1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * fs/hmdfs/inode_local.c
4  *
5  * Copyright (c) 2020-2021 Huawei Device Co., Ltd.
6  */
7 
8 #include <linux/file.h>
9 #include <linux/fs_stack.h>
10 #include <linux/kernel.h>
11 #include <linux/mount.h>
12 #include <linux/namei.h>
13 #include <linux/string.h>
14 
15 #include "authority/authentication.h"
16 #include "comm/socket_adapter.h"
17 #include "comm/transport.h"
18 #include "hmdfs_client.h"
19 #include "hmdfs_dentryfile.h"
20 #include "hmdfs_device_view.h"
21 #include "hmdfs_share.h"
22 #include "hmdfs_trace.h"
23 
24 extern struct kmem_cache *hmdfs_dentry_cachep;
25 
26 struct hmdfs_name_data {
27 	struct dir_context ctx;
28 	const struct qstr *to_find;
29 	char *name;
30 	bool found;
31 };
32 
init_hmdfs_dentry_info(struct hmdfs_sb_info *sbi, struct dentry *dentry, int dentry_type)33 int init_hmdfs_dentry_info(struct hmdfs_sb_info *sbi, struct dentry *dentry,
34 			   int dentry_type)
35 {
36 	struct hmdfs_dentry_info *info =
37 		kmem_cache_zalloc(hmdfs_dentry_cachep, GFP_ATOMIC);
38 
39 	if (!info)
40 		return -ENOMEM;
41 	INIT_LIST_HEAD(&info->cache_list_head);
42 	INIT_LIST_HEAD(&info->remote_cache_list_head);
43 	spin_lock_init(&info->cache_list_lock);
44 	mutex_init(&info->remote_cache_list_lock);
45 	mutex_init(&info->cache_pull_lock);
46 	spin_lock_init(&info->lock);
47 	info->dentry_type = dentry_type;
48 	info->device_id = 0;
49 	dentry->d_fsdata = info;
50 	if (dentry_type == HMDFS_LAYER_ZERO ||
51 	    dentry_type == HMDFS_LAYER_FIRST_DEVICE ||
52 	    dentry_type == HMDFS_LAYER_SECOND_LOCAL ||
53 	    dentry_type == HMDFS_LAYER_SECOND_CLOUD ||
54 	    dentry_type == HMDFS_LAYER_SECOND_REMOTE)
55 		d_set_d_op(dentry, &hmdfs_dev_dops);
56 	else
57 		d_set_d_op(dentry, &hmdfs_dops);
58 	return 0;
59 }
60 
set_sharefile_flag(struct hmdfs_dentry_info *gdi)61 static inline void set_sharefile_flag(struct hmdfs_dentry_info *gdi)
62 {
63 	gdi->file_type = HM_SHARE;
64 }
65 
check_and_fixup_share_ops(struct inode *inode, const char *name)66 static void check_and_fixup_share_ops(struct inode *inode,
67 					const char *name)
68 {
69 	if (is_share_dir(inode, name)) {
70 		inode->i_op = &hmdfs_dir_inode_ops_share;
71 		inode->i_fop = &hmdfs_dir_ops_share;
72 	}
73 }
74 
fill_inode_local(struct super_block *sb, struct inode *lower_inode, const char *name)75 struct inode *fill_inode_local(struct super_block *sb,
76 			       struct inode *lower_inode, const char *name)
77 {
78 	int ret = 0;
79 	struct inode *inode;
80 	struct hmdfs_sb_info *sbi = hmdfs_sb(sb);
81 	struct hmdfs_inode_info *info;
82 
83 	if (!igrab(lower_inode))
84 		return ERR_PTR(-ESTALE);
85 
86 	inode = hmdfs_iget5_locked_local(sb, lower_inode);
87 	if (!inode) {
88 		hmdfs_err("iget5_locked get inode NULL");
89 		iput(lower_inode);
90 		return ERR_PTR(-ENOMEM);
91 	}
92 	if (!(inode->i_state & I_NEW)) {
93 		iput(lower_inode);
94 		return inode;
95 	}
96 
97 	info = hmdfs_i(inode);
98 #ifdef CONFIG_HMDFS_FS_PERMISSION
99 	info->perm = hmdfs_read_perm(lower_inode);
100 #endif
101 	if (S_ISDIR(lower_inode->i_mode))
102 		inode->i_mode = (lower_inode->i_mode & S_IFMT) | S_IRWXU |
103 				S_IRWXG | S_IXOTH;
104 	else if (S_ISREG(lower_inode->i_mode))
105 		inode->i_mode = (lower_inode->i_mode & S_IFMT) | S_IRUSR |
106 				S_IWUSR | S_IRGRP | S_IWGRP;
107 	else if (S_ISLNK(lower_inode->i_mode))
108 		inode->i_mode =
109 			S_IFREG | S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP;
110 
111 #ifdef CONFIG_HMDFS_FS_PERMISSION
112 	inode->i_uid = lower_inode->i_uid;
113 	inode->i_gid = lower_inode->i_gid;
114 #else
115 	inode->i_uid = KUIDT_INIT((uid_t)1000);
116 	inode->i_gid = KGIDT_INIT((gid_t)1000);
117 #endif
118 	inode->i_atime = lower_inode->i_atime;
119 	inode->__i_ctime = lower_inode->__i_ctime;
120 	inode->i_mtime = lower_inode->i_mtime;
121 	inode->i_generation = lower_inode->i_generation;
122 
123 	info->inode_type = HMDFS_LAYER_OTHER_LOCAL;
124 	if (S_ISDIR(lower_inode->i_mode)) {
125 		inode->i_op = &hmdfs_dir_inode_ops_local;
126 		inode->i_fop = &hmdfs_dir_ops_local;
127 		inode->i_mode |= S_IXUGO;
128 	} else if (S_ISREG(lower_inode->i_mode)) {
129 		inode->i_op = &hmdfs_file_iops_local;
130 		inode->i_fop = &hmdfs_file_fops_local;
131 	} else if (S_ISLNK(lower_inode->i_mode)) {
132 		inode->i_op = &hmdfs_symlink_iops_local;
133 		inode->i_fop = &hmdfs_file_fops_local;
134 		inode->i_size = i_size_read(lower_inode);
135 	} else {
136 		ret = -EIO;
137 		goto bad_inode;
138 	}
139 
140 	if (sbi->s_cloud_disk_switch)
141 		inode->i_mapping->a_ops = &hmdfs_aops_cloud;
142 
143 	fsstack_copy_inode_size(inode, lower_inode);
144 	check_and_fixup_share_ops(inode, name);
145 	unlock_new_inode(inode);
146 	return inode;
147 bad_inode:
148 	iget_failed(inode);
149 	return ERR_PTR(ret);
150 }
151 
152 /* hmdfs_convert_lookup_flags - covert hmdfs lookup flags to vfs lookup flags
153  *
154  * @hmdfs_flags: hmdfs lookup flags
155  * @vfs_flags: pointer to converted flags
156  *
157  * return 0 on success, or err code on failure.
158  */
hmdfs_convert_lookup_flags(unsigned int hmdfs_flags, unsigned int *vfs_flags)159 int hmdfs_convert_lookup_flags(unsigned int hmdfs_flags,
160 			       unsigned int *vfs_flags)
161 {
162 	*vfs_flags = 0;
163 
164 	/* currently only support HMDFS_LOOKUP_REVAL */
165 	if (hmdfs_flags & ~HMDFS_LOOKUP_REVAL)
166 		return -EINVAL;
167 
168 	if (hmdfs_flags & HMDFS_LOOKUP_REVAL)
169 		*vfs_flags |= LOOKUP_REVAL;
170 
171 	return 0;
172 }
173 
hmdfs_name_match(struct dir_context *ctx, const char *name, int namelen, loff_t offset, u64 ino, unsigned int d_type)174 static bool hmdfs_name_match(struct dir_context *ctx, const char *name,
175 			    int namelen, loff_t offset, u64 ino,
176 			    unsigned int d_type)
177 {
178 	struct hmdfs_name_data *buf =
179 		container_of(ctx, struct hmdfs_name_data, ctx);
180 	struct qstr candidate = QSTR_INIT(name, namelen);
181 
182 	if (qstr_case_eq(buf->to_find, &candidate)) {
183 		memcpy(buf->name, name, namelen);
184 		buf->name[namelen] = 0;
185 		buf->found = true;
186 		return false;
187 	}
188 	return true;
189 }
190 
__lookup_nosensitive(struct path *lower_parent_path, struct dentry *child_dentry, unsigned int flags, struct path *lower_path)191 static int __lookup_nosensitive(struct path *lower_parent_path,
192 				struct dentry *child_dentry, unsigned int flags,
193 				struct path *lower_path)
194 {
195 	struct file *file;
196 	const struct cred *cred = current_cred();
197 	const struct qstr *name = &child_dentry->d_name;
198 	int err;
199 	struct hmdfs_name_data buffer = {
200 		.ctx.actor = hmdfs_name_match,
201 		.to_find = name,
202 		.name = __getname(),
203 		.found = false,
204 	};
205 
206 	if (!buffer.name) {
207 		err = -ENOMEM;
208 		goto out;
209 	}
210 	file = dentry_open(lower_parent_path, O_RDONLY, cred);
211 	if (IS_ERR(file)) {
212 		err = PTR_ERR(file);
213 		goto put_name;
214 	}
215 	err = iterate_dir(file, &buffer.ctx);
216 	fput(file);
217 	if (err)
218 		goto put_name;
219 	if (buffer.found)
220 		err = vfs_path_lookup(lower_parent_path->dentry,
221 				      lower_parent_path->mnt, buffer.name,
222 				      flags, lower_path);
223 	else
224 		err = -ENOENT;
225 put_name:
226 	__putname(buffer.name);
227 out:
228 	return err;
229 }
230 
set_symlink_flag(struct hmdfs_dentry_info *gdi)231 static inline void set_symlink_flag(struct hmdfs_dentry_info *gdi)
232 {
233 	gdi->file_type = HM_SYMLINK;
234 }
235 
hmdfs_lookup_local(struct inode *parent_inode, struct dentry *child_dentry, unsigned int flags)236 struct dentry *hmdfs_lookup_local(struct inode *parent_inode,
237 				  struct dentry *child_dentry,
238 				  unsigned int flags)
239 {
240 	const char *d_name = child_dentry->d_name.name;
241 	int err = 0;
242 	struct path lower_path, lower_parent_path;
243 	struct dentry *lower_dentry = NULL, *parent_dentry = NULL, *ret = NULL;
244 	struct hmdfs_dentry_info *gdi = NULL;
245 	struct inode *child_inode = NULL;
246 	struct hmdfs_sb_info *sbi = hmdfs_sb(child_dentry->d_sb);
247 
248 	trace_hmdfs_lookup_local(parent_inode, child_dentry, flags);
249 	if (child_dentry->d_name.len > NAME_MAX) {
250 		ret = ERR_PTR(-ENAMETOOLONG);
251 		goto out;
252 	}
253 
254 	/* local device */
255 	parent_dentry = dget_parent(child_dentry);
256 	hmdfs_get_lower_path(parent_dentry, &lower_parent_path);
257 	err = init_hmdfs_dentry_info(sbi, child_dentry,
258 				     HMDFS_LAYER_OTHER_LOCAL);
259 	if (err) {
260 		ret = ERR_PTR(err);
261 		goto out_err;
262 	}
263 
264 	gdi = hmdfs_d(child_dentry);
265 
266 	flags &= ~LOOKUP_FOLLOW;
267 	err = vfs_path_lookup(lower_parent_path.dentry, lower_parent_path.mnt,
268 			      (child_dentry->d_name.name), 0, &lower_path);
269 	if (err && err != -ENOENT) {
270 		ret = ERR_PTR(err);
271 		goto out_err;
272 	} else if (!err) {
273 		hmdfs_set_lower_path(child_dentry, &lower_path);
274 		child_inode = fill_inode_local(parent_inode->i_sb,
275 					       d_inode(lower_path.dentry),
276 						   child_dentry->d_name.name);
277 
278 		if (S_ISLNK(d_inode(lower_path.dentry)->i_mode))
279 			set_symlink_flag(gdi);
280 		if (IS_ERR(child_inode)) {
281 			err = PTR_ERR(child_inode);
282 			ret = ERR_PTR(err);
283 			hmdfs_put_reset_lower_path(child_dentry);
284 			goto out_err;
285 		}
286 		ret = d_splice_alias(child_inode, child_dentry);
287 		if (IS_ERR(ret)) {
288 			err = PTR_ERR(ret);
289 			hmdfs_put_reset_lower_path(child_dentry);
290 			goto out_err;
291 		}
292 
293 		check_and_fixup_ownership(parent_inode, child_inode);
294 		goto out_err;
295 	}
296 	/*
297 	 * return 0 here, so that vfs can continue the process of making this
298 	 * negative dentry to a positive one while creating a new file.
299 	 */
300 	err = 0;
301 	ret = 0;
302 
303 	lower_dentry = lookup_one_len_unlocked(d_name, lower_parent_path.dentry,
304 					       child_dentry->d_name.len);
305 	if (IS_ERR(lower_dentry)) {
306 		err = PTR_ERR(lower_dentry);
307 		ret = lower_dentry;
308 		goto out_err;
309 	}
310 	lower_path.dentry = lower_dentry;
311 	lower_path.mnt = mntget(lower_parent_path.mnt);
312 	hmdfs_set_lower_path(child_dentry, &lower_path);
313 
314 out_err:
315 	if (!err)
316 		hmdfs_set_time(child_dentry, jiffies);
317 	hmdfs_put_lower_path(&lower_parent_path);
318 	dput(parent_dentry);
319 out:
320 	trace_hmdfs_lookup_local_end(parent_inode, child_dentry, err);
321 	return ret;
322 }
323 
hmdfs_mkdir_local_dentry(struct inode *dir, struct dentry *dentry, umode_t mode)324 int hmdfs_mkdir_local_dentry(struct inode *dir, struct dentry *dentry,
325 			     umode_t mode)
326 {
327 	struct inode *lower_dir = hmdfs_i(dir)->lower_inode;
328 	struct dentry *lower_dir_dentry = NULL;
329 	struct super_block *sb = dir->i_sb;
330 	struct path lower_path;
331 	struct dentry *lower_dentry = NULL;
332 	int error = 0;
333 	struct inode *lower_inode = NULL;
334 	struct inode *child_inode = NULL;
335 	bool local_res = false;
336 	struct cache_fs_override or;
337 	__u16 child_perm;
338 	kuid_t tmp_uid;
339 
340 	error = hmdfs_override_dir_id_fs(&or, dir, dentry, &child_perm);
341 	if (error)
342 		goto cleanup;
343 
344 	hmdfs_get_lower_path(dentry, &lower_path);
345 	lower_dentry = lower_path.dentry;
346 	lower_dir_dentry = lock_parent(lower_dentry);
347 
348 	tmp_uid = hmdfs_override_inode_uid(lower_dir);
349 	mode = (mode & S_IFMT) | 00771;
350 
351 	error = vfs_mkdir(&nop_mnt_idmap, lower_dir, lower_dentry, mode);
352 	hmdfs_revert_inode_uid(lower_dir, tmp_uid);
353 	if (error) {
354 		hmdfs_err("vfs_mkdir() error:%d", error);
355 		goto out;
356 	}
357 	local_res = true;
358 	lower_inode = d_inode(lower_dentry);
359 #ifdef CONFIG_HMDFS_FS_PERMISSION
360 	error = hmdfs_persist_perm(lower_dentry, &child_perm);
361 #endif
362 	child_inode = fill_inode_local(sb, lower_inode, dentry->d_name.name);
363 	if (IS_ERR(child_inode)) {
364 		error = PTR_ERR(child_inode);
365 		goto out;
366 	}
367 	d_add(dentry, child_inode);
368 	set_nlink(dir, hmdfs_i(dir)->lower_inode->i_nlink);
369 out:
370 	unlock_dir(lower_dir_dentry);
371 	if (local_res)
372 		hmdfs_drop_remote_cache_dents(dentry->d_parent);
373 
374 	if (error) {
375 		hmdfs_clear_drop_flag(dentry->d_parent);
376 		d_drop(dentry);
377 	}
378 	hmdfs_put_lower_path(&lower_path);
379 	hmdfs_revert_dir_id_fs(&or);
380 cleanup:
381 	return error;
382 }
383 
hmdfs_mkdir_local(struct mnt_idmap *idmap, struct inode *dir, struct dentry *dentry, umode_t mode)384 int hmdfs_mkdir_local(struct mnt_idmap *idmap, struct inode *dir, struct dentry *dentry, umode_t mode)
385 {
386 	int err = 0;
387 
388 	if (check_filename(dentry->d_name.name, dentry->d_name.len)) {
389 		err = -EINVAL;
390 		return err;
391 	}
392 
393 	if (hmdfs_file_type(dentry->d_name.name) != HMDFS_TYPE_COMMON) {
394 		err = -EACCES;
395 		return err;
396 	}
397 	err = hmdfs_mkdir_local_dentry(dir, dentry, mode);
398 	trace_hmdfs_mkdir_local(dir, dentry, err);
399 	return err;
400 }
401 
hmdfs_create_local_dentry(struct inode *dir, struct dentry *dentry, umode_t mode, bool want_excl)402 int hmdfs_create_local_dentry(struct inode *dir, struct dentry *dentry,
403 			      umode_t mode, bool want_excl)
404 {
405 	struct inode *lower_dir = NULL;
406 	struct dentry *lower_dir_dentry = NULL;
407 	struct super_block *sb = dir->i_sb;
408 	struct path lower_path;
409 	struct dentry *lower_dentry = NULL;
410 	int error = 0;
411 	struct inode *lower_inode = NULL;
412 	struct inode *child_inode = NULL;
413 	kuid_t tmp_uid;
414 #ifdef CONFIG_HMDFS_FS_PERMISSION
415 	const struct cred *saved_cred = NULL;
416 	struct fs_struct *saved_fs = NULL, *copied_fs = NULL;
417 	__u16 child_perm;
418 #endif
419 
420 #ifdef CONFIG_HMDFS_FS_PERMISSION
421 	saved_cred = hmdfs_override_file_fsids(dir, &child_perm);
422 	if (!saved_cred) {
423 		error = -ENOMEM;
424 		goto path_err;
425 	}
426 
427 	saved_fs = current->fs;
428 	copied_fs = hmdfs_override_fsstruct(saved_fs);
429 	if (!copied_fs) {
430 		error = -ENOMEM;
431 		goto revert_fsids;
432 	}
433 #endif
434 	hmdfs_get_lower_path(dentry, &lower_path);
435 	lower_dentry = lower_path.dentry;
436 	mode = (mode & S_IFMT) | 00660;
437 	lower_dir_dentry = lock_parent(lower_dentry);
438 	lower_dir = d_inode(lower_dir_dentry);
439 	tmp_uid = hmdfs_override_inode_uid(lower_dir);
440 	error = vfs_create(&nop_mnt_idmap, lower_dir, lower_dentry, mode, want_excl);
441 	hmdfs_revert_inode_uid(lower_dir, tmp_uid);
442 	unlock_dir(lower_dir_dentry);
443 	if (error)
444 		goto out;
445 
446 	lower_inode = d_inode(lower_dentry);
447 #ifdef CONFIG_HMDFS_FS_PERMISSION
448 	error = hmdfs_persist_perm(lower_dentry, &child_perm);
449 #endif
450 	child_inode = fill_inode_local(sb, lower_inode, dentry->d_name.name);
451 	if (IS_ERR(child_inode)) {
452 		error = PTR_ERR(child_inode);
453 		goto out_created;
454 	}
455 	d_add(dentry, child_inode);
456 
457 out_created:
458 	hmdfs_drop_remote_cache_dents(dentry->d_parent);
459 out:
460 	if (error) {
461 		hmdfs_clear_drop_flag(dentry->d_parent);
462 		d_drop(dentry);
463 	}
464 	hmdfs_put_lower_path(&lower_path);
465 
466 #ifdef CONFIG_HMDFS_FS_PERMISSION
467 	hmdfs_revert_fsstruct(saved_fs, copied_fs);
468 revert_fsids:
469 	hmdfs_revert_fsids(saved_cred);
470 #endif
471 #ifdef CONFIG_HMDFS_FS_PERMISSION
472 path_err:
473 #endif
474 	return error;
475 }
476 
hmdfs_create_local(struct mnt_idmap *idmap, struct inode *dir, struct dentry *child_dentry, umode_t mode, bool want_excl)477 int hmdfs_create_local(struct mnt_idmap *idmap, struct inode *dir, struct dentry *child_dentry,
478 		       umode_t mode, bool want_excl)
479 {
480 	int err = 0;
481 
482 	if (check_filename(child_dentry->d_name.name,
483 			   child_dentry->d_name.len)) {
484 		err = -EINVAL;
485 		return err;
486 	}
487 
488 	if (hmdfs_file_type(child_dentry->d_name.name) != HMDFS_TYPE_COMMON) {
489 		err = -EACCES;
490 		return err;
491 	}
492 
493 	err = hmdfs_create_local_dentry(dir, child_dentry, mode, want_excl);
494 	trace_hmdfs_create_local(dir, child_dentry, err);
495 	return err;
496 }
497 
hmdfs_rmdir_local_dentry(struct inode *dir, struct dentry *dentry)498 int hmdfs_rmdir_local_dentry(struct inode *dir, struct dentry *dentry)
499 {
500 	struct inode *lower_dir = NULL;
501 	struct dentry *lower_dir_dentry = NULL;
502 	kuid_t tmp_uid;
503 	struct path lower_path;
504 	struct dentry *lower_dentry = NULL;
505 	struct dentry *lookup_dentry = NULL;
506 	int error = 0;
507 
508 	hmdfs_clear_cache_dents(dentry, true);
509 	hmdfs_get_lower_path(dentry, &lower_path);
510 	lower_dentry = lower_path.dentry;
511 	lower_dir_dentry = lock_parent(lower_dentry);
512 	lower_dir = d_inode(lower_dir_dentry);
513 
514 	lookup_dentry = lookup_one_len(lower_dentry->d_name.name, lower_dir_dentry,
515 				       lower_dentry->d_name.len);
516 	if (IS_ERR(lookup_dentry)) {
517 		error = PTR_ERR(lookup_dentry);
518 		hmdfs_err("lookup_one_len failed, err = %d", error);
519 		goto lookup_err;
520 	}
521 	tmp_uid = hmdfs_override_inode_uid(lower_dir);
522 
523 	error = vfs_rmdir(&nop_mnt_idmap, lower_dir, lookup_dentry);
524 	hmdfs_revert_inode_uid(lower_dir, tmp_uid);
525 	dput(lookup_dentry);
526 lookup_err:
527 	unlock_dir(lower_dir_dentry);
528 	hmdfs_put_lower_path(&lower_path);
529 	if (error)
530 		goto path_err;
531 	hmdfs_drop_remote_cache_dents(dentry->d_parent);
532 path_err:
533 	if (error)
534 		hmdfs_clear_drop_flag(dentry->d_parent);
535 	return error;
536 }
537 
hmdfs_rmdir_local(struct inode *dir, struct dentry *dentry)538 int hmdfs_rmdir_local(struct inode *dir, struct dentry *dentry)
539 {
540 	int err = 0;
541 
542 	if (hmdfs_file_type(dentry->d_name.name) != HMDFS_TYPE_COMMON) {
543 		err = -EACCES;
544 		goto out;
545 	}
546 
547 	err = hmdfs_rmdir_local_dentry(dir, dentry);
548 	if (err != 0) {
549 		hmdfs_err("rm dir failed:%d", err);
550 		goto out;
551 	}
552 
553 	/* drop dentry even remote failed
554 	 * it maybe cause that one remote devices disconnect
555 	 * when doing remote rmdir
556 	 */
557 	d_drop(dentry);
558 out:
559 	/* return connect device's errcode */
560 	trace_hmdfs_rmdir_local(dir, dentry, err);
561 	return err;
562 }
563 
hmdfs_unlink_local_dentry(struct inode *dir, struct dentry *dentry)564 int hmdfs_unlink_local_dentry(struct inode *dir, struct dentry *dentry)
565 {
566 	struct dentry *lower_dir_dentry = NULL;
567 	struct path lower_path;
568 	struct inode *lower_dir = NULL;
569 	struct dentry *lower_dentry = NULL;
570 	struct dentry *lookup_dentry = NULL;
571 	int error;
572 	kuid_t tmp_uid;
573 
574 	hmdfs_get_lower_path(dentry, &lower_path);
575 	lower_dentry = lower_path.dentry;
576 	dget(lower_dentry);
577 	lower_dir_dentry = lock_parent(lower_dentry);
578 	lower_dir = d_inode(lower_dir_dentry);
579 	lookup_dentry = lookup_one_len(lower_dentry->d_name.name, lower_dir_dentry,
580 				       lower_dentry->d_name.len);
581 	if (IS_ERR(lookup_dentry)) {
582 		error = PTR_ERR(lookup_dentry);
583 		hmdfs_err("lookup_one_len failed, err = %d", error);
584 		goto lookup_err;
585 	}
586 
587 	tmp_uid = hmdfs_override_inode_uid(lower_dir);
588 	error = vfs_unlink(&nop_mnt_idmap, lower_dir, lookup_dentry, NULL);
589 	hmdfs_revert_inode_uid(lower_dir, tmp_uid);
590 	set_nlink(d_inode(dentry),
591 		  hmdfs_i(d_inode(dentry))->lower_inode->i_nlink);
592 	dput(lookup_dentry);
593 lookup_err:
594 	unlock_dir(lower_dir_dentry);
595 	dput(lower_dentry);
596 	if (error)
597 		goto path_err;
598 
599 	hmdfs_drop_remote_cache_dents(dentry->d_parent);
600 	d_drop(dentry);
601 
602 path_err:
603 	hmdfs_put_lower_path(&lower_path);
604 	if (error)
605 		hmdfs_clear_drop_flag(dentry->d_parent);
606 	return error;
607 }
608 
hmdfs_unlink_local(struct inode *dir, struct dentry *dentry)609 int hmdfs_unlink_local(struct inode *dir, struct dentry *dentry)
610 {
611 	if (hmdfs_file_type(dentry->d_name.name) != HMDFS_TYPE_COMMON)
612 		return -EACCES;
613 
614 	return hmdfs_unlink_local_dentry(dir, dentry);
615 }
616 
hmdfs_rename_local_dentry(struct inode *old_dir, struct dentry *old_dentry, struct inode *new_dir, struct dentry *new_dentry, unsigned int flags)617 int hmdfs_rename_local_dentry(struct inode *old_dir, struct dentry *old_dentry,
618 			      struct inode *new_dir, struct dentry *new_dentry,
619 			      unsigned int flags)
620 {
621 	struct path lower_old_path;
622 	struct path lower_new_path;
623 	struct dentry *lower_old_dentry = NULL;
624 	struct dentry *lower_new_dentry = NULL;
625 	struct dentry *lower_old_dir_dentry = NULL;
626 	struct dentry *lower_new_dir_dentry = NULL;
627 	struct dentry *trap = NULL;
628 	struct renamedata rename_data;
629 	int rc = 0;
630 	kuid_t old_dir_uid, new_dir_uid;
631 
632 	if (flags)
633 		return -EINVAL;
634 
635 	hmdfs_get_lower_path(old_dentry, &lower_old_path);
636 	lower_old_dentry = lower_old_path.dentry;
637 	if (!lower_old_dentry) {
638 		hmdfs_err("lower_old_dentry as NULL");
639 		rc = -EACCES;
640 		goto out_put_old_path;
641 	}
642 
643 	hmdfs_get_lower_path(new_dentry, &lower_new_path);
644 	lower_new_dentry = lower_new_path.dentry;
645 	if (!lower_new_dentry) {
646 		hmdfs_err("lower_new_dentry as NULL");
647 		rc = -EACCES;
648 		goto out_put_new_path;
649 	}
650 
651 	lower_old_dir_dentry = dget_parent(lower_old_dentry);
652 	lower_new_dir_dentry = dget_parent(lower_new_dentry);
653 	trap = lock_rename(lower_old_dir_dentry, lower_new_dir_dentry);
654 	new_dir_uid = hmdfs_override_inode_uid(d_inode(lower_new_dir_dentry));
655 	old_dir_uid = hmdfs_override_inode_uid(d_inode(lower_old_dir_dentry));
656 
657 	/* source should not be ancestor of target */
658 	if (trap == lower_old_dentry) {
659 		rc = -EINVAL;
660 		goto out_lock;
661 	}
662 	/* target should not be ancestor of source */
663 	if (trap == lower_new_dentry) {
664 		rc = -ENOTEMPTY;
665 		goto out_lock;
666 	}
667 
668 	rename_data.old_mnt_idmap = &nop_mnt_idmap;
669 	rename_data.old_dir = d_inode(lower_old_dir_dentry);
670 	rename_data.old_dentry = lower_old_dentry;
671 	rename_data.new_mnt_idmap = &nop_mnt_idmap;
672 	rename_data.new_dir = d_inode(lower_new_dir_dentry);
673 	rename_data.new_dentry = lower_new_dentry;
674 	rename_data.flags = flags;
675 	rc = vfs_rename(&rename_data);
676 
677 out_lock:
678 	dget(old_dentry);
679 
680 	hmdfs_revert_inode_uid(d_inode(lower_old_dir_dentry), old_dir_uid);
681 	hmdfs_revert_inode_uid(d_inode(lower_new_dir_dentry), new_dir_uid);
682 
683 	unlock_rename(lower_old_dir_dentry, lower_new_dir_dentry);
684 	if (rc == 0) {
685 		hmdfs_drop_remote_cache_dents(old_dentry->d_parent);
686 		if (old_dentry->d_parent != new_dentry->d_parent)
687 			hmdfs_drop_remote_cache_dents(new_dentry->d_parent);
688 	} else {
689 		hmdfs_clear_drop_flag(old_dentry->d_parent);
690 		if (old_dentry->d_parent != new_dentry->d_parent)
691 			hmdfs_clear_drop_flag(old_dentry->d_parent);
692 		d_drop(new_dentry);
693 	}
694 
695 	dput(old_dentry);
696 	dput(lower_old_dir_dentry);
697 	dput(lower_new_dir_dentry);
698 
699 out_put_new_path:
700 	hmdfs_put_lower_path(&lower_new_path);
701 out_put_old_path:
702 	hmdfs_put_lower_path(&lower_old_path);
703 	return rc;
704 }
705 
hmdfs_rename_local(struct mnt_idmap *idmap, struct inode *old_dir, struct dentry *old_dentry, struct inode *new_dir, struct dentry *new_dentry, unsigned int flags)706 int hmdfs_rename_local(struct mnt_idmap *idmap, struct inode *old_dir, struct dentry *old_dentry,
707 		       struct inode *new_dir, struct dentry *new_dentry,
708 		       unsigned int flags)
709 {
710 	int err = 0;
711 	int ret = 0;
712 
713 	trace_hmdfs_rename_local(old_dir, old_dentry, new_dir, new_dentry,
714 				 flags);
715 	if (hmdfs_file_type(old_dentry->d_name.name) != HMDFS_TYPE_COMMON ||
716 	    hmdfs_file_type(new_dentry->d_name.name) != HMDFS_TYPE_COMMON) {
717 		err = -EACCES;
718 		goto rename_out;
719 	}
720 
721 	if (hmdfs_i(old_dir)->inode_type != hmdfs_i(new_dir)->inode_type) {
722 		hmdfs_err("in different view");
723 		err = -EPERM;
724 		goto rename_out;
725 	}
726 
727 	if (hmdfs_d(old_dentry)->device_id != hmdfs_d(new_dentry)->device_id) {
728 		err = -EXDEV;
729 		goto rename_out;
730 	}
731 
732 	if (S_ISREG(old_dentry->d_inode->i_mode)) {
733 		err = hmdfs_rename_local_dentry(old_dir, old_dentry, new_dir,
734 						new_dentry, flags);
735 	} else if (S_ISDIR(old_dentry->d_inode->i_mode)) {
736 		ret = hmdfs_rename_local_dentry(old_dir, old_dentry, new_dir,
737 						new_dentry, flags);
738 		if (ret != 0) {
739 			err = ret;
740 			goto rename_out;
741 		}
742 	}
743 
744 	if (!err)
745 		d_invalidate(old_dentry);
746 
747 rename_out:
748 	return err;
749 }
750 
symname_is_allowed(const char *symname)751 static bool symname_is_allowed(const char *symname)
752 {
753 	char *p = NULL;
754 	size_t len;
755 
756 	len = strnlen(symname, PATH_MAX);
757 	if (len >= PATH_MAX)
758 		return false;
759 
760 	p = strstr(symname, "/../");
761 	if (p)
762 		return false;
763 
764 	if (len == 2u && strncmp(symname, "..", 2u) == 0)
765 		return false;
766 	if (len >= 3u && strncmp(symname, "../", 3u) == 0)
767 		return false;
768 	if (len >= 3u && strncmp(symname + len - 3u, "/..", 3u) == 0)
769 		return false;
770 	return true;
771 }
772 
hmdfs_symlink_local(struct mnt_idmap *idmap, struct inode *dir, struct dentry *dentry, const char *symname)773 int hmdfs_symlink_local(struct mnt_idmap *idmap, struct inode *dir, struct dentry *dentry,
774 			const char *symname)
775 {
776 	int err;
777 	struct dentry *lower_dentry = NULL;
778 	struct dentry *lower_parent_dentry = NULL;
779 	struct path lower_path;
780 	struct inode *child_inode = NULL;
781 	struct inode *lower_dir_inode = hmdfs_i(dir)->lower_inode;
782 	struct hmdfs_dentry_info *gdi = hmdfs_d(dentry);
783 	kuid_t tmp_uid;
784 #ifdef CONFIG_HMDFS_FS_PERMISSION
785 	const struct cred *saved_cred = NULL;
786 	struct fs_struct *saved_fs = NULL, *copied_fs = NULL;
787 	__u16 child_perm;
788 #endif
789 
790 	if (unlikely(!symname_is_allowed(symname))) {
791 		err = -EPERM;
792 		goto path_err;
793 	}
794 
795 #ifdef CONFIG_HMDFS_FS_PERMISSION
796 	saved_cred = hmdfs_override_file_fsids(dir, &child_perm);
797 	if (!saved_cred) {
798 		err = -ENOMEM;
799 		goto path_err;
800 	}
801 
802 	saved_fs = current->fs;
803 	copied_fs = hmdfs_override_fsstruct(saved_fs);
804 	if (!copied_fs) {
805 		err = -ENOMEM;
806 		goto revert_fsids;
807 	}
808 #endif
809 	hmdfs_get_lower_path(dentry, &lower_path);
810 	lower_dentry = lower_path.dentry;
811 	lower_parent_dentry = lock_parent(lower_dentry);
812 	tmp_uid = hmdfs_override_inode_uid(lower_dir_inode);
813 	err = vfs_symlink(&nop_mnt_idmap, lower_dir_inode, lower_dentry, symname);
814 	hmdfs_revert_inode_uid(lower_dir_inode, tmp_uid);
815 	unlock_dir(lower_parent_dentry);
816 	if (err)
817 		goto out_err;
818 	set_symlink_flag(gdi);
819 #ifdef CONFIG_HMDFS_FS_PERMISSION
820 	err = hmdfs_persist_perm(lower_dentry, &child_perm);
821 #endif
822 	child_inode = fill_inode_local(dir->i_sb, d_inode(lower_dentry),
823 				       dentry->d_name.name);
824 	if (IS_ERR(child_inode)) {
825 		err = PTR_ERR(child_inode);
826 		goto out_err;
827 	}
828 	d_add(dentry, child_inode);
829 	fsstack_copy_attr_times(dir, lower_dir_inode);
830 	fsstack_copy_inode_size(dir, lower_dir_inode);
831 
832 out_err:
833 	hmdfs_put_lower_path(&lower_path);
834 #ifdef CONFIG_HMDFS_FS_PERMISSION
835 	hmdfs_revert_fsstruct(saved_fs, copied_fs);
836 revert_fsids:
837 	hmdfs_revert_fsids(saved_cred);
838 #endif
839 path_err:
840 	return err;
841 }
842 
hmdfs_get_link_local(struct dentry *dentry, struct inode *inode, struct delayed_call *done)843 static const char *hmdfs_get_link_local(struct dentry *dentry,
844 					struct inode *inode,
845 					struct delayed_call *done)
846 {
847 	const char *link = NULL;
848 	struct dentry *lower_dentry = NULL;
849 	struct inode *lower_inode = NULL;
850 	struct path lower_path;
851 
852 	if(!dentry) {
853 		hmdfs_err("dentry MULL");
854 		link = ERR_PTR(-ECHILD);
855 		goto link_out;
856 	}
857 
858 	hmdfs_get_lower_path(dentry, &lower_path);
859 	lower_dentry = lower_path.dentry;
860 	lower_inode = d_inode(lower_dentry);
861 	if(!lower_inode->i_op || !lower_inode->i_op->get_link) {
862 		hmdfs_err("The lower inode doesn't support get_link i_op");
863 		link = ERR_PTR(-EINVAL);
864 		goto out;
865 	}
866 
867 	link = lower_inode->i_op->get_link(lower_dentry, lower_inode, done);
868 	if(IS_ERR_OR_NULL(link))
869 		goto out;
870 	fsstack_copy_attr_atime(inode, lower_inode);
871 out:
872 	hmdfs_put_lower_path(&lower_path);
873 link_out:
874 	return link;
875 }
876 
hmdfs_setattr_local(struct mnt_idmap *idmap, struct dentry *dentry, struct iattr *ia)877 static int hmdfs_setattr_local(struct mnt_idmap *idmap, struct dentry *dentry, struct iattr *ia)
878 {
879 	struct inode *inode = d_inode(dentry);
880 	struct inode *lower_inode = hmdfs_i(inode)->lower_inode;
881 	struct path lower_path;
882 	struct dentry *lower_dentry = NULL;
883 	struct iattr lower_ia;
884 	unsigned int ia_valid = ia->ia_valid;
885 	int err = 0;
886 	kuid_t tmp_uid;
887 
888 	hmdfs_get_lower_path(dentry, &lower_path);
889 	lower_dentry = lower_path.dentry;
890 	memcpy(&lower_ia, ia, sizeof(lower_ia));
891 	if (ia_valid & ATTR_FILE)
892 		lower_ia.ia_file = hmdfs_f(ia->ia_file)->lower_file;
893 	lower_ia.ia_valid &= ~(ATTR_UID | ATTR_GID | ATTR_MODE);
894 	if (ia_valid & ATTR_SIZE) {
895 		err = inode_newsize_ok(inode, ia->ia_size);
896 		if (err)
897 			goto out;
898 		truncate_setsize(inode, ia->ia_size);
899 	}
900 	inode_lock(lower_inode);
901 	tmp_uid = hmdfs_override_inode_uid(lower_inode);
902 
903 	err = notify_change(&nop_mnt_idmap, lower_dentry, &lower_ia, NULL);
904 	i_size_write(inode, i_size_read(lower_inode));
905 	inode->i_atime = lower_inode->i_atime;
906 	inode->i_mtime = lower_inode->i_mtime;
907 	inode->__i_ctime = lower_inode->__i_ctime;
908 	err = update_inode_to_dentry(dentry, inode);
909 	hmdfs_revert_inode_uid(lower_inode, tmp_uid);
910 
911 	inode_unlock(lower_inode);
912 out:
913 	hmdfs_put_lower_path(&lower_path);
914 	return err;
915 }
916 
hmdfs_getattr_local(struct mnt_idmap *idmap, const struct path *path, struct kstat *stat, u32 request_mask, unsigned int flags)917 static int hmdfs_getattr_local(struct mnt_idmap *idmap, const struct path *path, struct kstat *stat,
918 			       u32 request_mask, unsigned int flags)
919 {
920 	struct path lower_path;
921 	int ret;
922 
923 	if (path->dentry == NULL || hmdfs_d(path->dentry) == NULL) {
924 		hmdfs_err("dentry is NULL");
925 		return -ENOENT;
926 	}
927 
928 	hmdfs_get_lower_path(path->dentry, &lower_path);
929 	ret = vfs_getattr(&lower_path, stat, request_mask, flags);
930 	stat->ino = d_inode(path->dentry)->i_ino;
931 	stat->uid = d_inode(path->dentry)->i_uid;
932 	stat->gid = d_inode(path->dentry)->i_gid;
933 	stat->dev = 0;
934 	stat->rdev = 0;
935 	hmdfs_put_lower_path(&lower_path);
936 
937 	return ret;
938 }
939 
hmdfs_permission(struct mnt_idmap *idmap, struct inode *inode, int mask)940 int hmdfs_permission(struct mnt_idmap *idmap, struct inode *inode, int mask)
941 {
942 #ifdef CONFIG_HMDFS_FS_PERMISSION
943 	unsigned int mode = inode->i_mode;
944 	kuid_t cur_uid = current_fsuid();
945 
946 	if (uid_eq(cur_uid, ROOT_UID) || uid_eq(cur_uid, SYSTEM_UID))
947 		return 0;
948 
949 	if (uid_eq(cur_uid, inode->i_uid)) {
950 		mode >>= 6;
951 	} else if (in_group_p(inode->i_gid)) {
952 		mode >>= 3;
953 	}
954 
955 	if ((mask & ~mode & (MAY_READ | MAY_WRITE | MAY_EXEC)) == 0)
956 		return 0;
957 
958 	trace_hmdfs_permission(inode->i_ino);
959 	return -EACCES;
960 #else
961 
962 	return 0;
963 #endif
964 }
965 
hmdfs_local_listxattr(struct dentry *dentry, char *list, size_t size)966 static ssize_t hmdfs_local_listxattr(struct dentry *dentry, char *list,
967 				     size_t size)
968 {
969 	struct path lower_path;
970 	ssize_t res = 0;
971 	size_t r_size = size;
972 
973 	if (!hmdfs_support_xattr(dentry))
974 		return -EOPNOTSUPP;
975 
976 	if (size > HMDFS_LISTXATTR_SIZE_MAX)
977 		r_size = HMDFS_LISTXATTR_SIZE_MAX;
978 
979 	hmdfs_get_lower_path(dentry, &lower_path);
980 	res = vfs_listxattr(lower_path.dentry, list, r_size);
981 	hmdfs_put_lower_path(&lower_path);
982 
983 	if (res == -ERANGE && r_size != size) {
984 		hmdfs_info("no support listxattr size over than %d",
985 			   HMDFS_LISTXATTR_SIZE_MAX);
986 		res = -E2BIG;
987 	}
988 
989 	return res;
990 }
hmdfs_lookup_share(struct inode *parent_inode, struct dentry *child_dentry, unsigned int flags)991 struct dentry *hmdfs_lookup_share(struct inode *parent_inode,
992 				struct dentry *child_dentry, unsigned int flags)
993 {
994 	const struct qstr *d_name = &child_dentry->d_name;
995 	int err = 0;
996 	struct dentry *ret = NULL;
997 	struct hmdfs_sb_info *sbi = hmdfs_sb(child_dentry->d_sb);
998 	struct path src_path;
999 	struct inode *child_inode = NULL;
1000 
1001 	trace_hmdfs_lookup_share(parent_inode, child_dentry, flags);
1002 	if (d_name->len > NAME_MAX) {
1003 		ret = ERR_PTR(-ENAMETOOLONG);
1004 		goto err_out;
1005 	}
1006 
1007 	err = init_hmdfs_dentry_info(sbi, child_dentry, HMDFS_LAYER_OTHER_LOCAL);
1008 	if (err) {
1009 		ret = ERR_PTR(err);
1010 		goto err_out;
1011 	}
1012 
1013 	err = get_path_from_share_table(sbi, child_dentry, &src_path);
1014 	if (err) {
1015 		ret = ERR_PTR(err);
1016 		goto err_out;
1017 	}
1018 
1019 	hmdfs_set_lower_path(child_dentry, &src_path);
1020 	child_inode = fill_inode_local(parent_inode->i_sb,
1021 					d_inode(src_path.dentry), d_name->name);
1022 
1023 	set_sharefile_flag(hmdfs_d(child_dentry));
1024 
1025 	if (IS_ERR(child_inode)) {
1026 		err = PTR_ERR(child_inode);
1027 		ret = ERR_PTR(err);
1028 		hmdfs_put_reset_lower_path(child_dentry);
1029 		goto err_out;
1030 	}
1031 	ret = d_splice_alias(child_inode, child_dentry);
1032 	if (IS_ERR(ret)) {
1033 		err = PTR_ERR(ret);
1034 		hmdfs_put_reset_lower_path(child_dentry);
1035 		goto err_out;
1036 	}
1037 
1038 	check_and_fixup_ownership(parent_inode, child_inode);
1039 
1040 err_out:
1041 	trace_hmdfs_lookup_share_end(parent_inode, child_dentry, err);
1042 	return ret;
1043 }
1044 
1045 const struct inode_operations hmdfs_dir_inode_ops_local = {
1046 	.lookup = hmdfs_lookup_local,
1047 	.mkdir = hmdfs_mkdir_local,
1048 	.create = hmdfs_create_local,
1049 	.rmdir = hmdfs_rmdir_local,
1050 	.unlink = hmdfs_unlink_local,
1051 	.symlink = hmdfs_symlink_local,
1052 	.rename = hmdfs_rename_local,
1053 	.permission = hmdfs_permission,
1054 	.setattr = hmdfs_setattr_local,
1055 	.getattr = hmdfs_getattr_local,
1056 };
1057 
1058 const struct inode_operations hmdfs_symlink_iops_local = {
1059 	.get_link = hmdfs_get_link_local,
1060 	.permission = hmdfs_permission,
1061 	.setattr = hmdfs_setattr_local,
1062 };
1063 
1064 const struct inode_operations hmdfs_dir_inode_ops_share = {
1065 	.lookup = hmdfs_lookup_share,
1066 	.permission = hmdfs_permission,
1067 };
1068 
1069 const struct inode_operations hmdfs_file_iops_local = {
1070 	.setattr = hmdfs_setattr_local,
1071 	.getattr = hmdfs_getattr_local,
1072 	.permission = hmdfs_permission,
1073 	.listxattr = hmdfs_local_listxattr,
1074 };
1075