blob: 00687ea627385b11f0d03249b8bd038b380165ca [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
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
33enum {
34 VERBOSE_STATUS = 1 /* make it zero to save 400 bytes kernel memory */
35};
36
37static LIST_HEAD(entries);
38static int enabled = 1;
39
40enum {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
45typedef 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
57static DEFINE_RWLOCK(entries_lock);
Trond Myklebust1f5ce9e2006-06-09 09:34:16 -040058static struct file_system_type bm_fs_type;
Linus Torvalds1da177e2005-04-16 15:20:36 -070059static struct vfsmount *bm_mnt;
60static int entry_count;
61
62/*
63 * Check if we support the binfmt
64 * if we do, return the node, else NULL
65 * locking is done in load_misc_binary
66 */
67static Node *check_file(struct linux_binprm *bprm)
68{
69 char *p = strrchr(bprm->interp, '.');
70 struct list_head *l;
71
72 list_for_each(l, &entries) {
73 Node *e = list_entry(l, Node, list);
74 char *s;
75 int j;
76
77 if (!test_bit(Enabled, &e->flags))
78 continue;
79
80 if (!test_bit(Magic, &e->flags)) {
81 if (p && !strcmp(e->magic, p + 1))
82 return e;
83 continue;
84 }
85
86 s = bprm->buf + e->offset;
87 if (e->mask) {
88 for (j = 0; j < e->size; j++)
89 if ((*s++ ^ e->magic[j]) & e->mask[j])
90 break;
91 } else {
92 for (j = 0; j < e->size; j++)
93 if ((*s++ ^ e->magic[j]))
94 break;
95 }
96 if (j == e->size)
97 return e;
98 }
99 return NULL;
100}
101
102/*
103 * the loader itself
104 */
105static int load_misc_binary(struct linux_binprm *bprm, struct pt_regs *regs)
106{
107 Node *fmt;
108 struct file * interp_file = NULL;
109 char iname[BINPRM_BUF_SIZE];
110 char *iname_addr = iname;
111 int retval;
112 int fd_binary = -1;
113 struct files_struct *files = NULL;
114
115 retval = -ENOEXEC;
116 if (!enabled)
117 goto _ret;
118
119 /* to keep locking time low, we copy the interpreter string */
120 read_lock(&entries_lock);
121 fmt = check_file(bprm);
122 if (fmt)
123 strlcpy(iname, fmt->interpreter, BINPRM_BUF_SIZE);
124 read_unlock(&entries_lock);
125 if (!fmt)
126 goto _ret;
127
128 if (!(fmt->flags & MISC_FMT_PRESERVE_ARGV0)) {
129 remove_arg_zero(bprm);
130 }
131
132 if (fmt->flags & MISC_FMT_OPEN_BINARY) {
133
134 files = current->files;
135 retval = unshare_files();
136 if (retval < 0)
137 goto _ret;
138 if (files == current->files) {
139 put_files_struct(files);
140 files = NULL;
141 }
142 /* if the binary should be opened on behalf of the
143 * interpreter than keep it open and assign descriptor
144 * to it */
145 fd_binary = get_unused_fd();
146 if (fd_binary < 0) {
147 retval = fd_binary;
148 goto _unshare;
149 }
150 fd_install(fd_binary, bprm->file);
151
152 /* if the binary is not readable than enforce mm->dumpable=0
153 regardless of the interpreter's permissions */
Christoph Hellwig8c744fb2005-11-08 21:35:04 -0800154 if (file_permission(bprm->file, MAY_READ))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700155 bprm->interp_flags |= BINPRM_FLAGS_ENFORCE_NONDUMP;
156
157 allow_write_access(bprm->file);
158 bprm->file = NULL;
159
160 /* mark the bprm that fd should be passed to interp */
161 bprm->interp_flags |= BINPRM_FLAGS_EXECFD;
162 bprm->interp_data = fd_binary;
163
164 } else {
165 allow_write_access(bprm->file);
166 fput(bprm->file);
167 bprm->file = NULL;
168 }
169 /* make argv[1] be the path to the binary */
170 retval = copy_strings_kernel (1, &bprm->interp, bprm);
171 if (retval < 0)
172 goto _error;
173 bprm->argc++;
174
175 /* add the interp as argv[0] */
176 retval = copy_strings_kernel (1, &iname_addr, bprm);
177 if (retval < 0)
178 goto _error;
179 bprm->argc ++;
180
181 bprm->interp = iname; /* for binfmt_script */
182
183 interp_file = open_exec (iname);
184 retval = PTR_ERR (interp_file);
185 if (IS_ERR (interp_file))
186 goto _error;
187
188 bprm->file = interp_file;
189 if (fmt->flags & MISC_FMT_CREDENTIALS) {
190 /*
191 * No need to call prepare_binprm(), it's already been
192 * done. bprm->buf is stale, update from interp_file.
193 */
194 memset(bprm->buf, 0, BINPRM_BUF_SIZE);
195 retval = kernel_read(bprm->file, 0, bprm->buf, BINPRM_BUF_SIZE);
196 } else
197 retval = prepare_binprm (bprm);
198
199 if (retval < 0)
200 goto _error;
201
202 retval = search_binary_handler (bprm, regs);
203 if (retval < 0)
204 goto _error;
205
206 if (files) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700207 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:
Kirill Korotaev3b9b8ab2006-09-29 02:00:05 -0700218 if (files)
219 reset_files_struct(current, files);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700220 goto _ret;
221}
222
223/* Command parsers */
224
225/*
226 * parses and copies one argument enclosed in del from *sp to *dp,
227 * recognising the \x special.
228 * returns pointer to the copied argument or NULL in case of an
229 * error (and sets err) or null argument length.
230 */
231static char *scanarg(char *s, char del)
232{
233 char c;
234
235 while ((c = *s++) != del) {
236 if (c == '\\' && *s == 'x') {
237 s++;
238 if (!isxdigit(*s++))
239 return NULL;
240 if (!isxdigit(*s++))
241 return NULL;
242 }
243 }
244 return s;
245}
246
247static int unquote(char *from)
248{
249 char c = 0, *s = from, *p = from;
250
251 while ((c = *s++) != '\0') {
252 if (c == '\\' && *s == 'x') {
253 s++;
254 c = toupper(*s++);
255 *p = (c - (isdigit(c) ? '0' : 'A' - 10)) << 4;
256 c = toupper(*s++);
257 *p++ |= c - (isdigit(c) ? '0' : 'A' - 10);
258 continue;
259 }
260 *p++ = c;
261 }
262 return p - from;
263}
264
Arjan van de Ven858119e2006-01-14 13:20:43 -0800265static char * check_special_flags (char * sfs, Node * e)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700266{
267 char * p = sfs;
268 int cont = 1;
269
270 /* special flags */
271 while (cont) {
272 switch (*p) {
273 case 'P':
274 p++;
275 e->flags |= MISC_FMT_PRESERVE_ARGV0;
276 break;
277 case 'O':
278 p++;
279 e->flags |= MISC_FMT_OPEN_BINARY;
280 break;
281 case 'C':
282 p++;
283 /* this flags also implies the
284 open-binary flag */
285 e->flags |= (MISC_FMT_CREDENTIALS |
286 MISC_FMT_OPEN_BINARY);
287 break;
288 default:
289 cont = 0;
290 }
291 }
292
293 return p;
294}
295/*
296 * This registers a new binary format, it recognises the syntax
297 * ':name:type:offset:magic:mask:interpreter:flags'
298 * where the ':' is the IFS, that can be chosen with the first char
299 */
300static Node *create_entry(const char __user *buffer, size_t count)
301{
302 Node *e;
303 int memsize, err;
304 char *buf, *p;
305 char del;
306
307 /* some sanity checks */
308 err = -EINVAL;
309 if ((count < 11) || (count > 256))
310 goto out;
311
312 err = -ENOMEM;
313 memsize = sizeof(Node) + count + 8;
314 e = (Node *) kmalloc(memsize, GFP_USER);
315 if (!e)
316 goto out;
317
318 p = buf = (char *)e + sizeof(Node);
319
320 memset(e, 0, sizeof(Node));
321 if (copy_from_user(buf, buffer, count))
322 goto Efault;
323
324 del = *p++; /* delimeter */
325
326 memset(buf+count, del, 8);
327
328 e->name = p;
329 p = strchr(p, del);
330 if (!p)
331 goto Einval;
332 *p++ = '\0';
333 if (!e->name[0] ||
334 !strcmp(e->name, ".") ||
335 !strcmp(e->name, "..") ||
336 strchr(e->name, '/'))
337 goto Einval;
338 switch (*p++) {
339 case 'E': e->flags = 1<<Enabled; break;
340 case 'M': e->flags = (1<<Enabled) | (1<<Magic); break;
341 default: goto Einval;
342 }
343 if (*p++ != del)
344 goto Einval;
345 if (test_bit(Magic, &e->flags)) {
346 char *s = strchr(p, del);
347 if (!s)
348 goto Einval;
349 *s++ = '\0';
350 e->offset = simple_strtoul(p, &p, 10);
351 if (*p++)
352 goto Einval;
353 e->magic = p;
354 p = scanarg(p, del);
355 if (!p)
356 goto Einval;
357 p[-1] = '\0';
358 if (!e->magic[0])
359 goto Einval;
360 e->mask = p;
361 p = scanarg(p, del);
362 if (!p)
363 goto Einval;
364 p[-1] = '\0';
365 if (!e->mask[0])
366 e->mask = NULL;
367 e->size = unquote(e->magic);
368 if (e->mask && unquote(e->mask) != e->size)
369 goto Einval;
370 if (e->size + e->offset > BINPRM_BUF_SIZE)
371 goto Einval;
372 } else {
373 p = strchr(p, del);
374 if (!p)
375 goto Einval;
376 *p++ = '\0';
377 e->magic = p;
378 p = strchr(p, del);
379 if (!p)
380 goto Einval;
381 *p++ = '\0';
382 if (!e->magic[0] || strchr(e->magic, '/'))
383 goto Einval;
384 p = strchr(p, del);
385 if (!p)
386 goto Einval;
387 *p++ = '\0';
388 }
389 e->interpreter = p;
390 p = strchr(p, del);
391 if (!p)
392 goto Einval;
393 *p++ = '\0';
394 if (!e->interpreter[0])
395 goto Einval;
396
397
398 p = check_special_flags (p, e);
399
400 if (*p == '\n')
401 p++;
402 if (p != buf + count)
403 goto Einval;
404 return e;
405
406out:
407 return ERR_PTR(err);
408
409Efault:
410 kfree(e);
411 return ERR_PTR(-EFAULT);
412Einval:
413 kfree(e);
414 return ERR_PTR(-EINVAL);
415}
416
417/*
418 * Set status of entry/binfmt_misc:
419 * '1' enables, '0' disables and '-1' clears entry/binfmt_misc
420 */
421static int parse_command(const char __user *buffer, size_t count)
422{
423 char s[4];
424
425 if (!count)
426 return 0;
427 if (count > 3)
428 return -EINVAL;
429 if (copy_from_user(s, buffer, count))
430 return -EFAULT;
431 if (s[count-1] == '\n')
432 count--;
433 if (count == 1 && s[0] == '0')
434 return 1;
435 if (count == 1 && s[0] == '1')
436 return 2;
437 if (count == 2 && s[0] == '-' && s[1] == '1')
438 return 3;
439 return -EINVAL;
440}
441
442/* generic stuff */
443
444static void entry_status(Node *e, char *page)
445{
446 char *dp;
447 char *status = "disabled";
448 const char * flags = "flags: ";
449
450 if (test_bit(Enabled, &e->flags))
451 status = "enabled";
452
453 if (!VERBOSE_STATUS) {
454 sprintf(page, "%s\n", status);
455 return;
456 }
457
458 sprintf(page, "%s\ninterpreter %s\n", status, e->interpreter);
459 dp = page + strlen(page);
460
461 /* print the special flags */
462 sprintf (dp, "%s", flags);
463 dp += strlen (flags);
464 if (e->flags & MISC_FMT_PRESERVE_ARGV0) {
465 *dp ++ = 'P';
466 }
467 if (e->flags & MISC_FMT_OPEN_BINARY) {
468 *dp ++ = 'O';
469 }
470 if (e->flags & MISC_FMT_CREDENTIALS) {
471 *dp ++ = 'C';
472 }
473 *dp ++ = '\n';
474
475
476 if (!test_bit(Magic, &e->flags)) {
477 sprintf(dp, "extension .%s\n", e->magic);
478 } else {
479 int i;
480
481 sprintf(dp, "offset %i\nmagic ", e->offset);
482 dp = page + strlen(page);
483 for (i = 0; i < e->size; i++) {
484 sprintf(dp, "%02x", 0xff & (int) (e->magic[i]));
485 dp += 2;
486 }
487 if (e->mask) {
488 sprintf(dp, "\nmask ");
489 dp += 6;
490 for (i = 0; i < e->size; i++) {
491 sprintf(dp, "%02x", 0xff & (int) (e->mask[i]));
492 dp += 2;
493 }
494 }
495 *dp++ = '\n';
496 *dp = '\0';
497 }
498}
499
500static struct inode *bm_get_inode(struct super_block *sb, int mode)
501{
502 struct inode * inode = new_inode(sb);
503
504 if (inode) {
505 inode->i_mode = mode;
506 inode->i_uid = 0;
507 inode->i_gid = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700508 inode->i_blocks = 0;
509 inode->i_atime = inode->i_mtime = inode->i_ctime =
510 current_fs_time(inode->i_sb);
511 }
512 return inode;
513}
514
515static void bm_clear_inode(struct inode *inode)
516{
Theodore Ts'o8e18e292006-09-27 01:50:46 -0700517 kfree(inode->i_private);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700518}
519
520static void kill_node(Node *e)
521{
522 struct dentry *dentry;
523
524 write_lock(&entries_lock);
525 dentry = e->dentry;
526 if (dentry) {
527 list_del_init(&e->list);
528 e->dentry = NULL;
529 }
530 write_unlock(&entries_lock);
531
532 if (dentry) {
533 dentry->d_inode->i_nlink--;
534 d_drop(dentry);
535 dput(dentry);
536 simple_release_fs(&bm_mnt, &entry_count);
537 }
538}
539
540/* /<entry> */
541
542static ssize_t
543bm_entry_read(struct file * file, char __user * buf, size_t nbytes, loff_t *ppos)
544{
Josef "Jeff" Sipek0f7fc9e2006-12-08 02:36:35 -0800545 Node *e = file->f_path.dentry->d_inode->i_private;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700546 loff_t pos = *ppos;
547 ssize_t res;
548 char *page;
549 int len;
550
551 if (!(page = (char*) __get_free_page(GFP_KERNEL)))
552 return -ENOMEM;
553
554 entry_status(e, page);
555 len = strlen(page);
556
557 res = -EINVAL;
558 if (pos < 0)
559 goto out;
560 res = 0;
561 if (pos >= len)
562 goto out;
563 if (len < pos + nbytes)
564 nbytes = len - pos;
565 res = -EFAULT;
566 if (copy_to_user(buf, page + pos, nbytes))
567 goto out;
568 *ppos = pos + nbytes;
569 res = nbytes;
570out:
571 free_page((unsigned long) page);
572 return res;
573}
574
575static ssize_t bm_entry_write(struct file *file, const char __user *buffer,
576 size_t count, loff_t *ppos)
577{
578 struct dentry *root;
Josef "Jeff" Sipek0f7fc9e2006-12-08 02:36:35 -0800579 Node *e = file->f_path.dentry->d_inode->i_private;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700580 int res = parse_command(buffer, count);
581
582 switch (res) {
583 case 1: clear_bit(Enabled, &e->flags);
584 break;
585 case 2: set_bit(Enabled, &e->flags);
586 break;
Josef "Jeff" Sipek0f7fc9e2006-12-08 02:36:35 -0800587 case 3: root = dget(file->f_path.mnt->mnt_sb->s_root);
Jes Sorensen1b1dcc12006-01-09 15:59:24 -0800588 mutex_lock(&root->d_inode->i_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700589
590 kill_node(e);
591
Jes Sorensen1b1dcc12006-01-09 15:59:24 -0800592 mutex_unlock(&root->d_inode->i_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700593 dput(root);
594 break;
595 default: return res;
596 }
597 return count;
598}
599
Arjan van de Ven4b6f5d22006-03-28 01:56:42 -0800600static const struct file_operations bm_entry_operations = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700601 .read = bm_entry_read,
602 .write = bm_entry_write,
603};
604
605/* /register */
606
607static ssize_t bm_register_write(struct file *file, const char __user *buffer,
608 size_t count, loff_t *ppos)
609{
610 Node *e;
611 struct inode *inode;
612 struct dentry *root, *dentry;
Josef "Jeff" Sipek0f7fc9e2006-12-08 02:36:35 -0800613 struct super_block *sb = file->f_path.mnt->mnt_sb;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700614 int err = 0;
615
616 e = create_entry(buffer, count);
617
618 if (IS_ERR(e))
619 return PTR_ERR(e);
620
621 root = dget(sb->s_root);
Jes Sorensen1b1dcc12006-01-09 15:59:24 -0800622 mutex_lock(&root->d_inode->i_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700623 dentry = lookup_one_len(e->name, root, strlen(e->name));
624 err = PTR_ERR(dentry);
625 if (IS_ERR(dentry))
626 goto out;
627
628 err = -EEXIST;
629 if (dentry->d_inode)
630 goto out2;
631
632 inode = bm_get_inode(sb, S_IFREG | 0644);
633
634 err = -ENOMEM;
635 if (!inode)
636 goto out2;
637
Trond Myklebust1f5ce9e2006-06-09 09:34:16 -0400638 err = simple_pin_fs(&bm_fs_type, &bm_mnt, &entry_count);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700639 if (err) {
640 iput(inode);
641 inode = NULL;
642 goto out2;
643 }
644
645 e->dentry = dget(dentry);
Theodore Ts'o8e18e292006-09-27 01:50:46 -0700646 inode->i_private = e;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700647 inode->i_fop = &bm_entry_operations;
648
649 d_instantiate(dentry, inode);
650 write_lock(&entries_lock);
651 list_add(&e->list, &entries);
652 write_unlock(&entries_lock);
653
654 err = 0;
655out2:
656 dput(dentry);
657out:
Jes Sorensen1b1dcc12006-01-09 15:59:24 -0800658 mutex_unlock(&root->d_inode->i_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700659 dput(root);
660
661 if (err) {
662 kfree(e);
663 return -EINVAL;
664 }
665 return count;
666}
667
Arjan van de Ven4b6f5d22006-03-28 01:56:42 -0800668static const struct file_operations bm_register_operations = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700669 .write = bm_register_write,
670};
671
672/* /status */
673
674static ssize_t
675bm_status_read(struct file *file, char __user *buf, size_t nbytes, loff_t *ppos)
676{
677 char *s = enabled ? "enabled" : "disabled";
678 int len = strlen(s);
679 loff_t pos = *ppos;
680
681 if (pos < 0)
682 return -EINVAL;
683 if (pos >= len)
684 return 0;
685 if (len < pos + nbytes)
686 nbytes = len - pos;
687 if (copy_to_user(buf, s + pos, nbytes))
688 return -EFAULT;
689 *ppos = pos + nbytes;
690 return nbytes;
691}
692
693static ssize_t bm_status_write(struct file * file, const char __user * buffer,
694 size_t count, loff_t *ppos)
695{
696 int res = parse_command(buffer, count);
697 struct dentry *root;
698
699 switch (res) {
700 case 1: enabled = 0; break;
701 case 2: enabled = 1; break;
Josef "Jeff" Sipek0f7fc9e2006-12-08 02:36:35 -0800702 case 3: root = dget(file->f_path.mnt->mnt_sb->s_root);
Jes Sorensen1b1dcc12006-01-09 15:59:24 -0800703 mutex_lock(&root->d_inode->i_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700704
705 while (!list_empty(&entries))
706 kill_node(list_entry(entries.next, Node, list));
707
Jes Sorensen1b1dcc12006-01-09 15:59:24 -0800708 mutex_unlock(&root->d_inode->i_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700709 dput(root);
710 default: return res;
711 }
712 return count;
713}
714
Arjan van de Ven4b6f5d22006-03-28 01:56:42 -0800715static const struct file_operations bm_status_operations = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700716 .read = bm_status_read,
717 .write = bm_status_write,
718};
719
720/* Superblock handling */
721
722static struct super_operations s_ops = {
723 .statfs = simple_statfs,
724 .clear_inode = bm_clear_inode,
725};
726
727static int bm_fill_super(struct super_block * sb, void * data, int silent)
728{
729 static struct tree_descr bm_files[] = {
730 [1] = {"status", &bm_status_operations, S_IWUSR|S_IRUGO},
731 [2] = {"register", &bm_register_operations, S_IWUSR},
732 /* last one */ {""}
733 };
734 int err = simple_fill_super(sb, 0x42494e4d, bm_files);
735 if (!err)
736 sb->s_op = &s_ops;
737 return err;
738}
739
David Howells454e2392006-06-23 02:02:57 -0700740static int bm_get_sb(struct file_system_type *fs_type,
741 int flags, const char *dev_name, void *data, struct vfsmount *mnt)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700742{
David Howells454e2392006-06-23 02:02:57 -0700743 return get_sb_single(fs_type, flags, data, bm_fill_super, mnt);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700744}
745
746static struct linux_binfmt misc_format = {
747 .module = THIS_MODULE,
748 .load_binary = load_misc_binary,
749};
750
751static struct file_system_type bm_fs_type = {
752 .owner = THIS_MODULE,
753 .name = "binfmt_misc",
754 .get_sb = bm_get_sb,
755 .kill_sb = kill_litter_super,
756};
757
758static int __init init_misc_binfmt(void)
759{
760 int err = register_filesystem(&bm_fs_type);
761 if (!err) {
762 err = register_binfmt(&misc_format);
763 if (err)
764 unregister_filesystem(&bm_fs_type);
765 }
766 return err;
767}
768
769static void __exit exit_misc_binfmt(void)
770{
771 unregister_binfmt(&misc_format);
772 unregister_filesystem(&bm_fs_type);
773}
774
775core_initcall(init_misc_binfmt);
776module_exit(exit_misc_binfmt);
777MODULE_LICENSE("GPL");