1 /****************************************************************************/ 2 /* 3 * QEMU bFLT binary loader. Based on linux/fs/binfmt_flat.c 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; either version 2 of the License, or 8 * (at your option) any later version. 9 * 10 * This program is distributed in the hope that it will be useful, 11 * but WITHOUT ANY WARRANTY; without even the implied warranty of 12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 * GNU General Public License for more details. 14 * 15 * You should have received a copy of the GNU General Public License 16 * along with this program; if not, see <http://www.gnu.org/licenses/>. 17 * 18 * Copyright (C) 2006 CodeSourcery. 19 * Copyright (C) 2000-2003 David McCullough <davidm@snapgear.com> 20 * Copyright (C) 2002 Greg Ungerer <gerg@snapgear.com> 21 * Copyright (C) 2002 SnapGear, by Paul Dale <pauli@snapgear.com> 22 * Copyright (C) 2000, 2001 Lineo, by David McCullough <davidm@lineo.com> 23 * based heavily on: 24 * 25 * linux/fs/binfmt_aout.c: 26 * Copyright (C) 1991, 1992, 1996 Linus Torvalds 27 * linux/fs/binfmt_flat.c for 2.0 kernel 28 * Copyright (C) 1998 Kenneth Albanowski <kjahds@kjahds.com> 29 * JAN/99 -- coded full program relocation (gerg@snapgear.com) 30 */ 31 32 /* ??? ZFLAT and shared library support is currently disabled. */ 33 34 /****************************************************************************/ 35 36 #include "qemu/osdep.h" 37 38 #include "qemu.h" 39 #include "user-internals.h" 40 #include "loader.h" 41 #include "user-mmap.h" 42 #include "flat.h" 43 #include "target_flat.h" 44 45 //#define DEBUG 46 47 #ifdef DEBUG 48 #define DBG_FLT(...) printf(__VA_ARGS__) 49 #else 50 #define DBG_FLT(...) 51 #endif 52 53 #define RELOC_FAILED 0xff00ff01 /* Relocation incorrect somewhere */ 54 #define UNLOADED_LIB 0x7ff000ff /* Placeholder for unused library */ 55 56 struct lib_info { 57 abi_ulong start_code; /* Start of text segment */ 58 abi_ulong start_data; /* Start of data segment */ 59 abi_ulong end_data; /* Start of bss section */ 60 abi_ulong start_brk; /* End of data segment */ 61 abi_ulong text_len; /* Length of text segment */ 62 abi_ulong entry; /* Start address for this module */ 63 abi_ulong build_date; /* When this one was compiled */ 64 short loaded; /* Has this library been loaded? */ 65 }; 66 67 #ifdef CONFIG_BINFMT_SHARED_FLAT 68 static int load_flat_shared_library(int id, struct lib_info *p); 69 #endif 70 71 struct linux_binprm; 72 73 /****************************************************************************/ 74 /* 75 * create_flat_tables() parses the env- and arg-strings in new user 76 * memory and creates the pointer tables from them, and puts their 77 * addresses on the "stack", returning the new stack pointer value. 78 */ 79 80 /* Push a block of strings onto the guest stack. */ 81 static abi_ulong copy_strings(abi_ulong p, int n, char **s) 82 { 83 int len; 84 85 while (n-- > 0) { 86 len = strlen(s[n]) + 1; 87 p -= len; 88 memcpy_to_target(p, s[n], len); 89 } 90 91 return p; 92 } 93 94 static int target_pread(int fd, abi_ulong ptr, abi_ulong len, 95 abi_ulong offset) 96 { 97 void *buf; 98 int ret; 99 100 buf = lock_user(VERIFY_WRITE, ptr, len, 0); 101 if (!buf) { 102 return -EFAULT; 103 } 104 ret = pread(fd, buf, len, offset); 105 if (ret < 0) { 106 ret = -errno; 107 } 108 unlock_user(buf, ptr, len); 109 return ret; 110 } 111 /****************************************************************************/ 112 113 #ifdef CONFIG_BINFMT_ZFLAT 114 115 #include <linux/zlib.h> 116 117 #define LBUFSIZE 4000 118 119 /* gzip flag byte */ 120 #define ASCII_FLAG 0x01 /* bit 0 set: file probably ASCII text */ 121 #define CONTINUATION 0x02 /* bit 1 set: continuation of multi-part gzip file */ 122 #define EXTRA_FIELD 0x04 /* bit 2 set: extra field present */ 123 #define ORIG_NAME 0x08 /* bit 3 set: original file name present */ 124 #define COMMENT 0x10 /* bit 4 set: file comment present */ 125 #define ENCRYPTED 0x20 /* bit 5 set: file is encrypted */ 126 #define RESERVED 0xC0 /* bit 6,7: reserved */ 127 128 static int decompress_exec( 129 struct linux_binprm *bprm, 130 unsigned long offset, 131 char *dst, 132 long len, 133 int fd) 134 { 135 unsigned char *buf; 136 z_stream strm; 137 loff_t fpos; 138 int ret, retval; 139 140 DBG_FLT("decompress_exec(offset=%x,buf=%x,len=%x)\n",(int)offset, (int)dst, (int)len); 141 142 memset(&strm, 0, sizeof(strm)); 143 strm.workspace = kmalloc(zlib_inflate_workspacesize(), GFP_KERNEL); 144 if (strm.workspace == NULL) { 145 DBG_FLT("binfmt_flat: no memory for decompress workspace\n"); 146 return -ENOMEM; 147 } 148 buf = kmalloc(LBUFSIZE, GFP_KERNEL); 149 if (buf == NULL) { 150 DBG_FLT("binfmt_flat: no memory for read buffer\n"); 151 retval = -ENOMEM; 152 goto out_free; 153 } 154 155 /* Read in first chunk of data and parse gzip header. */ 156 fpos = offset; 157 ret = bprm->file->f_op->read(bprm->file, buf, LBUFSIZE, &fpos); 158 159 strm.next_in = buf; 160 strm.avail_in = ret; 161 strm.total_in = 0; 162 163 retval = -ENOEXEC; 164 165 /* Check minimum size -- gzip header */ 166 if (ret < 10) { 167 DBG_FLT("binfmt_flat: file too small?\n"); 168 goto out_free_buf; 169 } 170 171 /* Check gzip magic number */ 172 if ((buf[0] != 037) || ((buf[1] != 0213) && (buf[1] != 0236))) { 173 DBG_FLT("binfmt_flat: unknown compression magic?\n"); 174 goto out_free_buf; 175 } 176 177 /* Check gzip method */ 178 if (buf[2] != 8) { 179 DBG_FLT("binfmt_flat: unknown compression method?\n"); 180 goto out_free_buf; 181 } 182 /* Check gzip flags */ 183 if ((buf[3] & ENCRYPTED) || (buf[3] & CONTINUATION) || 184 (buf[3] & RESERVED)) { 185 DBG_FLT("binfmt_flat: unknown flags?\n"); 186 goto out_free_buf; 187 } 188 189 ret = 10; 190 if (buf[3] & EXTRA_FIELD) { 191 ret += 2 + buf[10] + (buf[11] << 8); 192 if (unlikely(LBUFSIZE == ret)) { 193 DBG_FLT("binfmt_flat: buffer overflow (EXTRA)?\n"); 194 goto out_free_buf; 195 } 196 } 197 if (buf[3] & ORIG_NAME) { 198 for (; ret < LBUFSIZE && (buf[ret] != 0); ret++) 199 ; 200 if (unlikely(LBUFSIZE == ret)) { 201 DBG_FLT("binfmt_flat: buffer overflow (ORIG_NAME)?\n"); 202 goto out_free_buf; 203 } 204 } 205 if (buf[3] & COMMENT) { 206 for (; ret < LBUFSIZE && (buf[ret] != 0); ret++) 207 ; 208 if (unlikely(LBUFSIZE == ret)) { 209 DBG_FLT("binfmt_flat: buffer overflow (COMMENT)?\n"); 210 goto out_free_buf; 211 } 212 } 213 214 strm.next_in += ret; 215 strm.avail_in -= ret; 216 217 strm.next_out = dst; 218 strm.avail_out = len; 219 strm.total_out = 0; 220 221 if (zlib_inflateInit2(&strm, -MAX_WBITS) != Z_OK) { 222 DBG_FLT("binfmt_flat: zlib init failed?\n"); 223 goto out_free_buf; 224 } 225 226 while ((ret = zlib_inflate(&strm, Z_NO_FLUSH)) == Z_OK) { 227 ret = bprm->file->f_op->read(bprm->file, buf, LBUFSIZE, &fpos); 228 if (ret <= 0) 229 break; 230 if (is_error(ret)) { 231 break; 232 } 233 len -= ret; 234 235 strm.next_in = buf; 236 strm.avail_in = ret; 237 strm.total_in = 0; 238 } 239 240 if (ret < 0) { 241 DBG_FLT("binfmt_flat: decompression failed (%d), %s\n", 242 ret, strm.msg); 243 goto out_zlib; 244 } 245 246 retval = 0; 247 out_zlib: 248 zlib_inflateEnd(&strm); 249 out_free_buf: 250 kfree(buf); 251 out_free: 252 kfree(strm.workspace); 253 out: 254 return retval; 255 } 256 257 #endif /* CONFIG_BINFMT_ZFLAT */ 258 259 /****************************************************************************/ 260 261 static abi_ulong 262 calc_reloc(abi_ulong r, struct lib_info *p, int curid, int internalp) 263 { 264 abi_ulong addr; 265 int id; 266 abi_ulong start_brk; 267 abi_ulong start_data; 268 abi_ulong text_len; 269 abi_ulong start_code; 270 271 #ifdef CONFIG_BINFMT_SHARED_FLAT 272 #error needs checking 273 if (r == 0) 274 id = curid; /* Relocs of 0 are always self referring */ 275 else { 276 id = (r >> 24) & 0xff; /* Find ID for this reloc */ 277 r &= 0x00ffffff; /* Trim ID off here */ 278 } 279 if (id >= MAX_SHARED_LIBS) { 280 fprintf(stderr, "BINFMT_FLAT: reference 0x%x to shared library %d\n", 281 (unsigned) r, id); 282 goto failed; 283 } 284 if (curid != id) { 285 if (internalp) { 286 fprintf(stderr, "BINFMT_FLAT: reloc address 0x%x not " 287 "in same module (%d != %d)\n", 288 (unsigned) r, curid, id); 289 goto failed; 290 } else if (!p[id].loaded && is_error(load_flat_shared_library(id, p))) { 291 fprintf(stderr, "BINFMT_FLAT: failed to load library %d\n", id); 292 goto failed; 293 } 294 /* Check versioning information (i.e. time stamps) */ 295 if (p[id].build_date && p[curid].build_date 296 && p[curid].build_date < p[id].build_date) { 297 fprintf(stderr, "BINFMT_FLAT: library %d is younger than %d\n", 298 id, curid); 299 goto failed; 300 } 301 } 302 #else 303 id = 0; 304 #endif 305 306 start_brk = p[id].start_brk; 307 start_data = p[id].start_data; 308 start_code = p[id].start_code; 309 text_len = p[id].text_len; 310 311 if (!flat_reloc_valid(r, start_brk - start_data + text_len)) { 312 fprintf(stderr, "BINFMT_FLAT: reloc outside program 0x%x " 313 "(0 - 0x%x/0x%x)\n", 314 (int) r,(int)(start_brk-start_code),(int)text_len); 315 goto failed; 316 } 317 318 if (r < text_len) /* In text segment */ 319 addr = r + start_code; 320 else /* In data segment */ 321 addr = r - text_len + start_data; 322 323 /* Range checked already above so doing the range tests is redundant...*/ 324 return(addr); 325 326 failed: 327 abort(); 328 return RELOC_FAILED; 329 } 330 331 /****************************************************************************/ 332 333 /* ??? This does not handle endianness correctly. */ 334 static void old_reloc(struct lib_info *libinfo, uint32_t rl) 335 { 336 #ifdef DEBUG 337 const char *segment[] = { "TEXT", "DATA", "BSS", "*UNKNOWN*" }; 338 #endif 339 uint32_t *ptr; 340 uint32_t offset; 341 int reloc_type; 342 343 offset = rl & 0x3fffffff; 344 reloc_type = rl >> 30; 345 /* ??? How to handle this? */ 346 #if defined(CONFIG_COLDFIRE) 347 ptr = (uint32_t *) ((unsigned long) libinfo->start_code + offset); 348 #else 349 ptr = (uint32_t *) ((unsigned long) libinfo->start_data + offset); 350 #endif 351 352 #ifdef DEBUG 353 fprintf(stderr, "Relocation of variable at DATASEG+%x " 354 "(address %p, currently %x) into segment %s\n", 355 offset, ptr, (int)*ptr, segment[reloc_type]); 356 #endif 357 358 switch (reloc_type) { 359 case OLD_FLAT_RELOC_TYPE_TEXT: 360 *ptr += libinfo->start_code; 361 break; 362 case OLD_FLAT_RELOC_TYPE_DATA: 363 *ptr += libinfo->start_data; 364 break; 365 case OLD_FLAT_RELOC_TYPE_BSS: 366 *ptr += libinfo->end_data; 367 break; 368 default: 369 fprintf(stderr, "BINFMT_FLAT: Unknown relocation type=%x\n", 370 reloc_type); 371 break; 372 } 373 DBG_FLT("Relocation became %x\n", (int)*ptr); 374 } 375 376 /****************************************************************************/ 377 378 static int load_flat_file(struct linux_binprm * bprm, 379 struct lib_info *libinfo, int id, abi_ulong *extra_stack) 380 { 381 struct flat_hdr * hdr; 382 abi_ulong textpos = 0, datapos = 0; 383 abi_long result; 384 abi_ulong realdatastart = 0; 385 abi_ulong text_len, data_len, bss_len, stack_len, flags; 386 abi_ulong extra; 387 abi_ulong reloc = 0, rp; 388 int i, rev, relocs = 0; 389 abi_ulong fpos; 390 abi_ulong start_code; 391 abi_ulong indx_len; 392 393 hdr = ((struct flat_hdr *) bprm->buf); /* exec-header */ 394 395 text_len = ntohl(hdr->data_start); 396 data_len = ntohl(hdr->data_end) - ntohl(hdr->data_start); 397 bss_len = ntohl(hdr->bss_end) - ntohl(hdr->data_end); 398 stack_len = ntohl(hdr->stack_size); 399 if (extra_stack) { 400 stack_len += *extra_stack; 401 *extra_stack = stack_len; 402 } 403 relocs = ntohl(hdr->reloc_count); 404 flags = ntohl(hdr->flags); 405 rev = ntohl(hdr->rev); 406 407 DBG_FLT("BINFMT_FLAT: Loading file: %s\n", bprm->filename); 408 409 if (rev != FLAT_VERSION && rev != OLD_FLAT_VERSION) { 410 fprintf(stderr, "BINFMT_FLAT: bad magic/rev (0x%x, need 0x%x)\n", 411 rev, (int) FLAT_VERSION); 412 return -ENOEXEC; 413 } 414 415 /* Don't allow old format executables to use shared libraries */ 416 if (rev == OLD_FLAT_VERSION && id != 0) { 417 fprintf(stderr, "BINFMT_FLAT: shared libraries are not available\n"); 418 return -ENOEXEC; 419 } 420 421 /* 422 * fix up the flags for the older format, there were all kinds 423 * of endian hacks, this only works for the simple cases 424 */ 425 if (rev == OLD_FLAT_VERSION && flat_old_ram_flag(flags)) 426 flags = FLAT_FLAG_RAM; 427 428 #ifndef CONFIG_BINFMT_ZFLAT 429 if (flags & (FLAT_FLAG_GZIP|FLAT_FLAG_GZDATA)) { 430 fprintf(stderr, "Support for ZFLAT executables is not enabled\n"); 431 return -ENOEXEC; 432 } 433 #endif 434 435 /* 436 * calculate the extra space we need to map in 437 */ 438 extra = relocs * sizeof(abi_ulong); 439 if (extra < bss_len + stack_len) 440 extra = bss_len + stack_len; 441 442 /* Add space for library base pointers. Make sure this does not 443 misalign the doesn't misalign the data segment. */ 444 indx_len = MAX_SHARED_LIBS * sizeof(abi_ulong); 445 indx_len = (indx_len + 15) & ~(abi_ulong)15; 446 447 /* 448 * Allocate the address space. 449 */ 450 probe_guest_base(bprm->filename, 0, 451 text_len + data_len + extra + indx_len - 1); 452 453 /* 454 * there are a couple of cases here, the separate code/data 455 * case, and then the fully copied to RAM case which lumps 456 * it all together. 457 */ 458 if ((flags & (FLAT_FLAG_RAM|FLAT_FLAG_GZIP)) == 0) { 459 /* 460 * this should give us a ROM ptr, but if it doesn't we don't 461 * really care 462 */ 463 DBG_FLT("BINFMT_FLAT: ROM mapping of file (we hope)\n"); 464 465 textpos = target_mmap(0, text_len, PROT_READ|PROT_EXEC, 466 MAP_PRIVATE, bprm->src.fd, 0); 467 if (textpos == -1) { 468 fprintf(stderr, "Unable to mmap process text\n"); 469 return -1; 470 } 471 472 realdatastart = target_mmap(0, data_len + extra + indx_len, 473 PROT_READ|PROT_WRITE|PROT_EXEC, 474 MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); 475 476 if (realdatastart == -1) { 477 fprintf(stderr, "Unable to allocate RAM for process data\n"); 478 return realdatastart; 479 } 480 datapos = realdatastart + indx_len; 481 482 DBG_FLT("BINFMT_FLAT: Allocated data+bss+stack (%d bytes): %x\n", 483 (int)(data_len + bss_len + stack_len), (int)datapos); 484 485 fpos = ntohl(hdr->data_start); 486 #ifdef CONFIG_BINFMT_ZFLAT 487 if (flags & FLAT_FLAG_GZDATA) { 488 result = decompress_exec(bprm, fpos, (char *) datapos, 489 data_len + (relocs * sizeof(abi_ulong))) 490 } else 491 #endif 492 { 493 result = target_pread(bprm->src.fd, datapos, 494 data_len + (relocs * sizeof(abi_ulong)), 495 fpos); 496 } 497 if (result < 0) { 498 fprintf(stderr, "Unable to read data+bss\n"); 499 return result; 500 } 501 502 reloc = datapos + (ntohl(hdr->reloc_start) - text_len); 503 504 } else { 505 506 textpos = target_mmap(0, text_len + data_len + extra + indx_len, 507 PROT_READ | PROT_EXEC | PROT_WRITE, 508 MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); 509 if (textpos == -1 ) { 510 fprintf(stderr, "Unable to allocate RAM for process text/data\n"); 511 return -1; 512 } 513 514 realdatastart = textpos + ntohl(hdr->data_start); 515 datapos = realdatastart + indx_len; 516 reloc = (textpos + ntohl(hdr->reloc_start) + indx_len); 517 518 #ifdef CONFIG_BINFMT_ZFLAT 519 #error code needs checking 520 /* 521 * load it all in and treat it like a RAM load from now on 522 */ 523 if (flags & FLAT_FLAG_GZIP) { 524 result = decompress_exec(bprm, sizeof (struct flat_hdr), 525 (((char *) textpos) + sizeof (struct flat_hdr)), 526 (text_len + data_len + (relocs * sizeof(unsigned long)) 527 - sizeof (struct flat_hdr)), 528 0); 529 memmove((void *) datapos, (void *) realdatastart, 530 data_len + (relocs * sizeof(unsigned long))); 531 } else if (flags & FLAT_FLAG_GZDATA) { 532 fpos = 0; 533 result = bprm->file->f_op->read(bprm->file, 534 (char *) textpos, text_len, &fpos); 535 if (!is_error(result)) { 536 result = decompress_exec(bprm, text_len, (char *) datapos, 537 data_len + (relocs * sizeof(unsigned long)), 0); 538 } 539 } 540 else 541 #endif 542 { 543 result = target_pread(bprm->src.fd, textpos, 544 text_len, 0); 545 if (result >= 0) { 546 result = target_pread(bprm->src.fd, datapos, 547 data_len + (relocs * sizeof(abi_ulong)), 548 ntohl(hdr->data_start)); 549 } 550 } 551 if (result < 0) { 552 fprintf(stderr, "Unable to read code+data+bss\n"); 553 return result; 554 } 555 } 556 557 DBG_FLT("Mapping is 0x%x, Entry point is 0x%x, data_start is 0x%x\n", 558 (int)textpos, 0x00ffffff&ntohl(hdr->entry), 559 ntohl(hdr->data_start)); 560 561 /* The main program needs a little extra setup in the task structure */ 562 start_code = textpos + sizeof (struct flat_hdr); 563 564 DBG_FLT("%s %s: TEXT=%x-%x DATA=%x-%x BSS=%x-%x\n", 565 id ? "Lib" : "Load", bprm->filename, 566 (int) start_code, (int) (textpos + text_len), 567 (int) datapos, 568 (int) (datapos + data_len), 569 (int) (datapos + data_len), 570 (int) (((datapos + data_len + bss_len) + 3) & ~3)); 571 572 text_len -= sizeof(struct flat_hdr); /* the real code len */ 573 574 /* Store the current module values into the global library structure */ 575 libinfo[id].start_code = start_code; 576 libinfo[id].start_data = datapos; 577 libinfo[id].end_data = datapos + data_len; 578 libinfo[id].start_brk = datapos + data_len + bss_len; 579 libinfo[id].text_len = text_len; 580 libinfo[id].loaded = 1; 581 libinfo[id].entry = (0x00ffffff & ntohl(hdr->entry)) + textpos; 582 libinfo[id].build_date = ntohl(hdr->build_date); 583 584 /* 585 * We just load the allocations into some temporary memory to 586 * help simplify all this mumbo jumbo 587 * 588 * We've got two different sections of relocation entries. 589 * The first is the GOT which resides at the beginning of the data segment 590 * and is terminated with a -1. This one can be relocated in place. 591 * The second is the extra relocation entries tacked after the image's 592 * data segment. These require a little more processing as the entry is 593 * really an offset into the image which contains an offset into the 594 * image. 595 */ 596 if (flags & FLAT_FLAG_GOTPIC) { 597 rp = datapos; 598 while (1) { 599 abi_ulong addr; 600 if (get_user_ual(addr, rp)) 601 return -EFAULT; 602 if (addr == -1) 603 break; 604 if (addr) { 605 addr = calc_reloc(addr, libinfo, id, 0); 606 if (addr == RELOC_FAILED) 607 return -ENOEXEC; 608 if (put_user_ual(addr, rp)) 609 return -EFAULT; 610 } 611 rp += sizeof(abi_ulong); 612 } 613 } 614 615 /* 616 * Now run through the relocation entries. 617 * We've got to be careful here as C++ produces relocatable zero 618 * entries in the constructor and destructor tables which are then 619 * tested for being not zero (which will always occur unless we're 620 * based from address zero). This causes an endless loop as __start 621 * is at zero. The solution used is to not relocate zero addresses. 622 * This has the negative side effect of not allowing a global data 623 * reference to be statically initialised to _stext (I've moved 624 * __start to address 4 so that is okay). 625 */ 626 if (rev > OLD_FLAT_VERSION) { 627 abi_ulong persistent = 0; 628 for (i = 0; i < relocs; i++) { 629 abi_ulong addr, relval; 630 631 /* Get the address of the pointer to be 632 relocated (of course, the address has to be 633 relocated first). */ 634 if (get_user_ual(relval, reloc + i * sizeof(abi_ulong))) 635 return -EFAULT; 636 relval = ntohl(relval); 637 if (flat_set_persistent(relval, &persistent)) 638 continue; 639 addr = flat_get_relocate_addr(relval); 640 rp = calc_reloc(addr, libinfo, id, 1); 641 if (rp == RELOC_FAILED) 642 return -ENOEXEC; 643 644 /* Get the pointer's value. */ 645 if (get_user_ual(addr, rp)) 646 return -EFAULT; 647 addr = flat_get_addr_from_rp(addr, relval, flags, &persistent); 648 if (addr != 0) { 649 /* 650 * Do the relocation. PIC relocs in the data section are 651 * already in target order 652 */ 653 if ((flags & FLAT_FLAG_GOTPIC) == 0) 654 addr = ntohl(addr); 655 addr = calc_reloc(addr, libinfo, id, 0); 656 if (addr == RELOC_FAILED) 657 return -ENOEXEC; 658 659 /* Write back the relocated pointer. */ 660 if (flat_put_addr_at_rp(rp, addr, relval)) 661 return -EFAULT; 662 } 663 } 664 } else { 665 for (i = 0; i < relocs; i++) { 666 abi_ulong relval; 667 if (get_user_ual(relval, reloc + i * sizeof(abi_ulong))) 668 return -EFAULT; 669 old_reloc(&libinfo[0], relval); 670 } 671 } 672 673 /* zero the BSS. */ 674 memset(g2h_untagged(datapos + data_len), 0, bss_len); 675 676 return 0; 677 } 678 679 680 /****************************************************************************/ 681 #ifdef CONFIG_BINFMT_SHARED_FLAT 682 683 /* 684 * Load a shared library into memory. The library gets its own data 685 * segment (including bss) but not argv/argc/environ. 686 */ 687 688 static int load_flat_shared_library(int id, struct lib_info *libs) 689 { 690 struct linux_binprm bprm; 691 int res; 692 char buf[16]; 693 694 /* Create the file name */ 695 sprintf(buf, "/lib/lib%d.so", id); 696 697 /* Open the file up */ 698 bprm.filename = buf; 699 bprm.file = open_exec(bprm.filename); 700 res = PTR_ERR(bprm.file); 701 if (IS_ERR(bprm.file)) 702 return res; 703 704 res = prepare_binprm(&bprm); 705 706 if (!is_error(res)) { 707 res = load_flat_file(&bprm, libs, id, NULL); 708 } 709 if (bprm.file) { 710 allow_write_access(bprm.file); 711 fput(bprm.file); 712 bprm.file = NULL; 713 } 714 return(res); 715 } 716 717 #endif /* CONFIG_BINFMT_SHARED_FLAT */ 718 719 int load_flt_binary(struct linux_binprm *bprm, struct image_info *info) 720 { 721 struct lib_info libinfo[MAX_SHARED_LIBS]; 722 abi_ulong p; 723 abi_ulong stack_len; 724 abi_ulong start_addr; 725 abi_ulong sp; 726 int res; 727 int i, j; 728 729 memset(libinfo, 0, sizeof(libinfo)); 730 /* 731 * We have to add the size of our arguments to our stack size 732 * otherwise it's too easy for users to create stack overflows 733 * by passing in a huge argument list. And yes, we have to be 734 * pedantic and include space for the argv/envp array as it may have 735 * a lot of entries. 736 */ 737 stack_len = 0; 738 for (i = 0; i < bprm->argc; ++i) { 739 /* the argv strings */ 740 stack_len += strlen(bprm->argv[i]); 741 } 742 for (i = 0; i < bprm->envc; ++i) { 743 /* the envp strings */ 744 stack_len += strlen(bprm->envp[i]); 745 } 746 stack_len += (bprm->argc + 1) * 4; /* the argv array */ 747 stack_len += (bprm->envc + 1) * 4; /* the envp array */ 748 749 750 res = load_flat_file(bprm, libinfo, 0, &stack_len); 751 if (is_error(res)) { 752 return res; 753 } 754 755 /* Update data segment pointers for all libraries */ 756 for (i=0; i<MAX_SHARED_LIBS; i++) { 757 if (libinfo[i].loaded) { 758 abi_ulong seg; 759 seg = libinfo[i].start_data; 760 for (j=0; j<MAX_SHARED_LIBS; j++) { 761 seg -= 4; 762 /* FIXME - handle put_user() failures */ 763 if (put_user_ual(libinfo[j].loaded 764 ? libinfo[j].start_data 765 : UNLOADED_LIB, 766 seg)) 767 return -EFAULT; 768 } 769 } 770 } 771 772 p = ((libinfo[0].start_brk + stack_len + 3) & ~3) - 4; 773 DBG_FLT("p=%x\n", (int)p); 774 775 /* Copy argv/envp. */ 776 p = copy_strings(p, bprm->envc, bprm->envp); 777 p = copy_strings(p, bprm->argc, bprm->argv); 778 /* Align stack. */ 779 sp = p & ~(abi_ulong)(sizeof(abi_ulong) - 1); 780 /* Enforce final stack alignment of 16 bytes. This is sufficient 781 for all current targets, and excess alignment is harmless. */ 782 stack_len = bprm->envc + bprm->argc + 2; 783 stack_len += flat_argvp_envp_on_stack() ? 2 : 0; /* argv, argp */ 784 stack_len += 1; /* argc */ 785 stack_len *= sizeof(abi_ulong); 786 sp -= (sp - stack_len) & 15; 787 sp = loader_build_argptr(bprm->envc, bprm->argc, sp, p, 788 flat_argvp_envp_on_stack()); 789 790 /* Fake some return addresses to ensure the call chain will 791 * initialise library in order for us. We are required to call 792 * lib 1 first, then 2, ... and finally the main program (id 0). 793 */ 794 start_addr = libinfo[0].entry; 795 796 #ifdef CONFIG_BINFMT_SHARED_FLAT 797 #error here 798 for (i = MAX_SHARED_LIBS-1; i>0; i--) { 799 if (libinfo[i].loaded) { 800 /* Push previous first to call address */ 801 --sp; 802 if (put_user_ual(start_addr, sp)) 803 return -EFAULT; 804 start_addr = libinfo[i].entry; 805 } 806 } 807 #endif 808 809 /* Stash our initial stack pointer into the mm structure */ 810 info->start_code = libinfo[0].start_code; 811 info->end_code = libinfo[0].start_code + libinfo[0].text_len; 812 info->start_data = libinfo[0].start_data; 813 info->end_data = libinfo[0].end_data; 814 info->brk = libinfo[0].start_brk; 815 info->start_stack = sp; 816 info->stack_limit = libinfo[0].start_brk; 817 info->entry = start_addr; 818 info->code_offset = info->start_code; 819 info->data_offset = info->start_data - libinfo[0].text_len; 820 821 DBG_FLT("start_thread(entry=0x%x, start_stack=0x%x)\n", 822 (int)info->entry, (int)info->start_stack); 823 824 return 0; 825 } 826