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