1d2912cb1SThomas Gleixner // SPDX-License-Identifier: GPL-2.0-only 2fca08f32SWang Nan /* 3fca08f32SWang Nan * arch/arm/kernel/kprobes-test.c 4fca08f32SWang Nan * 5fca08f32SWang Nan * Copyright (C) 2011 Jon Medhurst <tixy@yxit.co.uk>. 6fca08f32SWang Nan */ 7fca08f32SWang Nan 8fca08f32SWang Nan /* 9fca08f32SWang Nan * This file contains test code for ARM kprobes. 10fca08f32SWang Nan * 11fca08f32SWang Nan * The top level function run_all_tests() executes tests for all of the 12fca08f32SWang Nan * supported instruction sets: ARM, 16-bit Thumb, and 32-bit Thumb. These tests 13fca08f32SWang Nan * fall into two categories; run_api_tests() checks basic functionality of the 14fca08f32SWang Nan * kprobes API, and run_test_cases() is a comprehensive test for kprobes 15fca08f32SWang Nan * instruction decoding and simulation. 16fca08f32SWang Nan * 17fca08f32SWang Nan * run_test_cases() first checks the kprobes decoding table for self consistency 18fca08f32SWang Nan * (using table_test()) then executes a series of test cases for each of the CPU 19fca08f32SWang Nan * instruction forms. coverage_start() and coverage_end() are used to verify 20fca08f32SWang Nan * that these test cases cover all of the possible combinations of instructions 21fca08f32SWang Nan * described by the kprobes decoding tables. 22fca08f32SWang Nan * 23fca08f32SWang Nan * The individual test cases are in kprobes-test-arm.c and kprobes-test-thumb.c 24fca08f32SWang Nan * which use the macros defined in kprobes-test.h. The rest of this 25fca08f32SWang Nan * documentation will describe the operation of the framework used by these 26fca08f32SWang Nan * test cases. 27fca08f32SWang Nan */ 28fca08f32SWang Nan 29fca08f32SWang Nan /* 30fca08f32SWang Nan * TESTING METHODOLOGY 31fca08f32SWang Nan * ------------------- 32fca08f32SWang Nan * 33fca08f32SWang Nan * The methodology used to test an ARM instruction 'test_insn' is to use 34fca08f32SWang Nan * inline assembler like: 35fca08f32SWang Nan * 36fca08f32SWang Nan * test_before: nop 37fca08f32SWang Nan * test_case: test_insn 38fca08f32SWang Nan * test_after: nop 39fca08f32SWang Nan * 40fca08f32SWang Nan * When the test case is run a kprobe is placed of each nop. The 41fca08f32SWang Nan * post-handler of the test_before probe is used to modify the saved CPU 42fca08f32SWang Nan * register context to that which we require for the test case. The 43fca08f32SWang Nan * pre-handler of the of the test_after probe saves a copy of the CPU 44fca08f32SWang Nan * register context. In this way we can execute test_insn with a specific 45fca08f32SWang Nan * register context and see the results afterwards. 46fca08f32SWang Nan * 47fca08f32SWang Nan * To actually test the kprobes instruction emulation we perform the above 48fca08f32SWang Nan * step a second time but with an additional kprobe on the test_case 49fca08f32SWang Nan * instruction itself. If the emulation is accurate then the results seen 50fca08f32SWang Nan * by the test_after probe will be identical to the first run which didn't 51fca08f32SWang Nan * have a probe on test_case. 52fca08f32SWang Nan * 53fca08f32SWang Nan * Each test case is run several times with a variety of variations in the 54fca08f32SWang Nan * flags value of stored in CPSR, and for Thumb code, different ITState. 55fca08f32SWang Nan * 56fca08f32SWang Nan * For instructions which can modify PC, a second test_after probe is used 57fca08f32SWang Nan * like this: 58fca08f32SWang Nan * 59fca08f32SWang Nan * test_before: nop 60fca08f32SWang Nan * test_case: test_insn 61fca08f32SWang Nan * test_after: nop 62fca08f32SWang Nan * b test_done 63fca08f32SWang Nan * test_after2: nop 64fca08f32SWang Nan * test_done: 65fca08f32SWang Nan * 66fca08f32SWang Nan * The test case is constructed such that test_insn branches to 67fca08f32SWang Nan * test_after2, or, if testing a conditional instruction, it may just 68fca08f32SWang Nan * continue to test_after. The probes inserted at both locations let us 69fca08f32SWang Nan * determine which happened. A similar approach is used for testing 70fca08f32SWang Nan * backwards branches... 71fca08f32SWang Nan * 72fca08f32SWang Nan * b test_before 73fca08f32SWang Nan * b test_done @ helps to cope with off by 1 branches 74fca08f32SWang Nan * test_after2: nop 75fca08f32SWang Nan * b test_done 76fca08f32SWang Nan * test_before: nop 77fca08f32SWang Nan * test_case: test_insn 78fca08f32SWang Nan * test_after: nop 79fca08f32SWang Nan * test_done: 80fca08f32SWang Nan * 81fca08f32SWang Nan * The macros used to generate the assembler instructions describe above 82fca08f32SWang Nan * are TEST_INSTRUCTION, TEST_BRANCH_F (branch forwards) and TEST_BRANCH_B 83fca08f32SWang Nan * (branch backwards). In these, the local variables numbered 1, 50, 2 and 84fca08f32SWang Nan * 99 represent: test_before, test_case, test_after2 and test_done. 85fca08f32SWang Nan * 86fca08f32SWang Nan * FRAMEWORK 87fca08f32SWang Nan * --------- 88fca08f32SWang Nan * 89fca08f32SWang Nan * Each test case is wrapped between the pair of macros TESTCASE_START and 90fca08f32SWang Nan * TESTCASE_END. As well as performing the inline assembler boilerplate, 91fca08f32SWang Nan * these call out to the kprobes_test_case_start() and 92fca08f32SWang Nan * kprobes_test_case_end() functions which drive the execution of the test 93fca08f32SWang Nan * case. The specific arguments to use for each test case are stored as 94fca08f32SWang Nan * inline data constructed using the various TEST_ARG_* macros. Putting 95fca08f32SWang Nan * this all together, a simple test case may look like: 96fca08f32SWang Nan * 97fca08f32SWang Nan * TESTCASE_START("Testing mov r0, r7") 98fca08f32SWang Nan * TEST_ARG_REG(7, 0x12345678) // Set r7=0x12345678 99fca08f32SWang Nan * TEST_ARG_END("") 100fca08f32SWang Nan * TEST_INSTRUCTION("mov r0, r7") 101fca08f32SWang Nan * TESTCASE_END 102fca08f32SWang Nan * 103fca08f32SWang Nan * Note, in practice the single convenience macro TEST_R would be used for this 104fca08f32SWang Nan * instead. 105fca08f32SWang Nan * 106fca08f32SWang Nan * The above would expand to assembler looking something like: 107fca08f32SWang Nan * 108fca08f32SWang Nan * @ TESTCASE_START 109fca08f32SWang Nan * bl __kprobes_test_case_start 110fca08f32SWang Nan * .pushsection .rodata 111fca08f32SWang Nan * "10: 112fca08f32SWang Nan * .ascii "mov r0, r7" @ text title for test case 113fca08f32SWang Nan * .byte 0 114fca08f32SWang Nan * .popsection 115fca08f32SWang Nan * @ start of inline data... 116fca08f32SWang Nan * .word 10b @ pointer to title in .rodata section 117fca08f32SWang Nan * 118fca08f32SWang Nan * @ TEST_ARG_REG 119fca08f32SWang Nan * .byte ARG_TYPE_REG 120fca08f32SWang Nan * .byte 7 121fca08f32SWang Nan * .short 0 122fca08f32SWang Nan * .word 0x1234567 123fca08f32SWang Nan * 124fca08f32SWang Nan * @ TEST_ARG_END 125fca08f32SWang Nan * .byte ARG_TYPE_END 126fca08f32SWang Nan * .byte TEST_ISA @ flags, including ISA being tested 127fca08f32SWang Nan * .short 50f-0f @ offset of 'test_before' 128fca08f32SWang Nan * .short 2f-0f @ offset of 'test_after2' (if relevent) 129fca08f32SWang Nan * .short 99f-0f @ offset of 'test_done' 130fca08f32SWang Nan * @ start of test case code... 131fca08f32SWang Nan * 0: 132fca08f32SWang Nan * .code TEST_ISA @ switch to ISA being tested 133fca08f32SWang Nan * 134fca08f32SWang Nan * @ TEST_INSTRUCTION 135fca08f32SWang Nan * 50: nop @ location for 'test_before' probe 136fca08f32SWang Nan * 1: mov r0, r7 @ the test case instruction 'test_insn' 137fca08f32SWang Nan * nop @ location for 'test_after' probe 138fca08f32SWang Nan * 139fca08f32SWang Nan * // TESTCASE_END 140fca08f32SWang Nan * 2: 141fca08f32SWang Nan * 99: bl __kprobes_test_case_end_##TEST_ISA 142fca08f32SWang Nan * .code NONMAL_ISA 143fca08f32SWang Nan * 144fca08f32SWang Nan * When the above is execute the following happens... 145fca08f32SWang Nan * 146fca08f32SWang Nan * __kprobes_test_case_start() is an assembler wrapper which sets up space 147fca08f32SWang Nan * for a stack buffer and calls the C function kprobes_test_case_start(). 148fca08f32SWang Nan * This C function will do some initial processing of the inline data and 149fca08f32SWang Nan * setup some global state. It then inserts the test_before and test_after 150fca08f32SWang Nan * kprobes and returns a value which causes the assembler wrapper to jump 151fca08f32SWang Nan * to the start of the test case code, (local label '0'). 152fca08f32SWang Nan * 153fca08f32SWang Nan * When the test case code executes, the test_before probe will be hit and 154fca08f32SWang Nan * test_before_post_handler will call setup_test_context(). This fills the 155fca08f32SWang Nan * stack buffer and CPU registers with a test pattern and then processes 156fca08f32SWang Nan * the test case arguments. In our example there is one TEST_ARG_REG which 157fca08f32SWang Nan * indicates that R7 should be loaded with the value 0x12345678. 158fca08f32SWang Nan * 159fca08f32SWang Nan * When the test_before probe ends, the test case continues and executes 160fca08f32SWang Nan * the "mov r0, r7" instruction. It then hits the test_after probe and the 161fca08f32SWang Nan * pre-handler for this (test_after_pre_handler) will save a copy of the 162fca08f32SWang Nan * CPU register context. This should now have R0 holding the same value as 163fca08f32SWang Nan * R7. 164fca08f32SWang Nan * 165fca08f32SWang Nan * Finally we get to the call to __kprobes_test_case_end_{32,16}. This is 166fca08f32SWang Nan * an assembler wrapper which switches back to the ISA used by the test 167fca08f32SWang Nan * code and calls the C function kprobes_test_case_end(). 168fca08f32SWang Nan * 169fca08f32SWang Nan * For each run through the test case, test_case_run_count is incremented 170fca08f32SWang Nan * by one. For even runs, kprobes_test_case_end() saves a copy of the 171fca08f32SWang Nan * register and stack buffer contents from the test case just run. It then 172fca08f32SWang Nan * inserts a kprobe on the test case instruction 'test_insn' and returns a 173fca08f32SWang Nan * value to cause the test case code to be re-run. 174fca08f32SWang Nan * 175fca08f32SWang Nan * For odd numbered runs, kprobes_test_case_end() compares the register and 176fca08f32SWang Nan * stack buffer contents to those that were saved on the previous even 177fca08f32SWang Nan * numbered run (the one without the kprobe on test_insn). These should be 178fca08f32SWang Nan * the same if the kprobe instruction simulation routine is correct. 179fca08f32SWang Nan * 180fca08f32SWang Nan * The pair of test case runs is repeated with different combinations of 181fca08f32SWang Nan * flag values in CPSR and, for Thumb, different ITState. This is 182fca08f32SWang Nan * controlled by test_context_cpsr(). 183fca08f32SWang Nan * 184fca08f32SWang Nan * BUILDING TEST CASES 185fca08f32SWang Nan * ------------------- 186fca08f32SWang Nan * 187fca08f32SWang Nan * 188fca08f32SWang Nan * As an aid to building test cases, the stack buffer is initialised with 189fca08f32SWang Nan * some special values: 190fca08f32SWang Nan * 191fca08f32SWang Nan * [SP+13*4] Contains SP+120. This can be used to test instructions 192fca08f32SWang Nan * which load a value into SP. 193fca08f32SWang Nan * 194fca08f32SWang Nan * [SP+15*4] When testing branching instructions using TEST_BRANCH_{F,B}, 195fca08f32SWang Nan * this holds the target address of the branch, 'test_after2'. 196fca08f32SWang Nan * This can be used to test instructions which load a PC value 197fca08f32SWang Nan * from memory. 198fca08f32SWang Nan */ 199fca08f32SWang Nan 200fca08f32SWang Nan #include <linux/kernel.h> 201fca08f32SWang Nan #include <linux/module.h> 202fca08f32SWang Nan #include <linux/slab.h> 203e6017571SIngo Molnar #include <linux/sched/clock.h> 204fca08f32SWang Nan #include <linux/kprobes.h> 205fca08f32SWang Nan #include <linux/errno.h> 206fca08f32SWang Nan #include <linux/stddef.h> 207fca08f32SWang Nan #include <linux/bug.h> 208fca08f32SWang Nan #include <asm/opcodes.h> 209fca08f32SWang Nan 210fca08f32SWang Nan #include "core.h" 211fca08f32SWang Nan #include "test-core.h" 212fca08f32SWang Nan #include "../decode-arm.h" 213fca08f32SWang Nan #include "../decode-thumb.h" 214fca08f32SWang Nan 215fca08f32SWang Nan 216fca08f32SWang Nan #define BENCHMARKING 1 217fca08f32SWang Nan 218fca08f32SWang Nan 219fca08f32SWang Nan /* 220fca08f32SWang Nan * Test basic API 221fca08f32SWang Nan */ 222fca08f32SWang Nan 223fca08f32SWang Nan static bool test_regs_ok; 224fca08f32SWang Nan static int test_func_instance; 225fca08f32SWang Nan static int pre_handler_called; 226fca08f32SWang Nan static int post_handler_called; 227fca08f32SWang Nan static int kretprobe_handler_called; 228fca08f32SWang Nan static int tests_failed; 229fca08f32SWang Nan 230fca08f32SWang Nan #define FUNC_ARG1 0x12345678 231fca08f32SWang Nan #define FUNC_ARG2 0xabcdef 232fca08f32SWang Nan 233fca08f32SWang Nan 234fca08f32SWang Nan #ifndef CONFIG_THUMB2_KERNEL 235fca08f32SWang Nan 236fb892bd0SJon Medhurst #define RET(reg) "mov pc, "#reg 237fb892bd0SJon Medhurst 238fca08f32SWang Nan long arm_func(long r0, long r1); 239fca08f32SWang Nan 240fca08f32SWang Nan static void __used __naked __arm_kprobes_test_func(void) 241fca08f32SWang Nan { 242fca08f32SWang Nan __asm__ __volatile__ ( 243fca08f32SWang Nan ".arm \n\t" 244fca08f32SWang Nan ".type arm_func, %%function \n\t" 245fca08f32SWang Nan "arm_func: \n\t" 246fca08f32SWang Nan "adds r0, r0, r1 \n\t" 247fb892bd0SJon Medhurst "mov pc, lr \n\t" 248fca08f32SWang Nan ".code "NORMAL_ISA /* Back to Thumb if necessary */ 249fca08f32SWang Nan : : : "r0", "r1", "cc" 250fca08f32SWang Nan ); 251fca08f32SWang Nan } 252fca08f32SWang Nan 253fca08f32SWang Nan #else /* CONFIG_THUMB2_KERNEL */ 254fca08f32SWang Nan 255fb892bd0SJon Medhurst #define RET(reg) "bx "#reg 256fb892bd0SJon Medhurst 257fca08f32SWang Nan long thumb16_func(long r0, long r1); 258fca08f32SWang Nan long thumb32even_func(long r0, long r1); 259fca08f32SWang Nan long thumb32odd_func(long r0, long r1); 260fca08f32SWang Nan 261fca08f32SWang Nan static void __used __naked __thumb_kprobes_test_funcs(void) 262fca08f32SWang Nan { 263fca08f32SWang Nan __asm__ __volatile__ ( 264fca08f32SWang Nan ".type thumb16_func, %%function \n\t" 265fca08f32SWang Nan "thumb16_func: \n\t" 266fca08f32SWang Nan "adds.n r0, r0, r1 \n\t" 267fca08f32SWang Nan "bx lr \n\t" 268fca08f32SWang Nan 269fca08f32SWang Nan ".align \n\t" 270fca08f32SWang Nan ".type thumb32even_func, %%function \n\t" 271fca08f32SWang Nan "thumb32even_func: \n\t" 272fca08f32SWang Nan "adds.w r0, r0, r1 \n\t" 273fca08f32SWang Nan "bx lr \n\t" 274fca08f32SWang Nan 275fca08f32SWang Nan ".align \n\t" 276fca08f32SWang Nan "nop.n \n\t" 277fca08f32SWang Nan ".type thumb32odd_func, %%function \n\t" 278fca08f32SWang Nan "thumb32odd_func: \n\t" 279fca08f32SWang Nan "adds.w r0, r0, r1 \n\t" 280fca08f32SWang Nan "bx lr \n\t" 281fca08f32SWang Nan 282fca08f32SWang Nan : : : "r0", "r1", "cc" 283fca08f32SWang Nan ); 284fca08f32SWang Nan } 285fca08f32SWang Nan 286fca08f32SWang Nan #endif /* CONFIG_THUMB2_KERNEL */ 287fca08f32SWang Nan 288fca08f32SWang Nan 289fca08f32SWang Nan static int call_test_func(long (*func)(long, long), bool check_test_regs) 290fca08f32SWang Nan { 291fca08f32SWang Nan long ret; 292fca08f32SWang Nan 293fca08f32SWang Nan ++test_func_instance; 294fca08f32SWang Nan test_regs_ok = false; 295fca08f32SWang Nan 296fca08f32SWang Nan ret = (*func)(FUNC_ARG1, FUNC_ARG2); 297fca08f32SWang Nan if (ret != FUNC_ARG1 + FUNC_ARG2) { 298fca08f32SWang Nan pr_err("FAIL: call_test_func: func returned %lx\n", ret); 299fca08f32SWang Nan return false; 300fca08f32SWang Nan } 301fca08f32SWang Nan 302fca08f32SWang Nan if (check_test_regs && !test_regs_ok) { 303fca08f32SWang Nan pr_err("FAIL: test regs not OK\n"); 304fca08f32SWang Nan return false; 305fca08f32SWang Nan } 306fca08f32SWang Nan 307fca08f32SWang Nan return true; 308fca08f32SWang Nan } 309fca08f32SWang Nan 310fca08f32SWang Nan static int __kprobes pre_handler(struct kprobe *p, struct pt_regs *regs) 311fca08f32SWang Nan { 312fca08f32SWang Nan pre_handler_called = test_func_instance; 313fca08f32SWang Nan if (regs->ARM_r0 == FUNC_ARG1 && regs->ARM_r1 == FUNC_ARG2) 314fca08f32SWang Nan test_regs_ok = true; 315fca08f32SWang Nan return 0; 316fca08f32SWang Nan } 317fca08f32SWang Nan 318fca08f32SWang Nan static void __kprobes post_handler(struct kprobe *p, struct pt_regs *regs, 319fca08f32SWang Nan unsigned long flags) 320fca08f32SWang Nan { 321fca08f32SWang Nan post_handler_called = test_func_instance; 322fca08f32SWang Nan if (regs->ARM_r0 != FUNC_ARG1 + FUNC_ARG2 || regs->ARM_r1 != FUNC_ARG2) 323fca08f32SWang Nan test_regs_ok = false; 324fca08f32SWang Nan } 325fca08f32SWang Nan 326fca08f32SWang Nan static struct kprobe the_kprobe = { 327fca08f32SWang Nan .addr = 0, 328fca08f32SWang Nan .pre_handler = pre_handler, 329fca08f32SWang Nan .post_handler = post_handler 330fca08f32SWang Nan }; 331fca08f32SWang Nan 332fca08f32SWang Nan static int test_kprobe(long (*func)(long, long)) 333fca08f32SWang Nan { 334fca08f32SWang Nan int ret; 335fca08f32SWang Nan 336fca08f32SWang Nan the_kprobe.addr = (kprobe_opcode_t *)func; 337fca08f32SWang Nan ret = register_kprobe(&the_kprobe); 338fca08f32SWang Nan if (ret < 0) { 339fca08f32SWang Nan pr_err("FAIL: register_kprobe failed with %d\n", ret); 340fca08f32SWang Nan return ret; 341fca08f32SWang Nan } 342fca08f32SWang Nan 343fca08f32SWang Nan ret = call_test_func(func, true); 344fca08f32SWang Nan 345fca08f32SWang Nan unregister_kprobe(&the_kprobe); 346fca08f32SWang Nan the_kprobe.flags = 0; /* Clear disable flag to allow reuse */ 347fca08f32SWang Nan 348fca08f32SWang Nan if (!ret) 349fca08f32SWang Nan return -EINVAL; 350fca08f32SWang Nan if (pre_handler_called != test_func_instance) { 351fca08f32SWang Nan pr_err("FAIL: kprobe pre_handler not called\n"); 352fca08f32SWang Nan return -EINVAL; 353fca08f32SWang Nan } 354fca08f32SWang Nan if (post_handler_called != test_func_instance) { 355fca08f32SWang Nan pr_err("FAIL: kprobe post_handler not called\n"); 356fca08f32SWang Nan return -EINVAL; 357fca08f32SWang Nan } 358fca08f32SWang Nan if (!call_test_func(func, false)) 359fca08f32SWang Nan return -EINVAL; 360fca08f32SWang Nan if (pre_handler_called == test_func_instance || 361fca08f32SWang Nan post_handler_called == test_func_instance) { 362fca08f32SWang Nan pr_err("FAIL: probe called after unregistering\n"); 363fca08f32SWang Nan return -EINVAL; 364fca08f32SWang Nan } 365fca08f32SWang Nan 366fca08f32SWang Nan return 0; 367fca08f32SWang Nan } 368fca08f32SWang Nan 369fca08f32SWang Nan static int __kprobes 370fca08f32SWang Nan kretprobe_handler(struct kretprobe_instance *ri, struct pt_regs *regs) 371fca08f32SWang Nan { 372fca08f32SWang Nan kretprobe_handler_called = test_func_instance; 373fca08f32SWang Nan if (regs_return_value(regs) == FUNC_ARG1 + FUNC_ARG2) 374fca08f32SWang Nan test_regs_ok = true; 375fca08f32SWang Nan return 0; 376fca08f32SWang Nan } 377fca08f32SWang Nan 378fca08f32SWang Nan static struct kretprobe the_kretprobe = { 379fca08f32SWang Nan .handler = kretprobe_handler, 380fca08f32SWang Nan }; 381fca08f32SWang Nan 382fca08f32SWang Nan static int test_kretprobe(long (*func)(long, long)) 383fca08f32SWang Nan { 384fca08f32SWang Nan int ret; 385fca08f32SWang Nan 386fca08f32SWang Nan the_kretprobe.kp.addr = (kprobe_opcode_t *)func; 387fca08f32SWang Nan ret = register_kretprobe(&the_kretprobe); 388fca08f32SWang Nan if (ret < 0) { 389fca08f32SWang Nan pr_err("FAIL: register_kretprobe failed with %d\n", ret); 390fca08f32SWang Nan return ret; 391fca08f32SWang Nan } 392fca08f32SWang Nan 393fca08f32SWang Nan ret = call_test_func(func, true); 394fca08f32SWang Nan 395fca08f32SWang Nan unregister_kretprobe(&the_kretprobe); 396fca08f32SWang Nan the_kretprobe.kp.flags = 0; /* Clear disable flag to allow reuse */ 397fca08f32SWang Nan 398fca08f32SWang Nan if (!ret) 399fca08f32SWang Nan return -EINVAL; 400fca08f32SWang Nan if (kretprobe_handler_called != test_func_instance) { 401fca08f32SWang Nan pr_err("FAIL: kretprobe handler not called\n"); 402fca08f32SWang Nan return -EINVAL; 403fca08f32SWang Nan } 404fca08f32SWang Nan if (!call_test_func(func, false)) 405fca08f32SWang Nan return -EINVAL; 4064650209bSMasami Hiramatsu if (kretprobe_handler_called == test_func_instance) { 407fca08f32SWang Nan pr_err("FAIL: kretprobe called after unregistering\n"); 408fca08f32SWang Nan return -EINVAL; 409fca08f32SWang Nan } 410fca08f32SWang Nan 411fca08f32SWang Nan return 0; 412fca08f32SWang Nan } 413fca08f32SWang Nan 414fca08f32SWang Nan static int run_api_tests(long (*func)(long, long)) 415fca08f32SWang Nan { 416fca08f32SWang Nan int ret; 417fca08f32SWang Nan 418fca08f32SWang Nan pr_info(" kprobe\n"); 419fca08f32SWang Nan ret = test_kprobe(func); 420fca08f32SWang Nan if (ret < 0) 421fca08f32SWang Nan return ret; 422fca08f32SWang Nan 423fca08f32SWang Nan pr_info(" kretprobe\n"); 424fca08f32SWang Nan ret = test_kretprobe(func); 425fca08f32SWang Nan if (ret < 0) 426fca08f32SWang Nan return ret; 427fca08f32SWang Nan 428fca08f32SWang Nan return 0; 429fca08f32SWang Nan } 430fca08f32SWang Nan 431fca08f32SWang Nan 432fca08f32SWang Nan /* 433fca08f32SWang Nan * Benchmarking 434fca08f32SWang Nan */ 435fca08f32SWang Nan 436fca08f32SWang Nan #if BENCHMARKING 437fca08f32SWang Nan 438fca08f32SWang Nan static void __naked benchmark_nop(void) 439fca08f32SWang Nan { 440fca08f32SWang Nan __asm__ __volatile__ ( 441fca08f32SWang Nan "nop \n\t" 442fb892bd0SJon Medhurst RET(lr)" \n\t" 443fca08f32SWang Nan ); 444fca08f32SWang Nan } 445fca08f32SWang Nan 446fca08f32SWang Nan #ifdef CONFIG_THUMB2_KERNEL 447fca08f32SWang Nan #define wide ".w" 448fca08f32SWang Nan #else 449fca08f32SWang Nan #define wide 450fca08f32SWang Nan #endif 451fca08f32SWang Nan 452fca08f32SWang Nan static void __naked benchmark_pushpop1(void) 453fca08f32SWang Nan { 454fca08f32SWang Nan __asm__ __volatile__ ( 455fca08f32SWang Nan "stmdb"wide" sp!, {r3-r11,lr} \n\t" 456fca08f32SWang Nan "ldmia"wide" sp!, {r3-r11,pc}" 457fca08f32SWang Nan ); 458fca08f32SWang Nan } 459fca08f32SWang Nan 460fca08f32SWang Nan static void __naked benchmark_pushpop2(void) 461fca08f32SWang Nan { 462fca08f32SWang Nan __asm__ __volatile__ ( 463fca08f32SWang Nan "stmdb"wide" sp!, {r0-r8,lr} \n\t" 464fca08f32SWang Nan "ldmia"wide" sp!, {r0-r8,pc}" 465fca08f32SWang Nan ); 466fca08f32SWang Nan } 467fca08f32SWang Nan 468fca08f32SWang Nan static void __naked benchmark_pushpop3(void) 469fca08f32SWang Nan { 470fca08f32SWang Nan __asm__ __volatile__ ( 471fca08f32SWang Nan "stmdb"wide" sp!, {r4,lr} \n\t" 472fca08f32SWang Nan "ldmia"wide" sp!, {r4,pc}" 473fca08f32SWang Nan ); 474fca08f32SWang Nan } 475fca08f32SWang Nan 476fca08f32SWang Nan static void __naked benchmark_pushpop4(void) 477fca08f32SWang Nan { 478fca08f32SWang Nan __asm__ __volatile__ ( 479fca08f32SWang Nan "stmdb"wide" sp!, {r0,lr} \n\t" 480fca08f32SWang Nan "ldmia"wide" sp!, {r0,pc}" 481fca08f32SWang Nan ); 482fca08f32SWang Nan } 483fca08f32SWang Nan 484fca08f32SWang Nan 485fca08f32SWang Nan #ifdef CONFIG_THUMB2_KERNEL 486fca08f32SWang Nan 487fca08f32SWang Nan static void __naked benchmark_pushpop_thumb(void) 488fca08f32SWang Nan { 489fca08f32SWang Nan __asm__ __volatile__ ( 490fca08f32SWang Nan "push.n {r0-r7,lr} \n\t" 491fca08f32SWang Nan "pop.n {r0-r7,pc}" 492fca08f32SWang Nan ); 493fca08f32SWang Nan } 494fca08f32SWang Nan 495fca08f32SWang Nan #endif 496fca08f32SWang Nan 497fca08f32SWang Nan static int __kprobes 498fca08f32SWang Nan benchmark_pre_handler(struct kprobe *p, struct pt_regs *regs) 499fca08f32SWang Nan { 500fca08f32SWang Nan return 0; 501fca08f32SWang Nan } 502fca08f32SWang Nan 503fca08f32SWang Nan static int benchmark(void(*fn)(void)) 504fca08f32SWang Nan { 505fca08f32SWang Nan unsigned n, i, t, t0; 506fca08f32SWang Nan 507fca08f32SWang Nan for (n = 1000; ; n *= 2) { 508fca08f32SWang Nan t0 = sched_clock(); 509fca08f32SWang Nan for (i = n; i > 0; --i) 510fca08f32SWang Nan fn(); 511fca08f32SWang Nan t = sched_clock() - t0; 512fca08f32SWang Nan if (t >= 250000000) 513fca08f32SWang Nan break; /* Stop once we took more than 0.25 seconds */ 514fca08f32SWang Nan } 515fca08f32SWang Nan return t / n; /* Time for one iteration in nanoseconds */ 516fca08f32SWang Nan }; 517fca08f32SWang Nan 518fca08f32SWang Nan static int kprobe_benchmark(void(*fn)(void), unsigned offset) 519fca08f32SWang Nan { 520fca08f32SWang Nan struct kprobe k = { 521fca08f32SWang Nan .addr = (kprobe_opcode_t *)((uintptr_t)fn + offset), 522fca08f32SWang Nan .pre_handler = benchmark_pre_handler, 523fca08f32SWang Nan }; 524fca08f32SWang Nan 525fca08f32SWang Nan int ret = register_kprobe(&k); 526fca08f32SWang Nan if (ret < 0) { 527fca08f32SWang Nan pr_err("FAIL: register_kprobe failed with %d\n", ret); 528fca08f32SWang Nan return ret; 529fca08f32SWang Nan } 530fca08f32SWang Nan 531fca08f32SWang Nan ret = benchmark(fn); 532fca08f32SWang Nan 533fca08f32SWang Nan unregister_kprobe(&k); 534fca08f32SWang Nan return ret; 535fca08f32SWang Nan }; 536fca08f32SWang Nan 537fca08f32SWang Nan struct benchmarks { 538fca08f32SWang Nan void (*fn)(void); 539fca08f32SWang Nan unsigned offset; 540fca08f32SWang Nan const char *title; 541fca08f32SWang Nan }; 542fca08f32SWang Nan 543fca08f32SWang Nan static int run_benchmarks(void) 544fca08f32SWang Nan { 545fca08f32SWang Nan int ret; 546fca08f32SWang Nan struct benchmarks list[] = { 547fca08f32SWang Nan {&benchmark_nop, 0, "nop"}, 548fca08f32SWang Nan /* 549fca08f32SWang Nan * benchmark_pushpop{1,3} will have the optimised 550fca08f32SWang Nan * instruction emulation, whilst benchmark_pushpop{2,4} will 551fca08f32SWang Nan * be the equivalent unoptimised instructions. 552fca08f32SWang Nan */ 553fca08f32SWang Nan {&benchmark_pushpop1, 0, "stmdb sp!, {r3-r11,lr}"}, 554fca08f32SWang Nan {&benchmark_pushpop1, 4, "ldmia sp!, {r3-r11,pc}"}, 555fca08f32SWang Nan {&benchmark_pushpop2, 0, "stmdb sp!, {r0-r8,lr}"}, 556fca08f32SWang Nan {&benchmark_pushpop2, 4, "ldmia sp!, {r0-r8,pc}"}, 557fca08f32SWang Nan {&benchmark_pushpop3, 0, "stmdb sp!, {r4,lr}"}, 558fca08f32SWang Nan {&benchmark_pushpop3, 4, "ldmia sp!, {r4,pc}"}, 559fca08f32SWang Nan {&benchmark_pushpop4, 0, "stmdb sp!, {r0,lr}"}, 560fca08f32SWang Nan {&benchmark_pushpop4, 4, "ldmia sp!, {r0,pc}"}, 561fca08f32SWang Nan #ifdef CONFIG_THUMB2_KERNEL 562fca08f32SWang Nan {&benchmark_pushpop_thumb, 0, "push.n {r0-r7,lr}"}, 563fca08f32SWang Nan {&benchmark_pushpop_thumb, 2, "pop.n {r0-r7,pc}"}, 564fca08f32SWang Nan #endif 565fca08f32SWang Nan {0} 566fca08f32SWang Nan }; 567fca08f32SWang Nan 568fca08f32SWang Nan struct benchmarks *b; 569fca08f32SWang Nan for (b = list; b->fn; ++b) { 570fca08f32SWang Nan ret = kprobe_benchmark(b->fn, b->offset); 571fca08f32SWang Nan if (ret < 0) 572fca08f32SWang Nan return ret; 573fca08f32SWang Nan pr_info(" %dns for kprobe %s\n", ret, b->title); 574fca08f32SWang Nan } 575fca08f32SWang Nan 576fca08f32SWang Nan pr_info("\n"); 577fca08f32SWang Nan return 0; 578fca08f32SWang Nan } 579fca08f32SWang Nan 580fca08f32SWang Nan #endif /* BENCHMARKING */ 581fca08f32SWang Nan 582fca08f32SWang Nan 583fca08f32SWang Nan /* 584fca08f32SWang Nan * Decoding table self-consistency tests 585fca08f32SWang Nan */ 586fca08f32SWang Nan 587fca08f32SWang Nan static const int decode_struct_sizes[NUM_DECODE_TYPES] = { 588fca08f32SWang Nan [DECODE_TYPE_TABLE] = sizeof(struct decode_table), 589fca08f32SWang Nan [DECODE_TYPE_CUSTOM] = sizeof(struct decode_custom), 590fca08f32SWang Nan [DECODE_TYPE_SIMULATE] = sizeof(struct decode_simulate), 591fca08f32SWang Nan [DECODE_TYPE_EMULATE] = sizeof(struct decode_emulate), 592fca08f32SWang Nan [DECODE_TYPE_OR] = sizeof(struct decode_or), 593fca08f32SWang Nan [DECODE_TYPE_REJECT] = sizeof(struct decode_reject) 594fca08f32SWang Nan }; 595fca08f32SWang Nan 596fca08f32SWang Nan static int table_iter(const union decode_item *table, 597fca08f32SWang Nan int (*fn)(const struct decode_header *, void *), 598fca08f32SWang Nan void *args) 599fca08f32SWang Nan { 600fca08f32SWang Nan const struct decode_header *h = (struct decode_header *)table; 601fca08f32SWang Nan int result; 602fca08f32SWang Nan 603fca08f32SWang Nan for (;;) { 604fca08f32SWang Nan enum decode_type type = h->type_regs.bits & DECODE_TYPE_MASK; 605fca08f32SWang Nan 606fca08f32SWang Nan if (type == DECODE_TYPE_END) 607fca08f32SWang Nan return 0; 608fca08f32SWang Nan 609fca08f32SWang Nan result = fn(h, args); 610fca08f32SWang Nan if (result) 611fca08f32SWang Nan return result; 612fca08f32SWang Nan 613fca08f32SWang Nan h = (struct decode_header *) 614fca08f32SWang Nan ((uintptr_t)h + decode_struct_sizes[type]); 615fca08f32SWang Nan 616fca08f32SWang Nan } 617fca08f32SWang Nan } 618fca08f32SWang Nan 619fca08f32SWang Nan static int table_test_fail(const struct decode_header *h, const char* message) 620fca08f32SWang Nan { 621fca08f32SWang Nan 622fca08f32SWang Nan pr_err("FAIL: kprobes test failure \"%s\" (mask %08x, value %08x)\n", 623fca08f32SWang Nan message, h->mask.bits, h->value.bits); 624fca08f32SWang Nan return -EINVAL; 625fca08f32SWang Nan } 626fca08f32SWang Nan 627fca08f32SWang Nan struct table_test_args { 628fca08f32SWang Nan const union decode_item *root_table; 629fca08f32SWang Nan u32 parent_mask; 630fca08f32SWang Nan u32 parent_value; 631fca08f32SWang Nan }; 632fca08f32SWang Nan 633fca08f32SWang Nan static int table_test_fn(const struct decode_header *h, void *args) 634fca08f32SWang Nan { 635fca08f32SWang Nan struct table_test_args *a = (struct table_test_args *)args; 636fca08f32SWang Nan enum decode_type type = h->type_regs.bits & DECODE_TYPE_MASK; 637fca08f32SWang Nan 638fca08f32SWang Nan if (h->value.bits & ~h->mask.bits) 639fca08f32SWang Nan return table_test_fail(h, "Match value has bits not in mask"); 640fca08f32SWang Nan 641fca08f32SWang Nan if ((h->mask.bits & a->parent_mask) != a->parent_mask) 642fca08f32SWang Nan return table_test_fail(h, "Mask has bits not in parent mask"); 643fca08f32SWang Nan 644fca08f32SWang Nan if ((h->value.bits ^ a->parent_value) & a->parent_mask) 645fca08f32SWang Nan return table_test_fail(h, "Value is inconsistent with parent"); 646fca08f32SWang Nan 647fca08f32SWang Nan if (type == DECODE_TYPE_TABLE) { 648fca08f32SWang Nan struct decode_table *d = (struct decode_table *)h; 649fca08f32SWang Nan struct table_test_args args2 = *a; 650fca08f32SWang Nan args2.parent_mask = h->mask.bits; 651fca08f32SWang Nan args2.parent_value = h->value.bits; 652fca08f32SWang Nan return table_iter(d->table.table, table_test_fn, &args2); 653fca08f32SWang Nan } 654fca08f32SWang Nan 655fca08f32SWang Nan return 0; 656fca08f32SWang Nan } 657fca08f32SWang Nan 658fca08f32SWang Nan static int table_test(const union decode_item *table) 659fca08f32SWang Nan { 660fca08f32SWang Nan struct table_test_args args = { 661fca08f32SWang Nan .root_table = table, 662fca08f32SWang Nan .parent_mask = 0, 663fca08f32SWang Nan .parent_value = 0 664fca08f32SWang Nan }; 665fca08f32SWang Nan return table_iter(args.root_table, table_test_fn, &args); 666fca08f32SWang Nan } 667fca08f32SWang Nan 668fca08f32SWang Nan 669fca08f32SWang Nan /* 670fca08f32SWang Nan * Decoding table test coverage analysis 671fca08f32SWang Nan * 672fca08f32SWang Nan * coverage_start() builds a coverage_table which contains a list of 673fca08f32SWang Nan * coverage_entry's to match each entry in the specified kprobes instruction 674fca08f32SWang Nan * decoding table. 675fca08f32SWang Nan * 676fca08f32SWang Nan * When test cases are run, coverage_add() is called to process each case. 677fca08f32SWang Nan * This looks up the corresponding entry in the coverage_table and sets it as 678fca08f32SWang Nan * being matched, as well as clearing the regs flag appropriate for the test. 679fca08f32SWang Nan * 680fca08f32SWang Nan * After all test cases have been run, coverage_end() is called to check that 681fca08f32SWang Nan * all entries in coverage_table have been matched and that all regs flags are 682fca08f32SWang Nan * cleared. I.e. that all possible combinations of instructions described by 683fca08f32SWang Nan * the kprobes decoding tables have had a test case executed for them. 684fca08f32SWang Nan */ 685fca08f32SWang Nan 686fca08f32SWang Nan bool coverage_fail; 687fca08f32SWang Nan 688fca08f32SWang Nan #define MAX_COVERAGE_ENTRIES 256 689fca08f32SWang Nan 690fca08f32SWang Nan struct coverage_entry { 691fca08f32SWang Nan const struct decode_header *header; 692fca08f32SWang Nan unsigned regs; 693fca08f32SWang Nan unsigned nesting; 694fca08f32SWang Nan char matched; 695fca08f32SWang Nan }; 696fca08f32SWang Nan 697fca08f32SWang Nan struct coverage_table { 698fca08f32SWang Nan struct coverage_entry *base; 699fca08f32SWang Nan unsigned num_entries; 700fca08f32SWang Nan unsigned nesting; 701fca08f32SWang Nan }; 702fca08f32SWang Nan 703fca08f32SWang Nan struct coverage_table coverage; 704fca08f32SWang Nan 705fca08f32SWang Nan #define COVERAGE_ANY_REG (1<<0) 706fca08f32SWang Nan #define COVERAGE_SP (1<<1) 707fca08f32SWang Nan #define COVERAGE_PC (1<<2) 708fca08f32SWang Nan #define COVERAGE_PCWB (1<<3) 709fca08f32SWang Nan 710fca08f32SWang Nan static const char coverage_register_lookup[16] = { 711fca08f32SWang Nan [REG_TYPE_ANY] = COVERAGE_ANY_REG | COVERAGE_SP | COVERAGE_PC, 712fca08f32SWang Nan [REG_TYPE_SAMEAS16] = COVERAGE_ANY_REG, 713fca08f32SWang Nan [REG_TYPE_SP] = COVERAGE_SP, 714fca08f32SWang Nan [REG_TYPE_PC] = COVERAGE_PC, 715fca08f32SWang Nan [REG_TYPE_NOSP] = COVERAGE_ANY_REG | COVERAGE_SP, 716fca08f32SWang Nan [REG_TYPE_NOSPPC] = COVERAGE_ANY_REG | COVERAGE_SP | COVERAGE_PC, 717fca08f32SWang Nan [REG_TYPE_NOPC] = COVERAGE_ANY_REG | COVERAGE_PC, 718fca08f32SWang Nan [REG_TYPE_NOPCWB] = COVERAGE_ANY_REG | COVERAGE_PC | COVERAGE_PCWB, 719fca08f32SWang Nan [REG_TYPE_NOPCX] = COVERAGE_ANY_REG, 720fca08f32SWang Nan [REG_TYPE_NOSPPCX] = COVERAGE_ANY_REG | COVERAGE_SP, 721fca08f32SWang Nan }; 722fca08f32SWang Nan 723fca08f32SWang Nan unsigned coverage_start_registers(const struct decode_header *h) 724fca08f32SWang Nan { 725fca08f32SWang Nan unsigned regs = 0; 726fca08f32SWang Nan int i; 727fca08f32SWang Nan for (i = 0; i < 20; i += 4) { 728fca08f32SWang Nan int r = (h->type_regs.bits >> (DECODE_TYPE_BITS + i)) & 0xf; 729fca08f32SWang Nan regs |= coverage_register_lookup[r] << i; 730fca08f32SWang Nan } 731fca08f32SWang Nan return regs; 732fca08f32SWang Nan } 733fca08f32SWang Nan 734fca08f32SWang Nan static int coverage_start_fn(const struct decode_header *h, void *args) 735fca08f32SWang Nan { 736fca08f32SWang Nan struct coverage_table *coverage = (struct coverage_table *)args; 737fca08f32SWang Nan enum decode_type type = h->type_regs.bits & DECODE_TYPE_MASK; 738fca08f32SWang Nan struct coverage_entry *entry = coverage->base + coverage->num_entries; 739fca08f32SWang Nan 740fca08f32SWang Nan if (coverage->num_entries == MAX_COVERAGE_ENTRIES - 1) { 741fca08f32SWang Nan pr_err("FAIL: Out of space for test coverage data"); 742fca08f32SWang Nan return -ENOMEM; 743fca08f32SWang Nan } 744fca08f32SWang Nan 745fca08f32SWang Nan ++coverage->num_entries; 746fca08f32SWang Nan 747fca08f32SWang Nan entry->header = h; 748fca08f32SWang Nan entry->regs = coverage_start_registers(h); 749fca08f32SWang Nan entry->nesting = coverage->nesting; 750fca08f32SWang Nan entry->matched = false; 751fca08f32SWang Nan 752fca08f32SWang Nan if (type == DECODE_TYPE_TABLE) { 753fca08f32SWang Nan struct decode_table *d = (struct decode_table *)h; 754fca08f32SWang Nan int ret; 755fca08f32SWang Nan ++coverage->nesting; 756fca08f32SWang Nan ret = table_iter(d->table.table, coverage_start_fn, coverage); 757fca08f32SWang Nan --coverage->nesting; 758fca08f32SWang Nan return ret; 759fca08f32SWang Nan } 760fca08f32SWang Nan 761fca08f32SWang Nan return 0; 762fca08f32SWang Nan } 763fca08f32SWang Nan 764fca08f32SWang Nan static int coverage_start(const union decode_item *table) 765fca08f32SWang Nan { 7666da2ec56SKees Cook coverage.base = kmalloc_array(MAX_COVERAGE_ENTRIES, 7676da2ec56SKees Cook sizeof(struct coverage_entry), 7686da2ec56SKees Cook GFP_KERNEL); 769fca08f32SWang Nan coverage.num_entries = 0; 770fca08f32SWang Nan coverage.nesting = 0; 771fca08f32SWang Nan return table_iter(table, coverage_start_fn, &coverage); 772fca08f32SWang Nan } 773fca08f32SWang Nan 774fca08f32SWang Nan static void 775fca08f32SWang Nan coverage_add_registers(struct coverage_entry *entry, kprobe_opcode_t insn) 776fca08f32SWang Nan { 777fca08f32SWang Nan int regs = entry->header->type_regs.bits >> DECODE_TYPE_BITS; 778fca08f32SWang Nan int i; 779fca08f32SWang Nan for (i = 0; i < 20; i += 4) { 780fca08f32SWang Nan enum decode_reg_type reg_type = (regs >> i) & 0xf; 781fca08f32SWang Nan int reg = (insn >> i) & 0xf; 782fca08f32SWang Nan int flag; 783fca08f32SWang Nan 784fca08f32SWang Nan if (!reg_type) 785fca08f32SWang Nan continue; 786fca08f32SWang Nan 787fca08f32SWang Nan if (reg == 13) 788fca08f32SWang Nan flag = COVERAGE_SP; 789fca08f32SWang Nan else if (reg == 15) 790fca08f32SWang Nan flag = COVERAGE_PC; 791fca08f32SWang Nan else 792fca08f32SWang Nan flag = COVERAGE_ANY_REG; 793fca08f32SWang Nan entry->regs &= ~(flag << i); 794fca08f32SWang Nan 795fca08f32SWang Nan switch (reg_type) { 796fca08f32SWang Nan 797fca08f32SWang Nan case REG_TYPE_NONE: 798fca08f32SWang Nan case REG_TYPE_ANY: 799fca08f32SWang Nan case REG_TYPE_SAMEAS16: 800fca08f32SWang Nan break; 801fca08f32SWang Nan 802fca08f32SWang Nan case REG_TYPE_SP: 803fca08f32SWang Nan if (reg != 13) 804fca08f32SWang Nan return; 805fca08f32SWang Nan break; 806fca08f32SWang Nan 807fca08f32SWang Nan case REG_TYPE_PC: 808fca08f32SWang Nan if (reg != 15) 809fca08f32SWang Nan return; 810fca08f32SWang Nan break; 811fca08f32SWang Nan 812fca08f32SWang Nan case REG_TYPE_NOSP: 813fca08f32SWang Nan if (reg == 13) 814fca08f32SWang Nan return; 815fca08f32SWang Nan break; 816fca08f32SWang Nan 817fca08f32SWang Nan case REG_TYPE_NOSPPC: 818fca08f32SWang Nan case REG_TYPE_NOSPPCX: 819fca08f32SWang Nan if (reg == 13 || reg == 15) 820fca08f32SWang Nan return; 821fca08f32SWang Nan break; 822fca08f32SWang Nan 823fca08f32SWang Nan case REG_TYPE_NOPCWB: 824fca08f32SWang Nan if (!is_writeback(insn)) 825fca08f32SWang Nan break; 826fca08f32SWang Nan if (reg == 15) { 827fca08f32SWang Nan entry->regs &= ~(COVERAGE_PCWB << i); 828fca08f32SWang Nan return; 829fca08f32SWang Nan } 830fca08f32SWang Nan break; 831fca08f32SWang Nan 832fca08f32SWang Nan case REG_TYPE_NOPC: 833fca08f32SWang Nan case REG_TYPE_NOPCX: 834fca08f32SWang Nan if (reg == 15) 835fca08f32SWang Nan return; 836fca08f32SWang Nan break; 837fca08f32SWang Nan } 838fca08f32SWang Nan 839fca08f32SWang Nan } 840fca08f32SWang Nan } 841fca08f32SWang Nan 842fca08f32SWang Nan static void coverage_add(kprobe_opcode_t insn) 843fca08f32SWang Nan { 844fca08f32SWang Nan struct coverage_entry *entry = coverage.base; 845fca08f32SWang Nan struct coverage_entry *end = coverage.base + coverage.num_entries; 846fca08f32SWang Nan bool matched = false; 847fca08f32SWang Nan unsigned nesting = 0; 848fca08f32SWang Nan 849fca08f32SWang Nan for (; entry < end; ++entry) { 850fca08f32SWang Nan const struct decode_header *h = entry->header; 851fca08f32SWang Nan enum decode_type type = h->type_regs.bits & DECODE_TYPE_MASK; 852fca08f32SWang Nan 853fca08f32SWang Nan if (entry->nesting > nesting) 854fca08f32SWang Nan continue; /* Skip sub-table we didn't match */ 855fca08f32SWang Nan 856fca08f32SWang Nan if (entry->nesting < nesting) 857fca08f32SWang Nan break; /* End of sub-table we were scanning */ 858fca08f32SWang Nan 859fca08f32SWang Nan if (!matched) { 860fca08f32SWang Nan if ((insn & h->mask.bits) != h->value.bits) 861fca08f32SWang Nan continue; 862fca08f32SWang Nan entry->matched = true; 863fca08f32SWang Nan } 864fca08f32SWang Nan 865fca08f32SWang Nan switch (type) { 866fca08f32SWang Nan 867fca08f32SWang Nan case DECODE_TYPE_TABLE: 868fca08f32SWang Nan ++nesting; 869fca08f32SWang Nan break; 870fca08f32SWang Nan 871fca08f32SWang Nan case DECODE_TYPE_CUSTOM: 872fca08f32SWang Nan case DECODE_TYPE_SIMULATE: 873fca08f32SWang Nan case DECODE_TYPE_EMULATE: 874fca08f32SWang Nan coverage_add_registers(entry, insn); 875fca08f32SWang Nan return; 876fca08f32SWang Nan 877fca08f32SWang Nan case DECODE_TYPE_OR: 878fca08f32SWang Nan matched = true; 879fca08f32SWang Nan break; 880fca08f32SWang Nan 881fca08f32SWang Nan case DECODE_TYPE_REJECT: 882fca08f32SWang Nan default: 883fca08f32SWang Nan return; 884fca08f32SWang Nan } 885fca08f32SWang Nan 886fca08f32SWang Nan } 887fca08f32SWang Nan } 888fca08f32SWang Nan 889fca08f32SWang Nan static void coverage_end(void) 890fca08f32SWang Nan { 891fca08f32SWang Nan struct coverage_entry *entry = coverage.base; 892fca08f32SWang Nan struct coverage_entry *end = coverage.base + coverage.num_entries; 893fca08f32SWang Nan 894fca08f32SWang Nan for (; entry < end; ++entry) { 895fca08f32SWang Nan u32 mask = entry->header->mask.bits; 896fca08f32SWang Nan u32 value = entry->header->value.bits; 897fca08f32SWang Nan 898fca08f32SWang Nan if (entry->regs) { 899fca08f32SWang Nan pr_err("FAIL: Register test coverage missing for %08x %08x (%05x)\n", 900fca08f32SWang Nan mask, value, entry->regs); 901fca08f32SWang Nan coverage_fail = true; 902fca08f32SWang Nan } 903fca08f32SWang Nan if (!entry->matched) { 904fca08f32SWang Nan pr_err("FAIL: Test coverage entry missing for %08x %08x\n", 905fca08f32SWang Nan mask, value); 906fca08f32SWang Nan coverage_fail = true; 907fca08f32SWang Nan } 908fca08f32SWang Nan } 909fca08f32SWang Nan 910fca08f32SWang Nan kfree(coverage.base); 911fca08f32SWang Nan } 912fca08f32SWang Nan 913fca08f32SWang Nan 914fca08f32SWang Nan /* 915fca08f32SWang Nan * Framework for instruction set test cases 916fca08f32SWang Nan */ 917fca08f32SWang Nan 918fca08f32SWang Nan void __naked __kprobes_test_case_start(void) 919fca08f32SWang Nan { 920fca08f32SWang Nan __asm__ __volatile__ ( 921974310d0SJon Medhurst "mov r2, sp \n\t" 922974310d0SJon Medhurst "bic r3, r2, #7 \n\t" 923974310d0SJon Medhurst "mov sp, r3 \n\t" 924974310d0SJon Medhurst "stmdb sp!, {r2-r11} \n\t" 925fca08f32SWang Nan "sub sp, sp, #"__stringify(TEST_MEMORY_SIZE)"\n\t" 926fca08f32SWang Nan "bic r0, lr, #1 @ r0 = inline data \n\t" 927fca08f32SWang Nan "mov r1, sp \n\t" 928fca08f32SWang Nan "bl kprobes_test_case_start \n\t" 929fb892bd0SJon Medhurst RET(r0)" \n\t" 930fca08f32SWang Nan ); 931fca08f32SWang Nan } 932fca08f32SWang Nan 933fca08f32SWang Nan #ifndef CONFIG_THUMB2_KERNEL 934fca08f32SWang Nan 935fca08f32SWang Nan void __naked __kprobes_test_case_end_32(void) 936fca08f32SWang Nan { 937fca08f32SWang Nan __asm__ __volatile__ ( 938fca08f32SWang Nan "mov r4, lr \n\t" 939fca08f32SWang Nan "bl kprobes_test_case_end \n\t" 940fca08f32SWang Nan "cmp r0, #0 \n\t" 941fca08f32SWang Nan "movne pc, r0 \n\t" 942fca08f32SWang Nan "mov r0, r4 \n\t" 943fca08f32SWang Nan "add sp, sp, #"__stringify(TEST_MEMORY_SIZE)"\n\t" 944974310d0SJon Medhurst "ldmia sp!, {r2-r11} \n\t" 945974310d0SJon Medhurst "mov sp, r2 \n\t" 946fca08f32SWang Nan "mov pc, r0 \n\t" 947fca08f32SWang Nan ); 948fca08f32SWang Nan } 949fca08f32SWang Nan 950fca08f32SWang Nan #else /* CONFIG_THUMB2_KERNEL */ 951fca08f32SWang Nan 952fca08f32SWang Nan void __naked __kprobes_test_case_end_16(void) 953fca08f32SWang Nan { 954fca08f32SWang Nan __asm__ __volatile__ ( 955fca08f32SWang Nan "mov r4, lr \n\t" 956fca08f32SWang Nan "bl kprobes_test_case_end \n\t" 957fca08f32SWang Nan "cmp r0, #0 \n\t" 958fca08f32SWang Nan "bxne r0 \n\t" 959fca08f32SWang Nan "mov r0, r4 \n\t" 960fca08f32SWang Nan "add sp, sp, #"__stringify(TEST_MEMORY_SIZE)"\n\t" 961974310d0SJon Medhurst "ldmia sp!, {r2-r11} \n\t" 962974310d0SJon Medhurst "mov sp, r2 \n\t" 963fca08f32SWang Nan "bx r0 \n\t" 964fca08f32SWang Nan ); 965fca08f32SWang Nan } 966fca08f32SWang Nan 967fca08f32SWang Nan void __naked __kprobes_test_case_end_32(void) 968fca08f32SWang Nan { 969fca08f32SWang Nan __asm__ __volatile__ ( 970fca08f32SWang Nan ".arm \n\t" 971fca08f32SWang Nan "orr lr, lr, #1 @ will return to Thumb code \n\t" 972fca08f32SWang Nan "ldr pc, 1f \n\t" 973fca08f32SWang Nan "1: \n\t" 974fca08f32SWang Nan ".word __kprobes_test_case_end_16 \n\t" 975fca08f32SWang Nan ); 976fca08f32SWang Nan } 977fca08f32SWang Nan 978fca08f32SWang Nan #endif 979fca08f32SWang Nan 980fca08f32SWang Nan 981fca08f32SWang Nan int kprobe_test_flags; 982fca08f32SWang Nan int kprobe_test_cc_position; 983fca08f32SWang Nan 984fca08f32SWang Nan static int test_try_count; 985fca08f32SWang Nan static int test_pass_count; 986fca08f32SWang Nan static int test_fail_count; 987fca08f32SWang Nan 988fca08f32SWang Nan static struct pt_regs initial_regs; 989fca08f32SWang Nan static struct pt_regs expected_regs; 990fca08f32SWang Nan static struct pt_regs result_regs; 991fca08f32SWang Nan 992fca08f32SWang Nan static u32 expected_memory[TEST_MEMORY_SIZE/sizeof(u32)]; 993fca08f32SWang Nan 994fca08f32SWang Nan static const char *current_title; 995fca08f32SWang Nan static struct test_arg *current_args; 996fca08f32SWang Nan static u32 *current_stack; 997fca08f32SWang Nan static uintptr_t current_branch_target; 998fca08f32SWang Nan 999fca08f32SWang Nan static uintptr_t current_code_start; 1000fca08f32SWang Nan static kprobe_opcode_t current_instruction; 1001fca08f32SWang Nan 1002fca08f32SWang Nan 1003fca08f32SWang Nan #define TEST_CASE_PASSED -1 1004fca08f32SWang Nan #define TEST_CASE_FAILED -2 1005fca08f32SWang Nan 1006fca08f32SWang Nan static int test_case_run_count; 1007fca08f32SWang Nan static bool test_case_is_thumb; 1008fca08f32SWang Nan static int test_instance; 1009fca08f32SWang Nan 1010fca08f32SWang Nan static unsigned long test_check_cc(int cc, unsigned long cpsr) 1011fca08f32SWang Nan { 1012fca08f32SWang Nan int ret = arm_check_condition(cc << 28, cpsr); 1013fca08f32SWang Nan 1014fca08f32SWang Nan return (ret != ARM_OPCODE_CONDTEST_FAIL); 1015fca08f32SWang Nan } 1016fca08f32SWang Nan 1017fca08f32SWang Nan static int is_last_scenario; 1018fca08f32SWang Nan static int probe_should_run; /* 0 = no, 1 = yes, -1 = unknown */ 1019fca08f32SWang Nan static int memory_needs_checking; 1020fca08f32SWang Nan 1021fca08f32SWang Nan static unsigned long test_context_cpsr(int scenario) 1022fca08f32SWang Nan { 1023fca08f32SWang Nan unsigned long cpsr; 1024fca08f32SWang Nan 1025fca08f32SWang Nan probe_should_run = 1; 1026fca08f32SWang Nan 1027fca08f32SWang Nan /* Default case is that we cycle through 16 combinations of flags */ 1028fca08f32SWang Nan cpsr = (scenario & 0xf) << 28; /* N,Z,C,V flags */ 1029fca08f32SWang Nan cpsr |= (scenario & 0xf) << 16; /* GE flags */ 1030fca08f32SWang Nan cpsr |= (scenario & 0x1) << 27; /* Toggle Q flag */ 1031fca08f32SWang Nan 1032fca08f32SWang Nan if (!test_case_is_thumb) { 1033fca08f32SWang Nan /* Testing ARM code */ 1034fca08f32SWang Nan int cc = current_instruction >> 28; 1035fca08f32SWang Nan 1036fca08f32SWang Nan probe_should_run = test_check_cc(cc, cpsr) != 0; 1037fca08f32SWang Nan if (scenario == 15) 1038fca08f32SWang Nan is_last_scenario = true; 1039fca08f32SWang Nan 1040fca08f32SWang Nan } else if (kprobe_test_flags & TEST_FLAG_NO_ITBLOCK) { 1041fca08f32SWang Nan /* Testing Thumb code without setting ITSTATE */ 1042fca08f32SWang Nan if (kprobe_test_cc_position) { 1043fca08f32SWang Nan int cc = (current_instruction >> kprobe_test_cc_position) & 0xf; 1044fca08f32SWang Nan probe_should_run = test_check_cc(cc, cpsr) != 0; 1045fca08f32SWang Nan } 1046fca08f32SWang Nan 1047fca08f32SWang Nan if (scenario == 15) 1048fca08f32SWang Nan is_last_scenario = true; 1049fca08f32SWang Nan 1050fca08f32SWang Nan } else if (kprobe_test_flags & TEST_FLAG_FULL_ITBLOCK) { 1051fca08f32SWang Nan /* Testing Thumb code with all combinations of ITSTATE */ 1052fca08f32SWang Nan unsigned x = (scenario >> 4); 1053fca08f32SWang Nan unsigned cond_base = x % 7; /* ITSTATE<7:5> */ 1054fca08f32SWang Nan unsigned mask = x / 7 + 2; /* ITSTATE<4:0>, bits reversed */ 1055fca08f32SWang Nan 1056fca08f32SWang Nan if (mask > 0x1f) { 1057fca08f32SWang Nan /* Finish by testing state from instruction 'itt al' */ 1058fca08f32SWang Nan cond_base = 7; 1059fca08f32SWang Nan mask = 0x4; 1060fca08f32SWang Nan if ((scenario & 0xf) == 0xf) 1061fca08f32SWang Nan is_last_scenario = true; 1062fca08f32SWang Nan } 1063fca08f32SWang Nan 1064fca08f32SWang Nan cpsr |= cond_base << 13; /* ITSTATE<7:5> */ 1065fca08f32SWang Nan cpsr |= (mask & 0x1) << 12; /* ITSTATE<4> */ 1066fca08f32SWang Nan cpsr |= (mask & 0x2) << 10; /* ITSTATE<3> */ 1067fca08f32SWang Nan cpsr |= (mask & 0x4) << 8; /* ITSTATE<2> */ 1068fca08f32SWang Nan cpsr |= (mask & 0x8) << 23; /* ITSTATE<1> */ 1069fca08f32SWang Nan cpsr |= (mask & 0x10) << 21; /* ITSTATE<0> */ 1070fca08f32SWang Nan 1071fca08f32SWang Nan probe_should_run = test_check_cc((cpsr >> 12) & 0xf, cpsr) != 0; 1072fca08f32SWang Nan 1073fca08f32SWang Nan } else { 1074fca08f32SWang Nan /* Testing Thumb code with several combinations of ITSTATE */ 1075fca08f32SWang Nan switch (scenario) { 1076fca08f32SWang Nan case 16: /* Clear NZCV flags and 'it eq' state (false as Z=0) */ 1077fca08f32SWang Nan cpsr = 0x00000800; 1078fca08f32SWang Nan probe_should_run = 0; 1079fca08f32SWang Nan break; 1080fca08f32SWang Nan case 17: /* Set NZCV flags and 'it vc' state (false as V=1) */ 1081fca08f32SWang Nan cpsr = 0xf0007800; 1082fca08f32SWang Nan probe_should_run = 0; 1083fca08f32SWang Nan break; 1084fca08f32SWang Nan case 18: /* Clear NZCV flags and 'it ls' state (true as C=0) */ 1085fca08f32SWang Nan cpsr = 0x00009800; 1086fca08f32SWang Nan break; 1087fca08f32SWang Nan case 19: /* Set NZCV flags and 'it cs' state (true as C=1) */ 1088fca08f32SWang Nan cpsr = 0xf0002800; 1089fca08f32SWang Nan is_last_scenario = true; 1090fca08f32SWang Nan break; 1091fca08f32SWang Nan } 1092fca08f32SWang Nan } 1093fca08f32SWang Nan 1094fca08f32SWang Nan return cpsr; 1095fca08f32SWang Nan } 1096fca08f32SWang Nan 1097fca08f32SWang Nan static void setup_test_context(struct pt_regs *regs) 1098fca08f32SWang Nan { 1099fca08f32SWang Nan int scenario = test_case_run_count>>1; 1100fca08f32SWang Nan unsigned long val; 1101fca08f32SWang Nan struct test_arg *args; 1102fca08f32SWang Nan int i; 1103fca08f32SWang Nan 1104fca08f32SWang Nan is_last_scenario = false; 1105fca08f32SWang Nan memory_needs_checking = false; 1106fca08f32SWang Nan 1107fca08f32SWang Nan /* Initialise test memory on stack */ 1108fca08f32SWang Nan val = (scenario & 1) ? VALM : ~VALM; 1109fca08f32SWang Nan for (i = 0; i < TEST_MEMORY_SIZE / sizeof(current_stack[0]); ++i) 1110fca08f32SWang Nan current_stack[i] = val + (i << 8); 1111fca08f32SWang Nan /* Put target of branch on stack for tests which load PC from memory */ 1112fca08f32SWang Nan if (current_branch_target) 1113fca08f32SWang Nan current_stack[15] = current_branch_target; 1114fca08f32SWang Nan /* Put a value for SP on stack for tests which load SP from memory */ 1115fca08f32SWang Nan current_stack[13] = (u32)current_stack + 120; 1116fca08f32SWang Nan 1117fca08f32SWang Nan /* Initialise register values to their default state */ 1118fca08f32SWang Nan val = (scenario & 2) ? VALR : ~VALR; 1119fca08f32SWang Nan for (i = 0; i < 13; ++i) 1120fca08f32SWang Nan regs->uregs[i] = val ^ (i << 8); 1121fca08f32SWang Nan regs->ARM_lr = val ^ (14 << 8); 1122fca08f32SWang Nan regs->ARM_cpsr &= ~(APSR_MASK | PSR_IT_MASK); 1123fca08f32SWang Nan regs->ARM_cpsr |= test_context_cpsr(scenario); 1124fca08f32SWang Nan 1125fca08f32SWang Nan /* Perform testcase specific register setup */ 1126fca08f32SWang Nan args = current_args; 1127fca08f32SWang Nan for (; args[0].type != ARG_TYPE_END; ++args) 1128fca08f32SWang Nan switch (args[0].type) { 1129fca08f32SWang Nan case ARG_TYPE_REG: { 1130fca08f32SWang Nan struct test_arg_regptr *arg = 1131fca08f32SWang Nan (struct test_arg_regptr *)args; 1132fca08f32SWang Nan regs->uregs[arg->reg] = arg->val; 1133fca08f32SWang Nan break; 1134fca08f32SWang Nan } 1135fca08f32SWang Nan case ARG_TYPE_PTR: { 1136fca08f32SWang Nan struct test_arg_regptr *arg = 1137fca08f32SWang Nan (struct test_arg_regptr *)args; 1138fca08f32SWang Nan regs->uregs[arg->reg] = 1139fca08f32SWang Nan (unsigned long)current_stack + arg->val; 1140fca08f32SWang Nan memory_needs_checking = true; 11418d257e95SJon Medhurst (Tixy) /* 11428d257e95SJon Medhurst (Tixy) * Test memory at an address below SP is in danger of 11438d257e95SJon Medhurst (Tixy) * being altered by an interrupt occurring and pushing 11448d257e95SJon Medhurst (Tixy) * data onto the stack. Disable interrupts to stop this. 11458d257e95SJon Medhurst (Tixy) */ 11468d257e95SJon Medhurst (Tixy) if (arg->reg == 13) 11478d257e95SJon Medhurst (Tixy) regs->ARM_cpsr |= PSR_I_BIT; 1148fca08f32SWang Nan break; 1149fca08f32SWang Nan } 1150fca08f32SWang Nan case ARG_TYPE_MEM: { 1151fca08f32SWang Nan struct test_arg_mem *arg = (struct test_arg_mem *)args; 1152fca08f32SWang Nan current_stack[arg->index] = arg->val; 1153fca08f32SWang Nan break; 1154fca08f32SWang Nan } 1155fca08f32SWang Nan default: 1156fca08f32SWang Nan break; 1157fca08f32SWang Nan } 1158fca08f32SWang Nan } 1159fca08f32SWang Nan 1160fca08f32SWang Nan struct test_probe { 1161fca08f32SWang Nan struct kprobe kprobe; 1162fca08f32SWang Nan bool registered; 1163fca08f32SWang Nan int hit; 1164fca08f32SWang Nan }; 1165fca08f32SWang Nan 1166fca08f32SWang Nan static void unregister_test_probe(struct test_probe *probe) 1167fca08f32SWang Nan { 1168fca08f32SWang Nan if (probe->registered) { 1169fca08f32SWang Nan unregister_kprobe(&probe->kprobe); 1170fca08f32SWang Nan probe->kprobe.flags = 0; /* Clear disable flag to allow reuse */ 1171fca08f32SWang Nan } 1172fca08f32SWang Nan probe->registered = false; 1173fca08f32SWang Nan } 1174fca08f32SWang Nan 1175fca08f32SWang Nan static int register_test_probe(struct test_probe *probe) 1176fca08f32SWang Nan { 1177fca08f32SWang Nan int ret; 1178fca08f32SWang Nan 1179fca08f32SWang Nan if (probe->registered) 1180fca08f32SWang Nan BUG(); 1181fca08f32SWang Nan 1182fca08f32SWang Nan ret = register_kprobe(&probe->kprobe); 1183fca08f32SWang Nan if (ret >= 0) { 1184fca08f32SWang Nan probe->registered = true; 1185fca08f32SWang Nan probe->hit = -1; 1186fca08f32SWang Nan } 1187fca08f32SWang Nan return ret; 1188fca08f32SWang Nan } 1189fca08f32SWang Nan 1190fca08f32SWang Nan static int __kprobes 1191fca08f32SWang Nan test_before_pre_handler(struct kprobe *p, struct pt_regs *regs) 1192fca08f32SWang Nan { 1193fca08f32SWang Nan container_of(p, struct test_probe, kprobe)->hit = test_instance; 1194fca08f32SWang Nan return 0; 1195fca08f32SWang Nan } 1196fca08f32SWang Nan 1197fca08f32SWang Nan static void __kprobes 1198fca08f32SWang Nan test_before_post_handler(struct kprobe *p, struct pt_regs *regs, 1199fca08f32SWang Nan unsigned long flags) 1200fca08f32SWang Nan { 1201fca08f32SWang Nan setup_test_context(regs); 1202fca08f32SWang Nan initial_regs = *regs; 1203fca08f32SWang Nan initial_regs.ARM_cpsr &= ~PSR_IGNORE_BITS; 1204fca08f32SWang Nan } 1205fca08f32SWang Nan 1206fca08f32SWang Nan static int __kprobes 1207fca08f32SWang Nan test_case_pre_handler(struct kprobe *p, struct pt_regs *regs) 1208fca08f32SWang Nan { 1209fca08f32SWang Nan container_of(p, struct test_probe, kprobe)->hit = test_instance; 1210fca08f32SWang Nan return 0; 1211fca08f32SWang Nan } 1212fca08f32SWang Nan 1213fca08f32SWang Nan static int __kprobes 1214fca08f32SWang Nan test_after_pre_handler(struct kprobe *p, struct pt_regs *regs) 1215fca08f32SWang Nan { 12164cd872d9SJon Medhurst (Tixy) struct test_arg *args; 12174cd872d9SJon Medhurst (Tixy) 1218fca08f32SWang Nan if (container_of(p, struct test_probe, kprobe)->hit == test_instance) 1219fca08f32SWang Nan return 0; /* Already run for this test instance */ 1220fca08f32SWang Nan 1221fca08f32SWang Nan result_regs = *regs; 12224cd872d9SJon Medhurst (Tixy) 12234cd872d9SJon Medhurst (Tixy) /* Mask out results which are indeterminate */ 1224fca08f32SWang Nan result_regs.ARM_cpsr &= ~PSR_IGNORE_BITS; 12254cd872d9SJon Medhurst (Tixy) for (args = current_args; args[0].type != ARG_TYPE_END; ++args) 12264cd872d9SJon Medhurst (Tixy) if (args[0].type == ARG_TYPE_REG_MASKED) { 12274cd872d9SJon Medhurst (Tixy) struct test_arg_regptr *arg = 12284cd872d9SJon Medhurst (Tixy) (struct test_arg_regptr *)args; 12294cd872d9SJon Medhurst (Tixy) result_regs.uregs[arg->reg] &= arg->val; 12304cd872d9SJon Medhurst (Tixy) } 1231fca08f32SWang Nan 1232fca08f32SWang Nan /* Undo any changes done to SP by the test case */ 1233fca08f32SWang Nan regs->ARM_sp = (unsigned long)current_stack; 12348d257e95SJon Medhurst (Tixy) /* Enable interrupts in case setup_test_context disabled them */ 12358d257e95SJon Medhurst (Tixy) regs->ARM_cpsr &= ~PSR_I_BIT; 1236fca08f32SWang Nan 1237fca08f32SWang Nan container_of(p, struct test_probe, kprobe)->hit = test_instance; 1238fca08f32SWang Nan return 0; 1239fca08f32SWang Nan } 1240fca08f32SWang Nan 1241fca08f32SWang Nan static struct test_probe test_before_probe = { 1242fca08f32SWang Nan .kprobe.pre_handler = test_before_pre_handler, 1243fca08f32SWang Nan .kprobe.post_handler = test_before_post_handler, 1244fca08f32SWang Nan }; 1245fca08f32SWang Nan 1246fca08f32SWang Nan static struct test_probe test_case_probe = { 1247fca08f32SWang Nan .kprobe.pre_handler = test_case_pre_handler, 1248fca08f32SWang Nan }; 1249fca08f32SWang Nan 1250fca08f32SWang Nan static struct test_probe test_after_probe = { 1251fca08f32SWang Nan .kprobe.pre_handler = test_after_pre_handler, 1252fca08f32SWang Nan }; 1253fca08f32SWang Nan 1254fca08f32SWang Nan static struct test_probe test_after2_probe = { 1255fca08f32SWang Nan .kprobe.pre_handler = test_after_pre_handler, 1256fca08f32SWang Nan }; 1257fca08f32SWang Nan 1258fca08f32SWang Nan static void test_case_cleanup(void) 1259fca08f32SWang Nan { 1260fca08f32SWang Nan unregister_test_probe(&test_before_probe); 1261fca08f32SWang Nan unregister_test_probe(&test_case_probe); 1262fca08f32SWang Nan unregister_test_probe(&test_after_probe); 1263fca08f32SWang Nan unregister_test_probe(&test_after2_probe); 1264fca08f32SWang Nan } 1265fca08f32SWang Nan 1266fca08f32SWang Nan static void print_registers(struct pt_regs *regs) 1267fca08f32SWang Nan { 1268fca08f32SWang Nan pr_err("r0 %08lx | r1 %08lx | r2 %08lx | r3 %08lx\n", 1269fca08f32SWang Nan regs->ARM_r0, regs->ARM_r1, regs->ARM_r2, regs->ARM_r3); 1270fca08f32SWang Nan pr_err("r4 %08lx | r5 %08lx | r6 %08lx | r7 %08lx\n", 1271fca08f32SWang Nan regs->ARM_r4, regs->ARM_r5, regs->ARM_r6, regs->ARM_r7); 1272fca08f32SWang Nan pr_err("r8 %08lx | r9 %08lx | r10 %08lx | r11 %08lx\n", 1273fca08f32SWang Nan regs->ARM_r8, regs->ARM_r9, regs->ARM_r10, regs->ARM_fp); 1274fca08f32SWang Nan pr_err("r12 %08lx | sp %08lx | lr %08lx | pc %08lx\n", 1275fca08f32SWang Nan regs->ARM_ip, regs->ARM_sp, regs->ARM_lr, regs->ARM_pc); 1276fca08f32SWang Nan pr_err("cpsr %08lx\n", regs->ARM_cpsr); 1277fca08f32SWang Nan } 1278fca08f32SWang Nan 1279fca08f32SWang Nan static void print_memory(u32 *mem, size_t size) 1280fca08f32SWang Nan { 1281fca08f32SWang Nan int i; 1282fca08f32SWang Nan for (i = 0; i < size / sizeof(u32); i += 4) 1283fca08f32SWang Nan pr_err("%08x %08x %08x %08x\n", mem[i], mem[i+1], 1284fca08f32SWang Nan mem[i+2], mem[i+3]); 1285fca08f32SWang Nan } 1286fca08f32SWang Nan 1287fca08f32SWang Nan static size_t expected_memory_size(u32 *sp) 1288fca08f32SWang Nan { 1289fca08f32SWang Nan size_t size = sizeof(expected_memory); 1290fca08f32SWang Nan int offset = (uintptr_t)sp - (uintptr_t)current_stack; 1291fca08f32SWang Nan if (offset > 0) 1292fca08f32SWang Nan size -= offset; 1293fca08f32SWang Nan return size; 1294fca08f32SWang Nan } 1295fca08f32SWang Nan 1296fca08f32SWang Nan static void test_case_failed(const char *message) 1297fca08f32SWang Nan { 1298fca08f32SWang Nan test_case_cleanup(); 1299fca08f32SWang Nan 1300fca08f32SWang Nan pr_err("FAIL: %s\n", message); 1301fca08f32SWang Nan pr_err("FAIL: Test %s\n", current_title); 1302fca08f32SWang Nan pr_err("FAIL: Scenario %d\n", test_case_run_count >> 1); 1303fca08f32SWang Nan } 1304fca08f32SWang Nan 1305fca08f32SWang Nan static unsigned long next_instruction(unsigned long pc) 1306fca08f32SWang Nan { 1307fca08f32SWang Nan #ifdef CONFIG_THUMB2_KERNEL 1308fca08f32SWang Nan if ((pc & 1) && 1309fca08f32SWang Nan !is_wide_instruction(__mem_to_opcode_thumb16(*(u16 *)(pc - 1)))) 1310fca08f32SWang Nan return pc + 2; 1311fca08f32SWang Nan else 1312fca08f32SWang Nan #endif 1313fca08f32SWang Nan return pc + 4; 1314fca08f32SWang Nan } 1315fca08f32SWang Nan 1316fca08f32SWang Nan static uintptr_t __used kprobes_test_case_start(const char **title, void *stack) 1317fca08f32SWang Nan { 1318fca08f32SWang Nan struct test_arg *args; 1319fca08f32SWang Nan struct test_arg_end *end_arg; 1320fca08f32SWang Nan unsigned long test_code; 1321fca08f32SWang Nan 1322fca08f32SWang Nan current_title = *title++; 1323fca08f32SWang Nan args = (struct test_arg *)title; 1324fca08f32SWang Nan current_args = args; 1325fca08f32SWang Nan current_stack = stack; 1326fca08f32SWang Nan 1327fca08f32SWang Nan ++test_try_count; 1328fca08f32SWang Nan 1329fca08f32SWang Nan while (args->type != ARG_TYPE_END) 1330fca08f32SWang Nan ++args; 1331fca08f32SWang Nan end_arg = (struct test_arg_end *)args; 1332fca08f32SWang Nan 1333fca08f32SWang Nan test_code = (unsigned long)(args + 1); /* Code starts after args */ 1334fca08f32SWang Nan 1335fca08f32SWang Nan test_case_is_thumb = end_arg->flags & ARG_FLAG_THUMB; 1336fca08f32SWang Nan if (test_case_is_thumb) 1337fca08f32SWang Nan test_code |= 1; 1338fca08f32SWang Nan 1339fca08f32SWang Nan current_code_start = test_code; 1340fca08f32SWang Nan 1341fca08f32SWang Nan current_branch_target = 0; 1342fca08f32SWang Nan if (end_arg->branch_offset != end_arg->end_offset) 1343fca08f32SWang Nan current_branch_target = test_code + end_arg->branch_offset; 1344fca08f32SWang Nan 1345fca08f32SWang Nan test_code += end_arg->code_offset; 1346fca08f32SWang Nan test_before_probe.kprobe.addr = (kprobe_opcode_t *)test_code; 1347fca08f32SWang Nan 1348fca08f32SWang Nan test_code = next_instruction(test_code); 1349fca08f32SWang Nan test_case_probe.kprobe.addr = (kprobe_opcode_t *)test_code; 1350fca08f32SWang Nan 1351fca08f32SWang Nan if (test_case_is_thumb) { 1352fca08f32SWang Nan u16 *p = (u16 *)(test_code & ~1); 1353fca08f32SWang Nan current_instruction = __mem_to_opcode_thumb16(p[0]); 1354fca08f32SWang Nan if (is_wide_instruction(current_instruction)) { 1355fca08f32SWang Nan u16 instr2 = __mem_to_opcode_thumb16(p[1]); 1356fca08f32SWang Nan current_instruction = __opcode_thumb32_compose(current_instruction, instr2); 1357fca08f32SWang Nan } 1358fca08f32SWang Nan } else { 1359fca08f32SWang Nan current_instruction = __mem_to_opcode_arm(*(u32 *)test_code); 1360fca08f32SWang Nan } 1361fca08f32SWang Nan 1362fca08f32SWang Nan if (current_title[0] == '.') 1363fca08f32SWang Nan verbose("%s\n", current_title); 1364fca08f32SWang Nan else 1365fca08f32SWang Nan verbose("%s\t@ %0*x\n", current_title, 1366fca08f32SWang Nan test_case_is_thumb ? 4 : 8, 1367fca08f32SWang Nan current_instruction); 1368fca08f32SWang Nan 1369fca08f32SWang Nan test_code = next_instruction(test_code); 1370fca08f32SWang Nan test_after_probe.kprobe.addr = (kprobe_opcode_t *)test_code; 1371fca08f32SWang Nan 1372fca08f32SWang Nan if (kprobe_test_flags & TEST_FLAG_NARROW_INSTR) { 1373fca08f32SWang Nan if (!test_case_is_thumb || 1374fca08f32SWang Nan is_wide_instruction(current_instruction)) { 1375fca08f32SWang Nan test_case_failed("expected 16-bit instruction"); 1376fca08f32SWang Nan goto fail; 1377fca08f32SWang Nan } 1378fca08f32SWang Nan } else { 1379fca08f32SWang Nan if (test_case_is_thumb && 1380fca08f32SWang Nan !is_wide_instruction(current_instruction)) { 1381fca08f32SWang Nan test_case_failed("expected 32-bit instruction"); 1382fca08f32SWang Nan goto fail; 1383fca08f32SWang Nan } 1384fca08f32SWang Nan } 1385fca08f32SWang Nan 1386fca08f32SWang Nan coverage_add(current_instruction); 1387fca08f32SWang Nan 1388fca08f32SWang Nan if (end_arg->flags & ARG_FLAG_UNSUPPORTED) { 1389fca08f32SWang Nan if (register_test_probe(&test_case_probe) < 0) 1390fca08f32SWang Nan goto pass; 1391fca08f32SWang Nan test_case_failed("registered probe for unsupported instruction"); 1392fca08f32SWang Nan goto fail; 1393fca08f32SWang Nan } 1394fca08f32SWang Nan 1395fca08f32SWang Nan if (end_arg->flags & ARG_FLAG_SUPPORTED) { 1396fca08f32SWang Nan if (register_test_probe(&test_case_probe) >= 0) 1397fca08f32SWang Nan goto pass; 1398fca08f32SWang Nan test_case_failed("couldn't register probe for supported instruction"); 1399fca08f32SWang Nan goto fail; 1400fca08f32SWang Nan } 1401fca08f32SWang Nan 1402fca08f32SWang Nan if (register_test_probe(&test_before_probe) < 0) { 1403fca08f32SWang Nan test_case_failed("register test_before_probe failed"); 1404fca08f32SWang Nan goto fail; 1405fca08f32SWang Nan } 1406fca08f32SWang Nan if (register_test_probe(&test_after_probe) < 0) { 1407fca08f32SWang Nan test_case_failed("register test_after_probe failed"); 1408fca08f32SWang Nan goto fail; 1409fca08f32SWang Nan } 1410fca08f32SWang Nan if (current_branch_target) { 1411fca08f32SWang Nan test_after2_probe.kprobe.addr = 1412fca08f32SWang Nan (kprobe_opcode_t *)current_branch_target; 1413fca08f32SWang Nan if (register_test_probe(&test_after2_probe) < 0) { 1414fca08f32SWang Nan test_case_failed("register test_after2_probe failed"); 1415fca08f32SWang Nan goto fail; 1416fca08f32SWang Nan } 1417fca08f32SWang Nan } 1418fca08f32SWang Nan 1419fca08f32SWang Nan /* Start first run of test case */ 1420fca08f32SWang Nan test_case_run_count = 0; 1421fca08f32SWang Nan ++test_instance; 1422fca08f32SWang Nan return current_code_start; 1423fca08f32SWang Nan pass: 1424fca08f32SWang Nan test_case_run_count = TEST_CASE_PASSED; 1425fca08f32SWang Nan return (uintptr_t)test_after_probe.kprobe.addr; 1426fca08f32SWang Nan fail: 1427fca08f32SWang Nan test_case_run_count = TEST_CASE_FAILED; 1428fca08f32SWang Nan return (uintptr_t)test_after_probe.kprobe.addr; 1429fca08f32SWang Nan } 1430fca08f32SWang Nan 1431fca08f32SWang Nan static bool check_test_results(void) 1432fca08f32SWang Nan { 1433fca08f32SWang Nan size_t mem_size = 0; 1434fca08f32SWang Nan u32 *mem = 0; 1435fca08f32SWang Nan 1436fca08f32SWang Nan if (memcmp(&expected_regs, &result_regs, sizeof(expected_regs))) { 1437fca08f32SWang Nan test_case_failed("registers differ"); 1438fca08f32SWang Nan goto fail; 1439fca08f32SWang Nan } 1440fca08f32SWang Nan 1441fca08f32SWang Nan if (memory_needs_checking) { 1442fca08f32SWang Nan mem = (u32 *)result_regs.ARM_sp; 1443fca08f32SWang Nan mem_size = expected_memory_size(mem); 1444fca08f32SWang Nan if (memcmp(expected_memory, mem, mem_size)) { 1445fca08f32SWang Nan test_case_failed("test memory differs"); 1446fca08f32SWang Nan goto fail; 1447fca08f32SWang Nan } 1448fca08f32SWang Nan } 1449fca08f32SWang Nan 1450fca08f32SWang Nan return true; 1451fca08f32SWang Nan 1452fca08f32SWang Nan fail: 1453fca08f32SWang Nan pr_err("initial_regs:\n"); 1454fca08f32SWang Nan print_registers(&initial_regs); 1455fca08f32SWang Nan pr_err("expected_regs:\n"); 1456fca08f32SWang Nan print_registers(&expected_regs); 1457fca08f32SWang Nan pr_err("result_regs:\n"); 1458fca08f32SWang Nan print_registers(&result_regs); 1459fca08f32SWang Nan 1460fca08f32SWang Nan if (mem) { 1461fca08f32SWang Nan pr_err("expected_memory:\n"); 1462fca08f32SWang Nan print_memory(expected_memory, mem_size); 1463fca08f32SWang Nan pr_err("result_memory:\n"); 1464fca08f32SWang Nan print_memory(mem, mem_size); 1465fca08f32SWang Nan } 1466fca08f32SWang Nan 1467fca08f32SWang Nan return false; 1468fca08f32SWang Nan } 1469fca08f32SWang Nan 1470fca08f32SWang Nan static uintptr_t __used kprobes_test_case_end(void) 1471fca08f32SWang Nan { 1472fca08f32SWang Nan if (test_case_run_count < 0) { 1473fca08f32SWang Nan if (test_case_run_count == TEST_CASE_PASSED) 1474fca08f32SWang Nan /* kprobes_test_case_start did all the needed testing */ 1475fca08f32SWang Nan goto pass; 1476fca08f32SWang Nan else 1477fca08f32SWang Nan /* kprobes_test_case_start failed */ 1478fca08f32SWang Nan goto fail; 1479fca08f32SWang Nan } 1480fca08f32SWang Nan 1481fca08f32SWang Nan if (test_before_probe.hit != test_instance) { 1482fca08f32SWang Nan test_case_failed("test_before_handler not run"); 1483fca08f32SWang Nan goto fail; 1484fca08f32SWang Nan } 1485fca08f32SWang Nan 1486fca08f32SWang Nan if (test_after_probe.hit != test_instance && 1487fca08f32SWang Nan test_after2_probe.hit != test_instance) { 1488fca08f32SWang Nan test_case_failed("test_after_handler not run"); 1489fca08f32SWang Nan goto fail; 1490fca08f32SWang Nan } 1491fca08f32SWang Nan 1492fca08f32SWang Nan /* 1493fca08f32SWang Nan * Even numbered test runs ran without a probe on the test case so 1494fca08f32SWang Nan * we can gather reference results. The subsequent odd numbered run 1495fca08f32SWang Nan * will have the probe inserted. 1496fca08f32SWang Nan */ 1497fca08f32SWang Nan if ((test_case_run_count & 1) == 0) { 1498fca08f32SWang Nan /* Save results from run without probe */ 1499fca08f32SWang Nan u32 *mem = (u32 *)result_regs.ARM_sp; 1500fca08f32SWang Nan expected_regs = result_regs; 1501fca08f32SWang Nan memcpy(expected_memory, mem, expected_memory_size(mem)); 1502fca08f32SWang Nan 1503fca08f32SWang Nan /* Insert probe onto test case instruction */ 1504fca08f32SWang Nan if (register_test_probe(&test_case_probe) < 0) { 1505fca08f32SWang Nan test_case_failed("register test_case_probe failed"); 1506fca08f32SWang Nan goto fail; 1507fca08f32SWang Nan } 1508fca08f32SWang Nan } else { 1509fca08f32SWang Nan /* Check probe ran as expected */ 1510fca08f32SWang Nan if (probe_should_run == 1) { 1511fca08f32SWang Nan if (test_case_probe.hit != test_instance) { 1512fca08f32SWang Nan test_case_failed("test_case_handler not run"); 1513fca08f32SWang Nan goto fail; 1514fca08f32SWang Nan } 1515fca08f32SWang Nan } else if (probe_should_run == 0) { 1516fca08f32SWang Nan if (test_case_probe.hit == test_instance) { 1517fca08f32SWang Nan test_case_failed("test_case_handler ran"); 1518fca08f32SWang Nan goto fail; 1519fca08f32SWang Nan } 1520fca08f32SWang Nan } 1521fca08f32SWang Nan 1522fca08f32SWang Nan /* Remove probe for any subsequent reference run */ 1523fca08f32SWang Nan unregister_test_probe(&test_case_probe); 1524fca08f32SWang Nan 1525fca08f32SWang Nan if (!check_test_results()) 1526fca08f32SWang Nan goto fail; 1527fca08f32SWang Nan 1528fca08f32SWang Nan if (is_last_scenario) 1529fca08f32SWang Nan goto pass; 1530fca08f32SWang Nan } 1531fca08f32SWang Nan 1532fca08f32SWang Nan /* Do next test run */ 1533fca08f32SWang Nan ++test_case_run_count; 1534fca08f32SWang Nan ++test_instance; 1535fca08f32SWang Nan return current_code_start; 1536fca08f32SWang Nan fail: 1537fca08f32SWang Nan ++test_fail_count; 1538fca08f32SWang Nan goto end; 1539fca08f32SWang Nan pass: 1540fca08f32SWang Nan ++test_pass_count; 1541fca08f32SWang Nan end: 1542fca08f32SWang Nan test_case_cleanup(); 1543fca08f32SWang Nan return 0; 1544fca08f32SWang Nan } 1545fca08f32SWang Nan 1546fca08f32SWang Nan 1547fca08f32SWang Nan /* 1548fca08f32SWang Nan * Top level test functions 1549fca08f32SWang Nan */ 1550fca08f32SWang Nan 1551fca08f32SWang Nan static int run_test_cases(void (*tests)(void), const union decode_item *table) 1552fca08f32SWang Nan { 1553fca08f32SWang Nan int ret; 1554fca08f32SWang Nan 1555fca08f32SWang Nan pr_info(" Check decoding tables\n"); 1556fca08f32SWang Nan ret = table_test(table); 1557fca08f32SWang Nan if (ret) 1558fca08f32SWang Nan return ret; 1559fca08f32SWang Nan 1560fca08f32SWang Nan pr_info(" Run test cases\n"); 1561fca08f32SWang Nan ret = coverage_start(table); 1562fca08f32SWang Nan if (ret) 1563fca08f32SWang Nan return ret; 1564fca08f32SWang Nan 1565fca08f32SWang Nan tests(); 1566fca08f32SWang Nan 1567fca08f32SWang Nan coverage_end(); 1568fca08f32SWang Nan return 0; 1569fca08f32SWang Nan } 1570fca08f32SWang Nan 1571fca08f32SWang Nan 1572fca08f32SWang Nan static int __init run_all_tests(void) 1573fca08f32SWang Nan { 1574fca08f32SWang Nan int ret = 0; 1575fca08f32SWang Nan 1576fca08f32SWang Nan pr_info("Beginning kprobe tests...\n"); 1577fca08f32SWang Nan 1578fca08f32SWang Nan #ifndef CONFIG_THUMB2_KERNEL 1579fca08f32SWang Nan 1580fca08f32SWang Nan pr_info("Probe ARM code\n"); 1581fca08f32SWang Nan ret = run_api_tests(arm_func); 1582fca08f32SWang Nan if (ret) 1583fca08f32SWang Nan goto out; 1584fca08f32SWang Nan 1585fca08f32SWang Nan pr_info("ARM instruction simulation\n"); 1586fca08f32SWang Nan ret = run_test_cases(kprobe_arm_test_cases, probes_decode_arm_table); 1587fca08f32SWang Nan if (ret) 1588fca08f32SWang Nan goto out; 1589fca08f32SWang Nan 1590fca08f32SWang Nan #else /* CONFIG_THUMB2_KERNEL */ 1591fca08f32SWang Nan 1592fca08f32SWang Nan pr_info("Probe 16-bit Thumb code\n"); 1593fca08f32SWang Nan ret = run_api_tests(thumb16_func); 1594fca08f32SWang Nan if (ret) 1595fca08f32SWang Nan goto out; 1596fca08f32SWang Nan 1597fca08f32SWang Nan pr_info("Probe 32-bit Thumb code, even halfword\n"); 1598fca08f32SWang Nan ret = run_api_tests(thumb32even_func); 1599fca08f32SWang Nan if (ret) 1600fca08f32SWang Nan goto out; 1601fca08f32SWang Nan 1602fca08f32SWang Nan pr_info("Probe 32-bit Thumb code, odd halfword\n"); 1603fca08f32SWang Nan ret = run_api_tests(thumb32odd_func); 1604fca08f32SWang Nan if (ret) 1605fca08f32SWang Nan goto out; 1606fca08f32SWang Nan 1607fca08f32SWang Nan pr_info("16-bit Thumb instruction simulation\n"); 1608fca08f32SWang Nan ret = run_test_cases(kprobe_thumb16_test_cases, 1609fca08f32SWang Nan probes_decode_thumb16_table); 1610fca08f32SWang Nan if (ret) 1611fca08f32SWang Nan goto out; 1612fca08f32SWang Nan 1613fca08f32SWang Nan pr_info("32-bit Thumb instruction simulation\n"); 1614fca08f32SWang Nan ret = run_test_cases(kprobe_thumb32_test_cases, 1615fca08f32SWang Nan probes_decode_thumb32_table); 1616fca08f32SWang Nan if (ret) 1617fca08f32SWang Nan goto out; 1618fca08f32SWang Nan #endif 1619fca08f32SWang Nan 1620fca08f32SWang Nan pr_info("Total instruction simulation tests=%d, pass=%d fail=%d\n", 1621fca08f32SWang Nan test_try_count, test_pass_count, test_fail_count); 1622fca08f32SWang Nan if (test_fail_count) { 1623fca08f32SWang Nan ret = -EINVAL; 1624fca08f32SWang Nan goto out; 1625fca08f32SWang Nan } 1626fca08f32SWang Nan 1627fca08f32SWang Nan #if BENCHMARKING 1628fca08f32SWang Nan pr_info("Benchmarks\n"); 1629fca08f32SWang Nan ret = run_benchmarks(); 1630fca08f32SWang Nan if (ret) 1631fca08f32SWang Nan goto out; 1632fca08f32SWang Nan #endif 1633fca08f32SWang Nan 1634fca08f32SWang Nan #if __LINUX_ARM_ARCH__ >= 7 1635fca08f32SWang Nan /* We are able to run all test cases so coverage should be complete */ 1636fca08f32SWang Nan if (coverage_fail) { 1637fca08f32SWang Nan pr_err("FAIL: Test coverage checks failed\n"); 1638fca08f32SWang Nan ret = -EINVAL; 1639fca08f32SWang Nan goto out; 1640fca08f32SWang Nan } 1641fca08f32SWang Nan #endif 1642fca08f32SWang Nan 1643fca08f32SWang Nan out: 1644fca08f32SWang Nan if (ret == 0) 1645fca08f32SWang Nan ret = tests_failed; 1646fca08f32SWang Nan if (ret == 0) 1647fca08f32SWang Nan pr_info("Finished kprobe tests OK\n"); 1648fca08f32SWang Nan else 1649fca08f32SWang Nan pr_err("kprobe tests failed\n"); 1650fca08f32SWang Nan 1651fca08f32SWang Nan return ret; 1652fca08f32SWang Nan } 1653fca08f32SWang Nan 1654fca08f32SWang Nan 1655fca08f32SWang Nan /* 1656fca08f32SWang Nan * Module setup 1657fca08f32SWang Nan */ 1658fca08f32SWang Nan 1659fca08f32SWang Nan #ifdef MODULE 1660fca08f32SWang Nan 1661fca08f32SWang Nan static void __exit kprobe_test_exit(void) 1662fca08f32SWang Nan { 1663fca08f32SWang Nan } 1664fca08f32SWang Nan 1665fca08f32SWang Nan module_init(run_all_tests) 1666fca08f32SWang Nan module_exit(kprobe_test_exit) 1667fca08f32SWang Nan MODULE_LICENSE("GPL"); 1668fca08f32SWang Nan 1669fca08f32SWang Nan #else /* !MODULE */ 1670fca08f32SWang Nan 1671fca08f32SWang Nan late_initcall(run_all_tests); 1672fca08f32SWang Nan 1673fca08f32SWang Nan #endif 1674