thermal: re-document thermal units
[linux-2.6.git] / fs / binfmt_flat.c
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/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>
38
39 #include <asm/byteorder.h>
40 #include <asm/system.h>
41 #include <asm/uaccess.h>
42 #include <asm/unaligned.h>
43 #include <asm/cacheflush.h>
44
45 /****************************************************************************/
46
47 #if 0
48 #define DEBUG 1
49 #endif
50
51 #ifdef DEBUG
52 #define DBG_FLT(a...)   printk(a)
53 #else
54 #define DBG_FLT(a...)
55 #endif
56
57 #define RELOC_FAILED 0xff00ff01         /* Relocation incorrect somewhere */
58 #define UNLOADED_LIB 0x7ff000ff         /* Placeholder for unused library */
59
60 struct lib_info {
61         struct {
62                 unsigned long start_code;               /* Start of text segment */
63                 unsigned long start_data;               /* Start of data segment */
64                 unsigned long start_brk;                /* End of data segment */
65                 unsigned long text_len;                 /* Length of text segment */
66                 unsigned long entry;                    /* Start address for this module */
67                 unsigned long build_date;               /* When this one was compiled */
68                 short loaded;                           /* Has this library been loaded? */
69         } lib_list[MAX_SHARED_LIBS];
70 };
71
72 #ifdef CONFIG_BINFMT_SHARED_FLAT
73 static int load_flat_shared_library(int id, struct lib_info *p);
74 #endif
75
76 static int load_flat_binary(struct linux_binprm *, struct pt_regs * regs);
77 static int flat_core_dump(long signr, struct pt_regs *regs, struct file *file, unsigned long limit);
78
79 static struct linux_binfmt flat_format = {
80         .module         = THIS_MODULE,
81         .load_binary    = load_flat_binary,
82         .core_dump      = flat_core_dump,
83         .min_coredump   = PAGE_SIZE
84 };
85
86 /****************************************************************************/
87 /*
88  * Routine writes a core dump image in the current directory.
89  * Currently only a stub-function.
90  */
91
92 static int flat_core_dump(long signr, struct pt_regs *regs, struct file *file, unsigned long limit)
93 {
94         printk("Process %s:%d received signr %d and should have core dumped\n",
95                         current->comm, current->pid, (int) signr);
96         return(1);
97 }
98
99 /****************************************************************************/
100 /*
101  * create_flat_tables() parses the env- and arg-strings in new user
102  * memory and creates the pointer tables from them, and puts their
103  * addresses on the "stack", returning the new stack pointer value.
104  */
105
106 static unsigned long create_flat_tables(
107         unsigned long pp,
108         struct linux_binprm * bprm)
109 {
110         unsigned long *argv,*envp;
111         unsigned long * sp;
112         char * p = (char*)pp;
113         int argc = bprm->argc;
114         int envc = bprm->envc;
115         char uninitialized_var(dummy);
116
117         sp = (unsigned long *) ((-(unsigned long)sizeof(char *))&(unsigned long) p);
118
119         sp -= envc+1;
120         envp = sp;
121         sp -= argc+1;
122         argv = sp;
123
124         flat_stack_align(sp);
125         if (flat_argvp_envp_on_stack()) {
126                 --sp; put_user((unsigned long) envp, sp);
127                 --sp; put_user((unsigned long) argv, sp);
128         }
129
130         put_user(argc,--sp);
131         current->mm->arg_start = (unsigned long) p;
132         while (argc-->0) {
133                 put_user((unsigned long) p, argv++);
134                 do {
135                         get_user(dummy, p); p++;
136                 } while (dummy);
137         }
138         put_user((unsigned long) NULL, argv);
139         current->mm->arg_end = current->mm->env_start = (unsigned long) p;
140         while (envc-->0) {
141                 put_user((unsigned long)p, envp); envp++;
142                 do {
143                         get_user(dummy, p); p++;
144                 } while (dummy);
145         }
146         put_user((unsigned long) NULL, envp);
147         current->mm->env_end = (unsigned long) p;
148         return (unsigned long)sp;
149 }
150
151 /****************************************************************************/
152
153 #ifdef CONFIG_BINFMT_ZFLAT
154
155 #include <linux/zlib.h>
156
157 #define LBUFSIZE        4000
158
159 /* gzip flag byte */
160 #define ASCII_FLAG   0x01 /* bit 0 set: file probably ASCII text */
161 #define CONTINUATION 0x02 /* bit 1 set: continuation of multi-part gzip file */
162 #define EXTRA_FIELD  0x04 /* bit 2 set: extra field present */
163 #define ORIG_NAME    0x08 /* bit 3 set: original file name present */
164 #define COMMENT      0x10 /* bit 4 set: file comment present */
165 #define ENCRYPTED    0x20 /* bit 5 set: file is encrypted */
166 #define RESERVED     0xC0 /* bit 6,7:   reserved */
167
168 static int decompress_exec(
169         struct linux_binprm *bprm,
170         unsigned long offset,
171         char *dst,
172         long len,
173         int fd)
174 {
175         unsigned char *buf;
176         z_stream strm;
177         loff_t fpos;
178         int ret, retval;
179
180         DBG_FLT("decompress_exec(offset=%x,buf=%x,len=%x)\n",(int)offset, (int)dst, (int)len);
181
182         memset(&strm, 0, sizeof(strm));
183         strm.workspace = kmalloc(zlib_inflate_workspacesize(), GFP_KERNEL);
184         if (strm.workspace == NULL) {
185                 DBG_FLT("binfmt_flat: no memory for decompress workspace\n");
186                 return -ENOMEM;
187         }
188         buf = kmalloc(LBUFSIZE, GFP_KERNEL);
189         if (buf == NULL) {
190                 DBG_FLT("binfmt_flat: no memory for read buffer\n");
191                 retval = -ENOMEM;
192                 goto out_free;
193         }
194
195         /* Read in first chunk of data and parse gzip header. */
196         fpos = offset;
197         ret = bprm->file->f_op->read(bprm->file, buf, LBUFSIZE, &fpos);
198
199         strm.next_in = buf;
200         strm.avail_in = ret;
201         strm.total_in = 0;
202
203         retval = -ENOEXEC;
204
205         /* Check minimum size -- gzip header */
206         if (ret < 10) {
207                 DBG_FLT("binfmt_flat: file too small?\n");
208                 goto out_free_buf;
209         }
210
211         /* Check gzip magic number */
212         if ((buf[0] != 037) || ((buf[1] != 0213) && (buf[1] != 0236))) {
213                 DBG_FLT("binfmt_flat: unknown compression magic?\n");
214                 goto out_free_buf;
215         }
216
217         /* Check gzip method */
218         if (buf[2] != 8) {
219                 DBG_FLT("binfmt_flat: unknown compression method?\n");
220                 goto out_free_buf;
221         }
222         /* Check gzip flags */
223         if ((buf[3] & ENCRYPTED) || (buf[3] & CONTINUATION) ||
224             (buf[3] & RESERVED)) {
225                 DBG_FLT("binfmt_flat: unknown flags?\n");
226                 goto out_free_buf;
227         }
228
229         ret = 10;
230         if (buf[3] & EXTRA_FIELD) {
231                 ret += 2 + buf[10] + (buf[11] << 8);
232                 if (unlikely(LBUFSIZE == ret)) {
233                         DBG_FLT("binfmt_flat: buffer overflow (EXTRA)?\n");
234                         goto out_free_buf;
235                 }
236         }
237         if (buf[3] & ORIG_NAME) {
238                 for (; ret < LBUFSIZE && (buf[ret] != 0); ret++)
239                         ;
240                 if (unlikely(LBUFSIZE == ret)) {
241                         DBG_FLT("binfmt_flat: buffer overflow (ORIG_NAME)?\n");
242                         goto out_free_buf;
243                 }
244         }
245         if (buf[3] & COMMENT) {
246                 for (;  ret < LBUFSIZE && (buf[ret] != 0); ret++)
247                         ;
248                 if (unlikely(LBUFSIZE == ret)) {
249                         DBG_FLT("binfmt_flat: buffer overflow (COMMENT)?\n");
250                         goto out_free_buf;
251                 }
252         }
253
254         strm.next_in += ret;
255         strm.avail_in -= ret;
256
257         strm.next_out = dst;
258         strm.avail_out = len;
259         strm.total_out = 0;
260
261         if (zlib_inflateInit2(&strm, -MAX_WBITS) != Z_OK) {
262                 DBG_FLT("binfmt_flat: zlib init failed?\n");
263                 goto out_free_buf;
264         }
265
266         while ((ret = zlib_inflate(&strm, Z_NO_FLUSH)) == Z_OK) {
267                 ret = bprm->file->f_op->read(bprm->file, buf, LBUFSIZE, &fpos);
268                 if (ret <= 0)
269                         break;
270                 if (ret >= (unsigned long) -4096)
271                         break;
272                 len -= ret;
273
274                 strm.next_in = buf;
275                 strm.avail_in = ret;
276                 strm.total_in = 0;
277         }
278
279         if (ret < 0) {
280                 DBG_FLT("binfmt_flat: decompression failed (%d), %s\n",
281                         ret, strm.msg);
282                 goto out_zlib;
283         }
284
285         retval = 0;
286 out_zlib:
287         zlib_inflateEnd(&strm);
288 out_free_buf:
289         kfree(buf);
290 out_free:
291         kfree(strm.workspace);
292         return retval;
293 }
294
295 #endif /* CONFIG_BINFMT_ZFLAT */
296
297 /****************************************************************************/
298
299 static unsigned long
300 calc_reloc(unsigned long r, struct lib_info *p, int curid, int internalp)
301 {
302         unsigned long addr;
303         int id;
304         unsigned long start_brk;
305         unsigned long start_data;
306         unsigned long text_len;
307         unsigned long start_code;
308
309 #ifdef CONFIG_BINFMT_SHARED_FLAT
310         if (r == 0)
311                 id = curid;     /* Relocs of 0 are always self referring */
312         else {
313                 id = (r >> 24) & 0xff;  /* Find ID for this reloc */
314                 r &= 0x00ffffff;        /* Trim ID off here */
315         }
316         if (id >= MAX_SHARED_LIBS) {
317                 printk("BINFMT_FLAT: reference 0x%x to shared library %d",
318                                 (unsigned) r, id);
319                 goto failed;
320         }
321         if (curid != id) {
322                 if (internalp) {
323                         printk("BINFMT_FLAT: reloc address 0x%x not in same module "
324                                         "(%d != %d)", (unsigned) r, curid, id);
325                         goto failed;
326                 } else if ( ! p->lib_list[id].loaded &&
327                                 load_flat_shared_library(id, p) > (unsigned long) -4096) {
328                         printk("BINFMT_FLAT: failed to load library %d", id);
329                         goto failed;
330                 }
331                 /* Check versioning information (i.e. time stamps) */
332                 if (p->lib_list[id].build_date && p->lib_list[curid].build_date &&
333                                 p->lib_list[curid].build_date < p->lib_list[id].build_date) {
334                         printk("BINFMT_FLAT: library %d is younger than %d", id, curid);
335                         goto failed;
336                 }
337         }
338 #else
339         id = 0;
340 #endif
341
342         start_brk = p->lib_list[id].start_brk;
343         start_data = p->lib_list[id].start_data;
344         start_code = p->lib_list[id].start_code;
345         text_len = p->lib_list[id].text_len;
346
347         if (!flat_reloc_valid(r, start_brk - start_data + text_len)) {
348                 printk("BINFMT_FLAT: reloc outside program 0x%x (0 - 0x%x/0x%x)",
349                        (int) r,(int)(start_brk-start_code),(int)text_len);
350                 goto failed;
351         }
352
353         if (r < text_len)                       /* In text segment */
354                 addr = r + start_code;
355         else                                    /* In data segment */
356                 addr = r - text_len + start_data;
357
358         /* Range checked already above so doing the range tests is redundant...*/
359         return(addr);
360
361 failed:
362         printk(", killing %s!\n", current->comm);
363         send_sig(SIGSEGV, current, 0);
364
365         return RELOC_FAILED;
366 }
367
368 /****************************************************************************/
369
370 void old_reloc(unsigned long rl)
371 {
372 #ifdef DEBUG
373         char *segment[] = { "TEXT", "DATA", "BSS", "*UNKNOWN*" };
374 #endif
375         flat_v2_reloc_t r;
376         unsigned long *ptr;
377         
378         r.value = rl;
379 #if defined(CONFIG_COLDFIRE)
380         ptr = (unsigned long *) (current->mm->start_code + r.reloc.offset);
381 #else
382         ptr = (unsigned long *) (current->mm->start_data + r.reloc.offset);
383 #endif
384
385 #ifdef DEBUG
386         printk("Relocation of variable at DATASEG+%x "
387                 "(address %p, currently %x) into segment %s\n",
388                 r.reloc.offset, ptr, (int)*ptr, segment[r.reloc.type]);
389 #endif
390         
391         switch (r.reloc.type) {
392         case OLD_FLAT_RELOC_TYPE_TEXT:
393                 *ptr += current->mm->start_code;
394                 break;
395         case OLD_FLAT_RELOC_TYPE_DATA:
396                 *ptr += current->mm->start_data;
397                 break;
398         case OLD_FLAT_RELOC_TYPE_BSS:
399                 *ptr += current->mm->end_data;
400                 break;
401         default:
402                 printk("BINFMT_FLAT: Unknown relocation type=%x\n", r.reloc.type);
403                 break;
404         }
405
406 #ifdef DEBUG
407         printk("Relocation became %x\n", (int)*ptr);
408 #endif
409 }               
410
411 /****************************************************************************/
412
413 static int load_flat_file(struct linux_binprm * bprm,
414                 struct lib_info *libinfo, int id, unsigned long *extra_stack)
415 {
416         struct flat_hdr * hdr;
417         unsigned long textpos = 0, datapos = 0, result;
418         unsigned long realdatastart = 0;
419         unsigned long text_len, data_len, bss_len, stack_len, flags;
420         unsigned long len, reallen, memp = 0;
421         unsigned long extra, rlim;
422         unsigned long *reloc = 0, *rp;
423         struct inode *inode;
424         int i, rev, relocs = 0;
425         loff_t fpos;
426         unsigned long start_code, end_code;
427         int ret;
428
429         hdr = ((struct flat_hdr *) bprm->buf);          /* exec-header */
430         inode = bprm->file->f_path.dentry->d_inode;
431
432         text_len  = ntohl(hdr->data_start);
433         data_len  = ntohl(hdr->data_end) - ntohl(hdr->data_start);
434         bss_len   = ntohl(hdr->bss_end) - ntohl(hdr->data_end);
435         stack_len = ntohl(hdr->stack_size);
436         if (extra_stack) {
437                 stack_len += *extra_stack;
438                 *extra_stack = stack_len;
439         }
440         relocs    = ntohl(hdr->reloc_count);
441         flags     = ntohl(hdr->flags);
442         rev       = ntohl(hdr->rev);
443
444         if (strncmp(hdr->magic, "bFLT", 4)) {
445                 /*
446                  * Previously, here was a printk to tell people
447                  *   "BINFMT_FLAT: bad header magic".
448                  * But for the kernel which also use ELF FD-PIC format, this
449                  * error message is confusing.
450                  * because a lot of people do not manage to produce good
451                  */
452                 ret = -ENOEXEC;
453                 goto err;
454         }
455
456         if (flags & FLAT_FLAG_KTRACE)
457                 printk("BINFMT_FLAT: Loading file: %s\n", bprm->filename);
458
459         if (rev != FLAT_VERSION && rev != OLD_FLAT_VERSION) {
460                 printk("BINFMT_FLAT: bad flat file version 0x%x (supported "
461                         "0x%lx and 0x%lx)\n",
462                         rev, FLAT_VERSION, OLD_FLAT_VERSION);
463                 ret = -ENOEXEC;
464                 goto err;
465         }
466         
467         /* Don't allow old format executables to use shared libraries */
468         if (rev == OLD_FLAT_VERSION && id != 0) {
469                 printk("BINFMT_FLAT: shared libraries are not available before rev 0x%x\n",
470                                 (int) FLAT_VERSION);
471                 ret = -ENOEXEC;
472                 goto err;
473         }
474
475         /*
476          * fix up the flags for the older format,  there were all kinds
477          * of endian hacks,  this only works for the simple cases
478          */
479         if (rev == OLD_FLAT_VERSION && flat_old_ram_flag(flags))
480                 flags = FLAT_FLAG_RAM;
481
482 #ifndef CONFIG_BINFMT_ZFLAT
483         if (flags & (FLAT_FLAG_GZIP|FLAT_FLAG_GZDATA)) {
484                 printk("Support for ZFLAT executables is not enabled.\n");
485                 ret = -ENOEXEC;
486                 goto err;
487         }
488 #endif
489
490         /*
491          * Check initial limits. This avoids letting people circumvent
492          * size limits imposed on them by creating programs with large
493          * arrays in the data or bss.
494          */
495         rlim = current->signal->rlim[RLIMIT_DATA].rlim_cur;
496         if (rlim >= RLIM_INFINITY)
497                 rlim = ~0;
498         if (data_len + bss_len > rlim) {
499                 ret = -ENOMEM;
500                 goto err;
501         }
502
503         /* Flush all traces of the currently running executable */
504         if (id == 0) {
505                 result = flush_old_exec(bprm);
506                 if (result) {
507                         ret = result;
508                         goto err;
509                 }
510
511                 /* OK, This is the point of no return */
512                 set_personality(PER_LINUX_32BIT);
513         }
514
515         /*
516          * calculate the extra space we need to map in
517          */
518         extra = max_t(unsigned long, bss_len + stack_len,
519                         relocs * sizeof(unsigned long));
520
521         /*
522          * there are a couple of cases here,  the separate code/data
523          * case,  and then the fully copied to RAM case which lumps
524          * it all together.
525          */
526         if ((flags & (FLAT_FLAG_RAM|FLAT_FLAG_GZIP)) == 0) {
527                 /*
528                  * this should give us a ROM ptr,  but if it doesn't we don't
529                  * really care
530                  */
531                 DBG_FLT("BINFMT_FLAT: ROM mapping of file (we hope)\n");
532
533                 down_write(&current->mm->mmap_sem);
534                 textpos = do_mmap(bprm->file, 0, text_len, PROT_READ|PROT_EXEC, MAP_PRIVATE, 0);
535                 up_write(&current->mm->mmap_sem);
536                 if (!textpos  || textpos >= (unsigned long) -4096) {
537                         if (!textpos)
538                                 textpos = (unsigned long) -ENOMEM;
539                         printk("Unable to mmap process text, errno %d\n", (int)-textpos);
540                         ret = textpos;
541                         goto err;
542                 }
543
544                 len = data_len + extra + MAX_SHARED_LIBS * sizeof(unsigned long);
545                 down_write(&current->mm->mmap_sem);
546                 realdatastart = do_mmap(0, 0, len,
547                         PROT_READ|PROT_WRITE|PROT_EXEC, MAP_PRIVATE, 0);
548                 /* Remap to use all availabe slack region space */
549                 if (realdatastart && (realdatastart < (unsigned long)-4096)) {
550                         reallen = ksize((void *)realdatastart);
551                         if (reallen > len) {
552                                 realdatastart = do_mremap(realdatastart, len,
553                                         reallen, MREMAP_FIXED, realdatastart);
554                         }
555                 }
556                 up_write(&current->mm->mmap_sem);
557
558                 if (realdatastart == 0 || realdatastart >= (unsigned long)-4096) {
559                         if (!realdatastart)
560                                 realdatastart = (unsigned long) -ENOMEM;
561                         printk("Unable to allocate RAM for process data, errno %d\n",
562                                         (int)-realdatastart);
563                         do_munmap(current->mm, textpos, text_len);
564                         ret = realdatastart;
565                         goto err;
566                 }
567                 datapos = realdatastart + MAX_SHARED_LIBS * sizeof(unsigned long);
568
569                 DBG_FLT("BINFMT_FLAT: Allocated data+bss+stack (%d bytes): %x\n",
570                                 (int)(data_len + bss_len + stack_len), (int)datapos);
571
572                 fpos = ntohl(hdr->data_start);
573 #ifdef CONFIG_BINFMT_ZFLAT
574                 if (flags & FLAT_FLAG_GZDATA) {
575                         result = decompress_exec(bprm, fpos, (char *) datapos, 
576                                                  data_len + (relocs * sizeof(unsigned long)), 0);
577                 } else
578 #endif
579                 {
580                         result = bprm->file->f_op->read(bprm->file, (char *) datapos,
581                                         data_len + (relocs * sizeof(unsigned long)), &fpos);
582                 }
583                 if (result >= (unsigned long)-4096) {
584                         printk("Unable to read data+bss, errno %d\n", (int)-result);
585                         do_munmap(current->mm, textpos, text_len);
586                         do_munmap(current->mm, realdatastart, data_len + extra);
587                         ret = result;
588                         goto err;
589                 }
590
591                 reloc = (unsigned long *) (datapos+(ntohl(hdr->reloc_start)-text_len));
592                 memp = realdatastart;
593
594         } else {
595
596                 len = text_len + data_len + extra + MAX_SHARED_LIBS * sizeof(unsigned long);
597                 down_write(&current->mm->mmap_sem);
598                 textpos = do_mmap(0, 0, len,
599                         PROT_READ | PROT_EXEC | PROT_WRITE, MAP_PRIVATE, 0);
600                 /* Remap to use all availabe slack region space */
601                 if (textpos && (textpos < (unsigned long) -4096)) {
602                         reallen = ksize((void *)textpos);
603                         if (reallen > len) {
604                                 textpos = do_mremap(textpos, len, reallen,
605                                         MREMAP_FIXED, textpos);
606                         }
607                 }
608                 up_write(&current->mm->mmap_sem);
609
610                 if (!textpos  || textpos >= (unsigned long) -4096) {
611                         if (!textpos)
612                                 textpos = (unsigned long) -ENOMEM;
613                         printk("Unable to allocate RAM for process text/data, errno %d\n",
614                                         (int)-textpos);
615                         ret = textpos;
616                         goto err;
617                 }
618
619                 realdatastart = textpos + ntohl(hdr->data_start);
620                 datapos = realdatastart + MAX_SHARED_LIBS * sizeof(unsigned long);
621                 reloc = (unsigned long *) (textpos + ntohl(hdr->reloc_start) +
622                                 MAX_SHARED_LIBS * sizeof(unsigned long));
623                 memp = textpos;
624
625 #ifdef CONFIG_BINFMT_ZFLAT
626                 /*
627                  * load it all in and treat it like a RAM load from now on
628                  */
629                 if (flags & FLAT_FLAG_GZIP) {
630                         result = decompress_exec(bprm, sizeof (struct flat_hdr),
631                                          (((char *) textpos) + sizeof (struct flat_hdr)),
632                                          (text_len + data_len + (relocs * sizeof(unsigned long))
633                                                   - sizeof (struct flat_hdr)),
634                                          0);
635                         memmove((void *) datapos, (void *) realdatastart,
636                                         data_len + (relocs * sizeof(unsigned long)));
637                 } else if (flags & FLAT_FLAG_GZDATA) {
638                         fpos = 0;
639                         result = bprm->file->f_op->read(bprm->file,
640                                         (char *) textpos, text_len, &fpos);
641                         if (result < (unsigned long) -4096)
642                                 result = decompress_exec(bprm, text_len, (char *) datapos,
643                                                  data_len + (relocs * sizeof(unsigned long)), 0);
644                 }
645                 else
646 #endif
647                 {
648                         fpos = 0;
649                         result = bprm->file->f_op->read(bprm->file,
650                                         (char *) textpos, text_len, &fpos);
651                         if (result < (unsigned long) -4096) {
652                                 fpos = ntohl(hdr->data_start);
653                                 result = bprm->file->f_op->read(bprm->file, (char *) datapos,
654                                         data_len + (relocs * sizeof(unsigned long)), &fpos);
655                         }
656                 }
657                 if (result >= (unsigned long)-4096) {
658                         printk("Unable to read code+data+bss, errno %d\n",(int)-result);
659                         do_munmap(current->mm, textpos, text_len + data_len + extra +
660                                 MAX_SHARED_LIBS * sizeof(unsigned long));
661                         ret = result;
662                         goto err;
663                 }
664         }
665
666         if (flags & FLAT_FLAG_KTRACE)
667                 printk("Mapping is %x, Entry point is %x, data_start is %x\n",
668                         (int)textpos, 0x00ffffff&ntohl(hdr->entry), ntohl(hdr->data_start));
669
670         /* The main program needs a little extra setup in the task structure */
671         start_code = textpos + sizeof (struct flat_hdr);
672         end_code = textpos + text_len;
673         if (id == 0) {
674                 current->mm->start_code = start_code;
675                 current->mm->end_code = end_code;
676                 current->mm->start_data = datapos;
677                 current->mm->end_data = datapos + data_len;
678                 /*
679                  * set up the brk stuff, uses any slack left in data/bss/stack
680                  * allocation.  We put the brk after the bss (between the bss
681                  * and stack) like other platforms.
682                  */
683                 current->mm->start_brk = datapos + data_len + bss_len;
684                 current->mm->brk = (current->mm->start_brk + 3) & ~3;
685                 current->mm->context.end_brk = memp + ksize((void *) memp) - stack_len;
686         }
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.
713          * The first is the GOT which resides at the begining of the data segment
714          * 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);
725                                 if (addr == RELOC_FAILED) {
726                                         ret = -ENOEXEC;
727                                         goto err;
728                                 }
729                                 *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) {
746                 unsigned long persistent = 0;
747                 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]);
754                         if (flat_set_persistent (relval, &persistent))
755                                 continue;
756                         addr = flat_get_relocate_addr(relval);
757                         rp = (unsigned long *) calc_reloc(addr, libinfo, id, 1);
758                         if (rp == (unsigned long *)RELOC_FAILED) {
759                                 ret = -ENOEXEC;
760                                 goto err;
761                         }
762
763                         /* Get the pointer's value.  */
764                         addr = flat_get_addr_from_rp(rp, relval, flags,
765                                                         &persistent);
766                         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);
774                                 if (addr == RELOC_FAILED) {
775                                         ret = -ENOEXEC;
776                                         goto err;
777                                 }
778
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 + 
792                         (memp + ksize((void *) memp) - stack_len -      /* end brk */
793                         libinfo->lib_list[id].start_brk) +              /* start brk */
794                         stack_len);
795
796         return 0;
797 err:
798         return ret;
799 }
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
810 static 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
816         /* Create the file name */
817         sprintf(buf, "/lib/lib%d.so", id);
818
819         /* Open the file up */
820         bprm.filename = buf;
821         bprm.file = open_exec(bprm.filename);
822         res = PTR_ERR(bprm.file);
823         if (IS_ERR(bprm.file))
824                 return res;
825
826         res = prepare_binprm(&bprm);
827
828         if (res <= (unsigned long)-4096)
829                 res = load_flat_file(&bprm, libs, id, NULL);
830         if (bprm.file) {
831                 allow_write_access(bprm.file);
832                 fput(bprm.file);
833                 bprm.file = NULL;
834         }
835         return(res);
836 }
837
838 #endif /* CONFIG_BINFMT_SHARED_FLAT */
839 /****************************************************************************/
840
841 /*
842  * These are the functions used to load flat style executables and shared
843  * libraries.  There is no binary dependent code anywhere else.
844  */
845
846 static int load_flat_binary(struct linux_binprm * bprm, struct pt_regs * regs)
847 {
848         struct lib_info libinfo;
849         unsigned long p = bprm->p;
850         unsigned long stack_len;
851         unsigned long start_addr;
852         unsigned long *sp;
853         int res;
854         int i, j;
855
856         memset(&libinfo, 0, sizeof(libinfo));
857         /*
858          * We have to add the size of our arguments to our stack size
859          * otherwise it's too easy for users to create stack overflows
860          * by passing in a huge argument list.  And yes,  we have to be
861          * pedantic and include space for the argv/envp array as it may have
862          * a lot of entries.
863          */
864 #define TOP_OF_ARGS (PAGE_SIZE * MAX_ARG_PAGES - sizeof(void *))
865         stack_len = TOP_OF_ARGS - bprm->p;             /* the strings */
866         stack_len += (bprm->argc + 1) * sizeof(char *); /* the argv array */
867         stack_len += (bprm->envc + 1) * sizeof(char *); /* the envp array */
868
869         
870         res = load_flat_file(bprm, &libinfo, 0, &stack_len);
871         if (res > (unsigned long)-4096)
872                 return res;
873         
874         /* Update data segment pointers for all libraries */
875         for (i=0; i<MAX_SHARED_LIBS; i++)
876                 if (libinfo.lib_list[i].loaded)
877                         for (j=0; j<MAX_SHARED_LIBS; j++)
878                                 (-(j+1))[(unsigned long *)(libinfo.lib_list[i].start_data)] =
879                                         (libinfo.lib_list[j].loaded)?
880                                                 libinfo.lib_list[j].start_data:UNLOADED_LIB;
881
882         compute_creds(bprm);
883         current->flags &= ~PF_FORKNOEXEC;
884
885         set_binfmt(&flat_format);
886
887         p = ((current->mm->context.end_brk + stack_len + 3) & ~3) - 4;
888         DBG_FLT("p=%x\n", (int)p);
889
890         /* copy the arg pages onto the stack, this could be more efficient :-) */
891         for (i = TOP_OF_ARGS - 1; i >= bprm->p; i--)
892                 * (char *) --p =
893                         ((char *) page_address(bprm->page[i/PAGE_SIZE]))[i % PAGE_SIZE];
894
895         sp = (unsigned long *) create_flat_tables(p, bprm);
896         
897         /* Fake some return addresses to ensure the call chain will
898          * initialise library in order for us.  We are required to call
899          * lib 1 first, then 2, ... and finally the main program (id 0).
900          */
901         start_addr = libinfo.lib_list[0].entry;
902
903 #ifdef CONFIG_BINFMT_SHARED_FLAT
904         for (i = MAX_SHARED_LIBS-1; i>0; i--) {
905                 if (libinfo.lib_list[i].loaded) {
906                         /* Push previos first to call address */
907                         --sp;   put_user(start_addr, sp);
908                         start_addr = libinfo.lib_list[i].entry;
909                 }
910         }
911 #endif
912         
913         /* Stash our initial stack pointer into the mm structure */
914         current->mm->start_stack = (unsigned long )sp;
915
916         
917         DBG_FLT("start_thread(regs=0x%x, entry=0x%x, start_stack=0x%x)\n",
918                 (int)regs, (int)start_addr, (int)current->mm->start_stack);
919         
920         start_thread(regs, start_addr, current->mm->start_stack);
921
922         if (current->ptrace & PT_PTRACED)
923                 send_sig(SIGTRAP, current, 0);
924
925         return 0;
926 }
927
928 /****************************************************************************/
929
930 static int __init init_flat_binfmt(void)
931 {
932         return register_binfmt(&flat_format);
933 }
934
935 static void __exit exit_flat_binfmt(void)
936 {
937         unregister_binfmt(&flat_format);
938 }
939
940 /****************************************************************************/
941
942 core_initcall(init_flat_binfmt);
943 module_exit(exit_flat_binfmt);
944
945 /****************************************************************************/