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-rw-r--r--fs/binfmt_flat.c901
1 files changed, 901 insertions, 0 deletions
diff --git a/fs/binfmt_flat.c b/fs/binfmt_flat.c
new file mode 100644
index 000000000000..f0cd67d9d31b
--- /dev/null
+++ b/fs/binfmt_flat.c
@@ -0,0 +1,901 @@
1/****************************************************************************/
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>
19#include <linux/config.h>
20#include <linux/kernel.h>
21#include <linux/sched.h>
22#include <linux/mm.h>
23#include <linux/mman.h>
24#include <linux/a.out.h>
25#include <linux/errno.h>
26#include <linux/signal.h>
27#include <linux/string.h>
28#include <linux/fs.h>
29#include <linux/file.h>
30#include <linux/stat.h>
31#include <linux/fcntl.h>
32#include <linux/ptrace.h>
33#include <linux/user.h>
34#include <linux/slab.h>
35#include <linux/binfmts.h>
36#include <linux/personality.h>
37#include <linux/init.h>
38#include <linux/flat.h>
39
40#include <asm/byteorder.h>
41#include <asm/system.h>
42#include <asm/uaccess.h>
43#include <asm/unaligned.h>
44#include <asm/cacheflush.h>
45
46/****************************************************************************/
47
48#if 0
49#define DEBUG 1
50#endif
51
52#ifdef DEBUG
53#define DBG_FLT(a...) printk(a)
54#else
55#define DBG_FLT(a...)
56#endif
57
58#define RELOC_FAILED 0xff00ff01 /* Relocation incorrect somewhere */
59#define UNLOADED_LIB 0x7ff000ff /* Placeholder for unused library */
60
61struct lib_info {
62 struct {
63 unsigned long start_code; /* Start of text segment */
64 unsigned long start_data; /* Start of data segment */
65 unsigned long start_brk; /* End of data segment */
66 unsigned long text_len; /* Length of text segment */
67 unsigned long entry; /* Start address for this module */
68 unsigned long build_date; /* When this one was compiled */
69 short loaded; /* Has this library been loaded? */
70 } lib_list[MAX_SHARED_LIBS];
71};
72
73#ifdef CONFIG_BINFMT_SHARED_FLAT
74static int load_flat_shared_library(int id, struct lib_info *p);
75#endif
76
77static int load_flat_binary(struct linux_binprm *, struct pt_regs * regs);
78static int flat_core_dump(long signr, struct pt_regs * regs, struct file *file);
79
80extern void dump_thread(struct pt_regs *, struct user *);
81
82static struct linux_binfmt flat_format = {
83 .module = THIS_MODULE,
84 .load_binary = load_flat_binary,
85 .core_dump = flat_core_dump,
86 .min_coredump = PAGE_SIZE
87};
88
89/****************************************************************************/
90/*
91 * Routine writes a core dump image in the current directory.
92 * Currently only a stub-function.
93 */
94
95static int flat_core_dump(long signr, struct pt_regs * regs, struct file *file)
96{
97 printk("Process %s:%d received signr %d and should have core dumped\n",
98 current->comm, current->pid, (int) signr);
99 return(1);
100}
101
102/****************************************************************************/
103/*
104 * create_flat_tables() parses the env- and arg-strings in new user
105 * memory and creates the pointer tables from them, and puts their
106 * addresses on the "stack", returning the new stack pointer value.
107 */
108
109static unsigned long create_flat_tables(
110 unsigned long pp,
111 struct linux_binprm * bprm)
112{
113 unsigned long *argv,*envp;
114 unsigned long * sp;
115 char * p = (char*)pp;
116 int argc = bprm->argc;
117 int envc = bprm->envc;
118 char dummy;
119
120 sp = (unsigned long *) ((-(unsigned long)sizeof(char *))&(unsigned long) p);
121
122 sp -= envc+1;
123 envp = sp;
124 sp -= argc+1;
125 argv = sp;
126
127 flat_stack_align(sp);
128 if (flat_argvp_envp_on_stack()) {
129 --sp; put_user((unsigned long) envp, sp);
130 --sp; put_user((unsigned long) argv, sp);
131 }
132
133 put_user(argc,--sp);
134 current->mm->arg_start = (unsigned long) p;
135 while (argc-->0) {
136 put_user((unsigned long) p, argv++);
137 do {
138 get_user(dummy, p); p++;
139 } while (dummy);
140 }
141 put_user((unsigned long) NULL, argv);
142 current->mm->arg_end = current->mm->env_start = (unsigned long) p;
143 while (envc-->0) {
144 put_user((unsigned long)p, envp); envp++;
145 do {
146 get_user(dummy, p); p++;
147 } while (dummy);
148 }
149 put_user((unsigned long) NULL, envp);
150 current->mm->env_end = (unsigned long) p;
151 return (unsigned long)sp;
152}
153
154/****************************************************************************/
155
156#ifdef CONFIG_BINFMT_ZFLAT
157
158#include <linux/zlib.h>
159
160#define LBUFSIZE 4000
161
162/* gzip flag byte */
163#define ASCII_FLAG 0x01 /* bit 0 set: file probably ASCII text */
164#define CONTINUATION 0x02 /* bit 1 set: continuation of multi-part gzip file */
165#define EXTRA_FIELD 0x04 /* bit 2 set: extra field present */
166#define ORIG_NAME 0x08 /* bit 3 set: original file name present */
167#define COMMENT 0x10 /* bit 4 set: file comment present */
168#define ENCRYPTED 0x20 /* bit 5 set: file is encrypted */
169#define RESERVED 0xC0 /* bit 6,7: reserved */
170
171static int decompress_exec(
172 struct linux_binprm *bprm,
173 unsigned long offset,
174 char *dst,
175 long len,
176 int fd)
177{
178 unsigned char *buf;
179 z_stream strm;
180 loff_t fpos;
181 int ret, retval;
182
183 DBG_FLT("decompress_exec(offset=%x,buf=%x,len=%x)\n",(int)offset, (int)dst, (int)len);
184
185 memset(&strm, 0, sizeof(strm));
186 strm.workspace = kmalloc(zlib_inflate_workspacesize(), GFP_KERNEL);
187 if (strm.workspace == NULL) {
188 DBG_FLT("binfmt_flat: no memory for decompress workspace\n");
189 return -ENOMEM;
190 }
191 buf = kmalloc(LBUFSIZE, GFP_KERNEL);
192 if (buf == NULL) {
193 DBG_FLT("binfmt_flat: no memory for read buffer\n");
194 retval = -ENOMEM;
195 goto out_free;
196 }
197
198 /* Read in first chunk of data and parse gzip header. */
199 fpos = offset;
200 ret = bprm->file->f_op->read(bprm->file, buf, LBUFSIZE, &fpos);
201
202 strm.next_in = buf;
203 strm.avail_in = ret;
204 strm.total_in = 0;
205
206 retval = -ENOEXEC;
207
208 /* Check minimum size -- gzip header */
209 if (ret < 10) {
210 DBG_FLT("binfmt_flat: file too small?\n");
211 goto out_free_buf;
212 }
213
214 /* Check gzip magic number */
215 if ((buf[0] != 037) || ((buf[1] != 0213) && (buf[1] != 0236))) {
216 DBG_FLT("binfmt_flat: unknown compression magic?\n");
217 goto out_free_buf;
218 }
219
220 /* Check gzip method */
221 if (buf[2] != 8) {
222 DBG_FLT("binfmt_flat: unknown compression method?\n");
223 goto out_free_buf;
224 }
225 /* Check gzip flags */
226 if ((buf[3] & ENCRYPTED) || (buf[3] & CONTINUATION) ||
227 (buf[3] & RESERVED)) {
228 DBG_FLT("binfmt_flat: unknown flags?\n");
229 goto out_free_buf;
230 }
231
232 ret = 10;
233 if (buf[3] & EXTRA_FIELD) {
234 ret += 2 + buf[10] + (buf[11] << 8);
235 if (unlikely(LBUFSIZE == ret)) {
236 DBG_FLT("binfmt_flat: buffer overflow (EXTRA)?\n");
237 goto out_free_buf;
238 }
239 }
240 if (buf[3] & ORIG_NAME) {
241 for (; ret < LBUFSIZE && (buf[ret] != 0); ret++)
242 ;
243 if (unlikely(LBUFSIZE == ret)) {
244 DBG_FLT("binfmt_flat: buffer overflow (ORIG_NAME)?\n");
245 goto out_free_buf;
246 }
247 }
248 if (buf[3] & COMMENT) {
249 for (; ret < LBUFSIZE && (buf[ret] != 0); ret++)
250 ;
251 if (unlikely(LBUFSIZE == ret)) {
252 DBG_FLT("binfmt_flat: buffer overflow (COMMENT)?\n");
253 goto out_free_buf;
254 }
255 }
256
257 strm.next_in += ret;
258 strm.avail_in -= ret;
259
260 strm.next_out = dst;
261 strm.avail_out = len;
262 strm.total_out = 0;
263
264 if (zlib_inflateInit2(&strm, -MAX_WBITS) != Z_OK) {
265 DBG_FLT("binfmt_flat: zlib init failed?\n");
266 goto out_free_buf;
267 }
268
269 while ((ret = zlib_inflate(&strm, Z_NO_FLUSH)) == Z_OK) {
270 ret = bprm->file->f_op->read(bprm->file, buf, LBUFSIZE, &fpos);
271 if (ret <= 0)
272 break;
273 if (ret >= (unsigned long) -4096)
274 break;
275 len -= ret;
276
277 strm.next_in = buf;
278 strm.avail_in = ret;
279 strm.total_in = 0;
280 }
281
282 if (ret < 0) {
283 DBG_FLT("binfmt_flat: decompression failed (%d), %s\n",
284 ret, strm.msg);
285 goto out_zlib;
286 }
287
288 retval = 0;
289out_zlib:
290 zlib_inflateEnd(&strm);
291out_free_buf:
292 kfree(buf);
293out_free:
294 kfree(strm.workspace);
295out:
296 return retval;
297}
298
299#endif /* CONFIG_BINFMT_ZFLAT */
300
301/****************************************************************************/
302
303static unsigned long
304calc_reloc(unsigned long r, struct lib_info *p, int curid, int internalp)
305{
306 unsigned long addr;
307 int id;
308 unsigned long start_brk;
309 unsigned long start_data;
310 unsigned long text_len;
311 unsigned long start_code;
312
313#ifdef CONFIG_BINFMT_SHARED_FLAT
314 if (r == 0)
315 id = curid; /* Relocs of 0 are always self referring */
316 else {
317 id = (r >> 24) & 0xff; /* Find ID for this reloc */
318 r &= 0x00ffffff; /* Trim ID off here */
319 }
320 if (id >= MAX_SHARED_LIBS) {
321 printk("BINFMT_FLAT: reference 0x%x to shared library %d",
322 (unsigned) r, id);
323 goto failed;
324 }
325 if (curid != id) {
326 if (internalp) {
327 printk("BINFMT_FLAT: reloc address 0x%x not in same module "
328 "(%d != %d)", (unsigned) r, curid, id);
329 goto failed;
330 } else if ( ! p->lib_list[id].loaded &&
331 load_flat_shared_library(id, p) > (unsigned long) -4096) {
332 printk("BINFMT_FLAT: failed to load library %d", id);
333 goto failed;
334 }
335 /* Check versioning information (i.e. time stamps) */
336 if (p->lib_list[id].build_date && p->lib_list[curid].build_date &&
337 p->lib_list[curid].build_date < p->lib_list[id].build_date) {
338 printk("BINFMT_FLAT: library %d is younger than %d", id, curid);
339 goto failed;
340 }
341 }
342#else
343 id = 0;
344#endif
345
346 start_brk = p->lib_list[id].start_brk;
347 start_data = p->lib_list[id].start_data;
348 start_code = p->lib_list[id].start_code;
349 text_len = p->lib_list[id].text_len;
350
351 if (!flat_reloc_valid(r, start_brk - start_data + text_len)) {
352 printk("BINFMT_FLAT: reloc outside program 0x%x (0 - 0x%x/0x%x)",
353 (int) r,(int)(start_brk-start_code),(int)text_len);
354 goto failed;
355 }
356
357 if (r < text_len) /* In text segment */
358 addr = r + start_code;
359 else /* In data segment */
360 addr = r - text_len + start_data;
361
362 /* Range checked already above so doing the range tests is redundant...*/
363 return(addr);
364
365failed:
366 printk(", killing %s!\n", current->comm);
367 send_sig(SIGSEGV, current, 0);
368
369 return RELOC_FAILED;
370}
371
372/****************************************************************************/
373
374void old_reloc(unsigned long rl)
375{
376#ifdef DEBUG
377 char *segment[] = { "TEXT", "DATA", "BSS", "*UNKNOWN*" };
378#endif
379 flat_v2_reloc_t r;
380 unsigned long *ptr;
381
382 r.value = rl;
383#if defined(CONFIG_COLDFIRE)
384 ptr = (unsigned long *) (current->mm->start_code + r.reloc.offset);
385#else
386 ptr = (unsigned long *) (current->mm->start_data + r.reloc.offset);
387#endif
388
389#ifdef DEBUG
390 printk("Relocation of variable at DATASEG+%x "
391 "(address %p, currently %x) into segment %s\n",
392 r.reloc.offset, ptr, (int)*ptr, segment[r.reloc.type]);
393#endif
394
395 switch (r.reloc.type) {
396 case OLD_FLAT_RELOC_TYPE_TEXT:
397 *ptr += current->mm->start_code;
398 break;
399 case OLD_FLAT_RELOC_TYPE_DATA:
400 *ptr += current->mm->start_data;
401 break;
402 case OLD_FLAT_RELOC_TYPE_BSS:
403 *ptr += current->mm->end_data;
404 break;
405 default:
406 printk("BINFMT_FLAT: Unknown relocation type=%x\n", r.reloc.type);
407 break;
408 }
409
410#ifdef DEBUG
411 printk("Relocation became %x\n", (int)*ptr);
412#endif
413}
414
415/****************************************************************************/
416
417static int load_flat_file(struct linux_binprm * bprm,
418 struct lib_info *libinfo, int id, unsigned long *extra_stack)
419{
420 struct flat_hdr * hdr;
421 unsigned long textpos = 0, datapos = 0, result;
422 unsigned long realdatastart = 0;
423 unsigned long text_len, data_len, bss_len, stack_len, flags;
424 unsigned long memp = 0; /* for finding the brk area */
425 unsigned long extra, rlim;
426 unsigned long *reloc = 0, *rp;
427 struct inode *inode;
428 int i, rev, relocs = 0;
429 loff_t fpos;
430 unsigned long start_code, end_code;
431
432 hdr = ((struct flat_hdr *) bprm->buf); /* exec-header */
433 inode = bprm->file->f_dentry->d_inode;
434
435 text_len = ntohl(hdr->data_start);
436 data_len = ntohl(hdr->data_end) - ntohl(hdr->data_start);
437 bss_len = ntohl(hdr->bss_end) - ntohl(hdr->data_end);
438 stack_len = ntohl(hdr->stack_size);
439 if (extra_stack) {
440 stack_len += *extra_stack;
441 *extra_stack = stack_len;
442 }
443 relocs = ntohl(hdr->reloc_count);
444 flags = ntohl(hdr->flags);
445 rev = ntohl(hdr->rev);
446
447 if (flags & FLAT_FLAG_KTRACE)
448 printk("BINFMT_FLAT: Loading file: %s\n", bprm->filename);
449
450 if (strncmp(hdr->magic, "bFLT", 4) ||
451 (rev != FLAT_VERSION && rev != OLD_FLAT_VERSION)) {
452 /*
453 * because a lot of people do not manage to produce good
454 * flat binaries, we leave this printk to help them realise
455 * the problem. We only print the error if its not a script file
456 */
457 if (strncmp(hdr->magic, "#!", 2))
458 printk("BINFMT_FLAT: bad magic/rev (0x%x, need 0x%x)\n",
459 rev, (int) FLAT_VERSION);
460 return -ENOEXEC;
461 }
462
463 /* Don't allow old format executables to use shared libraries */
464 if (rev == OLD_FLAT_VERSION && id != 0) {
465 printk("BINFMT_FLAT: shared libraries are not available before rev 0x%x\n",
466 (int) FLAT_VERSION);
467 return -ENOEXEC;
468 }
469
470 /*
471 * fix up the flags for the older format, there were all kinds
472 * of endian hacks, this only works for the simple cases
473 */
474 if (rev == OLD_FLAT_VERSION && flat_old_ram_flag(flags))
475 flags = FLAT_FLAG_RAM;
476
477#ifndef CONFIG_BINFMT_ZFLAT
478 if (flags & (FLAT_FLAG_GZIP|FLAT_FLAG_GZDATA)) {
479 printk("Support for ZFLAT executables is not enabled.\n");
480 return -ENOEXEC;
481 }
482#endif
483
484 /*
485 * Check initial limits. This avoids letting people circumvent
486 * size limits imposed on them by creating programs with large
487 * arrays in the data or bss.
488 */
489 rlim = current->signal->rlim[RLIMIT_DATA].rlim_cur;
490 if (rlim >= RLIM_INFINITY)
491 rlim = ~0;
492 if (data_len + bss_len > rlim)
493 return -ENOMEM;
494
495 /* Flush all traces of the currently running executable */
496 if (id == 0) {
497 result = flush_old_exec(bprm);
498 if (result)
499 return result;
500
501 /* OK, This is the point of no return */
502 set_personality(PER_LINUX);
503 }
504
505 /*
506 * calculate the extra space we need to map in
507 */
508 extra = max(bss_len + stack_len, relocs * sizeof(unsigned long));
509
510 /*
511 * there are a couple of cases here, the separate code/data
512 * case, and then the fully copied to RAM case which lumps
513 * it all together.
514 */
515 if ((flags & (FLAT_FLAG_RAM|FLAT_FLAG_GZIP)) == 0) {
516 /*
517 * this should give us a ROM ptr, but if it doesn't we don't
518 * really care
519 */
520 DBG_FLT("BINFMT_FLAT: ROM mapping of file (we hope)\n");
521
522 down_write(&current->mm->mmap_sem);
523 textpos = do_mmap(bprm->file, 0, text_len, PROT_READ|PROT_EXEC, 0, 0);
524 up_write(&current->mm->mmap_sem);
525 if (!textpos || textpos >= (unsigned long) -4096) {
526 if (!textpos)
527 textpos = (unsigned long) -ENOMEM;
528 printk("Unable to mmap process text, errno %d\n", (int)-textpos);
529 return(textpos);
530 }
531
532 down_write(&current->mm->mmap_sem);
533 realdatastart = do_mmap(0, 0, data_len + extra +
534 MAX_SHARED_LIBS * sizeof(unsigned long),
535 PROT_READ|PROT_WRITE|PROT_EXEC, 0, 0);
536 up_write(&current->mm->mmap_sem);
537
538 if (realdatastart == 0 || realdatastart >= (unsigned long)-4096) {
539 if (!realdatastart)
540 realdatastart = (unsigned long) -ENOMEM;
541 printk("Unable to allocate RAM for process data, errno %d\n",
542 (int)-datapos);
543 do_munmap(current->mm, textpos, text_len);
544 return realdatastart;
545 }
546 datapos = realdatastart + MAX_SHARED_LIBS * sizeof(unsigned long);
547
548 DBG_FLT("BINFMT_FLAT: Allocated data+bss+stack (%d bytes): %x\n",
549 (int)(data_len + bss_len + stack_len), (int)datapos);
550
551 fpos = ntohl(hdr->data_start);
552#ifdef CONFIG_BINFMT_ZFLAT
553 if (flags & FLAT_FLAG_GZDATA) {
554 result = decompress_exec(bprm, fpos, (char *) datapos,
555 data_len + (relocs * sizeof(unsigned long)), 0);
556 } else
557#endif
558 {
559 result = bprm->file->f_op->read(bprm->file, (char *) datapos,
560 data_len + (relocs * sizeof(unsigned long)), &fpos);
561 }
562 if (result >= (unsigned long)-4096) {
563 printk("Unable to read data+bss, errno %d\n", (int)-result);
564 do_munmap(current->mm, textpos, text_len);
565 do_munmap(current->mm, realdatastart, data_len + extra);
566 return result;
567 }
568
569 reloc = (unsigned long *) (datapos+(ntohl(hdr->reloc_start)-text_len));
570 memp = realdatastart;
571
572 } else {
573
574 down_write(&current->mm->mmap_sem);
575 textpos = do_mmap(0, 0, text_len + data_len + extra +
576 MAX_SHARED_LIBS * sizeof(unsigned long),
577 PROT_READ | PROT_EXEC | PROT_WRITE, 0, 0);
578 up_write(&current->mm->mmap_sem);
579 if (!textpos || textpos >= (unsigned long) -4096) {
580 if (!textpos)
581 textpos = (unsigned long) -ENOMEM;
582 printk("Unable to allocate RAM for process text/data, errno %d\n",
583 (int)-textpos);
584 return(textpos);
585 }
586
587 realdatastart = textpos + ntohl(hdr->data_start);
588 datapos = realdatastart + MAX_SHARED_LIBS * sizeof(unsigned long);
589 reloc = (unsigned long *) (textpos + ntohl(hdr->reloc_start) +
590 MAX_SHARED_LIBS * sizeof(unsigned long));
591 memp = textpos;
592
593#ifdef CONFIG_BINFMT_ZFLAT
594 /*
595 * load it all in and treat it like a RAM load from now on
596 */
597 if (flags & FLAT_FLAG_GZIP) {
598 result = decompress_exec(bprm, sizeof (struct flat_hdr),
599 (((char *) textpos) + sizeof (struct flat_hdr)),
600 (text_len + data_len + (relocs * sizeof(unsigned long))
601 - sizeof (struct flat_hdr)),
602 0);
603 memmove((void *) datapos, (void *) realdatastart,
604 data_len + (relocs * sizeof(unsigned long)));
605 } else if (flags & FLAT_FLAG_GZDATA) {
606 fpos = 0;
607 result = bprm->file->f_op->read(bprm->file,
608 (char *) textpos, text_len, &fpos);
609 if (result < (unsigned long) -4096)
610 result = decompress_exec(bprm, text_len, (char *) datapos,
611 data_len + (relocs * sizeof(unsigned long)), 0);
612 }
613 else
614#endif
615 {
616 fpos = 0;
617 result = bprm->file->f_op->read(bprm->file,
618 (char *) textpos, text_len, &fpos);
619 if (result < (unsigned long) -4096) {
620 fpos = ntohl(hdr->data_start);
621 result = bprm->file->f_op->read(bprm->file, (char *) datapos,
622 data_len + (relocs * sizeof(unsigned long)), &fpos);
623 }
624 }
625 if (result >= (unsigned long)-4096) {
626 printk("Unable to read code+data+bss, errno %d\n",(int)-result);
627 do_munmap(current->mm, textpos, text_len + data_len + extra +
628 MAX_SHARED_LIBS * sizeof(unsigned long));
629 return result;
630 }
631 }
632
633 if (flags & FLAT_FLAG_KTRACE)
634 printk("Mapping is %x, Entry point is %x, data_start is %x\n",
635 (int)textpos, 0x00ffffff&ntohl(hdr->entry), ntohl(hdr->data_start));
636
637 /* The main program needs a little extra setup in the task structure */
638 start_code = textpos + sizeof (struct flat_hdr);
639 end_code = textpos + text_len;
640 if (id == 0) {
641 current->mm->start_code = start_code;
642 current->mm->end_code = end_code;
643 current->mm->start_data = datapos;
644 current->mm->end_data = datapos + data_len;
645 /*
646 * set up the brk stuff, uses any slack left in data/bss/stack
647 * allocation. We put the brk after the bss (between the bss
648 * and stack) like other platforms.
649 */
650 current->mm->start_brk = datapos + data_len + bss_len;
651 current->mm->brk = (current->mm->start_brk + 3) & ~3;
652 current->mm->context.end_brk = memp + ksize((void *) memp) - stack_len;
653 set_mm_counter(current->mm, rss, 0);
654 }
655
656 if (flags & FLAT_FLAG_KTRACE)
657 printk("%s %s: TEXT=%x-%x DATA=%x-%x BSS=%x-%x\n",
658 id ? "Lib" : "Load", bprm->filename,
659 (int) start_code, (int) end_code,
660 (int) datapos,
661 (int) (datapos + data_len),
662 (int) (datapos + data_len),
663 (int) (((datapos + data_len + bss_len) + 3) & ~3));
664
665 text_len -= sizeof(struct flat_hdr); /* the real code len */
666
667 /* Store the current module values into the global library structure */
668 libinfo->lib_list[id].start_code = start_code;
669 libinfo->lib_list[id].start_data = datapos;
670 libinfo->lib_list[id].start_brk = datapos + data_len + bss_len;
671 libinfo->lib_list[id].text_len = text_len;
672 libinfo->lib_list[id].loaded = 1;
673 libinfo->lib_list[id].entry = (0x00ffffff & ntohl(hdr->entry)) + textpos;
674 libinfo->lib_list[id].build_date = ntohl(hdr->build_date);
675
676 /*
677 * We just load the allocations into some temporary memory to
678 * help simplify all this mumbo jumbo
679 *
680 * We've got two different sections of relocation entries.
681 * The first is the GOT which resides at the begining of the data segment
682 * and is terminated with a -1. This one can be relocated in place.
683 * The second is the extra relocation entries tacked after the image's
684 * data segment. These require a little more processing as the entry is
685 * really an offset into the image which contains an offset into the
686 * image.
687 */
688 if (flags & FLAT_FLAG_GOTPIC) {
689 for (rp = (unsigned long *)datapos; *rp != 0xffffffff; rp++) {
690 unsigned long addr;
691 if (*rp) {
692 addr = calc_reloc(*rp, libinfo, id, 0);
693 if (addr == RELOC_FAILED)
694 return -ENOEXEC;
695 *rp = addr;
696 }
697 }
698 }
699
700 /*
701 * Now run through the relocation entries.
702 * We've got to be careful here as C++ produces relocatable zero
703 * entries in the constructor and destructor tables which are then
704 * tested for being not zero (which will always occur unless we're
705 * based from address zero). This causes an endless loop as __start
706 * is at zero. The solution used is to not relocate zero addresses.
707 * This has the negative side effect of not allowing a global data
708 * reference to be statically initialised to _stext (I've moved
709 * __start to address 4 so that is okay).
710 */
711 if (rev > OLD_FLAT_VERSION) {
712 for (i=0; i < relocs; i++) {
713 unsigned long addr, relval;
714
715 /* Get the address of the pointer to be
716 relocated (of course, the address has to be
717 relocated first). */
718 relval = ntohl(reloc[i]);
719 addr = flat_get_relocate_addr(relval);
720 rp = (unsigned long *) calc_reloc(addr, libinfo, id, 1);
721 if (rp == (unsigned long *)RELOC_FAILED)
722 return -ENOEXEC;
723
724 /* Get the pointer's value. */
725 addr = flat_get_addr_from_rp(rp, relval, flags);
726 if (addr != 0) {
727 /*
728 * Do the relocation. PIC relocs in the data section are
729 * already in target order
730 */
731 if ((flags & FLAT_FLAG_GOTPIC) == 0)
732 addr = ntohl(addr);
733 addr = calc_reloc(addr, libinfo, id, 0);
734 if (addr == RELOC_FAILED)
735 return -ENOEXEC;
736
737 /* Write back the relocated pointer. */
738 flat_put_addr_at_rp(rp, addr, relval);
739 }
740 }
741 } else {
742 for (i=0; i < relocs; i++)
743 old_reloc(ntohl(reloc[i]));
744 }
745
746 flush_icache_range(start_code, end_code);
747
748 /* zero the BSS, BRK and stack areas */
749 memset((void*)(datapos + data_len), 0, bss_len +
750 (memp + ksize((void *) memp) - stack_len - /* end brk */
751 libinfo->lib_list[id].start_brk) + /* start brk */
752 stack_len);
753
754 return 0;
755}
756
757
758/****************************************************************************/
759#ifdef CONFIG_BINFMT_SHARED_FLAT
760
761/*
762 * Load a shared library into memory. The library gets its own data
763 * segment (including bss) but not argv/argc/environ.
764 */
765
766static int load_flat_shared_library(int id, struct lib_info *libs)
767{
768 struct linux_binprm bprm;
769 int res;
770 char buf[16];
771
772 /* Create the file name */
773 sprintf(buf, "/lib/lib%d.so", id);
774
775 /* Open the file up */
776 bprm.filename = buf;
777 bprm.file = open_exec(bprm.filename);
778 res = PTR_ERR(bprm.file);
779 if (IS_ERR(bprm.file))
780 return res;
781
782 res = prepare_binprm(&bprm);
783
784 if (res <= (unsigned long)-4096)
785 res = load_flat_file(&bprm, libs, id, NULL);
786 if (bprm.file) {
787 allow_write_access(bprm.file);
788 fput(bprm.file);
789 bprm.file = NULL;
790 }
791 return(res);
792}
793
794#endif /* CONFIG_BINFMT_SHARED_FLAT */
795/****************************************************************************/
796
797/*
798 * These are the functions used to load flat style executables and shared
799 * libraries. There is no binary dependent code anywhere else.
800 */
801
802static int load_flat_binary(struct linux_binprm * bprm, struct pt_regs * regs)
803{
804 struct lib_info libinfo;
805 unsigned long p = bprm->p;
806 unsigned long stack_len;
807 unsigned long start_addr;
808 unsigned long *sp;
809 int res;
810 int i, j;
811
812 memset(&libinfo, 0, sizeof(libinfo));
813 /*
814 * We have to add the size of our arguments to our stack size
815 * otherwise it's too easy for users to create stack overflows
816 * by passing in a huge argument list. And yes, we have to be
817 * pedantic and include space for the argv/envp array as it may have
818 * a lot of entries.
819 */
820#define TOP_OF_ARGS (PAGE_SIZE * MAX_ARG_PAGES - sizeof(void *))
821 stack_len = TOP_OF_ARGS - bprm->p; /* the strings */
822 stack_len += (bprm->argc + 1) * sizeof(char *); /* the argv array */
823 stack_len += (bprm->envc + 1) * sizeof(char *); /* the envp array */
824
825
826 res = load_flat_file(bprm, &libinfo, 0, &stack_len);
827 if (res > (unsigned long)-4096)
828 return res;
829
830 /* Update data segment pointers for all libraries */
831 for (i=0; i<MAX_SHARED_LIBS; i++)
832 if (libinfo.lib_list[i].loaded)
833 for (j=0; j<MAX_SHARED_LIBS; j++)
834 (-(j+1))[(unsigned long *)(libinfo.lib_list[i].start_data)] =
835 (libinfo.lib_list[j].loaded)?
836 libinfo.lib_list[j].start_data:UNLOADED_LIB;
837
838 compute_creds(bprm);
839 current->flags &= ~PF_FORKNOEXEC;
840
841 set_binfmt(&flat_format);
842
843 p = ((current->mm->context.end_brk + stack_len + 3) & ~3) - 4;
844 DBG_FLT("p=%x\n", (int)p);
845
846 /* copy the arg pages onto the stack, this could be more efficient :-) */
847 for (i = TOP_OF_ARGS - 1; i >= bprm->p; i--)
848 * (char *) --p =
849 ((char *) page_address(bprm->page[i/PAGE_SIZE]))[i % PAGE_SIZE];
850
851 sp = (unsigned long *) create_flat_tables(p, bprm);
852
853 /* Fake some return addresses to ensure the call chain will
854 * initialise library in order for us. We are required to call
855 * lib 1 first, then 2, ... and finally the main program (id 0).
856 */
857 start_addr = libinfo.lib_list[0].entry;
858
859#ifdef CONFIG_BINFMT_SHARED_FLAT
860 for (i = MAX_SHARED_LIBS-1; i>0; i--) {
861 if (libinfo.lib_list[i].loaded) {
862 /* Push previos first to call address */
863 --sp; put_user(start_addr, sp);
864 start_addr = libinfo.lib_list[i].entry;
865 }
866 }
867#endif
868
869 /* Stash our initial stack pointer into the mm structure */
870 current->mm->start_stack = (unsigned long )sp;
871
872
873 DBG_FLT("start_thread(regs=0x%x, entry=0x%x, start_stack=0x%x)\n",
874 (int)regs, (int)start_addr, (int)current->mm->start_stack);
875
876 start_thread(regs, start_addr, current->mm->start_stack);
877
878 if (current->ptrace & PT_PTRACED)
879 send_sig(SIGTRAP, current, 0);
880
881 return 0;
882}
883
884/****************************************************************************/
885
886static int __init init_flat_binfmt(void)
887{
888 return register_binfmt(&flat_format);
889}
890
891static void __exit exit_flat_binfmt(void)
892{
893 unregister_binfmt(&flat_format);
894}
895
896/****************************************************************************/
897
898core_initcall(init_flat_binfmt);
899module_exit(exit_flat_binfmt);
900
901/****************************************************************************/
generated by cgit v1.2.2 (git 2.25.0) at 2024-11-24 10:38:55 -0500