1
2
3
4
5
6
7
8
9
10#include <linux/kernel.h>
11#include <linux/slab.h>
12#include <linux/file.h>
13#include <linux/seq_file.h>
14#include <linux/pagemap.h>
15#include <linux/parser.h>
16#include <linux/bitops.h>
17#include <linux/magic.h>
18#include "autofs_i.h"
19#include <linux/module.h>
20
21struct autofs_info *autofs4_new_ino(struct autofs_sb_info *sbi)
22{
23 struct autofs_info *ino;
24
25 ino = kzalloc(sizeof(*ino), GFP_KERNEL);
26 if (ino) {
27 INIT_LIST_HEAD(&ino->active);
28 INIT_LIST_HEAD(&ino->expiring);
29 ino->last_used = jiffies;
30 ino->sbi = sbi;
31 }
32 return ino;
33}
34
35void autofs4_clean_ino(struct autofs_info *ino)
36{
37 ino->uid = GLOBAL_ROOT_UID;
38 ino->gid = GLOBAL_ROOT_GID;
39 ino->last_used = jiffies;
40}
41
42void autofs4_free_ino(struct autofs_info *ino)
43{
44 kfree(ino);
45}
46
47void autofs4_kill_sb(struct super_block *sb)
48{
49 struct autofs_sb_info *sbi = autofs4_sbi(sb);
50
51
52
53
54
55
56
57 if (sbi) {
58
59 autofs4_catatonic_mode(sbi);
60 put_pid(sbi->oz_pgrp);
61 }
62
63 pr_debug("shutting down\n");
64 kill_litter_super(sb);
65 if (sbi)
66 kfree_rcu(sbi, rcu);
67}
68
69static int autofs4_show_options(struct seq_file *m, struct dentry *root)
70{
71 struct autofs_sb_info *sbi = autofs4_sbi(root->d_sb);
72 struct inode *root_inode = d_inode(root->d_sb->s_root);
73
74 if (!sbi)
75 return 0;
76
77 seq_printf(m, ",fd=%d", sbi->pipefd);
78 if (!uid_eq(root_inode->i_uid, GLOBAL_ROOT_UID))
79 seq_printf(m, ",uid=%u",
80 from_kuid_munged(&init_user_ns, root_inode->i_uid));
81 if (!gid_eq(root_inode->i_gid, GLOBAL_ROOT_GID))
82 seq_printf(m, ",gid=%u",
83 from_kgid_munged(&init_user_ns, root_inode->i_gid));
84 seq_printf(m, ",pgrp=%d", pid_vnr(sbi->oz_pgrp));
85 seq_printf(m, ",timeout=%lu", sbi->exp_timeout/HZ);
86 seq_printf(m, ",minproto=%d", sbi->min_proto);
87 seq_printf(m, ",maxproto=%d", sbi->max_proto);
88
89 if (autofs_type_offset(sbi->type))
90 seq_printf(m, ",offset");
91 else if (autofs_type_direct(sbi->type))
92 seq_printf(m, ",direct");
93 else
94 seq_printf(m, ",indirect");
95#ifdef CONFIG_CHECKPOINT_RESTORE
96 if (sbi->pipe)
97 seq_printf(m, ",pipe_ino=%ld", file_inode(sbi->pipe)->i_ino);
98 else
99 seq_printf(m, ",pipe_ino=-1");
100#endif
101 return 0;
102}
103
104static void autofs4_evict_inode(struct inode *inode)
105{
106 clear_inode(inode);
107 kfree(inode->i_private);
108}
109
110static const struct super_operations autofs4_sops = {
111 .statfs = simple_statfs,
112 .show_options = autofs4_show_options,
113 .evict_inode = autofs4_evict_inode,
114};
115
116enum {Opt_err, Opt_fd, Opt_uid, Opt_gid, Opt_pgrp, Opt_minproto, Opt_maxproto,
117 Opt_indirect, Opt_direct, Opt_offset};
118
119static const match_table_t tokens = {
120 {Opt_fd, "fd=%u"},
121 {Opt_uid, "uid=%u"},
122 {Opt_gid, "gid=%u"},
123 {Opt_pgrp, "pgrp=%u"},
124 {Opt_minproto, "minproto=%u"},
125 {Opt_maxproto, "maxproto=%u"},
126 {Opt_indirect, "indirect"},
127 {Opt_direct, "direct"},
128 {Opt_offset, "offset"},
129 {Opt_err, NULL}
130};
131
132static int parse_options(char *options, int *pipefd, kuid_t *uid, kgid_t *gid,
133 int *pgrp, bool *pgrp_set, unsigned int *type,
134 int *minproto, int *maxproto)
135{
136 char *p;
137 substring_t args[MAX_OPT_ARGS];
138 int option;
139
140 *uid = current_uid();
141 *gid = current_gid();
142
143 *minproto = AUTOFS_MIN_PROTO_VERSION;
144 *maxproto = AUTOFS_MAX_PROTO_VERSION;
145
146 *pipefd = -1;
147
148 if (!options)
149 return 1;
150
151 while ((p = strsep(&options, ",")) != NULL) {
152 int token;
153
154 if (!*p)
155 continue;
156
157 token = match_token(p, tokens, args);
158 switch (token) {
159 case Opt_fd:
160 if (match_int(args, pipefd))
161 return 1;
162 break;
163 case Opt_uid:
164 if (match_int(args, &option))
165 return 1;
166 *uid = make_kuid(current_user_ns(), option);
167 if (!uid_valid(*uid))
168 return 1;
169 break;
170 case Opt_gid:
171 if (match_int(args, &option))
172 return 1;
173 *gid = make_kgid(current_user_ns(), option);
174 if (!gid_valid(*gid))
175 return 1;
176 break;
177 case Opt_pgrp:
178 if (match_int(args, &option))
179 return 1;
180 *pgrp = option;
181 *pgrp_set = true;
182 break;
183 case Opt_minproto:
184 if (match_int(args, &option))
185 return 1;
186 *minproto = option;
187 break;
188 case Opt_maxproto:
189 if (match_int(args, &option))
190 return 1;
191 *maxproto = option;
192 break;
193 case Opt_indirect:
194 set_autofs_type_indirect(type);
195 break;
196 case Opt_direct:
197 set_autofs_type_direct(type);
198 break;
199 case Opt_offset:
200 set_autofs_type_offset(type);
201 break;
202 default:
203 return 1;
204 }
205 }
206 return (*pipefd < 0);
207}
208
209int autofs4_fill_super(struct super_block *s, void *data, int silent)
210{
211 struct inode *root_inode;
212 struct dentry *root;
213 struct file *pipe;
214 int pipefd;
215 struct autofs_sb_info *sbi;
216 struct autofs_info *ino;
217 int pgrp = 0;
218 bool pgrp_set = false;
219 int ret = -EINVAL;
220
221 sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
222 if (!sbi)
223 return -ENOMEM;
224 pr_debug("starting up, sbi = %p\n", sbi);
225
226 s->s_fs_info = sbi;
227 sbi->magic = AUTOFS_SBI_MAGIC;
228 sbi->pipefd = -1;
229 sbi->pipe = NULL;
230 sbi->catatonic = 1;
231 sbi->exp_timeout = 0;
232 sbi->oz_pgrp = NULL;
233 sbi->sb = s;
234 sbi->version = 0;
235 sbi->sub_version = 0;
236 set_autofs_type_indirect(&sbi->type);
237 sbi->min_proto = 0;
238 sbi->max_proto = 0;
239 mutex_init(&sbi->wq_mutex);
240 mutex_init(&sbi->pipe_mutex);
241 spin_lock_init(&sbi->fs_lock);
242 sbi->queues = NULL;
243 spin_lock_init(&sbi->lookup_lock);
244 INIT_LIST_HEAD(&sbi->active_list);
245 INIT_LIST_HEAD(&sbi->expiring_list);
246 s->s_blocksize = 1024;
247 s->s_blocksize_bits = 10;
248 s->s_magic = AUTOFS_SUPER_MAGIC;
249 s->s_op = &autofs4_sops;
250 s->s_d_op = &autofs4_dentry_operations;
251 s->s_time_gran = 1;
252
253
254
255
256 ino = autofs4_new_ino(sbi);
257 if (!ino) {
258 ret = -ENOMEM;
259 goto fail_free;
260 }
261 root_inode = autofs4_get_inode(s, S_IFDIR | 0755);
262 root = d_make_root(root_inode);
263 if (!root)
264 goto fail_ino;
265 pipe = NULL;
266
267 root->d_fsdata = ino;
268
269
270 if (parse_options(data, &pipefd, &root_inode->i_uid, &root_inode->i_gid,
271 &pgrp, &pgrp_set, &sbi->type, &sbi->min_proto,
272 &sbi->max_proto)) {
273 pr_err("called with bogus options\n");
274 goto fail_dput;
275 }
276
277
278 if (sbi->max_proto < AUTOFS_MIN_PROTO_VERSION ||
279 sbi->min_proto > AUTOFS_MAX_PROTO_VERSION) {
280 pr_err("kernel does not match daemon version "
281 "daemon (%d, %d) kernel (%d, %d)\n",
282 sbi->min_proto, sbi->max_proto,
283 AUTOFS_MIN_PROTO_VERSION, AUTOFS_MAX_PROTO_VERSION);
284 goto fail_dput;
285 }
286
287
288 if (sbi->max_proto > AUTOFS_MAX_PROTO_VERSION)
289 sbi->version = AUTOFS_MAX_PROTO_VERSION;
290 else
291 sbi->version = sbi->max_proto;
292 sbi->sub_version = AUTOFS_PROTO_SUBVERSION;
293
294 if (pgrp_set) {
295 sbi->oz_pgrp = find_get_pid(pgrp);
296 if (!sbi->oz_pgrp) {
297 pr_err("could not find process group %d\n",
298 pgrp);
299 goto fail_dput;
300 }
301 } else {
302 sbi->oz_pgrp = get_task_pid(current, PIDTYPE_PGID);
303 }
304
305 if (autofs_type_trigger(sbi->type))
306 __managed_dentry_set_managed(root);
307
308 root_inode->i_fop = &autofs4_root_operations;
309 root_inode->i_op = &autofs4_dir_inode_operations;
310
311 pr_debug("pipe fd = %d, pgrp = %u\n", pipefd, pid_nr(sbi->oz_pgrp));
312 pipe = fget(pipefd);
313
314 if (!pipe) {
315 pr_err("could not open pipe file descriptor\n");
316 goto fail_put_pid;
317 }
318 ret = autofs_prepare_pipe(pipe);
319 if (ret < 0)
320 goto fail_fput;
321 sbi->pipe = pipe;
322 sbi->pipefd = pipefd;
323 sbi->catatonic = 0;
324
325
326
327
328 s->s_root = root;
329 return 0;
330
331
332
333
334fail_fput:
335 pr_err("pipe file descriptor does not contain proper ops\n");
336 fput(pipe);
337fail_put_pid:
338 put_pid(sbi->oz_pgrp);
339fail_dput:
340 dput(root);
341 goto fail_free;
342fail_ino:
343 autofs4_free_ino(ino);
344fail_free:
345 kfree(sbi);
346 s->s_fs_info = NULL;
347 return ret;
348}
349
350struct inode *autofs4_get_inode(struct super_block *sb, umode_t mode)
351{
352 struct inode *inode = new_inode(sb);
353
354 if (inode == NULL)
355 return NULL;
356
357 inode->i_mode = mode;
358 if (sb->s_root) {
359 inode->i_uid = d_inode(sb->s_root)->i_uid;
360 inode->i_gid = d_inode(sb->s_root)->i_gid;
361 }
362 inode->i_atime = inode->i_mtime = inode->i_ctime = current_time(inode);
363 inode->i_ino = get_next_ino();
364
365 if (S_ISDIR(mode)) {
366 set_nlink(inode, 2);
367 inode->i_op = &autofs4_dir_inode_operations;
368 inode->i_fop = &autofs4_dir_operations;
369 } else if (S_ISLNK(mode)) {
370 inode->i_op = &autofs4_symlink_inode_operations;
371 } else
372 WARN_ON(1);
373
374 return inode;
375}
376
