linux-user/flatload.c

   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., 51 Franklin Street - Fifth Floor, Boston,
  18  *  MA 02110-1301, USA.
  19  *
  20  *      Copyright (C) 2006 CodeSourcery.
  21  *      Copyright (C) 2000-2003 David McCullough <davidm@snapgear.com>
  22  *      Copyright (C) 2002 Greg Ungerer <gerg@snapgear.com>
  23  *      Copyright (C) 2002 SnapGear, by Paul Dale <pauli@snapgear.com>
  24  *      Copyright (C) 2000, 2001 Lineo, by David McCullough <davidm@lineo.com>
  25  *  based heavily on:
  26  *
  27  *  linux/fs/binfmt_aout.c:
  28  *      Copyright (C) 1991, 1992, 1996  Linus Torvalds
  29  *  linux/fs/binfmt_flat.c for 2.0 kernel
  30  *          Copyright (C) 1998  Kenneth Albanowski <kjahds@kjahds.com>
  31  *      JAN/99 -- coded full program relocation (gerg@snapgear.com)
  32  */
  33
  34 /* ??? ZFLAT and shared library support is currently disabled.  */
  35
  36 /****************************************************************************/
  37
  38 #include <stdio.h>
  39 #include <stdlib.h>
  40 #include <errno.h>
  41 #include <sys/mman.h>
  42 #include <unistd.h>
  43
  44 #include "qemu.h"
  45 #include "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 flat_reloc_valid(reloc, size)             ((reloc) <= (size))
  56 #define flat_old_ram_flag(flag)                   (flag)
  57 #ifdef TARGET_WORDS_BIGENDIAN
  58 #define flat_get_relocate_addr(relval)            (relval)
  59 #else
  60 #define flat_get_relocate_addr(relval)            bswap32(relval)
  61 #endif
  62
  63 #define RELOC_FAILED 0xff00ff01         /* Relocation incorrect somewhere */
  64 #define UNLOADED_LIB 0x7ff000ff         /* Placeholder for unused library */
  65
  66 struct lib_info {
  67     abi_ulong start_code;       /* Start of text segment */
  68     abi_ulong start_data;       /* Start of data segment */
  69     abi_ulong end_data;         /* Start of bss section */
  70     abi_ulong start_brk;        /* End of data segment */
  71     abi_ulong text_len;         /* Length of text segment */
  72     abi_ulong entry;            /* Start address for this module */
  73     abi_ulong build_date;       /* When this one was compiled */
  74     short loaded;               /* Has this library been loaded? */
  75 };
  76
  77 #ifdef CONFIG_BINFMT_SHARED_FLAT
  78 static int load_flat_shared_library(int id, struct lib_info *p);
  79 #endif
  80
  81 struct linux_binprm;
  82
  83 #define ntohl(x) be32_to_cpu(x)
  84
  85 /****************************************************************************/
  86 /*
  87  * create_flat_tables() parses the env- and arg-strings in new user
  88  * memory and creates the pointer tables from them, and puts their
  89  * addresses on the "stack", returning the new stack pointer value.
  90  */
  91
  92 /* Push a block of strings onto the guest stack.  */
  93 static abi_ulong copy_strings(abi_ulong p, int n, char **s)
  94 {
  95     int len;
  96
  97     while (n-- > 0) {
  98         len = strlen(s[n]) + 1;
  99         p -= len;
 100         memcpy_to_target(p, s[n], len);
 101     }
 102
 103     return p;
 104 }
 105
 106 static int target_pread(int fd, abi_ulong ptr, abi_ulong len,
 107                         abi_ulong offset)
 108 {
 109     void *buf;
 110     int ret;
 111
 112     buf = lock_user(VERIFY_WRITE, ptr, len, 0);
 113     ret = pread(fd, buf, len, offset);
 114     unlock_user(buf, ptr, len);
 115     return ret;
 116 }
 117 /****************************************************************************/
 118
 119 #ifdef CONFIG_BINFMT_ZFLAT
 120
 121 #include <linux/zlib.h>
 122
 123 #define LBUFSIZE        4000
 124
 125 /* gzip flag byte */
 126 #define ASCII_FLAG   0x01 /* bit 0 set: file probably ASCII text */
 127 #define CONTINUATION 0x02 /* bit 1 set: continuation of multi-part gzip file */
 128 #define EXTRA_FIELD  0x04 /* bit 2 set: extra field present */
 129 #define ORIG_NAME    0x08 /* bit 3 set: original file name present */
 130 #define COMMENT      0x10 /* bit 4 set: file comment present */
 131 #define ENCRYPTED    0x20 /* bit 5 set: file is encrypted */
 132 #define RESERVED     0xC0 /* bit 6,7:   reserved */
 133
 134 static int decompress_exec(
 135         struct linux_binprm *bprm,
 136         unsigned long offset,
 137         char *dst,
 138         long len,
 139         int fd)
 140 {
 141         unsigned char *buf;
 142         z_stream strm;
 143         loff_t fpos;
 144         int ret, retval;
 145
 146         DBG_FLT("decompress_exec(offset=%x,buf=%x,len=%x)\n",(int)offset, (int)dst, (int)len);
 147
 148         memset(&strm, 0, sizeof(strm));
 149         strm.workspace = kmalloc(zlib_inflate_workspacesize(), GFP_KERNEL);
 150         if (strm.workspace == NULL) {
 151                 DBG_FLT("binfmt_flat: no memory for decompress workspace\n");
 152                 return -ENOMEM;
 153         }
 154         buf = kmalloc(LBUFSIZE, GFP_KERNEL);
 155         if (buf == NULL) {
 156                 DBG_FLT("binfmt_flat: no memory for read buffer\n");
 157                 retval = -ENOMEM;
 158                 goto out_free;
 159         }
 160
 161         /* Read in first chunk of data and parse gzip header. */
 162         fpos = offset;
 163         ret = bprm->file->f_op->read(bprm->file, buf, LBUFSIZE, &fpos);
 164
 165         strm.next_in = buf;
 166         strm.avail_in = ret;
 167         strm.total_in = 0;
 168
 169         retval = -ENOEXEC;
 170
 171         /* Check minimum size -- gzip header */
 172         if (ret < 10) {
 173                 DBG_FLT("binfmt_flat: file too small?\n");
 174                 goto out_free_buf;
 175         }
 176
 177         /* Check gzip magic number */
 178         if ((buf[0] != 037) || ((buf[1] != 0213) && (buf[1] != 0236))) {
 179                 DBG_FLT("binfmt_flat: unknown compression magic?\n");
 180                 goto out_free_buf;
 181         }
 182
 183         /* Check gzip method */
 184         if (buf[2] != 8) {
 185                 DBG_FLT("binfmt_flat: unknown compression method?\n");
 186                 goto out_free_buf;
 187         }
 188         /* Check gzip flags */
 189         if ((buf[3] & ENCRYPTED) || (buf[3] & CONTINUATION) ||
 190             (buf[3] & RESERVED)) {
 191                 DBG_FLT("binfmt_flat: unknown flags?\n");
 192                 goto out_free_buf;
 193         }
 194
 195         ret = 10;
 196         if (buf[3] & EXTRA_FIELD) {
 197                 ret += 2 + buf[10] + (buf[11] << 8);
 198                 if (unlikely(LBUFSIZE == ret)) {
 199                         DBG_FLT("binfmt_flat: buffer overflow (EXTRA)?\n");
 200                         goto out_free_buf;
 201                 }
 202         }
 203         if (buf[3] & ORIG_NAME) {
 204                 for (; ret < LBUFSIZE && (buf[ret] != 0); ret++)
 205                         ;
 206                 if (unlikely(LBUFSIZE == ret)) {
 207                         DBG_FLT("binfmt_flat: buffer overflow (ORIG_NAME)?\n");
 208                         goto out_free_buf;
 209                 }
 210         }
 211         if (buf[3] & COMMENT) {
 212                 for (;  ret < LBUFSIZE && (buf[ret] != 0); ret++)
 213                         ;
 214                 if (unlikely(LBUFSIZE == ret)) {
 215                         DBG_FLT("binfmt_flat: buffer overflow (COMMENT)?\n");
 216                         goto out_free_buf;
 217                 }
 218         }
 219
 220         strm.next_in += ret;
 221         strm.avail_in -= ret;
 222
 223         strm.next_out = dst;
 224         strm.avail_out = len;
 225         strm.total_out = 0;
 226
 227         if (zlib_inflateInit2(&strm, -MAX_WBITS) != Z_OK) {
 228                 DBG_FLT("binfmt_flat: zlib init failed?\n");
 229                 goto out_free_buf;
 230         }
 231
 232         while ((ret = zlib_inflate(&strm, Z_NO_FLUSH)) == Z_OK) {
 233                 ret = bprm->file->f_op->read(bprm->file, buf, LBUFSIZE, &fpos);
 234                 if (ret <= 0)
 235                         break;
 236                 if (ret >= (unsigned long) -4096)
 237                         break;
 238                 len -= ret;
 239
 240                 strm.next_in = buf;
 241                 strm.avail_in = ret;
 242                 strm.total_in = 0;
 243         }
 244
 245         if (ret < 0) {
 246                 DBG_FLT("binfmt_flat: decompression failed (%d), %s\n",
 247                         ret, strm.msg);
 248                 goto out_zlib;
 249         }
 250
 251         retval = 0;
 252 out_zlib:
 253         zlib_inflateEnd(&strm);
 254 out_free_buf:
 255         kfree(buf);
 256 out_free:
 257         kfree(strm.workspace);
 258 out:
 259         return retval;
 260 }
 261
 262 #endif /* CONFIG_BINFMT_ZFLAT */
 263
 264 /****************************************************************************/
 265
 266 static abi_ulong
 267 calc_reloc(abi_ulong r, struct lib_info *p, int curid, int internalp)
 268 {
 269     abi_ulong addr;
 270     int id;
 271     abi_ulong start_brk;
 272     abi_ulong start_data;
 273     abi_ulong text_len;
 274     abi_ulong start_code;
 275
 276 #ifdef CONFIG_BINFMT_SHARED_FLAT
 277 #error needs checking
 278     if (r == 0)
 279         id = curid;     /* Relocs of 0 are always self referring */
 280     else {
 281         id = (r >> 24) & 0xff;  /* Find ID for this reloc */
 282         r &= 0x00ffffff;        /* Trim ID off here */
 283     }
 284     if (id >= MAX_SHARED_LIBS) {
 285         fprintf(stderr, "BINFMT_FLAT: reference 0x%x to shared library %d\n",
 286                 (unsigned) r, id);
 287         goto failed;
 288     }
 289     if (curid != id) {
 290         if (internalp) {
 291             fprintf(stderr, "BINFMT_FLAT: reloc address 0x%x not "
 292                     "in same module (%d != %d)\n",
 293                     (unsigned) r, curid, id);
 294             goto failed;
 295         } else if ( ! p[id].loaded &&
 296                     load_flat_shared_library(id, p) > (unsigned long) -4096) {
 297             fprintf(stderr, "BINFMT_FLAT: failed to load library %d\n", id);
 298             goto failed;
 299         }
 300         /* Check versioning information (i.e. time stamps) */
 301         if (p[id].build_date && p[curid].build_date
 302             && p[curid].build_date < p[id].build_date) {
 303             fprintf(stderr, "BINFMT_FLAT: library %d is younger than %d\n",
 304                     id, curid);
 305             goto failed;
 306         }
 307     }
 308 #else
 309     id = 0;
 310 #endif
 311
 312     start_brk = p[id].start_brk;
 313     start_data = p[id].start_data;
 314     start_code = p[id].start_code;
 315     text_len = p[id].text_len;
 316
 317     if (!flat_reloc_valid(r, start_brk - start_data + text_len)) {
 318         fprintf(stderr, "BINFMT_FLAT: reloc outside program 0x%x "
 319                 "(0 - 0x%x/0x%x)\n",
 320                (int) r,(int)(start_brk-start_code),(int)text_len);
 321         goto failed;
 322     }
 323
 324     if (r < text_len)                   /* In text segment */
 325         addr = r + start_code;
 326     else                                        /* In data segment */
 327         addr = r - text_len + start_data;
 328
 329     /* Range checked already above so doing the range tests is redundant...*/
 330     return(addr);
 331
 332 failed:
 333     abort();
 334     return RELOC_FAILED;
 335 }
 336
 337 /****************************************************************************/
 338
 339 /* ??? This does not handle endianness correctly.  */
 340 static void old_reloc(struct lib_info *libinfo, uint32_t rl)
 341 {
 342 #ifdef DEBUG
 343         char *segment[] = { "TEXT", "DATA", "BSS", "*UNKNOWN*" };
 344 #endif
 345         uint32_t *ptr;
 346         uint32_t offset;
 347         int reloc_type;
 348
 349         offset = rl & 0x3fffffff;
 350         reloc_type = rl >> 30;
 351         /* ??? How to handle this?  */
 352 #if defined(CONFIG_COLDFIRE)
 353         ptr = (uint32_t *) ((unsigned long) libinfo->start_code + offset);
 354 #else
 355         ptr = (uint32_t *) ((unsigned long) libinfo->start_data + offset);
 356 #endif
 357
 358 #ifdef DEBUG
 359         fprintf(stderr, "Relocation of variable at DATASEG+%x "
 360                 "(address %p, currently %x) into segment %s\n",
 361                 offset, ptr, (int)*ptr, segment[reloc_type]);
 362 #endif
 363
 364         switch (reloc_type) {
 365         case OLD_FLAT_RELOC_TYPE_TEXT:
 366                 *ptr += libinfo->start_code;
 367                 break;
 368         case OLD_FLAT_RELOC_TYPE_DATA:
 369                 *ptr += libinfo->start_data;
 370                 break;
 371         case OLD_FLAT_RELOC_TYPE_BSS:
 372                 *ptr += libinfo->end_data;
 373                 break;
 374         default:
 375                 fprintf(stderr, "BINFMT_FLAT: Unknown relocation type=%x\n",
 376                         reloc_type);
 377                 break;
 378         }
 379         DBG_FLT("Relocation became %x\n", (int)*ptr);
 380 }
 381
 382 /****************************************************************************/
 383
 384 static int load_flat_file(struct linux_binprm * bprm,
 385                 struct lib_info *libinfo, int id, abi_ulong *extra_stack)
 386 {
 387     struct flat_hdr * hdr;
 388     abi_ulong textpos = 0, datapos = 0, result;
 389     abi_ulong realdatastart = 0;
 390     abi_ulong text_len, data_len, bss_len, stack_len, flags;
 391     abi_ulong memp = 0; /* for finding the brk area */
 392     abi_ulong extra;
 393     abi_ulong reloc = 0, rp;
 394     int i, rev, relocs = 0;
 395     abi_ulong fpos;
 396     abi_ulong start_code, end_code;
 397     abi_ulong indx_len;
 398
 399     hdr = ((struct flat_hdr *) bprm->buf);              /* exec-header */
 400
 401     text_len  = ntohl(hdr->data_start);
 402     data_len  = ntohl(hdr->data_end) - ntohl(hdr->data_start);
 403     bss_len   = ntohl(hdr->bss_end) - ntohl(hdr->data_end);
 404     stack_len = ntohl(hdr->stack_size);
 405     if (extra_stack) {
 406         stack_len += *extra_stack;
 407         *extra_stack = stack_len;
 408     }
 409     relocs    = ntohl(hdr->reloc_count);
 410     flags     = ntohl(hdr->flags);
 411     rev       = ntohl(hdr->rev);
 412
 413     DBG_FLT("BINFMT_FLAT: Loading file: %s\n", bprm->filename);
 414
 415     if (rev != FLAT_VERSION && rev != OLD_FLAT_VERSION) {
 416         fprintf(stderr, "BINFMT_FLAT: bad magic/rev (0x%x, need 0x%x)\n",
 417                 rev, (int) FLAT_VERSION);
 418         return -ENOEXEC;
 419     }
 420
 421     /* Don't allow old format executables to use shared libraries */
 422     if (rev == OLD_FLAT_VERSION && id != 0) {
 423         fprintf(stderr, "BINFMT_FLAT: shared libraries are not available\n");
 424         return -ENOEXEC;
 425     }
 426
 427     /*
 428      * fix up the flags for the older format,  there were all kinds
 429      * of endian hacks,  this only works for the simple cases
 430      */
 431     if (rev == OLD_FLAT_VERSION && flat_old_ram_flag(flags))
 432         flags = FLAT_FLAG_RAM;
 433
 434 #ifndef CONFIG_BINFMT_ZFLAT
 435     if (flags & (FLAT_FLAG_GZIP|FLAT_FLAG_GZDATA)) {
 436         fprintf(stderr, "Support for ZFLAT executables is not enabled\n");
 437         return -ENOEXEC;
 438     }
 439 #endif
 440
 441     /*
 442      * calculate the extra space we need to map in
 443      */
 444     extra = relocs * sizeof(abi_ulong);
 445     if (extra < bss_len + stack_len)
 446         extra = bss_len + stack_len;
 447
 448     /* Add space for library base pointers.  Make sure this does not
 449        misalign the  doesn't misalign the data segment.  */
 450     indx_len = MAX_SHARED_LIBS * sizeof(abi_ulong);
 451     indx_len = (indx_len + 15) & ~(abi_ulong)15;
 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->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->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         memp = realdatastart;
 504
 505     } else {
 506
 507         textpos = target_mmap(0, text_len + data_len + extra + indx_len,
 508                               PROT_READ | PROT_EXEC | PROT_WRITE,
 509                               MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
 510         if (textpos == -1 ) {
 511             fprintf(stderr, "Unable to allocate RAM for process text/data\n");
 512             return -1;
 513         }
 514
 515         realdatastart = textpos + ntohl(hdr->data_start);
 516         datapos = realdatastart + indx_len;
 517         reloc = (textpos + ntohl(hdr->reloc_start) + indx_len);
 518         memp = textpos;
 519
 520 #ifdef CONFIG_BINFMT_ZFLAT
 521 #error code needs checking
 522         /*
 523          * load it all in and treat it like a RAM load from now on
 524          */
 525         if (flags & FLAT_FLAG_GZIP) {
 526                 result = decompress_exec(bprm, sizeof (struct flat_hdr),
 527                                  (((char *) textpos) + sizeof (struct flat_hdr)),
 528                                  (text_len + data_len + (relocs * sizeof(unsigned long))
 529                                           - sizeof (struct flat_hdr)),
 530                                  0);
 531                 memmove((void *) datapos, (void *) realdatastart,
 532                                 data_len + (relocs * sizeof(unsigned long)));
 533         } else if (flags & FLAT_FLAG_GZDATA) {
 534                 fpos = 0;
 535                 result = bprm->file->f_op->read(bprm->file,
 536                                 (char *) textpos, text_len, &fpos);
 537                 if (result < (unsigned long) -4096)
 538                         result = decompress_exec(bprm, text_len, (char *) datapos,
 539                                          data_len + (relocs * sizeof(unsigned long)), 0);
 540         }
 541         else
 542 #endif
 543         {
 544             result = target_pread(bprm->fd, textpos,
 545                                   text_len, 0);
 546             if (result >= 0) {
 547                 result = target_pread(bprm->fd, datapos,
 548                     data_len + (relocs * sizeof(abi_ulong)),
 549                     ntohl(hdr->data_start));
 550             }
 551         }
 552         if (result < 0) {
 553             fprintf(stderr, "Unable to read code+data+bss\n");
 554             return result;
 555         }
 556     }
 557
 558     DBG_FLT("Mapping is 0x%x, Entry point is 0x%x, data_start is 0x%x\n",
 559             (int)textpos, 0x00ffffff&ntohl(hdr->entry),
 560             ntohl(hdr->data_start));
 561
 562     /* The main program needs a little extra setup in the task structure */
 563     start_code = textpos + sizeof (struct flat_hdr);
 564     end_code = textpos + text_len;
 565
 566     DBG_FLT("%s %s: TEXT=%x-%x DATA=%x-%x BSS=%x-%x\n",
 567             id ? "Lib" : "Load", bprm->filename,
 568             (int) start_code, (int) end_code,
 569             (int) datapos,
 570             (int) (datapos + data_len),
 571             (int) (datapos + data_len),
 572             (int) (((datapos + data_len + bss_len) + 3) & ~3));
 573
 574     text_len -= sizeof(struct flat_hdr); /* the real code len */
 575
 576     /* Store the current module values into the global library structure */
 577     libinfo[id].start_code = start_code;
 578     libinfo[id].start_data = datapos;
 579     libinfo[id].end_data = datapos + data_len;
 580     libinfo[id].start_brk = datapos + data_len + bss_len;
 581     libinfo[id].text_len = text_len;
 582     libinfo[id].loaded = 1;
 583     libinfo[id].entry = (0x00ffffff & ntohl(hdr->entry)) + textpos;
 584     libinfo[id].build_date = ntohl(hdr->build_date);
 585
 586     /*
 587      * We just load the allocations into some temporary memory to
 588      * help simplify all this mumbo jumbo
 589      *
 590      * We've got two different sections of relocation entries.
 591      * The first is the GOT which resides at the begining of the data segment
 592      * and is terminated with a -1.  This one can be relocated in place.
 593      * The second is the extra relocation entries tacked after the image's
 594      * data segment. These require a little more processing as the entry is
 595      * really an offset into the image which contains an offset into the
 596      * image.
 597      */
 598     if (flags & FLAT_FLAG_GOTPIC) {
 599         rp = datapos;
 600         while (1) {
 601             abi_ulong addr;
 602             if (get_user_ual(addr, rp))
 603                 return -EFAULT;
 604             if (addr == -1)
 605                 break;
 606             if (addr) {
 607                 addr = calc_reloc(addr, libinfo, id, 0);
 608                 if (addr == RELOC_FAILED)
 609                     return -ENOEXEC;
 610                 if (put_user_ual(addr, rp))
 611                     return -EFAULT;
 612             }
 613             rp += sizeof(abi_ulong);
 614         }
 615     }
 616
 617     /*
 618      * Now run through the relocation entries.
 619      * We've got to be careful here as C++ produces relocatable zero
 620      * entries in the constructor and destructor tables which are then
 621      * tested for being not zero (which will always occur unless we're
 622      * based from address zero).  This causes an endless loop as __start
 623      * is at zero.  The solution used is to not relocate zero addresses.
 624      * This has the negative side effect of not allowing a global data
 625      * reference to be statically initialised to _stext (I've moved
 626      * __start to address 4 so that is okay).
 627      */
 628     if (rev > OLD_FLAT_VERSION) {
 629         for (i = 0; i < relocs; i++) {
 630             abi_ulong addr, relval;
 631
 632             /* Get the address of the pointer to be
 633                relocated (of course, the address has to be
 634                relocated first).  */
 635             if (get_user_ual(relval, reloc + i * sizeof(abi_ulong)))
 636                 return -EFAULT;
 637             addr = flat_get_relocate_addr(relval);
 638             rp = calc_reloc(addr, libinfo, id, 1);
 639             if (rp == RELOC_FAILED)
 640                 return -ENOEXEC;
 641
 642             /* Get the pointer's value.  */
 643             if (get_user_ual(addr, rp))
 644                 return -EFAULT;
 645             if (addr != 0) {
 646                 /*
 647                  * Do the relocation.  PIC relocs in the data section are
 648                  * already in target order
 649                  */
 650
 651 #ifndef TARGET_WORDS_BIGENDIAN
 652                 if ((flags & FLAT_FLAG_GOTPIC) == 0)
 653                     addr = bswap32(addr);
 654 #endif
 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 (put_user_ual(addr, rp))
 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((void *)((unsigned long)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 (res <= (unsigned long)-4096)
 707                 res = load_flat_file(&bprm, libs, id, NULL);
 708         if (bprm.file) {
 709                 allow_write_access(bprm.file);
 710                 fput(bprm.file);
 711                 bprm.file = NULL;
 712         }
 713         return(res);
 714 }
 715
 716 #endif /* CONFIG_BINFMT_SHARED_FLAT */
 717
 718 int load_flt_binary(struct linux_binprm * bprm, struct target_pt_regs * regs,
 719                     struct image_info * info)
 720 {
 721     struct lib_info libinfo[MAX_SHARED_LIBS];
 722     abi_ulong p = bprm->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 #define TOP_OF_ARGS (TARGET_PAGE_SIZE * MAX_ARG_PAGES - sizeof(void *))
 738     stack_len = TOP_OF_ARGS - bprm->p;             /* the strings */
 739     stack_len += (bprm->argc + 1) * 4; /* the argv array */
 740     stack_len += (bprm->envc + 1) * 4; /* the envp array */
 741
 742
 743     res = load_flat_file(bprm, libinfo, 0, &stack_len);
 744     if (res > (unsigned long)-4096)
 745             return res;
 746
 747     /* Update data segment pointers for all libraries */
 748     for (i=0; i<MAX_SHARED_LIBS; i++) {
 749         if (libinfo[i].loaded) {
 750             abi_ulong p;
 751             p = libinfo[i].start_data;
 752             for (j=0; j<MAX_SHARED_LIBS; j++) {
 753                 p -= 4;
 754                 /* FIXME - handle put_user() failures */
 755                 if (put_user_ual(libinfo[j].loaded
 756                                  ? libinfo[j].start_data
 757                                  : UNLOADED_LIB,
 758                                  p))
 759                     return -EFAULT;
 760             }
 761         }
 762     }
 763
 764     p = ((libinfo[0].start_brk + stack_len + 3) & ~3) - 4;
 765     DBG_FLT("p=%x\n", (int)p);
 766
 767     /* Copy argv/envp.  */
 768     p = copy_strings(p, bprm->envc, bprm->envp);
 769     p = copy_strings(p, bprm->argc, bprm->argv);
 770     /* Align stack.  */
 771     sp = p & ~(abi_ulong)(sizeof(abi_ulong) - 1);
 772     /* Enforce final stack alignment of 16 bytes.  This is sufficient
 773        for all current targets, and excess alignment is harmless.  */
 774     stack_len = bprm->envc + bprm->argc + 2;
 775     stack_len += 3;     /* argc, arvg, argp */
 776     stack_len *= sizeof(abi_ulong);
 777     if ((sp + stack_len) & 15)
 778         sp -= 16 - ((sp + stack_len) & 15);
 779     sp = loader_build_argptr(bprm->envc, bprm->argc, sp, p, 1);
 780
 781     /* Fake some return addresses to ensure the call chain will
 782      * initialise library in order for us.  We are required to call
 783      * lib 1 first, then 2, ... and finally the main program (id 0).
 784      */
 785     start_addr = libinfo[0].entry;
 786
 787 #ifdef CONFIG_BINFMT_SHARED_FLAT
 788 #error here
 789     for (i = MAX_SHARED_LIBS-1; i>0; i--) {
 790             if (libinfo[i].loaded) {
 791                     /* Push previos first to call address */
 792                     --sp;
 793                     if (put_user_ual(start_addr, sp))
 794                         return -EFAULT;
 795                     start_addr = libinfo[i].entry;
 796             }
 797     }
 798 #endif
 799
 800     /* Stash our initial stack pointer into the mm structure */
 801     info->start_code = libinfo[0].start_code;
 802     info->end_code = libinfo[0].start_code = libinfo[0].text_len;
 803     info->start_data = libinfo[0].start_data;
 804     info->end_data = libinfo[0].end_data;
 805     info->start_brk = libinfo[0].start_brk;
 806     info->start_stack = sp;
 807     info->entry = start_addr;
 808     info->code_offset = info->start_code;
 809     info->data_offset = info->start_data - libinfo[0].text_len;
 810
 811     DBG_FLT("start_thread(entry=0x%x, start_stack=0x%x)\n",
 812             (int)info->entry, (int)info->start_stack);
 813
 814     return 0;
 815 }