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 /* 32 bit and 64 bit are very similar */ 177 #include "sorttable.h" 178 #define SORTTABLE_64 179 #include "sorttable.h" 180 181 static int compare_relative_table(const void *a, const void *b) 182 { 183 int32_t av = (int32_t)r(a); 184 int32_t bv = (int32_t)r(b); 185 186 if (av < bv) 187 return -1; 188 if (av > bv) 189 return 1; 190 return 0; 191 } 192 193 static void sort_relative_table(char *extab_image, int image_size) 194 { 195 int i = 0; 196 197 /* 198 * Do the same thing the runtime sort does, first normalize to 199 * being relative to the start of the section. 200 */ 201 while (i < image_size) { 202 uint32_t *loc = (uint32_t *)(extab_image + i); 203 w(r(loc) + i, loc); 204 i += 4; 205 } 206 207 qsort(extab_image, image_size / 8, 8, compare_relative_table); 208 209 /* Now denormalize. */ 210 i = 0; 211 while (i < image_size) { 212 uint32_t *loc = (uint32_t *)(extab_image + i); 213 w(r(loc) - i, loc); 214 i += 4; 215 } 216 } 217 218 static void sort_relative_table_with_data(char *extab_image, int image_size) 219 { 220 int i = 0; 221 222 while (i < image_size) { 223 uint32_t *loc = (uint32_t *)(extab_image + i); 224 225 w(r(loc) + i, loc); 226 w(r(loc + 1) + i + 4, loc + 1); 227 /* Don't touch the fixup type or data */ 228 229 i += sizeof(uint32_t) * 3; 230 } 231 232 qsort(extab_image, image_size / 12, 12, compare_relative_table); 233 234 i = 0; 235 while (i < image_size) { 236 uint32_t *loc = (uint32_t *)(extab_image + i); 237 238 w(r(loc) - i, loc); 239 w(r(loc + 1) - (i + 4), loc + 1); 240 /* Don't touch the fixup type or data */ 241 242 i += sizeof(uint32_t) * 3; 243 } 244 } 245 246 static int do_file(char const *const fname, void *addr) 247 { 248 int rc = -1; 249 Elf32_Ehdr *ehdr = addr; 250 table_sort_t custom_sort = NULL; 251 252 switch (ehdr->e_ident[EI_DATA]) { 253 case ELFDATA2LSB: 254 r = rle; 255 r2 = r2le; 256 r8 = r8le; 257 w = wle; 258 break; 259 case ELFDATA2MSB: 260 r = rbe; 261 r2 = r2be; 262 r8 = r8be; 263 w = wbe; 264 break; 265 default: 266 fprintf(stderr, "unrecognized ELF data encoding %d: %s\n", 267 ehdr->e_ident[EI_DATA], fname); 268 return -1; 269 } 270 271 if (memcmp(ELFMAG, ehdr->e_ident, SELFMAG) != 0 || 272 (r2(&ehdr->e_type) != ET_EXEC && r2(&ehdr->e_type) != ET_DYN) || 273 ehdr->e_ident[EI_VERSION] != EV_CURRENT) { 274 fprintf(stderr, "unrecognized ET_EXEC/ET_DYN file %s\n", fname); 275 return -1; 276 } 277 278 switch (r2(&ehdr->e_machine)) { 279 case EM_386: 280 case EM_AARCH64: 281 case EM_LOONGARCH: 282 case EM_RISCV: 283 case EM_S390: 284 case EM_X86_64: 285 custom_sort = sort_relative_table_with_data; 286 break; 287 case EM_PARISC: 288 case EM_PPC: 289 case EM_PPC64: 290 custom_sort = sort_relative_table; 291 break; 292 case EM_ARCOMPACT: 293 case EM_ARCV2: 294 case EM_ARM: 295 case EM_MICROBLAZE: 296 case EM_MIPS: 297 case EM_XTENSA: 298 break; 299 default: 300 fprintf(stderr, "unrecognized e_machine %d %s\n", 301 r2(&ehdr->e_machine), fname); 302 return -1; 303 } 304 305 switch (ehdr->e_ident[EI_CLASS]) { 306 case ELFCLASS32: 307 if (r2(&ehdr->e_ehsize) != sizeof(Elf32_Ehdr) || 308 r2(&ehdr->e_shentsize) != sizeof(Elf32_Shdr)) { 309 fprintf(stderr, 310 "unrecognized ET_EXEC/ET_DYN file: %s\n", fname); 311 break; 312 } 313 rc = do_sort_32(ehdr, fname, custom_sort); 314 break; 315 case ELFCLASS64: 316 { 317 Elf64_Ehdr *const ghdr = (Elf64_Ehdr *)ehdr; 318 if (r2(&ghdr->e_ehsize) != sizeof(Elf64_Ehdr) || 319 r2(&ghdr->e_shentsize) != sizeof(Elf64_Shdr)) { 320 fprintf(stderr, 321 "unrecognized ET_EXEC/ET_DYN file: %s\n", 322 fname); 323 break; 324 } 325 rc = do_sort_64(ghdr, fname, custom_sort); 326 } 327 break; 328 default: 329 fprintf(stderr, "unrecognized ELF class %d %s\n", 330 ehdr->e_ident[EI_CLASS], fname); 331 break; 332 } 333 334 return rc; 335 } 336 337 int main(int argc, char *argv[]) 338 { 339 int i, n_error = 0; /* gcc-4.3.0 false positive complaint */ 340 size_t size = 0; 341 void *addr = NULL; 342 343 if (argc < 2) { 344 fprintf(stderr, "usage: sorttable vmlinux...\n"); 345 return 0; 346 } 347 348 /* Process each file in turn, allowing deep failure. */ 349 for (i = 1; i < argc; i++) { 350 addr = mmap_file(argv[i], &size); 351 if (!addr) { 352 ++n_error; 353 continue; 354 } 355 356 if (do_file(argv[i], addr)) 357 ++n_error; 358 359 munmap(addr, size); 360 } 361 362 return !!n_error; 363 } 364