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>
19 #include <linux/kernel.h>
20 #include <linux/sched.h>
21 #include <linux/mm.h>
22 #include <linux/mman.h>
23 #include <linux/errno.h>
24 #include <linux/signal.h>
25 #include <linux/string.h>
26 #include <linux/fs.h>
27 #include <linux/file.h>
28 #include <linux/stat.h>
29 #include <linux/fcntl.h>
30 #include <linux/ptrace.h>
31 #include <linux/user.h>
32 #include <linux/slab.h>
33 #include <linux/binfmts.h>
34 #include <linux/personality.h>
35 #include <linux/init.h>
36 #include <linux/flat.h>
37 #include <linux/syscalls.h>
38
39 #include <asm/byteorder.h>
40 #include <asm/system.h>
41 #include <asm/uaccess.h>
42 #include <asm/unaligned.h>
43 #include <asm/cacheflush.h>
44 #include <asm/page.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 /*
59 * User data (stack, data section and bss) needs to be aligned
60 * for the same reasons as SLAB memory is, and to the same amount.
61 * Avoid duplicating architecture specific code by using the same
62 * macro as with SLAB allocation:
63 */
64 #ifdef ARCH_SLAB_MINALIGN
65 #define FLAT_DATA_ALIGN (ARCH_SLAB_MINALIGN)
66 #else
67 #define FLAT_DATA_ALIGN (sizeof(void *))
68 #endif
69
70 #define RELOC_FAILED 0xff00ff01 /* Relocation incorrect somewhere */
71 #define UNLOADED_LIB 0x7ff000ff /* Placeholder for unused library */
72
73 struct lib_info {
74 struct {
75 unsigned long start_code; /* Start of text segment */
76 unsigned long start_data; /* Start of data segment */
77 unsigned long start_brk; /* End of data segment */
78 unsigned long text_len; /* Length of text segment */
79 unsigned long entry; /* Start address for this module */
80 unsigned long build_date; /* When this one was compiled */
81 short loaded; /* Has this library been loaded? */
82 } lib_list[MAX_SHARED_LIBS];
83 };
84
85 #ifdef CONFIG_BINFMT_SHARED_FLAT
86 static int load_flat_shared_library(int id, struct lib_info *p);
87 #endif
88
89 static int load_flat_binary(struct linux_binprm *, struct pt_regs * regs);
90 static int flat_core_dump(long signr, struct pt_regs *regs, struct file *file, unsigned long limit);
91
92 static struct linux_binfmt flat_format = {
93 .module = THIS_MODULE,
94 .load_binary = load_flat_binary,
95 .core_dump = flat_core_dump,
96 .min_coredump = PAGE_SIZE
97 };
98
99 /****************************************************************************/
100 /*
101 * Routine writes a core dump image in the current directory.
102 * Currently only a stub-function.
103 */
104
105 static int flat_core_dump(long signr, struct pt_regs *regs, struct file *file, unsigned long limit)
106 {
107 printk("Process %s:%d received signr %d and should have core dumped\n",
108 current->comm, current->pid, (int) signr);
109 return(1);
110 }
111
112 /****************************************************************************/
113 /*
114 * create_flat_tables() parses the env- and arg-strings in new user
115 * memory and creates the pointer tables from them, and puts their
116 * addresses on the "stack", returning the new stack pointer value.
117 */
118
119 static unsigned long create_flat_tables(
120 unsigned long pp,
121 struct linux_binprm * bprm)
122 {
123 unsigned long *argv,*envp;
124 unsigned long * sp;
125 char * p = (char*)pp;
126 int argc = bprm->argc;
127 int envc = bprm->envc;
128 char uninitialized_var(dummy);
129
130 sp = (unsigned long *)p;
131 sp -= (envc + argc + 2) + 1 + (flat_argvp_envp_on_stack() ? 2 : 0);
132 sp = (unsigned long *) ((unsigned long)sp & -FLAT_DATA_ALIGN);
133 argv = sp + 1 + (flat_argvp_envp_on_stack() ? 2 : 0);
134 envp = argv + (argc + 1);
135
136 if (flat_argvp_envp_on_stack()) {
137 put_user((unsigned long) envp, sp + 2);
138 put_user((unsigned long) argv, sp + 1);
139 }
140
141 put_user(argc, sp);
142 current->mm->arg_start = (unsigned long) p;
143 while (argc-->0) {
144 put_user((unsigned long) p, argv++);
145 do {
146 get_user(dummy, p); p++;
147 } while (dummy);
148 }
149 put_user((unsigned long) NULL, argv);
150 current->mm->arg_end = current->mm->env_start = (unsigned long) p;
151 while (envc-->0) {
152 put_user((unsigned long)p, envp); envp++;
153 do {
154 get_user(dummy, p); p++;
155 } while (dummy);
156 }
157 put_user((unsigned long) NULL, envp);
158 current->mm->env_end = (unsigned long) p;
159 return (unsigned long)sp;
160 }
161
162 /****************************************************************************/
163
164 #ifdef CONFIG_BINFMT_ZFLAT
165
166 #include <linux/zlib.h>
167
168 #define LBUFSIZE 4000
169
170 /* gzip flag byte */
171 #define ASCII_FLAG 0x01 /* bit 0 set: file probably ASCII text */
172 #define CONTINUATION 0x02 /* bit 1 set: continuation of multi-part gzip file */
173 #define EXTRA_FIELD 0x04 /* bit 2 set: extra field present */
174 #define ORIG_NAME 0x08 /* bit 3 set: original file name present */
175 #define COMMENT 0x10 /* bit 4 set: file comment present */
176 #define ENCRYPTED 0x20 /* bit 5 set: file is encrypted */
177 #define RESERVED 0xC0 /* bit 6,7: reserved */
178
179 static int decompress_exec(
180 struct linux_binprm *bprm,
181 unsigned long offset,
182 char *dst,
183 long len,
184 int fd)
185 {
186 unsigned char *buf;
187 z_stream strm;
188 loff_t fpos;
189 int ret, retval;
190
191 DBG_FLT("decompress_exec(offset=%x,buf=%x,len=%x)\n",(int)offset, (int)dst, (int)len);
192
193 memset(&strm, 0, sizeof(strm));
194 strm.workspace = kmalloc(zlib_inflate_workspacesize(), GFP_KERNEL);
195 if (strm.workspace == NULL) {
196 DBG_FLT("binfmt_flat: no memory for decompress workspace\n");
197 return -ENOMEM;
198 }
199 buf = kmalloc(LBUFSIZE, GFP_KERNEL);
200 if (buf == NULL) {
201 DBG_FLT("binfmt_flat: no memory for read buffer\n");
202 retval = -ENOMEM;
203 goto out_free;
204 }
205
206 /* Read in first chunk of data and parse gzip header. */
207 fpos = offset;
208 ret = bprm->file->f_op->read(bprm->file, buf, LBUFSIZE, &fpos);
209
210 strm.next_in = buf;
211 strm.avail_in = ret;
212 strm.total_in = 0;
213
214 retval = -ENOEXEC;
215
216 /* Check minimum size -- gzip header */
217 if (ret < 10) {
218 DBG_FLT("binfmt_flat: file too small?\n");
219 goto out_free_buf;
220 }
221
222 /* Check gzip magic number */
223 if ((buf[0] != 037) || ((buf[1] != 0213) && (buf[1] != 0236))) {
224 DBG_FLT("binfmt_flat: unknown compression magic?\n");
225 goto out_free_buf;
226 }
227
228 /* Check gzip method */
229 if (buf[2] != 8) {
230 DBG_FLT("binfmt_flat: unknown compression method?\n");
231 goto out_free_buf;
232 }
233 /* Check gzip flags */
234 if ((buf[3] & ENCRYPTED) || (buf[3] & CONTINUATION) ||
235 (buf[3] & RESERVED)) {
236 DBG_FLT("binfmt_flat: unknown flags?\n");
237 goto out_free_buf;
238 }
239
240 ret = 10;
241 if (buf[3] & EXTRA_FIELD) {
242 ret += 2 + buf[10] + (buf[11] << 8);
243 if (unlikely(LBUFSIZE <= ret)) {
244 DBG_FLT("binfmt_flat: buffer overflow (EXTRA)?\n");
245 goto out_free_buf;
246 }
247 }
248 if (buf[3] & ORIG_NAME) {
249 while (ret < LBUFSIZE && buf[ret++] != 0)
250 ;
251 if (unlikely(LBUFSIZE == ret)) {
252 DBG_FLT("binfmt_flat: buffer overflow (ORIG_NAME)?\n");
253 goto out_free_buf;
254 }
255 }
256 if (buf[3] & COMMENT) {
257 while (ret < LBUFSIZE && buf[ret++] != 0)
258 ;
259 if (unlikely(LBUFSIZE == ret)) {
260 DBG_FLT("binfmt_flat: buffer overflow (COMMENT)?\n");
261 goto out_free_buf;
262 }
263 }
264
265 strm.next_in += ret;
266 strm.avail_in -= ret;
267
268 strm.next_out = dst;
269 strm.avail_out = len;
270 strm.total_out = 0;
271
272 if (zlib_inflateInit2(&strm, -MAX_WBITS) != Z_OK) {
273 DBG_FLT("binfmt_flat: zlib init failed?\n");
274 goto out_free_buf;
275 }
276
277 while ((ret = zlib_inflate(&strm, Z_NO_FLUSH)) == Z_OK) {
278 ret = bprm->file->f_op->read(bprm->file, buf, LBUFSIZE, &fpos);
279 if (ret <= 0)
280 break;
281 if (ret >= (unsigned long) -4096)
282 break;
283 len -= ret;
284
285 strm.next_in = buf;
286 strm.avail_in = ret;
287 strm.total_in = 0;
288 }
289
290 if (ret < 0) {
291 DBG_FLT("binfmt_flat: decompression failed (%d), %s\n",
292 ret, strm.msg);
293 goto out_zlib;
294 }
295
296 retval = 0;
297 out_zlib:
298 zlib_inflateEnd(&strm);
299 out_free_buf:
300 kfree(buf);
301 out_free:
302 kfree(strm.workspace);
303 return retval;
304 }
305
306 #endif /* CONFIG_BINFMT_ZFLAT */
307
308 /****************************************************************************/
309
310 static unsigned long
311 calc_reloc(unsigned long r, struct lib_info *p, int curid, int internalp)
312 {
313 unsigned long addr;
314 int id;
315 unsigned long start_brk;
316 unsigned long start_data;
317 unsigned long text_len;
318 unsigned long start_code;
319
320 #ifdef CONFIG_BINFMT_SHARED_FLAT
321 if (r == 0)
322 id = curid; /* Relocs of 0 are always self referring */
323 else {
324 id = (r >> 24) & 0xff; /* Find ID for this reloc */
325 r &= 0x00ffffff; /* Trim ID off here */
326 }
327 if (id >= MAX_SHARED_LIBS) {
328 printk("BINFMT_FLAT: reference 0x%x to shared library %d",
329 (unsigned) r, id);
330 goto failed;
331 }
332 if (curid != id) {
333 if (internalp) {
334 printk("BINFMT_FLAT: reloc address 0x%x not in same module "
335 "(%d != %d)", (unsigned) r, curid, id);
336 goto failed;
337 } else if ( ! p->lib_list[id].loaded &&
338 load_flat_shared_library(id, p) > (unsigned long) -4096) {
339 printk("BINFMT_FLAT: failed to load library %d", id);
340 goto failed;
341 }
342 /* Check versioning information (i.e. time stamps) */
343 if (p->lib_list[id].build_date && p->lib_list[curid].build_date &&
344 p->lib_list[curid].build_date < p->lib_list[id].build_date) {
345 printk("BINFMT_FLAT: library %d is younger than %d", id, curid);
346 goto failed;
347 }
348 }
349 #else
350 id = 0;
351 #endif
352
353 start_brk = p->lib_list[id].start_brk;
354 start_data = p->lib_list[id].start_data;
355 start_code = p->lib_list[id].start_code;
356 text_len = p->lib_list[id].text_len;
357
358 if (!flat_reloc_valid(r, start_brk - start_data + text_len)) {
359 printk("BINFMT_FLAT: reloc outside program 0x%x (0 - 0x%x/0x%x)",
360 (int) r,(int)(start_brk-start_code),(int)text_len);
361 goto failed;
362 }
363
364 if (r < text_len) /* In text segment */
365 addr = r + start_code;
366 else /* In data segment */
367 addr = r - text_len + start_data;
368
369 /* Range checked already above so doing the range tests is redundant...*/
370 return(addr);
371
372 failed:
373 printk(", killing %s!\n", current->comm);
374 send_sig(SIGSEGV, current, 0);
375
376 return RELOC_FAILED;
377 }
378
379 /****************************************************************************/
380
381 void old_reloc(unsigned long rl)
382 {
383 #ifdef DEBUG
384 char *segment[] = { "TEXT", "DATA", "BSS", "*UNKNOWN*" };
385 #endif
386 flat_v2_reloc_t r;
387 unsigned long *ptr;
388
389 r.value = rl;
390 #if defined(CONFIG_COLDFIRE)
391 ptr = (unsigned long *) (current->mm->start_code + r.reloc.offset);
392 #else
393 ptr = (unsigned long *) (current->mm->start_data + r.reloc.offset);
394 #endif
395
396 #ifdef DEBUG
397 printk("Relocation of variable at DATASEG+%x "
398 "(address %p, currently %x) into segment %s\n",
399 r.reloc.offset, ptr, (int)*ptr, segment[r.reloc.type]);
400 #endif
401
402 switch (r.reloc.type) {
403 case OLD_FLAT_RELOC_TYPE_TEXT:
404 *ptr += current->mm->start_code;
405 break;
406 case OLD_FLAT_RELOC_TYPE_DATA:
407 *ptr += current->mm->start_data;
408 break;
409 case OLD_FLAT_RELOC_TYPE_BSS:
410 *ptr += current->mm->end_data;
411 break;
412 default:
413 printk("BINFMT_FLAT: Unknown relocation type=%x\n", r.reloc.type);
414 break;
415 }
416
417 #ifdef DEBUG
418 printk("Relocation became %x\n", (int)*ptr);
419 #endif
420 }
421
422 /****************************************************************************/
423
424 static int load_flat_file(struct linux_binprm * bprm,
425 struct lib_info *libinfo, int id, unsigned long *extra_stack)
426 {
427 struct flat_hdr * hdr;
428 unsigned long textpos = 0, datapos = 0, result;
429 unsigned long realdatastart = 0;
430 unsigned long text_len, data_len, bss_len, stack_len, flags;
431 unsigned long len, memp = 0;
432 unsigned long memp_size, extra, rlim;
433 unsigned long *reloc = 0, *rp;
434 struct inode *inode;
435 int i, rev, relocs = 0;
436 loff_t fpos;
437 unsigned long start_code, end_code;
438 int ret;
439
440 hdr = ((struct flat_hdr *) bprm->buf); /* exec-header */
441 inode = bprm->file->f_path.dentry->d_inode;
442
443 text_len = ntohl(hdr->data_start);
444 data_len = ntohl(hdr->data_end) - ntohl(hdr->data_start);
445 bss_len = ntohl(hdr->bss_end) - ntohl(hdr->data_end);
446 stack_len = ntohl(hdr->stack_size);
447 if (extra_stack) {
448 stack_len += *extra_stack;
449 *extra_stack = stack_len;
450 }
451 relocs = ntohl(hdr->reloc_count);
452 flags = ntohl(hdr->flags);
453 rev = ntohl(hdr->rev);
454
455 if (strncmp(hdr->magic, "bFLT", 4)) {
456 /*
457 * Previously, here was a printk to tell people
458 * "BINFMT_FLAT: bad header magic".
459 * But for the kernel which also use ELF FD-PIC format, this
460 * error message is confusing.
461 * because a lot of people do not manage to produce good
462 */
463 ret = -ENOEXEC;
464 goto err;
465 }
466
467 if (flags & FLAT_FLAG_KTRACE)
468 printk("BINFMT_FLAT: Loading file: %s\n", bprm->filename);
469
470 if (rev != FLAT_VERSION && rev != OLD_FLAT_VERSION) {
471 printk("BINFMT_FLAT: bad flat file version 0x%x (supported "
472 "0x%lx and 0x%lx)\n",
473 rev, FLAT_VERSION, OLD_FLAT_VERSION);
474 ret = -ENOEXEC;
475 goto err;
476 }
477
478 /* Don't allow old format executables to use shared libraries */
479 if (rev == OLD_FLAT_VERSION && id != 0) {
480 printk("BINFMT_FLAT: shared libraries are not available before rev 0x%x\n",
481 (int) FLAT_VERSION);
482 ret = -ENOEXEC;
483 goto err;
484 }
485
486 /*
487 * fix up the flags for the older format, there were all kinds
488 * of endian hacks, this only works for the simple cases
489 */
490 if (rev == OLD_FLAT_VERSION && flat_old_ram_flag(flags))
491 flags = FLAT_FLAG_RAM;
492
493 #ifndef CONFIG_BINFMT_ZFLAT
494 if (flags & (FLAT_FLAG_GZIP|FLAT_FLAG_GZDATA)) {
495 printk("Support for ZFLAT executables is not enabled.\n");
496 ret = -ENOEXEC;
497 goto err;
498 }
499 #endif
500
501 /*
502 * Check initial limits. This avoids letting people circumvent
503 * size limits imposed on them by creating programs with large
504 * arrays in the data or bss.
505 */
506 rlim = current->signal->rlim[RLIMIT_DATA].rlim_cur;
507 if (rlim >= RLIM_INFINITY)
508 rlim = ~0;
509 if (data_len + bss_len > rlim) {
510 ret = -ENOMEM;
511 goto err;
512 }
513
514 /* Flush all traces of the currently running executable */
515 if (id == 0) {
516 result = flush_old_exec(bprm);
517 if (result) {
518 ret = result;
519 goto err;
520 }
521
522 /* OK, This is the point of no return */
523 set_personality(PER_LINUX_32BIT);
524 setup_new_exec(bprm);
525 }
526
527 /*
528 * calculate the extra space we need to map in
529 */
530 extra = max_t(unsigned long, bss_len + stack_len,
531 relocs * sizeof(unsigned long));
532
533 /*
534 * there are a couple of cases here, the separate code/data
535 * case, and then the fully copied to RAM case which lumps
536 * it all together.
537 */
538 if ((flags & (FLAT_FLAG_RAM|FLAT_FLAG_GZIP)) == 0) {
539 /*
540 * this should give us a ROM ptr, but if it doesn't we don't
541 * really care
542 */
543 DBG_FLT("BINFMT_FLAT: ROM mapping of file (we hope)\n");
544
545 down_write(¤t->mm->mmap_sem);
546 textpos = do_mmap(bprm->file, 0, text_len, PROT_READ|PROT_EXEC,
547 MAP_PRIVATE|MAP_EXECUTABLE, 0);
548 up_write(¤t->mm->mmap_sem);
549 if (!textpos || textpos >= (unsigned long) -4096) {
550 if (!textpos)
551 textpos = (unsigned long) -ENOMEM;
552 printk("Unable to mmap process text, errno %d\n", (int)-textpos);
553 ret = textpos;
554 goto err;
555 }
556
557 len = data_len + extra + MAX_SHARED_LIBS * sizeof(unsigned long);
558 len = PAGE_ALIGN(len);
559 down_write(¤t->mm->mmap_sem);
560 realdatastart = do_mmap(0, 0, len,
561 PROT_READ|PROT_WRITE|PROT_EXEC, MAP_PRIVATE, 0);
562 up_write(¤t->mm->mmap_sem);
563
564 if (realdatastart == 0 || realdatastart >= (unsigned long)-4096) {
565 if (!realdatastart)
566 realdatastart = (unsigned long) -ENOMEM;
567 printk("Unable to allocate RAM for process data, errno %d\n",
568 (int)-realdatastart);
569 do_munmap(current->mm, textpos, text_len);
570 ret = realdatastart;
571 goto err;
572 }
573 datapos = ALIGN(realdatastart +
574 MAX_SHARED_LIBS * sizeof(unsigned long),
575 FLAT_DATA_ALIGN);
576
577 DBG_FLT("BINFMT_FLAT: Allocated data+bss+stack (%d bytes): %x\n",
578 (int)(data_len + bss_len + stack_len), (int)datapos);
579
580 fpos = ntohl(hdr->data_start);
581 #ifdef CONFIG_BINFMT_ZFLAT
582 if (flags & FLAT_FLAG_GZDATA) {
583 result = decompress_exec(bprm, fpos, (char *) datapos,
584 data_len + (relocs * sizeof(unsigned long)), 0);
585 } else
586 #endif
587 {
588 result = bprm->file->f_op->read(bprm->file, (char *) datapos,
589 data_len + (relocs * sizeof(unsigned long)), &fpos);
590 }
591 if (result >= (unsigned long)-4096) {
592 printk("Unable to read data+bss, errno %d\n", (int)-result);
593 do_munmap(current->mm, textpos, text_len);
594 do_munmap(current->mm, realdatastart, data_len + extra);
595 ret = result;
596 goto err;
597 }
598
599 reloc = (unsigned long *) (datapos+(ntohl(hdr->reloc_start)-text_len));
600 memp = realdatastart;
601 memp_size = len;
602 } else {
603
604 len = text_len + data_len + extra + MAX_SHARED_LIBS * sizeof(unsigned long);
605 len = PAGE_ALIGN(len);
606 down_write(¤t->mm->mmap_sem);
607 textpos = do_mmap(0, 0, len,
608 PROT_READ | PROT_EXEC | PROT_WRITE, MAP_PRIVATE, 0);
609 up_write(¤t->mm->mmap_sem);
610
611 if (!textpos || textpos >= (unsigned long) -4096) {
612 if (!textpos)
613 textpos = (unsigned long) -ENOMEM;
614 printk("Unable to allocate RAM for process text/data, errno %d\n",
615 (int)-textpos);
616 ret = textpos;
617 goto err;
618 }
619
620 realdatastart = textpos + ntohl(hdr->data_start);
621 datapos = ALIGN(realdatastart +
622 MAX_SHARED_LIBS * sizeof(unsigned long),
623 FLAT_DATA_ALIGN);
624
625 reloc = (unsigned long *)
626 (datapos + (ntohl(hdr->reloc_start) - text_len));
627 memp = textpos;
628 memp_size = len;
629 #ifdef CONFIG_BINFMT_ZFLAT
630 /*
631 * load it all in and treat it like a RAM load from now on
632 */
633 if (flags & FLAT_FLAG_GZIP) {
634 result = decompress_exec(bprm, sizeof (struct flat_hdr),
635 (((char *) textpos) + sizeof (struct flat_hdr)),
636 (text_len + data_len + (relocs * sizeof(unsigned long))
637 - sizeof (struct flat_hdr)),
638 0);
639 memmove((void *) datapos, (void *) realdatastart,
640 data_len + (relocs * sizeof(unsigned long)));
641 } else if (flags & FLAT_FLAG_GZDATA) {
642 fpos = 0;
643 result = bprm->file->f_op->read(bprm->file,
644 (char *) textpos, text_len, &fpos);
645 if (result < (unsigned long) -4096)
646 result = decompress_exec(bprm, text_len, (char *) datapos,
647 data_len + (relocs * sizeof(unsigned long)), 0);
648 }
649 else
650 #endif
651 {
652 fpos = 0;
653 result = bprm->file->f_op->read(bprm->file,
654 (char *) textpos, text_len, &fpos);
655 if (result < (unsigned long) -4096) {
656 fpos = ntohl(hdr->data_start);
657 result = bprm->file->f_op->read(bprm->file, (char *) datapos,
658 data_len + (relocs * sizeof(unsigned long)), &fpos);
659 }
660 }
661 if (result >= (unsigned long)-4096) {
662 printk("Unable to read code+data+bss, errno %d\n",(int)-result);
663 do_munmap(current->mm, textpos, text_len + data_len + extra +
664 MAX_SHARED_LIBS * sizeof(unsigned long));
665 ret = result;
666 goto err;
667 }
668 }
669
670 if (flags & FLAT_FLAG_KTRACE)
671 printk("Mapping is %x, Entry point is %x, data_start is %x\n",
672 (int)textpos, 0x00ffffff&ntohl(hdr->entry), ntohl(hdr->data_start));
673
674 /* The main program needs a little extra setup in the task structure */
675 start_code = textpos + sizeof (struct flat_hdr);
676 end_code = textpos + text_len;
677 if (id == 0) {
678 current->mm->start_code = start_code;
679 current->mm->end_code = end_code;
680 current->mm->start_data = datapos;
681 current->mm->end_data = datapos + data_len;
682 /*
683 * set up the brk stuff, uses any slack left in data/bss/stack
684 * allocation. We put the brk after the bss (between the bss
685 * and stack) like other platforms.
686 * Userspace code relies on the stack pointer starting out at
687 * an address right at the end of a page.
688 */
689 current->mm->start_brk = datapos + data_len + bss_len;
690 current->mm->brk = (current->mm->start_brk + 3) & ~3;
691 current->mm->context.end_brk = memp + memp_size - stack_len;
692 }
693
694 if (flags & FLAT_FLAG_KTRACE)
695 printk("%s %s: TEXT=%x-%x DATA=%x-%x BSS=%x-%x\n",
696 id ? "Lib" : "Load", bprm->filename,
697 (int) start_code, (int) end_code,
698 (int) datapos,
699 (int) (datapos + data_len),
700 (int) (datapos + data_len),
701 (int) (((datapos + data_len + bss_len) + 3) & ~3));
702
703 text_len -= sizeof(struct flat_hdr); /* the real code len */
704
705 /* Store the current module values into the global library structure */
706 libinfo->lib_list[id].start_code = start_code;
707 libinfo->lib_list[id].start_data = datapos;
708 libinfo->lib_list[id].start_brk = datapos + data_len + bss_len;
709 libinfo->lib_list[id].text_len = text_len;
710 libinfo->lib_list[id].loaded = 1;
711 libinfo->lib_list[id].entry = (0x00ffffff & ntohl(hdr->entry)) + textpos;
712 libinfo->lib_list[id].build_date = ntohl(hdr->build_date);
713
714 /*
715 * We just load the allocations into some temporary memory to
716 * help simplify all this mumbo jumbo
717 *
718 * We've got two different sections of relocation entries.
719 * The first is the GOT which resides at the begining of the data segment
720 * and is terminated with a -1. This one can be relocated in place.
721 * The second is the extra relocation entries tacked after the image's
722 * data segment. These require a little more processing as the entry is
723 * really an offset into the image which contains an offset into the
724 * image.
725 */
726 if (flags & FLAT_FLAG_GOTPIC) {
727 for (rp = (unsigned long *)datapos; *rp != 0xffffffff; rp++) {
728 unsigned long addr;
729 if (*rp) {
730 addr = calc_reloc(*rp, libinfo, id, 0);
731 if (addr == RELOC_FAILED) {
732 ret = -ENOEXEC;
733 goto err;
734 }
735 *rp = addr;
736 }
737 }
738 }
739
740 /*
741 * Now run through the relocation entries.
742 * We've got to be careful here as C++ produces relocatable zero
743 * entries in the constructor and destructor tables which are then
744 * tested for being not zero (which will always occur unless we're
745 * based from address zero). This causes an endless loop as __start
746 * is at zero. The solution used is to not relocate zero addresses.
747 * This has the negative side effect of not allowing a global data
748 * reference to be statically initialised to _stext (I've moved
749 * __start to address 4 so that is okay).
750 */
751 if (rev > OLD_FLAT_VERSION) {
752 unsigned long persistent = 0;
753 for (i=0; i < relocs; i++) {
754 unsigned long addr, relval;
755
756 /* Get the address of the pointer to be
757 relocated (of course, the address has to be
758 relocated first). */
759 relval = ntohl(reloc[i]);
760 if (flat_set_persistent (relval, &persistent))
761 continue;
762 addr = flat_get_relocate_addr(relval);
763 rp = (unsigned long *) calc_reloc(addr, libinfo, id, 1);
764 if (rp == (unsigned long *)RELOC_FAILED) {
765 ret = -ENOEXEC;
766 goto err;
767 }
768
769 /* Get the pointer's value. */
770 addr = flat_get_addr_from_rp(rp, relval, flags,
771 &persistent);
772 if (addr != 0) {
773 /*
774 * Do the relocation. PIC relocs in the data section are
775 * already in target order
776 */
777 if ((flags & FLAT_FLAG_GOTPIC) == 0)
778 addr = ntohl(addr);
779 addr = calc_reloc(addr, libinfo, id, 0);
780 if (addr == RELOC_FAILED) {
781 ret = -ENOEXEC;
782 goto err;
783 }
784
785 /* Write back the relocated pointer. */
786 flat_put_addr_at_rp(rp, addr, relval);
787 }
788 }
789 } else {
790 for (i=0; i < relocs; i++)
791 old_reloc(ntohl(reloc[i]));
792 }
793
794 flush_icache_range(start_code, end_code);
795
796 /* zero the BSS, BRK and stack areas */
797 memset((void*)(datapos + data_len), 0, bss_len +
798 (memp + memp_size - stack_len - /* end brk */
799 libinfo->lib_list[id].start_brk) + /* start brk */
800 stack_len);
801
802 return 0;
803 err:
804 return ret;
805 }
806
807
808 /****************************************************************************/
809 #ifdef CONFIG_BINFMT_SHARED_FLAT
810
811 /*
812 * Load a shared library into memory. The library gets its own data
813 * segment (including bss) but not argv/argc/environ.
814 */
815
816 static int load_flat_shared_library(int id, struct lib_info *libs)
817 {
818 struct linux_binprm bprm;
819 int res;
820 char buf[16];
821
822 /* Create the file name */
823 sprintf(buf, "/lib/lib%d.so", id);
824
825 /* Open the file up */
826 bprm.filename = buf;
827 bprm.file = open_exec(bprm.filename);
828 res = PTR_ERR(bprm.file);
829 if (IS_ERR(bprm.file))
830 return res;
831
832 bprm.cred = prepare_exec_creds();
833 res = -ENOMEM;
834 if (!bprm.cred)
835 goto out;
836
837 res = prepare_binprm(&bprm);
838
839 if (res <= (unsigned long)-4096)
840 res = load_flat_file(&bprm, libs, id, NULL);
841
842 abort_creds(bprm.cred);
843
844 out:
845 allow_write_access(bprm.file);
846 fput(bprm.file);
847
848 return(res);
849 }
850
851 #endif /* CONFIG_BINFMT_SHARED_FLAT */
852 /****************************************************************************/
853
854 /*
855 * These are the functions used to load flat style executables and shared
856 * libraries. There is no binary dependent code anywhere else.
857 */
858
859 static int load_flat_binary(struct linux_binprm * bprm, struct pt_regs * regs)
860 {
861 struct lib_info libinfo;
862 unsigned long p = bprm->p;
863 unsigned long stack_len;
864 unsigned long start_addr;
865 unsigned long *sp;
866 int res;
867 int i, j;
868
869 memset(&libinfo, 0, sizeof(libinfo));
870 /*
871 * We have to add the size of our arguments to our stack size
872 * otherwise it's too easy for users to create stack overflows
873 * by passing in a huge argument list. And yes, we have to be
874 * pedantic and include space for the argv/envp array as it may have
875 * a lot of entries.
876 */
877 #define TOP_OF_ARGS (PAGE_SIZE * MAX_ARG_PAGES - sizeof(void *))
878 stack_len = TOP_OF_ARGS - bprm->p; /* the strings */
879 stack_len += (bprm->argc + 1) * sizeof(char *); /* the argv array */
880 stack_len += (bprm->envc + 1) * sizeof(char *); /* the envp array */
881 stack_len += FLAT_DATA_ALIGN - 1; /* reserve for upcoming alignment */
882
883 res = load_flat_file(bprm, &libinfo, 0, &stack_len);
884 if (res > (unsigned long)-4096)
885 return res;
886
887 /* Update data segment pointers for all libraries */
888 for (i=0; i<MAX_SHARED_LIBS; i++)
889 if (libinfo.lib_list[i].loaded)
890 for (j=0; j<MAX_SHARED_LIBS; j++)
891 (-(j+1))[(unsigned long *)(libinfo.lib_list[i].start_data)] =
892 (libinfo.lib_list[j].loaded)?
893 libinfo.lib_list[j].start_data:UNLOADED_LIB;
894
895 install_exec_creds(bprm);
896 current->flags &= ~PF_FORKNOEXEC;
897
898 set_binfmt(&flat_format);
899
900 p = ((current->mm->context.end_brk + stack_len + 3) & ~3) - 4;
901 DBG_FLT("p=%x\n", (int)p);
902
903 /* copy the arg pages onto the stack, this could be more efficient :-) */
904 for (i = TOP_OF_ARGS - 1; i >= bprm->p; i--)
905 * (char *) --p =
906 ((char *) page_address(bprm->page[i/PAGE_SIZE]))[i % PAGE_SIZE];
907
908 sp = (unsigned long *) create_flat_tables(p, bprm);
909
910 /* Fake some return addresses to ensure the call chain will
911 * initialise library in order for us. We are required to call
912 * lib 1 first, then 2, ... and finally the main program (id 0).
913 */
914 start_addr = libinfo.lib_list[0].entry;
915
916 #ifdef CONFIG_BINFMT_SHARED_FLAT
917 for (i = MAX_SHARED_LIBS-1; i>0; i--) {
918 if (libinfo.lib_list[i].loaded) {
919 /* Push previos first to call address */
920 --sp; put_user(start_addr, sp);
921 start_addr = libinfo.lib_list[i].entry;
922 }
923 }
924 #endif
925
926 /* Stash our initial stack pointer into the mm structure */
927 current->mm->start_stack = (unsigned long )sp;
928
929 #ifdef FLAT_PLAT_INIT
930 FLAT_PLAT_INIT(regs);
931 #endif
932 DBG_FLT("start_thread(regs=0x%x, entry=0x%x, start_stack=0x%x)\n",
933 (int)regs, (int)start_addr, (int)current->mm->start_stack);
934
935 start_thread(regs, start_addr, current->mm->start_stack);
936
937 return 0;
938 }
939
940 /****************************************************************************/
941
942 static int __init init_flat_binfmt(void)
943 {
944 return register_binfmt(&flat_format);
945 }
946
947 /****************************************************************************/
948
949 core_initcall(init_flat_binfmt);
950
951 /****************************************************************************/
952
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