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, write to the Free Software 17 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. 18 * 19 * Copyright (C) 2006 CodeSourcery. 20 * Copyright (C) 2000-2003 David McCullough <davidm@snapgear.com> 21 * Copyright (C) 2002 Greg Ungerer <gerg@snapgear.com> 22 * Copyright (C) 2002 SnapGear, by Paul Dale <pauli@snapgear.com> 23 * Copyright (C) 2000, 2001 Lineo, by David McCullough <davidm@lineo.com> 24 * based heavily on: 25 * 26 * linux/fs/binfmt_aout.c: 27 * Copyright (C) 1991, 1992, 1996 Linus Torvalds 28 * linux/fs/binfmt_flat.c for 2.0 kernel 29 * Copyright (C) 1998 Kenneth Albanowski <kjahds@kjahds.com> 30 * JAN/99 -- coded full program relocation (gerg@snapgear.com) 31 */ 32 33 /* ??? ZFLAT and shared library support is currently disabled. */ 34 35 /****************************************************************************/ 36 37 #include <stdio.h> 38 #include <stdlib.h> 39 #include <errno.h> 40 #include <sys/mman.h> 41 #include <unistd.h> 42 43 #include "qemu.h" 44 #include "flat.h" 45 46 //#define DEBUG 47 48 #ifdef DEBUG 49 #define DBG_FLT(a...) printf(a) 50 #else 51 #define DBG_FLT(a...) 52 #endif 53 54 #define flat_reloc_valid(reloc, size) ((reloc) <= (size)) 55 #define flat_old_ram_flag(flag) (flag) 56 #ifdef TARGET_WORDS_BIGENDIAN 57 #define flat_get_relocate_addr(relval) (relval) 58 #else 59 #define flat_get_relocate_addr(relval) bswap32(relval) 60 #endif 61 62 #define RELOC_FAILED 0xff00ff01 /* Relocation incorrect somewhere */ 63 #define UNLOADED_LIB 0x7ff000ff /* Placeholder for unused library */ 64 65 struct lib_info { 66 target_ulong start_code; /* Start of text segment */ 67 target_ulong start_data; /* Start of data segment */ 68 target_ulong end_data; /* Start of bss section */ 69 target_ulong start_brk; /* End of data segment */ 70 target_ulong text_len; /* Length of text segment */ 71 target_ulong entry; /* Start address for this module */ 72 target_ulong build_date; /* When this one was compiled */ 73 short loaded; /* Has this library been loaded? */ 74 }; 75 76 #ifdef CONFIG_BINFMT_SHARED_FLAT 77 static int load_flat_shared_library(int id, struct lib_info *p); 78 #endif 79 80 struct linux_binprm; 81 82 #define ntohl(x) be32_to_cpu(x) 83 84 /****************************************************************************/ 85 /* 86 * create_flat_tables() parses the env- and arg-strings in new user 87 * memory and creates the pointer tables from them, and puts their 88 * addresses on the "stack", returning the new stack pointer value. 89 */ 90 91 /* Push a block of strings onto the guest stack. */ 92 static target_ulong copy_strings(target_ulong p, int n, char **s) 93 { 94 int len; 95 96 while (n-- > 0) { 97 len = strlen(s[n]) + 1; 98 p -= len; 99 memcpy_to_target(p, s[n], len); 100 } 101 102 return p; 103 } 104 105 int target_pread(int fd, target_ulong ptr, target_ulong len, 106 target_ulong offset) 107 { 108 void *buf; 109 int ret; 110 111 buf = lock_user(ptr, len, 0); 112 ret = pread(fd, buf, len, offset); 113 unlock_user(buf, ptr, len); 114 return ret; 115 } 116 /****************************************************************************/ 117 118 #ifdef CONFIG_BINFMT_ZFLAT 119 120 #include <linux/zlib.h> 121 122 #define LBUFSIZE 4000 123 124 /* gzip flag byte */ 125 #define ASCII_FLAG 0x01 /* bit 0 set: file probably ASCII text */ 126 #define CONTINUATION 0x02 /* bit 1 set: continuation of multi-part gzip file */ 127 #define EXTRA_FIELD 0x04 /* bit 2 set: extra field present */ 128 #define ORIG_NAME 0x08 /* bit 3 set: original file name present */ 129 #define COMMENT 0x10 /* bit 4 set: file comment present */ 130 #define ENCRYPTED 0x20 /* bit 5 set: file is encrypted */ 131 #define RESERVED 0xC0 /* bit 6,7: reserved */ 132 133 static int decompress_exec( 134 struct linux_binprm *bprm, 135 unsigned long offset, 136 char *dst, 137 long len, 138 int fd) 139 { 140 unsigned char *buf; 141 z_stream strm; 142 loff_t fpos; 143 int ret, retval; 144 145 DBG_FLT("decompress_exec(offset=%x,buf=%x,len=%x)\n",(int)offset, (int)dst, (int)len); 146 147 memset(&strm, 0, sizeof(strm)); 148 strm.workspace = kmalloc(zlib_inflate_workspacesize(), GFP_KERNEL); 149 if (strm.workspace == NULL) { 150 DBG_FLT("binfmt_flat: no memory for decompress workspace\n"); 151 return -ENOMEM; 152 } 153 buf = kmalloc(LBUFSIZE, GFP_KERNEL); 154 if (buf == NULL) { 155 DBG_FLT("binfmt_flat: no memory for read buffer\n"); 156 retval = -ENOMEM; 157 goto out_free; 158 } 159 160 /* Read in first chunk of data and parse gzip header. */ 161 fpos = offset; 162 ret = bprm->file->f_op->read(bprm->file, buf, LBUFSIZE, &fpos); 163 164 strm.next_in = buf; 165 strm.avail_in = ret; 166 strm.total_in = 0; 167 168 retval = -ENOEXEC; 169 170 /* Check minimum size -- gzip header */ 171 if (ret < 10) { 172 DBG_FLT("binfmt_flat: file too small?\n"); 173 goto out_free_buf; 174 } 175 176 /* Check gzip magic number */ 177 if ((buf[0] != 037) || ((buf[1] != 0213) && (buf[1] != 0236))) { 178 DBG_FLT("binfmt_flat: unknown compression magic?\n"); 179 goto out_free_buf; 180 } 181 182 /* Check gzip method */ 183 if (buf[2] != 8) { 184 DBG_FLT("binfmt_flat: unknown compression method?\n"); 185 goto out_free_buf; 186 } 187 /* Check gzip flags */ 188 if ((buf[3] & ENCRYPTED) || (buf[3] & CONTINUATION) || 189 (buf[3] & RESERVED)) { 190 DBG_FLT("binfmt_flat: unknown flags?\n"); 191 goto out_free_buf; 192 } 193 194 ret = 10; 195 if (buf[3] & EXTRA_FIELD) { 196 ret += 2 + buf[10] + (buf[11] << 8); 197 if (unlikely(LBUFSIZE == ret)) { 198 DBG_FLT("binfmt_flat: buffer overflow (EXTRA)?\n"); 199 goto out_free_buf; 200 } 201 } 202 if (buf[3] & ORIG_NAME) { 203 for (; ret < LBUFSIZE && (buf[ret] != 0); ret++) 204 ; 205 if (unlikely(LBUFSIZE == ret)) { 206 DBG_FLT("binfmt_flat: buffer overflow (ORIG_NAME)?\n"); 207 goto out_free_buf; 208 } 209 } 210 if (buf[3] & COMMENT) { 211 for (; ret < LBUFSIZE && (buf[ret] != 0); ret++) 212 ; 213 if (unlikely(LBUFSIZE == ret)) { 214 DBG_FLT("binfmt_flat: buffer overflow (COMMENT)?\n"); 215 goto out_free_buf; 216 } 217 } 218 219 strm.next_in += ret; 220 strm.avail_in -= ret; 221 222 strm.next_out = dst; 223 strm.avail_out = len; 224 strm.total_out = 0; 225 226 if (zlib_inflateInit2(&strm, -MAX_WBITS) != Z_OK) { 227 DBG_FLT("binfmt_flat: zlib init failed?\n"); 228 goto out_free_buf; 229 } 230 231 while ((ret = zlib_inflate(&strm, Z_NO_FLUSH)) == Z_OK) { 232 ret = bprm->file->f_op->read(bprm->file, buf, LBUFSIZE, &fpos); 233 if (ret <= 0) 234 break; 235 if (ret >= (unsigned long) -4096) 236 break; 237 len -= ret; 238 239 strm.next_in = buf; 240 strm.avail_in = ret; 241 strm.total_in = 0; 242 } 243 244 if (ret < 0) { 245 DBG_FLT("binfmt_flat: decompression failed (%d), %s\n", 246 ret, strm.msg); 247 goto out_zlib; 248 } 249 250 retval = 0; 251 out_zlib: 252 zlib_inflateEnd(&strm); 253 out_free_buf: 254 kfree(buf); 255 out_free: 256 kfree(strm.workspace); 257 out: 258 return retval; 259 } 260 261 #endif /* CONFIG_BINFMT_ZFLAT */ 262 263 /****************************************************************************/ 264 265 static target_ulong 266 calc_reloc(target_ulong r, struct lib_info *p, int curid, int internalp) 267 { 268 target_ulong addr; 269 int id; 270 target_ulong start_brk; 271 target_ulong start_data; 272 target_ulong text_len; 273 target_ulong start_code; 274 275 #ifdef CONFIG_BINFMT_SHARED_FLAT 276 #error needs checking 277 if (r == 0) 278 id = curid; /* Relocs of 0 are always self referring */ 279 else { 280 id = (r >> 24) & 0xff; /* Find ID for this reloc */ 281 r &= 0x00ffffff; /* Trim ID off here */ 282 } 283 if (id >= MAX_SHARED_LIBS) { 284 fprintf(stderr, "BINFMT_FLAT: reference 0x%x to shared library %d\n", 285 (unsigned) r, id); 286 goto failed; 287 } 288 if (curid != id) { 289 if (internalp) { 290 fprintf(stderr, "BINFMT_FLAT: reloc address 0x%x not " 291 "in same module (%d != %d)\n", 292 (unsigned) r, curid, id); 293 goto failed; 294 } else if ( ! p[id].loaded && 295 load_flat_shared_library(id, p) > (unsigned long) -4096) { 296 fprintf(stderr, "BINFMT_FLAT: failed to load library %d\n", id); 297 goto failed; 298 } 299 /* Check versioning information (i.e. time stamps) */ 300 if (p[id].build_date && p[curid].build_date 301 && p[curid].build_date < p[id].build_date) { 302 fprintf(stderr, "BINFMT_FLAT: library %d is younger than %d\n", 303 id, curid); 304 goto failed; 305 } 306 } 307 #else 308 id = 0; 309 #endif 310 311 start_brk = p[id].start_brk; 312 start_data = p[id].start_data; 313 start_code = p[id].start_code; 314 text_len = p[id].text_len; 315 316 if (!flat_reloc_valid(r, start_brk - start_data + text_len)) { 317 fprintf(stderr, "BINFMT_FLAT: reloc outside program 0x%x " 318 "(0 - 0x%x/0x%x)\n", 319 (int) r,(int)(start_brk-start_code),(int)text_len); 320 goto failed; 321 } 322 323 if (r < text_len) /* In text segment */ 324 addr = r + start_code; 325 else /* In data segment */ 326 addr = r - text_len + start_data; 327 328 /* Range checked already above so doing the range tests is redundant...*/ 329 return(addr); 330 331 failed: 332 abort(); 333 return RELOC_FAILED; 334 } 335 336 /****************************************************************************/ 337 338 /* ??? This does not handle endianness correctly. */ 339 void old_reloc(struct lib_info *libinfo, uint32_t rl) 340 { 341 #ifdef DEBUG 342 char *segment[] = { "TEXT", "DATA", "BSS", "*UNKNOWN*" }; 343 #endif 344 uint32_t *ptr; 345 uint32_t offset; 346 int reloc_type; 347 348 offset = rl & 0x3fffffff; 349 reloc_type = rl >> 30; 350 /* ??? How to handle this? */ 351 #if defined(CONFIG_COLDFIRE) 352 ptr = (uint32_t *) (libinfo->start_code + offset); 353 #else 354 ptr = (uint32_t *) (libinfo->start_data + offset); 355 #endif 356 357 #ifdef DEBUG 358 fprintf(stderr, "Relocation of variable at DATASEG+%x " 359 "(address %p, currently %x) into segment %s\n", 360 offset, ptr, (int)*ptr, segment[reloc_type]); 361 #endif 362 363 switch (reloc_type) { 364 case OLD_FLAT_RELOC_TYPE_TEXT: 365 *ptr += libinfo->start_code; 366 break; 367 case OLD_FLAT_RELOC_TYPE_DATA: 368 *ptr += libinfo->start_data; 369 break; 370 case OLD_FLAT_RELOC_TYPE_BSS: 371 *ptr += libinfo->end_data; 372 break; 373 default: 374 fprintf(stderr, "BINFMT_FLAT: Unknown relocation type=%x\n", 375 reloc_type); 376 break; 377 } 378 DBG_FLT("Relocation became %x\n", (int)*ptr); 379 } 380 381 /****************************************************************************/ 382 383 static int load_flat_file(struct linux_binprm * bprm, 384 struct lib_info *libinfo, int id, target_ulong *extra_stack) 385 { 386 struct flat_hdr * hdr; 387 target_ulong textpos = 0, datapos = 0, result; 388 target_ulong realdatastart = 0; 389 target_ulong text_len, data_len, bss_len, stack_len, flags; 390 target_ulong memp = 0; /* for finding the brk area */ 391 target_ulong extra; 392 target_ulong reloc = 0, rp; 393 int i, rev, relocs = 0; 394 target_ulong fpos; 395 target_ulong start_code, end_code; 396 target_ulong indx_len; 397 398 hdr = ((struct flat_hdr *) bprm->buf); /* exec-header */ 399 400 text_len = ntohl(hdr->data_start); 401 data_len = ntohl(hdr->data_end) - ntohl(hdr->data_start); 402 bss_len = ntohl(hdr->bss_end) - ntohl(hdr->data_end); 403 stack_len = ntohl(hdr->stack_size); 404 if (extra_stack) { 405 stack_len += *extra_stack; 406 *extra_stack = stack_len; 407 } 408 relocs = ntohl(hdr->reloc_count); 409 flags = ntohl(hdr->flags); 410 rev = ntohl(hdr->rev); 411 412 DBG_FLT("BINFMT_FLAT: Loading file: %s\n", bprm->filename); 413 414 if (rev != FLAT_VERSION && rev != OLD_FLAT_VERSION) { 415 fprintf(stderr, "BINFMT_FLAT: bad magic/rev (0x%x, need 0x%x)\n", 416 rev, (int) FLAT_VERSION); 417 return -ENOEXEC; 418 } 419 420 /* Don't allow old format executables to use shared libraries */ 421 if (rev == OLD_FLAT_VERSION && id != 0) { 422 fprintf(stderr, "BINFMT_FLAT: shared libraries are not available\n"); 423 return -ENOEXEC; 424 } 425 426 /* 427 * fix up the flags for the older format, there were all kinds 428 * of endian hacks, this only works for the simple cases 429 */ 430 if (rev == OLD_FLAT_VERSION && flat_old_ram_flag(flags)) 431 flags = FLAT_FLAG_RAM; 432 433 #ifndef CONFIG_BINFMT_ZFLAT 434 if (flags & (FLAT_FLAG_GZIP|FLAT_FLAG_GZDATA)) { 435 fprintf(stderr, "Support for ZFLAT executables is not enabled\n"); 436 return -ENOEXEC; 437 } 438 #endif 439 440 /* 441 * calculate the extra space we need to map in 442 */ 443 extra = relocs * sizeof(target_ulong); 444 if (extra < bss_len + stack_len) 445 extra = bss_len + stack_len; 446 447 /* Add space for library base pointers. Make sure this does not 448 misalign the doesn't misalign the data segment. */ 449 indx_len = MAX_SHARED_LIBS * sizeof(target_ulong); 450 indx_len = (indx_len + 15) & ~(target_ulong)15; 451 452 /* 453 * there are a couple of cases here, the separate code/data 454 * case, and then the fully copied to RAM case which lumps 455 * it all together. 456 */ 457 if ((flags & (FLAT_FLAG_RAM|FLAT_FLAG_GZIP)) == 0) { 458 /* 459 * this should give us a ROM ptr, but if it doesn't we don't 460 * really care 461 */ 462 DBG_FLT("BINFMT_FLAT: ROM mapping of file (we hope)\n"); 463 464 textpos = target_mmap(0, text_len, PROT_READ|PROT_EXEC, 465 MAP_PRIVATE, bprm->fd, 0); 466 if (textpos == -1) { 467 fprintf(stderr, "Unable to mmap process text\n"); 468 return -1; 469 } 470 471 realdatastart = target_mmap(0, data_len + extra + indx_len, 472 PROT_READ|PROT_WRITE|PROT_EXEC, 473 MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); 474 475 if (realdatastart == -1) { 476 fprintf(stderr, "Unable to allocate RAM for process data\n"); 477 return realdatastart; 478 } 479 datapos = realdatastart + indx_len; 480 481 DBG_FLT("BINFMT_FLAT: Allocated data+bss+stack (%d bytes): %x\n", 482 (int)(data_len + bss_len + stack_len), (int)datapos); 483 484 fpos = ntohl(hdr->data_start); 485 #ifdef CONFIG_BINFMT_ZFLAT 486 if (flags & FLAT_FLAG_GZDATA) { 487 result = decompress_exec(bprm, fpos, (char *) datapos, 488 data_len + (relocs * sizeof(target_ulong))) 489 } else 490 #endif 491 { 492 result = target_pread(bprm->fd, datapos, 493 data_len + (relocs * sizeof(target_ulong)), 494 fpos); 495 } 496 if (result < 0) { 497 fprintf(stderr, "Unable to read data+bss\n"); 498 return result; 499 } 500 501 reloc = datapos + (ntohl(hdr->reloc_start) - text_len); 502 memp = realdatastart; 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 memp = textpos; 518 519 #ifdef CONFIG_BINFMT_ZFLAT 520 #error code needs checking 521 /* 522 * load it all in and treat it like a RAM load from now on 523 */ 524 if (flags & FLAT_FLAG_GZIP) { 525 result = decompress_exec(bprm, sizeof (struct flat_hdr), 526 (((char *) textpos) + sizeof (struct flat_hdr)), 527 (text_len + data_len + (relocs * sizeof(unsigned long)) 528 - sizeof (struct flat_hdr)), 529 0); 530 memmove((void *) datapos, (void *) realdatastart, 531 data_len + (relocs * sizeof(unsigned long))); 532 } else if (flags & FLAT_FLAG_GZDATA) { 533 fpos = 0; 534 result = bprm->file->f_op->read(bprm->file, 535 (char *) textpos, text_len, &fpos); 536 if (result < (unsigned long) -4096) 537 result = decompress_exec(bprm, text_len, (char *) datapos, 538 data_len + (relocs * sizeof(unsigned long)), 0); 539 } 540 else 541 #endif 542 { 543 result = target_pread(bprm->fd, textpos, 544 text_len, 0); 545 if (result >= 0) { 546 result = target_pread(bprm->fd, datapos, 547 data_len + (relocs * sizeof(target_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 end_code = textpos + text_len; 564 565 DBG_FLT("%s %s: TEXT=%x-%x DATA=%x-%x BSS=%x-%x\n", 566 id ? "Lib" : "Load", bprm->filename, 567 (int) start_code, (int) end_code, 568 (int) datapos, 569 (int) (datapos + data_len), 570 (int) (datapos + data_len), 571 (int) (((datapos + data_len + bss_len) + 3) & ~3)); 572 573 text_len -= sizeof(struct flat_hdr); /* the real code len */ 574 575 /* Store the current module values into the global library structure */ 576 libinfo[id].start_code = start_code; 577 libinfo[id].start_data = datapos; 578 libinfo[id].end_data = datapos + data_len; 579 libinfo[id].start_brk = datapos + data_len + bss_len; 580 libinfo[id].text_len = text_len; 581 libinfo[id].loaded = 1; 582 libinfo[id].entry = (0x00ffffff & ntohl(hdr->entry)) + textpos; 583 libinfo[id].build_date = ntohl(hdr->build_date); 584 585 /* 586 * We just load the allocations into some temporary memory to 587 * help simplify all this mumbo jumbo 588 * 589 * We've got two different sections of relocation entries. 590 * The first is the GOT which resides at the begining of the data segment 591 * and is terminated with a -1. This one can be relocated in place. 592 * The second is the extra relocation entries tacked after the image's 593 * data segment. These require a little more processing as the entry is 594 * really an offset into the image which contains an offset into the 595 * image. 596 */ 597 if (flags & FLAT_FLAG_GOTPIC) { 598 rp = datapos; 599 while (1) { 600 target_ulong addr; 601 addr = tgetl(rp); 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 tputl(rp, addr); 609 } 610 rp += sizeof(target_ulong); 611 } 612 } 613 614 /* 615 * Now run through the relocation entries. 616 * We've got to be careful here as C++ produces relocatable zero 617 * entries in the constructor and destructor tables which are then 618 * tested for being not zero (which will always occur unless we're 619 * based from address zero). This causes an endless loop as __start 620 * is at zero. The solution used is to not relocate zero addresses. 621 * This has the negative side effect of not allowing a global data 622 * reference to be statically initialised to _stext (I've moved 623 * __start to address 4 so that is okay). 624 */ 625 if (rev > OLD_FLAT_VERSION) { 626 for (i = 0; i < relocs; i++) { 627 target_ulong addr, relval; 628 629 /* Get the address of the pointer to be 630 relocated (of course, the address has to be 631 relocated first). */ 632 relval = tgetl(reloc + i * sizeof (target_ulong)); 633 addr = flat_get_relocate_addr(relval); 634 rp = calc_reloc(addr, libinfo, id, 1); 635 if (rp == RELOC_FAILED) 636 return -ENOEXEC; 637 638 /* Get the pointer's value. */ 639 addr = tgetl(rp); 640 if (addr != 0) { 641 /* 642 * Do the relocation. PIC relocs in the data section are 643 * already in target order 644 */ 645 646 #ifndef TARGET_WORDS_BIGENDIAN 647 if ((flags & FLAT_FLAG_GOTPIC) == 0) 648 addr = bswap32(addr); 649 #endif 650 addr = calc_reloc(addr, libinfo, id, 0); 651 if (addr == RELOC_FAILED) 652 return -ENOEXEC; 653 654 /* Write back the relocated pointer. */ 655 tputl(rp, addr); 656 } 657 } 658 } else { 659 for (i = 0; i < relocs; i++) { 660 target_ulong relval; 661 relval = tgetl(reloc + i * sizeof (target_ulong)); 662 old_reloc(&libinfo[0], relval); 663 } 664 } 665 666 /* zero the BSS. */ 667 memset((void*)(datapos + data_len), 0, bss_len); 668 669 return 0; 670 } 671 672 673 /****************************************************************************/ 674 #ifdef CONFIG_BINFMT_SHARED_FLAT 675 676 /* 677 * Load a shared library into memory. The library gets its own data 678 * segment (including bss) but not argv/argc/environ. 679 */ 680 681 static int load_flat_shared_library(int id, struct lib_info *libs) 682 { 683 struct linux_binprm bprm; 684 int res; 685 char buf[16]; 686 687 /* Create the file name */ 688 sprintf(buf, "/lib/lib%d.so", id); 689 690 /* Open the file up */ 691 bprm.filename = buf; 692 bprm.file = open_exec(bprm.filename); 693 res = PTR_ERR(bprm.file); 694 if (IS_ERR(bprm.file)) 695 return res; 696 697 res = prepare_binprm(&bprm); 698 699 if (res <= (unsigned long)-4096) 700 res = load_flat_file(&bprm, libs, id, NULL); 701 if (bprm.file) { 702 allow_write_access(bprm.file); 703 fput(bprm.file); 704 bprm.file = NULL; 705 } 706 return(res); 707 } 708 709 #endif /* CONFIG_BINFMT_SHARED_FLAT */ 710 711 int load_flt_binary(struct linux_binprm * bprm, struct target_pt_regs * regs, 712 struct image_info * info) 713 { 714 struct lib_info libinfo[MAX_SHARED_LIBS]; 715 target_ulong p = bprm->p; 716 target_ulong stack_len; 717 target_ulong start_addr; 718 target_ulong sp; 719 int res; 720 int i, j; 721 722 memset(libinfo, 0, sizeof(libinfo)); 723 /* 724 * We have to add the size of our arguments to our stack size 725 * otherwise it's too easy for users to create stack overflows 726 * by passing in a huge argument list. And yes, we have to be 727 * pedantic and include space for the argv/envp array as it may have 728 * a lot of entries. 729 */ 730 #define TOP_OF_ARGS (TARGET_PAGE_SIZE * MAX_ARG_PAGES - sizeof(void *)) 731 stack_len = TOP_OF_ARGS - bprm->p; /* the strings */ 732 stack_len += (bprm->argc + 1) * 4; /* the argv array */ 733 stack_len += (bprm->envc + 1) * 4; /* the envp array */ 734 735 736 res = load_flat_file(bprm, libinfo, 0, &stack_len); 737 if (res > (unsigned long)-4096) 738 return res; 739 740 /* Update data segment pointers for all libraries */ 741 for (i=0; i<MAX_SHARED_LIBS; i++) { 742 if (libinfo[i].loaded) { 743 target_ulong p; 744 p = libinfo[i].start_data; 745 for (j=0; j<MAX_SHARED_LIBS; j++) { 746 p -= 4; 747 tput32(p, libinfo[j].loaded 748 ? libinfo[j].start_data 749 : UNLOADED_LIB); 750 } 751 } 752 } 753 754 p = ((libinfo[0].start_brk + stack_len + 3) & ~3) - 4; 755 DBG_FLT("p=%x\n", (int)p); 756 757 /* Copy argv/envp. */ 758 p = copy_strings(p, bprm->envc, bprm->envp); 759 p = copy_strings(p, bprm->argc, bprm->argv); 760 /* Align stack. */ 761 sp = p & ~(target_ulong)(sizeof(target_ulong) - 1); 762 /* Enforce final stack alignment of 16 bytes. This is sufficient 763 for all current targets, and excess alignment is harmless. */ 764 stack_len = bprm->envc + bprm->argc + 2; 765 stack_len += 3; /* argc, arvg, argp */ 766 stack_len *= sizeof(target_ulong); 767 if ((sp + stack_len) & 15) 768 sp -= 16 - ((sp + stack_len) & 15); 769 sp = loader_build_argptr(bprm->envc, bprm->argc, sp, p, 1); 770 771 /* Fake some return addresses to ensure the call chain will 772 * initialise library in order for us. We are required to call 773 * lib 1 first, then 2, ... and finally the main program (id 0). 774 */ 775 start_addr = libinfo[0].entry; 776 777 #ifdef CONFIG_BINFMT_SHARED_FLAT 778 #error here 779 for (i = MAX_SHARED_LIBS-1; i>0; i--) { 780 if (libinfo[i].loaded) { 781 /* Push previos first to call address */ 782 --sp; put_user(start_addr, sp); 783 start_addr = libinfo[i].entry; 784 } 785 } 786 #endif 787 788 /* Stash our initial stack pointer into the mm structure */ 789 info->start_code = libinfo[0].start_code; 790 info->end_code = libinfo[0].start_code = libinfo[0].text_len; 791 info->start_data = libinfo[0].start_data; 792 info->end_data = libinfo[0].end_data; 793 info->start_brk = libinfo[0].start_brk; 794 info->start_stack = sp; 795 info->entry = start_addr; 796 info->code_offset = info->start_code; 797 info->data_offset = info->start_data - libinfo[0].text_len; 798 799 DBG_FLT("start_thread(entry=0x%x, start_stack=0x%x)\n", 800 (int)info->entry, (int)info->start_stack); 801 802 return 0; 803 } 804