[linux-block.git] / lib / test_fprobe.c

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * test_fprobe.c - simple sanity test for fprobe
 */

#include <linux/kernel.h>
#include <linux/fprobe.h>
#include <linux/random.h>
#include <kunit/test.h>

#define div_factor 3

static struct kunit *current_test;

static u32 rand1, entry_val, exit_val;

/* Use indirect calls to avoid inlining the target functions */
static u32 (*target)(u32 value);
static u32 (*target2)(u32 value);
static unsigned long target_ip;
static unsigned long target2_ip;

static noinline u32 fprobe_selftest_target(u32 value)
{
	return (value / div_factor);
}

static noinline u32 fprobe_selftest_target2(u32 value)
{
	return (value / div_factor) + 1;
}

static notrace void fp_entry_handler(struct fprobe *fp, unsigned long ip, struct pt_regs *regs)
{
	KUNIT_EXPECT_FALSE(current_test, preemptible());
	/* This can be called on the fprobe_selftest_target and the fprobe_selftest_target2 */
	if (ip != target_ip)
		KUNIT_EXPECT_EQ(current_test, ip, target2_ip);
	entry_val = (rand1 / div_factor);
}

static notrace void fp_exit_handler(struct fprobe *fp, unsigned long ip, struct pt_regs *regs)
{
	unsigned long ret = regs_return_value(regs);

	KUNIT_EXPECT_FALSE(current_test, preemptible());
	if (ip != target_ip) {
		KUNIT_EXPECT_EQ(current_test, ip, target2_ip);
		KUNIT_EXPECT_EQ(current_test, ret, (rand1 / div_factor) + 1);
	} else
		KUNIT_EXPECT_EQ(current_test, ret, (rand1 / div_factor));
	KUNIT_EXPECT_EQ(current_test, entry_val, (rand1 / div_factor));
	exit_val = entry_val + div_factor;
}

/* Test entry only (no rethook) */
static void test_fprobe_entry(struct kunit *test)
{
	struct fprobe fp_entry = {
		.entry_handler = fp_entry_handler,
	};

	current_test = test;

	/* Before register, unregister should be failed. */
	KUNIT_EXPECT_NE(test, 0, unregister_fprobe(&fp_entry));
	KUNIT_EXPECT_EQ(test, 0, register_fprobe(&fp_entry, "fprobe_selftest_target*", NULL));

	entry_val = 0;
	exit_val = 0;
	target(rand1);
	KUNIT_EXPECT_NE(test, 0, entry_val);
	KUNIT_EXPECT_EQ(test, 0, exit_val);

	entry_val = 0;
	exit_val = 0;
	target2(rand1);
	KUNIT_EXPECT_NE(test, 0, entry_val);
	KUNIT_EXPECT_EQ(test, 0, exit_val);

	KUNIT_EXPECT_EQ(test, 0, unregister_fprobe(&fp_entry));
}

static void test_fprobe(struct kunit *test)
{
	struct fprobe fp = {
		.entry_handler = fp_entry_handler,
		.exit_handler = fp_exit_handler,
	};

	current_test = test;
	KUNIT_EXPECT_EQ(test, 0, register_fprobe(&fp, "fprobe_selftest_target*", NULL));

	entry_val = 0;
	exit_val = 0;
	target(rand1);
	KUNIT_EXPECT_NE(test, 0, entry_val);
	KUNIT_EXPECT_EQ(test, entry_val + div_factor, exit_val);

	entry_val = 0;
	exit_val = 0;
	target2(rand1);
	KUNIT_EXPECT_NE(test, 0, entry_val);
	KUNIT_EXPECT_EQ(test, entry_val + div_factor, exit_val);

	KUNIT_EXPECT_EQ(test, 0, unregister_fprobe(&fp));
}

static void test_fprobe_syms(struct kunit *test)
{
	static const char *syms[] = {"fprobe_selftest_target", "fprobe_selftest_target2"};
	struct fprobe fp = {
		.entry_handler = fp_entry_handler,
		.exit_handler = fp_exit_handler,
	};

	current_test = test;
	KUNIT_EXPECT_EQ(test, 0, register_fprobe_syms(&fp, syms, 2));

	entry_val = 0;
	exit_val = 0;
	target(rand1);
	KUNIT_EXPECT_NE(test, 0, entry_val);
	KUNIT_EXPECT_EQ(test, entry_val + div_factor, exit_val);

	entry_val = 0;
	exit_val = 0;
	target2(rand1);
	KUNIT_EXPECT_NE(test, 0, entry_val);
	KUNIT_EXPECT_EQ(test, entry_val + div_factor, exit_val);

	KUNIT_EXPECT_EQ(test, 0, unregister_fprobe(&fp));
}

static unsigned long get_ftrace_location(void *func)
{
	unsigned long size, addr = (unsigned long)func;

	if (!kallsyms_lookup_size_offset(addr, &size, NULL) || !size)
		return 0;

	return ftrace_location_range(addr, addr + size - 1);
}

static int fprobe_test_init(struct kunit *test)
{
	rand1 = get_random_u32_above(div_factor);
	target = fprobe_selftest_target;
	target2 = fprobe_selftest_target2;
	target_ip = get_ftrace_location(target);
	target2_ip = get_ftrace_location(target2);

	return 0;
}

static struct kunit_case fprobe_testcases[] = {
	KUNIT_CASE(test_fprobe_entry),
	KUNIT_CASE(test_fprobe),
	KUNIT_CASE(test_fprobe_syms),
	{}
};

static struct kunit_suite fprobe_test_suite = {
	.name = "fprobe_test",
	.init = fprobe_test_init,
	.test_cases = fprobe_testcases,
};

kunit_test_suites(&fprobe_test_suite);

MODULE_LICENSE("GPL");
Commit	Line	Data
f4616fab MH	1	// SPDX-License-Identifier: GPL-2.0-or-later
	2	/*
	3	* test_fprobe.c - simple sanity test for fprobe
	4	*/
	5
	6	#include <linux/kernel.h>
	7	#include <linux/fprobe.h>
	8	#include <linux/random.h>
	9	#include <kunit/test.h>
	10
	11	#define div_factor 3
	12
	13	static struct kunit *current_test;
	14
	15	static u32 rand1, entry_val, exit_val;
	16
	17	/* Use indirect calls to avoid inlining the target functions */
	18	static u32 (*target)(u32 value);
	19	static u32 (*target2)(u32 value);
	20	static unsigned long target_ip;
	21	static unsigned long target2_ip;
	22
	23	static noinline u32 fprobe_selftest_target(u32 value)
	24	{
	25	return (value / div_factor);
	26	}
	27
	28	static noinline u32 fprobe_selftest_target2(u32 value)
	29	{
	30	return (value / div_factor) + 1;
	31	}
	32
	33	static notrace void fp_entry_handler(struct fprobe fp, unsigned long ip, struct pt_regs regs)
	34	{
	35	KUNIT_EXPECT_FALSE(current_test, preemptible());
	36	/* This can be called on the fprobe_selftest_target and the fprobe_selftest_target2 */
	37	if (ip != target_ip)
	38	KUNIT_EXPECT_EQ(current_test, ip, target2_ip);
	39	entry_val = (rand1 / div_factor);
	40	}
	41
	42	static notrace void fp_exit_handler(struct fprobe fp, unsigned long ip, struct pt_regs regs)
	43	{
	44	unsigned long ret = regs_return_value(regs);
	45
	46	KUNIT_EXPECT_FALSE(current_test, preemptible());
	47	if (ip != target_ip) {
	48	KUNIT_EXPECT_EQ(current_test, ip, target2_ip);
	49	KUNIT_EXPECT_EQ(current_test, ret, (rand1 / div_factor) + 1);
	50	} else
	51	KUNIT_EXPECT_EQ(current_test, ret, (rand1 / div_factor));
	52	KUNIT_EXPECT_EQ(current_test, entry_val, (rand1 / div_factor));
	53	exit_val = entry_val + div_factor;
	54	}
	55
	56	/* Test entry only (no rethook) */
	57	static void test_fprobe_entry(struct kunit *test)
	58	{
	59	struct fprobe fp_entry = {
	60	.entry_handler = fp_entry_handler,
	61	};
	62
	63	current_test = test;
	64
65	/* Before register, unregister should be failed. */
66	KUNIT_EXPECT_NE(test, 0, unregister_fprobe(&fp_entry));
67	KUNIT_EXPECT_EQ(test, 0, register_fprobe(&fp_entry, "fprobe_selftest_target*", NULL));
68
69	entry_val = 0;
70	exit_val = 0;
71	target(rand1);
72	KUNIT_EXPECT_NE(test, 0, entry_val);
73	KUNIT_EXPECT_EQ(test, 0, exit_val);
74
75	entry_val = 0;
76	exit_val = 0;
77	target2(rand1);
78	KUNIT_EXPECT_NE(test, 0, entry_val);
79	KUNIT_EXPECT_EQ(test, 0, exit_val);
80
81	KUNIT_EXPECT_EQ(test, 0, unregister_fprobe(&fp_entry));
82	}
83
84	static void test_fprobe(struct kunit *test)
85	{
86	struct fprobe fp = {
87	.entry_handler = fp_entry_handler,
88	.exit_handler = fp_exit_handler,
89	};
90
91	current_test = test;
92	KUNIT_EXPECT_EQ(test, 0, register_fprobe(&fp, "fprobe_selftest_target*", NULL));
93
94	entry_val = 0;
95	exit_val = 0;
96	target(rand1);
97	KUNIT_EXPECT_NE(test, 0, entry_val);
98	KUNIT_EXPECT_EQ(test, entry_val + div_factor, exit_val);
99
100	entry_val = 0;
101	exit_val = 0;
102	target2(rand1);
103	KUNIT_EXPECT_NE(test, 0, entry_val);
104	KUNIT_EXPECT_EQ(test, entry_val + div_factor, exit_val);
105
106	KUNIT_EXPECT_EQ(test, 0, unregister_fprobe(&fp));
107	}
108
109	static void test_fprobe_syms(struct kunit *test)
110	{
111	static const char *syms[] = {"fprobe_selftest_target", "fprobe_selftest_target2"};
112	struct fprobe fp = {
113	.entry_handler = fp_entry_handler,
114	.exit_handler = fp_exit_handler,
115	};
116
117	current_test = test;
118	KUNIT_EXPECT_EQ(test, 0, register_fprobe_syms(&fp, syms, 2));
119
120	entry_val = 0;
121	exit_val = 0;
122	target(rand1);
123	KUNIT_EXPECT_NE(test, 0, entry_val);
124	KUNIT_EXPECT_EQ(test, entry_val + div_factor, exit_val);
125
126	entry_val = 0;
127	exit_val = 0;
128	target2(rand1);
129	KUNIT_EXPECT_NE(test, 0, entry_val);
130	KUNIT_EXPECT_EQ(test, entry_val + div_factor, exit_val);
131
132	KUNIT_EXPECT_EQ(test, 0, unregister_fprobe(&fp));
133	}
134
135	static unsigned long get_ftrace_location(void *func)
136	{
137	unsigned long size, addr = (unsigned long)func;
138
139	if (!kallsyms_lookup_size_offset(addr, &size, NULL) \|\| !size)
140	return 0;
141
142	return ftrace_location_range(addr, addr + size - 1);
143	}
144
145	static int fprobe_test_init(struct kunit *test)
146	{
d247aabd	147	rand1 = get_random_u32_above(div_factor);
f4616fab MH	148	target = fprobe_selftest_target;
	149	target2 = fprobe_selftest_target2;
	150	target_ip = get_ftrace_location(target);
	151	target2_ip = get_ftrace_location(target2);
	152
	153	return 0;
	154	}
	155
	156	static struct kunit_case fprobe_testcases[] = {
	157	KUNIT_CASE(test_fprobe_entry),
	158	KUNIT_CASE(test_fprobe),
	159	KUNIT_CASE(test_fprobe_syms),
	160	{}
	161	};
	162
	163	static struct kunit_suite fprobe_test_suite = {
	164	.name = "fprobe_test",
	165	.init = fprobe_test_init,
	166	.test_cases = fprobe_testcases,
	167	};
	168
	169	kunit_test_suites(&fprobe_test_suite);
	170
	171	MODULE_LICENSE("GPL");