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 <stdio.h> 37 #include <stdlib.h> 38 #include <errno.h> 39 #include <sys/mman.h> 40 #include <unistd.h> 41 42 #include "qemu.h" 43 #include "flat.h" 44 #define ntohl(x) be32_to_cpu(x) 45 #include <target_flat.h> 46 47 //#define DEBUG 48 49 #ifdef DEBUG 50 #define DBG_FLT(...) printf(__VA_ARGS__) 51 #else 52 #define DBG_FLT(...) 53 #endif 54 55 #define RELOC_FAILED 0xff00ff01 /* Relocation incorrect somewhere */ 56 #define UNLOADED_LIB 0x7ff000ff /* Placeholder for unused library */ 57 58 struct lib_info { 59 abi_ulong start_code; /* Start of text segment */ 60 abi_ulong start_data; /* Start of data segment */ 61 abi_ulong end_data; /* Start of bss section */ 62 abi_ulong start_brk; /* End of data segment */ 63 abi_ulong text_len; /* Length of text segment */ 64 abi_ulong entry; /* Start address for this module */ 65 abi_ulong build_date; /* When this one was compiled */ 66 short loaded; /* Has this library been loaded? */ 67 }; 68 69 #ifdef CONFIG_BINFMT_SHARED_FLAT 70 static int load_flat_shared_library(int id, struct lib_info *p); 71 #endif 72 73 struct linux_binprm; 74 75 /****************************************************************************/ 76 /* 77 * create_flat_tables() parses the env- and arg-strings in new user 78 * memory and creates the pointer tables from them, and puts their 79 * addresses on the "stack", returning the new stack pointer value. 80 */ 81 82 /* Push a block of strings onto the guest stack. */ 83 static abi_ulong copy_strings(abi_ulong p, int n, char **s) 84 { 85 int len; 86 87 while (n-- > 0) { 88 len = strlen(s[n]) + 1; 89 p -= len; 90 memcpy_to_target(p, s[n], len); 91 } 92 93 return p; 94 } 95 96 static int target_pread(int fd, abi_ulong ptr, abi_ulong len, 97 abi_ulong offset) 98 { 99 void *buf; 100 int ret; 101 102 buf = lock_user(VERIFY_WRITE, ptr, len, 0); 103 ret = pread(fd, buf, len, offset); 104 unlock_user(buf, ptr, len); 105 return ret; 106 } 107 /****************************************************************************/ 108 109 #ifdef CONFIG_BINFMT_ZFLAT 110 111 #include <linux/zlib.h> 112 113 #define LBUFSIZE 4000 114 115 /* gzip flag byte */ 116 #define ASCII_FLAG 0x01 /* bit 0 set: file probably ASCII text */ 117 #define CONTINUATION 0x02 /* bit 1 set: continuation of multi-part gzip file */ 118 #define EXTRA_FIELD 0x04 /* bit 2 set: extra field present */ 119 #define ORIG_NAME 0x08 /* bit 3 set: original file name present */ 120 #define COMMENT 0x10 /* bit 4 set: file comment present */ 121 #define ENCRYPTED 0x20 /* bit 5 set: file is encrypted */ 122 #define RESERVED 0xC0 /* bit 6,7: reserved */ 123 124 static int decompress_exec( 125 struct linux_binprm *bprm, 126 unsigned long offset, 127 char *dst, 128 long len, 129 int fd) 130 { 131 unsigned char *buf; 132 z_stream strm; 133 loff_t fpos; 134 int ret, retval; 135 136 DBG_FLT("decompress_exec(offset=%x,buf=%x,len=%x)\n",(int)offset, (int)dst, (int)len); 137 138 memset(&strm, 0, sizeof(strm)); 139 strm.workspace = kmalloc(zlib_inflate_workspacesize(), GFP_KERNEL); 140 if (strm.workspace == NULL) { 141 DBG_FLT("binfmt_flat: no memory for decompress workspace\n"); 142 return -ENOMEM; 143 } 144 buf = kmalloc(LBUFSIZE, GFP_KERNEL); 145 if (buf == NULL) { 146 DBG_FLT("binfmt_flat: no memory for read buffer\n"); 147 retval = -ENOMEM; 148 goto out_free; 149 } 150 151 /* Read in first chunk of data and parse gzip header. */ 152 fpos = offset; 153 ret = bprm->file->f_op->read(bprm->file, buf, LBUFSIZE, &fpos); 154 155 strm.next_in = buf; 156 strm.avail_in = ret; 157 strm.total_in = 0; 158 159 retval = -ENOEXEC; 160 161 /* Check minimum size -- gzip header */ 162 if (ret < 10) { 163 DBG_FLT("binfmt_flat: file too small?\n"); 164 goto out_free_buf; 165 } 166 167 /* Check gzip magic number */ 168 if ((buf[0] != 037) || ((buf[1] != 0213) && (buf[1] != 0236))) { 169 DBG_FLT("binfmt_flat: unknown compression magic?\n"); 170 goto out_free_buf; 171 } 172 173 /* Check gzip method */ 174 if (buf[2] != 8) { 175 DBG_FLT("binfmt_flat: unknown compression method?\n"); 176 goto out_free_buf; 177 } 178 /* Check gzip flags */ 179 if ((buf[3] & ENCRYPTED) || (buf[3] & CONTINUATION) || 180 (buf[3] & RESERVED)) { 181 DBG_FLT("binfmt_flat: unknown flags?\n"); 182 goto out_free_buf; 183 } 184 185 ret = 10; 186 if (buf[3] & EXTRA_FIELD) { 187 ret += 2 + buf[10] + (buf[11] << 8); 188 if (unlikely(LBUFSIZE == ret)) { 189 DBG_FLT("binfmt_flat: buffer overflow (EXTRA)?\n"); 190 goto out_free_buf; 191 } 192 } 193 if (buf[3] & ORIG_NAME) { 194 for (; ret < LBUFSIZE && (buf[ret] != 0); ret++) 195 ; 196 if (unlikely(LBUFSIZE == ret)) { 197 DBG_FLT("binfmt_flat: buffer overflow (ORIG_NAME)?\n"); 198 goto out_free_buf; 199 } 200 } 201 if (buf[3] & COMMENT) { 202 for (; ret < LBUFSIZE && (buf[ret] != 0); ret++) 203 ; 204 if (unlikely(LBUFSIZE == ret)) { 205 DBG_FLT("binfmt_flat: buffer overflow (COMMENT)?\n"); 206 goto out_free_buf; 207 } 208 } 209 210 strm.next_in += ret; 211 strm.avail_in -= ret; 212 213 strm.next_out = dst; 214 strm.avail_out = len; 215 strm.total_out = 0; 216 217 if (zlib_inflateInit2(&strm, -MAX_WBITS) != Z_OK) { 218 DBG_FLT("binfmt_flat: zlib init failed?\n"); 219 goto out_free_buf; 220 } 221 222 while ((ret = zlib_inflate(&strm, Z_NO_FLUSH)) == Z_OK) { 223 ret = bprm->file->f_op->read(bprm->file, buf, LBUFSIZE, &fpos); 224 if (ret <= 0) 225 break; 226 if (ret >= (unsigned long) -4096) 227 break; 228 len -= ret; 229 230 strm.next_in = buf; 231 strm.avail_in = ret; 232 strm.total_in = 0; 233 } 234 235 if (ret < 0) { 236 DBG_FLT("binfmt_flat: decompression failed (%d), %s\n", 237 ret, strm.msg); 238 goto out_zlib; 239 } 240 241 retval = 0; 242 out_zlib: 243 zlib_inflateEnd(&strm); 244 out_free_buf: 245 kfree(buf); 246 out_free: 247 kfree(strm.workspace); 248 out: 249 return retval; 250 } 251 252 #endif /* CONFIG_BINFMT_ZFLAT */ 253 254 /****************************************************************************/ 255 256 static abi_ulong 257 calc_reloc(abi_ulong r, struct lib_info *p, int curid, int internalp) 258 { 259 abi_ulong addr; 260 int id; 261 abi_ulong start_brk; 262 abi_ulong start_data; 263 abi_ulong text_len; 264 abi_ulong start_code; 265 266 #ifdef CONFIG_BINFMT_SHARED_FLAT 267 #error needs checking 268 if (r == 0) 269 id = curid; /* Relocs of 0 are always self referring */ 270 else { 271 id = (r >> 24) & 0xff; /* Find ID for this reloc */ 272 r &= 0x00ffffff; /* Trim ID off here */ 273 } 274 if (id >= MAX_SHARED_LIBS) { 275 fprintf(stderr, "BINFMT_FLAT: reference 0x%x to shared library %d\n", 276 (unsigned) r, id); 277 goto failed; 278 } 279 if (curid != id) { 280 if (internalp) { 281 fprintf(stderr, "BINFMT_FLAT: reloc address 0x%x not " 282 "in same module (%d != %d)\n", 283 (unsigned) r, curid, id); 284 goto failed; 285 } else if ( ! p[id].loaded && 286 load_flat_shared_library(id, p) > (unsigned long) -4096) { 287 fprintf(stderr, "BINFMT_FLAT: failed to load library %d\n", id); 288 goto failed; 289 } 290 /* Check versioning information (i.e. time stamps) */ 291 if (p[id].build_date && p[curid].build_date 292 && p[curid].build_date < p[id].build_date) { 293 fprintf(stderr, "BINFMT_FLAT: library %d is younger than %d\n", 294 id, curid); 295 goto failed; 296 } 297 } 298 #else 299 id = 0; 300 #endif 301 302 start_brk = p[id].start_brk; 303 start_data = p[id].start_data; 304 start_code = p[id].start_code; 305 text_len = p[id].text_len; 306 307 if (!flat_reloc_valid(r, start_brk - start_data + text_len)) { 308 fprintf(stderr, "BINFMT_FLAT: reloc outside program 0x%x " 309 "(0 - 0x%x/0x%x)\n", 310 (int) r,(int)(start_brk-start_code),(int)text_len); 311 goto failed; 312 } 313 314 if (r < text_len) /* In text segment */ 315 addr = r + start_code; 316 else /* In data segment */ 317 addr = r - text_len + start_data; 318 319 /* Range checked already above so doing the range tests is redundant...*/ 320 return(addr); 321 322 failed: 323 abort(); 324 return RELOC_FAILED; 325 } 326 327 /****************************************************************************/ 328 329 /* ??? This does not handle endianness correctly. */ 330 static void old_reloc(struct lib_info *libinfo, uint32_t rl) 331 { 332 #ifdef DEBUG 333 const char *segment[] = { "TEXT", "DATA", "BSS", "*UNKNOWN*" }; 334 #endif 335 uint32_t *ptr; 336 uint32_t offset; 337 int reloc_type; 338 339 offset = rl & 0x3fffffff; 340 reloc_type = rl >> 30; 341 /* ??? How to handle this? */ 342 #if defined(CONFIG_COLDFIRE) 343 ptr = (uint32_t *) ((unsigned long) libinfo->start_code + offset); 344 #else 345 ptr = (uint32_t *) ((unsigned long) libinfo->start_data + offset); 346 #endif 347 348 #ifdef DEBUG 349 fprintf(stderr, "Relocation of variable at DATASEG+%x " 350 "(address %p, currently %x) into segment %s\n", 351 offset, ptr, (int)*ptr, segment[reloc_type]); 352 #endif 353 354 switch (reloc_type) { 355 case OLD_FLAT_RELOC_TYPE_TEXT: 356 *ptr += libinfo->start_code; 357 break; 358 case OLD_FLAT_RELOC_TYPE_DATA: 359 *ptr += libinfo->start_data; 360 break; 361 case OLD_FLAT_RELOC_TYPE_BSS: 362 *ptr += libinfo->end_data; 363 break; 364 default: 365 fprintf(stderr, "BINFMT_FLAT: Unknown relocation type=%x\n", 366 reloc_type); 367 break; 368 } 369 DBG_FLT("Relocation became %x\n", (int)*ptr); 370 } 371 372 /****************************************************************************/ 373 374 static int load_flat_file(struct linux_binprm * bprm, 375 struct lib_info *libinfo, int id, abi_ulong *extra_stack) 376 { 377 struct flat_hdr * hdr; 378 abi_ulong textpos = 0, datapos = 0; 379 abi_long result; 380 abi_ulong realdatastart = 0; 381 abi_ulong text_len, data_len, bss_len, stack_len, flags; 382 abi_ulong extra; 383 abi_ulong reloc = 0, rp; 384 int i, rev, relocs = 0; 385 abi_ulong fpos; 386 abi_ulong start_code; 387 abi_ulong indx_len; 388 389 hdr = ((struct flat_hdr *) bprm->buf); /* exec-header */ 390 391 text_len = ntohl(hdr->data_start); 392 data_len = ntohl(hdr->data_end) - ntohl(hdr->data_start); 393 bss_len = ntohl(hdr->bss_end) - ntohl(hdr->data_end); 394 stack_len = ntohl(hdr->stack_size); 395 if (extra_stack) { 396 stack_len += *extra_stack; 397 *extra_stack = stack_len; 398 } 399 relocs = ntohl(hdr->reloc_count); 400 flags = ntohl(hdr->flags); 401 rev = ntohl(hdr->rev); 402 403 DBG_FLT("BINFMT_FLAT: Loading file: %s\n", bprm->filename); 404 405 if (rev != FLAT_VERSION && rev != OLD_FLAT_VERSION) { 406 fprintf(stderr, "BINFMT_FLAT: bad magic/rev (0x%x, need 0x%x)\n", 407 rev, (int) FLAT_VERSION); 408 return -ENOEXEC; 409 } 410 411 /* Don't allow old format executables to use shared libraries */ 412 if (rev == OLD_FLAT_VERSION && id != 0) { 413 fprintf(stderr, "BINFMT_FLAT: shared libraries are not available\n"); 414 return -ENOEXEC; 415 } 416 417 /* 418 * fix up the flags for the older format, there were all kinds 419 * of endian hacks, this only works for the simple cases 420 */ 421 if (rev == OLD_FLAT_VERSION && flat_old_ram_flag(flags)) 422 flags = FLAT_FLAG_RAM; 423 424 #ifndef CONFIG_BINFMT_ZFLAT 425 if (flags & (FLAT_FLAG_GZIP|FLAT_FLAG_GZDATA)) { 426 fprintf(stderr, "Support for ZFLAT executables is not enabled\n"); 427 return -ENOEXEC; 428 } 429 #endif 430 431 /* 432 * calculate the extra space we need to map in 433 */ 434 extra = relocs * sizeof(abi_ulong); 435 if (extra < bss_len + stack_len) 436 extra = bss_len + stack_len; 437 438 /* Add space for library base pointers. Make sure this does not 439 misalign the doesn't misalign the data segment. */ 440 indx_len = MAX_SHARED_LIBS * sizeof(abi_ulong); 441 indx_len = (indx_len + 15) & ~(abi_ulong)15; 442 443 /* 444 * there are a couple of cases here, the separate code/data 445 * case, and then the fully copied to RAM case which lumps 446 * it all together. 447 */ 448 if ((flags & (FLAT_FLAG_RAM|FLAT_FLAG_GZIP)) == 0) { 449 /* 450 * this should give us a ROM ptr, but if it doesn't we don't 451 * really care 452 */ 453 DBG_FLT("BINFMT_FLAT: ROM mapping of file (we hope)\n"); 454 455 textpos = target_mmap(0, text_len, PROT_READ|PROT_EXEC, 456 MAP_PRIVATE, bprm->fd, 0); 457 if (textpos == -1) { 458 fprintf(stderr, "Unable to mmap process text\n"); 459 return -1; 460 } 461 462 realdatastart = target_mmap(0, data_len + extra + indx_len, 463 PROT_READ|PROT_WRITE|PROT_EXEC, 464 MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); 465 466 if (realdatastart == -1) { 467 fprintf(stderr, "Unable to allocate RAM for process data\n"); 468 return realdatastart; 469 } 470 datapos = realdatastart + indx_len; 471 472 DBG_FLT("BINFMT_FLAT: Allocated data+bss+stack (%d bytes): %x\n", 473 (int)(data_len + bss_len + stack_len), (int)datapos); 474 475 fpos = ntohl(hdr->data_start); 476 #ifdef CONFIG_BINFMT_ZFLAT 477 if (flags & FLAT_FLAG_GZDATA) { 478 result = decompress_exec(bprm, fpos, (char *) datapos, 479 data_len + (relocs * sizeof(abi_ulong))) 480 } else 481 #endif 482 { 483 result = target_pread(bprm->fd, datapos, 484 data_len + (relocs * sizeof(abi_ulong)), 485 fpos); 486 } 487 if (result < 0) { 488 fprintf(stderr, "Unable to read data+bss\n"); 489 return result; 490 } 491 492 reloc = datapos + (ntohl(hdr->reloc_start) - text_len); 493 494 } else { 495 496 textpos = target_mmap(0, text_len + data_len + extra + indx_len, 497 PROT_READ | PROT_EXEC | PROT_WRITE, 498 MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); 499 if (textpos == -1 ) { 500 fprintf(stderr, "Unable to allocate RAM for process text/data\n"); 501 return -1; 502 } 503 504 realdatastart = textpos + ntohl(hdr->data_start); 505 datapos = realdatastart + indx_len; 506 reloc = (textpos + ntohl(hdr->reloc_start) + indx_len); 507 508 #ifdef CONFIG_BINFMT_ZFLAT 509 #error code needs checking 510 /* 511 * load it all in and treat it like a RAM load from now on 512 */ 513 if (flags & FLAT_FLAG_GZIP) { 514 result = decompress_exec(bprm, sizeof (struct flat_hdr), 515 (((char *) textpos) + sizeof (struct flat_hdr)), 516 (text_len + data_len + (relocs * sizeof(unsigned long)) 517 - sizeof (struct flat_hdr)), 518 0); 519 memmove((void *) datapos, (void *) realdatastart, 520 data_len + (relocs * sizeof(unsigned long))); 521 } else if (flags & FLAT_FLAG_GZDATA) { 522 fpos = 0; 523 result = bprm->file->f_op->read(bprm->file, 524 (char *) textpos, text_len, &fpos); 525 if (result < (unsigned long) -4096) 526 result = decompress_exec(bprm, text_len, (char *) datapos, 527 data_len + (relocs * sizeof(unsigned long)), 0); 528 } 529 else 530 #endif 531 { 532 result = target_pread(bprm->fd, textpos, 533 text_len, 0); 534 if (result >= 0) { 535 result = target_pread(bprm->fd, datapos, 536 data_len + (relocs * sizeof(abi_ulong)), 537 ntohl(hdr->data_start)); 538 } 539 } 540 if (result < 0) { 541 fprintf(stderr, "Unable to read code+data+bss\n"); 542 return result; 543 } 544 } 545 546 DBG_FLT("Mapping is 0x%x, Entry point is 0x%x, data_start is 0x%x\n", 547 (int)textpos, 0x00ffffff&ntohl(hdr->entry), 548 ntohl(hdr->data_start)); 549 550 /* The main program needs a little extra setup in the task structure */ 551 start_code = textpos + sizeof (struct flat_hdr); 552 553 DBG_FLT("%s %s: TEXT=%x-%x DATA=%x-%x BSS=%x-%x\n", 554 id ? "Lib" : "Load", bprm->filename, 555 (int) start_code, (int) (textpos + text_len), 556 (int) datapos, 557 (int) (datapos + data_len), 558 (int) (datapos + data_len), 559 (int) (((datapos + data_len + bss_len) + 3) & ~3)); 560 561 text_len -= sizeof(struct flat_hdr); /* the real code len */ 562 563 /* Store the current module values into the global library structure */ 564 libinfo[id].start_code = start_code; 565 libinfo[id].start_data = datapos; 566 libinfo[id].end_data = datapos + data_len; 567 libinfo[id].start_brk = datapos + data_len + bss_len; 568 libinfo[id].text_len = text_len; 569 libinfo[id].loaded = 1; 570 libinfo[id].entry = (0x00ffffff & ntohl(hdr->entry)) + textpos; 571 libinfo[id].build_date = ntohl(hdr->build_date); 572 573 /* 574 * We just load the allocations into some temporary memory to 575 * help simplify all this mumbo jumbo 576 * 577 * We've got two different sections of relocation entries. 578 * The first is the GOT which resides at the beginning of the data segment 579 * and is terminated with a -1. This one can be relocated in place. 580 * The second is the extra relocation entries tacked after the image's 581 * data segment. These require a little more processing as the entry is 582 * really an offset into the image which contains an offset into the 583 * image. 584 */ 585 if (flags & FLAT_FLAG_GOTPIC) { 586 rp = datapos; 587 while (1) { 588 abi_ulong addr; 589 if (get_user_ual(addr, rp)) 590 return -EFAULT; 591 if (addr == -1) 592 break; 593 if (addr) { 594 addr = calc_reloc(addr, libinfo, id, 0); 595 if (addr == RELOC_FAILED) 596 return -ENOEXEC; 597 if (put_user_ual(addr, rp)) 598 return -EFAULT; 599 } 600 rp += sizeof(abi_ulong); 601 } 602 } 603 604 /* 605 * Now run through the relocation entries. 606 * We've got to be careful here as C++ produces relocatable zero 607 * entries in the constructor and destructor tables which are then 608 * tested for being not zero (which will always occur unless we're 609 * based from address zero). This causes an endless loop as __start 610 * is at zero. The solution used is to not relocate zero addresses. 611 * This has the negative side effect of not allowing a global data 612 * reference to be statically initialised to _stext (I've moved 613 * __start to address 4 so that is okay). 614 */ 615 if (rev > OLD_FLAT_VERSION) { 616 abi_ulong persistent = 0; 617 for (i = 0; i < relocs; i++) { 618 abi_ulong addr, relval; 619 620 /* Get the address of the pointer to be 621 relocated (of course, the address has to be 622 relocated first). */ 623 if (get_user_ual(relval, reloc + i * sizeof(abi_ulong))) 624 return -EFAULT; 625 relval = ntohl(relval); 626 if (flat_set_persistent(relval, &persistent)) 627 continue; 628 addr = flat_get_relocate_addr(relval); 629 rp = calc_reloc(addr, libinfo, id, 1); 630 if (rp == RELOC_FAILED) 631 return -ENOEXEC; 632 633 /* Get the pointer's value. */ 634 if (get_user_ual(addr, rp)) 635 return -EFAULT; 636 addr = flat_get_addr_from_rp(rp, relval, flags, &persistent); 637 if (addr != 0) { 638 /* 639 * Do the relocation. PIC relocs in the data section are 640 * already in target order 641 */ 642 if ((flags & FLAT_FLAG_GOTPIC) == 0) 643 addr = ntohl(addr); 644 addr = calc_reloc(addr, libinfo, id, 0); 645 if (addr == RELOC_FAILED) 646 return -ENOEXEC; 647 648 /* Write back the relocated pointer. */ 649 if (flat_put_addr_at_rp(rp, addr, relval)) 650 return -EFAULT; 651 } 652 } 653 } else { 654 for (i = 0; i < relocs; i++) { 655 abi_ulong relval; 656 if (get_user_ual(relval, reloc + i * sizeof(abi_ulong))) 657 return -EFAULT; 658 old_reloc(&libinfo[0], relval); 659 } 660 } 661 662 /* zero the BSS. */ 663 memset(g2h(datapos + data_len), 0, bss_len); 664 665 return 0; 666 } 667 668 669 /****************************************************************************/ 670 #ifdef CONFIG_BINFMT_SHARED_FLAT 671 672 /* 673 * Load a shared library into memory. The library gets its own data 674 * segment (including bss) but not argv/argc/environ. 675 */ 676 677 static int load_flat_shared_library(int id, struct lib_info *libs) 678 { 679 struct linux_binprm bprm; 680 int res; 681 char buf[16]; 682 683 /* Create the file name */ 684 sprintf(buf, "/lib/lib%d.so", id); 685 686 /* Open the file up */ 687 bprm.filename = buf; 688 bprm.file = open_exec(bprm.filename); 689 res = PTR_ERR(bprm.file); 690 if (IS_ERR(bprm.file)) 691 return res; 692 693 res = prepare_binprm(&bprm); 694 695 if (res <= (unsigned long)-4096) 696 res = load_flat_file(&bprm, libs, id, NULL); 697 if (bprm.file) { 698 allow_write_access(bprm.file); 699 fput(bprm.file); 700 bprm.file = NULL; 701 } 702 return(res); 703 } 704 705 #endif /* CONFIG_BINFMT_SHARED_FLAT */ 706 707 int load_flt_binary(struct linux_binprm * bprm, struct target_pt_regs * regs, 708 struct image_info * info) 709 { 710 struct lib_info libinfo[MAX_SHARED_LIBS]; 711 abi_ulong p = bprm->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