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 #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 static void (*w2)(uint16_t, uint16_t *); 72 static void (*w8)(uint64_t, uint64_t *); 73 typedef void (*table_sort_t)(char *, int); 74 75 /* 76 * Get the whole file as a programming convenience in order to avoid 77 * malloc+lseek+read+free of many pieces. If successful, then mmap 78 * avoids copying unused pieces; else just read the whole file. 79 * Open for both read and write. 80 */ 81 static void *mmap_file(char const *fname, size_t *size) 82 { 83 int fd; 84 struct stat sb; 85 void *addr = NULL; 86 87 fd = open(fname, O_RDWR); 88 if (fd < 0) { 89 perror(fname); 90 return NULL; 91 } 92 if (fstat(fd, &sb) < 0) { 93 perror(fname); 94 goto out; 95 } 96 if (!S_ISREG(sb.st_mode)) { 97 fprintf(stderr, "not a regular file: %s\n", fname); 98 goto out; 99 } 100 101 addr = mmap(0, sb.st_size, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0); 102 if (addr == MAP_FAILED) { 103 fprintf(stderr, "Could not mmap file: %s\n", fname); 104 goto out; 105 } 106 107 *size = sb.st_size; 108 109 out: 110 close(fd); 111 return addr; 112 } 113 114 static uint32_t rbe(const uint32_t *x) 115 { 116 return get_unaligned_be32(x); 117 } 118 119 static uint16_t r2be(const uint16_t *x) 120 { 121 return get_unaligned_be16(x); 122 } 123 124 static uint64_t r8be(const uint64_t *x) 125 { 126 return get_unaligned_be64(x); 127 } 128 129 static uint32_t rle(const uint32_t *x) 130 { 131 return get_unaligned_le32(x); 132 } 133 134 static uint16_t r2le(const uint16_t *x) 135 { 136 return get_unaligned_le16(x); 137 } 138 139 static uint64_t r8le(const uint64_t *x) 140 { 141 return get_unaligned_le64(x); 142 } 143 144 static void wbe(uint32_t val, uint32_t *x) 145 { 146 put_unaligned_be32(val, x); 147 } 148 149 static void w2be(uint16_t val, uint16_t *x) 150 { 151 put_unaligned_be16(val, x); 152 } 153 154 static void w8be(uint64_t val, uint64_t *x) 155 { 156 put_unaligned_be64(val, x); 157 } 158 159 static void wle(uint32_t val, uint32_t *x) 160 { 161 put_unaligned_le32(val, x); 162 } 163 164 static void w2le(uint16_t val, uint16_t *x) 165 { 166 put_unaligned_le16(val, x); 167 } 168 169 static void w8le(uint64_t val, uint64_t *x) 170 { 171 put_unaligned_le64(val, x); 172 } 173 174 /* 175 * Move reserved section indices SHN_LORESERVE..SHN_HIRESERVE out of 176 * the way to -256..-1, to avoid conflicting with real section 177 * indices. 178 */ 179 #define SPECIAL(i) ((i) - (SHN_HIRESERVE + 1)) 180 181 static inline int is_shndx_special(unsigned int i) 182 { 183 return i != SHN_XINDEX && i >= SHN_LORESERVE && i <= SHN_HIRESERVE; 184 } 185 186 /* Accessor for sym->st_shndx, hides ugliness of "64k sections" */ 187 static inline unsigned int get_secindex(unsigned int shndx, 188 unsigned int sym_offs, 189 const Elf32_Word *symtab_shndx_start) 190 { 191 if (is_shndx_special(shndx)) 192 return SPECIAL(shndx); 193 if (shndx != SHN_XINDEX) 194 return shndx; 195 return r(&symtab_shndx_start[sym_offs]); 196 } 197 198 /* 32 bit and 64 bit are very similar */ 199 #include "sorttable.h" 200 #define SORTTABLE_64 201 #include "sorttable.h" 202 203 static int compare_relative_table(const void *a, const void *b) 204 { 205 int32_t av = (int32_t)r(a); 206 int32_t bv = (int32_t)r(b); 207 208 if (av < bv) 209 return -1; 210 if (av > bv) 211 return 1; 212 return 0; 213 } 214 215 static void sort_relative_table(char *extab_image, int image_size) 216 { 217 int i = 0; 218 219 /* 220 * Do the same thing the runtime sort does, first normalize to 221 * being relative to the start of the section. 222 */ 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 qsort(extab_image, image_size / 8, 8, compare_relative_table); 230 231 /* Now denormalize. */ 232 i = 0; 233 while (i < image_size) { 234 uint32_t *loc = (uint32_t *)(extab_image + i); 235 w(r(loc) - i, loc); 236 i += 4; 237 } 238 } 239 240 static void sort_relative_table_with_data(char *extab_image, int image_size) 241 { 242 int i = 0; 243 244 while (i < image_size) { 245 uint32_t *loc = (uint32_t *)(extab_image + i); 246 247 w(r(loc) + i, loc); 248 w(r(loc + 1) + i + 4, loc + 1); 249 /* Don't touch the fixup type or data */ 250 251 i += sizeof(uint32_t) * 3; 252 } 253 254 qsort(extab_image, image_size / 12, 12, compare_relative_table); 255 256 i = 0; 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 } 267 268 static int do_file(char const *const fname, void *addr) 269 { 270 int rc = -1; 271 Elf32_Ehdr *ehdr = addr; 272 table_sort_t custom_sort = NULL; 273 274 switch (ehdr->e_ident[EI_DATA]) { 275 case ELFDATA2LSB: 276 r = rle; 277 r2 = r2le; 278 r8 = r8le; 279 w = wle; 280 w2 = w2le; 281 w8 = w8le; 282 break; 283 case ELFDATA2MSB: 284 r = rbe; 285 r2 = r2be; 286 r8 = r8be; 287 w = wbe; 288 w2 = w2be; 289 w8 = w8be; 290 break; 291 default: 292 fprintf(stderr, "unrecognized ELF data encoding %d: %s\n", 293 ehdr->e_ident[EI_DATA], fname); 294 return -1; 295 } 296 297 if (memcmp(ELFMAG, ehdr->e_ident, SELFMAG) != 0 || 298 (r2(&ehdr->e_type) != ET_EXEC && r2(&ehdr->e_type) != ET_DYN) || 299 ehdr->e_ident[EI_VERSION] != EV_CURRENT) { 300 fprintf(stderr, "unrecognized ET_EXEC/ET_DYN file %s\n", fname); 301 return -1; 302 } 303 304 switch (r2(&ehdr->e_machine)) { 305 case EM_386: 306 case EM_AARCH64: 307 case EM_LOONGARCH: 308 case EM_RISCV: 309 case EM_S390: 310 case EM_X86_64: 311 custom_sort = sort_relative_table_with_data; 312 break; 313 case EM_PARISC: 314 case EM_PPC: 315 case EM_PPC64: 316 custom_sort = sort_relative_table; 317 break; 318 case EM_ARCOMPACT: 319 case EM_ARCV2: 320 case EM_ARM: 321 case EM_MICROBLAZE: 322 case EM_MIPS: 323 case EM_XTENSA: 324 break; 325 default: 326 fprintf(stderr, "unrecognized e_machine %d %s\n", 327 r2(&ehdr->e_machine), fname); 328 return -1; 329 } 330 331 switch (ehdr->e_ident[EI_CLASS]) { 332 case ELFCLASS32: 333 if (r2(&ehdr->e_ehsize) != sizeof(Elf32_Ehdr) || 334 r2(&ehdr->e_shentsize) != sizeof(Elf32_Shdr)) { 335 fprintf(stderr, 336 "unrecognized ET_EXEC/ET_DYN file: %s\n", fname); 337 break; 338 } 339 rc = do_sort_32(ehdr, fname, custom_sort); 340 break; 341 case ELFCLASS64: 342 { 343 Elf64_Ehdr *const ghdr = (Elf64_Ehdr *)ehdr; 344 if (r2(&ghdr->e_ehsize) != sizeof(Elf64_Ehdr) || 345 r2(&ghdr->e_shentsize) != sizeof(Elf64_Shdr)) { 346 fprintf(stderr, 347 "unrecognized ET_EXEC/ET_DYN file: %s\n", 348 fname); 349 break; 350 } 351 rc = do_sort_64(ghdr, fname, custom_sort); 352 } 353 break; 354 default: 355 fprintf(stderr, "unrecognized ELF class %d %s\n", 356 ehdr->e_ident[EI_CLASS], fname); 357 break; 358 } 359 360 return rc; 361 } 362 363 int main(int argc, char *argv[]) 364 { 365 int i, n_error = 0; /* gcc-4.3.0 false positive complaint */ 366 size_t size = 0; 367 void *addr = NULL; 368 369 if (argc < 2) { 370 fprintf(stderr, "usage: sorttable vmlinux...\n"); 371 return 0; 372 } 373 374 /* Process each file in turn, allowing deep failure. */ 375 for (i = 1; i < argc; i++) { 376 addr = mmap_file(argv[i], &size); 377 if (!addr) { 378 ++n_error; 379 continue; 380 } 381 382 if (do_file(argv[i], addr)) 383 ++n_error; 384 385 munmap(addr, size); 386 } 387 388 return !!n_error; 389 } 390