Commit d3d9443f authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge tag 'livepatching-for-7.1' of... 

Merge tag 'livepatching-for-7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/livepatching/livepatching

Pull livepatching updates from Petr Mladek:

 - Add two new selftests

* tag 'livepatching-for-7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/livepatching/livepatching:
  selftests/livepatch: add test for module function patching
  selftests: livepatch: test-ftrace: livepatch a traced function
parents 090748e6 448c0f8c

tools/testing/selftests/livepatch/test-ftrace.sh

+36 −0
Original line number Diff line number Diff line
@@ -95,4 +95,40 @@ livepatch: '$MOD_LIVEPATCH': completing unpatching transition 
livepatch: '$MOD_LIVEPATCH': unpatching complete

% rmmod $MOD_LIVEPATCH"





# - trace a function

# - verify livepatch can load targgeting on the same traced function

# - check if the livepatch is in effect

# - reset trace and unload livepatch



start_test "livepatch a traced function and check that the live patch remains in effect"



FUNCTION_NAME="cmdline_proc_show"



trace_function "$FUNCTION_NAME"

load_lp $MOD_LIVEPATCH



if [[ "$(cat /proc/cmdline)" == "$MOD_LIVEPATCH: this has been live patched" ]] ; then

	log "livepatch: ok"

fi



check_traced_functions "$FUNCTION_NAME"



disable_lp $MOD_LIVEPATCH

unload_lp $MOD_LIVEPATCH



check_result "% insmod test_modules/$MOD_LIVEPATCH.ko

livepatch: enabling patch '$MOD_LIVEPATCH'

livepatch: '$MOD_LIVEPATCH': initializing patching transition

livepatch: '$MOD_LIVEPATCH': starting patching transition

livepatch: '$MOD_LIVEPATCH': completing patching transition

livepatch: '$MOD_LIVEPATCH': patching complete

livepatch: ok

% echo 0 > $SYSFS_KLP_DIR/$MOD_LIVEPATCH/enabled

livepatch: '$MOD_LIVEPATCH': initializing unpatching transition

livepatch: '$MOD_LIVEPATCH': starting unpatching transition

livepatch: '$MOD_LIVEPATCH': completing unpatching transition

livepatch: '$MOD_LIVEPATCH': unpatching complete

% rmmod $MOD_LIVEPATCH"



exit 0

tools/testing/selftests/livepatch/test-livepatch.sh

+100 −0
Original line number Diff line number Diff line
@@ -8,6 +8,8 @@ MOD_LIVEPATCH1=test_klp_livepatch 
MOD_LIVEPATCH2=test_klp_syscall

MOD_LIVEPATCH3=test_klp_callbacks_demo

MOD_REPLACE=test_klp_atomic_replace

MOD_TARGET=test_klp_mod_target

MOD_TARGET_PATCH=test_klp_mod_patch



setup_config
@@ -196,4 +198,102 @@ livepatch: '$MOD_REPLACE': unpatching complete 
% rmmod $MOD_REPLACE"





# - load a target module that provides /proc/test_klp_mod_target with

#   original output

# - load a livepatch that patches the target module's show function

# - verify the proc entry returns livepatched output

# - disable and unload the livepatch

# - verify the proc entry returns original output again

# - unload the target module



start_test "module function patching"



load_mod $MOD_TARGET



if [[ "$(cat /proc/$MOD_TARGET)" != "$MOD_TARGET: original output" ]] ; then

	echo -e "FAIL\n\n"

	die "livepatch kselftest(s) failed"

fi



load_lp $MOD_TARGET_PATCH



if [[ "$(cat /proc/$MOD_TARGET)" != "$MOD_TARGET_PATCH: this has been live patched" ]] ; then

	echo -e "FAIL\n\n"

	die "livepatch kselftest(s) failed"

fi



disable_lp $MOD_TARGET_PATCH

unload_lp $MOD_TARGET_PATCH



if [[ "$(cat /proc/$MOD_TARGET)" != "$MOD_TARGET: original output" ]] ; then

	echo -e "FAIL\n\n"

	die "livepatch kselftest(s) failed"

fi



unload_mod $MOD_TARGET



check_result "% insmod test_modules/$MOD_TARGET.ko

$MOD_TARGET: test_klp_mod_target_init

% insmod test_modules/$MOD_TARGET_PATCH.ko

livepatch: enabling patch '$MOD_TARGET_PATCH'

livepatch: '$MOD_TARGET_PATCH': initializing patching transition

livepatch: '$MOD_TARGET_PATCH': starting patching transition

livepatch: '$MOD_TARGET_PATCH': completing patching transition

livepatch: '$MOD_TARGET_PATCH': patching complete

% echo 0 > $SYSFS_KLP_DIR/$MOD_TARGET_PATCH/enabled

livepatch: '$MOD_TARGET_PATCH': initializing unpatching transition

livepatch: '$MOD_TARGET_PATCH': starting unpatching transition

livepatch: '$MOD_TARGET_PATCH': completing unpatching transition

livepatch: '$MOD_TARGET_PATCH': unpatching complete

% rmmod $MOD_TARGET_PATCH

% rmmod $MOD_TARGET

$MOD_TARGET: test_klp_mod_target_exit"





# - load a livepatch that targets a not-yet-loaded module

# - load the target module: klp_module_coming patches it immediately

# - verify the proc entry returns livepatched output

# - disable and unload the livepatch

# - verify the proc entry returns original output again

# - unload the target module



start_test "module function patching (livepatch first)"



load_lp $MOD_TARGET_PATCH

load_mod $MOD_TARGET



if [[ "$(cat /proc/$MOD_TARGET)" != "$MOD_TARGET_PATCH: this has been live patched" ]] ; then

	echo -e "FAIL\n\n"

	die "livepatch kselftest(s) failed"

fi



disable_lp $MOD_TARGET_PATCH

unload_lp $MOD_TARGET_PATCH



if [[ "$(cat /proc/$MOD_TARGET)" != "$MOD_TARGET: original output" ]] ; then

	echo -e "FAIL\n\n"

	die "livepatch kselftest(s) failed"

fi



unload_mod $MOD_TARGET



check_result "% insmod test_modules/$MOD_TARGET_PATCH.ko

livepatch: enabling patch '$MOD_TARGET_PATCH'

livepatch: '$MOD_TARGET_PATCH': initializing patching transition

livepatch: '$MOD_TARGET_PATCH': starting patching transition

livepatch: '$MOD_TARGET_PATCH': completing patching transition

livepatch: '$MOD_TARGET_PATCH': patching complete

% insmod test_modules/$MOD_TARGET.ko

livepatch: applying patch '$MOD_TARGET_PATCH' to loading module '$MOD_TARGET'

$MOD_TARGET: test_klp_mod_target_init

% echo 0 > $SYSFS_KLP_DIR/$MOD_TARGET_PATCH/enabled

livepatch: '$MOD_TARGET_PATCH': initializing unpatching transition

livepatch: '$MOD_TARGET_PATCH': starting unpatching transition

livepatch: '$MOD_TARGET_PATCH': completing unpatching transition

livepatch: '$MOD_TARGET_PATCH': unpatching complete

% rmmod $MOD_TARGET_PATCH

% rmmod $MOD_TARGET

$MOD_TARGET: test_klp_mod_target_exit"





exit 0

tools/testing/selftests/livepatch/test_modules/Makefile

+2 −0
Original line number Diff line number Diff line
@@ -8,6 +8,8 @@ obj-m += test_klp_atomic_replace.o \ 
	test_klp_callbacks_mod.o \

	test_klp_kprobe.o \

	test_klp_livepatch.o \

	test_klp_mod_patch.o \

	test_klp_mod_target.o \

	test_klp_shadow_vars.o \

	test_klp_state.o \

	test_klp_state2.o \

tools/testing/selftests/livepatch/test_modules/test_klp_mod_patch.c

0 → 100644
+53 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0

// Copyright (C) 2026 Pablo Hugen <phugen@redhat.com>



#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt



#include <linux/module.h>

#include <linux/kernel.h>

#include <linux/livepatch.h>

#include <linux/seq_file.h>



static int livepatch_mod_target_show(struct seq_file *m, void *v)

{

	seq_printf(m, "%s: %s\n", THIS_MODULE->name,

		   "this has been live patched");

	return 0;

}



static struct klp_func funcs[] = {

	{

		.old_name = "test_klp_mod_target_show",

		.new_func = livepatch_mod_target_show,

	},

	{},

};



static struct klp_object objs[] = {

	{

		.name = "test_klp_mod_target",

		.funcs = funcs,

	},

	{},

};



static struct klp_patch patch = {

	.mod = THIS_MODULE,

	.objs = objs,

};



static int test_klp_mod_patch_init(void)

{

	return klp_enable_patch(&patch);

}



static void test_klp_mod_patch_exit(void)

{

}



module_init(test_klp_mod_patch_init);

module_exit(test_klp_mod_patch_exit);

MODULE_LICENSE("GPL");

MODULE_INFO(livepatch, "Y");

MODULE_AUTHOR("Pablo Hugen <phugen@redhat.com>");

MODULE_DESCRIPTION("Livepatch test: patch for module-provided function");

tools/testing/selftests/livepatch/test_modules/test_klp_mod_target.c

0 → 100644
+39 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0

// Copyright (C) 2026 Pablo Hugen <phugen@redhat.com>



#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt



#include <linux/module.h>

#include <linux/kernel.h>

#include <linux/proc_fs.h>

#include <linux/seq_file.h>



static struct proc_dir_entry *pde;



static noinline int test_klp_mod_target_show(struct seq_file *m, void *v)

{

	seq_printf(m, "%s: %s\n", THIS_MODULE->name, "original output");

	return 0;

}



static int test_klp_mod_target_init(void)

{

	pr_info("%s\n", __func__);

	pde = proc_create_single("test_klp_mod_target", 0, NULL,

				 test_klp_mod_target_show);

	if (!pde)

		return -ENOMEM;

	return 0;

}



static void test_klp_mod_target_exit(void)

{

	pr_info("%s\n", __func__);

	proc_remove(pde);

}



module_init(test_klp_mod_target_init);

module_exit(test_klp_mod_target_exit);

MODULE_LICENSE("GPL");

MODULE_AUTHOR("Pablo Hugen <phugen@redhat.com>");

MODULE_DESCRIPTION("Livepatch test: target module with proc entry");