linux-user: add SO_PEERCRED support for getsockopt
[qemu.git] / 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, 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((void *)((unsigned long)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 }