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 "flat.h" 40 #include "target_flat.h" 41 42 //#define DEBUG 43 44 #ifdef DEBUG 45 #define DBG_FLT(...) printf(__VA_ARGS__) 46 #else 47 #define DBG_FLT(...) 48 #endif 49 50 #define RELOC_FAILED 0xff00ff01 /* Relocation incorrect somewhere */ 51 #define UNLOADED_LIB 0x7ff000ff /* Placeholder for unused library */ 52 53 struct lib_info { 54 abi_ulong start_code; /* Start of text segment */ 55 abi_ulong start_data; /* Start of data segment */ 56 abi_ulong end_data; /* Start of bss section */ 57 abi_ulong start_brk; /* End of data segment */ 58 abi_ulong text_len; /* Length of text segment */ 59 abi_ulong entry; /* Start address for this module */ 60 abi_ulong build_date; /* When this one was compiled */ 61 short loaded; /* Has this library been loaded? */ 62 }; 63 64 #ifdef CONFIG_BINFMT_SHARED_FLAT 65 static int load_flat_shared_library(int id, struct lib_info *p); 66 #endif 67 68 struct linux_binprm; 69 70 /****************************************************************************/ 71 /* 72 * create_flat_tables() parses the env- and arg-strings in new user 73 * memory and creates the pointer tables from them, and puts their 74 * addresses on the "stack", returning the new stack pointer value. 75 */ 76 77 /* Push a block of strings onto the guest stack. */ 78 static abi_ulong copy_strings(abi_ulong p, int n, char **s) 79 { 80 int len; 81 82 while (n-- > 0) { 83 len = strlen(s[n]) + 1; 84 p -= len; 85 memcpy_to_target(p, s[n], len); 86 } 87 88 return p; 89 } 90 91 static int target_pread(int fd, abi_ulong ptr, abi_ulong len, 92 abi_ulong offset) 93 { 94 void *buf; 95 int ret; 96 97 buf = lock_user(VERIFY_WRITE, ptr, len, 0); 98 if (!buf) { 99 return -EFAULT; 100 } 101 ret = pread(fd, buf, len, offset); 102 if (ret < 0) { 103 ret = -errno; 104 } 105 unlock_user(buf, ptr, len); 106 return ret; 107 } 108 /****************************************************************************/ 109 110 #ifdef CONFIG_BINFMT_ZFLAT 111 112 #include <linux/zlib.h> 113 114 #define LBUFSIZE 4000 115 116 /* gzip flag byte */ 117 #define ASCII_FLAG 0x01 /* bit 0 set: file probably ASCII text */ 118 #define CONTINUATION 0x02 /* bit 1 set: continuation of multi-part gzip file */ 119 #define EXTRA_FIELD 0x04 /* bit 2 set: extra field present */ 120 #define ORIG_NAME 0x08 /* bit 3 set: original file name present */ 121 #define COMMENT 0x10 /* bit 4 set: file comment present */ 122 #define ENCRYPTED 0x20 /* bit 5 set: file is encrypted */ 123 #define RESERVED 0xC0 /* bit 6,7: reserved */ 124 125 static int decompress_exec( 126 struct linux_binprm *bprm, 127 unsigned long offset, 128 char *dst, 129 long len, 130 int fd) 131 { 132 unsigned char *buf; 133 z_stream strm; 134 loff_t fpos; 135 int ret, retval; 136 137 DBG_FLT("decompress_exec(offset=%x,buf=%x,len=%x)\n",(int)offset, (int)dst, (int)len); 138 139 memset(&strm, 0, sizeof(strm)); 140 strm.workspace = kmalloc(zlib_inflate_workspacesize(), GFP_KERNEL); 141 if (strm.workspace == NULL) { 142 DBG_FLT("binfmt_flat: no memory for decompress workspace\n"); 143 return -ENOMEM; 144 } 145 buf = kmalloc(LBUFSIZE, GFP_KERNEL); 146 if (buf == NULL) { 147 DBG_FLT("binfmt_flat: no memory for read buffer\n"); 148 retval = -ENOMEM; 149 goto out_free; 150 } 151 152 /* Read in first chunk of data and parse gzip header. */ 153 fpos = offset; 154 ret = bprm->file->f_op->read(bprm->file, buf, LBUFSIZE, &fpos); 155 156 strm.next_in = buf; 157 strm.avail_in = ret; 158 strm.total_in = 0; 159 160 retval = -ENOEXEC; 161 162 /* Check minimum size -- gzip header */ 163 if (ret < 10) { 164 DBG_FLT("binfmt_flat: file too small?\n"); 165 goto out_free_buf; 166 } 167 168 /* Check gzip magic number */ 169 if ((buf[0] != 037) || ((buf[1] != 0213) && (buf[1] != 0236))) { 170 DBG_FLT("binfmt_flat: unknown compression magic?\n"); 171 goto out_free_buf; 172 } 173 174 /* Check gzip method */ 175 if (buf[2] != 8) { 176 DBG_FLT("binfmt_flat: unknown compression method?\n"); 177 goto out_free_buf; 178 } 179 /* Check gzip flags */ 180 if ((buf[3] & ENCRYPTED) || (buf[3] & CONTINUATION) || 181 (buf[3] & RESERVED)) { 182 DBG_FLT("binfmt_flat: unknown flags?\n"); 183 goto out_free_buf; 184 } 185 186 ret = 10; 187 if (buf[3] & EXTRA_FIELD) { 188 ret += 2 + buf[10] + (buf[11] << 8); 189 if (unlikely(LBUFSIZE == ret)) { 190 DBG_FLT("binfmt_flat: buffer overflow (EXTRA)?\n"); 191 goto out_free_buf; 192 } 193 } 194 if (buf[3] & ORIG_NAME) { 195 for (; ret < LBUFSIZE && (buf[ret] != 0); ret++) 196 ; 197 if (unlikely(LBUFSIZE == ret)) { 198 DBG_FLT("binfmt_flat: buffer overflow (ORIG_NAME)?\n"); 199 goto out_free_buf; 200 } 201 } 202 if (buf[3] & COMMENT) { 203 for (; ret < LBUFSIZE && (buf[ret] != 0); ret++) 204 ; 205 if (unlikely(LBUFSIZE == ret)) { 206 DBG_FLT("binfmt_flat: buffer overflow (COMMENT)?\n"); 207 goto out_free_buf; 208 } 209 } 210 211 strm.next_in += ret; 212 strm.avail_in -= ret; 213 214 strm.next_out = dst; 215 strm.avail_out = len; 216 strm.total_out = 0; 217 218 if (zlib_inflateInit2(&strm, -MAX_WBITS) != Z_OK) { 219 DBG_FLT("binfmt_flat: zlib init failed?\n"); 220 goto out_free_buf; 221 } 222 223 while ((ret = zlib_inflate(&strm, Z_NO_FLUSH)) == Z_OK) { 224 ret = bprm->file->f_op->read(bprm->file, buf, LBUFSIZE, &fpos); 225 if (ret <= 0) 226 break; 227 if (ret >= (unsigned long) -4096) 228 break; 229 len -= ret; 230 231 strm.next_in = buf; 232 strm.avail_in = ret; 233 strm.total_in = 0; 234 } 235 236 if (ret < 0) { 237 DBG_FLT("binfmt_flat: decompression failed (%d), %s\n", 238 ret, strm.msg); 239 goto out_zlib; 240 } 241 242 retval = 0; 243 out_zlib: 244 zlib_inflateEnd(&strm); 245 out_free_buf: 246 kfree(buf); 247 out_free: 248 kfree(strm.workspace); 249 out: 250 return retval; 251 } 252 253 #endif /* CONFIG_BINFMT_ZFLAT */ 254 255 /****************************************************************************/ 256 257 static abi_ulong 258 calc_reloc(abi_ulong r, struct lib_info *p, int curid, int internalp) 259 { 260 abi_ulong addr; 261 int id; 262 abi_ulong start_brk; 263 abi_ulong start_data; 264 abi_ulong text_len; 265 abi_ulong start_code; 266 267 #ifdef CONFIG_BINFMT_SHARED_FLAT 268 #error needs checking 269 if (r == 0) 270 id = curid; /* Relocs of 0 are always self referring */ 271 else { 272 id = (r >> 24) & 0xff; /* Find ID for this reloc */ 273 r &= 0x00ffffff; /* Trim ID off here */ 274 } 275 if (id >= MAX_SHARED_LIBS) { 276 fprintf(stderr, "BINFMT_FLAT: reference 0x%x to shared library %d\n", 277 (unsigned) r, id); 278 goto failed; 279 } 280 if (curid != id) { 281 if (internalp) { 282 fprintf(stderr, "BINFMT_FLAT: reloc address 0x%x not " 283 "in same module (%d != %d)\n", 284 (unsigned) r, curid, id); 285 goto failed; 286 } else if ( ! p[id].loaded && 287 load_flat_shared_library(id, p) > (unsigned long) -4096) { 288 fprintf(stderr, "BINFMT_FLAT: failed to load library %d\n", id); 289 goto failed; 290 } 291 /* Check versioning information (i.e. time stamps) */ 292 if (p[id].build_date && p[curid].build_date 293 && p[curid].build_date < p[id].build_date) { 294 fprintf(stderr, "BINFMT_FLAT: library %d is younger than %d\n", 295 id, curid); 296 goto failed; 297 } 298 } 299 #else 300 id = 0; 301 #endif 302 303 start_brk = p[id].start_brk; 304 start_data = p[id].start_data; 305 start_code = p[id].start_code; 306 text_len = p[id].text_len; 307 308 if (!flat_reloc_valid(r, start_brk - start_data + text_len)) { 309 fprintf(stderr, "BINFMT_FLAT: reloc outside program 0x%x " 310 "(0 - 0x%x/0x%x)\n", 311 (int) r,(int)(start_brk-start_code),(int)text_len); 312 goto failed; 313 } 314 315 if (r < text_len) /* In text segment */ 316 addr = r + start_code; 317 else /* In data segment */ 318 addr = r - text_len + start_data; 319 320 /* Range checked already above so doing the range tests is redundant...*/ 321 return(addr); 322 323 failed: 324 abort(); 325 return RELOC_FAILED; 326 } 327 328 /****************************************************************************/ 329 330 /* ??? This does not handle endianness correctly. */ 331 static void old_reloc(struct lib_info *libinfo, uint32_t rl) 332 { 333 #ifdef DEBUG 334 const char *segment[] = { "TEXT", "DATA", "BSS", "*UNKNOWN*" }; 335 #endif 336 uint32_t *ptr; 337 uint32_t offset; 338 int reloc_type; 339 340 offset = rl & 0x3fffffff; 341 reloc_type = rl >> 30; 342 /* ??? How to handle this? */ 343 #if defined(CONFIG_COLDFIRE) 344 ptr = (uint32_t *) ((unsigned long) libinfo->start_code + offset); 345 #else 346 ptr = (uint32_t *) ((unsigned long) libinfo->start_data + offset); 347 #endif 348 349 #ifdef DEBUG 350 fprintf(stderr, "Relocation of variable at DATASEG+%x " 351 "(address %p, currently %x) into segment %s\n", 352 offset, ptr, (int)*ptr, segment[reloc_type]); 353 #endif 354 355 switch (reloc_type) { 356 case OLD_FLAT_RELOC_TYPE_TEXT: 357 *ptr += libinfo->start_code; 358 break; 359 case OLD_FLAT_RELOC_TYPE_DATA: 360 *ptr += libinfo->start_data; 361 break; 362 case OLD_FLAT_RELOC_TYPE_BSS: 363 *ptr += libinfo->end_data; 364 break; 365 default: 366 fprintf(stderr, "BINFMT_FLAT: Unknown relocation type=%x\n", 367 reloc_type); 368 break; 369 } 370 DBG_FLT("Relocation became %x\n", (int)*ptr); 371 } 372 373 /****************************************************************************/ 374 375 static int load_flat_file(struct linux_binprm * bprm, 376 struct lib_info *libinfo, int id, abi_ulong *extra_stack) 377 { 378 struct flat_hdr * hdr; 379 abi_ulong textpos = 0, datapos = 0; 380 abi_long result; 381 abi_ulong realdatastart = 0; 382 abi_ulong text_len, data_len, bss_len, stack_len, flags; 383 abi_ulong extra; 384 abi_ulong reloc = 0, rp; 385 int i, rev, relocs = 0; 386 abi_ulong fpos; 387 abi_ulong start_code; 388 abi_ulong indx_len; 389 390 hdr = ((struct flat_hdr *) bprm->buf); /* exec-header */ 391 392 text_len = ntohl(hdr->data_start); 393 data_len = ntohl(hdr->data_end) - ntohl(hdr->data_start); 394 bss_len = ntohl(hdr->bss_end) - ntohl(hdr->data_end); 395 stack_len = ntohl(hdr->stack_size); 396 if (extra_stack) { 397 stack_len += *extra_stack; 398 *extra_stack = stack_len; 399 } 400 relocs = ntohl(hdr->reloc_count); 401 flags = ntohl(hdr->flags); 402 rev = ntohl(hdr->rev); 403 404 DBG_FLT("BINFMT_FLAT: Loading file: %s\n", bprm->filename); 405 406 if (rev != FLAT_VERSION && rev != OLD_FLAT_VERSION) { 407 fprintf(stderr, "BINFMT_FLAT: bad magic/rev (0x%x, need 0x%x)\n", 408 rev, (int) FLAT_VERSION); 409 return -ENOEXEC; 410 } 411 412 /* Don't allow old format executables to use shared libraries */ 413 if (rev == OLD_FLAT_VERSION && id != 0) { 414 fprintf(stderr, "BINFMT_FLAT: shared libraries are not available\n"); 415 return -ENOEXEC; 416 } 417 418 /* 419 * fix up the flags for the older format, there were all kinds 420 * of endian hacks, this only works for the simple cases 421 */ 422 if (rev == OLD_FLAT_VERSION && flat_old_ram_flag(flags)) 423 flags = FLAT_FLAG_RAM; 424 425 #ifndef CONFIG_BINFMT_ZFLAT 426 if (flags & (FLAT_FLAG_GZIP|FLAT_FLAG_GZDATA)) { 427 fprintf(stderr, "Support for ZFLAT executables is not enabled\n"); 428 return -ENOEXEC; 429 } 430 #endif 431 432 /* 433 * calculate the extra space we need to map in 434 */ 435 extra = relocs * sizeof(abi_ulong); 436 if (extra < bss_len + stack_len) 437 extra = bss_len + stack_len; 438 439 /* Add space for library base pointers. Make sure this does not 440 misalign the doesn't misalign the data segment. */ 441 indx_len = MAX_SHARED_LIBS * sizeof(abi_ulong); 442 indx_len = (indx_len + 15) & ~(abi_ulong)15; 443 444 /* 445 * there are a couple of cases here, the separate code/data 446 * case, and then the fully copied to RAM case which lumps 447 * it all together. 448 */ 449 if ((flags & (FLAT_FLAG_RAM|FLAT_FLAG_GZIP)) == 0) { 450 /* 451 * this should give us a ROM ptr, but if it doesn't we don't 452 * really care 453 */ 454 DBG_FLT("BINFMT_FLAT: ROM mapping of file (we hope)\n"); 455 456 textpos = target_mmap(0, text_len, PROT_READ|PROT_EXEC, 457 MAP_PRIVATE, bprm->fd, 0); 458 if (textpos == -1) { 459 fprintf(stderr, "Unable to mmap process text\n"); 460 return -1; 461 } 462 463 realdatastart = target_mmap(0, data_len + extra + indx_len, 464 PROT_READ|PROT_WRITE|PROT_EXEC, 465 MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); 466 467 if (realdatastart == -1) { 468 fprintf(stderr, "Unable to allocate RAM for process data\n"); 469 return realdatastart; 470 } 471 datapos = realdatastart + indx_len; 472 473 DBG_FLT("BINFMT_FLAT: Allocated data+bss+stack (%d bytes): %x\n", 474 (int)(data_len + bss_len + stack_len), (int)datapos); 475 476 fpos = ntohl(hdr->data_start); 477 #ifdef CONFIG_BINFMT_ZFLAT 478 if (flags & FLAT_FLAG_GZDATA) { 479 result = decompress_exec(bprm, fpos, (char *) datapos, 480 data_len + (relocs * sizeof(abi_ulong))) 481 } else 482 #endif 483 { 484 result = target_pread(bprm->fd, datapos, 485 data_len + (relocs * sizeof(abi_ulong)), 486 fpos); 487 } 488 if (result < 0) { 489 fprintf(stderr, "Unable to read data+bss\n"); 490 return result; 491 } 492 493 reloc = datapos + (ntohl(hdr->reloc_start) - text_len); 494 495 } else { 496 497 textpos = target_mmap(0, text_len + data_len + extra + indx_len, 498 PROT_READ | PROT_EXEC | PROT_WRITE, 499 MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); 500 if (textpos == -1 ) { 501 fprintf(stderr, "Unable to allocate RAM for process text/data\n"); 502 return -1; 503 } 504 505 realdatastart = textpos + ntohl(hdr->data_start); 506 datapos = realdatastart + indx_len; 507 reloc = (textpos + ntohl(hdr->reloc_start) + indx_len); 508 509 #ifdef CONFIG_BINFMT_ZFLAT 510 #error code needs checking 511 /* 512 * load it all in and treat it like a RAM load from now on 513 */ 514 if (flags & FLAT_FLAG_GZIP) { 515 result = decompress_exec(bprm, sizeof (struct flat_hdr), 516 (((char *) textpos) + sizeof (struct flat_hdr)), 517 (text_len + data_len + (relocs * sizeof(unsigned long)) 518 - sizeof (struct flat_hdr)), 519 0); 520 memmove((void *) datapos, (void *) realdatastart, 521 data_len + (relocs * sizeof(unsigned long))); 522 } else if (flags & FLAT_FLAG_GZDATA) { 523 fpos = 0; 524 result = bprm->file->f_op->read(bprm->file, 525 (char *) textpos, text_len, &fpos); 526 if (result < (unsigned long) -4096) 527 result = decompress_exec(bprm, text_len, (char *) datapos, 528 data_len + (relocs * sizeof(unsigned long)), 0); 529 } 530 else 531 #endif 532 { 533 result = target_pread(bprm->fd, textpos, 534 text_len, 0); 535 if (result >= 0) { 536 result = target_pread(bprm->fd, datapos, 537 data_len + (relocs * sizeof(abi_ulong)), 538 ntohl(hdr->data_start)); 539 } 540 } 541 if (result < 0) { 542 fprintf(stderr, "Unable to read code+data+bss\n"); 543 return result; 544 } 545 } 546 547 DBG_FLT("Mapping is 0x%x, Entry point is 0x%x, data_start is 0x%x\n", 548 (int)textpos, 0x00ffffff&ntohl(hdr->entry), 549 ntohl(hdr->data_start)); 550 551 /* The main program needs a little extra setup in the task structure */ 552 start_code = textpos + sizeof (struct flat_hdr); 553 554 DBG_FLT("%s %s: TEXT=%x-%x DATA=%x-%x BSS=%x-%x\n", 555 id ? "Lib" : "Load", bprm->filename, 556 (int) start_code, (int) (textpos + text_len), 557 (int) datapos, 558 (int) (datapos + data_len), 559 (int) (datapos + data_len), 560 (int) (((datapos + data_len + bss_len) + 3) & ~3)); 561 562 text_len -= sizeof(struct flat_hdr); /* the real code len */ 563 564 /* Store the current module values into the global library structure */ 565 libinfo[id].start_code = start_code; 566 libinfo[id].start_data = datapos; 567 libinfo[id].end_data = datapos + data_len; 568 libinfo[id].start_brk = datapos + data_len + bss_len; 569 libinfo[id].text_len = text_len; 570 libinfo[id].loaded = 1; 571 libinfo[id].entry = (0x00ffffff & ntohl(hdr->entry)) + textpos; 572 libinfo[id].build_date = ntohl(hdr->build_date); 573 574 /* 575 * We just load the allocations into some temporary memory to 576 * help simplify all this mumbo jumbo 577 * 578 * We've got two different sections of relocation entries. 579 * The first is the GOT which resides at the beginning of the data segment 580 * and is terminated with a -1. This one can be relocated in place. 581 * The second is the extra relocation entries tacked after the image's 582 * data segment. These require a little more processing as the entry is 583 * really an offset into the image which contains an offset into the 584 * image. 585 */ 586 if (flags & FLAT_FLAG_GOTPIC) { 587 rp = datapos; 588 while (1) { 589 abi_ulong addr; 590 if (get_user_ual(addr, rp)) 591 return -EFAULT; 592 if (addr == -1) 593 break; 594 if (addr) { 595 addr = calc_reloc(addr, libinfo, id, 0); 596 if (addr == RELOC_FAILED) 597 return -ENOEXEC; 598 if (put_user_ual(addr, rp)) 599 return -EFAULT; 600 } 601 rp += sizeof(abi_ulong); 602 } 603 } 604 605 /* 606 * Now run through the relocation entries. 607 * We've got to be careful here as C++ produces relocatable zero 608 * entries in the constructor and destructor tables which are then 609 * tested for being not zero (which will always occur unless we're 610 * based from address zero). This causes an endless loop as __start 611 * is at zero. The solution used is to not relocate zero addresses. 612 * This has the negative side effect of not allowing a global data 613 * reference to be statically initialised to _stext (I've moved 614 * __start to address 4 so that is okay). 615 */ 616 if (rev > OLD_FLAT_VERSION) { 617 abi_ulong persistent = 0; 618 for (i = 0; i < relocs; i++) { 619 abi_ulong addr, relval; 620 621 /* Get the address of the pointer to be 622 relocated (of course, the address has to be 623 relocated first). */ 624 if (get_user_ual(relval, reloc + i * sizeof(abi_ulong))) 625 return -EFAULT; 626 relval = ntohl(relval); 627 if (flat_set_persistent(relval, &persistent)) 628 continue; 629 addr = flat_get_relocate_addr(relval); 630 rp = calc_reloc(addr, libinfo, id, 1); 631 if (rp == RELOC_FAILED) 632 return -ENOEXEC; 633 634 /* Get the pointer's value. */ 635 if (get_user_ual(addr, rp)) 636 return -EFAULT; 637 addr = flat_get_addr_from_rp(addr, relval, flags, &persistent); 638 if (addr != 0) { 639 /* 640 * Do the relocation. PIC relocs in the data section are 641 * already in target order 642 */ 643 if ((flags & FLAT_FLAG_GOTPIC) == 0) 644 addr = ntohl(addr); 645 addr = calc_reloc(addr, libinfo, id, 0); 646 if (addr == RELOC_FAILED) 647 return -ENOEXEC; 648 649 /* Write back the relocated pointer. */ 650 if (flat_put_addr_at_rp(rp, addr, relval)) 651 return -EFAULT; 652 } 653 } 654 } else { 655 for (i = 0; i < relocs; i++) { 656 abi_ulong relval; 657 if (get_user_ual(relval, reloc + i * sizeof(abi_ulong))) 658 return -EFAULT; 659 old_reloc(&libinfo[0], relval); 660 } 661 } 662 663 /* zero the BSS. */ 664 memset(g2h(datapos + data_len), 0, bss_len); 665 666 return 0; 667 } 668 669 670 /****************************************************************************/ 671 #ifdef CONFIG_BINFMT_SHARED_FLAT 672 673 /* 674 * Load a shared library into memory. The library gets its own data 675 * segment (including bss) but not argv/argc/environ. 676 */ 677 678 static int load_flat_shared_library(int id, struct lib_info *libs) 679 { 680 struct linux_binprm bprm; 681 int res; 682 char buf[16]; 683 684 /* Create the file name */ 685 sprintf(buf, "/lib/lib%d.so", id); 686 687 /* Open the file up */ 688 bprm.filename = buf; 689 bprm.file = open_exec(bprm.filename); 690 res = PTR_ERR(bprm.file); 691 if (IS_ERR(bprm.file)) 692 return res; 693 694 res = prepare_binprm(&bprm); 695 696 if (res <= (unsigned long)-4096) 697 res = load_flat_file(&bprm, libs, id, NULL); 698 if (bprm.file) { 699 allow_write_access(bprm.file); 700 fput(bprm.file); 701 bprm.file = NULL; 702 } 703 return(res); 704 } 705 706 #endif /* CONFIG_BINFMT_SHARED_FLAT */ 707 708 int load_flt_binary(struct linux_binprm *bprm, struct image_info *info) 709 { 710 struct lib_info libinfo[MAX_SHARED_LIBS]; 711 abi_ulong p; 712 abi_ulong stack_len; 713 abi_ulong start_addr; 714 abi_ulong sp; 715 int res; 716 int i, j; 717 718 memset(libinfo, 0, sizeof(libinfo)); 719 /* 720 * We have to add the size of our arguments to our stack size 721 * otherwise it's too easy for users to create stack overflows 722 * by passing in a huge argument list. And yes, we have to be 723 * pedantic and include space for the argv/envp array as it may have 724 * a lot of entries. 725 */ 726 stack_len = 0; 727 for (i = 0; i < bprm->argc; ++i) { 728 /* the argv strings */ 729 stack_len += strlen(bprm->argv[i]); 730 } 731 for (i = 0; i < bprm->envc; ++i) { 732 /* the envp strings */ 733 stack_len += strlen(bprm->envp[i]); 734 } 735 stack_len += (bprm->argc + 1) * 4; /* the argv array */ 736 stack_len += (bprm->envc + 1) * 4; /* the envp array */ 737 738 739 res = load_flat_file(bprm, libinfo, 0, &stack_len); 740 if (res > (unsigned long)-4096) 741 return res; 742 743 /* Update data segment pointers for all libraries */ 744 for (i=0; i<MAX_SHARED_LIBS; i++) { 745 if (libinfo[i].loaded) { 746 abi_ulong p; 747 p = libinfo[i].start_data; 748 for (j=0; j<MAX_SHARED_LIBS; j++) { 749 p -= 4; 750 /* FIXME - handle put_user() failures */ 751 if (put_user_ual(libinfo[j].loaded 752 ? libinfo[j].start_data 753 : UNLOADED_LIB, 754 p)) 755 return -EFAULT; 756 } 757 } 758 } 759 760 p = ((libinfo[0].start_brk + stack_len + 3) & ~3) - 4; 761 DBG_FLT("p=%x\n", (int)p); 762 763 /* Copy argv/envp. */ 764 p = copy_strings(p, bprm->envc, bprm->envp); 765 p = copy_strings(p, bprm->argc, bprm->argv); 766 /* Align stack. */ 767 sp = p & ~(abi_ulong)(sizeof(abi_ulong) - 1); 768 /* Enforce final stack alignment of 16 bytes. This is sufficient 769 for all current targets, and excess alignment is harmless. */ 770 stack_len = bprm->envc + bprm->argc + 2; 771 stack_len += 3; /* argc, arvg, argp */ 772 stack_len *= sizeof(abi_ulong); 773 if ((sp + stack_len) & 15) 774 sp -= 16 - ((sp + stack_len) & 15); 775 sp = loader_build_argptr(bprm->envc, bprm->argc, sp, p, 776 flat_argvp_envp_on_stack()); 777 778 /* Fake some return addresses to ensure the call chain will 779 * initialise library in order for us. We are required to call 780 * lib 1 first, then 2, ... and finally the main program (id 0). 781 */ 782 start_addr = libinfo[0].entry; 783 784 #ifdef CONFIG_BINFMT_SHARED_FLAT 785 #error here 786 for (i = MAX_SHARED_LIBS-1; i>0; i--) { 787 if (libinfo[i].loaded) { 788 /* Push previos first to call address */ 789 --sp; 790 if (put_user_ual(start_addr, sp)) 791 return -EFAULT; 792 start_addr = libinfo[i].entry; 793 } 794 } 795 #endif 796 797 /* Stash our initial stack pointer into the mm structure */ 798 info->start_code = libinfo[0].start_code; 799 info->end_code = libinfo[0].start_code = libinfo[0].text_len; 800 info->start_data = libinfo[0].start_data; 801 info->end_data = libinfo[0].end_data; 802 info->start_brk = libinfo[0].start_brk; 803 info->start_stack = sp; 804 info->stack_limit = libinfo[0].start_brk; 805 info->entry = start_addr; 806 info->code_offset = info->start_code; 807 info->data_offset = info->start_data - libinfo[0].text_len; 808 809 DBG_FLT("start_thread(entry=0x%x, start_stack=0x%x)\n", 810 (int)info->entry, (int)info->start_stack); 811 812 return 0; 813 } 814