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Linux/fs/nfs/idmap.c

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  1 /*
  2  * fs/nfs/idmap.c
  3  *
  4  *  UID and GID to name mapping for clients.
  5  *
  6  *  Copyright (c) 2002 The Regents of the University of Michigan.
  7  *  All rights reserved.
  8  *
  9  *  Marius Aamodt Eriksen <marius@umich.edu>
 10  *
 11  *  Redistribution and use in source and binary forms, with or without
 12  *  modification, are permitted provided that the following conditions
 13  *  are met:
 14  *
 15  *  1. Redistributions of source code must retain the above copyright
 16  *     notice, this list of conditions and the following disclaimer.
 17  *  2. Redistributions in binary form must reproduce the above copyright
 18  *     notice, this list of conditions and the following disclaimer in the
 19  *     documentation and/or other materials provided with the distribution.
 20  *  3. Neither the name of the University nor the names of its
 21  *     contributors may be used to endorse or promote products derived
 22  *     from this software without specific prior written permission.
 23  *
 24  *  THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
 25  *  WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
 26  *  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 27  *  DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 28  *  FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 29  *  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 30  *  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
 31  *  BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 32  *  LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 33  *  NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 34  *  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 35  */
 36 #include <linux/types.h>
 37 #include <linux/parser.h>
 38 #include <linux/fs.h>
 39 #include <linux/nfs_idmap.h>
 40 #include <net/net_namespace.h>
 41 #include <linux/sunrpc/rpc_pipe_fs.h>
 42 #include <linux/nfs_fs.h>
 43 #include <linux/nfs_fs_sb.h>
 44 #include <linux/key.h>
 45 #include <linux/keyctl.h>
 46 #include <linux/key-type.h>
 47 #include <keys/user-type.h>
 48 #include <linux/module.h>
 49 
 50 #include "internal.h"
 51 #include "netns.h"
 52 #include "nfs4trace.h"
 53 
 54 #define NFS_UINT_MAXLEN 11
 55 
 56 static const struct cred *id_resolver_cache;
 57 static struct key_type key_type_id_resolver_legacy;
 58 
 59 struct idmap_legacy_upcalldata {
 60         struct rpc_pipe_msg pipe_msg;
 61         struct idmap_msg idmap_msg;
 62         struct key_construction *key_cons;
 63         struct idmap *idmap;
 64 };
 65 
 66 struct idmap {
 67         struct rpc_pipe_dir_object idmap_pdo;
 68         struct rpc_pipe         *idmap_pipe;
 69         struct idmap_legacy_upcalldata *idmap_upcall_data;
 70         struct mutex            idmap_mutex;
 71 };
 72 
 73 /**
 74  * nfs_fattr_init_names - initialise the nfs_fattr owner_name/group_name fields
 75  * @fattr: fully initialised struct nfs_fattr
 76  * @owner_name: owner name string cache
 77  * @group_name: group name string cache
 78  */
 79 void nfs_fattr_init_names(struct nfs_fattr *fattr,
 80                 struct nfs4_string *owner_name,
 81                 struct nfs4_string *group_name)
 82 {
 83         fattr->owner_name = owner_name;
 84         fattr->group_name = group_name;
 85 }
 86 
 87 static void nfs_fattr_free_owner_name(struct nfs_fattr *fattr)
 88 {
 89         fattr->valid &= ~NFS_ATTR_FATTR_OWNER_NAME;
 90         kfree(fattr->owner_name->data);
 91 }
 92 
 93 static void nfs_fattr_free_group_name(struct nfs_fattr *fattr)
 94 {
 95         fattr->valid &= ~NFS_ATTR_FATTR_GROUP_NAME;
 96         kfree(fattr->group_name->data);
 97 }
 98 
 99 static bool nfs_fattr_map_owner_name(struct nfs_server *server, struct nfs_fattr *fattr)
100 {
101         struct nfs4_string *owner = fattr->owner_name;
102         kuid_t uid;
103 
104         if (!(fattr->valid & NFS_ATTR_FATTR_OWNER_NAME))
105                 return false;
106         if (nfs_map_name_to_uid(server, owner->data, owner->len, &uid) == 0) {
107                 fattr->uid = uid;
108                 fattr->valid |= NFS_ATTR_FATTR_OWNER;
109         }
110         return true;
111 }
112 
113 static bool nfs_fattr_map_group_name(struct nfs_server *server, struct nfs_fattr *fattr)
114 {
115         struct nfs4_string *group = fattr->group_name;
116         kgid_t gid;
117 
118         if (!(fattr->valid & NFS_ATTR_FATTR_GROUP_NAME))
119                 return false;
120         if (nfs_map_group_to_gid(server, group->data, group->len, &gid) == 0) {
121                 fattr->gid = gid;
122                 fattr->valid |= NFS_ATTR_FATTR_GROUP;
123         }
124         return true;
125 }
126 
127 /**
128  * nfs_fattr_free_names - free up the NFSv4 owner and group strings
129  * @fattr: a fully initialised nfs_fattr structure
130  */
131 void nfs_fattr_free_names(struct nfs_fattr *fattr)
132 {
133         if (fattr->valid & NFS_ATTR_FATTR_OWNER_NAME)
134                 nfs_fattr_free_owner_name(fattr);
135         if (fattr->valid & NFS_ATTR_FATTR_GROUP_NAME)
136                 nfs_fattr_free_group_name(fattr);
137 }
138 
139 /**
140  * nfs_fattr_map_and_free_names - map owner/group strings into uid/gid and free
141  * @server: pointer to the filesystem nfs_server structure
142  * @fattr: a fully initialised nfs_fattr structure
143  *
144  * This helper maps the cached NFSv4 owner/group strings in fattr into
145  * their numeric uid/gid equivalents, and then frees the cached strings.
146  */
147 void nfs_fattr_map_and_free_names(struct nfs_server *server, struct nfs_fattr *fattr)
148 {
149         if (nfs_fattr_map_owner_name(server, fattr))
150                 nfs_fattr_free_owner_name(fattr);
151         if (nfs_fattr_map_group_name(server, fattr))
152                 nfs_fattr_free_group_name(fattr);
153 }
154 
155 static int nfs_map_string_to_numeric(const char *name, size_t namelen, __u32 *res)
156 {
157         unsigned long val;
158         char buf[16];
159 
160         if (memchr(name, '@', namelen) != NULL || namelen >= sizeof(buf))
161                 return 0;
162         memcpy(buf, name, namelen);
163         buf[namelen] = '\0';
164         if (kstrtoul(buf, 0, &val) != 0)
165                 return 0;
166         *res = val;
167         return 1;
168 }
169 
170 static int nfs_map_numeric_to_string(__u32 id, char *buf, size_t buflen)
171 {
172         return snprintf(buf, buflen, "%u", id);
173 }
174 
175 static struct key_type key_type_id_resolver = {
176         .name           = "id_resolver",
177         .instantiate    = user_instantiate,
178         .match          = user_match,
179         .revoke         = user_revoke,
180         .destroy        = user_destroy,
181         .describe       = user_describe,
182         .read           = user_read,
183 };
184 
185 static int nfs_idmap_init_keyring(void)
186 {
187         struct cred *cred;
188         struct key *keyring;
189         int ret = 0;
190 
191         printk(KERN_NOTICE "NFS: Registering the %s key type\n",
192                 key_type_id_resolver.name);
193 
194         cred = prepare_kernel_cred(NULL);
195         if (!cred)
196                 return -ENOMEM;
197 
198         keyring = keyring_alloc(".id_resolver",
199                                 GLOBAL_ROOT_UID, GLOBAL_ROOT_GID, cred,
200                                 (KEY_POS_ALL & ~KEY_POS_SETATTR) |
201                                 KEY_USR_VIEW | KEY_USR_READ,
202                                 KEY_ALLOC_NOT_IN_QUOTA, NULL);
203         if (IS_ERR(keyring)) {
204                 ret = PTR_ERR(keyring);
205                 goto failed_put_cred;
206         }
207 
208         ret = register_key_type(&key_type_id_resolver);
209         if (ret < 0)
210                 goto failed_put_key;
211 
212         ret = register_key_type(&key_type_id_resolver_legacy);
213         if (ret < 0)
214                 goto failed_reg_legacy;
215 
216         set_bit(KEY_FLAG_ROOT_CAN_CLEAR, &keyring->flags);
217         cred->thread_keyring = keyring;
218         cred->jit_keyring = KEY_REQKEY_DEFL_THREAD_KEYRING;
219         id_resolver_cache = cred;
220         return 0;
221 
222 failed_reg_legacy:
223         unregister_key_type(&key_type_id_resolver);
224 failed_put_key:
225         key_put(keyring);
226 failed_put_cred:
227         put_cred(cred);
228         return ret;
229 }
230 
231 static void nfs_idmap_quit_keyring(void)
232 {
233         key_revoke(id_resolver_cache->thread_keyring);
234         unregister_key_type(&key_type_id_resolver);
235         unregister_key_type(&key_type_id_resolver_legacy);
236         put_cred(id_resolver_cache);
237 }
238 
239 /*
240  * Assemble the description to pass to request_key()
241  * This function will allocate a new string and update dest to point
242  * at it.  The caller is responsible for freeing dest.
243  *
244  * On error 0 is returned.  Otherwise, the length of dest is returned.
245  */
246 static ssize_t nfs_idmap_get_desc(const char *name, size_t namelen,
247                                 const char *type, size_t typelen, char **desc)
248 {
249         char *cp;
250         size_t desclen = typelen + namelen + 2;
251 
252         *desc = kmalloc(desclen, GFP_KERNEL);
253         if (!*desc)
254                 return -ENOMEM;
255 
256         cp = *desc;
257         memcpy(cp, type, typelen);
258         cp += typelen;
259         *cp++ = ':';
260 
261         memcpy(cp, name, namelen);
262         cp += namelen;
263         *cp = '\0';
264         return desclen;
265 }
266 
267 static struct key *nfs_idmap_request_key(const char *name, size_t namelen,
268                                          const char *type, struct idmap *idmap)
269 {
270         char *desc;
271         struct key *rkey;
272         ssize_t ret;
273 
274         ret = nfs_idmap_get_desc(name, namelen, type, strlen(type), &desc);
275         if (ret <= 0)
276                 return ERR_PTR(ret);
277 
278         rkey = request_key(&key_type_id_resolver, desc, "");
279         if (IS_ERR(rkey)) {
280                 mutex_lock(&idmap->idmap_mutex);
281                 rkey = request_key_with_auxdata(&key_type_id_resolver_legacy,
282                                                 desc, "", 0, idmap);
283                 mutex_unlock(&idmap->idmap_mutex);
284         }
285 
286         kfree(desc);
287         return rkey;
288 }
289 
290 static ssize_t nfs_idmap_get_key(const char *name, size_t namelen,
291                                  const char *type, void *data,
292                                  size_t data_size, struct idmap *idmap)
293 {
294         const struct cred *saved_cred;
295         struct key *rkey;
296         struct user_key_payload *payload;
297         ssize_t ret;
298 
299         saved_cred = override_creds(id_resolver_cache);
300         rkey = nfs_idmap_request_key(name, namelen, type, idmap);
301         revert_creds(saved_cred);
302 
303         if (IS_ERR(rkey)) {
304                 ret = PTR_ERR(rkey);
305                 goto out;
306         }
307 
308         rcu_read_lock();
309         rkey->perm |= KEY_USR_VIEW;
310 
311         ret = key_validate(rkey);
312         if (ret < 0)
313                 goto out_up;
314 
315         payload = rcu_dereference(rkey->payload.rcudata);
316         if (IS_ERR_OR_NULL(payload)) {
317                 ret = PTR_ERR(payload);
318                 goto out_up;
319         }
320 
321         ret = payload->datalen;
322         if (ret > 0 && ret <= data_size)
323                 memcpy(data, payload->data, ret);
324         else
325                 ret = -EINVAL;
326 
327 out_up:
328         rcu_read_unlock();
329         key_put(rkey);
330 out:
331         return ret;
332 }
333 
334 /* ID -> Name */
335 static ssize_t nfs_idmap_lookup_name(__u32 id, const char *type, char *buf,
336                                      size_t buflen, struct idmap *idmap)
337 {
338         char id_str[NFS_UINT_MAXLEN];
339         int id_len;
340         ssize_t ret;
341 
342         id_len = snprintf(id_str, sizeof(id_str), "%u", id);
343         ret = nfs_idmap_get_key(id_str, id_len, type, buf, buflen, idmap);
344         if (ret < 0)
345                 return -EINVAL;
346         return ret;
347 }
348 
349 /* Name -> ID */
350 static int nfs_idmap_lookup_id(const char *name, size_t namelen, const char *type,
351                                __u32 *id, struct idmap *idmap)
352 {
353         char id_str[NFS_UINT_MAXLEN];
354         long id_long;
355         ssize_t data_size;
356         int ret = 0;
357 
358         data_size = nfs_idmap_get_key(name, namelen, type, id_str, NFS_UINT_MAXLEN, idmap);
359         if (data_size <= 0) {
360                 ret = -EINVAL;
361         } else {
362                 ret = kstrtol(id_str, 10, &id_long);
363                 *id = (__u32)id_long;
364         }
365         return ret;
366 }
367 
368 /* idmap classic begins here */
369 
370 enum {
371         Opt_find_uid, Opt_find_gid, Opt_find_user, Opt_find_group, Opt_find_err
372 };
373 
374 static const match_table_t nfs_idmap_tokens = {
375         { Opt_find_uid, "uid:%s" },
376         { Opt_find_gid, "gid:%s" },
377         { Opt_find_user, "user:%s" },
378         { Opt_find_group, "group:%s" },
379         { Opt_find_err, NULL }
380 };
381 
382 static int nfs_idmap_legacy_upcall(struct key_construction *, const char *, void *);
383 static ssize_t idmap_pipe_downcall(struct file *, const char __user *,
384                                    size_t);
385 static void idmap_release_pipe(struct inode *);
386 static void idmap_pipe_destroy_msg(struct rpc_pipe_msg *);
387 
388 static const struct rpc_pipe_ops idmap_upcall_ops = {
389         .upcall         = rpc_pipe_generic_upcall,
390         .downcall       = idmap_pipe_downcall,
391         .release_pipe   = idmap_release_pipe,
392         .destroy_msg    = idmap_pipe_destroy_msg,
393 };
394 
395 static struct key_type key_type_id_resolver_legacy = {
396         .name           = "id_legacy",
397         .instantiate    = user_instantiate,
398         .match          = user_match,
399         .revoke         = user_revoke,
400         .destroy        = user_destroy,
401         .describe       = user_describe,
402         .read           = user_read,
403         .request_key    = nfs_idmap_legacy_upcall,
404 };
405 
406 static void nfs_idmap_pipe_destroy(struct dentry *dir,
407                 struct rpc_pipe_dir_object *pdo)
408 {
409         struct idmap *idmap = pdo->pdo_data;
410         struct rpc_pipe *pipe = idmap->idmap_pipe;
411 
412         if (pipe->dentry) {
413                 rpc_unlink(pipe->dentry);
414                 pipe->dentry = NULL;
415         }
416 }
417 
418 static int nfs_idmap_pipe_create(struct dentry *dir,
419                 struct rpc_pipe_dir_object *pdo)
420 {
421         struct idmap *idmap = pdo->pdo_data;
422         struct rpc_pipe *pipe = idmap->idmap_pipe;
423         struct dentry *dentry;
424 
425         dentry = rpc_mkpipe_dentry(dir, "idmap", idmap, pipe);
426         if (IS_ERR(dentry))
427                 return PTR_ERR(dentry);
428         pipe->dentry = dentry;
429         return 0;
430 }
431 
432 static const struct rpc_pipe_dir_object_ops nfs_idmap_pipe_dir_object_ops = {
433         .create = nfs_idmap_pipe_create,
434         .destroy = nfs_idmap_pipe_destroy,
435 };
436 
437 int
438 nfs_idmap_new(struct nfs_client *clp)
439 {
440         struct idmap *idmap;
441         struct rpc_pipe *pipe;
442         int error;
443 
444         idmap = kzalloc(sizeof(*idmap), GFP_KERNEL);
445         if (idmap == NULL)
446                 return -ENOMEM;
447 
448         rpc_init_pipe_dir_object(&idmap->idmap_pdo,
449                         &nfs_idmap_pipe_dir_object_ops,
450                         idmap);
451 
452         pipe = rpc_mkpipe_data(&idmap_upcall_ops, 0);
453         if (IS_ERR(pipe)) {
454                 error = PTR_ERR(pipe);
455                 goto err;
456         }
457         idmap->idmap_pipe = pipe;
458         mutex_init(&idmap->idmap_mutex);
459 
460         error = rpc_add_pipe_dir_object(clp->cl_net,
461                         &clp->cl_rpcclient->cl_pipedir_objects,
462                         &idmap->idmap_pdo);
463         if (error)
464                 goto err_destroy_pipe;
465 
466         clp->cl_idmap = idmap;
467         return 0;
468 err_destroy_pipe:
469         rpc_destroy_pipe_data(idmap->idmap_pipe);
470 err:
471         kfree(idmap);
472         return error;
473 }
474 
475 void
476 nfs_idmap_delete(struct nfs_client *clp)
477 {
478         struct idmap *idmap = clp->cl_idmap;
479 
480         if (!idmap)
481                 return;
482         clp->cl_idmap = NULL;
483         rpc_remove_pipe_dir_object(clp->cl_net,
484                         &clp->cl_rpcclient->cl_pipedir_objects,
485                         &idmap->idmap_pdo);
486         rpc_destroy_pipe_data(idmap->idmap_pipe);
487         kfree(idmap);
488 }
489 
490 int nfs_idmap_init(void)
491 {
492         int ret;
493         ret = nfs_idmap_init_keyring();
494         if (ret != 0)
495                 goto out;
496 out:
497         return ret;
498 }
499 
500 void nfs_idmap_quit(void)
501 {
502         nfs_idmap_quit_keyring();
503 }
504 
505 static int nfs_idmap_prepare_message(char *desc, struct idmap *idmap,
506                                      struct idmap_msg *im,
507                                      struct rpc_pipe_msg *msg)
508 {
509         substring_t substr;
510         int token, ret;
511 
512         im->im_type = IDMAP_TYPE_GROUP;
513         token = match_token(desc, nfs_idmap_tokens, &substr);
514 
515         switch (token) {
516         case Opt_find_uid:
517                 im->im_type = IDMAP_TYPE_USER;
518         case Opt_find_gid:
519                 im->im_conv = IDMAP_CONV_NAMETOID;
520                 ret = match_strlcpy(im->im_name, &substr, IDMAP_NAMESZ);
521                 break;
522 
523         case Opt_find_user:
524                 im->im_type = IDMAP_TYPE_USER;
525         case Opt_find_group:
526                 im->im_conv = IDMAP_CONV_IDTONAME;
527                 ret = match_int(&substr, &im->im_id);
528                 break;
529 
530         default:
531                 ret = -EINVAL;
532                 goto out;
533         }
534 
535         msg->data = im;
536         msg->len  = sizeof(struct idmap_msg);
537 
538 out:
539         return ret;
540 }
541 
542 static bool
543 nfs_idmap_prepare_pipe_upcall(struct idmap *idmap,
544                 struct idmap_legacy_upcalldata *data)
545 {
546         if (idmap->idmap_upcall_data != NULL) {
547                 WARN_ON_ONCE(1);
548                 return false;
549         }
550         idmap->idmap_upcall_data = data;
551         return true;
552 }
553 
554 static void
555 nfs_idmap_complete_pipe_upcall_locked(struct idmap *idmap, int ret)
556 {
557         struct key_construction *cons = idmap->idmap_upcall_data->key_cons;
558 
559         kfree(idmap->idmap_upcall_data);
560         idmap->idmap_upcall_data = NULL;
561         complete_request_key(cons, ret);
562 }
563 
564 static void
565 nfs_idmap_abort_pipe_upcall(struct idmap *idmap, int ret)
566 {
567         if (idmap->idmap_upcall_data != NULL)
568                 nfs_idmap_complete_pipe_upcall_locked(idmap, ret);
569 }
570 
571 static int nfs_idmap_legacy_upcall(struct key_construction *cons,
572                                    const char *op,
573                                    void *aux)
574 {
575         struct idmap_legacy_upcalldata *data;
576         struct rpc_pipe_msg *msg;
577         struct idmap_msg *im;
578         struct idmap *idmap = (struct idmap *)aux;
579         struct key *key = cons->key;
580         int ret = -ENOMEM;
581 
582         /* msg and im are freed in idmap_pipe_destroy_msg */
583         data = kzalloc(sizeof(*data), GFP_KERNEL);
584         if (!data)
585                 goto out1;
586 
587         msg = &data->pipe_msg;
588         im = &data->idmap_msg;
589         data->idmap = idmap;
590         data->key_cons = cons;
591 
592         ret = nfs_idmap_prepare_message(key->description, idmap, im, msg);
593         if (ret < 0)
594                 goto out2;
595 
596         ret = -EAGAIN;
597         if (!nfs_idmap_prepare_pipe_upcall(idmap, data))
598                 goto out2;
599 
600         ret = rpc_queue_upcall(idmap->idmap_pipe, msg);
601         if (ret < 0)
602                 nfs_idmap_abort_pipe_upcall(idmap, ret);
603 
604         return ret;
605 out2:
606         kfree(data);
607 out1:
608         complete_request_key(cons, ret);
609         return ret;
610 }
611 
612 static int nfs_idmap_instantiate(struct key *key, struct key *authkey, char *data, size_t datalen)
613 {
614         return key_instantiate_and_link(key, data, datalen,
615                                         id_resolver_cache->thread_keyring,
616                                         authkey);
617 }
618 
619 static int nfs_idmap_read_and_verify_message(struct idmap_msg *im,
620                 struct idmap_msg *upcall,
621                 struct key *key, struct key *authkey)
622 {
623         char id_str[NFS_UINT_MAXLEN];
624         size_t len;
625         int ret = -ENOKEY;
626 
627         /* ret = -ENOKEY */
628         if (upcall->im_type != im->im_type || upcall->im_conv != im->im_conv)
629                 goto out;
630         switch (im->im_conv) {
631         case IDMAP_CONV_NAMETOID:
632                 if (strcmp(upcall->im_name, im->im_name) != 0)
633                         break;
634                 /* Note: here we store the NUL terminator too */
635                 len = sprintf(id_str, "%d", im->im_id) + 1;
636                 ret = nfs_idmap_instantiate(key, authkey, id_str, len);
637                 break;
638         case IDMAP_CONV_IDTONAME:
639                 if (upcall->im_id != im->im_id)
640                         break;
641                 len = strlen(im->im_name);
642                 ret = nfs_idmap_instantiate(key, authkey, im->im_name, len);
643                 break;
644         default:
645                 ret = -EINVAL;
646         }
647 out:
648         return ret;
649 }
650 
651 static ssize_t
652 idmap_pipe_downcall(struct file *filp, const char __user *src, size_t mlen)
653 {
654         struct rpc_inode *rpci = RPC_I(file_inode(filp));
655         struct idmap *idmap = (struct idmap *)rpci->private;
656         struct key_construction *cons;
657         struct idmap_msg im;
658         size_t namelen_in;
659         int ret = -ENOKEY;
660 
661         /* If instantiation is successful, anyone waiting for key construction
662          * will have been woken up and someone else may now have used
663          * idmap_key_cons - so after this point we may no longer touch it.
664          */
665         if (idmap->idmap_upcall_data == NULL)
666                 goto out_noupcall;
667 
668         cons = idmap->idmap_upcall_data->key_cons;
669 
670         if (mlen != sizeof(im)) {
671                 ret = -ENOSPC;
672                 goto out;
673         }
674 
675         if (copy_from_user(&im, src, mlen) != 0) {
676                 ret = -EFAULT;
677                 goto out;
678         }
679 
680         if (!(im.im_status & IDMAP_STATUS_SUCCESS)) {
681                 ret = -ENOKEY;
682                 goto out;
683         }
684 
685         namelen_in = strnlen(im.im_name, IDMAP_NAMESZ);
686         if (namelen_in == 0 || namelen_in == IDMAP_NAMESZ) {
687                 ret = -EINVAL;
688                 goto out;
689 }
690 
691         ret = nfs_idmap_read_and_verify_message(&im,
692                         &idmap->idmap_upcall_data->idmap_msg,
693                         cons->key, cons->authkey);
694         if (ret >= 0) {
695                 key_set_timeout(cons->key, nfs_idmap_cache_timeout);
696                 ret = mlen;
697         }
698 
699 out:
700         nfs_idmap_complete_pipe_upcall_locked(idmap, ret);
701 out_noupcall:
702         return ret;
703 }
704 
705 static void
706 idmap_pipe_destroy_msg(struct rpc_pipe_msg *msg)
707 {
708         struct idmap_legacy_upcalldata *data = container_of(msg,
709                         struct idmap_legacy_upcalldata,
710                         pipe_msg);
711         struct idmap *idmap = data->idmap;
712 
713         if (msg->errno)
714                 nfs_idmap_abort_pipe_upcall(idmap, msg->errno);
715 }
716 
717 static void
718 idmap_release_pipe(struct inode *inode)
719 {
720         struct rpc_inode *rpci = RPC_I(inode);
721         struct idmap *idmap = (struct idmap *)rpci->private;
722 
723         nfs_idmap_abort_pipe_upcall(idmap, -EPIPE);
724 }
725 
726 int nfs_map_name_to_uid(const struct nfs_server *server, const char *name, size_t namelen, kuid_t *uid)
727 {
728         struct idmap *idmap = server->nfs_client->cl_idmap;
729         __u32 id = -1;
730         int ret = 0;
731 
732         if (!nfs_map_string_to_numeric(name, namelen, &id))
733                 ret = nfs_idmap_lookup_id(name, namelen, "uid", &id, idmap);
734         if (ret == 0) {
735                 *uid = make_kuid(&init_user_ns, id);
736                 if (!uid_valid(*uid))
737                         ret = -ERANGE;
738         }
739         trace_nfs4_map_name_to_uid(name, namelen, id, ret);
740         return ret;
741 }
742 
743 int nfs_map_group_to_gid(const struct nfs_server *server, const char *name, size_t namelen, kgid_t *gid)
744 {
745         struct idmap *idmap = server->nfs_client->cl_idmap;
746         __u32 id = -1;
747         int ret = 0;
748 
749         if (!nfs_map_string_to_numeric(name, namelen, &id))
750                 ret = nfs_idmap_lookup_id(name, namelen, "gid", &id, idmap);
751         if (ret == 0) {
752                 *gid = make_kgid(&init_user_ns, id);
753                 if (!gid_valid(*gid))
754                         ret = -ERANGE;
755         }
756         trace_nfs4_map_group_to_gid(name, namelen, id, ret);
757         return ret;
758 }
759 
760 int nfs_map_uid_to_name(const struct nfs_server *server, kuid_t uid, char *buf, size_t buflen)
761 {
762         struct idmap *idmap = server->nfs_client->cl_idmap;
763         int ret = -EINVAL;
764         __u32 id;
765 
766         id = from_kuid(&init_user_ns, uid);
767         if (!(server->caps & NFS_CAP_UIDGID_NOMAP))
768                 ret = nfs_idmap_lookup_name(id, "user", buf, buflen, idmap);
769         if (ret < 0)
770                 ret = nfs_map_numeric_to_string(id, buf, buflen);
771         trace_nfs4_map_uid_to_name(buf, ret, id, ret);
772         return ret;
773 }
774 int nfs_map_gid_to_group(const struct nfs_server *server, kgid_t gid, char *buf, size_t buflen)
775 {
776         struct idmap *idmap = server->nfs_client->cl_idmap;
777         int ret = -EINVAL;
778         __u32 id;
779 
780         id = from_kgid(&init_user_ns, gid);
781         if (!(server->caps & NFS_CAP_UIDGID_NOMAP))
782                 ret = nfs_idmap_lookup_name(id, "group", buf, buflen, idmap);
783         if (ret < 0)
784                 ret = nfs_map_numeric_to_string(id, buf, buflen);
785         trace_nfs4_map_gid_to_group(buf, ret, id, ret);
786         return ret;
787 }
788 

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