372 lines
9.4 KiB
C
372 lines
9.4 KiB
C
// SPDX-License-Identifier: GPL-2.0-or-later
|
|
/*
|
|
* test_kprobes.c - simple sanity test for *probes
|
|
*
|
|
* Copyright IBM Corp. 2008
|
|
*/
|
|
|
|
#include <linux/kernel.h>
|
|
#include <linux/kprobes.h>
|
|
#include <linux/random.h>
|
|
#include <kunit/test.h>
|
|
|
|
#define div_factor 3
|
|
|
|
static u32 rand1, preh_val, posth_val;
|
|
static u32 (*target)(u32 value);
|
|
static u32 (*target2)(u32 value);
|
|
static struct kunit *current_test;
|
|
|
|
static unsigned long (*internal_target)(void);
|
|
static unsigned long (*stacktrace_target)(void);
|
|
static unsigned long (*stacktrace_driver)(void);
|
|
static unsigned long target_return_address[2];
|
|
|
|
static noinline u32 kprobe_target(u32 value)
|
|
{
|
|
return (value / div_factor);
|
|
}
|
|
|
|
static int kp_pre_handler(struct kprobe *p, struct pt_regs *regs)
|
|
{
|
|
KUNIT_EXPECT_FALSE(current_test, preemptible());
|
|
preh_val = (rand1 / div_factor);
|
|
return 0;
|
|
}
|
|
|
|
static void kp_post_handler(struct kprobe *p, struct pt_regs *regs,
|
|
unsigned long flags)
|
|
{
|
|
KUNIT_EXPECT_FALSE(current_test, preemptible());
|
|
KUNIT_EXPECT_EQ(current_test, preh_val, (rand1 / div_factor));
|
|
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 void test_kprobe(struct kunit *test)
|
|
{
|
|
current_test = test;
|
|
KUNIT_EXPECT_EQ(test, 0, register_kprobe(&kp));
|
|
target(rand1);
|
|
unregister_kprobe(&kp);
|
|
KUNIT_EXPECT_NE(test, 0, preh_val);
|
|
KUNIT_EXPECT_NE(test, 0, posth_val);
|
|
}
|
|
|
|
static noinline u32 kprobe_target2(u32 value)
|
|
{
|
|
return (value / div_factor) + 1;
|
|
}
|
|
|
|
static noinline unsigned long kprobe_stacktrace_internal_target(void)
|
|
{
|
|
if (!target_return_address[0])
|
|
target_return_address[0] = (unsigned long)__builtin_return_address(0);
|
|
return target_return_address[0];
|
|
}
|
|
|
|
static noinline unsigned long kprobe_stacktrace_target(void)
|
|
{
|
|
if (!target_return_address[1])
|
|
target_return_address[1] = (unsigned long)__builtin_return_address(0);
|
|
|
|
if (internal_target)
|
|
internal_target();
|
|
|
|
return target_return_address[1];
|
|
}
|
|
|
|
static noinline unsigned long kprobe_stacktrace_driver(void)
|
|
{
|
|
if (stacktrace_target)
|
|
stacktrace_target();
|
|
|
|
/* This is for preventing inlining the function */
|
|
return (unsigned long)__builtin_return_address(0);
|
|
}
|
|
|
|
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)
|
|
{
|
|
KUNIT_EXPECT_EQ(current_test, preh_val, (rand1 / div_factor) + 1);
|
|
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 void test_kprobes(struct kunit *test)
|
|
{
|
|
struct kprobe *kps[2] = {&kp, &kp2};
|
|
|
|
current_test = test;
|
|
|
|
/* addr and flags should be cleard for reusing kprobe. */
|
|
kp.addr = NULL;
|
|
kp.flags = 0;
|
|
|
|
KUNIT_EXPECT_EQ(test, 0, register_kprobes(kps, 2));
|
|
preh_val = 0;
|
|
posth_val = 0;
|
|
target(rand1);
|
|
|
|
KUNIT_EXPECT_NE(test, 0, preh_val);
|
|
KUNIT_EXPECT_NE(test, 0, posth_val);
|
|
|
|
preh_val = 0;
|
|
posth_val = 0;
|
|
target2(rand1);
|
|
|
|
KUNIT_EXPECT_NE(test, 0, preh_val);
|
|
KUNIT_EXPECT_NE(test, 0, posth_val);
|
|
unregister_kprobes(kps, 2);
|
|
}
|
|
|
|
#ifdef CONFIG_KRETPROBES
|
|
static u32 krph_val;
|
|
|
|
static int entry_handler(struct kretprobe_instance *ri, struct pt_regs *regs)
|
|
{
|
|
KUNIT_EXPECT_FALSE(current_test, preemptible());
|
|
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);
|
|
|
|
KUNIT_EXPECT_FALSE(current_test, preemptible());
|
|
KUNIT_EXPECT_EQ(current_test, ret, rand1 / div_factor);
|
|
KUNIT_EXPECT_NE(current_test, krph_val, 0);
|
|
krph_val = rand1;
|
|
return 0;
|
|
}
|
|
|
|
static struct kretprobe rp = {
|
|
.handler = return_handler,
|
|
.entry_handler = entry_handler,
|
|
.kp.symbol_name = "kprobe_target"
|
|
};
|
|
|
|
static void test_kretprobe(struct kunit *test)
|
|
{
|
|
current_test = test;
|
|
KUNIT_EXPECT_EQ(test, 0, register_kretprobe(&rp));
|
|
target(rand1);
|
|
unregister_kretprobe(&rp);
|
|
KUNIT_EXPECT_EQ(test, krph_val, rand1);
|
|
}
|
|
|
|
static int return_handler2(struct kretprobe_instance *ri, struct pt_regs *regs)
|
|
{
|
|
unsigned long ret = regs_return_value(regs);
|
|
|
|
KUNIT_EXPECT_EQ(current_test, ret, (rand1 / div_factor) + 1);
|
|
KUNIT_EXPECT_NE(current_test, krph_val, 0);
|
|
krph_val = rand1;
|
|
return 0;
|
|
}
|
|
|
|
static struct kretprobe rp2 = {
|
|
.handler = return_handler2,
|
|
.entry_handler = entry_handler,
|
|
.kp.symbol_name = "kprobe_target2"
|
|
};
|
|
|
|
static void test_kretprobes(struct kunit *test)
|
|
{
|
|
struct kretprobe *rps[2] = {&rp, &rp2};
|
|
|
|
current_test = test;
|
|
/* addr and flags should be cleard for reusing kprobe. */
|
|
rp.kp.addr = NULL;
|
|
rp.kp.flags = 0;
|
|
KUNIT_EXPECT_EQ(test, 0, register_kretprobes(rps, 2));
|
|
|
|
krph_val = 0;
|
|
target(rand1);
|
|
KUNIT_EXPECT_EQ(test, krph_val, rand1);
|
|
|
|
krph_val = 0;
|
|
target2(rand1);
|
|
KUNIT_EXPECT_EQ(test, krph_val, rand1);
|
|
unregister_kretprobes(rps, 2);
|
|
}
|
|
|
|
#ifdef CONFIG_ARCH_CORRECT_STACKTRACE_ON_KRETPROBE
|
|
#define STACK_BUF_SIZE 16
|
|
static unsigned long stack_buf[STACK_BUF_SIZE];
|
|
|
|
static int stacktrace_return_handler(struct kretprobe_instance *ri, struct pt_regs *regs)
|
|
{
|
|
unsigned long retval = regs_return_value(regs);
|
|
int i, ret;
|
|
|
|
KUNIT_EXPECT_FALSE(current_test, preemptible());
|
|
KUNIT_EXPECT_EQ(current_test, retval, target_return_address[1]);
|
|
|
|
/*
|
|
* Test stacktrace inside the kretprobe handler, this will involves
|
|
* kretprobe trampoline, but must include correct return address
|
|
* of the target function.
|
|
*/
|
|
ret = stack_trace_save(stack_buf, STACK_BUF_SIZE, 0);
|
|
KUNIT_EXPECT_NE(current_test, ret, 0);
|
|
|
|
for (i = 0; i < ret; i++) {
|
|
if (stack_buf[i] == target_return_address[1])
|
|
break;
|
|
}
|
|
KUNIT_EXPECT_NE(current_test, i, ret);
|
|
|
|
#if !IS_MODULE(CONFIG_KPROBES_SANITY_TEST)
|
|
/*
|
|
* Test stacktrace from pt_regs at the return address. Thus the stack
|
|
* trace must start from the target return address.
|
|
*/
|
|
ret = stack_trace_save_regs(regs, stack_buf, STACK_BUF_SIZE, 0);
|
|
KUNIT_EXPECT_NE(current_test, ret, 0);
|
|
KUNIT_EXPECT_EQ(current_test, stack_buf[0], target_return_address[1]);
|
|
#endif
|
|
|
|
return 0;
|
|
}
|
|
|
|
static struct kretprobe rp3 = {
|
|
.handler = stacktrace_return_handler,
|
|
.kp.symbol_name = "kprobe_stacktrace_target"
|
|
};
|
|
|
|
static void test_stacktrace_on_kretprobe(struct kunit *test)
|
|
{
|
|
unsigned long myretaddr = (unsigned long)__builtin_return_address(0);
|
|
|
|
current_test = test;
|
|
rp3.kp.addr = NULL;
|
|
rp3.kp.flags = 0;
|
|
|
|
/*
|
|
* Run the stacktrace_driver() to record correct return address in
|
|
* stacktrace_target() and ensure stacktrace_driver() call is not
|
|
* inlined by checking the return address of stacktrace_driver()
|
|
* and the return address of this function is different.
|
|
*/
|
|
KUNIT_ASSERT_NE(test, myretaddr, stacktrace_driver());
|
|
|
|
KUNIT_ASSERT_EQ(test, 0, register_kretprobe(&rp3));
|
|
KUNIT_ASSERT_NE(test, myretaddr, stacktrace_driver());
|
|
unregister_kretprobe(&rp3);
|
|
}
|
|
|
|
static int stacktrace_internal_return_handler(struct kretprobe_instance *ri, struct pt_regs *regs)
|
|
{
|
|
unsigned long retval = regs_return_value(regs);
|
|
int i, ret;
|
|
|
|
KUNIT_EXPECT_FALSE(current_test, preemptible());
|
|
KUNIT_EXPECT_EQ(current_test, retval, target_return_address[0]);
|
|
|
|
/*
|
|
* Test stacktrace inside the kretprobe handler for nested case.
|
|
* The unwinder will find the kretprobe_trampoline address on the
|
|
* return address, and kretprobe must solve that.
|
|
*/
|
|
ret = stack_trace_save(stack_buf, STACK_BUF_SIZE, 0);
|
|
KUNIT_EXPECT_NE(current_test, ret, 0);
|
|
|
|
for (i = 0; i < ret - 1; i++) {
|
|
if (stack_buf[i] == target_return_address[0]) {
|
|
KUNIT_EXPECT_EQ(current_test, stack_buf[i + 1], target_return_address[1]);
|
|
break;
|
|
}
|
|
}
|
|
KUNIT_EXPECT_NE(current_test, i, ret);
|
|
|
|
#if !IS_MODULE(CONFIG_KPROBES_SANITY_TEST)
|
|
/* Ditto for the regs version. */
|
|
ret = stack_trace_save_regs(regs, stack_buf, STACK_BUF_SIZE, 0);
|
|
KUNIT_EXPECT_NE(current_test, ret, 0);
|
|
KUNIT_EXPECT_EQ(current_test, stack_buf[0], target_return_address[0]);
|
|
KUNIT_EXPECT_EQ(current_test, stack_buf[1], target_return_address[1]);
|
|
#endif
|
|
|
|
return 0;
|
|
}
|
|
|
|
static struct kretprobe rp4 = {
|
|
.handler = stacktrace_internal_return_handler,
|
|
.kp.symbol_name = "kprobe_stacktrace_internal_target"
|
|
};
|
|
|
|
static void test_stacktrace_on_nested_kretprobe(struct kunit *test)
|
|
{
|
|
unsigned long myretaddr = (unsigned long)__builtin_return_address(0);
|
|
struct kretprobe *rps[2] = {&rp3, &rp4};
|
|
|
|
current_test = test;
|
|
rp3.kp.addr = NULL;
|
|
rp3.kp.flags = 0;
|
|
|
|
//KUNIT_ASSERT_NE(test, myretaddr, stacktrace_driver());
|
|
|
|
KUNIT_ASSERT_EQ(test, 0, register_kretprobes(rps, 2));
|
|
KUNIT_ASSERT_NE(test, myretaddr, stacktrace_driver());
|
|
unregister_kretprobes(rps, 2);
|
|
}
|
|
#endif /* CONFIG_ARCH_CORRECT_STACKTRACE_ON_KRETPROBE */
|
|
|
|
#endif /* CONFIG_KRETPROBES */
|
|
|
|
static int kprobes_test_init(struct kunit *test)
|
|
{
|
|
target = kprobe_target;
|
|
target2 = kprobe_target2;
|
|
stacktrace_target = kprobe_stacktrace_target;
|
|
internal_target = kprobe_stacktrace_internal_target;
|
|
stacktrace_driver = kprobe_stacktrace_driver;
|
|
|
|
do {
|
|
rand1 = get_random_u32();
|
|
} while (rand1 <= div_factor);
|
|
return 0;
|
|
}
|
|
|
|
static struct kunit_case kprobes_testcases[] = {
|
|
KUNIT_CASE(test_kprobe),
|
|
KUNIT_CASE(test_kprobes),
|
|
#ifdef CONFIG_KRETPROBES
|
|
KUNIT_CASE(test_kretprobe),
|
|
KUNIT_CASE(test_kretprobes),
|
|
#ifdef CONFIG_ARCH_CORRECT_STACKTRACE_ON_KRETPROBE
|
|
KUNIT_CASE(test_stacktrace_on_kretprobe),
|
|
KUNIT_CASE(test_stacktrace_on_nested_kretprobe),
|
|
#endif
|
|
#endif
|
|
{}
|
|
};
|
|
|
|
static struct kunit_suite kprobes_test_suite = {
|
|
.name = "kprobes_test",
|
|
.init = kprobes_test_init,
|
|
.test_cases = kprobes_testcases,
|
|
};
|
|
|
|
kunit_test_suites(&kprobes_test_suite);
|
|
|
|
MODULE_LICENSE("GPL");
|