AppArmor: cleanup generated files correctly
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / fs / binfmt_flat.c
blob811384bec8de8d486a9aa7355d49b0195995e97a
1 /****************************************************************************/
2 /*
3 * linux/fs/binfmt_flat.c
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:
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)
18 #include <linux/module.h>
19 #include <linux/kernel.h>
20 #include <linux/sched.h>
21 #include <linux/mm.h>
22 #include <linux/mman.h>
23 #include <linux/errno.h>
24 #include <linux/signal.h>
25 #include <linux/string.h>
26 #include <linux/fs.h>
27 #include <linux/file.h>
28 #include <linux/stat.h>
29 #include <linux/fcntl.h>
30 #include <linux/ptrace.h>
31 #include <linux/user.h>
32 #include <linux/slab.h>
33 #include <linux/binfmts.h>
34 #include <linux/personality.h>
35 #include <linux/init.h>
36 #include <linux/flat.h>
37 #include <linux/syscalls.h>
39 #include <asm/byteorder.h>
40 #include <asm/system.h>
41 #include <asm/uaccess.h>
42 #include <asm/unaligned.h>
43 #include <asm/cacheflush.h>
44 #include <asm/page.h>
46 /****************************************************************************/
48 #if 0
49 #define DEBUG 1
50 #endif
52 #ifdef DEBUG
53 #define DBG_FLT(a...) printk(a)
54 #else
55 #define DBG_FLT(a...)
56 #endif
59 * User data (data section and bss) needs to be aligned.
60 * We pick 0x20 here because it is the max value elf2flt has always
61 * used in producing FLAT files, and because it seems to be large
62 * enough to make all the gcc alignment related tests happy.
64 #define FLAT_DATA_ALIGN (0x20)
67 * User data (stack) also needs to be aligned.
68 * Here we can be a bit looser than the data sections since this
69 * needs to only meet arch ABI requirements.
71 #define FLAT_STACK_ALIGN max_t(unsigned long, sizeof(void *), ARCH_SLAB_MINALIGN)
73 #define RELOC_FAILED 0xff00ff01 /* Relocation incorrect somewhere */
74 #define UNLOADED_LIB 0x7ff000ff /* Placeholder for unused library */
76 struct lib_info {
77 struct {
78 unsigned long start_code; /* Start of text segment */
79 unsigned long start_data; /* Start of data segment */
80 unsigned long start_brk; /* End of data segment */
81 unsigned long text_len; /* Length of text segment */
82 unsigned long entry; /* Start address for this module */
83 unsigned long build_date; /* When this one was compiled */
84 short loaded; /* Has this library been loaded? */
85 } lib_list[MAX_SHARED_LIBS];
88 #ifdef CONFIG_BINFMT_SHARED_FLAT
89 static int load_flat_shared_library(int id, struct lib_info *p);
90 #endif
92 static int load_flat_binary(struct linux_binprm *, struct pt_regs * regs);
93 static int flat_core_dump(struct coredump_params *cprm);
95 static struct linux_binfmt flat_format = {
96 .module = THIS_MODULE,
97 .load_binary = load_flat_binary,
98 .core_dump = flat_core_dump,
99 .min_coredump = PAGE_SIZE
102 /****************************************************************************/
104 * Routine writes a core dump image in the current directory.
105 * Currently only a stub-function.
108 static int flat_core_dump(struct coredump_params *cprm)
110 printk("Process %s:%d received signr %d and should have core dumped\n",
111 current->comm, current->pid, (int) cprm->signr);
112 return(1);
115 /****************************************************************************/
117 * create_flat_tables() parses the env- and arg-strings in new user
118 * memory and creates the pointer tables from them, and puts their
119 * addresses on the "stack", returning the new stack pointer value.
122 static unsigned long create_flat_tables(
123 unsigned long pp,
124 struct linux_binprm * bprm)
126 unsigned long *argv,*envp;
127 unsigned long * sp;
128 char * p = (char*)pp;
129 int argc = bprm->argc;
130 int envc = bprm->envc;
131 char uninitialized_var(dummy);
133 sp = (unsigned long *)p;
134 sp -= (envc + argc + 2) + 1 + (flat_argvp_envp_on_stack() ? 2 : 0);
135 sp = (unsigned long *) ((unsigned long)sp & -FLAT_STACK_ALIGN);
136 argv = sp + 1 + (flat_argvp_envp_on_stack() ? 2 : 0);
137 envp = argv + (argc + 1);
139 if (flat_argvp_envp_on_stack()) {
140 put_user((unsigned long) envp, sp + 2);
141 put_user((unsigned long) argv, sp + 1);
144 put_user(argc, sp);
145 current->mm->arg_start = (unsigned long) p;
146 while (argc-->0) {
147 put_user((unsigned long) p, argv++);
148 do {
149 get_user(dummy, p); p++;
150 } while (dummy);
152 put_user((unsigned long) NULL, argv);
153 current->mm->arg_end = current->mm->env_start = (unsigned long) p;
154 while (envc-->0) {
155 put_user((unsigned long)p, envp); envp++;
156 do {
157 get_user(dummy, p); p++;
158 } while (dummy);
160 put_user((unsigned long) NULL, envp);
161 current->mm->env_end = (unsigned long) p;
162 return (unsigned long)sp;
165 /****************************************************************************/
167 #ifdef CONFIG_BINFMT_ZFLAT
169 #include <linux/zlib.h>
171 #define LBUFSIZE 4000
173 /* gzip flag byte */
174 #define ASCII_FLAG 0x01 /* bit 0 set: file probably ASCII text */
175 #define CONTINUATION 0x02 /* bit 1 set: continuation of multi-part gzip file */
176 #define EXTRA_FIELD 0x04 /* bit 2 set: extra field present */
177 #define ORIG_NAME 0x08 /* bit 3 set: original file name present */
178 #define COMMENT 0x10 /* bit 4 set: file comment present */
179 #define ENCRYPTED 0x20 /* bit 5 set: file is encrypted */
180 #define RESERVED 0xC0 /* bit 6,7: reserved */
182 static int decompress_exec(
183 struct linux_binprm *bprm,
184 unsigned long offset,
185 char *dst,
186 long len,
187 int fd)
189 unsigned char *buf;
190 z_stream strm;
191 loff_t fpos;
192 int ret, retval;
194 DBG_FLT("decompress_exec(offset=%x,buf=%x,len=%x)\n",(int)offset, (int)dst, (int)len);
196 memset(&strm, 0, sizeof(strm));
197 strm.workspace = kmalloc(zlib_inflate_workspacesize(), GFP_KERNEL);
198 if (strm.workspace == NULL) {
199 DBG_FLT("binfmt_flat: no memory for decompress workspace\n");
200 return -ENOMEM;
202 buf = kmalloc(LBUFSIZE, GFP_KERNEL);
203 if (buf == NULL) {
204 DBG_FLT("binfmt_flat: no memory for read buffer\n");
205 retval = -ENOMEM;
206 goto out_free;
209 /* Read in first chunk of data and parse gzip header. */
210 fpos = offset;
211 ret = bprm->file->f_op->read(bprm->file, buf, LBUFSIZE, &fpos);
213 strm.next_in = buf;
214 strm.avail_in = ret;
215 strm.total_in = 0;
217 retval = -ENOEXEC;
219 /* Check minimum size -- gzip header */
220 if (ret < 10) {
221 DBG_FLT("binfmt_flat: file too small?\n");
222 goto out_free_buf;
225 /* Check gzip magic number */
226 if ((buf[0] != 037) || ((buf[1] != 0213) && (buf[1] != 0236))) {
227 DBG_FLT("binfmt_flat: unknown compression magic?\n");
228 goto out_free_buf;
231 /* Check gzip method */
232 if (buf[2] != 8) {
233 DBG_FLT("binfmt_flat: unknown compression method?\n");
234 goto out_free_buf;
236 /* Check gzip flags */
237 if ((buf[3] & ENCRYPTED) || (buf[3] & CONTINUATION) ||
238 (buf[3] & RESERVED)) {
239 DBG_FLT("binfmt_flat: unknown flags?\n");
240 goto out_free_buf;
243 ret = 10;
244 if (buf[3] & EXTRA_FIELD) {
245 ret += 2 + buf[10] + (buf[11] << 8);
246 if (unlikely(LBUFSIZE <= ret)) {
247 DBG_FLT("binfmt_flat: buffer overflow (EXTRA)?\n");
248 goto out_free_buf;
251 if (buf[3] & ORIG_NAME) {
252 while (ret < LBUFSIZE && buf[ret++] != 0)
254 if (unlikely(LBUFSIZE == ret)) {
255 DBG_FLT("binfmt_flat: buffer overflow (ORIG_NAME)?\n");
256 goto out_free_buf;
259 if (buf[3] & COMMENT) {
260 while (ret < LBUFSIZE && buf[ret++] != 0)
262 if (unlikely(LBUFSIZE == ret)) {
263 DBG_FLT("binfmt_flat: buffer overflow (COMMENT)?\n");
264 goto out_free_buf;
268 strm.next_in += ret;
269 strm.avail_in -= ret;
271 strm.next_out = dst;
272 strm.avail_out = len;
273 strm.total_out = 0;
275 if (zlib_inflateInit2(&strm, -MAX_WBITS) != Z_OK) {
276 DBG_FLT("binfmt_flat: zlib init failed?\n");
277 goto out_free_buf;
280 while ((ret = zlib_inflate(&strm, Z_NO_FLUSH)) == Z_OK) {
281 ret = bprm->file->f_op->read(bprm->file, buf, LBUFSIZE, &fpos);
282 if (ret <= 0)
283 break;
284 len -= ret;
286 strm.next_in = buf;
287 strm.avail_in = ret;
288 strm.total_in = 0;
291 if (ret < 0) {
292 DBG_FLT("binfmt_flat: decompression failed (%d), %s\n",
293 ret, strm.msg);
294 goto out_zlib;
297 retval = 0;
298 out_zlib:
299 zlib_inflateEnd(&strm);
300 out_free_buf:
301 kfree(buf);
302 out_free:
303 kfree(strm.workspace);
304 return retval;
307 #endif /* CONFIG_BINFMT_ZFLAT */
309 /****************************************************************************/
311 static unsigned long
312 calc_reloc(unsigned long r, struct lib_info *p, int curid, int internalp)
314 unsigned long addr;
315 int id;
316 unsigned long start_brk;
317 unsigned long start_data;
318 unsigned long text_len;
319 unsigned long start_code;
321 #ifdef CONFIG_BINFMT_SHARED_FLAT
322 if (r == 0)
323 id = curid; /* Relocs of 0 are always self referring */
324 else {
325 id = (r >> 24) & 0xff; /* Find ID for this reloc */
326 r &= 0x00ffffff; /* Trim ID off here */
328 if (id >= MAX_SHARED_LIBS) {
329 printk("BINFMT_FLAT: reference 0x%x to shared library %d",
330 (unsigned) r, id);
331 goto failed;
333 if (curid != id) {
334 if (internalp) {
335 printk("BINFMT_FLAT: reloc address 0x%x not in same module "
336 "(%d != %d)", (unsigned) r, curid, id);
337 goto failed;
338 } else if ( ! p->lib_list[id].loaded &&
339 IS_ERR_VALUE(load_flat_shared_library(id, p))) {
340 printk("BINFMT_FLAT: failed to load library %d", id);
341 goto failed;
343 /* Check versioning information (i.e. time stamps) */
344 if (p->lib_list[id].build_date && p->lib_list[curid].build_date &&
345 p->lib_list[curid].build_date < p->lib_list[id].build_date) {
346 printk("BINFMT_FLAT: library %d is younger than %d", id, curid);
347 goto failed;
350 #else
351 id = 0;
352 #endif
354 start_brk = p->lib_list[id].start_brk;
355 start_data = p->lib_list[id].start_data;
356 start_code = p->lib_list[id].start_code;
357 text_len = p->lib_list[id].text_len;
359 if (!flat_reloc_valid(r, start_brk - start_data + text_len)) {
360 printk("BINFMT_FLAT: reloc outside program 0x%x (0 - 0x%x/0x%x)",
361 (int) r,(int)(start_brk-start_data+text_len),(int)text_len);
362 goto failed;
365 if (r < text_len) /* In text segment */
366 addr = r + start_code;
367 else /* In data segment */
368 addr = r - text_len + start_data;
370 /* Range checked already above so doing the range tests is redundant...*/
371 return(addr);
373 failed:
374 printk(", killing %s!\n", current->comm);
375 send_sig(SIGSEGV, current, 0);
377 return RELOC_FAILED;
380 /****************************************************************************/
382 void old_reloc(unsigned long rl)
384 #ifdef DEBUG
385 char *segment[] = { "TEXT", "DATA", "BSS", "*UNKNOWN*" };
386 #endif
387 flat_v2_reloc_t r;
388 unsigned long *ptr;
390 r.value = rl;
391 #if defined(CONFIG_COLDFIRE)
392 ptr = (unsigned long *) (current->mm->start_code + r.reloc.offset);
393 #else
394 ptr = (unsigned long *) (current->mm->start_data + r.reloc.offset);
395 #endif
397 #ifdef DEBUG
398 printk("Relocation of variable at DATASEG+%x "
399 "(address %p, currently %x) into segment %s\n",
400 r.reloc.offset, ptr, (int)*ptr, segment[r.reloc.type]);
401 #endif
403 switch (r.reloc.type) {
404 case OLD_FLAT_RELOC_TYPE_TEXT:
405 *ptr += current->mm->start_code;
406 break;
407 case OLD_FLAT_RELOC_TYPE_DATA:
408 *ptr += current->mm->start_data;
409 break;
410 case OLD_FLAT_RELOC_TYPE_BSS:
411 *ptr += current->mm->end_data;
412 break;
413 default:
414 printk("BINFMT_FLAT: Unknown relocation type=%x\n", r.reloc.type);
415 break;
418 #ifdef DEBUG
419 printk("Relocation became %x\n", (int)*ptr);
420 #endif
423 /****************************************************************************/
425 static int load_flat_file(struct linux_binprm * bprm,
426 struct lib_info *libinfo, int id, unsigned long *extra_stack)
428 struct flat_hdr * hdr;
429 unsigned long textpos = 0, datapos = 0, result;
430 unsigned long realdatastart = 0;
431 unsigned long text_len, data_len, bss_len, stack_len, flags;
432 unsigned long len, memp = 0;
433 unsigned long memp_size, extra, rlim;
434 unsigned long *reloc = 0, *rp;
435 struct inode *inode;
436 int i, rev, relocs = 0;
437 loff_t fpos;
438 unsigned long start_code, end_code;
439 int ret;
441 hdr = ((struct flat_hdr *) bprm->buf); /* exec-header */
442 inode = bprm->file->f_path.dentry->d_inode;
444 text_len = ntohl(hdr->data_start);
445 data_len = ntohl(hdr->data_end) - ntohl(hdr->data_start);
446 bss_len = ntohl(hdr->bss_end) - ntohl(hdr->data_end);
447 stack_len = ntohl(hdr->stack_size);
448 if (extra_stack) {
449 stack_len += *extra_stack;
450 *extra_stack = stack_len;
452 relocs = ntohl(hdr->reloc_count);
453 flags = ntohl(hdr->flags);
454 rev = ntohl(hdr->rev);
456 if (strncmp(hdr->magic, "bFLT", 4)) {
458 * Previously, here was a printk to tell people
459 * "BINFMT_FLAT: bad header magic".
460 * But for the kernel which also use ELF FD-PIC format, this
461 * error message is confusing.
462 * because a lot of people do not manage to produce good
464 ret = -ENOEXEC;
465 goto err;
468 if (flags & FLAT_FLAG_KTRACE)
469 printk("BINFMT_FLAT: Loading file: %s\n", bprm->filename);
471 if (rev != FLAT_VERSION && rev != OLD_FLAT_VERSION) {
472 printk("BINFMT_FLAT: bad flat file version 0x%x (supported "
473 "0x%lx and 0x%lx)\n",
474 rev, FLAT_VERSION, OLD_FLAT_VERSION);
475 ret = -ENOEXEC;
476 goto err;
479 /* Don't allow old format executables to use shared libraries */
480 if (rev == OLD_FLAT_VERSION && id != 0) {
481 printk("BINFMT_FLAT: shared libraries are not available before rev 0x%x\n",
482 (int) FLAT_VERSION);
483 ret = -ENOEXEC;
484 goto err;
488 * fix up the flags for the older format, there were all kinds
489 * of endian hacks, this only works for the simple cases
491 if (rev == OLD_FLAT_VERSION && flat_old_ram_flag(flags))
492 flags = FLAT_FLAG_RAM;
494 #ifndef CONFIG_BINFMT_ZFLAT
495 if (flags & (FLAT_FLAG_GZIP|FLAT_FLAG_GZDATA)) {
496 printk("Support for ZFLAT executables is not enabled.\n");
497 ret = -ENOEXEC;
498 goto err;
500 #endif
503 * Check initial limits. This avoids letting people circumvent
504 * size limits imposed on them by creating programs with large
505 * arrays in the data or bss.
507 rlim = rlimit(RLIMIT_DATA);
508 if (rlim >= RLIM_INFINITY)
509 rlim = ~0;
510 if (data_len + bss_len > rlim) {
511 ret = -ENOMEM;
512 goto err;
515 /* Flush all traces of the currently running executable */
516 if (id == 0) {
517 result = flush_old_exec(bprm);
518 if (result) {
519 ret = result;
520 goto err;
523 /* OK, This is the point of no return */
524 set_personality(PER_LINUX_32BIT);
525 setup_new_exec(bprm);
529 * calculate the extra space we need to map in
531 extra = max_t(unsigned long, bss_len + stack_len,
532 relocs * sizeof(unsigned long));
535 * there are a couple of cases here, the separate code/data
536 * case, and then the fully copied to RAM case which lumps
537 * it all together.
539 if ((flags & (FLAT_FLAG_RAM|FLAT_FLAG_GZIP)) == 0) {
541 * this should give us a ROM ptr, but if it doesn't we don't
542 * really care
544 DBG_FLT("BINFMT_FLAT: ROM mapping of file (we hope)\n");
546 down_write(&current->mm->mmap_sem);
547 textpos = do_mmap(bprm->file, 0, text_len, PROT_READ|PROT_EXEC,
548 MAP_PRIVATE|MAP_EXECUTABLE, 0);
549 up_write(&current->mm->mmap_sem);
550 if (!textpos || IS_ERR_VALUE(textpos)) {
551 if (!textpos)
552 textpos = (unsigned long) -ENOMEM;
553 printk("Unable to mmap process text, errno %d\n", (int)-textpos);
554 ret = textpos;
555 goto err;
558 len = data_len + extra + MAX_SHARED_LIBS * sizeof(unsigned long);
559 len = PAGE_ALIGN(len);
560 down_write(&current->mm->mmap_sem);
561 realdatastart = do_mmap(0, 0, len,
562 PROT_READ|PROT_WRITE|PROT_EXEC, MAP_PRIVATE, 0);
563 up_write(&current->mm->mmap_sem);
565 if (realdatastart == 0 || IS_ERR_VALUE(realdatastart)) {
566 if (!realdatastart)
567 realdatastart = (unsigned long) -ENOMEM;
568 printk("Unable to allocate RAM for process data, errno %d\n",
569 (int)-realdatastart);
570 do_munmap(current->mm, textpos, text_len);
571 ret = realdatastart;
572 goto err;
574 datapos = ALIGN(realdatastart +
575 MAX_SHARED_LIBS * sizeof(unsigned long),
576 FLAT_DATA_ALIGN);
578 DBG_FLT("BINFMT_FLAT: Allocated data+bss+stack (%d bytes): %x\n",
579 (int)(data_len + bss_len + stack_len), (int)datapos);
581 fpos = ntohl(hdr->data_start);
582 #ifdef CONFIG_BINFMT_ZFLAT
583 if (flags & FLAT_FLAG_GZDATA) {
584 result = decompress_exec(bprm, fpos, (char *) datapos,
585 data_len + (relocs * sizeof(unsigned long)), 0);
586 } else
587 #endif
589 result = bprm->file->f_op->read(bprm->file, (char *) datapos,
590 data_len + (relocs * sizeof(unsigned long)), &fpos);
592 if (IS_ERR_VALUE(result)) {
593 printk("Unable to read data+bss, errno %d\n", (int)-result);
594 do_munmap(current->mm, textpos, text_len);
595 do_munmap(current->mm, realdatastart, len);
596 ret = result;
597 goto err;
600 reloc = (unsigned long *) (datapos+(ntohl(hdr->reloc_start)-text_len));
601 memp = realdatastart;
602 memp_size = len;
603 } else {
605 len = text_len + data_len + extra + MAX_SHARED_LIBS * sizeof(unsigned long);
606 len = PAGE_ALIGN(len);
607 down_write(&current->mm->mmap_sem);
608 textpos = do_mmap(0, 0, len,
609 PROT_READ | PROT_EXEC | PROT_WRITE, MAP_PRIVATE, 0);
610 up_write(&current->mm->mmap_sem);
612 if (!textpos || IS_ERR_VALUE(textpos)) {
613 if (!textpos)
614 textpos = (unsigned long) -ENOMEM;
615 printk("Unable to allocate RAM for process text/data, errno %d\n",
616 (int)-textpos);
617 ret = textpos;
618 goto err;
621 realdatastart = textpos + ntohl(hdr->data_start);
622 datapos = ALIGN(realdatastart +
623 MAX_SHARED_LIBS * sizeof(unsigned long),
624 FLAT_DATA_ALIGN);
626 reloc = (unsigned long *)
627 (datapos + (ntohl(hdr->reloc_start) - text_len));
628 memp = textpos;
629 memp_size = len;
630 #ifdef CONFIG_BINFMT_ZFLAT
632 * load it all in and treat it like a RAM load from now on
634 if (flags & FLAT_FLAG_GZIP) {
635 result = decompress_exec(bprm, sizeof (struct flat_hdr),
636 (((char *) textpos) + sizeof (struct flat_hdr)),
637 (text_len + data_len + (relocs * sizeof(unsigned long))
638 - sizeof (struct flat_hdr)),
640 memmove((void *) datapos, (void *) realdatastart,
641 data_len + (relocs * sizeof(unsigned long)));
642 } else if (flags & FLAT_FLAG_GZDATA) {
643 fpos = 0;
644 result = bprm->file->f_op->read(bprm->file,
645 (char *) textpos, text_len, &fpos);
646 if (!IS_ERR_VALUE(result))
647 result = decompress_exec(bprm, text_len, (char *) datapos,
648 data_len + (relocs * sizeof(unsigned long)), 0);
650 else
651 #endif
653 fpos = 0;
654 result = bprm->file->f_op->read(bprm->file,
655 (char *) textpos, text_len, &fpos);
656 if (!IS_ERR_VALUE(result)) {
657 fpos = ntohl(hdr->data_start);
658 result = bprm->file->f_op->read(bprm->file, (char *) datapos,
659 data_len + (relocs * sizeof(unsigned long)), &fpos);
662 if (IS_ERR_VALUE(result)) {
663 printk("Unable to read code+data+bss, errno %d\n",(int)-result);
664 do_munmap(current->mm, textpos, text_len + data_len + extra +
665 MAX_SHARED_LIBS * sizeof(unsigned long));
666 ret = result;
667 goto err;
671 if (flags & FLAT_FLAG_KTRACE)
672 printk("Mapping is %x, Entry point is %x, data_start is %x\n",
673 (int)textpos, 0x00ffffff&ntohl(hdr->entry), ntohl(hdr->data_start));
675 /* The main program needs a little extra setup in the task structure */
676 start_code = textpos + sizeof (struct flat_hdr);
677 end_code = textpos + text_len;
678 if (id == 0) {
679 current->mm->start_code = start_code;
680 current->mm->end_code = end_code;
681 current->mm->start_data = datapos;
682 current->mm->end_data = datapos + data_len;
684 * set up the brk stuff, uses any slack left in data/bss/stack
685 * allocation. We put the brk after the bss (between the bss
686 * and stack) like other platforms.
687 * Userspace code relies on the stack pointer starting out at
688 * an address right at the end of a page.
690 current->mm->start_brk = datapos + data_len + bss_len;
691 current->mm->brk = (current->mm->start_brk + 3) & ~3;
692 current->mm->context.end_brk = memp + memp_size - stack_len;
695 if (flags & FLAT_FLAG_KTRACE)
696 printk("%s %s: TEXT=%x-%x DATA=%x-%x BSS=%x-%x\n",
697 id ? "Lib" : "Load", bprm->filename,
698 (int) start_code, (int) end_code,
699 (int) datapos,
700 (int) (datapos + data_len),
701 (int) (datapos + data_len),
702 (int) (((datapos + data_len + bss_len) + 3) & ~3));
704 text_len -= sizeof(struct flat_hdr); /* the real code len */
706 /* Store the current module values into the global library structure */
707 libinfo->lib_list[id].start_code = start_code;
708 libinfo->lib_list[id].start_data = datapos;
709 libinfo->lib_list[id].start_brk = datapos + data_len + bss_len;
710 libinfo->lib_list[id].text_len = text_len;
711 libinfo->lib_list[id].loaded = 1;
712 libinfo->lib_list[id].entry = (0x00ffffff & ntohl(hdr->entry)) + textpos;
713 libinfo->lib_list[id].build_date = ntohl(hdr->build_date);
716 * We just load the allocations into some temporary memory to
717 * help simplify all this mumbo jumbo
719 * We've got two different sections of relocation entries.
720 * The first is the GOT which resides at the begining of the data segment
721 * and is terminated with a -1. This one can be relocated in place.
722 * The second is the extra relocation entries tacked after the image's
723 * data segment. These require a little more processing as the entry is
724 * really an offset into the image which contains an offset into the
725 * image.
727 if (flags & FLAT_FLAG_GOTPIC) {
728 for (rp = (unsigned long *)datapos; *rp != 0xffffffff; rp++) {
729 unsigned long addr;
730 if (*rp) {
731 addr = calc_reloc(*rp, libinfo, id, 0);
732 if (addr == RELOC_FAILED) {
733 ret = -ENOEXEC;
734 goto err;
736 *rp = addr;
742 * Now run through the relocation entries.
743 * We've got to be careful here as C++ produces relocatable zero
744 * entries in the constructor and destructor tables which are then
745 * tested for being not zero (which will always occur unless we're
746 * based from address zero). This causes an endless loop as __start
747 * is at zero. The solution used is to not relocate zero addresses.
748 * This has the negative side effect of not allowing a global data
749 * reference to be statically initialised to _stext (I've moved
750 * __start to address 4 so that is okay).
752 if (rev > OLD_FLAT_VERSION) {
753 unsigned long persistent = 0;
754 for (i=0; i < relocs; i++) {
755 unsigned long addr, relval;
757 /* Get the address of the pointer to be
758 relocated (of course, the address has to be
759 relocated first). */
760 relval = ntohl(reloc[i]);
761 if (flat_set_persistent (relval, &persistent))
762 continue;
763 addr = flat_get_relocate_addr(relval);
764 rp = (unsigned long *) calc_reloc(addr, libinfo, id, 1);
765 if (rp == (unsigned long *)RELOC_FAILED) {
766 ret = -ENOEXEC;
767 goto err;
770 /* Get the pointer's value. */
771 addr = flat_get_addr_from_rp(rp, relval, flags,
772 &persistent);
773 if (addr != 0) {
775 * Do the relocation. PIC relocs in the data section are
776 * already in target order
778 if ((flags & FLAT_FLAG_GOTPIC) == 0)
779 addr = ntohl(addr);
780 addr = calc_reloc(addr, libinfo, id, 0);
781 if (addr == RELOC_FAILED) {
782 ret = -ENOEXEC;
783 goto err;
786 /* Write back the relocated pointer. */
787 flat_put_addr_at_rp(rp, addr, relval);
790 } else {
791 for (i=0; i < relocs; i++)
792 old_reloc(ntohl(reloc[i]));
795 flush_icache_range(start_code, end_code);
797 /* zero the BSS, BRK and stack areas */
798 memset((void*)(datapos + data_len), 0, bss_len +
799 (memp + memp_size - stack_len - /* end brk */
800 libinfo->lib_list[id].start_brk) + /* start brk */
801 stack_len);
803 return 0;
804 err:
805 return ret;
809 /****************************************************************************/
810 #ifdef CONFIG_BINFMT_SHARED_FLAT
813 * Load a shared library into memory. The library gets its own data
814 * segment (including bss) but not argv/argc/environ.
817 static int load_flat_shared_library(int id, struct lib_info *libs)
819 struct linux_binprm bprm;
820 int res;
821 char buf[16];
823 /* Create the file name */
824 sprintf(buf, "/lib/lib%d.so", id);
826 /* Open the file up */
827 bprm.filename = buf;
828 bprm.file = open_exec(bprm.filename);
829 res = PTR_ERR(bprm.file);
830 if (IS_ERR(bprm.file))
831 return res;
833 bprm.cred = prepare_exec_creds();
834 res = -ENOMEM;
835 if (!bprm.cred)
836 goto out;
838 res = prepare_binprm(&bprm);
840 if (!IS_ERR_VALUE(res))
841 res = load_flat_file(&bprm, libs, id, NULL);
843 abort_creds(bprm.cred);
845 out:
846 allow_write_access(bprm.file);
847 fput(bprm.file);
849 return(res);
852 #endif /* CONFIG_BINFMT_SHARED_FLAT */
853 /****************************************************************************/
856 * These are the functions used to load flat style executables and shared
857 * libraries. There is no binary dependent code anywhere else.
860 static int load_flat_binary(struct linux_binprm * bprm, struct pt_regs * regs)
862 struct lib_info libinfo;
863 unsigned long p = bprm->p;
864 unsigned long stack_len;
865 unsigned long start_addr;
866 unsigned long *sp;
867 int res;
868 int i, j;
870 memset(&libinfo, 0, sizeof(libinfo));
872 * We have to add the size of our arguments to our stack size
873 * otherwise it's too easy for users to create stack overflows
874 * by passing in a huge argument list. And yes, we have to be
875 * pedantic and include space for the argv/envp array as it may have
876 * a lot of entries.
878 #define TOP_OF_ARGS (PAGE_SIZE * MAX_ARG_PAGES - sizeof(void *))
879 stack_len = TOP_OF_ARGS - bprm->p; /* the strings */
880 stack_len += (bprm->argc + 1) * sizeof(char *); /* the argv array */
881 stack_len += (bprm->envc + 1) * sizeof(char *); /* the envp array */
882 stack_len += FLAT_STACK_ALIGN - 1; /* reserve for upcoming alignment */
884 res = load_flat_file(bprm, &libinfo, 0, &stack_len);
885 if (IS_ERR_VALUE(res))
886 return res;
888 /* Update data segment pointers for all libraries */
889 for (i=0; i<MAX_SHARED_LIBS; i++)
890 if (libinfo.lib_list[i].loaded)
891 for (j=0; j<MAX_SHARED_LIBS; j++)
892 (-(j+1))[(unsigned long *)(libinfo.lib_list[i].start_data)] =
893 (libinfo.lib_list[j].loaded)?
894 libinfo.lib_list[j].start_data:UNLOADED_LIB;
896 install_exec_creds(bprm);
897 current->flags &= ~PF_FORKNOEXEC;
899 set_binfmt(&flat_format);
901 p = ((current->mm->context.end_brk + stack_len + 3) & ~3) - 4;
902 DBG_FLT("p=%x\n", (int)p);
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];
909 sp = (unsigned long *) create_flat_tables(p, bprm);
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).
915 start_addr = libinfo.lib_list[0].entry;
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;
925 #endif
927 /* Stash our initial stack pointer into the mm structure */
928 current->mm->start_stack = (unsigned long )sp;
930 #ifdef FLAT_PLAT_INIT
931 FLAT_PLAT_INIT(regs);
932 #endif
933 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);
936 start_thread(regs, start_addr, current->mm->start_stack);
938 return 0;
941 /****************************************************************************/
943 static int __init init_flat_binfmt(void)
945 return register_binfmt(&flat_format);
948 /****************************************************************************/
950 core_initcall(init_flat_binfmt);
952 /****************************************************************************/