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