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Merge branch 'sas-fixes' of master.kernel.org:/pub/scm/linux/kernel/git/jgarzik/misc-2.6
[net-next-2.6.git] / fs / binfmt_flat.c
CommitLineData
1da177e4
LT		 1/****************************************************************************/
2/*
3 * linux/fs/binfmt_flat.c
4 *
5 * Copyright (C) 2000-2003 David McCullough <davidm@snapgear.com>
6 * Copyright (C) 2002 Greg Ungerer <gerg@snapgear.com>
7 * Copyright (C) 2002 SnapGear, by Paul Dale <pauli@snapgear.com>
8 * Copyright (C) 2000, 2001 Lineo, by David McCullough <davidm@lineo.com>
9 * based heavily on:
10 *
11 * linux/fs/binfmt_aout.c:
12 * Copyright (C) 1991, 1992, 1996 Linus Torvalds
13 * linux/fs/binfmt_flat.c for 2.0 kernel
14 * Copyright (C) 1998 Kenneth Albanowski <kjahds@kjahds.com>
15 * JAN/99 -- coded full program relocation (gerg@snapgear.com)
16 */
17
18#include <linux/module.h>
1da177e4
LT		 19#include <linux/kernel.h>
20#include <linux/sched.h>
21#include <linux/mm.h>
22#include <linux/mman.h>
23#include <linux/a.out.h>
24#include <linux/errno.h>
25#include <linux/signal.h>
26#include <linux/string.h>
27#include <linux/fs.h>
28#include <linux/file.h>
29#include <linux/stat.h>
30#include <linux/fcntl.h>
31#include <linux/ptrace.h>
32#include <linux/user.h>
33#include <linux/slab.h>
34#include <linux/binfmts.h>
35#include <linux/personality.h>
36#include <linux/init.h>
37#include <linux/flat.h>
1ad3dcc0 38#include <linux/syscalls.h>
1da177e4
LT		 39
40#include <asm/byteorder.h>
41#include <asm/system.h>
42#include <asm/uaccess.h>
43#include <asm/unaligned.h>
44#include <asm/cacheflush.h>
45
46/****************************************************************************/
47
48#if 0
49#define DEBUG 1
50#endif
51
52#ifdef DEBUG
53#define DBG_FLT(a...) printk(a)
54#else
55#define DBG_FLT(a...)
56#endif
57
58#define RELOC_FAILED 0xff00ff01 /* Relocation incorrect somewhere */
59#define UNLOADED_LIB 0x7ff000ff /* Placeholder for unused library */
60
61struct lib_info {
62 struct {
63 unsigned long start_code; /* Start of text segment */
64 unsigned long start_data; /* Start of data segment */
65 unsigned long start_brk; /* End of data segment */
66 unsigned long text_len; /* Length of text segment */
67 unsigned long entry; /* Start address for this module */
68 unsigned long build_date; /* When this one was compiled */
69 short loaded; /* Has this library been loaded? */
70 } lib_list[MAX_SHARED_LIBS];
71};
72
73#ifdef CONFIG_BINFMT_SHARED_FLAT
74static int load_flat_shared_library(int id, struct lib_info *p);
75#endif
76
77static int load_flat_binary(struct linux_binprm *, struct pt_regs * regs);
78static int flat_core_dump(long signr, struct pt_regs * regs, struct file *file);
79
1da177e4
LT		 80static struct linux_binfmt flat_format = {
81 .module = THIS_MODULE,
82 .load_binary = load_flat_binary,
83 .core_dump = flat_core_dump,
84 .min_coredump = PAGE_SIZE
85};
86
87/****************************************************************************/
88/*
89 * Routine writes a core dump image in the current directory.
90 * Currently only a stub-function.
91 */
92
93static int flat_core_dump(long signr, struct pt_regs * regs, struct file *file)
94{
95 printk("Process %s:%d received signr %d and should have core dumped\n",
96 current->comm, current->pid, (int) signr);
97 return(1);
98}
99
100/****************************************************************************/
101/*
102 * create_flat_tables() parses the env- and arg-strings in new user
103 * memory and creates the pointer tables from them, and puts their
104 * addresses on the "stack", returning the new stack pointer value.
105 */
106
107static unsigned long create_flat_tables(
108 unsigned long pp,
109 struct linux_binprm * bprm)
110{
111 unsigned long *argv,*envp;
112 unsigned long * sp;
113 char * p = (char*)pp;
114 int argc = bprm->argc;
115 int envc = bprm->envc;
116 char dummy;
117
118 sp = (unsigned long *) ((-(unsigned long)sizeof(char *))&(unsigned long) p);
119
120 sp -= envc+1;
121 envp = sp;
122 sp -= argc+1;
123 argv = sp;
124
125 flat_stack_align(sp);
126 if (flat_argvp_envp_on_stack()) {
127 --sp; put_user((unsigned long) envp, sp);
128 --sp; put_user((unsigned long) argv, sp);
129 }
130
131 put_user(argc,--sp);
132 current->mm->arg_start = (unsigned long) p;
133 while (argc-->0) {
134 put_user((unsigned long) p, argv++);
135 do {
136 get_user(dummy, p); p++;
137 } while (dummy);
138 }
139 put_user((unsigned long) NULL, argv);
140 current->mm->arg_end = current->mm->env_start = (unsigned long) p;
141 while (envc-->0) {
142 put_user((unsigned long)p, envp); envp++;
143 do {
144 get_user(dummy, p); p++;
145 } while (dummy);
146 }
147 put_user((unsigned long) NULL, envp);
148 current->mm->env_end = (unsigned long) p;
149 return (unsigned long)sp;
150}
151
152/****************************************************************************/
153
154#ifdef CONFIG_BINFMT_ZFLAT
155
156#include <linux/zlib.h>
157
158#define LBUFSIZE 4000
159
160/* gzip flag byte */
161#define ASCII_FLAG 0x01 /* bit 0 set: file probably ASCII text */
162#define CONTINUATION 0x02 /* bit 1 set: continuation of multi-part gzip file */
163#define EXTRA_FIELD 0x04 /* bit 2 set: extra field present */
164#define ORIG_NAME 0x08 /* bit 3 set: original file name present */
165#define COMMENT 0x10 /* bit 4 set: file comment present */
166#define ENCRYPTED 0x20 /* bit 5 set: file is encrypted */
167#define RESERVED 0xC0 /* bit 6,7: reserved */
168
169static int decompress_exec(
170 struct linux_binprm *bprm,
171 unsigned long offset,
172 char *dst,
173 long len,
174 int fd)
175{
176 unsigned char *buf;
177 z_stream strm;
178 loff_t fpos;
179 int ret, retval;
180
181 DBG_FLT("decompress_exec(offset=%x,buf=%x,len=%x)\n",(int)offset, (int)dst, (int)len);
182
183 memset(&strm, 0, sizeof(strm));
184 strm.workspace = kmalloc(zlib_inflate_workspacesize(), GFP_KERNEL);
185 if (strm.workspace == NULL) {
186 DBG_FLT("binfmt_flat: no memory for decompress workspace\n");
187 return -ENOMEM;
188 }
189 buf = kmalloc(LBUFSIZE, GFP_KERNEL);
190 if (buf == NULL) {
191 DBG_FLT("binfmt_flat: no memory for read buffer\n");
192 retval = -ENOMEM;
193 goto out_free;
194 }
195
196 /* Read in first chunk of data and parse gzip header. */
197 fpos = offset;
198 ret = bprm->file->f_op->read(bprm->file, buf, LBUFSIZE, &fpos);
199
200 strm.next_in = buf;
201 strm.avail_in = ret;
202 strm.total_in = 0;
203
204 retval = -ENOEXEC;
205
206 /* Check minimum size -- gzip header */
207 if (ret < 10) {
208 DBG_FLT("binfmt_flat: file too small?\n");
209 goto out_free_buf;
210 }
211
212 /* Check gzip magic number */
213 if ((buf[0] != 037) || ((buf[1] != 0213) && (buf[1] != 0236))) {
214 DBG_FLT("binfmt_flat: unknown compression magic?\n");
215 goto out_free_buf;
216 }
217
218 /* Check gzip method */
219 if (buf[2] != 8) {
220 DBG_FLT("binfmt_flat: unknown compression method?\n");
221 goto out_free_buf;
222 }
223 /* Check gzip flags */
224 if ((buf[3] & ENCRYPTED) || (buf[3] & CONTINUATION) ||
225 (buf[3] & RESERVED)) {
226 DBG_FLT("binfmt_flat: unknown flags?\n");
227 goto out_free_buf;
228 }
229
230 ret = 10;
231 if (buf[3] & EXTRA_FIELD) {
232 ret += 2 + buf[10] + (buf[11] << 8);
233 if (unlikely(LBUFSIZE == ret)) {
234 DBG_FLT("binfmt_flat: buffer overflow (EXTRA)?\n");
235 goto out_free_buf;
236 }
237 }
238 if (buf[3] & ORIG_NAME) {
239 for (; ret < LBUFSIZE && (buf[ret] != 0); ret++)
240 ;
241 if (unlikely(LBUFSIZE == ret)) {
242 DBG_FLT("binfmt_flat: buffer overflow (ORIG_NAME)?\n");
243 goto out_free_buf;
244 }
245 }
246 if (buf[3] & COMMENT) {
247 for (; ret < LBUFSIZE && (buf[ret] != 0); ret++)
248 ;
249 if (unlikely(LBUFSIZE == ret)) {
250 DBG_FLT("binfmt_flat: buffer overflow (COMMENT)?\n");
251 goto out_free_buf;
252 }
253 }
254
255 strm.next_in += ret;
256 strm.avail_in -= ret;
257
258 strm.next_out = dst;
259 strm.avail_out = len;
260 strm.total_out = 0;
261
262 if (zlib_inflateInit2(&strm, -MAX_WBITS) != Z_OK) {
263 DBG_FLT("binfmt_flat: zlib init failed?\n");
264 goto out_free_buf;
265 }
266
267 while ((ret = zlib_inflate(&strm, Z_NO_FLUSH)) == Z_OK) {
268 ret = bprm->file->f_op->read(bprm->file, buf, LBUFSIZE, &fpos);
269 if (ret <= 0)
270 break;
271 if (ret >= (unsigned long) -4096)
272 break;
273 len -= ret;
274
275 strm.next_in = buf;
276 strm.avail_in = ret;
277 strm.total_in = 0;
278 }
279
280 if (ret < 0) {
281 DBG_FLT("binfmt_flat: decompression failed (%d), %s\n",
282 ret, strm.msg);
283 goto out_zlib;
284 }
285
286 retval = 0;
287out_zlib:
288 zlib_inflateEnd(&strm);
289out_free_buf:
290 kfree(buf);
291out_free:
292 kfree(strm.workspace);
293out:
294 return retval;
295}
296
297#endif /* CONFIG_BINFMT_ZFLAT */
298
299/****************************************************************************/
300
301static unsigned long
302calc_reloc(unsigned long r, struct lib_info *p, int curid, int internalp)
303{
304 unsigned long addr;
305 int id;
306 unsigned long start_brk;
307 unsigned long start_data;
308 unsigned long text_len;
309 unsigned long start_code;
310
311#ifdef CONFIG_BINFMT_SHARED_FLAT
312 if (r == 0)
313 id = curid; /* Relocs of 0 are always self referring */
314 else {
315 id = (r >> 24) & 0xff; /* Find ID for this reloc */
316 r &= 0x00ffffff; /* Trim ID off here */
317 }
318 if (id >= MAX_SHARED_LIBS) {
319 printk("BINFMT_FLAT: reference 0x%x to shared library %d",
320 (unsigned) r, id);
321 goto failed;
322 }
323 if (curid != id) {
324 if (internalp) {
325 printk("BINFMT_FLAT: reloc address 0x%x not in same module "
326 "(%d != %d)", (unsigned) r, curid, id);
327 goto failed;
328 } else if ( ! p->lib_list[id].loaded &&
329 load_flat_shared_library(id, p) > (unsigned long) -4096) {
330 printk("BINFMT_FLAT: failed to load library %d", id);
331 goto failed;
332 }
333 /* Check versioning information (i.e. time stamps) */
334 if (p->lib_list[id].build_date && p->lib_list[curid].build_date &&
335 p->lib_list[curid].build_date < p->lib_list[id].build_date) {
336 printk("BINFMT_FLAT: library %d is younger than %d", id, curid);
337 goto failed;
338 }
339 }
340#else
341 id = 0;
342#endif
343
344 start_brk = p->lib_list[id].start_brk;
345 start_data = p->lib_list[id].start_data;
346 start_code = p->lib_list[id].start_code;
347 text_len = p->lib_list[id].text_len;
348
349 if (!flat_reloc_valid(r, start_brk - start_data + text_len)) {
350 printk("BINFMT_FLAT: reloc outside program 0x%x (0 - 0x%x/0x%x)",
351 (int) r,(int)(start_brk-start_code),(int)text_len);
352 goto failed;
353 }
354
355 if (r < text_len) /* In text segment */
356 addr = r + start_code;
357 else /* In data segment */
358 addr = r - text_len + start_data;
359
360 /* Range checked already above so doing the range tests is redundant...*/
361 return(addr);
362
363failed:
364 printk(", killing %s!\n", current->comm);
365 send_sig(SIGSEGV, current, 0);
366
367 return RELOC_FAILED;
368}
369
370/****************************************************************************/
371
372void old_reloc(unsigned long rl)
373{
374#ifdef DEBUG
375 char *segment[] = { "TEXT", "DATA", "BSS", "*UNKNOWN*" };
376#endif
377 flat_v2_reloc_t r;
378 unsigned long *ptr;
379
380 r.value = rl;
381#if defined(CONFIG_COLDFIRE)
382 ptr = (unsigned long *) (current->mm->start_code + r.reloc.offset);
383#else
384 ptr = (unsigned long *) (current->mm->start_data + r.reloc.offset);
385#endif
386
387#ifdef DEBUG
388 printk("Relocation of variable at DATASEG+%x "
389 "(address %p, currently %x) into segment %s\n",
390 r.reloc.offset, ptr, (int)*ptr, segment[r.reloc.type]);
391#endif
392
393 switch (r.reloc.type) {
394 case OLD_FLAT_RELOC_TYPE_TEXT:
395 *ptr += current->mm->start_code;
396 break;
397 case OLD_FLAT_RELOC_TYPE_DATA:
398 *ptr += current->mm->start_data;
399 break;
400 case OLD_FLAT_RELOC_TYPE_BSS:
401 *ptr += current->mm->end_data;
402 break;
403 default:
404 printk("BINFMT_FLAT: Unknown relocation type=%x\n", r.reloc.type);
405 break;
406 }
407
408#ifdef DEBUG
409 printk("Relocation became %x\n", (int)*ptr);
410#endif
411}
412
413/****************************************************************************/
414
415static int load_flat_file(struct linux_binprm * bprm,
416 struct lib_info *libinfo, int id, unsigned long *extra_stack)
417{
418 struct flat_hdr * hdr;
419 unsigned long textpos = 0, datapos = 0, result;
420 unsigned long realdatastart = 0;
421 unsigned long text_len, data_len, bss_len, stack_len, flags;
72613e5f 422 unsigned long len, reallen, memp = 0;
1da177e4
LT		 423 unsigned long extra, rlim;
424 unsigned long *reloc = 0, *rp;
425 struct inode *inode;
426 int i, rev, relocs = 0;
427 loff_t fpos;
428 unsigned long start_code, end_code;
1ad3dcc0 429 int ret;
1da177e4
LT		 430
431 hdr = ((struct flat_hdr *) bprm->buf); /* exec-header */
0f7fc9e4 432 inode = bprm->file->f_path.dentry->d_inode;
1da177e4
LT		 433
434 text_len = ntohl(hdr->data_start);
435 data_len = ntohl(hdr->data_end) - ntohl(hdr->data_start);
436 bss_len = ntohl(hdr->bss_end) - ntohl(hdr->data_end);
437 stack_len = ntohl(hdr->stack_size);
438 if (extra_stack) {
439 stack_len += *extra_stack;
440 *extra_stack = stack_len;
441 }
442 relocs = ntohl(hdr->reloc_count);
443 flags = ntohl(hdr->flags);
444 rev = ntohl(hdr->rev);
445
845884d3 446 if (strncmp(hdr->magic, "bFLT", 4)) {
1da177e4
LT		 447 /*
448 * because a lot of people do not manage to produce good
449 * flat binaries, we leave this printk to help them realise
450 * the problem. We only print the error if its not a script file
451 */
452 if (strncmp(hdr->magic, "#!", 2))
845884d3 453 printk("BINFMT_FLAT: bad header magic\n");
1ad3dcc0
LY		 454 ret = -ENOEXEC;
455 goto err;
845884d3
GU		 456 }
457
458 if (flags & FLAT_FLAG_KTRACE)
459 printk("BINFMT_FLAT: Loading file: %s\n", bprm->filename);
460
461 if (rev != FLAT_VERSION && rev != OLD_FLAT_VERSION) {
462 printk("BINFMT_FLAT: bad flat file version 0x%x (supported 0x%x and 0x%x)\n", rev, FLAT_VERSION, OLD_FLAT_VERSION);
1ad3dcc0
LY		 463 ret = -ENOEXEC;
464 goto err;
1da177e4
LT		 465 }
466
467 /* Don't allow old format executables to use shared libraries */
468 if (rev == OLD_FLAT_VERSION && id != 0) {
469 printk("BINFMT_FLAT: shared libraries are not available before rev 0x%x\n",
470 (int) FLAT_VERSION);
1ad3dcc0
LY		 471 ret = -ENOEXEC;
472 goto err;
1da177e4
LT		 473 }
474
475 /*
476 * fix up the flags for the older format, there were all kinds
477 * of endian hacks, this only works for the simple cases
478 */
479 if (rev == OLD_FLAT_VERSION && flat_old_ram_flag(flags))
480 flags = FLAT_FLAG_RAM;
481
482#ifndef CONFIG_BINFMT_ZFLAT
483 if (flags & (FLAT_FLAG_GZIP|FLAT_FLAG_GZDATA)) {
484 printk("Support for ZFLAT executables is not enabled.\n");
1ad3dcc0
LY		 485 ret = -ENOEXEC;
486 goto err;
1da177e4
LT		 487 }
488#endif
489
490 /*
491 * Check initial limits. This avoids letting people circumvent
492 * size limits imposed on them by creating programs with large
493 * arrays in the data or bss.
494 */
495 rlim = current->signal->rlim[RLIMIT_DATA].rlim_cur;
496 if (rlim >= RLIM_INFINITY)
497 rlim = ~0;
1ad3dcc0
LY		 498 if (data_len + bss_len > rlim) {
499 ret = -ENOMEM;
500 goto err;
501 }
502
1da177e4
LT		 503 /* Flush all traces of the currently running executable */
504 if (id == 0) {
505 result = flush_old_exec(bprm);
1ad3dcc0
LY		 506 if (result) {
507 ret = result;
df88912a 508 goto err;
1ad3dcc0 509 }
1da177e4
LT		 510
511 /* OK, This is the point of no return */
fcc18e83 512 set_personality(PER_LINUX_32BIT);
1da177e4
LT		 513 }
514
515 /*
516 * calculate the extra space we need to map in
517 */
518 extra = max(bss_len + stack_len, relocs * sizeof(unsigned long));
519
520 /*
521 * there are a couple of cases here, the separate code/data
522 * case, and then the fully copied to RAM case which lumps
523 * it all together.
524 */
525 if ((flags & (FLAT_FLAG_RAM|FLAT_FLAG_GZIP)) == 0) {
526 /*
527 * this should give us a ROM ptr, but if it doesn't we don't
528 * really care
529 */
530 DBG_FLT("BINFMT_FLAT: ROM mapping of file (we hope)\n");
531
532 down_write(&current->mm->mmap_sem);
213b24c9 533 textpos = do_mmap(bprm->file, 0, text_len, PROT_READ|PROT_EXEC, MAP_PRIVATE, 0);
1da177e4
LT		 534 up_write(&current->mm->mmap_sem);
535 if (!textpos || textpos >= (unsigned long) -4096) {
536 if (!textpos)
537 textpos = (unsigned long) -ENOMEM;
538 printk("Unable to mmap process text, errno %d\n", (int)-textpos);
1ad3dcc0 539 ret = textpos;
df88912a 540 goto err;
1da177e4
LT		 541 }
542
72613e5f 543 len = data_len + extra + MAX_SHARED_LIBS * sizeof(unsigned long);
1da177e4 544 down_write(&current->mm->mmap_sem);
72613e5f
GU		 545 realdatastart = do_mmap(0, 0, len,
546 PROT_READ|PROT_WRITE|PROT_EXEC, MAP_PRIVATE, 0);
547 /* Remap to use all availabe slack region space */
548 if (realdatastart && (realdatastart < (unsigned long)-4096)) {
549 reallen = ksize(realdatastart);
550 if (reallen > len) {
551 realdatastart = do_mremap(realdatastart, len,
552 reallen, MREMAP_FIXED, realdatastart);
553 }
554 }
1da177e4
LT		 555 up_write(&current->mm->mmap_sem);
556
557 if (realdatastart == 0 || realdatastart >= (unsigned long)-4096) {
558 if (!realdatastart)
559 realdatastart = (unsigned long) -ENOMEM;
560 printk("Unable to allocate RAM for process data, errno %d\n",
c287ef1f 561 (int)-realdatastart);
1da177e4 562 do_munmap(current->mm, textpos, text_len);
1ad3dcc0 563 ret = realdatastart;
df88912a 564 goto err;
1da177e4
LT		 565 }
566 datapos = realdatastart + MAX_SHARED_LIBS * sizeof(unsigned long);
567
568 DBG_FLT("BINFMT_FLAT: Allocated data+bss+stack (%d bytes): %x\n",
569 (int)(data_len + bss_len + stack_len), (int)datapos);
570
571 fpos = ntohl(hdr->data_start);
572#ifdef CONFIG_BINFMT_ZFLAT
573 if (flags & FLAT_FLAG_GZDATA) {
574 result = decompress_exec(bprm, fpos, (char *) datapos,
575 data_len + (relocs * sizeof(unsigned long)), 0);
576 } else
577#endif
578 {
579 result = bprm->file->f_op->read(bprm->file, (char *) datapos,
580 data_len + (relocs * sizeof(unsigned long)), &fpos);
581 }
582 if (result >= (unsigned long)-4096) {
583 printk("Unable to read data+bss, errno %d\n", (int)-result);
584 do_munmap(current->mm, textpos, text_len);
585 do_munmap(current->mm, realdatastart, data_len + extra);
1ad3dcc0 586 ret = result;
df88912a 587 goto err;
1da177e4
LT		 588 }
589
590 reloc = (unsigned long *) (datapos+(ntohl(hdr->reloc_start)-text_len));
591 memp = realdatastart;
592
593 } else {
594
72613e5f 595 len = text_len + data_len + extra + MAX_SHARED_LIBS * sizeof(unsigned long);
1da177e4 596 down_write(&current->mm->mmap_sem);
72613e5f
GU		 597 textpos = do_mmap(0, 0, len,
598 PROT_READ | PROT_EXEC | PROT_WRITE, MAP_PRIVATE, 0);
599 /* Remap to use all availabe slack region space */
600 if (textpos && (textpos < (unsigned long) -4096)) {
601 reallen = ksize(textpos);
602 if (reallen > len) {
603 textpos = do_mremap(textpos, len, reallen,
604 MREMAP_FIXED, textpos);
605 }
606 }
1da177e4 607 up_write(&current->mm->mmap_sem);
72613e5f 608
1da177e4
LT		 609 if (!textpos || textpos >= (unsigned long) -4096) {
610 if (!textpos)
611 textpos = (unsigned long) -ENOMEM;
612 printk("Unable to allocate RAM for process text/data, errno %d\n",
613 (int)-textpos);
1ad3dcc0 614 ret = textpos;
df88912a 615 goto err;
1da177e4
LT		 616 }
617
618 realdatastart = textpos + ntohl(hdr->data_start);
619 datapos = realdatastart + MAX_SHARED_LIBS * sizeof(unsigned long);
620 reloc = (unsigned long *) (textpos + ntohl(hdr->reloc_start) +
621 MAX_SHARED_LIBS * sizeof(unsigned long));
622 memp = textpos;
623
624#ifdef CONFIG_BINFMT_ZFLAT
625 /*
626 * load it all in and treat it like a RAM load from now on
627 */
628 if (flags & FLAT_FLAG_GZIP) {
629 result = decompress_exec(bprm, sizeof (struct flat_hdr),
630 (((char *) textpos) + sizeof (struct flat_hdr)),
631 (text_len + data_len + (relocs * sizeof(unsigned long))
632 - sizeof (struct flat_hdr)),
633 0);
634 memmove((void *) datapos, (void *) realdatastart,
635 data_len + (relocs * sizeof(unsigned long)));
636 } else if (flags & FLAT_FLAG_GZDATA) {
637 fpos = 0;
638 result = bprm->file->f_op->read(bprm->file,
639 (char *) textpos, text_len, &fpos);
640 if (result < (unsigned long) -4096)
641 result = decompress_exec(bprm, text_len, (char *) datapos,
642 data_len + (relocs * sizeof(unsigned long)), 0);
643 }
644 else
645#endif
646 {
647 fpos = 0;
648 result = bprm->file->f_op->read(bprm->file,
649 (char *) textpos, text_len, &fpos);
650 if (result < (unsigned long) -4096) {
651 fpos = ntohl(hdr->data_start);
652 result = bprm->file->f_op->read(bprm->file, (char *) datapos,
653 data_len + (relocs * sizeof(unsigned long)), &fpos);
654 }
655 }
656 if (result >= (unsigned long)-4096) {
657 printk("Unable to read code+data+bss, errno %d\n",(int)-result);
658 do_munmap(current->mm, textpos, text_len + data_len + extra +
659 MAX_SHARED_LIBS * sizeof(unsigned long));
1ad3dcc0 660 ret = result;
df88912a 661 goto err;
1da177e4
LT		 662 }
663 }
664
665 if (flags & FLAT_FLAG_KTRACE)
666 printk("Mapping is %x, Entry point is %x, data_start is %x\n",
667 (int)textpos, 0x00ffffff&ntohl(hdr->entry), ntohl(hdr->data_start));
668
669 /* The main program needs a little extra setup in the task structure */
670 start_code = textpos + sizeof (struct flat_hdr);
671 end_code = textpos + text_len;
672 if (id == 0) {
673 current->mm->start_code = start_code;
674 current->mm->end_code = end_code;
675 current->mm->start_data = datapos;
676 current->mm->end_data = datapos + data_len;
677 /*
678 * set up the brk stuff, uses any slack left in data/bss/stack
679 * allocation. We put the brk after the bss (between the bss
680 * and stack) like other platforms.
681 */
682 current->mm->start_brk = datapos + data_len + bss_len;
683 current->mm->brk = (current->mm->start_brk + 3) & ~3;
684 current->mm->context.end_brk = memp + ksize((void *) memp) - stack_len;
1da177e4
LT		 685 }
686
687 if (flags & FLAT_FLAG_KTRACE)
688 printk("%s %s: TEXT=%x-%x DATA=%x-%x BSS=%x-%x\n",
689 id ? "Lib" : "Load", bprm->filename,
690 (int) start_code, (int) end_code,
691 (int) datapos,
692 (int) (datapos + data_len),
693 (int) (datapos + data_len),
694 (int) (((datapos + data_len + bss_len) + 3) & ~3));
695
696 text_len -= sizeof(struct flat_hdr); /* the real code len */
697
698 /* Store the current module values into the global library structure */
699 libinfo->lib_list[id].start_code = start_code;
700 libinfo->lib_list[id].start_data = datapos;
701 libinfo->lib_list[id].start_brk = datapos + data_len + bss_len;
702 libinfo->lib_list[id].text_len = text_len;
703 libinfo->lib_list[id].loaded = 1;
704 libinfo->lib_list[id].entry = (0x00ffffff & ntohl(hdr->entry)) + textpos;
705 libinfo->lib_list[id].build_date = ntohl(hdr->build_date);
706
707 /*
708 * We just load the allocations into some temporary memory to
709 * help simplify all this mumbo jumbo
710 *
711 * We've got two different sections of relocation entries.
712 * The first is the GOT which resides at the begining of the data segment
713 * and is terminated with a -1. This one can be relocated in place.
714 * The second is the extra relocation entries tacked after the image's
715 * data segment. These require a little more processing as the entry is
716 * really an offset into the image which contains an offset into the
717 * image.
718 */
719 if (flags & FLAT_FLAG_GOTPIC) {
720 for (rp = (unsigned long *)datapos; *rp != 0xffffffff; rp++) {
721 unsigned long addr;
722 if (*rp) {
723 addr = calc_reloc(*rp, libinfo, id, 0);
1ad3dcc0
LY		 724 if (addr == RELOC_FAILED) {
725 ret = -ENOEXEC;
df88912a 726 goto err;
1ad3dcc0 727 }
1da177e4
LT		 728 *rp = addr;
729 }
730 }
731 }
732
733 /*
734 * Now run through the relocation entries.
735 * We've got to be careful here as C++ produces relocatable zero
736 * entries in the constructor and destructor tables which are then
737 * tested for being not zero (which will always occur unless we're
738 * based from address zero). This causes an endless loop as __start
739 * is at zero. The solution used is to not relocate zero addresses.
740 * This has the negative side effect of not allowing a global data
741 * reference to be statically initialised to _stext (I've moved
742 * __start to address 4 so that is okay).
743 */
744 if (rev > OLD_FLAT_VERSION) {
745 for (i=0; i < relocs; i++) {
746 unsigned long addr, relval;
747
748 /* Get the address of the pointer to be
749 relocated (of course, the address has to be
750 relocated first). */
751 relval = ntohl(reloc[i]);
752 addr = flat_get_relocate_addr(relval);
753 rp = (unsigned long *) calc_reloc(addr, libinfo, id, 1);
1ad3dcc0
LY		 754 if (rp == (unsigned long *)RELOC_FAILED) {
755 ret = -ENOEXEC;
df88912a 756 goto err;
1ad3dcc0 757 }
1da177e4
LT		 758
759 /* Get the pointer's value. */
760 addr = flat_get_addr_from_rp(rp, relval, flags);
761 if (addr != 0) {
762 /*
763 * Do the relocation. PIC relocs in the data section are
764 * already in target order
765 */
766 if ((flags & FLAT_FLAG_GOTPIC) == 0)
767 addr = ntohl(addr);
768 addr = calc_reloc(addr, libinfo, id, 0);
1ad3dcc0
LY		 769 if (addr == RELOC_FAILED) {
770 ret = -ENOEXEC;
df88912a 771 goto err;
1ad3dcc0 772 }
1da177e4
LT		 773
774 /* Write back the relocated pointer. */
775 flat_put_addr_at_rp(rp, addr, relval);
776 }
777 }
778 } else {
779 for (i=0; i < relocs; i++)
780 old_reloc(ntohl(reloc[i]));
781 }
782
783 flush_icache_range(start_code, end_code);
784
785 /* zero the BSS, BRK and stack areas */
786 memset((void*)(datapos + data_len), 0, bss_len +
787 (memp + ksize((void *) memp) - stack_len - /* end brk */
788 libinfo->lib_list[id].start_brk) + /* start brk */
789 stack_len);
790
791 return 0;
1ad3dcc0
LY		 792err:
793 return ret;
1da177e4
LT		 794}
795
796
797/****************************************************************************/
798#ifdef CONFIG_BINFMT_SHARED_FLAT
799
800/*
801 * Load a shared library into memory. The library gets its own data
802 * segment (including bss) but not argv/argc/environ.
803 */
804
805static int load_flat_shared_library(int id, struct lib_info *libs)
806{
807 struct linux_binprm bprm;
808 int res;
809 char buf[16];
810
811 /* Create the file name */
812 sprintf(buf, "/lib/lib%d.so", id);
813
814 /* Open the file up */
815 bprm.filename = buf;
816 bprm.file = open_exec(bprm.filename);
817 res = PTR_ERR(bprm.file);
818 if (IS_ERR(bprm.file))
819 return res;
820
821 res = prepare_binprm(&bprm);
822
823 if (res <= (unsigned long)-4096)
824 res = load_flat_file(&bprm, libs, id, NULL);
825 if (bprm.file) {
826 allow_write_access(bprm.file);
827 fput(bprm.file);
828 bprm.file = NULL;
829 }
830 return(res);
831}
832
833#endif /* CONFIG_BINFMT_SHARED_FLAT */
834/****************************************************************************/
835
836/*
837 * These are the functions used to load flat style executables and shared
838 * libraries. There is no binary dependent code anywhere else.
839 */
840
841static int load_flat_binary(struct linux_binprm * bprm, struct pt_regs * regs)
842{
843 struct lib_info libinfo;
844 unsigned long p = bprm->p;
845 unsigned long stack_len;
846 unsigned long start_addr;
847 unsigned long *sp;
848 int res;
849 int i, j;
850
851 memset(&libinfo, 0, sizeof(libinfo));
852 /*
853 * We have to add the size of our arguments to our stack size
854 * otherwise it's too easy for users to create stack overflows
855 * by passing in a huge argument list. And yes, we have to be
856 * pedantic and include space for the argv/envp array as it may have
857 * a lot of entries.
858 */
859#define TOP_OF_ARGS (PAGE_SIZE * MAX_ARG_PAGES - sizeof(void *))
860 stack_len = TOP_OF_ARGS - bprm->p; /* the strings */
861 stack_len += (bprm->argc + 1) * sizeof(char *); /* the argv array */
862 stack_len += (bprm->envc + 1) * sizeof(char *); /* the envp array */
863
864
865 res = load_flat_file(bprm, &libinfo, 0, &stack_len);
866 if (res > (unsigned long)-4096)
867 return res;
868
869 /* Update data segment pointers for all libraries */
870 for (i=0; i<MAX_SHARED_LIBS; i++)
871 if (libinfo.lib_list[i].loaded)
872 for (j=0; j<MAX_SHARED_LIBS; j++)
873 (-(j+1))[(unsigned long *)(libinfo.lib_list[i].start_data)] =
874 (libinfo.lib_list[j].loaded)?
875 libinfo.lib_list[j].start_data:UNLOADED_LIB;
876
877 compute_creds(bprm);
878 current->flags &= ~PF_FORKNOEXEC;
879
880 set_binfmt(&flat_format);
881
882 p = ((current->mm->context.end_brk + stack_len + 3) & ~3) - 4;
883 DBG_FLT("p=%x\n", (int)p);
884
885 /* copy the arg pages onto the stack, this could be more efficient :-) */
886 for (i = TOP_OF_ARGS - 1; i >= bprm->p; i--)
887 * (char *) --p =
888 ((char *) page_address(bprm->page[i/PAGE_SIZE]))[i % PAGE_SIZE];
889
890 sp = (unsigned long *) create_flat_tables(p, bprm);
891
892 /* Fake some return addresses to ensure the call chain will
893 * initialise library in order for us. We are required to call
894 * lib 1 first, then 2, ... and finally the main program (id 0).
895 */
896 start_addr = libinfo.lib_list[0].entry;
897
898#ifdef CONFIG_BINFMT_SHARED_FLAT
899 for (i = MAX_SHARED_LIBS-1; i>0; i--) {
900 if (libinfo.lib_list[i].loaded) {
901 /* Push previos first to call address */
902 --sp; put_user(start_addr, sp);
903 start_addr = libinfo.lib_list[i].entry;
904 }
905 }
906#endif
907
908 /* Stash our initial stack pointer into the mm structure */
909 current->mm->start_stack = (unsigned long )sp;
910
911
912 DBG_FLT("start_thread(regs=0x%x, entry=0x%x, start_stack=0x%x)\n",
913 (int)regs, (int)start_addr, (int)current->mm->start_stack);
914
915 start_thread(regs, start_addr, current->mm->start_stack);
916
917 if (current->ptrace & PT_PTRACED)
918 send_sig(SIGTRAP, current, 0);
919
920 return 0;
921}
922
923/****************************************************************************/
924
925static int __init init_flat_binfmt(void)
926{
927 return register_binfmt(&flat_format);
928}
929
930static void __exit exit_flat_binfmt(void)
931{
932 unregister_binfmt(&flat_format);
933}
934
935/****************************************************************************/
936
937core_initcall(init_flat_binfmt);
938module_exit(exit_flat_binfmt);
939
940/****************************************************************************/
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