/*
* test_kprobes.c - simple sanity test for *probes
*
* Copyright IBM Corp. 2008
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it would be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
* the GNU General Public License for more details.
*/
#include <linux/kernel.h>
#include <linux/kprobes.h>
#include <linux/random.h>
#define div_factor 3
static u32 rand1, preh_val, posth_val, jph_val;
static int errors, handler_errors, num_tests;
static u32 (*target)(u32 value);
static u32 (*target2)(u32 value);
static noinline u32 kprobe_target(u32 value)
{
return (value / div_factor);
}
static int kp_pre_handler(struct kprobe *p, struct pt_regs *regs)
{
preh_val = (rand1 / div_factor);
return 0;
}
static void kp_post_handler(struct kprobe *p, struct pt_regs *regs,
unsigned long flags)
{
if (preh_val != (rand1 / div_factor)) {
handler_errors++;
printk(KERN_ERR "Kprobe smoke test failed: "
"incorrect value in post_handler\n");
}
posth_val = preh_val + div_factor;
}
static struct kprobe kp = {
.symbol_name = "kprobe_target",
.pre_handler = kp_pre_handler,
.post_handler = kp_post_handler
};
static int test_kprobe(void)
{
int ret;
ret = register_kprobe(&kp);
if (ret < 0) {
printk(KERN_ERR "Kprobe smoke test failed: "
"register_kprobe returned %d\n", ret);
return ret;
}
ret = target(rand1);
unregister_kprobe(&kp);
if (preh_val == 0) {
printk(KERN_ERR "Kprobe smoke test failed: "
"kprobe pre_handler not called\n");
handler_errors++;
}
if (posth_val == 0) {
printk(KERN_ERR "Kprobe smoke test failed: "
"kprobe post_handler not called\n");
handler_errors++;
}
return 0;
}
static noinline u32 kprobe_target2(u32 value)
{
return (value / div_factor) + 1;
}
static int kp_pre_handler2(struct kprobe *p, struct pt_regs *regs)
{
preh_val = (rand1 / div_factor) + 1;
return 0;
}
static void kp_post_handler2(struct kprobe *p, struct pt_regs *regs,
unsigned long flags)
{
if (preh_val != (rand1 / div_factor) + 1) {
handler_errors++;
printk(KERN_ERR "Kprobe smoke test failed: "
"incorrect value in post_handler2\n");
}
posth_val = preh_val + div_factor;
}
static struct kprobe kp2 = {
.symbol_name = "kprobe_target2",
.pre_handler = kp_pre_handler2,
.post_handler = kp_post_handler2
};
static int test_kprobes(void)
{
int ret;
struct kprobe *kps[2] = {&kp, &kp2};
kp.addr = 0; /* addr should be cleard for reusing kprobe. */
ret = register_kprobes(kps, 2);
if (ret < 0) {
printk(KERN_ERR "Kprobe smoke test failed: "
"register_kprobes returned %d\n", ret);
return ret;
}
preh_val = 0;
posth_val = 0;
ret = target(rand1);
if (preh_val == 0) {
printk(KERN_ERR "Kprobe smoke test failed: "
"kprobe pre_handler not called\n");
handler_errors++;
}
if (posth_val == 0) {
printk(KERN_ERR "Kprobe smoke test failed: "
"kprobe post_handler not called\n");
handler_errors++;
}
preh_val = 0;
posth_val = 0;
ret = target2(rand1);
if (preh_val == 0) {
printk(KERN_ERR "Kprobe smoke test failed: "
"kprobe pre_handler2 not called\n");
handler_errors++;
}
if (posth_val == 0) {
printk(KERN_ERR "Kprobe smoke test failed: "
"kprobe post_handler2 not called\n");
handler_errors++;
}
unregister_kprobes(kps, 2);
return 0;
}
static u32 j_kprobe_target(u32 value)
{
if (value != rand1) {
handler_errors++;
printk(KERN_ERR "Kprobe smoke test failed: "
"incorrect value in jprobe handler\n");
}
jph_val = rand1;
jprobe_return();
return 0;
}
static struct jprobe jp = {
.entry = j_kprobe_target,
.kp.symbol_name = "kprobe_target"
};
static int test_jprobe(void)
{
int ret;
ret = register_jprobe(&jp);
if (ret < 0) {
printk(KERN_ERR "Kprobe smoke test failed: "
"register_jprobe returned %d\n", ret);
return ret;
}
ret = target(rand1);
unregister_jprobe(&jp);
if (jph_val == 0) {
printk(KERN_ERR "Kprobe smoke test failed: "
"jprobe handler not called\n");
handler_errors++;
}
return 0;
}
static struct jprobe jp2 = {
.entry = j_kprobe_target,
.kp.symbol_name = "kprobe_target2"
};
static int test_jprobes(void)
{
int ret;
struct jprobe *jps[2] = {&jp, &jp2};
jp.kp.addr = 0; /* addr should be cleard for reusing kprobe. */
ret = register_jprobes(jps, 2);
if (ret < 0) {
printk(KERN_ERR "Kprobe smoke test failed: "
"register_jprobes returned %d\n", ret);
return ret;
}
jph_val = 0;
ret = target(rand1);
if (jph_val == 0) {
printk(KERN_ERR "Kprobe smoke test failed: "
"jprobe handler not called\n");
handler_errors++;
}
jph_val = 0;
ret = target2(rand1);
if (jph_val == 0) {
printk(KERN_ERR "Kprobe smoke test failed: "
"jprobe handler2 not called\n");
handler_errors++;
}
unregister_jprobes(jps, 2);
return 0;
}
#ifdef CONFIG_KRETPROBES
static u32 krph_val;
static int entry_handler(struct kretprobe_instance *ri, struct pt_regs *regs)
{
krph_val = (rand1 / div_factor);
return 0;
}
static int return_handler(struct kretprobe_instance *ri, struct pt_regs *regs)
{
unsigned long ret = regs_return_value(regs);
if (ret != (rand1 / div_factor)) {
handler_errors++;
printk(KERN_ERR "Kprobe smoke test failed: "
"incorrect value in kretprobe handler\n");
}
if (krph_val == 0) {
handler_errors++;
printk(KERN_ERR "Kprobe smoke test failed: "
"call to kretprobe entry handler failed\n");
}
krph_val = rand1;
return 0;
}
static struct kretprobe rp = {
.handler = return_handler,
.entry_handler = entry_handler,
.kp.symbol_name = "kprobe_target"
};
static int test_kretprobe(void)
{
int ret;
ret = register_kretprobe(&rp);
if (ret < 0) {
printk(KERN_ERR "Kprobe smoke test failed: "
"register_kretprobe returned %d\n", ret);
return ret;
}
ret = target(rand1);
unregister_kretprobe(&rp);
if (krph_val != rand1) {
printk(KERN_ERR "Kprobe smoke test failed: "
"kretprobe handler not called\n");
handler_errors++;
}
return 0;
}
static int return_handler2(struct kretprobe_instance *ri, struct pt_regs *regs)
{
unsigned long ret = regs_return_value(regs);
if (ret != (rand1 / div_factor) + 1) {
handler_errors++;
printk(KERN_ERR "Kprobe smoke test failed: "
"incorrect value in kretprobe handler2\n");
}
if (krph_val == 0) {
handler_errors++;
printk(KERN_ERR "Kprobe smoke test failed: "
"call to kretprobe entry handler failed\n");
}
krph_val = rand1;
return 0;
}
static struct kretprobe rp2 = {
.handler = return_handler2,
.entry_handler = entry_handler,
.kp.symbol_name = "kprobe_target2"
};
static int test_kretprobes(void)
{
int ret;
struct kretprobe *rps[2] = {&rp, &rp2};
rp.kp.addr = 0; /* addr should be cleard for reusing kprobe. */
ret = register_kretprobes(rps, 2);
if (ret < 0) {
printk(KERN_ERR "Kprobe smoke test failed: "
"register_kretprobe returned %d\n", ret);
return ret;
}
krph_val = 0;
ret = target(rand1);
if (krph_val != rand1) {
printk(KERN_ERR "Kprobe smoke test failed: "
"kretprobe handler not called\n");
handler_errors++;
}
krph_val = 0;
ret = target2(rand1);
if (krph_val != rand1) {
printk(KERN_ERR "Kprobe smoke test failed: "
"kretprobe handler2 not called\n");
handler_errors++;
}
unregister_kretprobes(rps, 2);
return 0;
}
#endif /* CONFIG_KRETPROBES */
int init_test_probes(void)
{
int ret;
target = kprobe_target;
target2 = kprobe_target2;
do {
rand1 = random32();
} while (rand1 <= div_factor);
printk(KERN_INFO "Kprobe smoke test started\n");
num_tests++;
ret = test_kprobe();
if (ret < 0)
errors++;
num_tests++;
ret = test_kprobes();
if (ret < 0)
errors++;
num_tests++;
ret = test_jprobe();
if (ret < 0)
errors++;
num_tests++;
ret = test_jprobes();
if (ret < 0)
errors++;
#ifdef CONFIG_KRETPROBES
num_tests++;
ret = test_kretprobe();
if (ret < 0)
errors++;
num_tests++;
ret = test_kretprobes();
if (ret < 0)
errors++;
#endif /* CONFIG_KRETPROBES */
if (errors)
printk(KERN_ERR "BUG: Kprobe smoke test: %d out of "
"%d tests failed\n", errors, num_tests);
else if (handler_errors)
printk(KERN_ERR "BUG: Kprobe smoke test: %d error(s) "
"running handlers\n", handler_errors);
else
printk(KERN_INFO "Kprobe smoke test passed successfully\n");
return 0;
}
