blob: ae8595d498569a72c6be2f4ce45d956326d33a9a [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/****************************************************************************/
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>
Linus Torvalds1da177e2005-04-16 15:20:36 -070019#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>
Luke Yang1ad3dcc2006-03-25 03:08:24 -080038#include <linux/syscalls.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070039
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
Linus Torvalds1da177e2005-04-16 15:20:36 -070080static 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;
422 unsigned long memp = 0; /* for finding the brk area */
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;
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800429 int ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700430
431 hdr = ((struct flat_hdr *) bprm->buf); /* exec-header */
Josef "Jeff" Sipek0f7fc9e2006-12-08 02:36:35 -0800432 inode = bprm->file->f_path.dentry->d_inode;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700433
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
Greg Ungerer845884d2006-01-10 16:59:37 +1000446 if (strncmp(hdr->magic, "bFLT", 4)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700447 /*
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))
Greg Ungerer845884d2006-01-10 16:59:37 +1000453 printk("BINFMT_FLAT: bad header magic\n");
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800454 ret = -ENOEXEC;
455 goto err;
Greg Ungerer845884d2006-01-10 16:59:37 +1000456 }
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);
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800463 ret = -ENOEXEC;
464 goto err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700465 }
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);
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800471 ret = -ENOEXEC;
472 goto err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700473 }
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");
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800485 ret = -ENOEXEC;
486 goto err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700487 }
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;
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800498 if (data_len + bss_len > rlim) {
499 ret = -ENOMEM;
500 goto err;
501 }
502
Linus Torvalds1da177e2005-04-16 15:20:36 -0700503 /* Flush all traces of the currently running executable */
504 if (id == 0) {
505 result = flush_old_exec(bprm);
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800506 if (result) {
507 ret = result;
Andrew Mortondf889122006-05-20 15:00:01 -0700508 goto err;
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800509 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700510
511 /* OK, This is the point of no return */
Malcolm Parsonsfcc18e82006-06-26 11:49:41 +1000512 set_personality(PER_LINUX_32BIT);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700513 }
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);
Greg Ungerer213b24c2005-09-02 10:42:52 +1000533 textpos = do_mmap(bprm->file, 0, text_len, PROT_READ|PROT_EXEC, MAP_PRIVATE, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700534 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);
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800539 ret = textpos;
Andrew Mortondf889122006-05-20 15:00:01 -0700540 goto err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700541 }
542
543 down_write(&current->mm->mmap_sem);
544 realdatastart = do_mmap(0, 0, data_len + extra +
545 MAX_SHARED_LIBS * sizeof(unsigned long),
Yoshinori Sato8f5bb042005-06-06 14:46:32 -0700546 PROT_READ|PROT_WRITE|PROT_EXEC, MAP_PRIVATE, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700547 up_write(&current->mm->mmap_sem);
548
549 if (realdatastart == 0 || realdatastart >= (unsigned long)-4096) {
550 if (!realdatastart)
551 realdatastart = (unsigned long) -ENOMEM;
552 printk("Unable to allocate RAM for process data, errno %d\n",
553 (int)-datapos);
554 do_munmap(current->mm, textpos, text_len);
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800555 ret = realdatastart;
Andrew Mortondf889122006-05-20 15:00:01 -0700556 goto err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700557 }
558 datapos = realdatastart + MAX_SHARED_LIBS * sizeof(unsigned long);
559
560 DBG_FLT("BINFMT_FLAT: Allocated data+bss+stack (%d bytes): %x\n",
561 (int)(data_len + bss_len + stack_len), (int)datapos);
562
563 fpos = ntohl(hdr->data_start);
564#ifdef CONFIG_BINFMT_ZFLAT
565 if (flags & FLAT_FLAG_GZDATA) {
566 result = decompress_exec(bprm, fpos, (char *) datapos,
567 data_len + (relocs * sizeof(unsigned long)), 0);
568 } else
569#endif
570 {
571 result = bprm->file->f_op->read(bprm->file, (char *) datapos,
572 data_len + (relocs * sizeof(unsigned long)), &fpos);
573 }
574 if (result >= (unsigned long)-4096) {
575 printk("Unable to read data+bss, errno %d\n", (int)-result);
576 do_munmap(current->mm, textpos, text_len);
577 do_munmap(current->mm, realdatastart, data_len + extra);
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800578 ret = result;
Andrew Mortondf889122006-05-20 15:00:01 -0700579 goto err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700580 }
581
582 reloc = (unsigned long *) (datapos+(ntohl(hdr->reloc_start)-text_len));
583 memp = realdatastart;
584
585 } else {
586
587 down_write(&current->mm->mmap_sem);
588 textpos = do_mmap(0, 0, text_len + data_len + extra +
589 MAX_SHARED_LIBS * sizeof(unsigned long),
Yoshinori Sato8f5bb042005-06-06 14:46:32 -0700590 PROT_READ | PROT_EXEC | PROT_WRITE, MAP_PRIVATE, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700591 up_write(&current->mm->mmap_sem);
592 if (!textpos || textpos >= (unsigned long) -4096) {
593 if (!textpos)
594 textpos = (unsigned long) -ENOMEM;
595 printk("Unable to allocate RAM for process text/data, errno %d\n",
596 (int)-textpos);
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800597 ret = textpos;
Andrew Mortondf889122006-05-20 15:00:01 -0700598 goto err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700599 }
600
601 realdatastart = textpos + ntohl(hdr->data_start);
602 datapos = realdatastart + MAX_SHARED_LIBS * sizeof(unsigned long);
603 reloc = (unsigned long *) (textpos + ntohl(hdr->reloc_start) +
604 MAX_SHARED_LIBS * sizeof(unsigned long));
605 memp = textpos;
606
607#ifdef CONFIG_BINFMT_ZFLAT
608 /*
609 * load it all in and treat it like a RAM load from now on
610 */
611 if (flags & FLAT_FLAG_GZIP) {
612 result = decompress_exec(bprm, sizeof (struct flat_hdr),
613 (((char *) textpos) + sizeof (struct flat_hdr)),
614 (text_len + data_len + (relocs * sizeof(unsigned long))
615 - sizeof (struct flat_hdr)),
616 0);
617 memmove((void *) datapos, (void *) realdatastart,
618 data_len + (relocs * sizeof(unsigned long)));
619 } else if (flags & FLAT_FLAG_GZDATA) {
620 fpos = 0;
621 result = bprm->file->f_op->read(bprm->file,
622 (char *) textpos, text_len, &fpos);
623 if (result < (unsigned long) -4096)
624 result = decompress_exec(bprm, text_len, (char *) datapos,
625 data_len + (relocs * sizeof(unsigned long)), 0);
626 }
627 else
628#endif
629 {
630 fpos = 0;
631 result = bprm->file->f_op->read(bprm->file,
632 (char *) textpos, text_len, &fpos);
633 if (result < (unsigned long) -4096) {
634 fpos = ntohl(hdr->data_start);
635 result = bprm->file->f_op->read(bprm->file, (char *) datapos,
636 data_len + (relocs * sizeof(unsigned long)), &fpos);
637 }
638 }
639 if (result >= (unsigned long)-4096) {
640 printk("Unable to read code+data+bss, errno %d\n",(int)-result);
641 do_munmap(current->mm, textpos, text_len + data_len + extra +
642 MAX_SHARED_LIBS * sizeof(unsigned long));
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800643 ret = result;
Andrew Mortondf889122006-05-20 15:00:01 -0700644 goto err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700645 }
646 }
647
648 if (flags & FLAT_FLAG_KTRACE)
649 printk("Mapping is %x, Entry point is %x, data_start is %x\n",
650 (int)textpos, 0x00ffffff&ntohl(hdr->entry), ntohl(hdr->data_start));
651
652 /* The main program needs a little extra setup in the task structure */
653 start_code = textpos + sizeof (struct flat_hdr);
654 end_code = textpos + text_len;
655 if (id == 0) {
656 current->mm->start_code = start_code;
657 current->mm->end_code = end_code;
658 current->mm->start_data = datapos;
659 current->mm->end_data = datapos + data_len;
660 /*
661 * set up the brk stuff, uses any slack left in data/bss/stack
662 * allocation. We put the brk after the bss (between the bss
663 * and stack) like other platforms.
664 */
665 current->mm->start_brk = datapos + data_len + bss_len;
666 current->mm->brk = (current->mm->start_brk + 3) & ~3;
667 current->mm->context.end_brk = memp + ksize((void *) memp) - stack_len;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700668 }
669
670 if (flags & FLAT_FLAG_KTRACE)
671 printk("%s %s: TEXT=%x-%x DATA=%x-%x BSS=%x-%x\n",
672 id ? "Lib" : "Load", bprm->filename,
673 (int) start_code, (int) end_code,
674 (int) datapos,
675 (int) (datapos + data_len),
676 (int) (datapos + data_len),
677 (int) (((datapos + data_len + bss_len) + 3) & ~3));
678
679 text_len -= sizeof(struct flat_hdr); /* the real code len */
680
681 /* Store the current module values into the global library structure */
682 libinfo->lib_list[id].start_code = start_code;
683 libinfo->lib_list[id].start_data = datapos;
684 libinfo->lib_list[id].start_brk = datapos + data_len + bss_len;
685 libinfo->lib_list[id].text_len = text_len;
686 libinfo->lib_list[id].loaded = 1;
687 libinfo->lib_list[id].entry = (0x00ffffff & ntohl(hdr->entry)) + textpos;
688 libinfo->lib_list[id].build_date = ntohl(hdr->build_date);
689
690 /*
691 * We just load the allocations into some temporary memory to
692 * help simplify all this mumbo jumbo
693 *
694 * We've got two different sections of relocation entries.
695 * The first is the GOT which resides at the begining of the data segment
696 * and is terminated with a -1. This one can be relocated in place.
697 * The second is the extra relocation entries tacked after the image's
698 * data segment. These require a little more processing as the entry is
699 * really an offset into the image which contains an offset into the
700 * image.
701 */
702 if (flags & FLAT_FLAG_GOTPIC) {
703 for (rp = (unsigned long *)datapos; *rp != 0xffffffff; rp++) {
704 unsigned long addr;
705 if (*rp) {
706 addr = calc_reloc(*rp, libinfo, id, 0);
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800707 if (addr == RELOC_FAILED) {
708 ret = -ENOEXEC;
Andrew Mortondf889122006-05-20 15:00:01 -0700709 goto err;
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800710 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700711 *rp = addr;
712 }
713 }
714 }
715
716 /*
717 * Now run through the relocation entries.
718 * We've got to be careful here as C++ produces relocatable zero
719 * entries in the constructor and destructor tables which are then
720 * tested for being not zero (which will always occur unless we're
721 * based from address zero). This causes an endless loop as __start
722 * is at zero. The solution used is to not relocate zero addresses.
723 * This has the negative side effect of not allowing a global data
724 * reference to be statically initialised to _stext (I've moved
725 * __start to address 4 so that is okay).
726 */
727 if (rev > OLD_FLAT_VERSION) {
728 for (i=0; i < relocs; i++) {
729 unsigned long addr, relval;
730
731 /* Get the address of the pointer to be
732 relocated (of course, the address has to be
733 relocated first). */
734 relval = ntohl(reloc[i]);
735 addr = flat_get_relocate_addr(relval);
736 rp = (unsigned long *) calc_reloc(addr, libinfo, id, 1);
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800737 if (rp == (unsigned long *)RELOC_FAILED) {
738 ret = -ENOEXEC;
Andrew Mortondf889122006-05-20 15:00:01 -0700739 goto err;
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800740 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700741
742 /* Get the pointer's value. */
743 addr = flat_get_addr_from_rp(rp, relval, flags);
744 if (addr != 0) {
745 /*
746 * Do the relocation. PIC relocs in the data section are
747 * already in target order
748 */
749 if ((flags & FLAT_FLAG_GOTPIC) == 0)
750 addr = ntohl(addr);
751 addr = calc_reloc(addr, libinfo, id, 0);
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800752 if (addr == RELOC_FAILED) {
753 ret = -ENOEXEC;
Andrew Mortondf889122006-05-20 15:00:01 -0700754 goto err;
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800755 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700756
757 /* Write back the relocated pointer. */
758 flat_put_addr_at_rp(rp, addr, relval);
759 }
760 }
761 } else {
762 for (i=0; i < relocs; i++)
763 old_reloc(ntohl(reloc[i]));
764 }
765
766 flush_icache_range(start_code, end_code);
767
768 /* zero the BSS, BRK and stack areas */
769 memset((void*)(datapos + data_len), 0, bss_len +
770 (memp + ksize((void *) memp) - stack_len - /* end brk */
771 libinfo->lib_list[id].start_brk) + /* start brk */
772 stack_len);
773
774 return 0;
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800775err:
776 return ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700777}
778
779
780/****************************************************************************/
781#ifdef CONFIG_BINFMT_SHARED_FLAT
782
783/*
784 * Load a shared library into memory. The library gets its own data
785 * segment (including bss) but not argv/argc/environ.
786 */
787
788static int load_flat_shared_library(int id, struct lib_info *libs)
789{
790 struct linux_binprm bprm;
791 int res;
792 char buf[16];
793
794 /* Create the file name */
795 sprintf(buf, "/lib/lib%d.so", id);
796
797 /* Open the file up */
798 bprm.filename = buf;
799 bprm.file = open_exec(bprm.filename);
800 res = PTR_ERR(bprm.file);
801 if (IS_ERR(bprm.file))
802 return res;
803
804 res = prepare_binprm(&bprm);
805
806 if (res <= (unsigned long)-4096)
807 res = load_flat_file(&bprm, libs, id, NULL);
808 if (bprm.file) {
809 allow_write_access(bprm.file);
810 fput(bprm.file);
811 bprm.file = NULL;
812 }
813 return(res);
814}
815
816#endif /* CONFIG_BINFMT_SHARED_FLAT */
817/****************************************************************************/
818
819/*
820 * These are the functions used to load flat style executables and shared
821 * libraries. There is no binary dependent code anywhere else.
822 */
823
824static int load_flat_binary(struct linux_binprm * bprm, struct pt_regs * regs)
825{
826 struct lib_info libinfo;
827 unsigned long p = bprm->p;
828 unsigned long stack_len;
829 unsigned long start_addr;
830 unsigned long *sp;
831 int res;
832 int i, j;
833
834 memset(&libinfo, 0, sizeof(libinfo));
835 /*
836 * We have to add the size of our arguments to our stack size
837 * otherwise it's too easy for users to create stack overflows
838 * by passing in a huge argument list. And yes, we have to be
839 * pedantic and include space for the argv/envp array as it may have
840 * a lot of entries.
841 */
842#define TOP_OF_ARGS (PAGE_SIZE * MAX_ARG_PAGES - sizeof(void *))
843 stack_len = TOP_OF_ARGS - bprm->p; /* the strings */
844 stack_len += (bprm->argc + 1) * sizeof(char *); /* the argv array */
845 stack_len += (bprm->envc + 1) * sizeof(char *); /* the envp array */
846
847
848 res = load_flat_file(bprm, &libinfo, 0, &stack_len);
849 if (res > (unsigned long)-4096)
850 return res;
851
852 /* Update data segment pointers for all libraries */
853 for (i=0; i<MAX_SHARED_LIBS; i++)
854 if (libinfo.lib_list[i].loaded)
855 for (j=0; j<MAX_SHARED_LIBS; j++)
856 (-(j+1))[(unsigned long *)(libinfo.lib_list[i].start_data)] =
857 (libinfo.lib_list[j].loaded)?
858 libinfo.lib_list[j].start_data:UNLOADED_LIB;
859
860 compute_creds(bprm);
861 current->flags &= ~PF_FORKNOEXEC;
862
863 set_binfmt(&flat_format);
864
865 p = ((current->mm->context.end_brk + stack_len + 3) & ~3) - 4;
866 DBG_FLT("p=%x\n", (int)p);
867
868 /* copy the arg pages onto the stack, this could be more efficient :-) */
869 for (i = TOP_OF_ARGS - 1; i >= bprm->p; i--)
870 * (char *) --p =
871 ((char *) page_address(bprm->page[i/PAGE_SIZE]))[i % PAGE_SIZE];
872
873 sp = (unsigned long *) create_flat_tables(p, bprm);
874
875 /* Fake some return addresses to ensure the call chain will
876 * initialise library in order for us. We are required to call
877 * lib 1 first, then 2, ... and finally the main program (id 0).
878 */
879 start_addr = libinfo.lib_list[0].entry;
880
881#ifdef CONFIG_BINFMT_SHARED_FLAT
882 for (i = MAX_SHARED_LIBS-1; i>0; i--) {
883 if (libinfo.lib_list[i].loaded) {
884 /* Push previos first to call address */
885 --sp; put_user(start_addr, sp);
886 start_addr = libinfo.lib_list[i].entry;
887 }
888 }
889#endif
890
891 /* Stash our initial stack pointer into the mm structure */
892 current->mm->start_stack = (unsigned long )sp;
893
894
895 DBG_FLT("start_thread(regs=0x%x, entry=0x%x, start_stack=0x%x)\n",
896 (int)regs, (int)start_addr, (int)current->mm->start_stack);
897
898 start_thread(regs, start_addr, current->mm->start_stack);
899
900 if (current->ptrace & PT_PTRACED)
901 send_sig(SIGTRAP, current, 0);
902
903 return 0;
904}
905
906/****************************************************************************/
907
908static int __init init_flat_binfmt(void)
909{
910 return register_binfmt(&flat_format);
911}
912
913static void __exit exit_flat_binfmt(void)
914{
915 unregister_binfmt(&flat_format);
916}
917
918/****************************************************************************/
919
920core_initcall(init_flat_binfmt);
921module_exit(exit_flat_binfmt);
922
923/****************************************************************************/