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 static uint32_t (*r)(const uint32_t *); 58 static uint16_t (*r2)(const uint16_t *); 59 static uint64_t (*r8)(const uint64_t *); 60 static void (*w)(uint32_t, uint32_t *); 61 static void (*w2)(uint16_t, uint16_t *); 62 static void (*w8)(uint64_t, uint64_t *); 63 typedef void (*table_sort_t)(char *, int); 64 65 /* 66 * Get the whole file as a programming convenience in order to avoid 67 * malloc+lseek+read+free of many pieces. If successful, then mmap 68 * avoids copying unused pieces; else just read the whole file. 69 * Open for both read and write. 70 */ 71 static void *mmap_file(char const *fname, size_t *size) 72 { 73 int fd; 74 struct stat sb; 75 void *addr = NULL; 76 77 fd = open(fname, O_RDWR); 78 if (fd < 0) { 79 perror(fname); 80 return NULL; 81 } 82 if (fstat(fd, &sb) < 0) { 83 perror(fname); 84 goto out; 85 } 86 if (!S_ISREG(sb.st_mode)) { 87 fprintf(stderr, "not a regular file: %s\n", fname); 88 goto out; 89 } 90 91 addr = mmap(0, sb.st_size, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0); 92 if (addr == MAP_FAILED) { 93 fprintf(stderr, "Could not mmap file: %s\n", fname); 94 goto out; 95 } 96 97 *size = sb.st_size; 98 99 out: 100 close(fd); 101 return addr; 102 } 103 104 static uint32_t rbe(const uint32_t *x) 105 { 106 return get_unaligned_be32(x); 107 } 108 109 static uint16_t r2be(const uint16_t *x) 110 { 111 return get_unaligned_be16(x); 112 } 113 114 static uint64_t r8be(const uint64_t *x) 115 { 116 return get_unaligned_be64(x); 117 } 118 119 static uint32_t rle(const uint32_t *x) 120 { 121 return get_unaligned_le32(x); 122 } 123 124 static uint16_t r2le(const uint16_t *x) 125 { 126 return get_unaligned_le16(x); 127 } 128 129 static uint64_t r8le(const uint64_t *x) 130 { 131 return get_unaligned_le64(x); 132 } 133 134 static void wbe(uint32_t val, uint32_t *x) 135 { 136 put_unaligned_be32(val, x); 137 } 138 139 static void w2be(uint16_t val, uint16_t *x) 140 { 141 put_unaligned_be16(val, x); 142 } 143 144 static void w8be(uint64_t val, uint64_t *x) 145 { 146 put_unaligned_be64(val, x); 147 } 148 149 static void wle(uint32_t val, uint32_t *x) 150 { 151 put_unaligned_le32(val, x); 152 } 153 154 static void w2le(uint16_t val, uint16_t *x) 155 { 156 put_unaligned_le16(val, x); 157 } 158 159 static void w8le(uint64_t val, uint64_t *x) 160 { 161 put_unaligned_le64(val, x); 162 } 163 164 /* 165 * Move reserved section indices SHN_LORESERVE..SHN_HIRESERVE out of 166 * the way to -256..-1, to avoid conflicting with real section 167 * indices. 168 */ 169 #define SPECIAL(i) ((i) - (SHN_HIRESERVE + 1)) 170 171 static inline int is_shndx_special(unsigned int i) 172 { 173 return i != SHN_XINDEX && i >= SHN_LORESERVE && i <= SHN_HIRESERVE; 174 } 175 176 /* Accessor for sym->st_shndx, hides ugliness of "64k sections" */ 177 static inline unsigned int get_secindex(unsigned int shndx, 178 unsigned int sym_offs, 179 const Elf32_Word *symtab_shndx_start) 180 { 181 if (is_shndx_special(shndx)) 182 return SPECIAL(shndx); 183 if (shndx != SHN_XINDEX) 184 return shndx; 185 return r(&symtab_shndx_start[sym_offs]); 186 } 187 188 /* 32 bit and 64 bit are very similar */ 189 #include "sorttable.h" 190 #define SORTTABLE_64 191 #include "sorttable.h" 192 193 static int compare_relative_table(const void *a, const void *b) 194 { 195 int32_t av = (int32_t)r(a); 196 int32_t bv = (int32_t)r(b); 197 198 if (av < bv) 199 return -1; 200 if (av > bv) 201 return 1; 202 return 0; 203 } 204 205 static void sort_relative_table(char *extab_image, int image_size) 206 { 207 int i = 0; 208 209 /* 210 * Do the same thing the runtime sort does, first normalize to 211 * being relative to the start of the section. 212 */ 213 while (i < image_size) { 214 uint32_t *loc = (uint32_t *)(extab_image + i); 215 w(r(loc) + i, loc); 216 i += 4; 217 } 218 219 qsort(extab_image, image_size / 8, 8, compare_relative_table); 220 221 /* Now denormalize. */ 222 i = 0; 223 while (i < image_size) { 224 uint32_t *loc = (uint32_t *)(extab_image + i); 225 w(r(loc) - i, loc); 226 i += 4; 227 } 228 } 229 230 static void x86_sort_relative_table(char *extab_image, int image_size) 231 { 232 int i = 0; 233 234 while (i < image_size) { 235 uint32_t *loc = (uint32_t *)(extab_image + i); 236 237 w(r(loc) + i, loc); 238 w(r(loc + 1) + i + 4, loc + 1); 239 w(r(loc + 2) + i + 8, loc + 2); 240 241 i += sizeof(uint32_t) * 3; 242 } 243 244 qsort(extab_image, image_size / 12, 12, compare_relative_table); 245 246 i = 0; 247 while (i < image_size) { 248 uint32_t *loc = (uint32_t *)(extab_image + i); 249 250 w(r(loc) - i, loc); 251 w(r(loc + 1) - (i + 4), loc + 1); 252 w(r(loc + 2) - (i + 8), loc + 2); 253 254 i += sizeof(uint32_t) * 3; 255 } 256 } 257 258 static void s390_sort_relative_table(char *extab_image, int image_size) 259 { 260 int i; 261 262 for (i = 0; i < image_size; i += 16) { 263 char *loc = extab_image + i; 264 uint64_t handler; 265 266 w(r((uint32_t *)loc) + i, (uint32_t *)loc); 267 w(r((uint32_t *)(loc + 4)) + (i + 4), (uint32_t *)(loc + 4)); 268 /* 269 * 0 is a special self-relative handler value, which means that 270 * handler should be ignored. It is safe, because it means that 271 * handler field points to itself, which should never happen. 272 * When creating extable-relative values, keep it as 0, since 273 * this should never occur either: it would mean that handler 274 * field points to the first extable entry. 275 */ 276 handler = r8((uint64_t *)(loc + 8)); 277 if (handler) 278 handler += i + 8; 279 w8(handler, (uint64_t *)(loc + 8)); 280 } 281 282 qsort(extab_image, image_size / 16, 16, compare_relative_table); 283 284 for (i = 0; i < image_size; i += 16) { 285 char *loc = extab_image + i; 286 uint64_t handler; 287 288 w(r((uint32_t *)loc) - i, (uint32_t *)loc); 289 w(r((uint32_t *)(loc + 4)) - (i + 4), (uint32_t *)(loc + 4)); 290 handler = r8((uint64_t *)(loc + 8)); 291 if (handler) 292 handler -= i + 8; 293 w8(handler, (uint64_t *)(loc + 8)); 294 } 295 } 296 297 static int do_file(char const *const fname, void *addr) 298 { 299 int rc = -1; 300 Elf32_Ehdr *ehdr = addr; 301 table_sort_t custom_sort = NULL; 302 303 switch (ehdr->e_ident[EI_DATA]) { 304 case ELFDATA2LSB: 305 r = rle; 306 r2 = r2le; 307 r8 = r8le; 308 w = wle; 309 w2 = w2le; 310 w8 = w8le; 311 break; 312 case ELFDATA2MSB: 313 r = rbe; 314 r2 = r2be; 315 r8 = r8be; 316 w = wbe; 317 w2 = w2be; 318 w8 = w8be; 319 break; 320 default: 321 fprintf(stderr, "unrecognized ELF data encoding %d: %s\n", 322 ehdr->e_ident[EI_DATA], fname); 323 return -1; 324 } 325 326 if (memcmp(ELFMAG, ehdr->e_ident, SELFMAG) != 0 || 327 (r2(&ehdr->e_type) != ET_EXEC && r2(&ehdr->e_type) != ET_DYN) || 328 ehdr->e_ident[EI_VERSION] != EV_CURRENT) { 329 fprintf(stderr, "unrecognized ET_EXEC/ET_DYN file %s\n", fname); 330 return -1; 331 } 332 333 switch (r2(&ehdr->e_machine)) { 334 case EM_386: 335 case EM_X86_64: 336 custom_sort = x86_sort_relative_table; 337 break; 338 case EM_S390: 339 custom_sort = s390_sort_relative_table; 340 break; 341 case EM_AARCH64: 342 case EM_PARISC: 343 case EM_PPC: 344 case EM_PPC64: 345 custom_sort = sort_relative_table; 346 break; 347 case EM_ARCOMPACT: 348 case EM_ARCV2: 349 case EM_ARM: 350 case EM_MICROBLAZE: 351 case EM_MIPS: 352 case EM_RISCV: 353 case EM_XTENSA: 354 break; 355 default: 356 fprintf(stderr, "unrecognized e_machine %d %s\n", 357 r2(&ehdr->e_machine), fname); 358 return -1; 359 } 360 361 switch (ehdr->e_ident[EI_CLASS]) { 362 case ELFCLASS32: 363 if (r2(&ehdr->e_ehsize) != sizeof(Elf32_Ehdr) || 364 r2(&ehdr->e_shentsize) != sizeof(Elf32_Shdr)) { 365 fprintf(stderr, 366 "unrecognized ET_EXEC/ET_DYN file: %s\n", fname); 367 break; 368 } 369 rc = do_sort_32(ehdr, fname, custom_sort); 370 break; 371 case ELFCLASS64: 372 { 373 Elf64_Ehdr *const ghdr = (Elf64_Ehdr *)ehdr; 374 if (r2(&ghdr->e_ehsize) != sizeof(Elf64_Ehdr) || 375 r2(&ghdr->e_shentsize) != sizeof(Elf64_Shdr)) { 376 fprintf(stderr, 377 "unrecognized ET_EXEC/ET_DYN file: %s\n", 378 fname); 379 break; 380 } 381 rc = do_sort_64(ghdr, fname, custom_sort); 382 } 383 break; 384 default: 385 fprintf(stderr, "unrecognized ELF class %d %s\n", 386 ehdr->e_ident[EI_CLASS], fname); 387 break; 388 } 389 390 return rc; 391 } 392 393 int main(int argc, char *argv[]) 394 { 395 int i, n_error = 0; /* gcc-4.3.0 false positive complaint */ 396 size_t size = 0; 397 void *addr = NULL; 398 399 if (argc < 2) { 400 fprintf(stderr, "usage: sorttable vmlinux...\n"); 401 return 0; 402 } 403 404 /* Process each file in turn, allowing deep failure. */ 405 for (i = 1; i < argc; i++) { 406 addr = mmap_file(argv[i], &size); 407 if (!addr) { 408 ++n_error; 409 continue; 410 } 411 412 if (do_file(argv[i], addr)) 413 ++n_error; 414 415 munmap(addr, size); 416 } 417 418 return !!n_error; 419 } 420