blob: 7bbd5c6b37257ad5beba8180f9249d6f4eb1a6f3 [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>
Linus Torvalds1da177e2005-04-16 15:20:36 -070023#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>
Luke Yang1ad3dcc2006-03-25 03:08:24 -080037#include <linux/syscalls.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070038
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
45/****************************************************************************/
46
47#if 0
48#define DEBUG 1
49#endif
50
51#ifdef DEBUG
52#define DBG_FLT(a...) printk(a)
53#else
54#define DBG_FLT(a...)
55#endif
56
57#define RELOC_FAILED 0xff00ff01 /* Relocation incorrect somewhere */
58#define UNLOADED_LIB 0x7ff000ff /* Placeholder for unused library */
59
60struct lib_info {
61 struct {
62 unsigned long start_code; /* Start of text segment */
63 unsigned long start_data; /* Start of data segment */
64 unsigned long start_brk; /* End of data segment */
65 unsigned long text_len; /* Length of text segment */
66 unsigned long entry; /* Start address for this module */
67 unsigned long build_date; /* When this one was compiled */
68 short loaded; /* Has this library been loaded? */
69 } lib_list[MAX_SHARED_LIBS];
70};
71
72#ifdef CONFIG_BINFMT_SHARED_FLAT
73static int load_flat_shared_library(int id, struct lib_info *p);
74#endif
75
76static int load_flat_binary(struct linux_binprm *, struct pt_regs * regs);
Neil Horman7dc0b222007-10-16 23:26:34 -070077static int flat_core_dump(long signr, struct pt_regs *regs, struct file *file, unsigned long limit);
Linus Torvalds1da177e2005-04-16 15:20:36 -070078
Linus Torvalds1da177e2005-04-16 15:20:36 -070079static struct linux_binfmt flat_format = {
80 .module = THIS_MODULE,
81 .load_binary = load_flat_binary,
82 .core_dump = flat_core_dump,
83 .min_coredump = PAGE_SIZE
84};
85
86/****************************************************************************/
87/*
88 * Routine writes a core dump image in the current directory.
89 * Currently only a stub-function.
90 */
91
Neil Horman7dc0b222007-10-16 23:26:34 -070092static int flat_core_dump(long signr, struct pt_regs *regs, struct file *file, unsigned long limit)
Linus Torvalds1da177e2005-04-16 15:20:36 -070093{
94 printk("Process %s:%d received signr %d and should have core dumped\n",
95 current->comm, current->pid, (int) signr);
96 return(1);
97}
98
99/****************************************************************************/
100/*
101 * create_flat_tables() parses the env- and arg-strings in new user
102 * memory and creates the pointer tables from them, and puts their
103 * addresses on the "stack", returning the new stack pointer value.
104 */
105
106static unsigned long create_flat_tables(
107 unsigned long pp,
108 struct linux_binprm * bprm)
109{
110 unsigned long *argv,*envp;
111 unsigned long * sp;
112 char * p = (char*)pp;
113 int argc = bprm->argc;
114 int envc = bprm->envc;
Andrew Morton0e647c02007-10-16 23:27:26 -0700115 char uninitialized_var(dummy);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700116
117 sp = (unsigned long *) ((-(unsigned long)sizeof(char *))&(unsigned long) p);
118
119 sp -= envc+1;
120 envp = sp;
121 sp -= argc+1;
122 argv = sp;
123
124 flat_stack_align(sp);
125 if (flat_argvp_envp_on_stack()) {
126 --sp; put_user((unsigned long) envp, sp);
127 --sp; put_user((unsigned long) argv, sp);
128 }
129
130 put_user(argc,--sp);
131 current->mm->arg_start = (unsigned long) p;
132 while (argc-->0) {
133 put_user((unsigned long) p, argv++);
134 do {
135 get_user(dummy, p); p++;
136 } while (dummy);
137 }
138 put_user((unsigned long) NULL, argv);
139 current->mm->arg_end = current->mm->env_start = (unsigned long) p;
140 while (envc-->0) {
141 put_user((unsigned long)p, envp); envp++;
142 do {
143 get_user(dummy, p); p++;
144 } while (dummy);
145 }
146 put_user((unsigned long) NULL, envp);
147 current->mm->env_end = (unsigned long) p;
148 return (unsigned long)sp;
149}
150
151/****************************************************************************/
152
153#ifdef CONFIG_BINFMT_ZFLAT
154
155#include <linux/zlib.h>
156
157#define LBUFSIZE 4000
158
159/* gzip flag byte */
160#define ASCII_FLAG 0x01 /* bit 0 set: file probably ASCII text */
161#define CONTINUATION 0x02 /* bit 1 set: continuation of multi-part gzip file */
162#define EXTRA_FIELD 0x04 /* bit 2 set: extra field present */
163#define ORIG_NAME 0x08 /* bit 3 set: original file name present */
164#define COMMENT 0x10 /* bit 4 set: file comment present */
165#define ENCRYPTED 0x20 /* bit 5 set: file is encrypted */
166#define RESERVED 0xC0 /* bit 6,7: reserved */
167
168static int decompress_exec(
169 struct linux_binprm *bprm,
170 unsigned long offset,
171 char *dst,
172 long len,
173 int fd)
174{
175 unsigned char *buf;
176 z_stream strm;
177 loff_t fpos;
178 int ret, retval;
179
180 DBG_FLT("decompress_exec(offset=%x,buf=%x,len=%x)\n",(int)offset, (int)dst, (int)len);
181
182 memset(&strm, 0, sizeof(strm));
183 strm.workspace = kmalloc(zlib_inflate_workspacesize(), GFP_KERNEL);
184 if (strm.workspace == NULL) {
185 DBG_FLT("binfmt_flat: no memory for decompress workspace\n");
186 return -ENOMEM;
187 }
188 buf = kmalloc(LBUFSIZE, GFP_KERNEL);
189 if (buf == NULL) {
190 DBG_FLT("binfmt_flat: no memory for read buffer\n");
191 retval = -ENOMEM;
192 goto out_free;
193 }
194
195 /* Read in first chunk of data and parse gzip header. */
196 fpos = offset;
197 ret = bprm->file->f_op->read(bprm->file, buf, LBUFSIZE, &fpos);
198
199 strm.next_in = buf;
200 strm.avail_in = ret;
201 strm.total_in = 0;
202
203 retval = -ENOEXEC;
204
205 /* Check minimum size -- gzip header */
206 if (ret < 10) {
207 DBG_FLT("binfmt_flat: file too small?\n");
208 goto out_free_buf;
209 }
210
211 /* Check gzip magic number */
212 if ((buf[0] != 037) || ((buf[1] != 0213) && (buf[1] != 0236))) {
213 DBG_FLT("binfmt_flat: unknown compression magic?\n");
214 goto out_free_buf;
215 }
216
217 /* Check gzip method */
218 if (buf[2] != 8) {
219 DBG_FLT("binfmt_flat: unknown compression method?\n");
220 goto out_free_buf;
221 }
222 /* Check gzip flags */
223 if ((buf[3] & ENCRYPTED) || (buf[3] & CONTINUATION) ||
224 (buf[3] & RESERVED)) {
225 DBG_FLT("binfmt_flat: unknown flags?\n");
226 goto out_free_buf;
227 }
228
229 ret = 10;
230 if (buf[3] & EXTRA_FIELD) {
231 ret += 2 + buf[10] + (buf[11] << 8);
Volodymyr G. Lukiianykf4cfb182008-10-15 22:01:15 -0700232 if (unlikely(LBUFSIZE <= ret)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700233 DBG_FLT("binfmt_flat: buffer overflow (EXTRA)?\n");
234 goto out_free_buf;
235 }
236 }
237 if (buf[3] & ORIG_NAME) {
Volodymyr G. Lukiianykf4cfb182008-10-15 22:01:15 -0700238 while (ret < LBUFSIZE && buf[ret++] != 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700239 ;
240 if (unlikely(LBUFSIZE == ret)) {
241 DBG_FLT("binfmt_flat: buffer overflow (ORIG_NAME)?\n");
242 goto out_free_buf;
243 }
244 }
245 if (buf[3] & COMMENT) {
Volodymyr G. Lukiianykf4cfb182008-10-15 22:01:15 -0700246 while (ret < LBUFSIZE && buf[ret++] != 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700247 ;
248 if (unlikely(LBUFSIZE == ret)) {
249 DBG_FLT("binfmt_flat: buffer overflow (COMMENT)?\n");
250 goto out_free_buf;
251 }
252 }
253
254 strm.next_in += ret;
255 strm.avail_in -= ret;
256
257 strm.next_out = dst;
258 strm.avail_out = len;
259 strm.total_out = 0;
260
261 if (zlib_inflateInit2(&strm, -MAX_WBITS) != Z_OK) {
262 DBG_FLT("binfmt_flat: zlib init failed?\n");
263 goto out_free_buf;
264 }
265
266 while ((ret = zlib_inflate(&strm, Z_NO_FLUSH)) == Z_OK) {
267 ret = bprm->file->f_op->read(bprm->file, buf, LBUFSIZE, &fpos);
268 if (ret <= 0)
269 break;
270 if (ret >= (unsigned long) -4096)
271 break;
272 len -= ret;
273
274 strm.next_in = buf;
275 strm.avail_in = ret;
276 strm.total_in = 0;
277 }
278
279 if (ret < 0) {
280 DBG_FLT("binfmt_flat: decompression failed (%d), %s\n",
281 ret, strm.msg);
282 goto out_zlib;
283 }
284
285 retval = 0;
286out_zlib:
287 zlib_inflateEnd(&strm);
288out_free_buf:
289 kfree(buf);
290out_free:
291 kfree(strm.workspace);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700292 return retval;
293}
294
295#endif /* CONFIG_BINFMT_ZFLAT */
296
297/****************************************************************************/
298
299static unsigned long
300calc_reloc(unsigned long r, struct lib_info *p, int curid, int internalp)
301{
302 unsigned long addr;
303 int id;
304 unsigned long start_brk;
305 unsigned long start_data;
306 unsigned long text_len;
307 unsigned long start_code;
308
309#ifdef CONFIG_BINFMT_SHARED_FLAT
310 if (r == 0)
311 id = curid; /* Relocs of 0 are always self referring */
312 else {
313 id = (r >> 24) & 0xff; /* Find ID for this reloc */
314 r &= 0x00ffffff; /* Trim ID off here */
315 }
316 if (id >= MAX_SHARED_LIBS) {
317 printk("BINFMT_FLAT: reference 0x%x to shared library %d",
318 (unsigned) r, id);
319 goto failed;
320 }
321 if (curid != id) {
322 if (internalp) {
323 printk("BINFMT_FLAT: reloc address 0x%x not in same module "
324 "(%d != %d)", (unsigned) r, curid, id);
325 goto failed;
326 } else if ( ! p->lib_list[id].loaded &&
327 load_flat_shared_library(id, p) > (unsigned long) -4096) {
328 printk("BINFMT_FLAT: failed to load library %d", id);
329 goto failed;
330 }
331 /* Check versioning information (i.e. time stamps) */
332 if (p->lib_list[id].build_date && p->lib_list[curid].build_date &&
333 p->lib_list[curid].build_date < p->lib_list[id].build_date) {
334 printk("BINFMT_FLAT: library %d is younger than %d", id, curid);
335 goto failed;
336 }
337 }
338#else
339 id = 0;
340#endif
341
342 start_brk = p->lib_list[id].start_brk;
343 start_data = p->lib_list[id].start_data;
344 start_code = p->lib_list[id].start_code;
345 text_len = p->lib_list[id].text_len;
346
347 if (!flat_reloc_valid(r, start_brk - start_data + text_len)) {
348 printk("BINFMT_FLAT: reloc outside program 0x%x (0 - 0x%x/0x%x)",
349 (int) r,(int)(start_brk-start_code),(int)text_len);
350 goto failed;
351 }
352
353 if (r < text_len) /* In text segment */
354 addr = r + start_code;
355 else /* In data segment */
356 addr = r - text_len + start_data;
357
358 /* Range checked already above so doing the range tests is redundant...*/
359 return(addr);
360
361failed:
362 printk(", killing %s!\n", current->comm);
363 send_sig(SIGSEGV, current, 0);
364
365 return RELOC_FAILED;
366}
367
368/****************************************************************************/
369
370void old_reloc(unsigned long rl)
371{
372#ifdef DEBUG
373 char *segment[] = { "TEXT", "DATA", "BSS", "*UNKNOWN*" };
374#endif
375 flat_v2_reloc_t r;
376 unsigned long *ptr;
377
378 r.value = rl;
379#if defined(CONFIG_COLDFIRE)
380 ptr = (unsigned long *) (current->mm->start_code + r.reloc.offset);
381#else
382 ptr = (unsigned long *) (current->mm->start_data + r.reloc.offset);
383#endif
384
385#ifdef DEBUG
386 printk("Relocation of variable at DATASEG+%x "
387 "(address %p, currently %x) into segment %s\n",
388 r.reloc.offset, ptr, (int)*ptr, segment[r.reloc.type]);
389#endif
390
391 switch (r.reloc.type) {
392 case OLD_FLAT_RELOC_TYPE_TEXT:
393 *ptr += current->mm->start_code;
394 break;
395 case OLD_FLAT_RELOC_TYPE_DATA:
396 *ptr += current->mm->start_data;
397 break;
398 case OLD_FLAT_RELOC_TYPE_BSS:
399 *ptr += current->mm->end_data;
400 break;
401 default:
402 printk("BINFMT_FLAT: Unknown relocation type=%x\n", r.reloc.type);
403 break;
404 }
405
406#ifdef DEBUG
407 printk("Relocation became %x\n", (int)*ptr);
408#endif
409}
410
411/****************************************************************************/
412
413static int load_flat_file(struct linux_binprm * bprm,
414 struct lib_info *libinfo, int id, unsigned long *extra_stack)
415{
416 struct flat_hdr * hdr;
417 unsigned long textpos = 0, datapos = 0, result;
418 unsigned long realdatastart = 0;
419 unsigned long text_len, data_len, bss_len, stack_len, flags;
Greg Ungerer72613e5f2007-02-07 12:03:08 +1000420 unsigned long len, reallen, memp = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700421 unsigned long extra, rlim;
422 unsigned long *reloc = 0, *rp;
423 struct inode *inode;
424 int i, rev, relocs = 0;
425 loff_t fpos;
426 unsigned long start_code, end_code;
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800427 int ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700428
429 hdr = ((struct flat_hdr *) bprm->buf); /* exec-header */
Josef "Jeff" Sipek0f7fc9e2006-12-08 02:36:35 -0800430 inode = bprm->file->f_path.dentry->d_inode;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700431
432 text_len = ntohl(hdr->data_start);
433 data_len = ntohl(hdr->data_end) - ntohl(hdr->data_start);
434 bss_len = ntohl(hdr->bss_end) - ntohl(hdr->data_end);
435 stack_len = ntohl(hdr->stack_size);
436 if (extra_stack) {
437 stack_len += *extra_stack;
438 *extra_stack = stack_len;
439 }
440 relocs = ntohl(hdr->reloc_count);
441 flags = ntohl(hdr->flags);
442 rev = ntohl(hdr->rev);
443
Greg Ungerer845884d2006-01-10 16:59:37 +1000444 if (strncmp(hdr->magic, "bFLT", 4)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700445 /*
Mike Frysingere2a366d2008-02-14 19:31:29 -0800446 * Previously, here was a printk to tell people
447 * "BINFMT_FLAT: bad header magic".
448 * But for the kernel which also use ELF FD-PIC format, this
449 * error message is confusing.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700450 * because a lot of people do not manage to produce good
Linus Torvalds1da177e2005-04-16 15:20:36 -0700451 */
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800452 ret = -ENOEXEC;
453 goto err;
Greg Ungerer845884d2006-01-10 16:59:37 +1000454 }
455
456 if (flags & FLAT_FLAG_KTRACE)
457 printk("BINFMT_FLAT: Loading file: %s\n", bprm->filename);
458
459 if (rev != FLAT_VERSION && rev != OLD_FLAT_VERSION) {
Andrew Morton0e647c02007-10-16 23:27:26 -0700460 printk("BINFMT_FLAT: bad flat file version 0x%x (supported "
461 "0x%lx and 0x%lx)\n",
462 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 */
Andrew Morton0e647c02007-10-16 23:27:26 -0700518 extra = max_t(unsigned long, bss_len + stack_len,
519 relocs * sizeof(unsigned long));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700520
521 /*
522 * there are a couple of cases here, the separate code/data
523 * case, and then the fully copied to RAM case which lumps
524 * it all together.
525 */
526 if ((flags & (FLAT_FLAG_RAM|FLAT_FLAG_GZIP)) == 0) {
527 /*
528 * this should give us a ROM ptr, but if it doesn't we don't
529 * really care
530 */
531 DBG_FLT("BINFMT_FLAT: ROM mapping of file (we hope)\n");
532
533 down_write(&current->mm->mmap_sem);
Matt Helsley925d1c42008-04-29 01:01:36 -0700534 textpos = do_mmap(bprm->file, 0, text_len, PROT_READ|PROT_EXEC,
535 MAP_PRIVATE|MAP_EXECUTABLE, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700536 up_write(&current->mm->mmap_sem);
537 if (!textpos || textpos >= (unsigned long) -4096) {
538 if (!textpos)
539 textpos = (unsigned long) -ENOMEM;
540 printk("Unable to mmap process text, errno %d\n", (int)-textpos);
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800541 ret = textpos;
Andrew Mortondf889122006-05-20 15:00:01 -0700542 goto err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700543 }
544
Greg Ungerer72613e5f2007-02-07 12:03:08 +1000545 len = data_len + extra + MAX_SHARED_LIBS * sizeof(unsigned long);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700546 down_write(&current->mm->mmap_sem);
Greg Ungerer72613e5f2007-02-07 12:03:08 +1000547 realdatastart = do_mmap(0, 0, len,
548 PROT_READ|PROT_WRITE|PROT_EXEC, MAP_PRIVATE, 0);
549 /* Remap to use all availabe slack region space */
550 if (realdatastart && (realdatastart < (unsigned long)-4096)) {
Pekka Enbergd100d142008-06-05 22:46:46 -0700551 reallen = kobjsize((void *)realdatastart);
Greg Ungerer72613e5f2007-02-07 12:03:08 +1000552 if (reallen > len) {
553 realdatastart = do_mremap(realdatastart, len,
554 reallen, MREMAP_FIXED, realdatastart);
555 }
556 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700557 up_write(&current->mm->mmap_sem);
558
559 if (realdatastart == 0 || realdatastart >= (unsigned long)-4096) {
560 if (!realdatastart)
561 realdatastart = (unsigned long) -ENOMEM;
562 printk("Unable to allocate RAM for process data, errno %d\n",
Greg Ungererc287ef12007-06-08 13:46:43 -0700563 (int)-realdatastart);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700564 do_munmap(current->mm, textpos, text_len);
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800565 ret = realdatastart;
Andrew Mortondf889122006-05-20 15:00:01 -0700566 goto err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700567 }
568 datapos = realdatastart + MAX_SHARED_LIBS * sizeof(unsigned long);
569
570 DBG_FLT("BINFMT_FLAT: Allocated data+bss+stack (%d bytes): %x\n",
571 (int)(data_len + bss_len + stack_len), (int)datapos);
572
573 fpos = ntohl(hdr->data_start);
574#ifdef CONFIG_BINFMT_ZFLAT
575 if (flags & FLAT_FLAG_GZDATA) {
576 result = decompress_exec(bprm, fpos, (char *) datapos,
577 data_len + (relocs * sizeof(unsigned long)), 0);
578 } else
579#endif
580 {
581 result = bprm->file->f_op->read(bprm->file, (char *) datapos,
582 data_len + (relocs * sizeof(unsigned long)), &fpos);
583 }
584 if (result >= (unsigned long)-4096) {
585 printk("Unable to read data+bss, errno %d\n", (int)-result);
586 do_munmap(current->mm, textpos, text_len);
587 do_munmap(current->mm, realdatastart, data_len + extra);
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800588 ret = result;
Andrew Mortondf889122006-05-20 15:00:01 -0700589 goto err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700590 }
591
592 reloc = (unsigned long *) (datapos+(ntohl(hdr->reloc_start)-text_len));
593 memp = realdatastart;
594
595 } else {
596
Greg Ungerer72613e5f2007-02-07 12:03:08 +1000597 len = text_len + data_len + extra + MAX_SHARED_LIBS * sizeof(unsigned long);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700598 down_write(&current->mm->mmap_sem);
Greg Ungerer72613e5f2007-02-07 12:03:08 +1000599 textpos = do_mmap(0, 0, len,
600 PROT_READ | PROT_EXEC | PROT_WRITE, MAP_PRIVATE, 0);
601 /* Remap to use all availabe slack region space */
602 if (textpos && (textpos < (unsigned long) -4096)) {
Pekka Enbergd100d142008-06-05 22:46:46 -0700603 reallen = kobjsize((void *)textpos);
Greg Ungerer72613e5f2007-02-07 12:03:08 +1000604 if (reallen > len) {
605 textpos = do_mremap(textpos, len, reallen,
606 MREMAP_FIXED, textpos);
607 }
608 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700609 up_write(&current->mm->mmap_sem);
Greg Ungerer72613e5f2007-02-07 12:03:08 +1000610
Linus Torvalds1da177e2005-04-16 15:20:36 -0700611 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);
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800616 ret = textpos;
Andrew Mortondf889122006-05-20 15:00:01 -0700617 goto err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700618 }
619
620 realdatastart = textpos + ntohl(hdr->data_start);
621 datapos = realdatastart + MAX_SHARED_LIBS * sizeof(unsigned long);
622 reloc = (unsigned long *) (textpos + ntohl(hdr->reloc_start) +
623 MAX_SHARED_LIBS * sizeof(unsigned long));
624 memp = textpos;
625
626#ifdef CONFIG_BINFMT_ZFLAT
627 /*
628 * load it all in and treat it like a RAM load from now on
629 */
630 if (flags & FLAT_FLAG_GZIP) {
631 result = decompress_exec(bprm, sizeof (struct flat_hdr),
632 (((char *) textpos) + sizeof (struct flat_hdr)),
633 (text_len + data_len + (relocs * sizeof(unsigned long))
634 - sizeof (struct flat_hdr)),
635 0);
636 memmove((void *) datapos, (void *) realdatastart,
637 data_len + (relocs * sizeof(unsigned long)));
638 } else if (flags & FLAT_FLAG_GZDATA) {
639 fpos = 0;
640 result = bprm->file->f_op->read(bprm->file,
641 (char *) textpos, text_len, &fpos);
642 if (result < (unsigned long) -4096)
643 result = decompress_exec(bprm, text_len, (char *) datapos,
644 data_len + (relocs * sizeof(unsigned long)), 0);
645 }
646 else
647#endif
648 {
649 fpos = 0;
650 result = bprm->file->f_op->read(bprm->file,
651 (char *) textpos, text_len, &fpos);
652 if (result < (unsigned long) -4096) {
653 fpos = ntohl(hdr->data_start);
654 result = bprm->file->f_op->read(bprm->file, (char *) datapos,
655 data_len + (relocs * sizeof(unsigned long)), &fpos);
656 }
657 }
658 if (result >= (unsigned long)-4096) {
659 printk("Unable to read code+data+bss, errno %d\n",(int)-result);
660 do_munmap(current->mm, textpos, text_len + data_len + extra +
661 MAX_SHARED_LIBS * sizeof(unsigned long));
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800662 ret = result;
Andrew Mortondf889122006-05-20 15:00:01 -0700663 goto err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700664 }
665 }
666
667 if (flags & FLAT_FLAG_KTRACE)
668 printk("Mapping is %x, Entry point is %x, data_start is %x\n",
669 (int)textpos, 0x00ffffff&ntohl(hdr->entry), ntohl(hdr->data_start));
670
671 /* The main program needs a little extra setup in the task structure */
672 start_code = textpos + sizeof (struct flat_hdr);
673 end_code = textpos + text_len;
674 if (id == 0) {
675 current->mm->start_code = start_code;
676 current->mm->end_code = end_code;
677 current->mm->start_data = datapos;
678 current->mm->end_data = datapos + data_len;
679 /*
680 * set up the brk stuff, uses any slack left in data/bss/stack
681 * allocation. We put the brk after the bss (between the bss
682 * and stack) like other platforms.
683 */
684 current->mm->start_brk = datapos + data_len + bss_len;
685 current->mm->brk = (current->mm->start_brk + 3) & ~3;
Pekka Enbergd100d142008-06-05 22:46:46 -0700686 current->mm->context.end_brk = memp + kobjsize((void *) memp) - stack_len;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700687 }
688
689 if (flags & FLAT_FLAG_KTRACE)
690 printk("%s %s: TEXT=%x-%x DATA=%x-%x BSS=%x-%x\n",
691 id ? "Lib" : "Load", bprm->filename,
692 (int) start_code, (int) end_code,
693 (int) datapos,
694 (int) (datapos + data_len),
695 (int) (datapos + data_len),
696 (int) (((datapos + data_len + bss_len) + 3) & ~3));
697
698 text_len -= sizeof(struct flat_hdr); /* the real code len */
699
700 /* Store the current module values into the global library structure */
701 libinfo->lib_list[id].start_code = start_code;
702 libinfo->lib_list[id].start_data = datapos;
703 libinfo->lib_list[id].start_brk = datapos + data_len + bss_len;
704 libinfo->lib_list[id].text_len = text_len;
705 libinfo->lib_list[id].loaded = 1;
706 libinfo->lib_list[id].entry = (0x00ffffff & ntohl(hdr->entry)) + textpos;
707 libinfo->lib_list[id].build_date = ntohl(hdr->build_date);
708
709 /*
710 * We just load the allocations into some temporary memory to
711 * help simplify all this mumbo jumbo
712 *
713 * We've got two different sections of relocation entries.
714 * The first is the GOT which resides at the begining of the data segment
715 * and is terminated with a -1. This one can be relocated in place.
716 * The second is the extra relocation entries tacked after the image's
717 * data segment. These require a little more processing as the entry is
718 * really an offset into the image which contains an offset into the
719 * image.
720 */
721 if (flags & FLAT_FLAG_GOTPIC) {
722 for (rp = (unsigned long *)datapos; *rp != 0xffffffff; rp++) {
723 unsigned long addr;
724 if (*rp) {
725 addr = calc_reloc(*rp, libinfo, id, 0);
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800726 if (addr == RELOC_FAILED) {
727 ret = -ENOEXEC;
Andrew Mortondf889122006-05-20 15:00:01 -0700728 goto err;
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800729 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700730 *rp = addr;
731 }
732 }
733 }
734
735 /*
736 * Now run through the relocation entries.
737 * We've got to be careful here as C++ produces relocatable zero
738 * entries in the constructor and destructor tables which are then
739 * tested for being not zero (which will always occur unless we're
740 * based from address zero). This causes an endless loop as __start
741 * is at zero. The solution used is to not relocate zero addresses.
742 * This has the negative side effect of not allowing a global data
743 * reference to be statically initialised to _stext (I've moved
744 * __start to address 4 so that is okay).
745 */
746 if (rev > OLD_FLAT_VERSION) {
Bernd Schmidtf9720202007-10-03 23:41:43 +0800747 unsigned long persistent = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700748 for (i=0; i < relocs; i++) {
749 unsigned long addr, relval;
750
751 /* Get the address of the pointer to be
752 relocated (of course, the address has to be
753 relocated first). */
754 relval = ntohl(reloc[i]);
Bernd Schmidtf9720202007-10-03 23:41:43 +0800755 if (flat_set_persistent (relval, &persistent))
756 continue;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700757 addr = flat_get_relocate_addr(relval);
758 rp = (unsigned long *) calc_reloc(addr, libinfo, id, 1);
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800759 if (rp == (unsigned long *)RELOC_FAILED) {
760 ret = -ENOEXEC;
Andrew Mortondf889122006-05-20 15:00:01 -0700761 goto err;
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800762 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700763
764 /* Get the pointer's value. */
Andrew Morton576bb9c2007-10-03 23:43:57 +0800765 addr = flat_get_addr_from_rp(rp, relval, flags,
766 &persistent);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700767 if (addr != 0) {
768 /*
769 * Do the relocation. PIC relocs in the data section are
770 * already in target order
771 */
772 if ((flags & FLAT_FLAG_GOTPIC) == 0)
773 addr = ntohl(addr);
774 addr = calc_reloc(addr, libinfo, id, 0);
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800775 if (addr == RELOC_FAILED) {
776 ret = -ENOEXEC;
Andrew Mortondf889122006-05-20 15:00:01 -0700777 goto err;
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800778 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700779
780 /* Write back the relocated pointer. */
781 flat_put_addr_at_rp(rp, addr, relval);
782 }
783 }
784 } else {
785 for (i=0; i < relocs; i++)
786 old_reloc(ntohl(reloc[i]));
787 }
788
789 flush_icache_range(start_code, end_code);
790
791 /* zero the BSS, BRK and stack areas */
792 memset((void*)(datapos + data_len), 0, bss_len +
Pekka Enbergd100d142008-06-05 22:46:46 -0700793 (memp + kobjsize((void *) memp) - stack_len - /* end brk */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700794 libinfo->lib_list[id].start_brk) + /* start brk */
795 stack_len);
796
797 return 0;
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800798err:
799 return ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700800}
801
802
803/****************************************************************************/
804#ifdef CONFIG_BINFMT_SHARED_FLAT
805
806/*
807 * Load a shared library into memory. The library gets its own data
808 * segment (including bss) but not argv/argc/environ.
809 */
810
811static int load_flat_shared_library(int id, struct lib_info *libs)
812{
813 struct linux_binprm bprm;
814 int res;
815 char buf[16];
816
817 /* Create the file name */
818 sprintf(buf, "/lib/lib%d.so", id);
819
820 /* Open the file up */
821 bprm.filename = buf;
822 bprm.file = open_exec(bprm.filename);
823 res = PTR_ERR(bprm.file);
824 if (IS_ERR(bprm.file))
825 return res;
826
827 res = prepare_binprm(&bprm);
828
829 if (res <= (unsigned long)-4096)
830 res = load_flat_file(&bprm, libs, id, NULL);
831 if (bprm.file) {
832 allow_write_access(bprm.file);
833 fput(bprm.file);
834 bprm.file = NULL;
835 }
836 return(res);
837}
838
839#endif /* CONFIG_BINFMT_SHARED_FLAT */
840/****************************************************************************/
841
842/*
843 * These are the functions used to load flat style executables and shared
844 * libraries. There is no binary dependent code anywhere else.
845 */
846
847static int load_flat_binary(struct linux_binprm * bprm, struct pt_regs * regs)
848{
849 struct lib_info libinfo;
850 unsigned long p = bprm->p;
851 unsigned long stack_len;
852 unsigned long start_addr;
853 unsigned long *sp;
854 int res;
855 int i, j;
856
857 memset(&libinfo, 0, sizeof(libinfo));
858 /*
859 * We have to add the size of our arguments to our stack size
860 * otherwise it's too easy for users to create stack overflows
861 * by passing in a huge argument list. And yes, we have to be
862 * pedantic and include space for the argv/envp array as it may have
863 * a lot of entries.
864 */
865#define TOP_OF_ARGS (PAGE_SIZE * MAX_ARG_PAGES - sizeof(void *))
866 stack_len = TOP_OF_ARGS - bprm->p; /* the strings */
867 stack_len += (bprm->argc + 1) * sizeof(char *); /* the argv array */
868 stack_len += (bprm->envc + 1) * sizeof(char *); /* the envp array */
869
870
871 res = load_flat_file(bprm, &libinfo, 0, &stack_len);
872 if (res > (unsigned long)-4096)
873 return res;
874
875 /* Update data segment pointers for all libraries */
876 for (i=0; i<MAX_SHARED_LIBS; i++)
877 if (libinfo.lib_list[i].loaded)
878 for (j=0; j<MAX_SHARED_LIBS; j++)
879 (-(j+1))[(unsigned long *)(libinfo.lib_list[i].start_data)] =
880 (libinfo.lib_list[j].loaded)?
881 libinfo.lib_list[j].start_data:UNLOADED_LIB;
882
David Howellsa6f76f22008-11-14 10:39:24 +1100883 install_exec_creds(bprm);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700884 current->flags &= ~PF_FORKNOEXEC;
885
886 set_binfmt(&flat_format);
887
888 p = ((current->mm->context.end_brk + stack_len + 3) & ~3) - 4;
889 DBG_FLT("p=%x\n", (int)p);
890
891 /* copy the arg pages onto the stack, this could be more efficient :-) */
892 for (i = TOP_OF_ARGS - 1; i >= bprm->p; i--)
893 * (char *) --p =
894 ((char *) page_address(bprm->page[i/PAGE_SIZE]))[i % PAGE_SIZE];
895
896 sp = (unsigned long *) create_flat_tables(p, bprm);
897
898 /* Fake some return addresses to ensure the call chain will
899 * initialise library in order for us. We are required to call
900 * lib 1 first, then 2, ... and finally the main program (id 0).
901 */
902 start_addr = libinfo.lib_list[0].entry;
903
904#ifdef CONFIG_BINFMT_SHARED_FLAT
905 for (i = MAX_SHARED_LIBS-1; i>0; i--) {
906 if (libinfo.lib_list[i].loaded) {
907 /* Push previos first to call address */
908 --sp; put_user(start_addr, sp);
909 start_addr = libinfo.lib_list[i].entry;
910 }
911 }
912#endif
913
914 /* Stash our initial stack pointer into the mm structure */
915 current->mm->start_stack = (unsigned long )sp;
916
Takashi YOSHII74c27c42008-08-11 20:10:54 +0900917#ifdef FLAT_PLAT_INIT
918 FLAT_PLAT_INIT(regs);
919#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700920 DBG_FLT("start_thread(regs=0x%x, entry=0x%x, start_stack=0x%x)\n",
921 (int)regs, (int)start_addr, (int)current->mm->start_stack);
922
923 start_thread(regs, start_addr, current->mm->start_stack);
924
Linus Torvalds1da177e2005-04-16 15:20:36 -0700925 return 0;
926}
927
928/****************************************************************************/
929
930static int __init init_flat_binfmt(void)
931{
932 return register_binfmt(&flat_format);
933}
934
Linus Torvalds1da177e2005-04-16 15:20:36 -0700935/****************************************************************************/
936
937core_initcall(init_flat_binfmt);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700938
939/****************************************************************************/