diff options
Diffstat (limited to 'arch/arm/kernel/kprobes-test.c')
-rw-r--r-- | arch/arm/kernel/kprobes-test.c | 340 |
1 files changed, 340 insertions, 0 deletions
diff --git a/arch/arm/kernel/kprobes-test.c b/arch/arm/kernel/kprobes-test.c new file mode 100644 index 000000000000..9fff0448c320 --- /dev/null +++ b/arch/arm/kernel/kprobes-test.c @@ -0,0 +1,340 @@ +/* + * arch/arm/kernel/kprobes-test.c + * + * Copyright (C) 2011 Jon Medhurst <tixy@yxit.co.uk>. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/kprobes.h> + +#include "kprobes.h" + + +/* + * Test basic API + */ + +static bool test_regs_ok; +static int test_func_instance; +static int pre_handler_called; +static int post_handler_called; +static int jprobe_func_called; +static int kretprobe_handler_called; + +#define FUNC_ARG1 0x12345678 +#define FUNC_ARG2 0xabcdef + + +#ifndef CONFIG_THUMB2_KERNEL + +long arm_func(long r0, long r1); + +static void __used __naked __arm_kprobes_test_func(void) +{ + __asm__ __volatile__ ( + ".arm \n\t" + ".type arm_func, %%function \n\t" + "arm_func: \n\t" + "adds r0, r0, r1 \n\t" + "bx lr \n\t" + ".code "NORMAL_ISA /* Back to Thumb if necessary */ + : : : "r0", "r1", "cc" + ); +} + +#else /* CONFIG_THUMB2_KERNEL */ + +long thumb16_func(long r0, long r1); +long thumb32even_func(long r0, long r1); +long thumb32odd_func(long r0, long r1); + +static void __used __naked __thumb_kprobes_test_funcs(void) +{ + __asm__ __volatile__ ( + ".type thumb16_func, %%function \n\t" + "thumb16_func: \n\t" + "adds.n r0, r0, r1 \n\t" + "bx lr \n\t" + + ".align \n\t" + ".type thumb32even_func, %%function \n\t" + "thumb32even_func: \n\t" + "adds.w r0, r0, r1 \n\t" + "bx lr \n\t" + + ".align \n\t" + "nop.n \n\t" + ".type thumb32odd_func, %%function \n\t" + "thumb32odd_func: \n\t" + "adds.w r0, r0, r1 \n\t" + "bx lr \n\t" + + : : : "r0", "r1", "cc" + ); +} + +#endif /* CONFIG_THUMB2_KERNEL */ + + +static int call_test_func(long (*func)(long, long), bool check_test_regs) +{ + long ret; + + ++test_func_instance; + test_regs_ok = false; + + ret = (*func)(FUNC_ARG1, FUNC_ARG2); + if (ret != FUNC_ARG1 + FUNC_ARG2) { + pr_err("FAIL: call_test_func: func returned %lx\n", ret); + return false; + } + + if (check_test_regs && !test_regs_ok) { + pr_err("FAIL: test regs not OK\n"); + return false; + } + + return true; +} + +static int __kprobes pre_handler(struct kprobe *p, struct pt_regs *regs) +{ + pre_handler_called = test_func_instance; + if (regs->ARM_r0 == FUNC_ARG1 && regs->ARM_r1 == FUNC_ARG2) + test_regs_ok = true; + return 0; +} + +static void __kprobes post_handler(struct kprobe *p, struct pt_regs *regs, + unsigned long flags) +{ + post_handler_called = test_func_instance; + if (regs->ARM_r0 != FUNC_ARG1 + FUNC_ARG2 || regs->ARM_r1 != FUNC_ARG2) + test_regs_ok = false; +} + +static struct kprobe the_kprobe = { + .addr = 0, + .pre_handler = pre_handler, + .post_handler = post_handler +}; + +static int test_kprobe(long (*func)(long, long)) +{ + int ret; + + the_kprobe.addr = (kprobe_opcode_t *)func; + ret = register_kprobe(&the_kprobe); + if (ret < 0) { + pr_err("FAIL: register_kprobe failed with %d\n", ret); + return ret; + } + + ret = call_test_func(func, true); + + unregister_kprobe(&the_kprobe); + the_kprobe.flags = 0; /* Clear disable flag to allow reuse */ + + if (!ret) + return -EINVAL; + if (pre_handler_called != test_func_instance) { + pr_err("FAIL: kprobe pre_handler not called\n"); + return -EINVAL; + } + if (post_handler_called != test_func_instance) { + pr_err("FAIL: kprobe post_handler not called\n"); + return -EINVAL; + } + if (!call_test_func(func, false)) + return -EINVAL; + if (pre_handler_called == test_func_instance || + post_handler_called == test_func_instance) { + pr_err("FAIL: probe called after unregistering\n"); + return -EINVAL; + } + + return 0; +} + +static void __kprobes jprobe_func(long r0, long r1) +{ + jprobe_func_called = test_func_instance; + if (r0 == FUNC_ARG1 && r1 == FUNC_ARG2) + test_regs_ok = true; + jprobe_return(); +} + +static struct jprobe the_jprobe = { + .entry = jprobe_func, +}; + +static int test_jprobe(long (*func)(long, long)) +{ + int ret; + + the_jprobe.kp.addr = (kprobe_opcode_t *)func; + ret = register_jprobe(&the_jprobe); + if (ret < 0) { + pr_err("FAIL: register_jprobe failed with %d\n", ret); + return ret; + } + + ret = call_test_func(func, true); + + unregister_jprobe(&the_jprobe); + the_jprobe.kp.flags = 0; /* Clear disable flag to allow reuse */ + + if (!ret) + return -EINVAL; + if (jprobe_func_called != test_func_instance) { + pr_err("FAIL: jprobe handler function not called\n"); + return -EINVAL; + } + if (!call_test_func(func, false)) + return -EINVAL; + if (jprobe_func_called == test_func_instance) { + pr_err("FAIL: probe called after unregistering\n"); + return -EINVAL; + } + + return 0; +} + +static int __kprobes +kretprobe_handler(struct kretprobe_instance *ri, struct pt_regs *regs) +{ + kretprobe_handler_called = test_func_instance; + if (regs_return_value(regs) == FUNC_ARG1 + FUNC_ARG2) + test_regs_ok = true; + return 0; +} + +static struct kretprobe the_kretprobe = { + .handler = kretprobe_handler, +}; + +static int test_kretprobe(long (*func)(long, long)) +{ + int ret; + + the_kretprobe.kp.addr = (kprobe_opcode_t *)func; + ret = register_kretprobe(&the_kretprobe); + if (ret < 0) { + pr_err("FAIL: register_kretprobe failed with %d\n", ret); + return ret; + } + + ret = call_test_func(func, true); + + unregister_kretprobe(&the_kretprobe); + the_kretprobe.kp.flags = 0; /* Clear disable flag to allow reuse */ + + if (!ret) + return -EINVAL; + if (kretprobe_handler_called != test_func_instance) { + pr_err("FAIL: kretprobe handler not called\n"); + return -EINVAL; + } + if (!call_test_func(func, false)) + return -EINVAL; + if (jprobe_func_called == test_func_instance) { + pr_err("FAIL: kretprobe called after unregistering\n"); + return -EINVAL; + } + + return 0; +} + +static int run_api_tests(long (*func)(long, long)) +{ + int ret; + + pr_info(" kprobe\n"); + ret = test_kprobe(func); + if (ret < 0) + return ret; + + pr_info(" jprobe\n"); + ret = test_jprobe(func); + if (ret < 0) + return ret; + + pr_info(" kretprobe\n"); + ret = test_kretprobe(func); + if (ret < 0) + return ret; + + return 0; +} + + +/* + * Top level test functions + */ + +static int __init run_all_tests(void) +{ + int ret = 0; + + pr_info("Begining kprobe tests...\n"); + +#ifndef CONFIG_THUMB2_KERNEL + + pr_info("Probe ARM code\n"); + ret = run_api_tests(arm_func); + if (ret) + goto out; + +#else /* CONFIG_THUMB2_KERNEL */ + + pr_info("Probe 16-bit Thumb code\n"); + ret = run_api_tests(thumb16_func); + if (ret) + goto out; + + pr_info("Probe 32-bit Thumb code, even halfword\n"); + ret = run_api_tests(thumb32even_func); + if (ret) + goto out; + + pr_info("Probe 32-bit Thumb code, odd halfword\n"); + ret = run_api_tests(thumb32odd_func); + if (ret) + goto out; + +#endif + +out: + if (ret == 0) + pr_info("Finished kprobe tests OK\n"); + else + pr_err("kprobe tests failed\n"); + + return ret; +} + + +/* + * Module setup + */ + +#ifdef MODULE + +static void __exit kprobe_test_exit(void) +{ +} + +module_init(run_all_tests) +module_exit(kprobe_test_exit) +MODULE_LICENSE("GPL"); + +#else /* !MODULE */ + +late_initcall(run_all_tests); + +#endif |