fs/binfmt_flat.c

   1 /*
   2  *  linux/fs/binfmt_flat.c
   3  *
   4  *      Copyright (C) 2000, 2001 Lineo, by David McCullough <davidm@uclinux.org>
   5  *      Copyright (C) 2002 Greg Ungerer <gerg@snapgear.com>
   6  *
   7  *  based heavily on:
   8  *
   9  *  linux/fs/binfmt_aout.c:
  10  *      Copyright (C) 1991, 1992, 1996  Linus Torvalds
  11  *  linux/fs/binfmt_flat.c for 2.0 kernel
  12  *      Copyright (C) 1998  Kenneth Albanowski <kjahds@kjahds.com>
  13  *      JAN/99 -- coded full program relocation (gerg@snapgear.com)
  14  */
  15
  16 #include <linux/module.h>
  17 #include <linux/config.h>
  18 #include <linux/kernel.h>
  19 #include <linux/sched.h>
  20 #include <linux/mm.h>
  21 #include <linux/mman.h>
  22 #include <linux/a.out.h>
  23 #include <linux/errno.h>
  24 #include <linux/signal.h>
  25 #include <linux/string.h>
  26 #include <linux/fs.h>
  27 #include <linux/file.h>
  28 #include <linux/stat.h>
  29 #include <linux/fcntl.h>
  30 #include <linux/ptrace.h>
  31 #include <linux/user.h>
  32 #include <linux/slab.h>
  33 #include <linux/binfmts.h>
  34 #include <linux/personality.h>
  35 #include <linux/init.h>
  36 #include <linux/flat.h>
  37
  38 #include <asm/byteorder.h>
  39 #include <asm/system.h>
  40 #include <asm/uaccess.h>
  41 #include <asm/pgalloc.h>
  42 #include <asm/unaligned.h>
  43 #include <asm/cacheflush.h>
  44
  45 #undef DEBUG
  46 #ifdef DEBUG
  47 #define DBG_FLT(a...)   printk(##a)
  48 #else
  49 #define DBG_FLT(a...)
  50 #endif
  51
  52 static int load_flat_binary(struct linux_binprm *, struct pt_regs * regs);
  53 static int load_flat_library(struct file*);
  54 extern void dump_thread(struct pt_regs *, struct user *);
  55
  56 static struct linux_binfmt flat_format = {
  57         NULL, THIS_MODULE, load_flat_binary, load_flat_library, NULL, PAGE_SIZE
  58 };
  59
  60
  61 /*
  62  * create_flat_tables() parses the env- and arg-strings in new user
  63  * memory and creates the pointer tables from them, and puts their
  64  * addresses on the "stack", returning the new stack pointer value.
  65  */
  66 static unsigned long create_flat_tables(
  67         unsigned long pp,
  68         struct linux_binprm * bprm)
  69 {
  70         unsigned long *argv,*envp;
  71         unsigned long * sp;
  72         char * p = (char*)pp;
  73         int argc = bprm->argc;
  74         int envc = bprm->envc;
  75         char dummy;
  76
  77         sp = (unsigned long *) ((-(unsigned long)sizeof(char *))&(unsigned long) p);
  78
  79         sp -= envc+1;
  80         envp = sp;
  81         sp -= argc+1;
  82         argv = sp;
  83         if (flat_argvp_envp_on_stack()) {
  84                 put_user((unsigned long) envp, --sp);
  85                 put_user((unsigned long) argv, --sp);
  86         }
  87         put_user(argc,--sp);
  88         current->mm->arg_start = (unsigned long) p;
  89         while (argc-->0) {
  90                 put_user((unsigned long) p, argv++);
  91                 do {
  92                         get_user(dummy, p); p++;
  93                 } while (dummy);
  94         }
  95         put_user((unsigned long) NULL, argv);
  96         current->mm->arg_end = current->mm->env_start = (unsigned long) p;
  97         while (envc-->0) {
  98                 put_user((unsigned long)p, envp); envp++;
  99                 do {
 100                         get_user(dummy, p); p++;
 101                 } while (dummy);
 102         }
 103         put_user((unsigned long) NULL, envp);
 104         current->mm->env_end = (unsigned long) p;
 105         return (unsigned long)sp;
 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;
 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                 return -ENOMEM;
 148         }
 149
 150         /* Read in first chunk of data and parse gzip header. */
 151         fpos = offset;
 152         ret = bprm->file->f_op->read(bprm->file, buf, LBUFSIZE, &fpos);
 153
 154         strm.next_in = buf;
 155         strm.avail_in = ret;
 156         strm.total_in = 0;
 157
 158         /* Check minimum size -- gzip header */
 159         if (ret < 10) {
 160                 DBG_FLT("binfmt_flat: file too small?\n");
 161                 return -ENOEXEC;
 162         }
 163
 164         /* Check gzip magic number */
 165         if ((buf[0] != 037) || ((buf[1] != 0213) && (buf[1] != 0236))) {
 166                 DBG_FLT("binfmt_flat: unknown compression magic?\n");
 167                 return -ENOEXEC;
 168         }
 169
 170         /* Check gzip method */
 171         if (buf[2] != 8) {
 172                 DBG_FLT("binfmt_flat: unknown compression method?\n");
 173                 return -ENOEXEC;
 174         }
 175         /* Check gzip flags */
 176         if ((buf[3] & ENCRYPTED) || (buf[3] & CONTINUATION) ||
 177             (buf[3] & RESERVED)) {
 178                 DBG_FLT("binfmt_flat: unknown flags?\n");
 179                 return -ENOEXEC;
 180         }
 181
 182         ret = 10;
 183         if (buf[3] & EXTRA_FIELD) {
 184                 ret += 2 + buf[10] + (buf[11] << 8);
 185                 if (unlikely(LBUFSIZE == ret)) {
 186                         DBG_FLAT("binfmt_flat: buffer overflow (EXTRA)?\n");
 187                         return -ENOEXEC;
 188                 }
 189         }
 190         if (buf[3] & ORIG_NAME) {
 191                 for (; ret < LBUFSIZE && (buf[ret] != 0); ret++)
 192                         ;
 193                 if (unlikely(LBUFSIZE == ret)) {
 194                         DBG_FLAT("binfmt_flat: buffer overflow (ORIG_NAME)?\n");
 195                         return -ENOEXEC;
 196                 }
 197         }
 198         if (buf[3] & COMMENT) {
 199                 for (;  ret < LBUFSIZE && (buf[ret] != 0); ret++)
 200                         ;
 201                 if (unlikely(LBUFSIZE == ret)) {
 202                         DBG_FLAT("binfmt_flat: buffer overflow (COMMENT)?\n");
 203                         return -ENOEXEC;
 204                 }
 205         }
 206
 207         strm.next_in += ret;
 208         strm.avail_in -= ret;
 209
 210         strm.next_out = dst;
 211         strm.avail_out = len;
 212         strm.total_out = 0;
 213
 214         if (zlib_inflateInit2(&strm, -MAX_WBITS) != Z_OK) {
 215                 DBG_FLT("binfmt_flat: zlib init failed?\n");
 216                 return -ENOEXEC;
 217         }
 218
 219         while ((ret = zlib_inflate(&strm, Z_NO_FLUSH)) == Z_OK) {
 220                 ret = bprm->file->f_op->read(bprm->file, buf, LBUFSIZE, &fpos);
 221                 if (ret <= 0)
 222                         break;
 223                 if (ret >= (unsigned long) -4096)
 224                         break;
 225                 len -= ret;
 226
 227                 strm.next_in = buf;
 228                 strm.avail_in = ret;
 229                 strm.total_in = 0;
 230         }
 231
 232         if (ret < 0) {
 233                 DBG_FLT("binfmt_flat: decompression failed (%d), %s\n",
 234                         ret, strm.msg);
 235                 return -ENOEXEC;
 236         }
 237
 238         zlib_inflateEnd(&strm);
 239         kfree(buf);
 240         kfree(strm.workspace);
 241         return 0;
 242 }
 243
 244 #endif /* CONFIG_BINFMT_ZFLAT */
 245
 246
 247 static unsigned long
 248 calc_reloc(unsigned long r, unsigned long text_len)
 249 {
 250         unsigned long addr;
 251
 252         if (r > current->mm->start_brk - current->mm->start_data + text_len) {
 253                 printk("BINFMT_FLAT: reloc outside program 0x%x (0 - 0x%x), killing!\n",
 254                                 (int) r,(int)(current->mm->start_brk-current->mm->start_code));
 255                 send_sig(SIGSEGV, current, 0);
 256                 return(current->mm->start_brk); /* return something safe to write to */
 257         }
 258
 259         if (r < text_len) {
 260                 /* In text segment */
 261                 return r + current->mm->start_code;
 262         }
 263
 264         /*
 265          * we allow inclusive ranges here so that programs may do things
 266          * like reference the end of data (_end) without failing these tests
 267          */
 268         addr =  r - text_len + current->mm->start_data;
 269         if (addr >= current->mm->start_code &&
 270                         addr <= current->mm->start_code + text_len)
 271                 return(addr);
 272
 273         if (addr >= current->mm->start_data &&
 274                         addr <= current->mm->start_brk)
 275                 return(addr);
 276
 277         printk("BINFMT_FLAT: reloc addr outside text/data 0x%x "
 278                         "code(0x%x - 0x%x) data(0x%x - 0x%x) killing\n", (int) addr,
 279                         (int) current->mm->start_code,
 280                         (int) (current->mm->start_code + text_len),
 281                         (int) current->mm->start_data,
 282                         (int) current->mm->start_brk);
 283         send_sig(SIGSEGV, current, 0);
 284
 285         return(current->mm->start_brk); /* return something safe to write to */
 286 }
 287
 288
 289 void old_reloc(unsigned long rl)
 290 {
 291 #ifdef DEBUG
 292         char *segment[] = { "TEXT", "DATA", "BSS", "*UNKNOWN*" };
 293 #endif
 294         flat_v2_reloc_t r;
 295         unsigned long *ptr;
 296
 297         r.value = rl;
 298 #if defined(CONFIG_COLDFIRE)
 299         ptr = (unsigned long *) (current->mm->start_code + r.reloc.offset);
 300 #else
 301         ptr = (unsigned long *) (current->mm->start_data + r.reloc.offset);
 302 #endif
 303
 304 #ifdef DEBUG
 305         printk("Relocation of variable at DATASEG+%x "
 306                 "(address %p, currently %x) into segment %s\n",
 307                 r.reloc.offset, ptr, (int)*ptr, segment[r.reloc.type]);
 308 #endif
 309
 310         switch (r.reloc.type) {
 311         case OLD_FLAT_RELOC_TYPE_TEXT:
 312                 *ptr += current->mm->start_code;
 313                 break;
 314         case OLD_FLAT_RELOC_TYPE_DATA:
 315                 *ptr += current->mm->start_data;
 316                 break;
 317         case OLD_FLAT_RELOC_TYPE_BSS:
 318                 *ptr += current->mm->end_data;
 319                 break;
 320         default:
 321                 printk("BINFMT_FLAT: Unknown relocation type=%x\n", r.reloc.type);
 322                 break;
 323         }
 324
 325 #ifdef DEBUG
 326         printk("Relocation became %x\n", (int)*ptr);
 327 #endif
 328 }
 329
 330
 331 /*
 332  * These are the functions used to load flat style executables and shared
 333  * libraries.  There is no binary dependent code anywhere else.
 334  */
 335
 336 static int load_flat_binary(struct linux_binprm * bprm, struct pt_regs * regs)
 337 {
 338         struct flat_hdr * hdr;
 339         unsigned long textpos = 0, datapos = 0, result;
 340         unsigned long text_len, data_len, bss_len, stack_len, flags;
 341         unsigned long memp = 0, memkasked = 0; /* for finding the brk area */
 342         unsigned long extra, rlim;
 343         unsigned long p = bprm->p;
 344         unsigned long *reloc = 0, *rp;
 345         struct inode *inode;
 346         int i, rev, relocs = 0;
 347         loff_t fpos;
 348
 349         DBG_FLT("BINFMT_FLAT: Loading file: %x\n", bprm->file);
 350
 351         hdr = ((struct flat_hdr *) bprm->buf);          /* exec-header */
 352         inode = bprm->file->f_dentry->d_inode;
 353
 354         text_len  = ntohl(hdr->data_start);
 355         data_len  = ntohl(hdr->data_end) - ntohl(hdr->data_start);
 356         bss_len   = ntohl(hdr->bss_end) - ntohl(hdr->data_end);
 357         stack_len = ntohl(hdr->stack_size);
 358         relocs    = ntohl(hdr->reloc_count);
 359         flags     = ntohl(hdr->flags);
 360         rev       = ntohl(hdr->rev);
 361
 362         /*
 363          * We have to add the size of our arguments to our stack size
 364          * otherwise it's too easy for users to create stack overflows
 365          * by passing in a huge argument list.  And yes,  we have to be
 366          * pedantic and include space for the argv/envp array as it may have
 367          * a lot of entries.
 368          */
 369         #define TOP_OF_ARGS (PAGE_SIZE*MAX_ARG_PAGES-sizeof(void *))
 370         stack_len += TOP_OF_ARGS - bprm->p;             /* the strings */
 371         stack_len += (bprm->argc + 1) * sizeof(char *); /* the argv array */
 372         stack_len += (bprm->envc + 1) * sizeof(char *); /* the envp array */
 373
 374         if (strncmp(hdr->magic, "bFLT", 4) ||
 375                         (rev != FLAT_VERSION && rev != OLD_FLAT_VERSION)) {
 376                 /*
 377                  * because a lot of people do not manage to produce good
 378                  * flat binaries,  we leave this printk to help them realise
 379                  * the problem.  We only print the error if it's
 380                  * not a script file.
 381                  */
 382                 if (strncmp(hdr->magic, "#!", 2))
 383                         printk("BINFMT_FLAT: bad magic/rev (0x%x, need 0x%x)\n",
 384                                         rev, (int) FLAT_VERSION);
 385                 return -ENOEXEC;
 386         }
 387
 388         /*
 389          * fix up the flags for the older format,  there were all kinds
 390          * of endian hacks,  this only works for the simple cases
 391          */
 392         if (rev == OLD_FLAT_VERSION && flags)
 393                 flags = FLAT_FLAG_RAM;
 394
 395 #ifndef CONFIG_BINFMT_ZFLAT
 396         if (flags & (FLAT_FLAG_GZIP|FLAT_FLAG_GZDATA)) {
 397                 printk("Support for ZFLAT executables is not enabled.\n");
 398                 return -ENOEXEC;
 399         }
 400 #endif
 401
 402         /*
 403          * Check initial limits. This avoids letting people circumvent
 404          * size limits imposed on them by creating programs with large
 405          * arrays in the data or bss.
 406          */
 407         rlim = current->rlim[RLIMIT_DATA].rlim_cur;
 408         if (rlim >= RLIM_INFINITY)
 409                 rlim = ~0;
 410         if (data_len + bss_len > rlim)
 411                 return -ENOMEM;
 412
 413         /* Flush all traces of the currently running executable */
 414         result = flush_old_exec(bprm);
 415         if (result)
 416                 return result;
 417
 418         /* OK, This is the point of no return */
 419         set_personality(PER_LINUX);
 420
 421         /*
 422          * there are a couple of cases here,  the separate code/data
 423          * case,  and then the fully copied to RAM case which lumps
 424          * it all together.
 425          */
 426         if ((flags & (FLAT_FLAG_RAM|FLAT_FLAG_GZIP)) == 0) {
 427                 /*
 428                  * this should give us a ROM ptr,  but if it doesn't we don't
 429                  * really care
 430                  */
 431                 DBG_FLT("BINFMT_FLAT: ROM mapping of file (we hope)\n");
 432
 433                 down_write(&current->mm->mmap_sem);
 434                 textpos = do_mmap(bprm->file, 0, text_len, PROT_READ|PROT_EXEC, 0, 0);
 435                 up_write(&current->mm->mmap_sem);
 436                 if (!textpos  || textpos >= (unsigned long) -4096) {
 437                         if (!textpos)
 438                                 textpos = (unsigned long) -ENOMEM;
 439                         printk("Unable to mmap process text, errno %d\n", (int)-textpos);
 440                 }
 441
 442                 extra = max(bss_len + stack_len, relocs * sizeof(unsigned long)),
 443
 444                 down_write(&current->mm->mmap_sem);
 445                 datapos = do_mmap(0, 0, data_len + extra,
 446                                 PROT_READ|PROT_WRITE|PROT_EXEC, 0, 0);
 447                 up_write(&current->mm->mmap_sem);
 448
 449                 if (datapos == 0 || datapos >= (unsigned long)-4096) {
 450                         if (!datapos)
 451                                 datapos = (unsigned long) -ENOMEM;
 452                         printk("Unable to allocate RAM for process data, errno %d\n",
 453                                         (int)-datapos);
 454                         do_munmap(current->mm, textpos, text_len);
 455                         return datapos;
 456                 }
 457
 458                 DBG_FLT("BINFMT_FLAT: Allocated data+bss+stack (%d bytes): %x\n",
 459                                 data_len + bss_len + stack_len, datapos);
 460
 461                 fpos = ntohl(hdr->data_start);
 462 #ifdef CONFIG_BINFMT_ZFLAT
 463                 if (flags & FLAT_FLAG_GZDATA) {
 464                         result = decompress_exec(bprm, fpos, (char *) datapos,
 465                                                  data_len + (relocs * sizeof(unsigned long)), 0);
 466                 } else
 467 #endif
 468                 {
 469                         result = bprm->file->f_op->read(bprm->file,
 470                                         (char *) datapos, data_len + extra, &fpos);
 471                 }
 472                 if (result >= (unsigned long)-4096) {
 473                         printk("Unable to read data+bss, errno %d\n", (int)-result);
 474                         do_munmap(current->mm, textpos, text_len);
 475                         do_munmap(current->mm, datapos, data_len + extra);
 476                         return result;
 477                 }
 478
 479                 reloc = (unsigned long *) (datapos+(ntohl(hdr->reloc_start)-text_len));
 480                 memp = datapos;
 481                 memkasked = data_len + extra;
 482
 483         } else {
 484
 485                 /*
 486                  * calculate the extra space we need to map in
 487                  */
 488
 489                 extra = max(bss_len + stack_len, relocs * sizeof(unsigned long)),
 490
 491                 down_write(&current->mm->mmap_sem);
 492                 textpos = do_mmap(0, 0, text_len + data_len + extra,
 493                                 PROT_READ | PROT_EXEC | PROT_WRITE, 0, 0);
 494                 up_write(&current->mm->mmap_sem);
 495                 if (!textpos  || textpos >= (unsigned long) -4096) {
 496                         if (!textpos)
 497                                 textpos = (unsigned long) -ENOMEM;
 498                         printk("Unable to allocate RAM for process text/data, errno %d\n",
 499                                         (int)-textpos);
 500                 }
 501
 502                 datapos = textpos + ntohl (hdr->data_start);
 503                 reloc = (unsigned long *) (textpos + ntohl(hdr->reloc_start));
 504                 memp = textpos;
 505                 memkasked = text_len + data_len + extra;
 506
 507 #ifdef CONFIG_BINFMT_ZFLAT
 508                 /*
 509                  * load it all in and treat it like a RAM load from now on
 510                  */
 511                 if (flags & FLAT_FLAG_GZIP) {
 512                         result = decompress_exec(bprm, sizeof (struct flat_hdr),
 513                                          (((char *) textpos) + sizeof (struct flat_hdr)),
 514                                          (text_len + data_len + (relocs * sizeof(unsigned long))
 515                                                   - sizeof (struct flat_hdr)),
 516                                          0);
 517                 } else if (flags & FLAT_FLAG_GZDATA) {
 518                         fpos = 0;
 519                         result = bprm->file->f_op->read(bprm->file,
 520                                         (char *) textpos, text_len, &fpos);
 521                         if (result < (unsigned long) -4096)
 522                                 result = decompress_exec(bprm, text_len, (char *) datapos,
 523                                                  data_len + (relocs * sizeof(unsigned long)), 0);
 524                 }
 525                 else
 526 #endif
 527                 {
 528                         fpos = 0;
 529                         result = bprm->file->f_op->read(bprm->file,
 530                                         (char *) textpos, text_len + data_len + extra, &fpos);
 531                 }
 532                 if (result >= (unsigned long)-4096) {
 533                         printk("Unable to read code+data+bss, errno %d\n",(int)-result);
 534                         do_munmap(current->mm, textpos, text_len + data_len + extra);
 535                         return result;
 536                 }
 537         }
 538
 539         DBG_FLT("Mapping is %x, Entry point is %x, data_start is %x\n",
 540                         textpos, ntohl(hdr->entry), ntohl(hdr->data_start));
 541
 542         current->mm->start_code = textpos + sizeof (struct flat_hdr);
 543         current->mm->end_code = textpos + text_len;
 544         current->mm->start_data = datapos;
 545         current->mm->end_data = datapos + data_len;
 546         /*
 547          *      set up the brk stuff (uses any slack left in data/bss/stack allocation
 548          *      We put the brk after the bss (between the bss and stack) like other
 549          *      platforms.
 550          */
 551         current->mm->start_brk = datapos + data_len + bss_len;
 552         current->mm->brk = (current->mm->start_brk + 3) & ~3;
 553         current->mm->context.end_brk = memp + ksize((void *) memp) - stack_len;
 554         current->mm->rss = 0;
 555
 556         DBG_FLT("Load %s: TEXT=%x-%x DATA=%x-%x BSS=%x-%x\n",
 557                 bprm->filename,
 558                 (int) current->mm->start_code, (int) current->mm->end_code,
 559                 (int) current->mm->start_data, (int) current->mm->end_data,
 560                 (int) current->mm->end_data, (int) current->mm->brk);
 561
 562         text_len -= sizeof(struct flat_hdr); /* the real code len */
 563
 564         /*
 565          * We just load the allocations into some temporary memory to
 566          * help simplify all this mumbo jumbo
 567          *
 568          * We've got two different sections of relocation entries.
 569          * The first is the GOT which resides at the begining of the data segment
 570          * and is terminated with a -1.  This one can be relocated in place.
 571          * The second is the extra relocation entries tacked after the image's
 572          * data segment. These require a little more processing as the entry is
 573          * really an offset into the image which contains an offset into the
 574          * image.
 575          */
 576
 577         if (flags & FLAT_FLAG_GOTPIC) {
 578                 for (rp = (unsigned long *)datapos; *rp != 0xffffffff; rp++)
 579                         *rp = calc_reloc(*rp, text_len);
 580         }
 581
 582         /*
 583          * Now run through the relocation entries.
 584          * We've got to be careful here as C++ produces relocatable zero
 585          * entries in the constructor and destructor tables which are then
 586          * tested for being not zero (which will always occur unless we're
 587          * based from address zero).  This causes an endless loop as __start
 588          * is at zero.  The solution used is to not relocate zero addresses.
 589          * This has the negative side effect of not allowing a global data
 590          * reference to be statically initialised to _stext (I've moved
 591          * __start to address 4 so that is okay).
 592          */
 593
 594         if (rev > OLD_FLAT_VERSION) {
 595                 for (i=0; i < relocs; i++) {
 596                         unsigned long addr;
 597
 598                         /* Get the address of the pointer to be
 599                            relocated (of course, the address has to be
 600                            relocated first).  */
 601                         rp = (unsigned long *) calc_reloc(ntohl(reloc[i]), text_len);
 602
 603                         /* Get the pointer's value.  */
 604                         addr = get_unaligned (rp);
 605
 606                         if (addr != 0) {
 607                                 /*
 608                                  * Do the relocation.  PIC relocs in the data section are
 609                                  * already in target order
 610                                  */
 611                                 addr = calc_reloc(
 612                                                 (flags & FLAT_FLAG_GOTPIC) ? addr : ntohl(addr),
 613                                                 text_len);
 614                                 /* Write back the relocated pointer.  */
 615                                 put_unaligned (addr, rp);
 616                         }
 617                 }
 618         } else {
 619                 for (i=0; i < relocs; i++)
 620                         old_reloc(ntohl(reloc[i]));
 621         }
 622
 623         /* zero the BSS,  BRK and stack areas */
 624         memset((void*)(datapos + data_len), 0, bss_len +
 625                         (current->mm->context.end_brk - current->mm->start_brk) +
 626                         stack_len);
 627
 628         compute_creds(bprm);
 629         current->flags &= ~PF_FORKNOEXEC;
 630
 631         flush_icache_range(current->mm->start_code, current->mm->end_code);
 632
 633         set_binfmt(&flat_format);
 634
 635         p = ((current->mm->context.end_brk + stack_len + 3) & ~3) - 4;
 636         DBG_FLT("p=%x\n", p);
 637
 638         /* copy the arg pages onto the stack, this could be more efficient :-) */
 639         for (i = TOP_OF_ARGS - 1; i >= bprm->p; i--)
 640                 * (char *) --p =
 641                         ((char *) page_address(bprm->page[i/PAGE_SIZE]))[i % PAGE_SIZE];
 642
 643         current->mm->start_stack = (unsigned long) create_flat_tables(p, bprm);
 644
 645         DBG_FLT("start_thread(regs=0x%x, entry=0x%x, start_stack=0x%x)\n",
 646                 regs, textpos + ntohl(hdr->entry), current->mm->start_stack);
 647         start_thread(regs,
 648                      textpos + ntohl(hdr->entry),
 649                      current->mm->start_stack);
 650
 651         if (current->ptrace & PT_PTRACED)
 652                 send_sig(SIGTRAP, current, 0);
 653
 654         return 0;
 655 }
 656
 657 static int load_flat_library(struct file *file)
 658 {
 659         return(-ENOEXEC);
 660 }
 661
 662 static int __init init_flat_binfmt(void)
 663 {
 664         return register_binfmt(&flat_format);
 665 }
 666
 667 static void __exit exit_flat_binfmt(void)
 668 {
 669         unregister_binfmt(&flat_format);
 670 }
 671
 672 module_init(init_flat_binfmt);
 673 module_exit(exit_flat_binfmt);