i386: host_vendor_fms() helper function
[qemu/kevin.git] / linux-user / flatload.c
bloba35a560904917d086e52b97c8294e1d3e2d52e55
1 /****************************************************************************/
2 /*
3 * QEMU bFLT binary loader. Based on linux/fs/binfmt_flat.c
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.
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.
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/>.
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:
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)
32 /* ??? ZFLAT and shared library support is currently disabled. */
34 /****************************************************************************/
36 #include "qemu/osdep.h"
38 #include "qemu.h"
39 #include "flat.h"
40 #include "target_flat.h"
42 //#define DEBUG
44 #ifdef DEBUG
45 #define DBG_FLT(...) printf(__VA_ARGS__)
46 #else
47 #define DBG_FLT(...)
48 #endif
50 #define RELOC_FAILED 0xff00ff01 /* Relocation incorrect somewhere */
51 #define UNLOADED_LIB 0x7ff000ff /* Placeholder for unused library */
53 struct lib_info {
54 abi_ulong start_code; /* Start of text segment */
55 abi_ulong start_data; /* Start of data segment */
56 abi_ulong end_data; /* Start of bss section */
57 abi_ulong start_brk; /* End of data segment */
58 abi_ulong text_len; /* Length of text segment */
59 abi_ulong entry; /* Start address for this module */
60 abi_ulong build_date; /* When this one was compiled */
61 short loaded; /* Has this library been loaded? */
64 #ifdef CONFIG_BINFMT_SHARED_FLAT
65 static int load_flat_shared_library(int id, struct lib_info *p);
66 #endif
68 struct linux_binprm;
70 /****************************************************************************/
72 * create_flat_tables() parses the env- and arg-strings in new user
73 * memory and creates the pointer tables from them, and puts their
74 * addresses on the "stack", returning the new stack pointer value.
77 /* Push a block of strings onto the guest stack. */
78 static abi_ulong copy_strings(abi_ulong p, int n, char **s)
80 int len;
82 while (n-- > 0) {
83 len = strlen(s[n]) + 1;
84 p -= len;
85 memcpy_to_target(p, s[n], len);
88 return p;
91 static int target_pread(int fd, abi_ulong ptr, abi_ulong len,
92 abi_ulong offset)
94 void *buf;
95 int ret;
97 buf = lock_user(VERIFY_WRITE, ptr, len, 0);
98 if (!buf) {
99 return -EFAULT;
101 ret = pread(fd, buf, len, offset);
102 if (ret < 0) {
103 ret = -errno;
105 unlock_user(buf, ptr, len);
106 return ret;
108 /****************************************************************************/
110 #ifdef CONFIG_BINFMT_ZFLAT
112 #include <linux/zlib.h>
114 #define LBUFSIZE 4000
116 /* gzip flag byte */
117 #define ASCII_FLAG 0x01 /* bit 0 set: file probably ASCII text */
118 #define CONTINUATION 0x02 /* bit 1 set: continuation of multi-part gzip file */
119 #define EXTRA_FIELD 0x04 /* bit 2 set: extra field present */
120 #define ORIG_NAME 0x08 /* bit 3 set: original file name present */
121 #define COMMENT 0x10 /* bit 4 set: file comment present */
122 #define ENCRYPTED 0x20 /* bit 5 set: file is encrypted */
123 #define RESERVED 0xC0 /* bit 6,7: reserved */
125 static int decompress_exec(
126 struct linux_binprm *bprm,
127 unsigned long offset,
128 char *dst,
129 long len,
130 int fd)
132 unsigned char *buf;
133 z_stream strm;
134 loff_t fpos;
135 int ret, retval;
137 DBG_FLT("decompress_exec(offset=%x,buf=%x,len=%x)\n",(int)offset, (int)dst, (int)len);
139 memset(&strm, 0, sizeof(strm));
140 strm.workspace = kmalloc(zlib_inflate_workspacesize(), GFP_KERNEL);
141 if (strm.workspace == NULL) {
142 DBG_FLT("binfmt_flat: no memory for decompress workspace\n");
143 return -ENOMEM;
145 buf = kmalloc(LBUFSIZE, GFP_KERNEL);
146 if (buf == NULL) {
147 DBG_FLT("binfmt_flat: no memory for read buffer\n");
148 retval = -ENOMEM;
149 goto out_free;
152 /* Read in first chunk of data and parse gzip header. */
153 fpos = offset;
154 ret = bprm->file->f_op->read(bprm->file, buf, LBUFSIZE, &fpos);
156 strm.next_in = buf;
157 strm.avail_in = ret;
158 strm.total_in = 0;
160 retval = -ENOEXEC;
162 /* Check minimum size -- gzip header */
163 if (ret < 10) {
164 DBG_FLT("binfmt_flat: file too small?\n");
165 goto out_free_buf;
168 /* Check gzip magic number */
169 if ((buf[0] != 037) || ((buf[1] != 0213) && (buf[1] != 0236))) {
170 DBG_FLT("binfmt_flat: unknown compression magic?\n");
171 goto out_free_buf;
174 /* Check gzip method */
175 if (buf[2] != 8) {
176 DBG_FLT("binfmt_flat: unknown compression method?\n");
177 goto out_free_buf;
179 /* Check gzip flags */
180 if ((buf[3] & ENCRYPTED) || (buf[3] & CONTINUATION) ||
181 (buf[3] & RESERVED)) {
182 DBG_FLT("binfmt_flat: unknown flags?\n");
183 goto out_free_buf;
186 ret = 10;
187 if (buf[3] & EXTRA_FIELD) {
188 ret += 2 + buf[10] + (buf[11] << 8);
189 if (unlikely(LBUFSIZE == ret)) {
190 DBG_FLT("binfmt_flat: buffer overflow (EXTRA)?\n");
191 goto out_free_buf;
194 if (buf[3] & ORIG_NAME) {
195 for (; ret < LBUFSIZE && (buf[ret] != 0); ret++)
197 if (unlikely(LBUFSIZE == ret)) {
198 DBG_FLT("binfmt_flat: buffer overflow (ORIG_NAME)?\n");
199 goto out_free_buf;
202 if (buf[3] & COMMENT) {
203 for (; ret < LBUFSIZE && (buf[ret] != 0); ret++)
205 if (unlikely(LBUFSIZE == ret)) {
206 DBG_FLT("binfmt_flat: buffer overflow (COMMENT)?\n");
207 goto out_free_buf;
211 strm.next_in += ret;
212 strm.avail_in -= ret;
214 strm.next_out = dst;
215 strm.avail_out = len;
216 strm.total_out = 0;
218 if (zlib_inflateInit2(&strm, -MAX_WBITS) != Z_OK) {
219 DBG_FLT("binfmt_flat: zlib init failed?\n");
220 goto out_free_buf;
223 while ((ret = zlib_inflate(&strm, Z_NO_FLUSH)) == Z_OK) {
224 ret = bprm->file->f_op->read(bprm->file, buf, LBUFSIZE, &fpos);
225 if (ret <= 0)
226 break;
227 if (ret >= (unsigned long) -4096)
228 break;
229 len -= ret;
231 strm.next_in = buf;
232 strm.avail_in = ret;
233 strm.total_in = 0;
236 if (ret < 0) {
237 DBG_FLT("binfmt_flat: decompression failed (%d), %s\n",
238 ret, strm.msg);
239 goto out_zlib;
242 retval = 0;
243 out_zlib:
244 zlib_inflateEnd(&strm);
245 out_free_buf:
246 kfree(buf);
247 out_free:
248 kfree(strm.workspace);
249 out:
250 return retval;
253 #endif /* CONFIG_BINFMT_ZFLAT */
255 /****************************************************************************/
257 static abi_ulong
258 calc_reloc(abi_ulong r, struct lib_info *p, int curid, int internalp)
260 abi_ulong addr;
261 int id;
262 abi_ulong start_brk;
263 abi_ulong start_data;
264 abi_ulong text_len;
265 abi_ulong start_code;
267 #ifdef CONFIG_BINFMT_SHARED_FLAT
268 #error needs checking
269 if (r == 0)
270 id = curid; /* Relocs of 0 are always self referring */
271 else {
272 id = (r >> 24) & 0xff; /* Find ID for this reloc */
273 r &= 0x00ffffff; /* Trim ID off here */
275 if (id >= MAX_SHARED_LIBS) {
276 fprintf(stderr, "BINFMT_FLAT: reference 0x%x to shared library %d\n",
277 (unsigned) r, id);
278 goto failed;
280 if (curid != id) {
281 if (internalp) {
282 fprintf(stderr, "BINFMT_FLAT: reloc address 0x%x not "
283 "in same module (%d != %d)\n",
284 (unsigned) r, curid, id);
285 goto failed;
286 } else if ( ! p[id].loaded &&
287 load_flat_shared_library(id, p) > (unsigned long) -4096) {
288 fprintf(stderr, "BINFMT_FLAT: failed to load library %d\n", id);
289 goto failed;
291 /* Check versioning information (i.e. time stamps) */
292 if (p[id].build_date && p[curid].build_date
293 && p[curid].build_date < p[id].build_date) {
294 fprintf(stderr, "BINFMT_FLAT: library %d is younger than %d\n",
295 id, curid);
296 goto failed;
299 #else
300 id = 0;
301 #endif
303 start_brk = p[id].start_brk;
304 start_data = p[id].start_data;
305 start_code = p[id].start_code;
306 text_len = p[id].text_len;
308 if (!flat_reloc_valid(r, start_brk - start_data + text_len)) {
309 fprintf(stderr, "BINFMT_FLAT: reloc outside program 0x%x "
310 "(0 - 0x%x/0x%x)\n",
311 (int) r,(int)(start_brk-start_code),(int)text_len);
312 goto failed;
315 if (r < text_len) /* In text segment */
316 addr = r + start_code;
317 else /* In data segment */
318 addr = r - text_len + start_data;
320 /* Range checked already above so doing the range tests is redundant...*/
321 return(addr);
323 failed:
324 abort();
325 return RELOC_FAILED;
328 /****************************************************************************/
330 /* ??? This does not handle endianness correctly. */
331 static void old_reloc(struct lib_info *libinfo, uint32_t rl)
333 #ifdef DEBUG
334 const char *segment[] = { "TEXT", "DATA", "BSS", "*UNKNOWN*" };
335 #endif
336 uint32_t *ptr;
337 uint32_t offset;
338 int reloc_type;
340 offset = rl & 0x3fffffff;
341 reloc_type = rl >> 30;
342 /* ??? How to handle this? */
343 #if defined(CONFIG_COLDFIRE)
344 ptr = (uint32_t *) ((unsigned long) libinfo->start_code + offset);
345 #else
346 ptr = (uint32_t *) ((unsigned long) libinfo->start_data + offset);
347 #endif
349 #ifdef DEBUG
350 fprintf(stderr, "Relocation of variable at DATASEG+%x "
351 "(address %p, currently %x) into segment %s\n",
352 offset, ptr, (int)*ptr, segment[reloc_type]);
353 #endif
355 switch (reloc_type) {
356 case OLD_FLAT_RELOC_TYPE_TEXT:
357 *ptr += libinfo->start_code;
358 break;
359 case OLD_FLAT_RELOC_TYPE_DATA:
360 *ptr += libinfo->start_data;
361 break;
362 case OLD_FLAT_RELOC_TYPE_BSS:
363 *ptr += libinfo->end_data;
364 break;
365 default:
366 fprintf(stderr, "BINFMT_FLAT: Unknown relocation type=%x\n",
367 reloc_type);
368 break;
370 DBG_FLT("Relocation became %x\n", (int)*ptr);
373 /****************************************************************************/
375 static int load_flat_file(struct linux_binprm * bprm,
376 struct lib_info *libinfo, int id, abi_ulong *extra_stack)
378 struct flat_hdr * hdr;
379 abi_ulong textpos = 0, datapos = 0;
380 abi_long result;
381 abi_ulong realdatastart = 0;
382 abi_ulong text_len, data_len, bss_len, stack_len, flags;
383 abi_ulong extra;
384 abi_ulong reloc = 0, rp;
385 int i, rev, relocs = 0;
386 abi_ulong fpos;
387 abi_ulong start_code;
388 abi_ulong indx_len;
390 hdr = ((struct flat_hdr *) bprm->buf); /* exec-header */
392 text_len = ntohl(hdr->data_start);
393 data_len = ntohl(hdr->data_end) - ntohl(hdr->data_start);
394 bss_len = ntohl(hdr->bss_end) - ntohl(hdr->data_end);
395 stack_len = ntohl(hdr->stack_size);
396 if (extra_stack) {
397 stack_len += *extra_stack;
398 *extra_stack = stack_len;
400 relocs = ntohl(hdr->reloc_count);
401 flags = ntohl(hdr->flags);
402 rev = ntohl(hdr->rev);
404 DBG_FLT("BINFMT_FLAT: Loading file: %s\n", bprm->filename);
406 if (rev != FLAT_VERSION && rev != OLD_FLAT_VERSION) {
407 fprintf(stderr, "BINFMT_FLAT: bad magic/rev (0x%x, need 0x%x)\n",
408 rev, (int) FLAT_VERSION);
409 return -ENOEXEC;
412 /* Don't allow old format executables to use shared libraries */
413 if (rev == OLD_FLAT_VERSION && id != 0) {
414 fprintf(stderr, "BINFMT_FLAT: shared libraries are not available\n");
415 return -ENOEXEC;
419 * fix up the flags for the older format, there were all kinds
420 * of endian hacks, this only works for the simple cases
422 if (rev == OLD_FLAT_VERSION && flat_old_ram_flag(flags))
423 flags = FLAT_FLAG_RAM;
425 #ifndef CONFIG_BINFMT_ZFLAT
426 if (flags & (FLAT_FLAG_GZIP|FLAT_FLAG_GZDATA)) {
427 fprintf(stderr, "Support for ZFLAT executables is not enabled\n");
428 return -ENOEXEC;
430 #endif
433 * calculate the extra space we need to map in
435 extra = relocs * sizeof(abi_ulong);
436 if (extra < bss_len + stack_len)
437 extra = bss_len + stack_len;
439 /* Add space for library base pointers. Make sure this does not
440 misalign the doesn't misalign the data segment. */
441 indx_len = MAX_SHARED_LIBS * sizeof(abi_ulong);
442 indx_len = (indx_len + 15) & ~(abi_ulong)15;
445 * there are a couple of cases here, the separate code/data
446 * case, and then the fully copied to RAM case which lumps
447 * it all together.
449 if ((flags & (FLAT_FLAG_RAM|FLAT_FLAG_GZIP)) == 0) {
451 * this should give us a ROM ptr, but if it doesn't we don't
452 * really care
454 DBG_FLT("BINFMT_FLAT: ROM mapping of file (we hope)\n");
456 textpos = target_mmap(0, text_len, PROT_READ|PROT_EXEC,
457 MAP_PRIVATE, bprm->fd, 0);
458 if (textpos == -1) {
459 fprintf(stderr, "Unable to mmap process text\n");
460 return -1;
463 realdatastart = target_mmap(0, data_len + extra + indx_len,
464 PROT_READ|PROT_WRITE|PROT_EXEC,
465 MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
467 if (realdatastart == -1) {
468 fprintf(stderr, "Unable to allocate RAM for process data\n");
469 return realdatastart;
471 datapos = realdatastart + indx_len;
473 DBG_FLT("BINFMT_FLAT: Allocated data+bss+stack (%d bytes): %x\n",
474 (int)(data_len + bss_len + stack_len), (int)datapos);
476 fpos = ntohl(hdr->data_start);
477 #ifdef CONFIG_BINFMT_ZFLAT
478 if (flags & FLAT_FLAG_GZDATA) {
479 result = decompress_exec(bprm, fpos, (char *) datapos,
480 data_len + (relocs * sizeof(abi_ulong)))
481 } else
482 #endif
484 result = target_pread(bprm->fd, datapos,
485 data_len + (relocs * sizeof(abi_ulong)),
486 fpos);
488 if (result < 0) {
489 fprintf(stderr, "Unable to read data+bss\n");
490 return result;
493 reloc = datapos + (ntohl(hdr->reloc_start) - text_len);
495 } else {
497 textpos = target_mmap(0, text_len + data_len + extra + indx_len,
498 PROT_READ | PROT_EXEC | PROT_WRITE,
499 MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
500 if (textpos == -1 ) {
501 fprintf(stderr, "Unable to allocate RAM for process text/data\n");
502 return -1;
505 realdatastart = textpos + ntohl(hdr->data_start);
506 datapos = realdatastart + indx_len;
507 reloc = (textpos + ntohl(hdr->reloc_start) + indx_len);
509 #ifdef CONFIG_BINFMT_ZFLAT
510 #error code needs checking
512 * load it all in and treat it like a RAM load from now on
514 if (flags & FLAT_FLAG_GZIP) {
515 result = decompress_exec(bprm, sizeof (struct flat_hdr),
516 (((char *) textpos) + sizeof (struct flat_hdr)),
517 (text_len + data_len + (relocs * sizeof(unsigned long))
518 - sizeof (struct flat_hdr)),
520 memmove((void *) datapos, (void *) realdatastart,
521 data_len + (relocs * sizeof(unsigned long)));
522 } else if (flags & FLAT_FLAG_GZDATA) {
523 fpos = 0;
524 result = bprm->file->f_op->read(bprm->file,
525 (char *) textpos, text_len, &fpos);
526 if (result < (unsigned long) -4096)
527 result = decompress_exec(bprm, text_len, (char *) datapos,
528 data_len + (relocs * sizeof(unsigned long)), 0);
530 else
531 #endif
533 result = target_pread(bprm->fd, textpos,
534 text_len, 0);
535 if (result >= 0) {
536 result = target_pread(bprm->fd, datapos,
537 data_len + (relocs * sizeof(abi_ulong)),
538 ntohl(hdr->data_start));
541 if (result < 0) {
542 fprintf(stderr, "Unable to read code+data+bss\n");
543 return result;
547 DBG_FLT("Mapping is 0x%x, Entry point is 0x%x, data_start is 0x%x\n",
548 (int)textpos, 0x00ffffff&ntohl(hdr->entry),
549 ntohl(hdr->data_start));
551 /* The main program needs a little extra setup in the task structure */
552 start_code = textpos + sizeof (struct flat_hdr);
554 DBG_FLT("%s %s: TEXT=%x-%x DATA=%x-%x BSS=%x-%x\n",
555 id ? "Lib" : "Load", bprm->filename,
556 (int) start_code, (int) (textpos + text_len),
557 (int) datapos,
558 (int) (datapos + data_len),
559 (int) (datapos + data_len),
560 (int) (((datapos + data_len + bss_len) + 3) & ~3));
562 text_len -= sizeof(struct flat_hdr); /* the real code len */
564 /* Store the current module values into the global library structure */
565 libinfo[id].start_code = start_code;
566 libinfo[id].start_data = datapos;
567 libinfo[id].end_data = datapos + data_len;
568 libinfo[id].start_brk = datapos + data_len + bss_len;
569 libinfo[id].text_len = text_len;
570 libinfo[id].loaded = 1;
571 libinfo[id].entry = (0x00ffffff & ntohl(hdr->entry)) + textpos;
572 libinfo[id].build_date = ntohl(hdr->build_date);
575 * We just load the allocations into some temporary memory to
576 * help simplify all this mumbo jumbo
578 * We've got two different sections of relocation entries.
579 * The first is the GOT which resides at the beginning of the data segment
580 * and is terminated with a -1. This one can be relocated in place.
581 * The second is the extra relocation entries tacked after the image's
582 * data segment. These require a little more processing as the entry is
583 * really an offset into the image which contains an offset into the
584 * image.
586 if (flags & FLAT_FLAG_GOTPIC) {
587 rp = datapos;
588 while (1) {
589 abi_ulong addr;
590 if (get_user_ual(addr, rp))
591 return -EFAULT;
592 if (addr == -1)
593 break;
594 if (addr) {
595 addr = calc_reloc(addr, libinfo, id, 0);
596 if (addr == RELOC_FAILED)
597 return -ENOEXEC;
598 if (put_user_ual(addr, rp))
599 return -EFAULT;
601 rp += sizeof(abi_ulong);
606 * Now run through the relocation entries.
607 * We've got to be careful here as C++ produces relocatable zero
608 * entries in the constructor and destructor tables which are then
609 * tested for being not zero (which will always occur unless we're
610 * based from address zero). This causes an endless loop as __start
611 * is at zero. The solution used is to not relocate zero addresses.
612 * This has the negative side effect of not allowing a global data
613 * reference to be statically initialised to _stext (I've moved
614 * __start to address 4 so that is okay).
616 if (rev > OLD_FLAT_VERSION) {
617 abi_ulong persistent = 0;
618 for (i = 0; i < relocs; i++) {
619 abi_ulong addr, relval;
621 /* Get the address of the pointer to be
622 relocated (of course, the address has to be
623 relocated first). */
624 if (get_user_ual(relval, reloc + i * sizeof(abi_ulong)))
625 return -EFAULT;
626 relval = ntohl(relval);
627 if (flat_set_persistent(relval, &persistent))
628 continue;
629 addr = flat_get_relocate_addr(relval);
630 rp = calc_reloc(addr, libinfo, id, 1);
631 if (rp == RELOC_FAILED)
632 return -ENOEXEC;
634 /* Get the pointer's value. */
635 if (get_user_ual(addr, rp))
636 return -EFAULT;
637 addr = flat_get_addr_from_rp(addr, relval, flags, &persistent);
638 if (addr != 0) {
640 * Do the relocation. PIC relocs in the data section are
641 * already in target order
643 if ((flags & FLAT_FLAG_GOTPIC) == 0)
644 addr = ntohl(addr);
645 addr = calc_reloc(addr, libinfo, id, 0);
646 if (addr == RELOC_FAILED)
647 return -ENOEXEC;
649 /* Write back the relocated pointer. */
650 if (flat_put_addr_at_rp(rp, addr, relval))
651 return -EFAULT;
654 } else {
655 for (i = 0; i < relocs; i++) {
656 abi_ulong relval;
657 if (get_user_ual(relval, reloc + i * sizeof(abi_ulong)))
658 return -EFAULT;
659 old_reloc(&libinfo[0], relval);
663 /* zero the BSS. */
664 memset(g2h(datapos + data_len), 0, bss_len);
666 return 0;
670 /****************************************************************************/
671 #ifdef CONFIG_BINFMT_SHARED_FLAT
674 * Load a shared library into memory. The library gets its own data
675 * segment (including bss) but not argv/argc/environ.
678 static int load_flat_shared_library(int id, struct lib_info *libs)
680 struct linux_binprm bprm;
681 int res;
682 char buf[16];
684 /* Create the file name */
685 sprintf(buf, "/lib/lib%d.so", id);
687 /* Open the file up */
688 bprm.filename = buf;
689 bprm.file = open_exec(bprm.filename);
690 res = PTR_ERR(bprm.file);
691 if (IS_ERR(bprm.file))
692 return res;
694 res = prepare_binprm(&bprm);
696 if (res <= (unsigned long)-4096)
697 res = load_flat_file(&bprm, libs, id, NULL);
698 if (bprm.file) {
699 allow_write_access(bprm.file);
700 fput(bprm.file);
701 bprm.file = NULL;
703 return(res);
706 #endif /* CONFIG_BINFMT_SHARED_FLAT */
708 int load_flt_binary(struct linux_binprm *bprm, struct image_info *info)
710 struct lib_info libinfo[MAX_SHARED_LIBS];
711 abi_ulong p;
712 abi_ulong stack_len;
713 abi_ulong start_addr;
714 abi_ulong sp;
715 int res;
716 int i, j;
718 memset(libinfo, 0, sizeof(libinfo));
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.
726 stack_len = 0;
727 for (i = 0; i < bprm->argc; ++i) {
728 /* the argv strings */
729 stack_len += strlen(bprm->argv[i]);
731 for (i = 0; i < bprm->envc; ++i) {
732 /* the envp strings */
733 stack_len += strlen(bprm->envp[i]);
735 stack_len += (bprm->argc + 1) * 4; /* the argv array */
736 stack_len += (bprm->envc + 1) * 4; /* the envp array */
739 res = load_flat_file(bprm, libinfo, 0, &stack_len);
740 if (res > (unsigned long)-4096)
741 return res;
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,
755 return -EFAULT;
760 p = ((libinfo[0].start_brk + stack_len + 3) & ~3) - 4;
761 DBG_FLT("p=%x\n", (int)p);
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());
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).
782 start_addr = libinfo[0].entry;
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;
795 #endif
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;
809 DBG_FLT("start_thread(entry=0x%x, start_stack=0x%x)\n",
810 (int)info->entry, (int)info->start_stack);
812 return 0;