Contents of /alx-src/tags/kernel26-2.6.12-alx-r9/fs/binfmt_misc.c
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Wed Mar 4 11:03:09 2009 UTC (15 years, 6 months ago) by niro
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Wed Mar 4 11:03:09 2009 UTC (15 years, 6 months ago) by niro
File MIME type: text/plain
File size: 16018 byte(s)
Tag kernel26-2.6.12-alx-r9
1 | /* |
2 | * binfmt_misc.c |
3 | * |
4 | * Copyright (C) 1997 Richard Günther |
5 | * |
6 | * binfmt_misc detects binaries via a magic or filename extension and invokes |
7 | * a specified wrapper. This should obsolete binfmt_java, binfmt_em86 and |
8 | * binfmt_mz. |
9 | * |
10 | * 1997-04-25 first version |
11 | * [...] |
12 | * 1997-05-19 cleanup |
13 | * 1997-06-26 hpa: pass the real filename rather than argv[0] |
14 | * 1997-06-30 minor cleanup |
15 | * 1997-08-09 removed extension stripping, locking cleanup |
16 | * 2001-02-28 AV: rewritten into something that resembles C. Original didn't. |
17 | */ |
18 | |
19 | #include <linux/module.h> |
20 | #include <linux/init.h> |
21 | |
22 | #include <linux/binfmts.h> |
23 | #include <linux/slab.h> |
24 | #include <linux/ctype.h> |
25 | #include <linux/file.h> |
26 | #include <linux/pagemap.h> |
27 | #include <linux/namei.h> |
28 | #include <linux/mount.h> |
29 | #include <linux/syscalls.h> |
30 | |
31 | #include <asm/uaccess.h> |
32 | |
33 | enum { |
34 | VERBOSE_STATUS = 1 /* make it zero to save 400 bytes kernel memory */ |
35 | }; |
36 | |
37 | static LIST_HEAD(entries); |
38 | static int enabled = 1; |
39 | |
40 | enum {Enabled, Magic}; |
41 | #define MISC_FMT_PRESERVE_ARGV0 (1<<31) |
42 | #define MISC_FMT_OPEN_BINARY (1<<30) |
43 | #define MISC_FMT_CREDENTIALS (1<<29) |
44 | |
45 | typedef struct { |
46 | struct list_head list; |
47 | unsigned long flags; /* type, status, etc. */ |
48 | int offset; /* offset of magic */ |
49 | int size; /* size of magic/mask */ |
50 | char *magic; /* magic or filename extension */ |
51 | char *mask; /* mask, NULL for exact match */ |
52 | char *interpreter; /* filename of interpreter */ |
53 | char *name; |
54 | struct dentry *dentry; |
55 | } Node; |
56 | |
57 | static DEFINE_RWLOCK(entries_lock); |
58 | static struct vfsmount *bm_mnt; |
59 | static int entry_count; |
60 | |
61 | /* |
62 | * Check if we support the binfmt |
63 | * if we do, return the node, else NULL |
64 | * locking is done in load_misc_binary |
65 | */ |
66 | static Node *check_file(struct linux_binprm *bprm) |
67 | { |
68 | char *p = strrchr(bprm->interp, '.'); |
69 | struct list_head *l; |
70 | |
71 | list_for_each(l, &entries) { |
72 | Node *e = list_entry(l, Node, list); |
73 | char *s; |
74 | int j; |
75 | |
76 | if (!test_bit(Enabled, &e->flags)) |
77 | continue; |
78 | |
79 | if (!test_bit(Magic, &e->flags)) { |
80 | if (p && !strcmp(e->magic, p + 1)) |
81 | return e; |
82 | continue; |
83 | } |
84 | |
85 | s = bprm->buf + e->offset; |
86 | if (e->mask) { |
87 | for (j = 0; j < e->size; j++) |
88 | if ((*s++ ^ e->magic[j]) & e->mask[j]) |
89 | break; |
90 | } else { |
91 | for (j = 0; j < e->size; j++) |
92 | if ((*s++ ^ e->magic[j])) |
93 | break; |
94 | } |
95 | if (j == e->size) |
96 | return e; |
97 | } |
98 | return NULL; |
99 | } |
100 | |
101 | /* |
102 | * the loader itself |
103 | */ |
104 | static int load_misc_binary(struct linux_binprm *bprm, struct pt_regs *regs) |
105 | { |
106 | Node *fmt; |
107 | struct file * interp_file = NULL; |
108 | char iname[BINPRM_BUF_SIZE]; |
109 | char *iname_addr = iname; |
110 | int retval; |
111 | int fd_binary = -1; |
112 | struct files_struct *files = NULL; |
113 | |
114 | retval = -ENOEXEC; |
115 | if (!enabled) |
116 | goto _ret; |
117 | |
118 | /* to keep locking time low, we copy the interpreter string */ |
119 | read_lock(&entries_lock); |
120 | fmt = check_file(bprm); |
121 | if (fmt) |
122 | strlcpy(iname, fmt->interpreter, BINPRM_BUF_SIZE); |
123 | read_unlock(&entries_lock); |
124 | if (!fmt) |
125 | goto _ret; |
126 | |
127 | if (!(fmt->flags & MISC_FMT_PRESERVE_ARGV0)) { |
128 | remove_arg_zero(bprm); |
129 | } |
130 | |
131 | if (fmt->flags & MISC_FMT_OPEN_BINARY) { |
132 | |
133 | files = current->files; |
134 | retval = unshare_files(); |
135 | if (retval < 0) |
136 | goto _ret; |
137 | if (files == current->files) { |
138 | put_files_struct(files); |
139 | files = NULL; |
140 | } |
141 | /* if the binary should be opened on behalf of the |
142 | * interpreter than keep it open and assign descriptor |
143 | * to it */ |
144 | fd_binary = get_unused_fd(); |
145 | if (fd_binary < 0) { |
146 | retval = fd_binary; |
147 | goto _unshare; |
148 | } |
149 | fd_install(fd_binary, bprm->file); |
150 | |
151 | /* if the binary is not readable than enforce mm->dumpable=0 |
152 | regardless of the interpreter's permissions */ |
153 | if (permission(bprm->file->f_dentry->d_inode, MAY_READ, NULL)) |
154 | bprm->interp_flags |= BINPRM_FLAGS_ENFORCE_NONDUMP; |
155 | |
156 | allow_write_access(bprm->file); |
157 | bprm->file = NULL; |
158 | |
159 | /* mark the bprm that fd should be passed to interp */ |
160 | bprm->interp_flags |= BINPRM_FLAGS_EXECFD; |
161 | bprm->interp_data = fd_binary; |
162 | |
163 | } else { |
164 | allow_write_access(bprm->file); |
165 | fput(bprm->file); |
166 | bprm->file = NULL; |
167 | } |
168 | /* make argv[1] be the path to the binary */ |
169 | retval = copy_strings_kernel (1, &bprm->interp, bprm); |
170 | if (retval < 0) |
171 | goto _error; |
172 | bprm->argc++; |
173 | |
174 | /* add the interp as argv[0] */ |
175 | retval = copy_strings_kernel (1, &iname_addr, bprm); |
176 | if (retval < 0) |
177 | goto _error; |
178 | bprm->argc ++; |
179 | |
180 | bprm->interp = iname; /* for binfmt_script */ |
181 | |
182 | interp_file = open_exec (iname); |
183 | retval = PTR_ERR (interp_file); |
184 | if (IS_ERR (interp_file)) |
185 | goto _error; |
186 | |
187 | bprm->file = interp_file; |
188 | if (fmt->flags & MISC_FMT_CREDENTIALS) { |
189 | /* |
190 | * No need to call prepare_binprm(), it's already been |
191 | * done. bprm->buf is stale, update from interp_file. |
192 | */ |
193 | memset(bprm->buf, 0, BINPRM_BUF_SIZE); |
194 | retval = kernel_read(bprm->file, 0, bprm->buf, BINPRM_BUF_SIZE); |
195 | } else |
196 | retval = prepare_binprm (bprm); |
197 | |
198 | if (retval < 0) |
199 | goto _error; |
200 | |
201 | retval = search_binary_handler (bprm, regs); |
202 | if (retval < 0) |
203 | goto _error; |
204 | |
205 | if (files) { |
206 | steal_locks(files); |
207 | put_files_struct(files); |
208 | files = NULL; |
209 | } |
210 | _ret: |
211 | return retval; |
212 | _error: |
213 | if (fd_binary > 0) |
214 | sys_close(fd_binary); |
215 | bprm->interp_flags = 0; |
216 | bprm->interp_data = 0; |
217 | _unshare: |
218 | if (files) { |
219 | put_files_struct(current->files); |
220 | current->files = files; |
221 | } |
222 | goto _ret; |
223 | } |
224 | |
225 | /* Command parsers */ |
226 | |
227 | /* |
228 | * parses and copies one argument enclosed in del from *sp to *dp, |
229 | * recognising the \x special. |
230 | * returns pointer to the copied argument or NULL in case of an |
231 | * error (and sets err) or null argument length. |
232 | */ |
233 | static char *scanarg(char *s, char del) |
234 | { |
235 | char c; |
236 | |
237 | while ((c = *s++) != del) { |
238 | if (c == '\\' && *s == 'x') { |
239 | s++; |
240 | if (!isxdigit(*s++)) |
241 | return NULL; |
242 | if (!isxdigit(*s++)) |
243 | return NULL; |
244 | } |
245 | } |
246 | return s; |
247 | } |
248 | |
249 | static int unquote(char *from) |
250 | { |
251 | char c = 0, *s = from, *p = from; |
252 | |
253 | while ((c = *s++) != '\0') { |
254 | if (c == '\\' && *s == 'x') { |
255 | s++; |
256 | c = toupper(*s++); |
257 | *p = (c - (isdigit(c) ? '0' : 'A' - 10)) << 4; |
258 | c = toupper(*s++); |
259 | *p++ |= c - (isdigit(c) ? '0' : 'A' - 10); |
260 | continue; |
261 | } |
262 | *p++ = c; |
263 | } |
264 | return p - from; |
265 | } |
266 | |
267 | static inline char * check_special_flags (char * sfs, Node * e) |
268 | { |
269 | char * p = sfs; |
270 | int cont = 1; |
271 | |
272 | /* special flags */ |
273 | while (cont) { |
274 | switch (*p) { |
275 | case 'P': |
276 | p++; |
277 | e->flags |= MISC_FMT_PRESERVE_ARGV0; |
278 | break; |
279 | case 'O': |
280 | p++; |
281 | e->flags |= MISC_FMT_OPEN_BINARY; |
282 | break; |
283 | case 'C': |
284 | p++; |
285 | /* this flags also implies the |
286 | open-binary flag */ |
287 | e->flags |= (MISC_FMT_CREDENTIALS | |
288 | MISC_FMT_OPEN_BINARY); |
289 | break; |
290 | default: |
291 | cont = 0; |
292 | } |
293 | } |
294 | |
295 | return p; |
296 | } |
297 | /* |
298 | * This registers a new binary format, it recognises the syntax |
299 | * ':name:type:offset:magic:mask:interpreter:flags' |
300 | * where the ':' is the IFS, that can be chosen with the first char |
301 | */ |
302 | static Node *create_entry(const char __user *buffer, size_t count) |
303 | { |
304 | Node *e; |
305 | int memsize, err; |
306 | char *buf, *p; |
307 | char del; |
308 | |
309 | /* some sanity checks */ |
310 | err = -EINVAL; |
311 | if ((count < 11) || (count > 256)) |
312 | goto out; |
313 | |
314 | err = -ENOMEM; |
315 | memsize = sizeof(Node) + count + 8; |
316 | e = (Node *) kmalloc(memsize, GFP_USER); |
317 | if (!e) |
318 | goto out; |
319 | |
320 | p = buf = (char *)e + sizeof(Node); |
321 | |
322 | memset(e, 0, sizeof(Node)); |
323 | if (copy_from_user(buf, buffer, count)) |
324 | goto Efault; |
325 | |
326 | del = *p++; /* delimeter */ |
327 | |
328 | memset(buf+count, del, 8); |
329 | |
330 | e->name = p; |
331 | p = strchr(p, del); |
332 | if (!p) |
333 | goto Einval; |
334 | *p++ = '\0'; |
335 | if (!e->name[0] || |
336 | !strcmp(e->name, ".") || |
337 | !strcmp(e->name, "..") || |
338 | strchr(e->name, '/')) |
339 | goto Einval; |
340 | switch (*p++) { |
341 | case 'E': e->flags = 1<<Enabled; break; |
342 | case 'M': e->flags = (1<<Enabled) | (1<<Magic); break; |
343 | default: goto Einval; |
344 | } |
345 | if (*p++ != del) |
346 | goto Einval; |
347 | if (test_bit(Magic, &e->flags)) { |
348 | char *s = strchr(p, del); |
349 | if (!s) |
350 | goto Einval; |
351 | *s++ = '\0'; |
352 | e->offset = simple_strtoul(p, &p, 10); |
353 | if (*p++) |
354 | goto Einval; |
355 | e->magic = p; |
356 | p = scanarg(p, del); |
357 | if (!p) |
358 | goto Einval; |
359 | p[-1] = '\0'; |
360 | if (!e->magic[0]) |
361 | goto Einval; |
362 | e->mask = p; |
363 | p = scanarg(p, del); |
364 | if (!p) |
365 | goto Einval; |
366 | p[-1] = '\0'; |
367 | if (!e->mask[0]) |
368 | e->mask = NULL; |
369 | e->size = unquote(e->magic); |
370 | if (e->mask && unquote(e->mask) != e->size) |
371 | goto Einval; |
372 | if (e->size + e->offset > BINPRM_BUF_SIZE) |
373 | goto Einval; |
374 | } else { |
375 | p = strchr(p, del); |
376 | if (!p) |
377 | goto Einval; |
378 | *p++ = '\0'; |
379 | e->magic = p; |
380 | p = strchr(p, del); |
381 | if (!p) |
382 | goto Einval; |
383 | *p++ = '\0'; |
384 | if (!e->magic[0] || strchr(e->magic, '/')) |
385 | goto Einval; |
386 | p = strchr(p, del); |
387 | if (!p) |
388 | goto Einval; |
389 | *p++ = '\0'; |
390 | } |
391 | e->interpreter = p; |
392 | p = strchr(p, del); |
393 | if (!p) |
394 | goto Einval; |
395 | *p++ = '\0'; |
396 | if (!e->interpreter[0]) |
397 | goto Einval; |
398 | |
399 | |
400 | p = check_special_flags (p, e); |
401 | |
402 | if (*p == '\n') |
403 | p++; |
404 | if (p != buf + count) |
405 | goto Einval; |
406 | return e; |
407 | |
408 | out: |
409 | return ERR_PTR(err); |
410 | |
411 | Efault: |
412 | kfree(e); |
413 | return ERR_PTR(-EFAULT); |
414 | Einval: |
415 | kfree(e); |
416 | return ERR_PTR(-EINVAL); |
417 | } |
418 | |
419 | /* |
420 | * Set status of entry/binfmt_misc: |
421 | * '1' enables, '0' disables and '-1' clears entry/binfmt_misc |
422 | */ |
423 | static int parse_command(const char __user *buffer, size_t count) |
424 | { |
425 | char s[4]; |
426 | |
427 | if (!count) |
428 | return 0; |
429 | if (count > 3) |
430 | return -EINVAL; |
431 | if (copy_from_user(s, buffer, count)) |
432 | return -EFAULT; |
433 | if (s[count-1] == '\n') |
434 | count--; |
435 | if (count == 1 && s[0] == '0') |
436 | return 1; |
437 | if (count == 1 && s[0] == '1') |
438 | return 2; |
439 | if (count == 2 && s[0] == '-' && s[1] == '1') |
440 | return 3; |
441 | return -EINVAL; |
442 | } |
443 | |
444 | /* generic stuff */ |
445 | |
446 | static void entry_status(Node *e, char *page) |
447 | { |
448 | char *dp; |
449 | char *status = "disabled"; |
450 | const char * flags = "flags: "; |
451 | |
452 | if (test_bit(Enabled, &e->flags)) |
453 | status = "enabled"; |
454 | |
455 | if (!VERBOSE_STATUS) { |
456 | sprintf(page, "%s\n", status); |
457 | return; |
458 | } |
459 | |
460 | sprintf(page, "%s\ninterpreter %s\n", status, e->interpreter); |
461 | dp = page + strlen(page); |
462 | |
463 | /* print the special flags */ |
464 | sprintf (dp, "%s", flags); |
465 | dp += strlen (flags); |
466 | if (e->flags & MISC_FMT_PRESERVE_ARGV0) { |
467 | *dp ++ = 'P'; |
468 | } |
469 | if (e->flags & MISC_FMT_OPEN_BINARY) { |
470 | *dp ++ = 'O'; |
471 | } |
472 | if (e->flags & MISC_FMT_CREDENTIALS) { |
473 | *dp ++ = 'C'; |
474 | } |
475 | *dp ++ = '\n'; |
476 | |
477 | |
478 | if (!test_bit(Magic, &e->flags)) { |
479 | sprintf(dp, "extension .%s\n", e->magic); |
480 | } else { |
481 | int i; |
482 | |
483 | sprintf(dp, "offset %i\nmagic ", e->offset); |
484 | dp = page + strlen(page); |
485 | for (i = 0; i < e->size; i++) { |
486 | sprintf(dp, "%02x", 0xff & (int) (e->magic[i])); |
487 | dp += 2; |
488 | } |
489 | if (e->mask) { |
490 | sprintf(dp, "\nmask "); |
491 | dp += 6; |
492 | for (i = 0; i < e->size; i++) { |
493 | sprintf(dp, "%02x", 0xff & (int) (e->mask[i])); |
494 | dp += 2; |
495 | } |
496 | } |
497 | *dp++ = '\n'; |
498 | *dp = '\0'; |
499 | } |
500 | } |
501 | |
502 | static struct inode *bm_get_inode(struct super_block *sb, int mode) |
503 | { |
504 | struct inode * inode = new_inode(sb); |
505 | |
506 | if (inode) { |
507 | inode->i_mode = mode; |
508 | inode->i_uid = 0; |
509 | inode->i_gid = 0; |
510 | inode->i_blksize = PAGE_CACHE_SIZE; |
511 | inode->i_blocks = 0; |
512 | inode->i_atime = inode->i_mtime = inode->i_ctime = |
513 | current_fs_time(inode->i_sb); |
514 | } |
515 | return inode; |
516 | } |
517 | |
518 | static void bm_clear_inode(struct inode *inode) |
519 | { |
520 | kfree(inode->u.generic_ip); |
521 | } |
522 | |
523 | static void kill_node(Node *e) |
524 | { |
525 | struct dentry *dentry; |
526 | |
527 | write_lock(&entries_lock); |
528 | dentry = e->dentry; |
529 | if (dentry) { |
530 | list_del_init(&e->list); |
531 | e->dentry = NULL; |
532 | } |
533 | write_unlock(&entries_lock); |
534 | |
535 | if (dentry) { |
536 | dentry->d_inode->i_nlink--; |
537 | d_drop(dentry); |
538 | dput(dentry); |
539 | simple_release_fs(&bm_mnt, &entry_count); |
540 | } |
541 | } |
542 | |
543 | /* /<entry> */ |
544 | |
545 | static ssize_t |
546 | bm_entry_read(struct file * file, char __user * buf, size_t nbytes, loff_t *ppos) |
547 | { |
548 | Node *e = file->f_dentry->d_inode->u.generic_ip; |
549 | loff_t pos = *ppos; |
550 | ssize_t res; |
551 | char *page; |
552 | int len; |
553 | |
554 | if (!(page = (char*) __get_free_page(GFP_KERNEL))) |
555 | return -ENOMEM; |
556 | |
557 | entry_status(e, page); |
558 | len = strlen(page); |
559 | |
560 | res = -EINVAL; |
561 | if (pos < 0) |
562 | goto out; |
563 | res = 0; |
564 | if (pos >= len) |
565 | goto out; |
566 | if (len < pos + nbytes) |
567 | nbytes = len - pos; |
568 | res = -EFAULT; |
569 | if (copy_to_user(buf, page + pos, nbytes)) |
570 | goto out; |
571 | *ppos = pos + nbytes; |
572 | res = nbytes; |
573 | out: |
574 | free_page((unsigned long) page); |
575 | return res; |
576 | } |
577 | |
578 | static ssize_t bm_entry_write(struct file *file, const char __user *buffer, |
579 | size_t count, loff_t *ppos) |
580 | { |
581 | struct dentry *root; |
582 | Node *e = file->f_dentry->d_inode->u.generic_ip; |
583 | int res = parse_command(buffer, count); |
584 | |
585 | switch (res) { |
586 | case 1: clear_bit(Enabled, &e->flags); |
587 | break; |
588 | case 2: set_bit(Enabled, &e->flags); |
589 | break; |
590 | case 3: root = dget(file->f_vfsmnt->mnt_sb->s_root); |
591 | down(&root->d_inode->i_sem); |
592 | |
593 | kill_node(e); |
594 | |
595 | up(&root->d_inode->i_sem); |
596 | dput(root); |
597 | break; |
598 | default: return res; |
599 | } |
600 | return count; |
601 | } |
602 | |
603 | static struct file_operations bm_entry_operations = { |
604 | .read = bm_entry_read, |
605 | .write = bm_entry_write, |
606 | }; |
607 | |
608 | /* /register */ |
609 | |
610 | static ssize_t bm_register_write(struct file *file, const char __user *buffer, |
611 | size_t count, loff_t *ppos) |
612 | { |
613 | Node *e; |
614 | struct inode *inode; |
615 | struct dentry *root, *dentry; |
616 | struct super_block *sb = file->f_vfsmnt->mnt_sb; |
617 | int err = 0; |
618 | |
619 | e = create_entry(buffer, count); |
620 | |
621 | if (IS_ERR(e)) |
622 | return PTR_ERR(e); |
623 | |
624 | root = dget(sb->s_root); |
625 | down(&root->d_inode->i_sem); |
626 | dentry = lookup_one_len(e->name, root, strlen(e->name)); |
627 | err = PTR_ERR(dentry); |
628 | if (IS_ERR(dentry)) |
629 | goto out; |
630 | |
631 | err = -EEXIST; |
632 | if (dentry->d_inode) |
633 | goto out2; |
634 | |
635 | inode = bm_get_inode(sb, S_IFREG | 0644); |
636 | |
637 | err = -ENOMEM; |
638 | if (!inode) |
639 | goto out2; |
640 | |
641 | err = simple_pin_fs("binfmt_misc", &bm_mnt, &entry_count); |
642 | if (err) { |
643 | iput(inode); |
644 | inode = NULL; |
645 | goto out2; |
646 | } |
647 | |
648 | e->dentry = dget(dentry); |
649 | inode->u.generic_ip = e; |
650 | inode->i_fop = &bm_entry_operations; |
651 | |
652 | d_instantiate(dentry, inode); |
653 | write_lock(&entries_lock); |
654 | list_add(&e->list, &entries); |
655 | write_unlock(&entries_lock); |
656 | |
657 | err = 0; |
658 | out2: |
659 | dput(dentry); |
660 | out: |
661 | up(&root->d_inode->i_sem); |
662 | dput(root); |
663 | |
664 | if (err) { |
665 | kfree(e); |
666 | return -EINVAL; |
667 | } |
668 | return count; |
669 | } |
670 | |
671 | static struct file_operations bm_register_operations = { |
672 | .write = bm_register_write, |
673 | }; |
674 | |
675 | /* /status */ |
676 | |
677 | static ssize_t |
678 | bm_status_read(struct file *file, char __user *buf, size_t nbytes, loff_t *ppos) |
679 | { |
680 | char *s = enabled ? "enabled" : "disabled"; |
681 | int len = strlen(s); |
682 | loff_t pos = *ppos; |
683 | |
684 | if (pos < 0) |
685 | return -EINVAL; |
686 | if (pos >= len) |
687 | return 0; |
688 | if (len < pos + nbytes) |
689 | nbytes = len - pos; |
690 | if (copy_to_user(buf, s + pos, nbytes)) |
691 | return -EFAULT; |
692 | *ppos = pos + nbytes; |
693 | return nbytes; |
694 | } |
695 | |
696 | static ssize_t bm_status_write(struct file * file, const char __user * buffer, |
697 | size_t count, loff_t *ppos) |
698 | { |
699 | int res = parse_command(buffer, count); |
700 | struct dentry *root; |
701 | |
702 | switch (res) { |
703 | case 1: enabled = 0; break; |
704 | case 2: enabled = 1; break; |
705 | case 3: root = dget(file->f_vfsmnt->mnt_sb->s_root); |
706 | down(&root->d_inode->i_sem); |
707 | |
708 | while (!list_empty(&entries)) |
709 | kill_node(list_entry(entries.next, Node, list)); |
710 | |
711 | up(&root->d_inode->i_sem); |
712 | dput(root); |
713 | default: return res; |
714 | } |
715 | return count; |
716 | } |
717 | |
718 | static struct file_operations bm_status_operations = { |
719 | .read = bm_status_read, |
720 | .write = bm_status_write, |
721 | }; |
722 | |
723 | /* Superblock handling */ |
724 | |
725 | static struct super_operations s_ops = { |
726 | .statfs = simple_statfs, |
727 | .clear_inode = bm_clear_inode, |
728 | }; |
729 | |
730 | static int bm_fill_super(struct super_block * sb, void * data, int silent) |
731 | { |
732 | static struct tree_descr bm_files[] = { |
733 | [1] = {"status", &bm_status_operations, S_IWUSR|S_IRUGO}, |
734 | [2] = {"register", &bm_register_operations, S_IWUSR}, |
735 | /* last one */ {""} |
736 | }; |
737 | int err = simple_fill_super(sb, 0x42494e4d, bm_files); |
738 | if (!err) |
739 | sb->s_op = &s_ops; |
740 | return err; |
741 | } |
742 | |
743 | static struct super_block *bm_get_sb(struct file_system_type *fs_type, |
744 | int flags, const char *dev_name, void *data) |
745 | { |
746 | return get_sb_single(fs_type, flags, data, bm_fill_super); |
747 | } |
748 | |
749 | static struct linux_binfmt misc_format = { |
750 | .module = THIS_MODULE, |
751 | .load_binary = load_misc_binary, |
752 | }; |
753 | |
754 | static struct file_system_type bm_fs_type = { |
755 | .owner = THIS_MODULE, |
756 | .name = "binfmt_misc", |
757 | .get_sb = bm_get_sb, |
758 | .kill_sb = kill_litter_super, |
759 | }; |
760 | |
761 | static int __init init_misc_binfmt(void) |
762 | { |
763 | int err = register_filesystem(&bm_fs_type); |
764 | if (!err) { |
765 | err = register_binfmt(&misc_format); |
766 | if (err) |
767 | unregister_filesystem(&bm_fs_type); |
768 | } |
769 | return err; |
770 | } |
771 | |
772 | static void __exit exit_misc_binfmt(void) |
773 | { |
774 | unregister_binfmt(&misc_format); |
775 | unregister_filesystem(&bm_fs_type); |
776 | } |
777 | |
778 | core_initcall(init_misc_binfmt); |
779 | module_exit(exit_misc_binfmt); |
780 | MODULE_LICENSE("GPL"); |