '$MOD_LIVEPATCH'
99
+
livepatch: '$MOD_LIVEPATCH': initializing patching transition
100
+
livepatch: '$MOD_LIVEPATCH': starting patching transition
101
+
livepatch: '$MOD_LIVEPATCH': completing patching transition
102
+
livepatch: '$MOD_LIVEPATCH': patching complete
103
+
% echo 0 > /sys/kernel/livepatch/$MOD_LIVEPATCH/enabled
104
+
livepatch: '$MOD_LIVEPATCH': initializing unpatching transition
105
+
livepatch: '$MOD_LIVEPATCH': starting unpatching transition
106
+
livepatch: '$MOD_LIVEPATCH': completing unpatching transition
107
+
livepatch: '$MOD_LIVEPATCH': unpatching complete
108
+
% rmmod $MOD_LIVEPATCH"
109
+
110
+
start_test "sysfs test replace disabled"
111
+
112
+
load_lp $MOD_LIVEPATCH replace=0
113
+
114
+
check_sysfs_rights "$MOD_LIVEPATCH" "replace" "-r--r--r--"
115
+
check_sysfs_value "$MOD_LIVEPATCH" "replace" "0"
116
+
117
+
disable_lp $MOD_LIVEPATCH
118
+
unload_lp $MOD_LIVEPATCH
119
+
120
+
check_result "% insmod test_modules/$MOD_LIVEPATCH.ko replace=0
121
+
livepatch: enabling patch '$MOD_LIVEPATCH'
122
+
livepatch: '$MOD_LIVEPATCH': initializing patching transition
123
+
livepatch: '$MOD_LIVEPATCH': starting patching transition
124
+
livepatch: '$MOD_LIVEPATCH': completing patching transition
125
+
livepatch: '$MOD_LIVEPATCH': patching complete
126
+
% echo 0 > /sys/kernel/livepatch/$MOD_LIVEPATCH/enabled
127
+
livepatch: '$MOD_LIVEPATCH': initializing unpatching transition
128
+
livepatch: '$MOD_LIVEPATCH': starting unpatching transition
129
+
livepatch: '$MOD_LIVEPATCH': completing unpatching transition
130
+
livepatch: '$MOD_LIVEPATCH': unpatching complete
131
+
% rmmod $MOD_LIVEPATCH"
86
132
87
133
exit 0