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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
    abi_ulong start_code;       /* Start of text segment */
67
    abi_ulong start_data;       /* Start of data segment */
68
    abi_ulong end_data;         /* Start of bss section */
69
    abi_ulong start_brk;        /* End of data segment */
70
    abi_ulong text_len;                /* Length of text segment */
71
    abi_ulong entry;                /* Start address for this module */
72
    abi_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 abi_ulong copy_strings(abi_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, abi_ulong ptr, abi_ulong len,
106
                 abi_ulong offset)
107
{
108
    void *buf;
109
    int ret;
110

    
111
    buf = lock_user(VERIFY_WRITE, 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 abi_ulong
266
calc_reloc(abi_ulong r, struct lib_info *p, int curid, int internalp)
267
{
268
    abi_ulong addr;
269
    int id;
270
    abi_ulong start_brk;
271
    abi_ulong start_data;
272
    abi_ulong text_len;
273
    abi_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, abi_ulong *extra_stack)
385
{
386
    struct flat_hdr * hdr;
387
    abi_ulong textpos = 0, datapos = 0, result;
388
    abi_ulong realdatastart = 0;
389
    abi_ulong text_len, data_len, bss_len, stack_len, flags;
390
    abi_ulong memp = 0; /* for finding the brk area */
391
    abi_ulong extra;
392
    abi_ulong reloc = 0, rp;
393
    int i, rev, relocs = 0;
394
    abi_ulong fpos;
395
    abi_ulong start_code, end_code;
396
    abi_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(abi_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(abi_ulong);
450
    indx_len = (indx_len + 15) & ~(abi_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(abi_ulong)))
489
        } else
490
#endif
491
        {
492
            result = target_pread(bprm->fd, datapos,
493
                                  data_len + (relocs * sizeof(abi_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(abi_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
            abi_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(abi_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
            abi_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 (abi_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
            abi_ulong relval;
661
            relval = tgetl(reloc + i * sizeof (abi_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
    abi_ulong p = bprm->p;
716
    abi_ulong stack_len;
717
    abi_ulong start_addr;
718
    abi_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
            abi_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 & ~(abi_ulong)(sizeof(abi_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(abi_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
}