Aaron Durbin | 4fde5a6 | 2014-03-07 15:11:53 -0600 | [diff] [blame] | 1 | /* |
Frans Hendriks | 166cbde | 2018-11-22 14:21:12 +0100 | [diff] [blame] | 2 | * Copyright (C) 2014 Google, Inc. |
| 3 | * Copyright (C) 2018 Eltan B.V. |
Aaron Durbin | 4fde5a6 | 2014-03-07 15:11:53 -0600 | [diff] [blame] | 4 | * |
| 5 | * This program is free software; you can redistribute it and/or modify |
| 6 | * it under the terms of the GNU General Public License as published by |
| 7 | * the Free Software Foundation; version 2 of the License. |
| 8 | * |
| 9 | * This program is distributed in the hope that it will be useful, |
| 10 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 11 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 12 | * GNU General Public License for more details. |
Aaron Durbin | 4fde5a6 | 2014-03-07 15:11:53 -0600 | [diff] [blame] | 13 | */ |
| 14 | |
Sol Boucher | 0e53931 | 2015-03-05 15:38:03 -0800 | [diff] [blame] | 15 | #include <inttypes.h> |
Aaron Durbin | 4fde5a6 | 2014-03-07 15:11:53 -0600 | [diff] [blame] | 16 | #include <stdio.h> |
| 17 | #include <stdlib.h> |
| 18 | #include <string.h> |
| 19 | |
| 20 | #include "elfparsing.h" |
| 21 | #include "rmodule.h" |
Aaron Durbin | dc9f5cd | 2015-09-08 13:34:43 -0500 | [diff] [blame] | 22 | #include <commonlib/rmodule-defs.h> |
Aaron Durbin | 4fde5a6 | 2014-03-07 15:11:53 -0600 | [diff] [blame] | 23 | |
Aaron Durbin | 4fde5a6 | 2014-03-07 15:11:53 -0600 | [diff] [blame] | 24 | /* |
| 25 | * Architecture specific support operations. |
| 26 | */ |
Sol Boucher | 0e53931 | 2015-03-05 15:38:03 -0800 | [diff] [blame] | 27 | static int valid_reloc_386(Elf64_Rela *rel) |
Aaron Durbin | 4fde5a6 | 2014-03-07 15:11:53 -0600 | [diff] [blame] | 28 | { |
| 29 | int type; |
| 30 | |
| 31 | type = ELF64_R_TYPE(rel->r_info); |
| 32 | |
| 33 | /* Only these 2 relocations are expected to be found. */ |
| 34 | return (type == R_386_32 || type == R_386_PC32); |
| 35 | } |
| 36 | |
Sol Boucher | 0e53931 | 2015-03-05 15:38:03 -0800 | [diff] [blame] | 37 | static int should_emit_386(Elf64_Rela *rel) |
Aaron Durbin | 4fde5a6 | 2014-03-07 15:11:53 -0600 | [diff] [blame] | 38 | { |
| 39 | int type; |
| 40 | |
| 41 | type = ELF64_R_TYPE(rel->r_info); |
| 42 | |
| 43 | /* R_386_32 relocations are absolute. Must emit these. */ |
| 44 | return (type == R_386_32); |
| 45 | } |
| 46 | |
Patrick Rudolph | 565bebe | 2018-11-26 15:54:21 +0100 | [diff] [blame] | 47 | static int valid_reloc_amd64(Elf64_Rela *rel) |
| 48 | { |
| 49 | int type; |
| 50 | |
| 51 | type = ELF64_R_TYPE(rel->r_info); |
| 52 | |
Patrick Rudolph | 44b4ec7 | 2019-02-15 14:41:20 +0100 | [diff] [blame] | 53 | /* Only these 6 relocations are expected to be found. */ |
Patrick Rudolph | 565bebe | 2018-11-26 15:54:21 +0100 | [diff] [blame] | 54 | return (type == R_AMD64_64 || |
| 55 | type == R_AMD64_PC64 || |
| 56 | type == R_AMD64_32S || |
| 57 | type == R_AMD64_32 || |
Patrick Rudolph | 44b4ec7 | 2019-02-15 14:41:20 +0100 | [diff] [blame] | 58 | type == R_AMD64_PC32 || |
| 59 | /* |
| 60 | * binutils 2.31 introduced R_AMD64_PLT32 for non local |
| 61 | * functions. As we don't care about procedure linkage |
| 62 | * table entries handle it as R_X86_64_PC32. |
| 63 | */ |
| 64 | type == R_AMD64_PLT32); |
Patrick Rudolph | 565bebe | 2018-11-26 15:54:21 +0100 | [diff] [blame] | 65 | } |
| 66 | |
| 67 | static int should_emit_amd64(Elf64_Rela *rel) |
| 68 | { |
| 69 | int type; |
| 70 | |
| 71 | type = ELF64_R_TYPE(rel->r_info); |
| 72 | |
| 73 | /* Only emit absolute relocations */ |
| 74 | return (type == R_AMD64_64 || |
Patrick Rudolph | 565bebe | 2018-11-26 15:54:21 +0100 | [diff] [blame] | 75 | type == R_AMD64_32S || |
| 76 | type == R_AMD64_32); |
| 77 | } |
| 78 | |
Sol Boucher | 0e53931 | 2015-03-05 15:38:03 -0800 | [diff] [blame] | 79 | static int valid_reloc_arm(Elf64_Rela *rel) |
Aaron Durbin | 785e47b | 2014-03-20 11:08:02 -0500 | [diff] [blame] | 80 | { |
| 81 | int type; |
| 82 | |
| 83 | type = ELF64_R_TYPE(rel->r_info); |
| 84 | |
Furquan Shaikh | c4f08f7 | 2014-07-23 13:42:22 -0700 | [diff] [blame] | 85 | /* Only these 6 relocations are expected to be found. */ |
Aaron Durbin | 785e47b | 2014-03-20 11:08:02 -0500 | [diff] [blame] | 86 | return (type == R_ARM_ABS32 || type == R_ARM_THM_PC22 || |
Furquan Shaikh | c4f08f7 | 2014-07-23 13:42:22 -0700 | [diff] [blame] | 87 | type == R_ARM_THM_JUMP24 || type == R_ARM_V4BX || |
| 88 | type == R_ARM_CALL || type == R_ARM_JUMP24); |
Aaron Durbin | 785e47b | 2014-03-20 11:08:02 -0500 | [diff] [blame] | 89 | } |
| 90 | |
Sol Boucher | 0e53931 | 2015-03-05 15:38:03 -0800 | [diff] [blame] | 91 | static int should_emit_arm(Elf64_Rela *rel) |
Aaron Durbin | 785e47b | 2014-03-20 11:08:02 -0500 | [diff] [blame] | 92 | { |
| 93 | int type; |
| 94 | |
| 95 | type = ELF64_R_TYPE(rel->r_info); |
| 96 | |
| 97 | /* R_ARM_ABS32 relocations are absolute. Must emit these. */ |
| 98 | return (type == R_ARM_ABS32); |
| 99 | } |
| 100 | |
Sol Boucher | 0e53931 | 2015-03-05 15:38:03 -0800 | [diff] [blame] | 101 | static int valid_reloc_aarch64(Elf64_Rela *rel) |
Furquan Shaikh | d2338ba | 2014-08-26 15:21:15 -0700 | [diff] [blame] | 102 | { |
| 103 | int type; |
| 104 | |
| 105 | type = ELF64_R_TYPE(rel->r_info); |
| 106 | |
| 107 | return (type == R_AARCH64_ADR_PREL_PG_HI21 || |
| 108 | type == R_AARCH64_ADD_ABS_LO12_NC || |
Furquan Shaikh | de77e6a | 2014-11-21 15:41:10 -0800 | [diff] [blame] | 109 | type == R_AARCH64_LDST8_ABS_LO12_NC || |
Furquan Shaikh | 16c0a41 | 2015-06-08 11:58:04 -0700 | [diff] [blame] | 110 | type == R_AARCH64_CONDBR19 || |
Furquan Shaikh | d2338ba | 2014-08-26 15:21:15 -0700 | [diff] [blame] | 111 | type == R_AARCH64_JUMP26 || |
| 112 | type == R_AARCH64_LDST32_ABS_LO12_NC || |
Aaron Durbin | a47898e | 2014-09-18 13:39:16 -0500 | [diff] [blame] | 113 | type == R_AARCH64_LDST64_ABS_LO12_NC || |
Furquan Shaikh | d2338ba | 2014-08-26 15:21:15 -0700 | [diff] [blame] | 114 | type == R_AARCH64_CALL26 || |
| 115 | type == R_AARCH64_ABS64 || |
| 116 | type == R_AARCH64_LD_PREL_LO19 || |
| 117 | type == R_AARCH64_ADR_PREL_LO21); |
| 118 | } |
| 119 | |
Sol Boucher | 0e53931 | 2015-03-05 15:38:03 -0800 | [diff] [blame] | 120 | static int should_emit_aarch64(Elf64_Rela *rel) |
Furquan Shaikh | d2338ba | 2014-08-26 15:21:15 -0700 | [diff] [blame] | 121 | { |
| 122 | int type; |
| 123 | |
| 124 | type = ELF64_R_TYPE(rel->r_info); |
| 125 | |
| 126 | return (type == R_AARCH64_ABS64); |
| 127 | } |
| 128 | |
Aaron Durbin | b39a974 | 2015-09-08 17:24:04 -0500 | [diff] [blame] | 129 | static const struct arch_ops reloc_ops[] = { |
Aaron Durbin | 4fde5a6 | 2014-03-07 15:11:53 -0600 | [diff] [blame] | 130 | { |
| 131 | .arch = EM_386, |
| 132 | .valid_type = valid_reloc_386, |
| 133 | .should_emit = should_emit_386, |
| 134 | }, |
Aaron Durbin | 785e47b | 2014-03-20 11:08:02 -0500 | [diff] [blame] | 135 | { |
Patrick Rudolph | 565bebe | 2018-11-26 15:54:21 +0100 | [diff] [blame] | 136 | .arch = EM_X86_64, |
| 137 | .valid_type = valid_reloc_amd64, |
| 138 | .should_emit = should_emit_amd64, |
| 139 | }, |
| 140 | { |
Aaron Durbin | 785e47b | 2014-03-20 11:08:02 -0500 | [diff] [blame] | 141 | .arch = EM_ARM, |
| 142 | .valid_type = valid_reloc_arm, |
| 143 | .should_emit = should_emit_arm, |
| 144 | }, |
Furquan Shaikh | d2338ba | 2014-08-26 15:21:15 -0700 | [diff] [blame] | 145 | { |
| 146 | .arch = EM_AARCH64, |
| 147 | .valid_type = valid_reloc_aarch64, |
| 148 | .should_emit = should_emit_aarch64, |
| 149 | }, |
Aaron Durbin | 4fde5a6 | 2014-03-07 15:11:53 -0600 | [diff] [blame] | 150 | }; |
| 151 | |
| 152 | /* |
| 153 | * Relocation processing loops. |
| 154 | */ |
| 155 | |
Aaron Durbin | b39a974 | 2015-09-08 17:24:04 -0500 | [diff] [blame] | 156 | static int for_each_reloc(struct rmod_context *ctx, struct reloc_filter *f, |
| 157 | int do_emit) |
Aaron Durbin | 4fde5a6 | 2014-03-07 15:11:53 -0600 | [diff] [blame] | 158 | { |
| 159 | Elf64_Half i; |
| 160 | struct parsed_elf *pelf = &ctx->pelf; |
| 161 | |
| 162 | for (i = 0; i < pelf->ehdr.e_shnum; i++) { |
| 163 | Elf64_Shdr *shdr; |
| 164 | Elf64_Rela *relocs; |
| 165 | Elf64_Xword nrelocs; |
| 166 | Elf64_Xword j; |
| 167 | |
| 168 | relocs = pelf->relocs[i]; |
| 169 | |
| 170 | /* No relocations in this section. */ |
| 171 | if (relocs == NULL) |
| 172 | continue; |
| 173 | |
| 174 | shdr = &pelf->shdr[i]; |
| 175 | nrelocs = shdr->sh_size / shdr->sh_entsize; |
| 176 | |
| 177 | for (j = 0; j < nrelocs; j++) { |
Aaron Durbin | b39a974 | 2015-09-08 17:24:04 -0500 | [diff] [blame] | 178 | int filter_emit = 1; |
Aaron Durbin | 4fde5a6 | 2014-03-07 15:11:53 -0600 | [diff] [blame] | 179 | Elf64_Rela *r = &relocs[j]; |
| 180 | |
Sol Boucher | 0e53931 | 2015-03-05 15:38:03 -0800 | [diff] [blame] | 181 | if (!ctx->ops->valid_type(r)) { |
Aaron Durbin | 4fde5a6 | 2014-03-07 15:11:53 -0600 | [diff] [blame] | 182 | ERROR("Invalid reloc type: %u\n", |
| 183 | (unsigned int)ELF64_R_TYPE(r->r_info)); |
| 184 | return -1; |
| 185 | } |
| 186 | |
Aaron Durbin | b39a974 | 2015-09-08 17:24:04 -0500 | [diff] [blame] | 187 | /* Allow the provided filter to have precedence. */ |
| 188 | if (f != NULL) { |
| 189 | filter_emit = f->filter(f, r); |
| 190 | |
| 191 | if (filter_emit < 0) |
| 192 | return filter_emit; |
| 193 | } |
| 194 | |
| 195 | if (filter_emit && ctx->ops->should_emit(r)) { |
Aaron Durbin | 4fde5a6 | 2014-03-07 15:11:53 -0600 | [diff] [blame] | 196 | int n = ctx->nrelocs; |
| 197 | if (do_emit) |
| 198 | ctx->emitted_relocs[n] = r->r_offset; |
| 199 | ctx->nrelocs++; |
| 200 | } |
| 201 | } |
| 202 | } |
| 203 | |
| 204 | return 0; |
| 205 | } |
| 206 | |
| 207 | static int find_program_segment(struct rmod_context *ctx) |
| 208 | { |
| 209 | int i; |
| 210 | int nsegments; |
| 211 | struct parsed_elf *pelf; |
Anatol Pomozov | 8cce701 | 2015-07-10 17:30:01 -0700 | [diff] [blame] | 212 | Elf64_Phdr *phdr = NULL; |
Aaron Durbin | 4fde5a6 | 2014-03-07 15:11:53 -0600 | [diff] [blame] | 213 | |
| 214 | pelf = &ctx->pelf; |
| 215 | |
| 216 | /* There should only be a single loadable segment. */ |
| 217 | nsegments = 0; |
| 218 | for (i = 0; i < pelf->ehdr.e_phnum; i++) { |
| 219 | if (pelf->phdr[i].p_type != PT_LOAD) |
| 220 | continue; |
| 221 | phdr = &pelf->phdr[i]; |
| 222 | nsegments++; |
| 223 | } |
| 224 | |
| 225 | if (nsegments != 1) { |
| 226 | ERROR("Unexepcted number of loadable segments: %d.\n", |
| 227 | nsegments); |
| 228 | return -1; |
| 229 | } |
| 230 | |
| 231 | INFO("Segment at 0x%0llx, file size 0x%0llx, mem size 0x%0llx.\n", |
| 232 | (long long)phdr->p_vaddr, (long long)phdr->p_filesz, |
| 233 | (long long)phdr->p_memsz); |
| 234 | |
| 235 | ctx->phdr = phdr; |
| 236 | |
| 237 | return 0; |
| 238 | } |
| 239 | |
| 240 | static int |
| 241 | filter_relocation_sections(struct rmod_context *ctx) |
| 242 | { |
| 243 | int i; |
| 244 | const char *shstrtab; |
| 245 | struct parsed_elf *pelf; |
| 246 | const Elf64_Phdr *phdr; |
| 247 | |
| 248 | pelf = &ctx->pelf; |
| 249 | phdr = ctx->phdr; |
| 250 | shstrtab = buffer_get(pelf->strtabs[pelf->ehdr.e_shstrndx]); |
| 251 | |
| 252 | /* |
| 253 | * Find all relocation sections that contain relocation entries |
| 254 | * for sections that fall within the bounds of the segment. For |
| 255 | * easier processing the pointer to the relocation array for the |
| 256 | * sections that don't fall within the loadable program are NULL'd |
| 257 | * out. |
| 258 | */ |
| 259 | for (i = 0; i < pelf->ehdr.e_shnum; i++) { |
| 260 | Elf64_Shdr *shdr; |
| 261 | Elf64_Word sh_info; |
| 262 | const char *section_name; |
| 263 | |
| 264 | shdr = &pelf->shdr[i]; |
| 265 | |
| 266 | /* Ignore non-relocation sections. */ |
| 267 | if (shdr->sh_type != SHT_RELA && shdr->sh_type != SHT_REL) |
| 268 | continue; |
| 269 | |
| 270 | /* Obtain section which relocations apply. */ |
| 271 | sh_info = shdr->sh_info; |
| 272 | shdr = &pelf->shdr[sh_info]; |
| 273 | |
| 274 | section_name = &shstrtab[shdr->sh_name]; |
| 275 | DEBUG("Relocation section found for '%s' section.\n", |
| 276 | section_name); |
| 277 | |
| 278 | /* Do not process relocations for debug sections. */ |
| 279 | if (strstr(section_name, ".debug") != NULL) { |
| 280 | pelf->relocs[i] = NULL; |
| 281 | continue; |
| 282 | } |
| 283 | |
| 284 | /* |
| 285 | * If relocations apply to a non program section ignore the |
| 286 | * relocations for future processing. |
| 287 | */ |
| 288 | if (shdr->sh_type != SHT_PROGBITS) { |
| 289 | pelf->relocs[i] = NULL; |
| 290 | continue; |
| 291 | } |
| 292 | |
| 293 | if (shdr->sh_addr < phdr->p_vaddr || |
| 294 | ((shdr->sh_addr + shdr->sh_size) > |
| 295 | (phdr->p_vaddr + phdr->p_memsz))) { |
| 296 | ERROR("Relocations being applied to section %d not " |
| 297 | "within segment region.\n", sh_info); |
| 298 | return -1; |
| 299 | } |
| 300 | } |
| 301 | |
| 302 | return 0; |
| 303 | } |
| 304 | |
| 305 | static int vaddr_cmp(const void *a, const void *b) |
| 306 | { |
| 307 | const Elf64_Addr *pa = a; |
| 308 | const Elf64_Addr *pb = b; |
| 309 | |
| 310 | if (*pa < *pb) |
| 311 | return -1; |
| 312 | if (*pa > *pb) |
| 313 | return 1; |
| 314 | return 0; |
| 315 | } |
| 316 | |
Aaron Durbin | b39a974 | 2015-09-08 17:24:04 -0500 | [diff] [blame] | 317 | int rmodule_collect_relocations(struct rmod_context *ctx, |
| 318 | struct reloc_filter *f) |
Aaron Durbin | 4fde5a6 | 2014-03-07 15:11:53 -0600 | [diff] [blame] | 319 | { |
Sol Boucher | 0e53931 | 2015-03-05 15:38:03 -0800 | [diff] [blame] | 320 | Elf64_Xword nrelocs; |
Aaron Durbin | 4fde5a6 | 2014-03-07 15:11:53 -0600 | [diff] [blame] | 321 | |
| 322 | /* |
| 323 | * The relocs array in the pelf should only contain relocations that |
| 324 | * apply to the program. Count the number relocations. Then collect |
| 325 | * them into the allocated buffer. |
| 326 | */ |
Aaron Durbin | b39a974 | 2015-09-08 17:24:04 -0500 | [diff] [blame] | 327 | if (for_each_reloc(ctx, f, 0)) |
Aaron Durbin | 4fde5a6 | 2014-03-07 15:11:53 -0600 | [diff] [blame] | 328 | return -1; |
| 329 | |
| 330 | nrelocs = ctx->nrelocs; |
Sol Boucher | 0e53931 | 2015-03-05 15:38:03 -0800 | [diff] [blame] | 331 | INFO("%" PRIu64 " relocations to be emitted.\n", nrelocs); |
Furquan Shaikh | b237c10 | 2014-08-26 14:59:36 -0700 | [diff] [blame] | 332 | if (!nrelocs) |
| 333 | return 0; |
Aaron Durbin | 4fde5a6 | 2014-03-07 15:11:53 -0600 | [diff] [blame] | 334 | |
| 335 | /* Reset the counter for indexing into the array. */ |
| 336 | ctx->nrelocs = 0; |
| 337 | ctx->emitted_relocs = calloc(nrelocs, sizeof(Elf64_Addr)); |
| 338 | /* Write out the relocations into the emitted_relocs array. */ |
Aaron Durbin | b39a974 | 2015-09-08 17:24:04 -0500 | [diff] [blame] | 339 | if (for_each_reloc(ctx, f, 1)) |
Aaron Durbin | 4fde5a6 | 2014-03-07 15:11:53 -0600 | [diff] [blame] | 340 | return -1; |
| 341 | |
| 342 | if (ctx->nrelocs != nrelocs) { |
| 343 | ERROR("Mismatch counted and emitted relocations: %zu vs %zu.\n", |
| 344 | (size_t)nrelocs, (size_t)ctx->nrelocs); |
| 345 | return -1; |
| 346 | } |
| 347 | |
| 348 | /* Sort the relocations by their address. */ |
| 349 | qsort(ctx->emitted_relocs, nrelocs, sizeof(Elf64_Addr), vaddr_cmp); |
| 350 | |
| 351 | return 0; |
| 352 | } |
| 353 | |
| 354 | static int |
| 355 | populate_sym(struct rmod_context *ctx, const char *sym_name, Elf64_Addr *addr, |
Aaron Durbin | c9b053d | 2015-09-06 10:39:10 -0500 | [diff] [blame] | 356 | int nsyms, const char *strtab, int optional) |
Aaron Durbin | 4fde5a6 | 2014-03-07 15:11:53 -0600 | [diff] [blame] | 357 | { |
| 358 | int i; |
| 359 | Elf64_Sym *syms; |
| 360 | |
| 361 | syms = ctx->pelf.syms; |
| 362 | |
| 363 | for (i = 0; i < nsyms; i++) { |
| 364 | if (syms[i].st_name == 0) |
| 365 | continue; |
| 366 | if (strcmp(sym_name, &strtab[syms[i].st_name])) |
| 367 | continue; |
| 368 | DEBUG("%s -> 0x%llx\n", sym_name, (long long)syms[i].st_value); |
| 369 | *addr = syms[i].st_value; |
| 370 | return 0; |
| 371 | } |
Aaron Durbin | c9b053d | 2015-09-06 10:39:10 -0500 | [diff] [blame] | 372 | |
| 373 | if (optional) { |
| 374 | DEBUG("optional symbol '%s' not found.\n", sym_name); |
| 375 | *addr = 0; |
| 376 | return 0; |
| 377 | } |
| 378 | |
Aaron Durbin | 4fde5a6 | 2014-03-07 15:11:53 -0600 | [diff] [blame] | 379 | ERROR("symbol '%s' not found.\n", sym_name); |
| 380 | return -1; |
| 381 | } |
| 382 | |
Aaron Durbin | 051a181 | 2015-09-08 15:52:01 -0500 | [diff] [blame] | 383 | static int populate_rmodule_info(struct rmod_context *ctx) |
Aaron Durbin | 4fde5a6 | 2014-03-07 15:11:53 -0600 | [diff] [blame] | 384 | { |
| 385 | int i; |
| 386 | const char *strtab; |
| 387 | struct parsed_elf *pelf; |
| 388 | Elf64_Ehdr *ehdr; |
| 389 | int nsyms; |
| 390 | |
| 391 | pelf = &ctx->pelf; |
| 392 | ehdr = &pelf->ehdr; |
| 393 | |
| 394 | /* Obtain the string table. */ |
| 395 | strtab = NULL; |
| 396 | for (i = 0; i < ehdr->e_shnum; i++) { |
| 397 | if (ctx->pelf.strtabs[i] == NULL) |
| 398 | continue; |
| 399 | /* Don't use the section headers' string table. */ |
| 400 | if (i == ehdr->e_shstrndx) |
| 401 | continue; |
| 402 | strtab = buffer_get(ctx->pelf.strtabs[i]); |
| 403 | break; |
| 404 | } |
| 405 | |
| 406 | if (strtab == NULL) { |
| 407 | ERROR("No string table found.\n"); |
| 408 | return -1; |
| 409 | } |
| 410 | |
| 411 | /* Determine number of symbols. */ |
| 412 | nsyms = 0; |
| 413 | for (i = 0; i < ehdr->e_shnum; i++) { |
| 414 | if (pelf->shdr[i].sh_type != SHT_SYMTAB) |
| 415 | continue; |
| 416 | |
| 417 | nsyms = pelf->shdr[i].sh_size / pelf->shdr[i].sh_entsize; |
| 418 | break; |
| 419 | } |
| 420 | |
Aaron Durbin | dde7629 | 2015-09-05 12:59:26 -0500 | [diff] [blame] | 421 | if (populate_sym(ctx, "_rmodule_params", &ctx->parameters_begin, |
Aaron Durbin | c9b053d | 2015-09-06 10:39:10 -0500 | [diff] [blame] | 422 | nsyms, strtab, 1)) |
Aaron Durbin | 4fde5a6 | 2014-03-07 15:11:53 -0600 | [diff] [blame] | 423 | return -1; |
| 424 | |
Aaron Durbin | dde7629 | 2015-09-05 12:59:26 -0500 | [diff] [blame] | 425 | if (populate_sym(ctx, "_ermodule_params", &ctx->parameters_end, |
Aaron Durbin | c9b053d | 2015-09-06 10:39:10 -0500 | [diff] [blame] | 426 | nsyms, strtab, 1)) |
Aaron Durbin | 4fde5a6 | 2014-03-07 15:11:53 -0600 | [diff] [blame] | 427 | return -1; |
| 428 | |
Aaron Durbin | c9b053d | 2015-09-06 10:39:10 -0500 | [diff] [blame] | 429 | if (populate_sym(ctx, "_bss", &ctx->bss_begin, nsyms, strtab, 0)) |
Aaron Durbin | 4fde5a6 | 2014-03-07 15:11:53 -0600 | [diff] [blame] | 430 | return -1; |
| 431 | |
Aaron Durbin | c9b053d | 2015-09-06 10:39:10 -0500 | [diff] [blame] | 432 | if (populate_sym(ctx, "_ebss", &ctx->bss_end, nsyms, strtab, 0)) |
Aaron Durbin | 4fde5a6 | 2014-03-07 15:11:53 -0600 | [diff] [blame] | 433 | return -1; |
| 434 | |
Aaron Durbin | 4fde5a6 | 2014-03-07 15:11:53 -0600 | [diff] [blame] | 435 | return 0; |
| 436 | } |
| 437 | |
| 438 | static int |
| 439 | add_section(struct elf_writer *ew, struct buffer *data, const char *name, |
| 440 | Elf64_Addr addr, Elf64_Word size) |
| 441 | { |
| 442 | Elf64_Shdr shdr; |
| 443 | int ret; |
| 444 | |
| 445 | memset(&shdr, 0, sizeof(shdr)); |
| 446 | if (data != NULL) { |
| 447 | shdr.sh_type = SHT_PROGBITS; |
| 448 | shdr.sh_flags = SHF_ALLOC | SHF_WRITE | SHF_EXECINSTR; |
| 449 | } else { |
| 450 | shdr.sh_type = SHT_NOBITS; |
| 451 | shdr.sh_flags = SHF_ALLOC; |
| 452 | } |
| 453 | shdr.sh_addr = addr; |
| 454 | shdr.sh_offset = addr; |
| 455 | shdr.sh_size = size; |
| 456 | |
| 457 | ret = elf_writer_add_section(ew, &shdr, data, name); |
| 458 | |
| 459 | if (ret) |
| 460 | ERROR("Could not add '%s' section.\n", name); |
| 461 | |
| 462 | return ret; |
| 463 | } |
| 464 | |
| 465 | static int |
| 466 | write_elf(const struct rmod_context *ctx, const struct buffer *in, |
| 467 | struct buffer *out) |
| 468 | { |
Aaron Durbin | 4fde5a6 | 2014-03-07 15:11:53 -0600 | [diff] [blame] | 469 | int ret; |
| 470 | int bit64; |
| 471 | size_t loc; |
| 472 | size_t rmod_data_size; |
| 473 | struct elf_writer *ew; |
| 474 | struct buffer rmod_data; |
| 475 | struct buffer rmod_header; |
| 476 | struct buffer program; |
| 477 | struct buffer relocs; |
| 478 | Elf64_Xword total_size; |
| 479 | Elf64_Addr addr; |
| 480 | Elf64_Ehdr ehdr; |
| 481 | |
| 482 | bit64 = ctx->pelf.ehdr.e_ident[EI_CLASS] == ELFCLASS64; |
| 483 | |
| 484 | /* |
| 485 | * 3 sections will be added to the ELF file. |
| 486 | * +------------------+ |
| 487 | * | rmodule header | |
| 488 | * +------------------+ |
| 489 | * | program | |
| 490 | * +------------------+ |
| 491 | * | relocations | |
| 492 | * +------------------+ |
| 493 | */ |
| 494 | |
| 495 | /* Create buffer for header and relocations. */ |
| 496 | rmod_data_size = sizeof(struct rmodule_header); |
| 497 | if (bit64) |
| 498 | rmod_data_size += ctx->nrelocs * sizeof(Elf64_Addr); |
| 499 | else |
| 500 | rmod_data_size += ctx->nrelocs * sizeof(Elf32_Addr); |
| 501 | |
| 502 | if (buffer_create(&rmod_data, rmod_data_size, "rmod")) |
| 503 | return -1; |
| 504 | |
| 505 | buffer_splice(&rmod_header, &rmod_data, |
| 506 | 0, sizeof(struct rmodule_header)); |
| 507 | buffer_clone(&relocs, &rmod_data); |
| 508 | buffer_seek(&relocs, sizeof(struct rmodule_header)); |
| 509 | |
| 510 | /* Reset current location. */ |
| 511 | buffer_set_size(&rmod_header, 0); |
| 512 | buffer_set_size(&relocs, 0); |
| 513 | |
| 514 | /* Program contents. */ |
| 515 | buffer_splice(&program, in, ctx->phdr->p_offset, ctx->phdr->p_filesz); |
| 516 | |
| 517 | /* Create ELF writer with modified entry point. */ |
| 518 | memcpy(&ehdr, &ctx->pelf.ehdr, sizeof(ehdr)); |
Aaron Durbin | 4fde5a6 | 2014-03-07 15:11:53 -0600 | [diff] [blame] | 519 | ew = elf_writer_init(&ehdr); |
| 520 | |
| 521 | if (ew == NULL) { |
| 522 | ERROR("Failed to create ELF writer.\n"); |
| 523 | buffer_delete(&rmod_data); |
| 524 | return -1; |
| 525 | } |
| 526 | |
| 527 | /* Write out rmodule_header. */ |
| 528 | ctx->xdr->put16(&rmod_header, RMODULE_MAGIC); |
| 529 | ctx->xdr->put8(&rmod_header, RMODULE_VERSION_1); |
| 530 | ctx->xdr->put8(&rmod_header, 0); |
| 531 | /* payload_begin_offset */ |
| 532 | loc = sizeof(struct rmodule_header); |
| 533 | ctx->xdr->put32(&rmod_header, loc); |
| 534 | /* payload_end_offset */ |
| 535 | loc += ctx->phdr->p_filesz; |
| 536 | ctx->xdr->put32(&rmod_header, loc); |
| 537 | /* relocations_begin_offset */ |
| 538 | ctx->xdr->put32(&rmod_header, loc); |
| 539 | /* relocations_end_offset */ |
| 540 | if (bit64) |
| 541 | loc += ctx->nrelocs * sizeof(Elf64_Addr); |
| 542 | else |
| 543 | loc += ctx->nrelocs * sizeof(Elf32_Addr); |
| 544 | ctx->xdr->put32(&rmod_header, loc); |
| 545 | /* module_link_start_address */ |
Aaron Durbin | 051a181 | 2015-09-08 15:52:01 -0500 | [diff] [blame] | 546 | ctx->xdr->put32(&rmod_header, ctx->phdr->p_vaddr); |
Aaron Durbin | 4fde5a6 | 2014-03-07 15:11:53 -0600 | [diff] [blame] | 547 | /* module_program_size */ |
Aaron Durbin | 051a181 | 2015-09-08 15:52:01 -0500 | [diff] [blame] | 548 | ctx->xdr->put32(&rmod_header, ctx->phdr->p_memsz); |
Aaron Durbin | 4fde5a6 | 2014-03-07 15:11:53 -0600 | [diff] [blame] | 549 | /* module_entry_point */ |
Aaron Durbin | 051a181 | 2015-09-08 15:52:01 -0500 | [diff] [blame] | 550 | ctx->xdr->put32(&rmod_header, ctx->pelf.ehdr.e_entry); |
Aaron Durbin | 4fde5a6 | 2014-03-07 15:11:53 -0600 | [diff] [blame] | 551 | /* parameters_begin */ |
| 552 | ctx->xdr->put32(&rmod_header, ctx->parameters_begin); |
| 553 | /* parameters_end */ |
| 554 | ctx->xdr->put32(&rmod_header, ctx->parameters_end); |
| 555 | /* bss_begin */ |
| 556 | ctx->xdr->put32(&rmod_header, ctx->bss_begin); |
| 557 | /* bss_end */ |
| 558 | ctx->xdr->put32(&rmod_header, ctx->bss_end); |
| 559 | /* padding[4] */ |
| 560 | ctx->xdr->put32(&rmod_header, 0); |
| 561 | ctx->xdr->put32(&rmod_header, 0); |
| 562 | ctx->xdr->put32(&rmod_header, 0); |
| 563 | ctx->xdr->put32(&rmod_header, 0); |
| 564 | |
| 565 | /* Write the relocations. */ |
Sol Boucher | 0e53931 | 2015-03-05 15:38:03 -0800 | [diff] [blame] | 566 | for (unsigned i = 0; i < ctx->nrelocs; i++) { |
Aaron Durbin | 4fde5a6 | 2014-03-07 15:11:53 -0600 | [diff] [blame] | 567 | if (bit64) |
| 568 | ctx->xdr->put64(&relocs, ctx->emitted_relocs[i]); |
| 569 | else |
| 570 | ctx->xdr->put32(&relocs, ctx->emitted_relocs[i]); |
| 571 | } |
| 572 | |
| 573 | total_size = 0; |
| 574 | addr = 0; |
| 575 | |
| 576 | /* |
| 577 | * There are 2 cases to deal with. The program has a large NOBITS |
| 578 | * section and the relocations can fit entirely within occupied memory |
| 579 | * region for the program. The other is that the relocations increase |
| 580 | * the memory footprint of the program if it was loaded directly into |
Frans Hendriks | 166cbde | 2018-11-22 14:21:12 +0100 | [diff] [blame] | 581 | * the region it would run. The rmodule header is a fixed cost that |
Aaron Durbin | 4fde5a6 | 2014-03-07 15:11:53 -0600 | [diff] [blame] | 582 | * is considered a part of the program. |
| 583 | */ |
| 584 | total_size += buffer_size(&rmod_header); |
Aaron Durbin | 518a322 | 2014-08-26 13:52:30 -0500 | [diff] [blame] | 585 | if (buffer_size(&relocs) + ctx->phdr->p_filesz > ctx->phdr->p_memsz) { |
Aaron Durbin | 4fde5a6 | 2014-03-07 15:11:53 -0600 | [diff] [blame] | 586 | total_size += buffer_size(&relocs); |
| 587 | total_size += ctx->phdr->p_filesz; |
Aaron Durbin | 518a322 | 2014-08-26 13:52:30 -0500 | [diff] [blame] | 588 | } else { |
| 589 | total_size += ctx->phdr->p_memsz; |
Aaron Durbin | 4fde5a6 | 2014-03-07 15:11:53 -0600 | [diff] [blame] | 590 | } |
| 591 | |
| 592 | ret = add_section(ew, &rmod_header, ".header", addr, |
| 593 | buffer_size(&rmod_header)); |
| 594 | if (ret < 0) |
| 595 | goto out; |
| 596 | addr += buffer_size(&rmod_header); |
| 597 | |
| 598 | ret = add_section(ew, &program, ".program", addr, ctx->phdr->p_filesz); |
| 599 | if (ret < 0) |
| 600 | goto out; |
| 601 | addr += ctx->phdr->p_filesz; |
| 602 | |
Furquan Shaikh | b237c10 | 2014-08-26 14:59:36 -0700 | [diff] [blame] | 603 | if (ctx->nrelocs) { |
| 604 | ret = add_section(ew, &relocs, ".relocs", addr, |
| 605 | buffer_size(&relocs)); |
| 606 | if (ret < 0) |
| 607 | goto out; |
| 608 | addr += buffer_size(&relocs); |
| 609 | } |
Aaron Durbin | 4fde5a6 | 2014-03-07 15:11:53 -0600 | [diff] [blame] | 610 | |
| 611 | if (total_size != addr) { |
| 612 | ret = add_section(ew, NULL, ".empty", addr, total_size - addr); |
| 613 | if (ret < 0) |
| 614 | goto out; |
| 615 | } |
| 616 | |
| 617 | /* |
| 618 | * Ensure last section has a memory usage that meets the required |
| 619 | * total size of the program in memory. |
| 620 | */ |
| 621 | |
| 622 | ret = elf_writer_serialize(ew, out); |
| 623 | if (ret < 0) |
| 624 | ERROR("Failed to serialize ELF to buffer.\n"); |
| 625 | |
| 626 | out: |
| 627 | buffer_delete(&rmod_data); |
| 628 | elf_writer_destroy(ew); |
| 629 | |
| 630 | return ret; |
| 631 | } |
| 632 | |
Aaron Durbin | b39a974 | 2015-09-08 17:24:04 -0500 | [diff] [blame] | 633 | int rmodule_init(struct rmod_context *ctx, const struct buffer *elfin) |
Aaron Durbin | 4fde5a6 | 2014-03-07 15:11:53 -0600 | [diff] [blame] | 634 | { |
Aaron Durbin | 4fde5a6 | 2014-03-07 15:11:53 -0600 | [diff] [blame] | 635 | struct parsed_elf *pelf; |
Furquan Shaikh | 161d233 | 2016-05-26 14:41:02 -0700 | [diff] [blame] | 636 | size_t i; |
Aaron Durbin | 4fde5a6 | 2014-03-07 15:11:53 -0600 | [diff] [blame] | 637 | int ret; |
| 638 | |
| 639 | ret = -1; |
Aaron Durbin | 051a181 | 2015-09-08 15:52:01 -0500 | [diff] [blame] | 640 | memset(ctx, 0, sizeof(*ctx)); |
| 641 | pelf = &ctx->pelf; |
Aaron Durbin | 4fde5a6 | 2014-03-07 15:11:53 -0600 | [diff] [blame] | 642 | |
| 643 | if (parse_elf(elfin, pelf, ELF_PARSE_ALL)) { |
| 644 | ERROR("Couldn't parse ELF!\n"); |
| 645 | return -1; |
| 646 | } |
| 647 | |
| 648 | /* Only allow executables to be turned into rmodules. */ |
| 649 | if (pelf->ehdr.e_type != ET_EXEC) { |
| 650 | ERROR("ELF is not an executable: %u.\n", pelf->ehdr.e_type); |
| 651 | goto out; |
| 652 | } |
| 653 | |
| 654 | /* Determine if architecture is supported. */ |
| 655 | for (i = 0; i < ARRAY_SIZE(reloc_ops); i++) { |
| 656 | if (reloc_ops[i].arch == pelf->ehdr.e_machine) { |
Aaron Durbin | 051a181 | 2015-09-08 15:52:01 -0500 | [diff] [blame] | 657 | ctx->ops = &reloc_ops[i]; |
Aaron Durbin | 4fde5a6 | 2014-03-07 15:11:53 -0600 | [diff] [blame] | 658 | break; |
| 659 | } |
| 660 | } |
| 661 | |
Aaron Durbin | 051a181 | 2015-09-08 15:52:01 -0500 | [diff] [blame] | 662 | if (ctx->ops == NULL) { |
Aaron Durbin | 4fde5a6 | 2014-03-07 15:11:53 -0600 | [diff] [blame] | 663 | ERROR("ELF is unsupported arch: %u.\n", pelf->ehdr.e_machine); |
| 664 | goto out; |
| 665 | } |
| 666 | |
| 667 | /* Set the endian ops. */ |
Aaron Durbin | 051a181 | 2015-09-08 15:52:01 -0500 | [diff] [blame] | 668 | if (ctx->pelf.ehdr.e_ident[EI_DATA] == ELFDATA2MSB) |
| 669 | ctx->xdr = &xdr_be; |
Aaron Durbin | 4fde5a6 | 2014-03-07 15:11:53 -0600 | [diff] [blame] | 670 | else |
Aaron Durbin | 051a181 | 2015-09-08 15:52:01 -0500 | [diff] [blame] | 671 | ctx->xdr = &xdr_le; |
Aaron Durbin | 4fde5a6 | 2014-03-07 15:11:53 -0600 | [diff] [blame] | 672 | |
Aaron Durbin | 051a181 | 2015-09-08 15:52:01 -0500 | [diff] [blame] | 673 | if (find_program_segment(ctx)) |
Aaron Durbin | 4fde5a6 | 2014-03-07 15:11:53 -0600 | [diff] [blame] | 674 | goto out; |
| 675 | |
Aaron Durbin | 051a181 | 2015-09-08 15:52:01 -0500 | [diff] [blame] | 676 | if (filter_relocation_sections(ctx)) |
| 677 | goto out; |
| 678 | |
| 679 | ret = 0; |
| 680 | |
| 681 | out: |
| 682 | return ret; |
| 683 | } |
| 684 | |
Aaron Durbin | b39a974 | 2015-09-08 17:24:04 -0500 | [diff] [blame] | 685 | void rmodule_cleanup(struct rmod_context *ctx) |
Aaron Durbin | 051a181 | 2015-09-08 15:52:01 -0500 | [diff] [blame] | 686 | { |
| 687 | free(ctx->emitted_relocs); |
| 688 | parsed_elf_destroy(&ctx->pelf); |
| 689 | } |
| 690 | |
| 691 | int rmodule_create(const struct buffer *elfin, struct buffer *elfout) |
| 692 | { |
| 693 | struct rmod_context ctx; |
| 694 | int ret = -1; |
| 695 | |
| 696 | if (rmodule_init(&ctx, elfin)) |
Aaron Durbin | 4fde5a6 | 2014-03-07 15:11:53 -0600 | [diff] [blame] | 697 | goto out; |
| 698 | |
Aaron Durbin | b39a974 | 2015-09-08 17:24:04 -0500 | [diff] [blame] | 699 | if (rmodule_collect_relocations(&ctx, NULL)) |
Aaron Durbin | 4fde5a6 | 2014-03-07 15:11:53 -0600 | [diff] [blame] | 700 | goto out; |
| 701 | |
Aaron Durbin | 051a181 | 2015-09-08 15:52:01 -0500 | [diff] [blame] | 702 | if (populate_rmodule_info(&ctx)) |
Aaron Durbin | 4fde5a6 | 2014-03-07 15:11:53 -0600 | [diff] [blame] | 703 | goto out; |
| 704 | |
| 705 | if (write_elf(&ctx, elfin, elfout)) |
| 706 | goto out; |
| 707 | |
| 708 | ret = 0; |
| 709 | |
| 710 | out: |
Aaron Durbin | 051a181 | 2015-09-08 15:52:01 -0500 | [diff] [blame] | 711 | rmodule_cleanup(&ctx); |
Aaron Durbin | 4fde5a6 | 2014-03-07 15:11:53 -0600 | [diff] [blame] | 712 | return ret; |
| 713 | } |
Aaron Durbin | 694fd13 | 2015-10-28 11:39:34 -0500 | [diff] [blame] | 714 | |
| 715 | static void rmod_deserialize(struct rmodule_header *rmod, struct buffer *buff, |
| 716 | struct xdr *xdr) |
| 717 | { |
| 718 | rmod->magic = xdr->get16(buff); |
| 719 | rmod->version = xdr->get8(buff); |
| 720 | rmod->type = xdr->get8(buff); |
| 721 | rmod->payload_begin_offset = xdr->get32(buff); |
| 722 | rmod->payload_end_offset = xdr->get32(buff); |
| 723 | rmod->relocations_begin_offset = xdr->get32(buff); |
| 724 | rmod->relocations_end_offset = xdr->get32(buff); |
| 725 | rmod->module_link_start_address = xdr->get32(buff); |
| 726 | rmod->module_program_size = xdr->get32(buff); |
| 727 | rmod->module_entry_point = xdr->get32(buff); |
| 728 | rmod->parameters_begin = xdr->get32(buff); |
| 729 | rmod->parameters_end = xdr->get32(buff); |
| 730 | rmod->bss_begin = xdr->get32(buff); |
| 731 | rmod->bss_end = xdr->get32(buff); |
| 732 | rmod->padding[0] = xdr->get32(buff); |
| 733 | rmod->padding[1] = xdr->get32(buff); |
| 734 | rmod->padding[2] = xdr->get32(buff); |
| 735 | rmod->padding[3] = xdr->get32(buff); |
| 736 | } |
| 737 | |
| 738 | int rmodule_stage_to_elf(Elf64_Ehdr *ehdr, struct buffer *buff) |
| 739 | { |
| 740 | struct buffer reader; |
| 741 | struct buffer elf_out; |
| 742 | struct rmodule_header rmod; |
| 743 | struct xdr *xdr; |
| 744 | struct elf_writer *ew; |
| 745 | Elf64_Shdr shdr; |
| 746 | int bit64; |
| 747 | size_t payload_sz; |
| 748 | const char *section_name = ".program"; |
| 749 | const size_t input_sz = buffer_size(buff); |
| 750 | |
| 751 | buffer_clone(&reader, buff); |
| 752 | |
| 753 | xdr = (ehdr->e_ident[EI_DATA] == ELFDATA2MSB) ? &xdr_be : &xdr_le; |
| 754 | bit64 = ehdr->e_ident[EI_CLASS] == ELFCLASS64; |
| 755 | |
| 756 | rmod_deserialize(&rmod, &reader, xdr); |
| 757 | |
| 758 | /* Indicate that file is not an rmodule if initial checks fail. */ |
| 759 | if (rmod.magic != RMODULE_MAGIC) |
| 760 | return 1; |
| 761 | if (rmod.version != RMODULE_VERSION_1) |
| 762 | return 1; |
| 763 | |
| 764 | if (rmod.payload_begin_offset > input_sz || |
| 765 | rmod.payload_end_offset > input_sz || |
| 766 | rmod.relocations_begin_offset > input_sz || |
| 767 | rmod.relocations_end_offset > input_sz) { |
| 768 | ERROR("Rmodule fields out of bounds.\n"); |
| 769 | return -1; |
| 770 | } |
| 771 | |
| 772 | ehdr->e_entry = rmod.module_entry_point; |
| 773 | ew = elf_writer_init(ehdr); |
| 774 | |
| 775 | if (ew == NULL) |
| 776 | return -1; |
| 777 | |
| 778 | payload_sz = rmod.payload_end_offset - rmod.payload_begin_offset; |
| 779 | memset(&shdr, 0, sizeof(shdr)); |
| 780 | shdr.sh_type = SHT_PROGBITS; |
| 781 | shdr.sh_flags = SHF_WRITE | SHF_ALLOC | SHF_EXECINSTR; |
| 782 | shdr.sh_addr = rmod.module_link_start_address; |
| 783 | shdr.sh_size = payload_sz; |
| 784 | buffer_splice(&reader, buff, rmod.payload_begin_offset, payload_sz); |
| 785 | |
| 786 | if (elf_writer_add_section(ew, &shdr, &reader, section_name)) { |
| 787 | ERROR("Unable to add ELF section: %s\n", section_name); |
| 788 | elf_writer_destroy(ew); |
| 789 | return -1; |
| 790 | } |
| 791 | |
| 792 | if (payload_sz != rmod.module_program_size) { |
| 793 | struct buffer b; |
| 794 | |
| 795 | buffer_init(&b, NULL, NULL, 0); |
| 796 | memset(&shdr, 0, sizeof(shdr)); |
| 797 | shdr.sh_type = SHT_NOBITS; |
| 798 | shdr.sh_flags = SHF_WRITE | SHF_ALLOC; |
| 799 | shdr.sh_addr = rmod.module_link_start_address + payload_sz; |
| 800 | shdr.sh_size = rmod.module_program_size - payload_sz; |
| 801 | if (elf_writer_add_section(ew, &shdr, &b, ".empty")) { |
| 802 | ERROR("Unable to add ELF section: .empty\n"); |
| 803 | elf_writer_destroy(ew); |
| 804 | return -1; |
| 805 | } |
| 806 | } |
| 807 | |
| 808 | /* Provide a section symbol so the relcoations can reference that. */ |
| 809 | if (elf_writer_add_symbol(ew, section_name, section_name, shdr.sh_addr, |
| 810 | 0, STB_LOCAL, STT_SECTION)) { |
| 811 | ERROR("Unable to add section symbol to ELF.\n"); |
| 812 | elf_writer_destroy(ew); |
| 813 | return -1; |
| 814 | } |
| 815 | |
| 816 | /* Add symbols for the parameters if they are non-zero. */ |
| 817 | if (rmod.parameters_begin != rmod.parameters_end) { |
| 818 | int ret = 0; |
| 819 | |
| 820 | ret |= elf_writer_add_symbol(ew, "_rmodule_params", |
| 821 | section_name, |
| 822 | rmod.parameters_begin, 0, |
| 823 | STB_GLOBAL, STT_NOTYPE); |
| 824 | ret |= elf_writer_add_symbol(ew, "_ermodule_params", |
| 825 | section_name, |
| 826 | rmod.parameters_end, 0, |
| 827 | STB_GLOBAL, STT_NOTYPE); |
| 828 | |
| 829 | if (ret != 0) { |
| 830 | ERROR("Unable to add module params symbols to ELF\n"); |
| 831 | elf_writer_destroy(ew); |
| 832 | return -1; |
| 833 | } |
| 834 | } |
| 835 | |
| 836 | if (elf_writer_add_symbol(ew, "_bss", section_name, rmod.bss_begin, 0, |
| 837 | STB_GLOBAL, STT_NOTYPE) || |
| 838 | elf_writer_add_symbol(ew, "_ebss", section_name, rmod.bss_end, 0, |
| 839 | STB_GLOBAL, STT_NOTYPE)) { |
| 840 | ERROR("Unable to add bss symbols to ELF\n"); |
| 841 | elf_writer_destroy(ew); |
| 842 | return -1; |
| 843 | } |
| 844 | |
| 845 | ssize_t relocs_sz = rmod.relocations_end_offset; |
| 846 | relocs_sz -= rmod.relocations_begin_offset; |
| 847 | buffer_splice(&reader, buff, rmod.relocations_begin_offset, relocs_sz); |
| 848 | while (relocs_sz > 0) { |
| 849 | Elf64_Addr addr; |
| 850 | |
| 851 | if (bit64) { |
| 852 | relocs_sz -= sizeof(Elf64_Addr); |
| 853 | addr = xdr->get64(&reader); |
| 854 | } else { |
| 855 | relocs_sz -= sizeof(Elf32_Addr); |
| 856 | addr = xdr->get32(&reader); |
| 857 | } |
| 858 | |
| 859 | /* Skip any relocations that are below the link address. */ |
| 860 | if (addr < rmod.module_link_start_address) |
| 861 | continue; |
| 862 | |
| 863 | if (elf_writer_add_rel(ew, section_name, addr)) { |
| 864 | ERROR("Relocation addition failure.\n"); |
| 865 | elf_writer_destroy(ew); |
| 866 | return -1; |
| 867 | } |
| 868 | } |
| 869 | |
| 870 | if (elf_writer_serialize(ew, &elf_out)) { |
| 871 | ERROR("ELF writer serialize failure.\n"); |
| 872 | elf_writer_destroy(ew); |
| 873 | return -1; |
| 874 | } |
| 875 | |
| 876 | elf_writer_destroy(ew); |
| 877 | |
| 878 | /* Flip buffer with the created ELF one. */ |
| 879 | buffer_delete(buff); |
| 880 | *buff = elf_out; |
| 881 | |
| 882 | return 0; |
| 883 | } |