1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * sorttable.c: Sort the kernel's table 4 * 5 * Added ORC unwind tables sort support and other updates: 6 * Copyright (C) 1999-2019 Alibaba Group Holding Limited. by: 7 * Shile Zhang <shile.zhang@linux.alibaba.com> 8 * 9 * Copyright 2011 - 2012 Cavium, Inc. 10 * 11 * Based on code taken from recortmcount.c which is: 12 * 13 * Copyright 2009 John F. Reiser <jreiser@BitWagon.com>. All rights reserved. 14 * 15 * Restructured to fit Linux format, as well as other updates: 16 * Copyright 2010 Steven Rostedt <srostedt@redhat.com>, Red Hat Inc. 17 */ 18 19 /* 20 * Strategy: alter the vmlinux file in-place. 21 */ 22 23 #include <sys/types.h> 24 #include <sys/mman.h> 25 #include <sys/stat.h> 26 #include <getopt.h> 27 #include <elf.h> 28 #include <fcntl.h> 29 #include <stdio.h> 30 #include <stdlib.h> 31 #include <string.h> 32 #include <unistd.h> 33 34 #include <tools/be_byteshift.h> 35 #include <tools/le_byteshift.h> 36 37 #ifndef EM_ARCOMPACT 38 #define EM_ARCOMPACT 93 39 #endif 40 41 #ifndef EM_XTENSA 42 #define EM_XTENSA 94 43 #endif 44 45 #ifndef EM_AARCH64 46 #define EM_AARCH64 183 47 #endif 48 49 #ifndef EM_MICROBLAZE 50 #define EM_MICROBLAZE 189 51 #endif 52 53 #ifndef EM_ARCV2 54 #define EM_ARCV2 195 55 #endif 56 57 #ifndef EM_RISCV 58 #define EM_RISCV 243 59 #endif 60 61 static uint32_t (*r)(const uint32_t *); 62 static uint16_t (*r2)(const uint16_t *); 63 static uint64_t (*r8)(const uint64_t *); 64 static void (*w)(uint32_t, uint32_t *); 65 static void (*w2)(uint16_t, uint16_t *); 66 static void (*w8)(uint64_t, uint64_t *); 67 typedef void (*table_sort_t)(char *, int); 68 69 /* 70 * Get the whole file as a programming convenience in order to avoid 71 * malloc+lseek+read+free of many pieces. If successful, then mmap 72 * avoids copying unused pieces; else just read the whole file. 73 * Open for both read and write. 74 */ 75 static void *mmap_file(char const *fname, size_t *size) 76 { 77 int fd; 78 struct stat sb; 79 void *addr = NULL; 80 81 fd = open(fname, O_RDWR); 82 if (fd < 0) { 83 perror(fname); 84 return NULL; 85 } 86 if (fstat(fd, &sb) < 0) { 87 perror(fname); 88 goto out; 89 } 90 if (!S_ISREG(sb.st_mode)) { 91 fprintf(stderr, "not a regular file: %s\n", fname); 92 goto out; 93 } 94 95 addr = mmap(0, sb.st_size, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0); 96 if (addr == MAP_FAILED) { 97 fprintf(stderr, "Could not mmap file: %s\n", fname); 98 goto out; 99 } 100 101 *size = sb.st_size; 102 103 out: 104 close(fd); 105 return addr; 106 } 107 108 static uint32_t rbe(const uint32_t *x) 109 { 110 return get_unaligned_be32(x); 111 } 112 113 static uint16_t r2be(const uint16_t *x) 114 { 115 return get_unaligned_be16(x); 116 } 117 118 static uint64_t r8be(const uint64_t *x) 119 { 120 return get_unaligned_be64(x); 121 } 122 123 static uint32_t rle(const uint32_t *x) 124 { 125 return get_unaligned_le32(x); 126 } 127 128 static uint16_t r2le(const uint16_t *x) 129 { 130 return get_unaligned_le16(x); 131 } 132 133 static uint64_t r8le(const uint64_t *x) 134 { 135 return get_unaligned_le64(x); 136 } 137 138 static void wbe(uint32_t val, uint32_t *x) 139 { 140 put_unaligned_be32(val, x); 141 } 142 143 static void w2be(uint16_t val, uint16_t *x) 144 { 145 put_unaligned_be16(val, x); 146 } 147 148 static void w8be(uint64_t val, uint64_t *x) 149 { 150 put_unaligned_be64(val, x); 151 } 152 153 static void wle(uint32_t val, uint32_t *x) 154 { 155 put_unaligned_le32(val, x); 156 } 157 158 static void w2le(uint16_t val, uint16_t *x) 159 { 160 put_unaligned_le16(val, x); 161 } 162 163 static void w8le(uint64_t val, uint64_t *x) 164 { 165 put_unaligned_le64(val, x); 166 } 167 168 /* 169 * Move reserved section indices SHN_LORESERVE..SHN_HIRESERVE out of 170 * the way to -256..-1, to avoid conflicting with real section 171 * indices. 172 */ 173 #define SPECIAL(i) ((i) - (SHN_HIRESERVE + 1)) 174 175 static inline int is_shndx_special(unsigned int i) 176 { 177 return i != SHN_XINDEX && i >= SHN_LORESERVE && i <= SHN_HIRESERVE; 178 } 179 180 /* Accessor for sym->st_shndx, hides ugliness of "64k sections" */ 181 static inline unsigned int get_secindex(unsigned int shndx, 182 unsigned int sym_offs, 183 const Elf32_Word *symtab_shndx_start) 184 { 185 if (is_shndx_special(shndx)) 186 return SPECIAL(shndx); 187 if (shndx != SHN_XINDEX) 188 return shndx; 189 return r(&symtab_shndx_start[sym_offs]); 190 } 191 192 /* 32 bit and 64 bit are very similar */ 193 #include "sorttable.h" 194 #define SORTTABLE_64 195 #include "sorttable.h" 196 197 static int compare_relative_table(const void *a, const void *b) 198 { 199 int32_t av = (int32_t)r(a); 200 int32_t bv = (int32_t)r(b); 201 202 if (av < bv) 203 return -1; 204 if (av > bv) 205 return 1; 206 return 0; 207 } 208 209 static void sort_relative_table(char *extab_image, int image_size) 210 { 211 int i = 0; 212 213 /* 214 * Do the same thing the runtime sort does, first normalize to 215 * being relative to the start of the section. 216 */ 217 while (i < image_size) { 218 uint32_t *loc = (uint32_t *)(extab_image + i); 219 w(r(loc) + i, loc); 220 i += 4; 221 } 222 223 qsort(extab_image, image_size / 8, 8, compare_relative_table); 224 225 /* Now denormalize. */ 226 i = 0; 227 while (i < image_size) { 228 uint32_t *loc = (uint32_t *)(extab_image + i); 229 w(r(loc) - i, loc); 230 i += 4; 231 } 232 } 233 234 static void arm64_sort_relative_table(char *extab_image, int image_size) 235 { 236 int i = 0; 237 238 while (i < image_size) { 239 uint32_t *loc = (uint32_t *)(extab_image + i); 240 241 w(r(loc) + i, loc); 242 w(r(loc + 1) + i + 4, loc + 1); 243 /* Don't touch the fixup type or data */ 244 245 i += sizeof(uint32_t) * 3; 246 } 247 248 qsort(extab_image, image_size / 12, 12, compare_relative_table); 249 250 i = 0; 251 while (i < image_size) { 252 uint32_t *loc = (uint32_t *)(extab_image + i); 253 254 w(r(loc) - i, loc); 255 w(r(loc + 1) - (i + 4), loc + 1); 256 /* Don't touch the fixup type or data */ 257 258 i += sizeof(uint32_t) * 3; 259 } 260 } 261 262 static void x86_sort_relative_table(char *extab_image, int image_size) 263 { 264 int i = 0; 265 266 while (i < image_size) { 267 uint32_t *loc = (uint32_t *)(extab_image + i); 268 269 w(r(loc) + i, loc); 270 w(r(loc + 1) + i + 4, loc + 1); 271 /* Don't touch the fixup type */ 272 273 i += sizeof(uint32_t) * 3; 274 } 275 276 qsort(extab_image, image_size / 12, 12, compare_relative_table); 277 278 i = 0; 279 while (i < image_size) { 280 uint32_t *loc = (uint32_t *)(extab_image + i); 281 282 w(r(loc) - i, loc); 283 w(r(loc + 1) - (i + 4), loc + 1); 284 /* Don't touch the fixup type */ 285 286 i += sizeof(uint32_t) * 3; 287 } 288 } 289 290 static void s390_sort_relative_table(char *extab_image, int image_size) 291 { 292 int i; 293 294 for (i = 0; i < image_size; i += 16) { 295 char *loc = extab_image + i; 296 uint64_t handler; 297 298 w(r((uint32_t *)loc) + i, (uint32_t *)loc); 299 w(r((uint32_t *)(loc + 4)) + (i + 4), (uint32_t *)(loc + 4)); 300 /* 301 * 0 is a special self-relative handler value, which means that 302 * handler should be ignored. It is safe, because it means that 303 * handler field points to itself, which should never happen. 304 * When creating extable-relative values, keep it as 0, since 305 * this should never occur either: it would mean that handler 306 * field points to the first extable entry. 307 */ 308 handler = r8((uint64_t *)(loc + 8)); 309 if (handler) 310 handler += i + 8; 311 w8(handler, (uint64_t *)(loc + 8)); 312 } 313 314 qsort(extab_image, image_size / 16, 16, compare_relative_table); 315 316 for (i = 0; i < image_size; i += 16) { 317 char *loc = extab_image + i; 318 uint64_t handler; 319 320 w(r((uint32_t *)loc) - i, (uint32_t *)loc); 321 w(r((uint32_t *)(loc + 4)) - (i + 4), (uint32_t *)(loc + 4)); 322 handler = r8((uint64_t *)(loc + 8)); 323 if (handler) 324 handler -= i + 8; 325 w8(handler, (uint64_t *)(loc + 8)); 326 } 327 } 328 329 static int do_file(char const *const fname, void *addr) 330 { 331 int rc = -1; 332 Elf32_Ehdr *ehdr = addr; 333 table_sort_t custom_sort = NULL; 334 335 switch (ehdr->e_ident[EI_DATA]) { 336 case ELFDATA2LSB: 337 r = rle; 338 r2 = r2le; 339 r8 = r8le; 340 w = wle; 341 w2 = w2le; 342 w8 = w8le; 343 break; 344 case ELFDATA2MSB: 345 r = rbe; 346 r2 = r2be; 347 r8 = r8be; 348 w = wbe; 349 w2 = w2be; 350 w8 = w8be; 351 break; 352 default: 353 fprintf(stderr, "unrecognized ELF data encoding %d: %s\n", 354 ehdr->e_ident[EI_DATA], fname); 355 return -1; 356 } 357 358 if (memcmp(ELFMAG, ehdr->e_ident, SELFMAG) != 0 || 359 (r2(&ehdr->e_type) != ET_EXEC && r2(&ehdr->e_type) != ET_DYN) || 360 ehdr->e_ident[EI_VERSION] != EV_CURRENT) { 361 fprintf(stderr, "unrecognized ET_EXEC/ET_DYN file %s\n", fname); 362 return -1; 363 } 364 365 switch (r2(&ehdr->e_machine)) { 366 case EM_386: 367 case EM_X86_64: 368 custom_sort = x86_sort_relative_table; 369 break; 370 case EM_S390: 371 custom_sort = s390_sort_relative_table; 372 break; 373 case EM_AARCH64: 374 custom_sort = arm64_sort_relative_table; 375 break; 376 case EM_PARISC: 377 case EM_PPC: 378 case EM_PPC64: 379 custom_sort = sort_relative_table; 380 break; 381 case EM_ARCOMPACT: 382 case EM_ARCV2: 383 case EM_ARM: 384 case EM_MICROBLAZE: 385 case EM_MIPS: 386 case EM_RISCV: 387 case EM_XTENSA: 388 break; 389 default: 390 fprintf(stderr, "unrecognized e_machine %d %s\n", 391 r2(&ehdr->e_machine), fname); 392 return -1; 393 } 394 395 switch (ehdr->e_ident[EI_CLASS]) { 396 case ELFCLASS32: 397 if (r2(&ehdr->e_ehsize) != sizeof(Elf32_Ehdr) || 398 r2(&ehdr->e_shentsize) != sizeof(Elf32_Shdr)) { 399 fprintf(stderr, 400 "unrecognized ET_EXEC/ET_DYN file: %s\n", fname); 401 break; 402 } 403 rc = do_sort_32(ehdr, fname, custom_sort); 404 break; 405 case ELFCLASS64: 406 { 407 Elf64_Ehdr *const ghdr = (Elf64_Ehdr *)ehdr; 408 if (r2(&ghdr->e_ehsize) != sizeof(Elf64_Ehdr) || 409 r2(&ghdr->e_shentsize) != sizeof(Elf64_Shdr)) { 410 fprintf(stderr, 411 "unrecognized ET_EXEC/ET_DYN file: %s\n", 412 fname); 413 break; 414 } 415 rc = do_sort_64(ghdr, fname, custom_sort); 416 } 417 break; 418 default: 419 fprintf(stderr, "unrecognized ELF class %d %s\n", 420 ehdr->e_ident[EI_CLASS], fname); 421 break; 422 } 423 424 return rc; 425 } 426 427 int main(int argc, char *argv[]) 428 { 429 int i, n_error = 0; /* gcc-4.3.0 false positive complaint */ 430 size_t size = 0; 431 void *addr = NULL; 432 433 if (argc < 2) { 434 fprintf(stderr, "usage: sorttable vmlinux...\n"); 435 return 0; 436 } 437 438 /* Process each file in turn, allowing deep failure. */ 439 for (i = 1; i < argc; i++) { 440 addr = mmap_file(argv[i], &size); 441 if (!addr) { 442 ++n_error; 443 continue; 444 } 445 446 if (do_file(argv[i], addr)) 447 ++n_error; 448 449 munmap(addr, size); 450 } 451 452 return !!n_error; 453 } 454