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