blob: e280352b28f9e48adab2cc8d94963b0cbaf8b181 [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
Paul Gortmaker630d9c42011-11-16 23:57:37 -050018#include <linux/export.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>
Linus Torvalds1da177e2005-04-16 15:20:36 -070040#include <asm/uaccess.h>
41#include <asm/unaligned.h>
42#include <asm/cacheflush.h>
Oskar Schirmerc3dc5be2009-05-28 14:34:31 -070043#include <asm/page.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070044
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
Oskar Schirmerc3dc5be2009-05-28 14:34:31 -070057/*
Mike Frysinger2e94de82010-06-04 14:14:53 -070058 * User data (data section and bss) needs to be aligned.
59 * We pick 0x20 here because it is the max value elf2flt has always
60 * used in producing FLAT files, and because it seems to be large
61 * enough to make all the gcc alignment related tests happy.
62 */
63#define FLAT_DATA_ALIGN (0x20)
64
65/*
66 * User data (stack) also needs to be aligned.
67 * Here we can be a bit looser than the data sections since this
68 * needs to only meet arch ABI requirements.
Oskar Schirmerc3dc5be2009-05-28 14:34:31 -070069 */
Mike Frysinger29520952010-06-29 15:05:21 -070070#define FLAT_STACK_ALIGN max_t(unsigned long, sizeof(void *), ARCH_SLAB_MINALIGN)
Oskar Schirmerc3dc5be2009-05-28 14:34:31 -070071
Linus Torvalds1da177e2005-04-16 15:20:36 -070072#define RELOC_FAILED 0xff00ff01 /* Relocation incorrect somewhere */
73#define UNLOADED_LIB 0x7ff000ff /* Placeholder for unused library */
74
75struct lib_info {
76 struct {
77 unsigned long start_code; /* Start of text segment */
78 unsigned long start_data; /* Start of data segment */
79 unsigned long start_brk; /* End of data segment */
80 unsigned long text_len; /* Length of text segment */
81 unsigned long entry; /* Start address for this module */
82 unsigned long build_date; /* When this one was compiled */
83 short loaded; /* Has this library been loaded? */
84 } lib_list[MAX_SHARED_LIBS];
85};
86
87#ifdef CONFIG_BINFMT_SHARED_FLAT
88static int load_flat_shared_library(int id, struct lib_info *p);
89#endif
90
91static int load_flat_binary(struct linux_binprm *, struct pt_regs * regs);
Masami Hiramatsuf6151df2009-12-17 15:27:16 -080092static int flat_core_dump(struct coredump_params *cprm);
Linus Torvalds1da177e2005-04-16 15:20:36 -070093
Linus Torvalds1da177e2005-04-16 15:20:36 -070094static struct linux_binfmt flat_format = {
95 .module = THIS_MODULE,
96 .load_binary = load_flat_binary,
97 .core_dump = flat_core_dump,
98 .min_coredump = PAGE_SIZE
99};
100
101/****************************************************************************/
102/*
103 * Routine writes a core dump image in the current directory.
104 * Currently only a stub-function.
105 */
106
Masami Hiramatsuf6151df2009-12-17 15:27:16 -0800107static int flat_core_dump(struct coredump_params *cprm)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700108{
109 printk("Process %s:%d received signr %d and should have core dumped\n",
Denys Vlasenko5ab1c302012-10-04 17:15:29 -0700110 current->comm, current->pid, (int) cprm->siginfo->si_signo);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700111 return(1);
112}
113
114/****************************************************************************/
115/*
116 * create_flat_tables() parses the env- and arg-strings in new user
117 * memory and creates the pointer tables from them, and puts their
118 * addresses on the "stack", returning the new stack pointer value.
119 */
120
121static unsigned long create_flat_tables(
122 unsigned long pp,
123 struct linux_binprm * bprm)
124{
125 unsigned long *argv,*envp;
126 unsigned long * sp;
127 char * p = (char*)pp;
128 int argc = bprm->argc;
129 int envc = bprm->envc;
Andrew Morton0e647c02007-10-16 23:27:26 -0700130 char uninitialized_var(dummy);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700131
Oskar Schirmerc3dc5be2009-05-28 14:34:31 -0700132 sp = (unsigned long *)p;
133 sp -= (envc + argc + 2) + 1 + (flat_argvp_envp_on_stack() ? 2 : 0);
Mike Frysinger2e94de82010-06-04 14:14:53 -0700134 sp = (unsigned long *) ((unsigned long)sp & -FLAT_STACK_ALIGN);
Oskar Schirmerc3dc5be2009-05-28 14:34:31 -0700135 argv = sp + 1 + (flat_argvp_envp_on_stack() ? 2 : 0);
136 envp = argv + (argc + 1);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700137
Linus Torvalds1da177e2005-04-16 15:20:36 -0700138 if (flat_argvp_envp_on_stack()) {
Oskar Schirmerc3dc5be2009-05-28 14:34:31 -0700139 put_user((unsigned long) envp, sp + 2);
140 put_user((unsigned long) argv, sp + 1);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700141 }
142
Oskar Schirmerc3dc5be2009-05-28 14:34:31 -0700143 put_user(argc, sp);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700144 current->mm->arg_start = (unsigned long) p;
145 while (argc-->0) {
146 put_user((unsigned long) p, argv++);
147 do {
148 get_user(dummy, p); p++;
149 } while (dummy);
150 }
151 put_user((unsigned long) NULL, argv);
152 current->mm->arg_end = current->mm->env_start = (unsigned long) p;
153 while (envc-->0) {
154 put_user((unsigned long)p, envp); envp++;
155 do {
156 get_user(dummy, p); p++;
157 } while (dummy);
158 }
159 put_user((unsigned long) NULL, envp);
160 current->mm->env_end = (unsigned long) p;
161 return (unsigned long)sp;
162}
163
164/****************************************************************************/
165
166#ifdef CONFIG_BINFMT_ZFLAT
167
168#include <linux/zlib.h>
169
170#define LBUFSIZE 4000
171
172/* gzip flag byte */
173#define ASCII_FLAG 0x01 /* bit 0 set: file probably ASCII text */
174#define CONTINUATION 0x02 /* bit 1 set: continuation of multi-part gzip file */
175#define EXTRA_FIELD 0x04 /* bit 2 set: extra field present */
176#define ORIG_NAME 0x08 /* bit 3 set: original file name present */
177#define COMMENT 0x10 /* bit 4 set: file comment present */
178#define ENCRYPTED 0x20 /* bit 5 set: file is encrypted */
179#define RESERVED 0xC0 /* bit 6,7: reserved */
180
181static int decompress_exec(
182 struct linux_binprm *bprm,
183 unsigned long offset,
184 char *dst,
185 long len,
186 int fd)
187{
188 unsigned char *buf;
189 z_stream strm;
190 loff_t fpos;
191 int ret, retval;
192
193 DBG_FLT("decompress_exec(offset=%x,buf=%x,len=%x)\n",(int)offset, (int)dst, (int)len);
194
195 memset(&strm, 0, sizeof(strm));
196 strm.workspace = kmalloc(zlib_inflate_workspacesize(), GFP_KERNEL);
197 if (strm.workspace == NULL) {
198 DBG_FLT("binfmt_flat: no memory for decompress workspace\n");
199 return -ENOMEM;
200 }
201 buf = kmalloc(LBUFSIZE, GFP_KERNEL);
202 if (buf == NULL) {
203 DBG_FLT("binfmt_flat: no memory for read buffer\n");
204 retval = -ENOMEM;
205 goto out_free;
206 }
207
208 /* Read in first chunk of data and parse gzip header. */
209 fpos = offset;
210 ret = bprm->file->f_op->read(bprm->file, buf, LBUFSIZE, &fpos);
211
212 strm.next_in = buf;
213 strm.avail_in = ret;
214 strm.total_in = 0;
215
216 retval = -ENOEXEC;
217
218 /* Check minimum size -- gzip header */
219 if (ret < 10) {
220 DBG_FLT("binfmt_flat: file too small?\n");
221 goto out_free_buf;
222 }
223
224 /* Check gzip magic number */
225 if ((buf[0] != 037) || ((buf[1] != 0213) && (buf[1] != 0236))) {
226 DBG_FLT("binfmt_flat: unknown compression magic?\n");
227 goto out_free_buf;
228 }
229
230 /* Check gzip method */
231 if (buf[2] != 8) {
232 DBG_FLT("binfmt_flat: unknown compression method?\n");
233 goto out_free_buf;
234 }
235 /* Check gzip flags */
236 if ((buf[3] & ENCRYPTED) || (buf[3] & CONTINUATION) ||
237 (buf[3] & RESERVED)) {
238 DBG_FLT("binfmt_flat: unknown flags?\n");
239 goto out_free_buf;
240 }
241
242 ret = 10;
243 if (buf[3] & EXTRA_FIELD) {
244 ret += 2 + buf[10] + (buf[11] << 8);
Volodymyr G. Lukiianykf4cfb182008-10-15 22:01:15 -0700245 if (unlikely(LBUFSIZE <= ret)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700246 DBG_FLT("binfmt_flat: buffer overflow (EXTRA)?\n");
247 goto out_free_buf;
248 }
249 }
250 if (buf[3] & ORIG_NAME) {
Volodymyr G. Lukiianykf4cfb182008-10-15 22:01:15 -0700251 while (ret < LBUFSIZE && buf[ret++] != 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700252 ;
253 if (unlikely(LBUFSIZE == ret)) {
254 DBG_FLT("binfmt_flat: buffer overflow (ORIG_NAME)?\n");
255 goto out_free_buf;
256 }
257 }
258 if (buf[3] & COMMENT) {
Volodymyr G. Lukiianykf4cfb182008-10-15 22:01:15 -0700259 while (ret < LBUFSIZE && buf[ret++] != 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700260 ;
261 if (unlikely(LBUFSIZE == ret)) {
262 DBG_FLT("binfmt_flat: buffer overflow (COMMENT)?\n");
263 goto out_free_buf;
264 }
265 }
266
267 strm.next_in += ret;
268 strm.avail_in -= ret;
269
270 strm.next_out = dst;
271 strm.avail_out = len;
272 strm.total_out = 0;
273
274 if (zlib_inflateInit2(&strm, -MAX_WBITS) != Z_OK) {
275 DBG_FLT("binfmt_flat: zlib init failed?\n");
276 goto out_free_buf;
277 }
278
279 while ((ret = zlib_inflate(&strm, Z_NO_FLUSH)) == Z_OK) {
280 ret = bprm->file->f_op->read(bprm->file, buf, LBUFSIZE, &fpos);
281 if (ret <= 0)
282 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700283 len -= ret;
284
285 strm.next_in = buf;
286 strm.avail_in = ret;
287 strm.total_in = 0;
288 }
289
290 if (ret < 0) {
291 DBG_FLT("binfmt_flat: decompression failed (%d), %s\n",
292 ret, strm.msg);
293 goto out_zlib;
294 }
295
296 retval = 0;
297out_zlib:
298 zlib_inflateEnd(&strm);
299out_free_buf:
300 kfree(buf);
301out_free:
302 kfree(strm.workspace);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700303 return retval;
304}
305
306#endif /* CONFIG_BINFMT_ZFLAT */
307
308/****************************************************************************/
309
310static unsigned long
311calc_reloc(unsigned long r, struct lib_info *p, int curid, int internalp)
312{
313 unsigned long addr;
314 int id;
315 unsigned long start_brk;
316 unsigned long start_data;
317 unsigned long text_len;
318 unsigned long start_code;
319
320#ifdef CONFIG_BINFMT_SHARED_FLAT
321 if (r == 0)
322 id = curid; /* Relocs of 0 are always self referring */
323 else {
324 id = (r >> 24) & 0xff; /* Find ID for this reloc */
325 r &= 0x00ffffff; /* Trim ID off here */
326 }
327 if (id >= MAX_SHARED_LIBS) {
328 printk("BINFMT_FLAT: reference 0x%x to shared library %d",
329 (unsigned) r, id);
330 goto failed;
331 }
332 if (curid != id) {
333 if (internalp) {
334 printk("BINFMT_FLAT: reloc address 0x%x not in same module "
335 "(%d != %d)", (unsigned) r, curid, id);
336 goto failed;
337 } else if ( ! p->lib_list[id].loaded &&
Mike Frysinger0b8c78f2009-09-23 15:57:07 -0700338 IS_ERR_VALUE(load_flat_shared_library(id, p))) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700339 printk("BINFMT_FLAT: failed to load library %d", id);
340 goto failed;
341 }
342 /* Check versioning information (i.e. time stamps) */
343 if (p->lib_list[id].build_date && p->lib_list[curid].build_date &&
344 p->lib_list[curid].build_date < p->lib_list[id].build_date) {
345 printk("BINFMT_FLAT: library %d is younger than %d", id, curid);
346 goto failed;
347 }
348 }
349#else
350 id = 0;
351#endif
352
353 start_brk = p->lib_list[id].start_brk;
354 start_data = p->lib_list[id].start_data;
355 start_code = p->lib_list[id].start_code;
356 text_len = p->lib_list[id].text_len;
357
358 if (!flat_reloc_valid(r, start_brk - start_data + text_len)) {
359 printk("BINFMT_FLAT: reloc outside program 0x%x (0 - 0x%x/0x%x)",
Jun Sund7dfee32009-12-31 17:28:52 -0800360 (int) r,(int)(start_brk-start_data+text_len),(int)text_len);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700361 goto failed;
362 }
363
364 if (r < text_len) /* In text segment */
365 addr = r + start_code;
366 else /* In data segment */
367 addr = r - text_len + start_data;
368
369 /* Range checked already above so doing the range tests is redundant...*/
370 return(addr);
371
372failed:
373 printk(", killing %s!\n", current->comm);
374 send_sig(SIGSEGV, current, 0);
375
376 return RELOC_FAILED;
377}
378
379/****************************************************************************/
380
381void old_reloc(unsigned long rl)
382{
383#ifdef DEBUG
384 char *segment[] = { "TEXT", "DATA", "BSS", "*UNKNOWN*" };
385#endif
386 flat_v2_reloc_t r;
387 unsigned long *ptr;
388
389 r.value = rl;
390#if defined(CONFIG_COLDFIRE)
391 ptr = (unsigned long *) (current->mm->start_code + r.reloc.offset);
392#else
393 ptr = (unsigned long *) (current->mm->start_data + r.reloc.offset);
394#endif
395
396#ifdef DEBUG
397 printk("Relocation of variable at DATASEG+%x "
398 "(address %p, currently %x) into segment %s\n",
399 r.reloc.offset, ptr, (int)*ptr, segment[r.reloc.type]);
400#endif
401
402 switch (r.reloc.type) {
403 case OLD_FLAT_RELOC_TYPE_TEXT:
404 *ptr += current->mm->start_code;
405 break;
406 case OLD_FLAT_RELOC_TYPE_DATA:
407 *ptr += current->mm->start_data;
408 break;
409 case OLD_FLAT_RELOC_TYPE_BSS:
410 *ptr += current->mm->end_data;
411 break;
412 default:
413 printk("BINFMT_FLAT: Unknown relocation type=%x\n", r.reloc.type);
414 break;
415 }
416
417#ifdef DEBUG
418 printk("Relocation became %x\n", (int)*ptr);
419#endif
420}
421
422/****************************************************************************/
423
424static int load_flat_file(struct linux_binprm * bprm,
425 struct lib_info *libinfo, int id, unsigned long *extra_stack)
426{
427 struct flat_hdr * hdr;
428 unsigned long textpos = 0, datapos = 0, result;
429 unsigned long realdatastart = 0;
430 unsigned long text_len, data_len, bss_len, stack_len, flags;
David Howells0f3e4422009-01-08 12:04:47 +0000431 unsigned long len, memp = 0;
432 unsigned long memp_size, extra, rlim;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700433 unsigned long *reloc = 0, *rp;
434 struct inode *inode;
435 int i, rev, relocs = 0;
436 loff_t fpos;
437 unsigned long start_code, end_code;
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800438 int ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700439
440 hdr = ((struct flat_hdr *) bprm->buf); /* exec-header */
Josef "Jeff" Sipek0f7fc9e2006-12-08 02:36:35 -0800441 inode = bprm->file->f_path.dentry->d_inode;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700442
443 text_len = ntohl(hdr->data_start);
444 data_len = ntohl(hdr->data_end) - ntohl(hdr->data_start);
445 bss_len = ntohl(hdr->bss_end) - ntohl(hdr->data_end);
446 stack_len = ntohl(hdr->stack_size);
447 if (extra_stack) {
448 stack_len += *extra_stack;
449 *extra_stack = stack_len;
450 }
451 relocs = ntohl(hdr->reloc_count);
452 flags = ntohl(hdr->flags);
453 rev = ntohl(hdr->rev);
454
Greg Ungerer845884d2006-01-10 16:59:37 +1000455 if (strncmp(hdr->magic, "bFLT", 4)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700456 /*
Mike Frysingere2a366d2008-02-14 19:31:29 -0800457 * Previously, here was a printk to tell people
458 * "BINFMT_FLAT: bad header magic".
459 * But for the kernel which also use ELF FD-PIC format, this
460 * error message is confusing.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700461 * because a lot of people do not manage to produce good
Linus Torvalds1da177e2005-04-16 15:20:36 -0700462 */
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800463 ret = -ENOEXEC;
464 goto err;
Greg Ungerer845884d2006-01-10 16:59:37 +1000465 }
466
467 if (flags & FLAT_FLAG_KTRACE)
468 printk("BINFMT_FLAT: Loading file: %s\n", bprm->filename);
469
470 if (rev != FLAT_VERSION && rev != OLD_FLAT_VERSION) {
Andrew Morton0e647c02007-10-16 23:27:26 -0700471 printk("BINFMT_FLAT: bad flat file version 0x%x (supported "
472 "0x%lx and 0x%lx)\n",
473 rev, FLAT_VERSION, OLD_FLAT_VERSION);
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800474 ret = -ENOEXEC;
475 goto err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700476 }
477
478 /* Don't allow old format executables to use shared libraries */
479 if (rev == OLD_FLAT_VERSION && id != 0) {
480 printk("BINFMT_FLAT: shared libraries are not available before rev 0x%x\n",
481 (int) FLAT_VERSION);
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800482 ret = -ENOEXEC;
483 goto err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700484 }
485
486 /*
487 * fix up the flags for the older format, there were all kinds
488 * of endian hacks, this only works for the simple cases
489 */
490 if (rev == OLD_FLAT_VERSION && flat_old_ram_flag(flags))
491 flags = FLAT_FLAG_RAM;
492
493#ifndef CONFIG_BINFMT_ZFLAT
494 if (flags & (FLAT_FLAG_GZIP|FLAT_FLAG_GZDATA)) {
495 printk("Support for ZFLAT executables is not enabled.\n");
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800496 ret = -ENOEXEC;
497 goto err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700498 }
499#endif
500
501 /*
502 * Check initial limits. This avoids letting people circumvent
503 * size limits imposed on them by creating programs with large
504 * arrays in the data or bss.
505 */
Jiri Slabyd554ed892010-03-05 13:42:42 -0800506 rlim = rlimit(RLIMIT_DATA);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700507 if (rlim >= RLIM_INFINITY)
508 rlim = ~0;
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800509 if (data_len + bss_len > rlim) {
510 ret = -ENOMEM;
511 goto err;
512 }
513
Linus Torvalds1da177e2005-04-16 15:20:36 -0700514 /* Flush all traces of the currently running executable */
515 if (id == 0) {
516 result = flush_old_exec(bprm);
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800517 if (result) {
518 ret = result;
Andrew Mortondf889122006-05-20 15:00:01 -0700519 goto err;
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800520 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700521
522 /* OK, This is the point of no return */
Malcolm Parsonsfcc18e82006-06-26 11:49:41 +1000523 set_personality(PER_LINUX_32BIT);
Linus Torvalds221af7f2010-01-28 22:14:42 -0800524 setup_new_exec(bprm);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700525 }
526
527 /*
528 * calculate the extra space we need to map in
529 */
Andrew Morton0e647c02007-10-16 23:27:26 -0700530 extra = max_t(unsigned long, bss_len + stack_len,
531 relocs * sizeof(unsigned long));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700532
533 /*
534 * there are a couple of cases here, the separate code/data
535 * case, and then the fully copied to RAM case which lumps
536 * it all together.
537 */
538 if ((flags & (FLAT_FLAG_RAM|FLAT_FLAG_GZIP)) == 0) {
539 /*
540 * this should give us a ROM ptr, but if it doesn't we don't
541 * really care
542 */
543 DBG_FLT("BINFMT_FLAT: ROM mapping of file (we hope)\n");
544
Linus Torvalds6be5ceb2012-04-20 17:13:58 -0700545 textpos = vm_mmap(bprm->file, 0, text_len, PROT_READ|PROT_EXEC,
Matt Helsley925d1c42008-04-29 01:01:36 -0700546 MAP_PRIVATE|MAP_EXECUTABLE, 0);
Mike Frysinger0b8c78f2009-09-23 15:57:07 -0700547 if (!textpos || IS_ERR_VALUE(textpos)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700548 if (!textpos)
549 textpos = (unsigned long) -ENOMEM;
550 printk("Unable to mmap process text, errno %d\n", (int)-textpos);
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800551 ret = textpos;
Andrew Mortondf889122006-05-20 15:00:01 -0700552 goto err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700553 }
554
Greg Ungerer72613e5f2007-02-07 12:03:08 +1000555 len = data_len + extra + MAX_SHARED_LIBS * sizeof(unsigned long);
David Howells0f3e4422009-01-08 12:04:47 +0000556 len = PAGE_ALIGN(len);
Linus Torvalds6be5ceb2012-04-20 17:13:58 -0700557 realdatastart = vm_mmap(0, 0, len,
Greg Ungerer72613e5f2007-02-07 12:03:08 +1000558 PROT_READ|PROT_WRITE|PROT_EXEC, MAP_PRIVATE, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700559
Mike Frysinger0b8c78f2009-09-23 15:57:07 -0700560 if (realdatastart == 0 || IS_ERR_VALUE(realdatastart)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700561 if (!realdatastart)
562 realdatastart = (unsigned long) -ENOMEM;
563 printk("Unable to allocate RAM for process data, errno %d\n",
Greg Ungererc287ef12007-06-08 13:46:43 -0700564 (int)-realdatastart);
Al Viro7696e0c32012-05-30 01:56:23 -0400565 vm_munmap(textpos, text_len);
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800566 ret = realdatastart;
Andrew Mortondf889122006-05-20 15:00:01 -0700567 goto err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700568 }
Oskar Schirmerc3dc5be2009-05-28 14:34:31 -0700569 datapos = ALIGN(realdatastart +
570 MAX_SHARED_LIBS * sizeof(unsigned long),
571 FLAT_DATA_ALIGN);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700572
573 DBG_FLT("BINFMT_FLAT: Allocated data+bss+stack (%d bytes): %x\n",
574 (int)(data_len + bss_len + stack_len), (int)datapos);
575
576 fpos = ntohl(hdr->data_start);
577#ifdef CONFIG_BINFMT_ZFLAT
578 if (flags & FLAT_FLAG_GZDATA) {
579 result = decompress_exec(bprm, fpos, (char *) datapos,
580 data_len + (relocs * sizeof(unsigned long)), 0);
581 } else
582#endif
583 {
584 result = bprm->file->f_op->read(bprm->file, (char *) datapos,
585 data_len + (relocs * sizeof(unsigned long)), &fpos);
586 }
Mike Frysinger0b8c78f2009-09-23 15:57:07 -0700587 if (IS_ERR_VALUE(result)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700588 printk("Unable to read data+bss, errno %d\n", (int)-result);
Al Viro7696e0c32012-05-30 01:56:23 -0400589 vm_munmap(textpos, text_len);
590 vm_munmap(realdatastart, len);
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800591 ret = result;
Andrew Mortondf889122006-05-20 15:00:01 -0700592 goto err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700593 }
594
595 reloc = (unsigned long *) (datapos+(ntohl(hdr->reloc_start)-text_len));
596 memp = realdatastart;
David Howells0f3e4422009-01-08 12:04:47 +0000597 memp_size = len;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700598 } else {
599
Greg Ungerer72613e5f2007-02-07 12:03:08 +1000600 len = text_len + data_len + extra + MAX_SHARED_LIBS * sizeof(unsigned long);
David Howells0f3e4422009-01-08 12:04:47 +0000601 len = PAGE_ALIGN(len);
Linus Torvalds6be5ceb2012-04-20 17:13:58 -0700602 textpos = vm_mmap(0, 0, len,
Greg Ungerer72613e5f2007-02-07 12:03:08 +1000603 PROT_READ | PROT_EXEC | PROT_WRITE, MAP_PRIVATE, 0);
Greg Ungerer72613e5f2007-02-07 12:03:08 +1000604
Mike Frysinger0b8c78f2009-09-23 15:57:07 -0700605 if (!textpos || IS_ERR_VALUE(textpos)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700606 if (!textpos)
607 textpos = (unsigned long) -ENOMEM;
608 printk("Unable to allocate RAM for process text/data, errno %d\n",
609 (int)-textpos);
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800610 ret = textpos;
Andrew Mortondf889122006-05-20 15:00:01 -0700611 goto err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700612 }
613
614 realdatastart = textpos + ntohl(hdr->data_start);
Oskar Schirmerc3dc5be2009-05-28 14:34:31 -0700615 datapos = ALIGN(realdatastart +
616 MAX_SHARED_LIBS * sizeof(unsigned long),
617 FLAT_DATA_ALIGN);
618
619 reloc = (unsigned long *)
620 (datapos + (ntohl(hdr->reloc_start) - text_len));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700621 memp = textpos;
David Howells0f3e4422009-01-08 12:04:47 +0000622 memp_size = len;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700623#ifdef CONFIG_BINFMT_ZFLAT
624 /*
625 * load it all in and treat it like a RAM load from now on
626 */
627 if (flags & FLAT_FLAG_GZIP) {
628 result = decompress_exec(bprm, sizeof (struct flat_hdr),
629 (((char *) textpos) + sizeof (struct flat_hdr)),
630 (text_len + data_len + (relocs * sizeof(unsigned long))
631 - sizeof (struct flat_hdr)),
632 0);
633 memmove((void *) datapos, (void *) realdatastart,
634 data_len + (relocs * sizeof(unsigned long)));
635 } else if (flags & FLAT_FLAG_GZDATA) {
636 fpos = 0;
637 result = bprm->file->f_op->read(bprm->file,
638 (char *) textpos, text_len, &fpos);
Mike Frysinger0b8c78f2009-09-23 15:57:07 -0700639 if (!IS_ERR_VALUE(result))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700640 result = decompress_exec(bprm, text_len, (char *) datapos,
641 data_len + (relocs * sizeof(unsigned long)), 0);
642 }
643 else
644#endif
645 {
646 fpos = 0;
647 result = bprm->file->f_op->read(bprm->file,
648 (char *) textpos, text_len, &fpos);
Mike Frysinger0b8c78f2009-09-23 15:57:07 -0700649 if (!IS_ERR_VALUE(result)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700650 fpos = ntohl(hdr->data_start);
651 result = bprm->file->f_op->read(bprm->file, (char *) datapos,
652 data_len + (relocs * sizeof(unsigned long)), &fpos);
653 }
654 }
Mike Frysinger0b8c78f2009-09-23 15:57:07 -0700655 if (IS_ERR_VALUE(result)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700656 printk("Unable to read code+data+bss, errno %d\n",(int)-result);
Al Viro7696e0c32012-05-30 01:56:23 -0400657 vm_munmap(textpos, text_len + data_len + extra +
Linus Torvalds1da177e2005-04-16 15:20:36 -0700658 MAX_SHARED_LIBS * sizeof(unsigned long));
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800659 ret = result;
Andrew Mortondf889122006-05-20 15:00:01 -0700660 goto err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700661 }
662 }
663
664 if (flags & FLAT_FLAG_KTRACE)
665 printk("Mapping is %x, Entry point is %x, data_start is %x\n",
666 (int)textpos, 0x00ffffff&ntohl(hdr->entry), ntohl(hdr->data_start));
667
668 /* The main program needs a little extra setup in the task structure */
669 start_code = textpos + sizeof (struct flat_hdr);
670 end_code = textpos + text_len;
671 if (id == 0) {
672 current->mm->start_code = start_code;
673 current->mm->end_code = end_code;
674 current->mm->start_data = datapos;
675 current->mm->end_data = datapos + data_len;
676 /*
677 * set up the brk stuff, uses any slack left in data/bss/stack
678 * allocation. We put the brk after the bss (between the bss
679 * and stack) like other platforms.
David Howells0f3e4422009-01-08 12:04:47 +0000680 * Userspace code relies on the stack pointer starting out at
681 * an address right at the end of a page.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700682 */
683 current->mm->start_brk = datapos + data_len + bss_len;
684 current->mm->brk = (current->mm->start_brk + 3) & ~3;
David Howells0f3e4422009-01-08 12:04:47 +0000685 current->mm->context.end_brk = memp + memp_size - stack_len;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700686 }
687
688 if (flags & FLAT_FLAG_KTRACE)
689 printk("%s %s: TEXT=%x-%x DATA=%x-%x BSS=%x-%x\n",
690 id ? "Lib" : "Load", bprm->filename,
691 (int) start_code, (int) end_code,
692 (int) datapos,
693 (int) (datapos + data_len),
694 (int) (datapos + data_len),
695 (int) (((datapos + data_len + bss_len) + 3) & ~3));
696
697 text_len -= sizeof(struct flat_hdr); /* the real code len */
698
699 /* Store the current module values into the global library structure */
700 libinfo->lib_list[id].start_code = start_code;
701 libinfo->lib_list[id].start_data = datapos;
702 libinfo->lib_list[id].start_brk = datapos + data_len + bss_len;
703 libinfo->lib_list[id].text_len = text_len;
704 libinfo->lib_list[id].loaded = 1;
705 libinfo->lib_list[id].entry = (0x00ffffff & ntohl(hdr->entry)) + textpos;
706 libinfo->lib_list[id].build_date = ntohl(hdr->build_date);
707
708 /*
709 * We just load the allocations into some temporary memory to
710 * help simplify all this mumbo jumbo
711 *
712 * We've got two different sections of relocation entries.
Lucas De Marchi25985ed2011-03-30 22:57:33 -0300713 * The first is the GOT which resides at the beginning of the data segment
Linus Torvalds1da177e2005-04-16 15:20:36 -0700714 * and is terminated with a -1. This one can be relocated in place.
715 * The second is the extra relocation entries tacked after the image's
716 * data segment. These require a little more processing as the entry is
717 * really an offset into the image which contains an offset into the
718 * image.
719 */
720 if (flags & FLAT_FLAG_GOTPIC) {
721 for (rp = (unsigned long *)datapos; *rp != 0xffffffff; rp++) {
722 unsigned long addr;
723 if (*rp) {
724 addr = calc_reloc(*rp, libinfo, id, 0);
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800725 if (addr == RELOC_FAILED) {
726 ret = -ENOEXEC;
Andrew Mortondf889122006-05-20 15:00:01 -0700727 goto err;
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800728 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700729 *rp = addr;
730 }
731 }
732 }
733
734 /*
735 * Now run through the relocation entries.
736 * We've got to be careful here as C++ produces relocatable zero
737 * entries in the constructor and destructor tables which are then
738 * tested for being not zero (which will always occur unless we're
739 * based from address zero). This causes an endless loop as __start
740 * is at zero. The solution used is to not relocate zero addresses.
741 * This has the negative side effect of not allowing a global data
742 * reference to be statically initialised to _stext (I've moved
743 * __start to address 4 so that is okay).
744 */
745 if (rev > OLD_FLAT_VERSION) {
Bernd Schmidtf9720202007-10-03 23:41:43 +0800746 unsigned long persistent = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700747 for (i=0; i < relocs; i++) {
748 unsigned long addr, relval;
749
750 /* Get the address of the pointer to be
751 relocated (of course, the address has to be
752 relocated first). */
753 relval = ntohl(reloc[i]);
Bernd Schmidtf9720202007-10-03 23:41:43 +0800754 if (flat_set_persistent (relval, &persistent))
755 continue;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700756 addr = flat_get_relocate_addr(relval);
757 rp = (unsigned long *) calc_reloc(addr, libinfo, id, 1);
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800758 if (rp == (unsigned long *)RELOC_FAILED) {
759 ret = -ENOEXEC;
Andrew Mortondf889122006-05-20 15:00:01 -0700760 goto err;
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800761 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700762
763 /* Get the pointer's value. */
Andrew Morton576bb9c2007-10-03 23:43:57 +0800764 addr = flat_get_addr_from_rp(rp, relval, flags,
765 &persistent);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700766 if (addr != 0) {
767 /*
768 * Do the relocation. PIC relocs in the data section are
769 * already in target order
770 */
771 if ((flags & FLAT_FLAG_GOTPIC) == 0)
772 addr = ntohl(addr);
773 addr = calc_reloc(addr, libinfo, id, 0);
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800774 if (addr == RELOC_FAILED) {
775 ret = -ENOEXEC;
Andrew Mortondf889122006-05-20 15:00:01 -0700776 goto err;
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800777 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700778
779 /* Write back the relocated pointer. */
780 flat_put_addr_at_rp(rp, addr, relval);
781 }
782 }
783 } else {
784 for (i=0; i < relocs; i++)
785 old_reloc(ntohl(reloc[i]));
786 }
787
788 flush_icache_range(start_code, end_code);
789
790 /* zero the BSS, BRK and stack areas */
791 memset((void*)(datapos + data_len), 0, bss_len +
David Howells0f3e4422009-01-08 12:04:47 +0000792 (memp + memp_size - stack_len - /* end brk */
793 libinfo->lib_list[id].start_brk) + /* start brk */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700794 stack_len);
795
796 return 0;
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800797err:
798 return ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700799}
800
801
802/****************************************************************************/
803#ifdef CONFIG_BINFMT_SHARED_FLAT
804
805/*
806 * Load a shared library into memory. The library gets its own data
807 * segment (including bss) but not argv/argc/environ.
808 */
809
810static int load_flat_shared_library(int id, struct lib_info *libs)
811{
812 struct linux_binprm bprm;
813 int res;
814 char buf[16];
815
David Howells3a852d32011-04-28 16:26:38 +0100816 memset(&bprm, 0, sizeof(bprm));
817
Linus Torvalds1da177e2005-04-16 15:20:36 -0700818 /* Create the file name */
819 sprintf(buf, "/lib/lib%d.so", id);
820
821 /* Open the file up */
822 bprm.filename = buf;
823 bprm.file = open_exec(bprm.filename);
824 res = PTR_ERR(bprm.file);
825 if (IS_ERR(bprm.file))
826 return res;
827
Linus Torvalds34406252009-08-06 15:09:34 -0700828 bprm.cred = prepare_exec_creds();
829 res = -ENOMEM;
830 if (!bprm.cred)
831 goto out;
832
David Howells3a852d32011-04-28 16:26:38 +0100833 /* We don't really care about recalculating credentials at this point
834 * as we're past the point of no return and are dealing with shared
835 * libraries.
836 */
837 bprm.cred_prepared = 1;
838
Linus Torvalds1da177e2005-04-16 15:20:36 -0700839 res = prepare_binprm(&bprm);
840
Mike Frysinger0b8c78f2009-09-23 15:57:07 -0700841 if (!IS_ERR_VALUE(res))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700842 res = load_flat_file(&bprm, libs, id, NULL);
Linus Torvalds34406252009-08-06 15:09:34 -0700843
844 abort_creds(bprm.cred);
845
846out:
847 allow_write_access(bprm.file);
848 fput(bprm.file);
849
Linus Torvalds1da177e2005-04-16 15:20:36 -0700850 return(res);
851}
852
853#endif /* CONFIG_BINFMT_SHARED_FLAT */
854/****************************************************************************/
855
856/*
857 * These are the functions used to load flat style executables and shared
858 * libraries. There is no binary dependent code anywhere else.
859 */
860
861static int load_flat_binary(struct linux_binprm * bprm, struct pt_regs * regs)
862{
863 struct lib_info libinfo;
864 unsigned long p = bprm->p;
865 unsigned long stack_len;
866 unsigned long start_addr;
867 unsigned long *sp;
868 int res;
869 int i, j;
870
871 memset(&libinfo, 0, sizeof(libinfo));
872 /*
873 * We have to add the size of our arguments to our stack size
874 * otherwise it's too easy for users to create stack overflows
875 * by passing in a huge argument list. And yes, we have to be
876 * pedantic and include space for the argv/envp array as it may have
877 * a lot of entries.
878 */
879#define TOP_OF_ARGS (PAGE_SIZE * MAX_ARG_PAGES - sizeof(void *))
880 stack_len = TOP_OF_ARGS - bprm->p; /* the strings */
881 stack_len += (bprm->argc + 1) * sizeof(char *); /* the argv array */
882 stack_len += (bprm->envc + 1) * sizeof(char *); /* the envp array */
Mike Frysinger2e94de82010-06-04 14:14:53 -0700883 stack_len += FLAT_STACK_ALIGN - 1; /* reserve for upcoming alignment */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700884
885 res = load_flat_file(bprm, &libinfo, 0, &stack_len);
Mike Frysinger0b8c78f2009-09-23 15:57:07 -0700886 if (IS_ERR_VALUE(res))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700887 return res;
888
889 /* Update data segment pointers for all libraries */
890 for (i=0; i<MAX_SHARED_LIBS; i++)
891 if (libinfo.lib_list[i].loaded)
892 for (j=0; j<MAX_SHARED_LIBS; j++)
893 (-(j+1))[(unsigned long *)(libinfo.lib_list[i].start_data)] =
894 (libinfo.lib_list[j].loaded)?
895 libinfo.lib_list[j].start_data:UNLOADED_LIB;
896
David Howellsa6f76f22008-11-14 10:39:24 +1100897 install_exec_creds(bprm);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700898
899 set_binfmt(&flat_format);
900
901 p = ((current->mm->context.end_brk + stack_len + 3) & ~3) - 4;
902 DBG_FLT("p=%x\n", (int)p);
903
904 /* copy the arg pages onto the stack, this could be more efficient :-) */
905 for (i = TOP_OF_ARGS - 1; i >= bprm->p; i--)
906 * (char *) --p =
907 ((char *) page_address(bprm->page[i/PAGE_SIZE]))[i % PAGE_SIZE];
908
909 sp = (unsigned long *) create_flat_tables(p, bprm);
910
911 /* Fake some return addresses to ensure the call chain will
912 * initialise library in order for us. We are required to call
913 * lib 1 first, then 2, ... and finally the main program (id 0).
914 */
915 start_addr = libinfo.lib_list[0].entry;
916
917#ifdef CONFIG_BINFMT_SHARED_FLAT
918 for (i = MAX_SHARED_LIBS-1; i>0; i--) {
919 if (libinfo.lib_list[i].loaded) {
920 /* Push previos first to call address */
921 --sp; put_user(start_addr, sp);
922 start_addr = libinfo.lib_list[i].entry;
923 }
924 }
925#endif
926
927 /* Stash our initial stack pointer into the mm structure */
928 current->mm->start_stack = (unsigned long )sp;
929
Takashi YOSHII74c27c42008-08-11 20:10:54 +0900930#ifdef FLAT_PLAT_INIT
931 FLAT_PLAT_INIT(regs);
932#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700933 DBG_FLT("start_thread(regs=0x%x, entry=0x%x, start_stack=0x%x)\n",
934 (int)regs, (int)start_addr, (int)current->mm->start_stack);
935
936 start_thread(regs, start_addr, current->mm->start_stack);
937
Linus Torvalds1da177e2005-04-16 15:20:36 -0700938 return 0;
939}
940
941/****************************************************************************/
942
943static int __init init_flat_binfmt(void)
944{
Al Viro8fc3dc52012-03-17 03:05:16 -0400945 register_binfmt(&flat_format);
946 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700947}
948
Linus Torvalds1da177e2005-04-16 15:20:36 -0700949/****************************************************************************/
950
951core_initcall(init_flat_binfmt);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700952
953/****************************************************************************/