1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3 * 4 * Copyright (C) 2018 The FreeBSD Foundation. All rights reserved. 5 * Copyright (C) 2018, 2019 Andrew Turner 6 * 7 * This software was developed by Mitchell Horne under sponsorship of 8 * the FreeBSD Foundation. 9 * 10 * This software was developed by SRI International and the University of 11 * Cambridge Computer Laboratory under DARPA/AFRL contract FA8750-10-C-0237 12 * ("CTSRD"), as part of the DARPA CRASH research programme. 13 * 14 * Redistribution and use in source and binary forms, with or without 15 * modification, are permitted provided that the following conditions 16 * are met: 17 * 1. Redistributions of source code must retain the above copyright 18 * notice, this list of conditions and the following disclaimer. 19 * 2. Redistributions in binary form must reproduce the above copyright 20 * notice, this list of conditions and the following disclaimer in the 21 * documentation and/or other materials provided with the distribution. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 * 35 * $FreeBSD$ 36 */ 37 38 #ifdef KCSAN 39 #define SAN_RUNTIME 40 #endif 41 42 #include <sys/cdefs.h> 43 __FBSDID("$FreeBSD$"); 44 45 #include <sys/param.h> 46 #include <sys/coverage.h> 47 48 #include <machine/atomic.h> 49 50 void __sanitizer_cov_trace_pc(void); 51 void __sanitizer_cov_trace_cmp1(uint8_t, uint8_t); 52 void __sanitizer_cov_trace_cmp2(uint16_t, uint16_t); 53 void __sanitizer_cov_trace_cmp4(uint32_t, uint32_t); 54 void __sanitizer_cov_trace_cmp8(uint64_t, uint64_t); 55 void __sanitizer_cov_trace_const_cmp1(uint8_t, uint8_t); 56 void __sanitizer_cov_trace_const_cmp2(uint16_t, uint16_t); 57 void __sanitizer_cov_trace_const_cmp4(uint32_t, uint32_t); 58 void __sanitizer_cov_trace_const_cmp8(uint64_t, uint64_t); 59 void __sanitizer_cov_trace_switch(uint64_t, uint64_t *); 60 61 static cov_trace_pc_t cov_trace_pc; 62 static cov_trace_cmp_t cov_trace_cmp; 63 64 void 65 cov_register_pc(cov_trace_pc_t trace_pc) 66 { 67 68 atomic_store_ptr(&cov_trace_pc, trace_pc); 69 } 70 71 void 72 cov_unregister_pc(void) 73 { 74 75 atomic_store_ptr(&cov_trace_pc, NULL); 76 } 77 78 void 79 cov_register_cmp(cov_trace_cmp_t trace_cmp) 80 { 81 82 atomic_store_ptr(&cov_trace_cmp, trace_cmp); 83 } 84 85 void 86 cov_unregister_cmp(void) 87 { 88 89 atomic_store_ptr(&cov_trace_cmp, NULL); 90 } 91 92 /* 93 * Main entry point. A call to this function will be inserted 94 * at every edge, and if coverage is enabled for the thread 95 * this function will add the PC to the buffer. 96 */ 97 void 98 __sanitizer_cov_trace_pc(void) 99 { 100 cov_trace_pc_t trace_pc; 101 102 trace_pc = atomic_load_ptr(&cov_trace_pc); 103 if (trace_pc != NULL) 104 trace_pc((uint64_t)__builtin_return_address(0)); 105 } 106 107 /* 108 * Comparison entry points. When the kernel performs a comparison 109 * operation the compiler inserts a call to one of the following 110 * functions to record the operation. 111 */ 112 void 113 __sanitizer_cov_trace_cmp1(uint8_t arg1, uint8_t arg2) 114 { 115 cov_trace_cmp_t trace_cmp; 116 117 trace_cmp = atomic_load_ptr(&cov_trace_cmp); 118 if (trace_cmp != NULL) 119 trace_cmp(COV_CMP_SIZE(0), arg1, arg2, 120 (uint64_t)__builtin_return_address(0)); 121 } 122 123 void 124 __sanitizer_cov_trace_cmp2(uint16_t arg1, uint16_t arg2) 125 { 126 cov_trace_cmp_t trace_cmp; 127 128 trace_cmp = atomic_load_ptr(&cov_trace_cmp); 129 if (trace_cmp != NULL) 130 trace_cmp(COV_CMP_SIZE(1), arg1, arg2, 131 (uint64_t)__builtin_return_address(0)); 132 } 133 134 void 135 __sanitizer_cov_trace_cmp4(uint32_t arg1, uint32_t arg2) 136 { 137 cov_trace_cmp_t trace_cmp; 138 139 trace_cmp = atomic_load_ptr(&cov_trace_cmp); 140 if (trace_cmp != NULL) 141 trace_cmp(COV_CMP_SIZE(2), arg1, arg2, 142 (uint64_t)__builtin_return_address(0)); 143 } 144 145 void 146 __sanitizer_cov_trace_cmp8(uint64_t arg1, uint64_t arg2) 147 { 148 cov_trace_cmp_t trace_cmp; 149 150 trace_cmp = atomic_load_ptr(&cov_trace_cmp); 151 if (trace_cmp != NULL) 152 trace_cmp(COV_CMP_SIZE(3), arg1, arg2, 153 (uint64_t)__builtin_return_address(0)); 154 } 155 156 void 157 __sanitizer_cov_trace_const_cmp1(uint8_t arg1, uint8_t arg2) 158 { 159 cov_trace_cmp_t trace_cmp; 160 161 trace_cmp = atomic_load_ptr(&cov_trace_cmp); 162 if (trace_cmp != NULL) 163 trace_cmp(COV_CMP_SIZE(0) | COV_CMP_CONST, arg1, arg2, 164 (uint64_t)__builtin_return_address(0)); 165 } 166 167 void 168 __sanitizer_cov_trace_const_cmp2(uint16_t arg1, uint16_t arg2) 169 { 170 cov_trace_cmp_t trace_cmp; 171 172 trace_cmp = atomic_load_ptr(&cov_trace_cmp); 173 if (trace_cmp != NULL) 174 trace_cmp(COV_CMP_SIZE(1) | COV_CMP_CONST, arg1, arg2, 175 (uint64_t)__builtin_return_address(0)); 176 } 177 178 void 179 __sanitizer_cov_trace_const_cmp4(uint32_t arg1, uint32_t arg2) 180 { 181 cov_trace_cmp_t trace_cmp; 182 183 trace_cmp = atomic_load_ptr(&cov_trace_cmp); 184 if (trace_cmp != NULL) 185 trace_cmp(COV_CMP_SIZE(2) | COV_CMP_CONST, arg1, arg2, 186 (uint64_t)__builtin_return_address(0)); 187 } 188 189 void 190 __sanitizer_cov_trace_const_cmp8(uint64_t arg1, uint64_t arg2) 191 { 192 cov_trace_cmp_t trace_cmp; 193 194 trace_cmp = atomic_load_ptr(&cov_trace_cmp); 195 if (trace_cmp != NULL) 196 trace_cmp(COV_CMP_SIZE(3) | COV_CMP_CONST, arg1, arg2, 197 (uint64_t)__builtin_return_address(0)); 198 } 199 200 /* 201 * val is the switch operand 202 * cases[0] is the number of case constants 203 * cases[1] is the size of val in bits 204 * cases[2..n] are the case constants 205 */ 206 void 207 __sanitizer_cov_trace_switch(uint64_t val, uint64_t *cases) 208 { 209 uint64_t i, count, ret, type; 210 cov_trace_cmp_t trace_cmp; 211 212 trace_cmp = atomic_load_ptr(&cov_trace_cmp); 213 if (trace_cmp == NULL) 214 return; 215 216 count = cases[0]; 217 ret = (uint64_t)__builtin_return_address(0); 218 219 switch (cases[1]) { 220 case 8: 221 type = COV_CMP_SIZE(0); 222 break; 223 case 16: 224 type = COV_CMP_SIZE(1); 225 break; 226 case 32: 227 type = COV_CMP_SIZE(2); 228 break; 229 case 64: 230 type = COV_CMP_SIZE(3); 231 break; 232 default: 233 return; 234 } 235 236 val |= COV_CMP_CONST; 237 238 for (i = 0; i < count; i++) 239 if (!trace_cmp(type, val, cases[i + 2], ret)) 240 return; 241 } 242