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10#include <linux/seq_file.h>
11#include <linux/pagemap.h>
12#include <linux/parser.h>
13#include <linux/magic.h>
14
15#include "autofs_i.h"
16
17struct autofs_info *autofs_new_ino(struct autofs_sb_info *sbi)
18{
19 struct autofs_info *ino;
20
21 ino = kzalloc(sizeof(*ino), GFP_KERNEL);
22 if (ino) {
23 INIT_LIST_HEAD(&ino->active);
24 INIT_LIST_HEAD(&ino->expiring);
25 ino->last_used = jiffies;
26 ino->sbi = sbi;
27 }
28 return ino;
29}
30
31void autofs_clean_ino(struct autofs_info *ino)
32{
33 ino->uid = GLOBAL_ROOT_UID;
34 ino->gid = GLOBAL_ROOT_GID;
35 ino->last_used = jiffies;
36}
37
38void autofs_free_ino(struct autofs_info *ino)
39{
40 kfree(ino);
41}
42
43void autofs_kill_sb(struct super_block *sb)
44{
45 struct autofs_sb_info *sbi = autofs_sbi(sb);
46
47
48
49
50
51
52
53 if (sbi) {
54
55 autofs_catatonic_mode(sbi);
56 put_pid(sbi->oz_pgrp);
57 }
58
59 pr_debug("shutting down\n");
60 kill_litter_super(sb);
61 if (sbi)
62 kfree_rcu(sbi, rcu);
63}
64
65static int autofs_show_options(struct seq_file *m, struct dentry *root)
66{
67 struct autofs_sb_info *sbi = autofs_sbi(root->d_sb);
68 struct inode *root_inode = d_inode(root->d_sb->s_root);
69
70 if (!sbi)
71 return 0;
72
73 seq_printf(m, ",fd=%d", sbi->pipefd);
74 if (!uid_eq(root_inode->i_uid, GLOBAL_ROOT_UID))
75 seq_printf(m, ",uid=%u",
76 from_kuid_munged(&init_user_ns, root_inode->i_uid));
77 if (!gid_eq(root_inode->i_gid, GLOBAL_ROOT_GID))
78 seq_printf(m, ",gid=%u",
79 from_kgid_munged(&init_user_ns, root_inode->i_gid));
80 seq_printf(m, ",pgrp=%d", pid_vnr(sbi->oz_pgrp));
81 seq_printf(m, ",timeout=%lu", sbi->exp_timeout/HZ);
82 seq_printf(m, ",minproto=%d", sbi->min_proto);
83 seq_printf(m, ",maxproto=%d", sbi->max_proto);
84
85 if (autofs_type_offset(sbi->type))
86 seq_printf(m, ",offset");
87 else if (autofs_type_direct(sbi->type))
88 seq_printf(m, ",direct");
89 else
90 seq_printf(m, ",indirect");
91 if (sbi->flags & AUTOFS_SBI_STRICTEXPIRE)
92 seq_printf(m, ",strictexpire");
93#ifdef CONFIG_CHECKPOINT_RESTORE
94 if (sbi->pipe)
95 seq_printf(m, ",pipe_ino=%ld", file_inode(sbi->pipe)->i_ino);
96 else
97 seq_printf(m, ",pipe_ino=-1");
98#endif
99 return 0;
100}
101
102static void autofs_evict_inode(struct inode *inode)
103{
104 clear_inode(inode);
105 kfree(inode->i_private);
106}
107
108static const struct super_operations autofs_sops = {
109 .statfs = simple_statfs,
110 .show_options = autofs_show_options,
111 .evict_inode = autofs_evict_inode,
112};
113
114enum {Opt_err, Opt_fd, Opt_uid, Opt_gid, Opt_pgrp, Opt_minproto, Opt_maxproto,
115 Opt_indirect, Opt_direct, Opt_offset, Opt_strictexpire};
116
117static const match_table_t tokens = {
118 {Opt_fd, "fd=%u"},
119 {Opt_uid, "uid=%u"},
120 {Opt_gid, "gid=%u"},
121 {Opt_pgrp, "pgrp=%u"},
122 {Opt_minproto, "minproto=%u"},
123 {Opt_maxproto, "maxproto=%u"},
124 {Opt_indirect, "indirect"},
125 {Opt_direct, "direct"},
126 {Opt_offset, "offset"},
127 {Opt_strictexpire, "strictexpire"},
128 {Opt_err, NULL}
129};
130
131static int parse_options(char *options,
132 struct inode *root, int *pgrp, bool *pgrp_set,
133 struct autofs_sb_info *sbi)
134{
135 char *p;
136 substring_t args[MAX_OPT_ARGS];
137 int option;
138 int pipefd = -1;
139 kuid_t uid;
140 kgid_t gid;
141
142 root->i_uid = current_uid();
143 root->i_gid = current_gid();
144
145 sbi->min_proto = AUTOFS_MIN_PROTO_VERSION;
146 sbi->max_proto = AUTOFS_MAX_PROTO_VERSION;
147
148 sbi->pipefd = -1;
149
150 if (!options)
151 return 1;
152
153 while ((p = strsep(&options, ",")) != NULL) {
154 int token;
155
156 if (!*p)
157 continue;
158
159 token = match_token(p, tokens, args);
160 switch (token) {
161 case Opt_fd:
162 if (match_int(args, &pipefd))
163 return 1;
164 sbi->pipefd = pipefd;
165 break;
166 case Opt_uid:
167 if (match_int(args, &option))
168 return 1;
169 uid = make_kuid(current_user_ns(), option);
170 if (!uid_valid(uid))
171 return 1;
172 root->i_uid = uid;
173 break;
174 case Opt_gid:
175 if (match_int(args, &option))
176 return 1;
177 gid = make_kgid(current_user_ns(), option);
178 if (!gid_valid(gid))
179 return 1;
180 root->i_gid = gid;
181 break;
182 case Opt_pgrp:
183 if (match_int(args, &option))
184 return 1;
185 *pgrp = option;
186 *pgrp_set = true;
187 break;
188 case Opt_minproto:
189 if (match_int(args, &option))
190 return 1;
191 sbi->min_proto = option;
192 break;
193 case Opt_maxproto:
194 if (match_int(args, &option))
195 return 1;
196 sbi->max_proto = option;
197 break;
198 case Opt_indirect:
199 set_autofs_type_indirect(&sbi->type);
200 break;
201 case Opt_direct:
202 set_autofs_type_direct(&sbi->type);
203 break;
204 case Opt_offset:
205 set_autofs_type_offset(&sbi->type);
206 break;
207 case Opt_strictexpire:
208 sbi->flags |= AUTOFS_SBI_STRICTEXPIRE;
209 break;
210 default:
211 return 1;
212 }
213 }
214 return (sbi->pipefd < 0);
215}
216
217int autofs_fill_super(struct super_block *s, void *data, int silent)
218{
219 struct inode *root_inode;
220 struct dentry *root;
221 struct file *pipe;
222 struct autofs_sb_info *sbi;
223 struct autofs_info *ino;
224 int pgrp = 0;
225 bool pgrp_set = false;
226 int ret = -EINVAL;
227
228 sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
229 if (!sbi)
230 return -ENOMEM;
231 pr_debug("starting up, sbi = %p\n", sbi);
232
233 s->s_fs_info = sbi;
234 sbi->magic = AUTOFS_SBI_MAGIC;
235 sbi->pipefd = -1;
236 sbi->pipe = NULL;
237 sbi->exp_timeout = 0;
238 sbi->oz_pgrp = NULL;
239 sbi->sb = s;
240 sbi->version = 0;
241 sbi->sub_version = 0;
242 sbi->flags = AUTOFS_SBI_CATATONIC;
243 set_autofs_type_indirect(&sbi->type);
244 sbi->min_proto = 0;
245 sbi->max_proto = 0;
246 mutex_init(&sbi->wq_mutex);
247 mutex_init(&sbi->pipe_mutex);
248 spin_lock_init(&sbi->fs_lock);
249 sbi->queues = NULL;
250 spin_lock_init(&sbi->lookup_lock);
251 INIT_LIST_HEAD(&sbi->active_list);
252 INIT_LIST_HEAD(&sbi->expiring_list);
253 s->s_blocksize = 1024;
254 s->s_blocksize_bits = 10;
255 s->s_magic = AUTOFS_SUPER_MAGIC;
256 s->s_op = &autofs_sops;
257 s->s_d_op = &autofs_dentry_operations;
258 s->s_time_gran = 1;
259
260
261
262
263 ino = autofs_new_ino(sbi);
264 if (!ino) {
265 ret = -ENOMEM;
266 goto fail_free;
267 }
268 root_inode = autofs_get_inode(s, S_IFDIR | 0755);
269 root = d_make_root(root_inode);
270 if (!root)
271 goto fail_ino;
272 pipe = NULL;
273
274 root->d_fsdata = ino;
275
276
277 if (parse_options(data, root_inode, &pgrp, &pgrp_set, sbi)) {
278 pr_err("called with bogus options\n");
279 goto fail_dput;
280 }
281
282
283 if (sbi->max_proto < AUTOFS_MIN_PROTO_VERSION ||
284 sbi->min_proto > AUTOFS_MAX_PROTO_VERSION) {
285 pr_err("kernel does not match daemon version "
286 "daemon (%d, %d) kernel (%d, %d)\n",
287 sbi->min_proto, sbi->max_proto,
288 AUTOFS_MIN_PROTO_VERSION, AUTOFS_MAX_PROTO_VERSION);
289 goto fail_dput;
290 }
291
292
293 if (sbi->max_proto > AUTOFS_MAX_PROTO_VERSION)
294 sbi->version = AUTOFS_MAX_PROTO_VERSION;
295 else
296 sbi->version = sbi->max_proto;
297 sbi->sub_version = AUTOFS_PROTO_SUBVERSION;
298
299 if (pgrp_set) {
300 sbi->oz_pgrp = find_get_pid(pgrp);
301 if (!sbi->oz_pgrp) {
302 pr_err("could not find process group %d\n",
303 pgrp);
304 goto fail_dput;
305 }
306 } else {
307 sbi->oz_pgrp = get_task_pid(current, PIDTYPE_PGID);
308 }
309
310 if (autofs_type_trigger(sbi->type))
311 __managed_dentry_set_managed(root);
312
313 root_inode->i_fop = &autofs_root_operations;
314 root_inode->i_op = &autofs_dir_inode_operations;
315
316 pr_debug("pipe fd = %d, pgrp = %u\n",
317 sbi->pipefd, pid_nr(sbi->oz_pgrp));
318 pipe = fget(sbi->pipefd);
319
320 if (!pipe) {
321 pr_err("could not open pipe file descriptor\n");
322 goto fail_put_pid;
323 }
324 ret = autofs_prepare_pipe(pipe);
325 if (ret < 0)
326 goto fail_fput;
327 sbi->pipe = pipe;
328 sbi->flags &= ~AUTOFS_SBI_CATATONIC;
329
330
331
332
333 s->s_root = root;
334 return 0;
335
336
337
338
339fail_fput:
340 pr_err("pipe file descriptor does not contain proper ops\n");
341 fput(pipe);
342fail_put_pid:
343 put_pid(sbi->oz_pgrp);
344fail_dput:
345 dput(root);
346 goto fail_free;
347fail_ino:
348 autofs_free_ino(ino);
349fail_free:
350 kfree(sbi);
351 s->s_fs_info = NULL;
352 return ret;
353}
354
355struct inode *autofs_get_inode(struct super_block *sb, umode_t mode)
356{
357 struct inode *inode = new_inode(sb);
358
359 if (inode == NULL)
360 return NULL;
361
362 inode->i_mode = mode;
363 if (sb->s_root) {
364 inode->i_uid = d_inode(sb->s_root)->i_uid;
365 inode->i_gid = d_inode(sb->s_root)->i_gid;
366 }
367 inode->i_atime = inode->i_mtime = inode->i_ctime = current_time(inode);
368 inode->i_ino = get_next_ino();
369
370 if (S_ISDIR(mode)) {
371 set_nlink(inode, 2);
372 inode->i_op = &autofs_dir_inode_operations;
373 inode->i_fop = &autofs_dir_operations;
374 } else if (S_ISLNK(mode)) {
375 inode->i_op = &autofs_symlink_inode_operations;
376 } else
377 WARN_ON(1);
378
379 return inode;
380}
381
