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 <[email protected]> 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 <[email protected]>. All rights reserved. 14 * 15 * Restructured to fit Linux format, as well as other updates: 16 * Copyright 2010 Steven Rostedt <[email protected]>, 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 #include <errno.h> 34 #include <pthread.h> 35 36 #include <tools/be_byteshift.h> 37 #include <tools/le_byteshift.h> 38 39 #ifndef EM_ARCOMPACT 40 #define EM_ARCOMPACT 93 41 #endif 42 43 #ifndef EM_XTENSA 44 #define EM_XTENSA 94 45 #endif 46 47 #ifndef EM_AARCH64 48 #define EM_AARCH64 183 49 #endif 50 51 #ifndef EM_MICROBLAZE 52 #define EM_MICROBLAZE 189 53 #endif 54 55 #ifndef EM_ARCV2 56 #define EM_ARCV2 195 57 #endif 58 59 #ifndef EM_RISCV 60 #define EM_RISCV 243 61 #endif 62 63 #ifndef EM_LOONGARCH 64 #define EM_LOONGARCH 258 65 #endif 66 67 typedef union { 68 Elf32_Ehdr e32; 69 Elf64_Ehdr e64; 70 } Elf_Ehdr; 71 72 typedef union { 73 Elf32_Shdr e32; 74 Elf64_Shdr e64; 75 } Elf_Shdr; 76 77 typedef union { 78 Elf32_Sym e32; 79 Elf64_Sym e64; 80 } Elf_Sym; 81 82 static uint32_t (*r)(const uint32_t *); 83 static uint16_t (*r2)(const uint16_t *); 84 static uint64_t (*r8)(const uint64_t *); 85 static void (*w)(uint32_t, uint32_t *); 86 typedef void (*table_sort_t)(char *, int); 87 88 static uint64_t ehdr64_shoff(Elf_Ehdr *ehdr) 89 { 90 return r8(&ehdr->e64.e_shoff); 91 } 92 93 static uint64_t ehdr32_shoff(Elf_Ehdr *ehdr) 94 { 95 return r(&ehdr->e32.e_shoff); 96 } 97 98 #define EHDR_HALF(fn_name) \ 99 static uint16_t ehdr64_##fn_name(Elf_Ehdr *ehdr) \ 100 { \ 101 return r2(&ehdr->e64.e_##fn_name); \ 102 } \ 103 \ 104 static uint16_t ehdr32_##fn_name(Elf_Ehdr *ehdr) \ 105 { \ 106 return r2(&ehdr->e32.e_##fn_name); \ 107 } 108 109 EHDR_HALF(shentsize) 110 EHDR_HALF(shstrndx) 111 EHDR_HALF(shnum) 112 113 /* 114 * Get the whole file as a programming convenience in order to avoid 115 * malloc+lseek+read+free of many pieces. If successful, then mmap 116 * avoids copying unused pieces; else just read the whole file. 117 * Open for both read and write. 118 */ 119 static void *mmap_file(char const *fname, size_t *size) 120 { 121 int fd; 122 struct stat sb; 123 void *addr = NULL; 124 125 fd = open(fname, O_RDWR); 126 if (fd < 0) { 127 perror(fname); 128 return NULL; 129 } 130 if (fstat(fd, &sb) < 0) { 131 perror(fname); 132 goto out; 133 } 134 if (!S_ISREG(sb.st_mode)) { 135 fprintf(stderr, "not a regular file: %s\n", fname); 136 goto out; 137 } 138 139 addr = mmap(0, sb.st_size, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0); 140 if (addr == MAP_FAILED) { 141 fprintf(stderr, "Could not mmap file: %s\n", fname); 142 goto out; 143 } 144 145 *size = sb.st_size; 146 147 out: 148 close(fd); 149 return addr; 150 } 151 152 static uint32_t rbe(const uint32_t *x) 153 { 154 return get_unaligned_be32(x); 155 } 156 157 static uint16_t r2be(const uint16_t *x) 158 { 159 return get_unaligned_be16(x); 160 } 161 162 static uint64_t r8be(const uint64_t *x) 163 { 164 return get_unaligned_be64(x); 165 } 166 167 static uint32_t rle(const uint32_t *x) 168 { 169 return get_unaligned_le32(x); 170 } 171 172 static uint16_t r2le(const uint16_t *x) 173 { 174 return get_unaligned_le16(x); 175 } 176 177 static uint64_t r8le(const uint64_t *x) 178 { 179 return get_unaligned_le64(x); 180 } 181 182 static void wbe(uint32_t val, uint32_t *x) 183 { 184 put_unaligned_be32(val, x); 185 } 186 187 static void wle(uint32_t val, uint32_t *x) 188 { 189 put_unaligned_le32(val, x); 190 } 191 192 /* 193 * Move reserved section indices SHN_LORESERVE..SHN_HIRESERVE out of 194 * the way to -256..-1, to avoid conflicting with real section 195 * indices. 196 */ 197 #define SPECIAL(i) ((i) - (SHN_HIRESERVE + 1)) 198 199 static inline int is_shndx_special(unsigned int i) 200 { 201 return i != SHN_XINDEX && i >= SHN_LORESERVE && i <= SHN_HIRESERVE; 202 } 203 204 /* Accessor for sym->st_shndx, hides ugliness of "64k sections" */ 205 static inline unsigned int get_secindex(unsigned int shndx, 206 unsigned int sym_offs, 207 const Elf32_Word *symtab_shndx_start) 208 { 209 if (is_shndx_special(shndx)) 210 return SPECIAL(shndx); 211 if (shndx != SHN_XINDEX) 212 return shndx; 213 return r(&symtab_shndx_start[sym_offs]); 214 } 215 216 static int compare_extable_32(const void *a, const void *b) 217 { 218 Elf32_Addr av = r(a); 219 Elf32_Addr bv = r(b); 220 221 if (av < bv) 222 return -1; 223 return av > bv; 224 } 225 226 static int compare_extable_64(const void *a, const void *b) 227 { 228 Elf64_Addr av = r8(a); 229 Elf64_Addr bv = r8(b); 230 231 if (av < bv) 232 return -1; 233 return av > bv; 234 } 235 236 static inline void *get_index(void *start, int entsize, int index) 237 { 238 return start + (entsize * index); 239 } 240 241 /* 32 bit and 64 bit are very similar */ 242 #include "sorttable.h" 243 #define SORTTABLE_64 244 #include "sorttable.h" 245 246 static int compare_relative_table(const void *a, const void *b) 247 { 248 int32_t av = (int32_t)r(a); 249 int32_t bv = (int32_t)r(b); 250 251 if (av < bv) 252 return -1; 253 if (av > bv) 254 return 1; 255 return 0; 256 } 257 258 static void sort_relative_table(char *extab_image, int image_size) 259 { 260 int i = 0; 261 262 /* 263 * Do the same thing the runtime sort does, first normalize to 264 * being relative to the start of the section. 265 */ 266 while (i < image_size) { 267 uint32_t *loc = (uint32_t *)(extab_image + i); 268 w(r(loc) + i, loc); 269 i += 4; 270 } 271 272 qsort(extab_image, image_size / 8, 8, compare_relative_table); 273 274 /* Now denormalize. */ 275 i = 0; 276 while (i < image_size) { 277 uint32_t *loc = (uint32_t *)(extab_image + i); 278 w(r(loc) - i, loc); 279 i += 4; 280 } 281 } 282 283 static void sort_relative_table_with_data(char *extab_image, int image_size) 284 { 285 int i = 0; 286 287 while (i < image_size) { 288 uint32_t *loc = (uint32_t *)(extab_image + i); 289 290 w(r(loc) + i, loc); 291 w(r(loc + 1) + i + 4, loc + 1); 292 /* Don't touch the fixup type or data */ 293 294 i += sizeof(uint32_t) * 3; 295 } 296 297 qsort(extab_image, image_size / 12, 12, compare_relative_table); 298 299 i = 0; 300 while (i < image_size) { 301 uint32_t *loc = (uint32_t *)(extab_image + i); 302 303 w(r(loc) - i, loc); 304 w(r(loc + 1) - (i + 4), loc + 1); 305 /* Don't touch the fixup type or data */ 306 307 i += sizeof(uint32_t) * 3; 308 } 309 } 310 311 static int do_file(char const *const fname, void *addr) 312 { 313 int rc = -1; 314 Elf_Ehdr *ehdr = addr; 315 table_sort_t custom_sort = NULL; 316 317 switch (ehdr->e32.e_ident[EI_DATA]) { 318 case ELFDATA2LSB: 319 r = rle; 320 r2 = r2le; 321 r8 = r8le; 322 w = wle; 323 break; 324 case ELFDATA2MSB: 325 r = rbe; 326 r2 = r2be; 327 r8 = r8be; 328 w = wbe; 329 break; 330 default: 331 fprintf(stderr, "unrecognized ELF data encoding %d: %s\n", 332 ehdr->e32.e_ident[EI_DATA], fname); 333 return -1; 334 } 335 336 if (memcmp(ELFMAG, ehdr->e32.e_ident, SELFMAG) != 0 || 337 (r2(&ehdr->e32.e_type) != ET_EXEC && r2(&ehdr->e32.e_type) != ET_DYN) || 338 ehdr->e32.e_ident[EI_VERSION] != EV_CURRENT) { 339 fprintf(stderr, "unrecognized ET_EXEC/ET_DYN file %s\n", fname); 340 return -1; 341 } 342 343 switch (r2(&ehdr->e32.e_machine)) { 344 case EM_386: 345 case EM_AARCH64: 346 case EM_LOONGARCH: 347 case EM_RISCV: 348 case EM_S390: 349 case EM_X86_64: 350 custom_sort = sort_relative_table_with_data; 351 break; 352 case EM_PARISC: 353 case EM_PPC: 354 case EM_PPC64: 355 custom_sort = sort_relative_table; 356 break; 357 case EM_ARCOMPACT: 358 case EM_ARCV2: 359 case EM_ARM: 360 case EM_MICROBLAZE: 361 case EM_MIPS: 362 case EM_XTENSA: 363 break; 364 default: 365 fprintf(stderr, "unrecognized e_machine %d %s\n", 366 r2(&ehdr->e32.e_machine), fname); 367 return -1; 368 } 369 370 switch (ehdr->e32.e_ident[EI_CLASS]) { 371 case ELFCLASS32: 372 if (r2(&ehdr->e32.e_ehsize) != sizeof(Elf32_Ehdr) || 373 r2(&ehdr->e32.e_shentsize) != sizeof(Elf32_Shdr)) { 374 fprintf(stderr, 375 "unrecognized ET_EXEC/ET_DYN file: %s\n", fname); 376 break; 377 } 378 rc = do_sort_32(ehdr, fname, custom_sort); 379 break; 380 case ELFCLASS64: 381 { 382 if (r2(&ehdr->e64.e_ehsize) != sizeof(Elf64_Ehdr) || 383 r2(&ehdr->e64.e_shentsize) != sizeof(Elf64_Shdr)) { 384 fprintf(stderr, 385 "unrecognized ET_EXEC/ET_DYN file: %s\n", 386 fname); 387 break; 388 } 389 rc = do_sort_64(ehdr, fname, custom_sort); 390 } 391 break; 392 default: 393 fprintf(stderr, "unrecognized ELF class %d %s\n", 394 ehdr->e32.e_ident[EI_CLASS], fname); 395 break; 396 } 397 398 return rc; 399 } 400 401 int main(int argc, char *argv[]) 402 { 403 int i, n_error = 0; /* gcc-4.3.0 false positive complaint */ 404 size_t size = 0; 405 void *addr = NULL; 406 407 if (argc < 2) { 408 fprintf(stderr, "usage: sorttable vmlinux...\n"); 409 return 0; 410 } 411 412 /* Process each file in turn, allowing deep failure. */ 413 for (i = 1; i < argc; i++) { 414 addr = mmap_file(argv[i], &size); 415 if (!addr) { 416 ++n_error; 417 continue; 418 } 419 420 if (do_file(argv[i], addr)) 421 ++n_error; 422 423 munmap(addr, size); 424 } 425 426 return !!n_error; 427 } 428