blob: a2796651e75690eb8e8a875146be852bfb1d637b [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>
Oskar Schirmerc3dc5be2009-05-28 14:34:31 -070044#include <asm/page.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070045
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
Oskar Schirmerc3dc5be2009-05-28 14:34:31 -070058/*
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
Linus Torvalds1da177e2005-04-16 15:20:36 -070070#define RELOC_FAILED 0xff00ff01 /* Relocation incorrect somewhere */
71#define UNLOADED_LIB 0x7ff000ff /* Placeholder for unused library */
72
73struct 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
86static int load_flat_shared_library(int id, struct lib_info *p);
87#endif
88
89static int load_flat_binary(struct linux_binprm *, struct pt_regs * regs);
Neil Horman7dc0b222007-10-16 23:26:34 -070090static int flat_core_dump(long signr, struct pt_regs *regs, struct file *file, unsigned long limit);
Linus Torvalds1da177e2005-04-16 15:20:36 -070091
Linus Torvalds1da177e2005-04-16 15:20:36 -070092static 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
Neil Horman7dc0b222007-10-16 23:26:34 -0700105static int flat_core_dump(long signr, struct pt_regs *regs, struct file *file, unsigned long limit)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700106{
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
119static 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;
Andrew Morton0e647c02007-10-16 23:27:26 -0700128 char uninitialized_var(dummy);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700129
Oskar Schirmerc3dc5be2009-05-28 14:34:31 -0700130 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);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700135
Linus Torvalds1da177e2005-04-16 15:20:36 -0700136 if (flat_argvp_envp_on_stack()) {
Oskar Schirmerc3dc5be2009-05-28 14:34:31 -0700137 put_user((unsigned long) envp, sp + 2);
138 put_user((unsigned long) argv, sp + 1);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700139 }
140
Oskar Schirmerc3dc5be2009-05-28 14:34:31 -0700141 put_user(argc, sp);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700142 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
179static 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);
Volodymyr G. Lukiianykf4cfb182008-10-15 22:01:15 -0700243 if (unlikely(LBUFSIZE <= ret)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700244 DBG_FLT("binfmt_flat: buffer overflow (EXTRA)?\n");
245 goto out_free_buf;
246 }
247 }
248 if (buf[3] & ORIG_NAME) {
Volodymyr G. Lukiianykf4cfb182008-10-15 22:01:15 -0700249 while (ret < LBUFSIZE && buf[ret++] != 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700250 ;
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) {
Volodymyr G. Lukiianykf4cfb182008-10-15 22:01:15 -0700257 while (ret < LBUFSIZE && buf[ret++] != 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700258 ;
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;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700281 len -= ret;
282
283 strm.next_in = buf;
284 strm.avail_in = ret;
285 strm.total_in = 0;
286 }
287
288 if (ret < 0) {
289 DBG_FLT("binfmt_flat: decompression failed (%d), %s\n",
290 ret, strm.msg);
291 goto out_zlib;
292 }
293
294 retval = 0;
295out_zlib:
296 zlib_inflateEnd(&strm);
297out_free_buf:
298 kfree(buf);
299out_free:
300 kfree(strm.workspace);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700301 return retval;
302}
303
304#endif /* CONFIG_BINFMT_ZFLAT */
305
306/****************************************************************************/
307
308static unsigned long
309calc_reloc(unsigned long r, struct lib_info *p, int curid, int internalp)
310{
311 unsigned long addr;
312 int id;
313 unsigned long start_brk;
314 unsigned long start_data;
315 unsigned long text_len;
316 unsigned long start_code;
317
318#ifdef CONFIG_BINFMT_SHARED_FLAT
319 if (r == 0)
320 id = curid; /* Relocs of 0 are always self referring */
321 else {
322 id = (r >> 24) & 0xff; /* Find ID for this reloc */
323 r &= 0x00ffffff; /* Trim ID off here */
324 }
325 if (id >= MAX_SHARED_LIBS) {
326 printk("BINFMT_FLAT: reference 0x%x to shared library %d",
327 (unsigned) r, id);
328 goto failed;
329 }
330 if (curid != id) {
331 if (internalp) {
332 printk("BINFMT_FLAT: reloc address 0x%x not in same module "
333 "(%d != %d)", (unsigned) r, curid, id);
334 goto failed;
335 } else if ( ! p->lib_list[id].loaded &&
Mike Frysinger0b8c78f2009-09-23 15:57:07 -0700336 IS_ERR_VALUE(load_flat_shared_library(id, p))) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700337 printk("BINFMT_FLAT: failed to load library %d", id);
338 goto failed;
339 }
340 /* Check versioning information (i.e. time stamps) */
341 if (p->lib_list[id].build_date && p->lib_list[curid].build_date &&
342 p->lib_list[curid].build_date < p->lib_list[id].build_date) {
343 printk("BINFMT_FLAT: library %d is younger than %d", id, curid);
344 goto failed;
345 }
346 }
347#else
348 id = 0;
349#endif
350
351 start_brk = p->lib_list[id].start_brk;
352 start_data = p->lib_list[id].start_data;
353 start_code = p->lib_list[id].start_code;
354 text_len = p->lib_list[id].text_len;
355
356 if (!flat_reloc_valid(r, start_brk - start_data + text_len)) {
357 printk("BINFMT_FLAT: reloc outside program 0x%x (0 - 0x%x/0x%x)",
358 (int) r,(int)(start_brk-start_code),(int)text_len);
359 goto failed;
360 }
361
362 if (r < text_len) /* In text segment */
363 addr = r + start_code;
364 else /* In data segment */
365 addr = r - text_len + start_data;
366
367 /* Range checked already above so doing the range tests is redundant...*/
368 return(addr);
369
370failed:
371 printk(", killing %s!\n", current->comm);
372 send_sig(SIGSEGV, current, 0);
373
374 return RELOC_FAILED;
375}
376
377/****************************************************************************/
378
379void old_reloc(unsigned long rl)
380{
381#ifdef DEBUG
382 char *segment[] = { "TEXT", "DATA", "BSS", "*UNKNOWN*" };
383#endif
384 flat_v2_reloc_t r;
385 unsigned long *ptr;
386
387 r.value = rl;
388#if defined(CONFIG_COLDFIRE)
389 ptr = (unsigned long *) (current->mm->start_code + r.reloc.offset);
390#else
391 ptr = (unsigned long *) (current->mm->start_data + r.reloc.offset);
392#endif
393
394#ifdef DEBUG
395 printk("Relocation of variable at DATASEG+%x "
396 "(address %p, currently %x) into segment %s\n",
397 r.reloc.offset, ptr, (int)*ptr, segment[r.reloc.type]);
398#endif
399
400 switch (r.reloc.type) {
401 case OLD_FLAT_RELOC_TYPE_TEXT:
402 *ptr += current->mm->start_code;
403 break;
404 case OLD_FLAT_RELOC_TYPE_DATA:
405 *ptr += current->mm->start_data;
406 break;
407 case OLD_FLAT_RELOC_TYPE_BSS:
408 *ptr += current->mm->end_data;
409 break;
410 default:
411 printk("BINFMT_FLAT: Unknown relocation type=%x\n", r.reloc.type);
412 break;
413 }
414
415#ifdef DEBUG
416 printk("Relocation became %x\n", (int)*ptr);
417#endif
418}
419
420/****************************************************************************/
421
422static int load_flat_file(struct linux_binprm * bprm,
423 struct lib_info *libinfo, int id, unsigned long *extra_stack)
424{
425 struct flat_hdr * hdr;
426 unsigned long textpos = 0, datapos = 0, result;
427 unsigned long realdatastart = 0;
428 unsigned long text_len, data_len, bss_len, stack_len, flags;
David Howells0f3e4422009-01-08 12:04:47 +0000429 unsigned long len, memp = 0;
430 unsigned long memp_size, extra, rlim;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700431 unsigned long *reloc = 0, *rp;
432 struct inode *inode;
433 int i, rev, relocs = 0;
434 loff_t fpos;
435 unsigned long start_code, end_code;
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800436 int ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700437
438 hdr = ((struct flat_hdr *) bprm->buf); /* exec-header */
Josef "Jeff" Sipek0f7fc9e42006-12-08 02:36:35 -0800439 inode = bprm->file->f_path.dentry->d_inode;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700440
441 text_len = ntohl(hdr->data_start);
442 data_len = ntohl(hdr->data_end) - ntohl(hdr->data_start);
443 bss_len = ntohl(hdr->bss_end) - ntohl(hdr->data_end);
444 stack_len = ntohl(hdr->stack_size);
445 if (extra_stack) {
446 stack_len += *extra_stack;
447 *extra_stack = stack_len;
448 }
449 relocs = ntohl(hdr->reloc_count);
450 flags = ntohl(hdr->flags);
451 rev = ntohl(hdr->rev);
452
Greg Ungerer845884d2006-01-10 16:59:37 +1000453 if (strncmp(hdr->magic, "bFLT", 4)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700454 /*
Mike Frysingere2a366d2008-02-14 19:31:29 -0800455 * Previously, here was a printk to tell people
456 * "BINFMT_FLAT: bad header magic".
457 * But for the kernel which also use ELF FD-PIC format, this
458 * error message is confusing.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700459 * because a lot of people do not manage to produce good
Linus Torvalds1da177e2005-04-16 15:20:36 -0700460 */
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800461 ret = -ENOEXEC;
462 goto err;
Greg Ungerer845884d2006-01-10 16:59:37 +1000463 }
464
465 if (flags & FLAT_FLAG_KTRACE)
466 printk("BINFMT_FLAT: Loading file: %s\n", bprm->filename);
467
468 if (rev != FLAT_VERSION && rev != OLD_FLAT_VERSION) {
Andrew Morton0e647c02007-10-16 23:27:26 -0700469 printk("BINFMT_FLAT: bad flat file version 0x%x (supported "
470 "0x%lx and 0x%lx)\n",
471 rev, FLAT_VERSION, OLD_FLAT_VERSION);
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800472 ret = -ENOEXEC;
473 goto err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700474 }
475
476 /* Don't allow old format executables to use shared libraries */
477 if (rev == OLD_FLAT_VERSION && id != 0) {
478 printk("BINFMT_FLAT: shared libraries are not available before rev 0x%x\n",
479 (int) FLAT_VERSION);
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800480 ret = -ENOEXEC;
481 goto err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700482 }
483
484 /*
485 * fix up the flags for the older format, there were all kinds
486 * of endian hacks, this only works for the simple cases
487 */
488 if (rev == OLD_FLAT_VERSION && flat_old_ram_flag(flags))
489 flags = FLAT_FLAG_RAM;
490
491#ifndef CONFIG_BINFMT_ZFLAT
492 if (flags & (FLAT_FLAG_GZIP|FLAT_FLAG_GZDATA)) {
493 printk("Support for ZFLAT executables is not enabled.\n");
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800494 ret = -ENOEXEC;
495 goto err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700496 }
497#endif
498
499 /*
500 * Check initial limits. This avoids letting people circumvent
501 * size limits imposed on them by creating programs with large
502 * arrays in the data or bss.
503 */
504 rlim = current->signal->rlim[RLIMIT_DATA].rlim_cur;
505 if (rlim >= RLIM_INFINITY)
506 rlim = ~0;
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800507 if (data_len + bss_len > rlim) {
508 ret = -ENOMEM;
509 goto err;
510 }
511
Linus Torvalds1da177e2005-04-16 15:20:36 -0700512 /* Flush all traces of the currently running executable */
513 if (id == 0) {
514 result = flush_old_exec(bprm);
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800515 if (result) {
516 ret = result;
Andrew Mortondf889122006-05-20 15:00:01 -0700517 goto err;
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800518 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700519
520 /* OK, This is the point of no return */
Malcolm Parsonsfcc18e82006-06-26 11:49:41 +1000521 set_personality(PER_LINUX_32BIT);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700522 }
523
524 /*
525 * calculate the extra space we need to map in
526 */
Andrew Morton0e647c02007-10-16 23:27:26 -0700527 extra = max_t(unsigned long, bss_len + stack_len,
528 relocs * sizeof(unsigned long));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700529
530 /*
531 * there are a couple of cases here, the separate code/data
532 * case, and then the fully copied to RAM case which lumps
533 * it all together.
534 */
535 if ((flags & (FLAT_FLAG_RAM|FLAT_FLAG_GZIP)) == 0) {
536 /*
537 * this should give us a ROM ptr, but if it doesn't we don't
538 * really care
539 */
540 DBG_FLT("BINFMT_FLAT: ROM mapping of file (we hope)\n");
541
542 down_write(&current->mm->mmap_sem);
Matt Helsley925d1c42008-04-29 01:01:36 -0700543 textpos = do_mmap(bprm->file, 0, text_len, PROT_READ|PROT_EXEC,
544 MAP_PRIVATE|MAP_EXECUTABLE, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700545 up_write(&current->mm->mmap_sem);
Mike Frysinger0b8c78f2009-09-23 15:57:07 -0700546 if (!textpos || IS_ERR_VALUE(textpos)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700547 if (!textpos)
548 textpos = (unsigned long) -ENOMEM;
549 printk("Unable to mmap process text, errno %d\n", (int)-textpos);
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800550 ret = textpos;
Andrew Mortondf889122006-05-20 15:00:01 -0700551 goto err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700552 }
553
Greg Ungerer72613e5f2007-02-07 12:03:08 +1000554 len = data_len + extra + MAX_SHARED_LIBS * sizeof(unsigned long);
David Howells0f3e4422009-01-08 12:04:47 +0000555 len = PAGE_ALIGN(len);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700556 down_write(&current->mm->mmap_sem);
Greg Ungerer72613e5f2007-02-07 12:03:08 +1000557 realdatastart = do_mmap(0, 0, len,
558 PROT_READ|PROT_WRITE|PROT_EXEC, MAP_PRIVATE, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700559 up_write(&current->mm->mmap_sem);
560
Mike Frysinger0b8c78f2009-09-23 15:57:07 -0700561 if (realdatastart == 0 || IS_ERR_VALUE(realdatastart)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700562 if (!realdatastart)
563 realdatastart = (unsigned long) -ENOMEM;
564 printk("Unable to allocate RAM for process data, errno %d\n",
Greg Ungererc287ef12007-06-08 13:46:43 -0700565 (int)-realdatastart);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700566 do_munmap(current->mm, textpos, text_len);
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800567 ret = realdatastart;
Andrew Mortondf889122006-05-20 15:00:01 -0700568 goto err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700569 }
Oskar Schirmerc3dc5be2009-05-28 14:34:31 -0700570 datapos = ALIGN(realdatastart +
571 MAX_SHARED_LIBS * sizeof(unsigned long),
572 FLAT_DATA_ALIGN);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700573
574 DBG_FLT("BINFMT_FLAT: Allocated data+bss+stack (%d bytes): %x\n",
575 (int)(data_len + bss_len + stack_len), (int)datapos);
576
577 fpos = ntohl(hdr->data_start);
578#ifdef CONFIG_BINFMT_ZFLAT
579 if (flags & FLAT_FLAG_GZDATA) {
580 result = decompress_exec(bprm, fpos, (char *) datapos,
581 data_len + (relocs * sizeof(unsigned long)), 0);
582 } else
583#endif
584 {
585 result = bprm->file->f_op->read(bprm->file, (char *) datapos,
586 data_len + (relocs * sizeof(unsigned long)), &fpos);
587 }
Mike Frysinger0b8c78f2009-09-23 15:57:07 -0700588 if (IS_ERR_VALUE(result)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700589 printk("Unable to read data+bss, errno %d\n", (int)-result);
590 do_munmap(current->mm, textpos, text_len);
591 do_munmap(current->mm, realdatastart, data_len + extra);
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800592 ret = result;
Andrew Mortondf889122006-05-20 15:00:01 -0700593 goto err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700594 }
595
596 reloc = (unsigned long *) (datapos+(ntohl(hdr->reloc_start)-text_len));
597 memp = realdatastart;
David Howells0f3e4422009-01-08 12:04:47 +0000598 memp_size = len;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700599 } else {
600
Greg Ungerer72613e5f2007-02-07 12:03:08 +1000601 len = text_len + data_len + extra + MAX_SHARED_LIBS * sizeof(unsigned long);
David Howells0f3e4422009-01-08 12:04:47 +0000602 len = PAGE_ALIGN(len);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700603 down_write(&current->mm->mmap_sem);
Greg Ungerer72613e5f2007-02-07 12:03:08 +1000604 textpos = do_mmap(0, 0, len,
605 PROT_READ | PROT_EXEC | PROT_WRITE, MAP_PRIVATE, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700606 up_write(&current->mm->mmap_sem);
Greg Ungerer72613e5f2007-02-07 12:03:08 +1000607
Mike Frysinger0b8c78f2009-09-23 15:57:07 -0700608 if (!textpos || IS_ERR_VALUE(textpos)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700609 if (!textpos)
610 textpos = (unsigned long) -ENOMEM;
611 printk("Unable to allocate RAM for process text/data, errno %d\n",
612 (int)-textpos);
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800613 ret = textpos;
Andrew Mortondf889122006-05-20 15:00:01 -0700614 goto err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700615 }
616
617 realdatastart = textpos + ntohl(hdr->data_start);
Oskar Schirmerc3dc5be2009-05-28 14:34:31 -0700618 datapos = ALIGN(realdatastart +
619 MAX_SHARED_LIBS * sizeof(unsigned long),
620 FLAT_DATA_ALIGN);
621
622 reloc = (unsigned long *)
623 (datapos + (ntohl(hdr->reloc_start) - text_len));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700624 memp = textpos;
David Howells0f3e4422009-01-08 12:04:47 +0000625 memp_size = len;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700626#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);
Mike Frysinger0b8c78f2009-09-23 15:57:07 -0700642 if (!IS_ERR_VALUE(result))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700643 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);
Mike Frysinger0b8c78f2009-09-23 15:57:07 -0700652 if (!IS_ERR_VALUE(result)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700653 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 }
Mike Frysinger0b8c78f2009-09-23 15:57:07 -0700658 if (IS_ERR_VALUE(result)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700659 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.
David Howells0f3e4422009-01-08 12:04:47 +0000683 * Userspace code relies on the stack pointer starting out at
684 * an address right at the end of a page.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700685 */
686 current->mm->start_brk = datapos + data_len + bss_len;
687 current->mm->brk = (current->mm->start_brk + 3) & ~3;
David Howells0f3e4422009-01-08 12:04:47 +0000688 current->mm->context.end_brk = memp + memp_size - stack_len;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700689 }
690
691 if (flags & FLAT_FLAG_KTRACE)
692 printk("%s %s: TEXT=%x-%x DATA=%x-%x BSS=%x-%x\n",
693 id ? "Lib" : "Load", bprm->filename,
694 (int) start_code, (int) end_code,
695 (int) datapos,
696 (int) (datapos + data_len),
697 (int) (datapos + data_len),
698 (int) (((datapos + data_len + bss_len) + 3) & ~3));
699
700 text_len -= sizeof(struct flat_hdr); /* the real code len */
701
702 /* Store the current module values into the global library structure */
703 libinfo->lib_list[id].start_code = start_code;
704 libinfo->lib_list[id].start_data = datapos;
705 libinfo->lib_list[id].start_brk = datapos + data_len + bss_len;
706 libinfo->lib_list[id].text_len = text_len;
707 libinfo->lib_list[id].loaded = 1;
708 libinfo->lib_list[id].entry = (0x00ffffff & ntohl(hdr->entry)) + textpos;
709 libinfo->lib_list[id].build_date = ntohl(hdr->build_date);
710
711 /*
712 * We just load the allocations into some temporary memory to
713 * help simplify all this mumbo jumbo
714 *
715 * We've got two different sections of relocation entries.
716 * The first is the GOT which resides at the begining of the data segment
717 * and is terminated with a -1. This one can be relocated in place.
718 * The second is the extra relocation entries tacked after the image's
719 * data segment. These require a little more processing as the entry is
720 * really an offset into the image which contains an offset into the
721 * image.
722 */
723 if (flags & FLAT_FLAG_GOTPIC) {
724 for (rp = (unsigned long *)datapos; *rp != 0xffffffff; rp++) {
725 unsigned long addr;
726 if (*rp) {
727 addr = calc_reloc(*rp, libinfo, id, 0);
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800728 if (addr == RELOC_FAILED) {
729 ret = -ENOEXEC;
Andrew Mortondf889122006-05-20 15:00:01 -0700730 goto err;
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800731 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700732 *rp = addr;
733 }
734 }
735 }
736
737 /*
738 * Now run through the relocation entries.
739 * We've got to be careful here as C++ produces relocatable zero
740 * entries in the constructor and destructor tables which are then
741 * tested for being not zero (which will always occur unless we're
742 * based from address zero). This causes an endless loop as __start
743 * is at zero. The solution used is to not relocate zero addresses.
744 * This has the negative side effect of not allowing a global data
745 * reference to be statically initialised to _stext (I've moved
746 * __start to address 4 so that is okay).
747 */
748 if (rev > OLD_FLAT_VERSION) {
Bernd Schmidtf9720202007-10-03 23:41:43 +0800749 unsigned long persistent = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700750 for (i=0; i < relocs; i++) {
751 unsigned long addr, relval;
752
753 /* Get the address of the pointer to be
754 relocated (of course, the address has to be
755 relocated first). */
756 relval = ntohl(reloc[i]);
Bernd Schmidtf9720202007-10-03 23:41:43 +0800757 if (flat_set_persistent (relval, &persistent))
758 continue;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700759 addr = flat_get_relocate_addr(relval);
760 rp = (unsigned long *) calc_reloc(addr, libinfo, id, 1);
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800761 if (rp == (unsigned long *)RELOC_FAILED) {
762 ret = -ENOEXEC;
Andrew Mortondf889122006-05-20 15:00:01 -0700763 goto err;
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800764 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700765
766 /* Get the pointer's value. */
Andrew Morton576bb9c2007-10-03 23:43:57 +0800767 addr = flat_get_addr_from_rp(rp, relval, flags,
768 &persistent);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700769 if (addr != 0) {
770 /*
771 * Do the relocation. PIC relocs in the data section are
772 * already in target order
773 */
774 if ((flags & FLAT_FLAG_GOTPIC) == 0)
775 addr = ntohl(addr);
776 addr = calc_reloc(addr, libinfo, id, 0);
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800777 if (addr == RELOC_FAILED) {
778 ret = -ENOEXEC;
Andrew Mortondf889122006-05-20 15:00:01 -0700779 goto err;
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800780 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700781
782 /* Write back the relocated pointer. */
783 flat_put_addr_at_rp(rp, addr, relval);
784 }
785 }
786 } else {
787 for (i=0; i < relocs; i++)
788 old_reloc(ntohl(reloc[i]));
789 }
790
791 flush_icache_range(start_code, end_code);
792
793 /* zero the BSS, BRK and stack areas */
794 memset((void*)(datapos + data_len), 0, bss_len +
David Howells0f3e4422009-01-08 12:04:47 +0000795 (memp + memp_size - stack_len - /* end brk */
796 libinfo->lib_list[id].start_brk) + /* start brk */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700797 stack_len);
798
799 return 0;
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800800err:
801 return ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700802}
803
804
805/****************************************************************************/
806#ifdef CONFIG_BINFMT_SHARED_FLAT
807
808/*
809 * Load a shared library into memory. The library gets its own data
810 * segment (including bss) but not argv/argc/environ.
811 */
812
813static int load_flat_shared_library(int id, struct lib_info *libs)
814{
815 struct linux_binprm bprm;
816 int res;
817 char buf[16];
818
819 /* Create the file name */
820 sprintf(buf, "/lib/lib%d.so", id);
821
822 /* Open the file up */
823 bprm.filename = buf;
824 bprm.file = open_exec(bprm.filename);
825 res = PTR_ERR(bprm.file);
826 if (IS_ERR(bprm.file))
827 return res;
828
Linus Torvalds34406252009-08-06 15:09:34 -0700829 bprm.cred = prepare_exec_creds();
830 res = -ENOMEM;
831 if (!bprm.cred)
832 goto out;
833
Linus Torvalds1da177e2005-04-16 15:20:36 -0700834 res = prepare_binprm(&bprm);
835
Mike Frysinger0b8c78f2009-09-23 15:57:07 -0700836 if (!IS_ERR_VALUE(res))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700837 res = load_flat_file(&bprm, libs, id, NULL);
Linus Torvalds34406252009-08-06 15:09:34 -0700838
839 abort_creds(bprm.cred);
840
841out:
842 allow_write_access(bprm.file);
843 fput(bprm.file);
844
Linus Torvalds1da177e2005-04-16 15:20:36 -0700845 return(res);
846}
847
848#endif /* CONFIG_BINFMT_SHARED_FLAT */
849/****************************************************************************/
850
851/*
852 * These are the functions used to load flat style executables and shared
853 * libraries. There is no binary dependent code anywhere else.
854 */
855
856static int load_flat_binary(struct linux_binprm * bprm, struct pt_regs * regs)
857{
858 struct lib_info libinfo;
859 unsigned long p = bprm->p;
860 unsigned long stack_len;
861 unsigned long start_addr;
862 unsigned long *sp;
863 int res;
864 int i, j;
865
866 memset(&libinfo, 0, sizeof(libinfo));
867 /*
868 * We have to add the size of our arguments to our stack size
869 * otherwise it's too easy for users to create stack overflows
870 * by passing in a huge argument list. And yes, we have to be
871 * pedantic and include space for the argv/envp array as it may have
872 * a lot of entries.
873 */
874#define TOP_OF_ARGS (PAGE_SIZE * MAX_ARG_PAGES - sizeof(void *))
875 stack_len = TOP_OF_ARGS - bprm->p; /* the strings */
876 stack_len += (bprm->argc + 1) * sizeof(char *); /* the argv array */
877 stack_len += (bprm->envc + 1) * sizeof(char *); /* the envp array */
Oskar Schirmerc3dc5be2009-05-28 14:34:31 -0700878 stack_len += FLAT_DATA_ALIGN - 1; /* reserve for upcoming alignment */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700879
880 res = load_flat_file(bprm, &libinfo, 0, &stack_len);
Mike Frysinger0b8c78f2009-09-23 15:57:07 -0700881 if (IS_ERR_VALUE(res))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700882 return res;
883
884 /* Update data segment pointers for all libraries */
885 for (i=0; i<MAX_SHARED_LIBS; i++)
886 if (libinfo.lib_list[i].loaded)
887 for (j=0; j<MAX_SHARED_LIBS; j++)
888 (-(j+1))[(unsigned long *)(libinfo.lib_list[i].start_data)] =
889 (libinfo.lib_list[j].loaded)?
890 libinfo.lib_list[j].start_data:UNLOADED_LIB;
891
David Howellsa6f76f22008-11-14 10:39:24 +1100892 install_exec_creds(bprm);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700893 current->flags &= ~PF_FORKNOEXEC;
894
895 set_binfmt(&flat_format);
896
897 p = ((current->mm->context.end_brk + stack_len + 3) & ~3) - 4;
898 DBG_FLT("p=%x\n", (int)p);
899
900 /* copy the arg pages onto the stack, this could be more efficient :-) */
901 for (i = TOP_OF_ARGS - 1; i >= bprm->p; i--)
902 * (char *) --p =
903 ((char *) page_address(bprm->page[i/PAGE_SIZE]))[i % PAGE_SIZE];
904
905 sp = (unsigned long *) create_flat_tables(p, bprm);
906
907 /* Fake some return addresses to ensure the call chain will
908 * initialise library in order for us. We are required to call
909 * lib 1 first, then 2, ... and finally the main program (id 0).
910 */
911 start_addr = libinfo.lib_list[0].entry;
912
913#ifdef CONFIG_BINFMT_SHARED_FLAT
914 for (i = MAX_SHARED_LIBS-1; i>0; i--) {
915 if (libinfo.lib_list[i].loaded) {
916 /* Push previos first to call address */
917 --sp; put_user(start_addr, sp);
918 start_addr = libinfo.lib_list[i].entry;
919 }
920 }
921#endif
922
923 /* Stash our initial stack pointer into the mm structure */
924 current->mm->start_stack = (unsigned long )sp;
925
Takashi YOSHII74c27c42008-08-11 20:10:54 +0900926#ifdef FLAT_PLAT_INIT
927 FLAT_PLAT_INIT(regs);
928#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700929 DBG_FLT("start_thread(regs=0x%x, entry=0x%x, start_stack=0x%x)\n",
930 (int)regs, (int)start_addr, (int)current->mm->start_stack);
931
932 start_thread(regs, start_addr, current->mm->start_stack);
933
Linus Torvalds1da177e2005-04-16 15:20:36 -0700934 return 0;
935}
936
937/****************************************************************************/
938
939static int __init init_flat_binfmt(void)
940{
941 return register_binfmt(&flat_format);
942}
943
Linus Torvalds1da177e2005-04-16 15:20:36 -0700944/****************************************************************************/
945
946core_initcall(init_flat_binfmt);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700947
948/****************************************************************************/