xref: /linux/fs/ntfs3/inode.c (revision a33fb016)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  *
4  * Copyright (C) 2019-2021 Paragon Software GmbH, All rights reserved.
5  *
6  */
7 
8 #include <linux/buffer_head.h>
9 #include <linux/fs.h>
10 #include <linux/mpage.h>
11 #include <linux/namei.h>
12 #include <linux/nls.h>
13 #include <linux/uio.h>
14 #include <linux/writeback.h>
15 
16 #include "debug.h"
17 #include "ntfs.h"
18 #include "ntfs_fs.h"
19 
20 /*
21  * ntfs_read_mft - Read record and parse MFT.
22  */
ntfs_read_mft(struct inode * inode,const struct cpu_str * name,const struct MFT_REF * ref)23 static struct inode *ntfs_read_mft(struct inode *inode,
24 				   const struct cpu_str *name,
25 				   const struct MFT_REF *ref)
26 {
27 	int err = 0;
28 	struct ntfs_inode *ni = ntfs_i(inode);
29 	struct super_block *sb = inode->i_sb;
30 	struct ntfs_sb_info *sbi = sb->s_fs_info;
31 	mode_t mode = 0;
32 	struct ATTR_STD_INFO5 *std5 = NULL;
33 	struct ATTR_LIST_ENTRY *le;
34 	struct ATTRIB *attr;
35 	bool is_match = false;
36 	bool is_root = false;
37 	bool is_dir;
38 	unsigned long ino = inode->i_ino;
39 	u32 rp_fa = 0, asize, t32;
40 	u16 roff, rsize, names = 0, links = 0;
41 	const struct ATTR_FILE_NAME *fname = NULL;
42 	const struct INDEX_ROOT *root;
43 	struct REPARSE_DATA_BUFFER rp; // 0x18 bytes
44 	u64 t64;
45 	struct MFT_REC *rec;
46 	struct runs_tree *run;
47 	struct timespec64 ts;
48 
49 	inode->i_op = NULL;
50 	/* Setup 'uid' and 'gid' */
51 	inode->i_uid = sbi->options->fs_uid;
52 	inode->i_gid = sbi->options->fs_gid;
53 
54 	err = mi_init(&ni->mi, sbi, ino);
55 	if (err)
56 		goto out;
57 
58 	if (!sbi->mft.ni && ino == MFT_REC_MFT && !sb->s_root) {
59 		t64 = sbi->mft.lbo >> sbi->cluster_bits;
60 		t32 = bytes_to_cluster(sbi, MFT_REC_VOL * sbi->record_size);
61 		sbi->mft.ni = ni;
62 		init_rwsem(&ni->file.run_lock);
63 
64 		if (!run_add_entry(&ni->file.run, 0, t64, t32, true)) {
65 			err = -ENOMEM;
66 			goto out;
67 		}
68 	}
69 
70 	err = mi_read(&ni->mi, ino == MFT_REC_MFT);
71 
72 	if (err)
73 		goto out;
74 
75 	rec = ni->mi.mrec;
76 
77 	if (sbi->flags & NTFS_FLAGS_LOG_REPLAYING) {
78 		;
79 	} else if (ref->seq != rec->seq) {
80 		err = -EINVAL;
81 		ntfs_err(sb, "MFT: r=%lx, expect seq=%x instead of %x!", ino,
82 			 le16_to_cpu(ref->seq), le16_to_cpu(rec->seq));
83 		goto out;
84 	} else if (!is_rec_inuse(rec)) {
85 		err = -ESTALE;
86 		ntfs_err(sb, "Inode r=%x is not in use!", (u32)ino);
87 		goto out;
88 	}
89 
90 	if (le32_to_cpu(rec->total) != sbi->record_size) {
91 		/* Bad inode? */
92 		err = -EINVAL;
93 		goto out;
94 	}
95 
96 	if (!is_rec_base(rec)) {
97 		err = -EINVAL;
98 		goto out;
99 	}
100 
101 	/* Record should contain $I30 root. */
102 	is_dir = rec->flags & RECORD_FLAG_DIR;
103 
104 	/* MFT_REC_MFT is not a dir */
105 	if (is_dir && ino == MFT_REC_MFT) {
106 		err = -EINVAL;
107 		goto out;
108 	}
109 
110 	inode->i_generation = le16_to_cpu(rec->seq);
111 
112 	/* Enumerate all struct Attributes MFT. */
113 	le = NULL;
114 	attr = NULL;
115 
116 	/*
117 	 * To reduce tab pressure use goto instead of
118 	 * while( (attr = ni_enum_attr_ex(ni, attr, &le, NULL) ))
119 	 */
120 next_attr:
121 	run = NULL;
122 	err = -EINVAL;
123 	attr = ni_enum_attr_ex(ni, attr, &le, NULL);
124 	if (!attr)
125 		goto end_enum;
126 
127 	if (le && le->vcn) {
128 		/* This is non primary attribute segment. Ignore if not MFT. */
129 		if (ino != MFT_REC_MFT || attr->type != ATTR_DATA)
130 			goto next_attr;
131 
132 		run = &ni->file.run;
133 		asize = le32_to_cpu(attr->size);
134 		goto attr_unpack_run;
135 	}
136 
137 	roff = attr->non_res ? 0 : le16_to_cpu(attr->res.data_off);
138 	rsize = attr->non_res ? 0 : le32_to_cpu(attr->res.data_size);
139 	asize = le32_to_cpu(attr->size);
140 
141 	/*
142 	 * Really this check was done in 'ni_enum_attr_ex' -> ... 'mi_enum_attr'.
143 	 * There not critical to check this case again
144 	 */
145 	if (attr->name_len &&
146 	    sizeof(short) * attr->name_len + le16_to_cpu(attr->name_off) >
147 		    asize)
148 		goto out;
149 
150 	if (attr->non_res) {
151 		t64 = le64_to_cpu(attr->nres.alloc_size);
152 		if (le64_to_cpu(attr->nres.data_size) > t64 ||
153 		    le64_to_cpu(attr->nres.valid_size) > t64)
154 			goto out;
155 	}
156 
157 	switch (attr->type) {
158 	case ATTR_STD:
159 		if (attr->non_res ||
160 		    asize < sizeof(struct ATTR_STD_INFO) + roff ||
161 		    rsize < sizeof(struct ATTR_STD_INFO))
162 			goto out;
163 
164 		if (std5)
165 			goto next_attr;
166 
167 		std5 = Add2Ptr(attr, roff);
168 
169 #ifdef STATX_BTIME
170 		nt2kernel(std5->cr_time, &ni->i_crtime);
171 #endif
172 		nt2kernel(std5->a_time, &ts);
173 		inode_set_atime_to_ts(inode, ts);
174 		nt2kernel(std5->c_time, &ts);
175 		inode_set_ctime_to_ts(inode, ts);
176 		nt2kernel(std5->m_time, &ts);
177 		inode_set_mtime_to_ts(inode, ts);
178 
179 		ni->std_fa = std5->fa;
180 
181 		if (asize >= sizeof(struct ATTR_STD_INFO5) + roff &&
182 		    rsize >= sizeof(struct ATTR_STD_INFO5))
183 			ni->std_security_id = std5->security_id;
184 		goto next_attr;
185 
186 	case ATTR_LIST:
187 		if (attr->name_len || le || ino == MFT_REC_LOG)
188 			goto out;
189 
190 		err = ntfs_load_attr_list(ni, attr);
191 		if (err)
192 			goto out;
193 
194 		le = NULL;
195 		attr = NULL;
196 		goto next_attr;
197 
198 	case ATTR_NAME:
199 		if (attr->non_res || asize < SIZEOF_ATTRIBUTE_FILENAME + roff ||
200 		    rsize < SIZEOF_ATTRIBUTE_FILENAME)
201 			goto out;
202 
203 		names += 1;
204 		fname = Add2Ptr(attr, roff);
205 		if (fname->type == FILE_NAME_DOS)
206 			goto next_attr;
207 
208 		links += 1;
209 		if (name && name->len == fname->name_len &&
210 		    !ntfs_cmp_names_cpu(name, (struct le_str *)&fname->name_len,
211 					NULL, false))
212 			is_match = true;
213 
214 		goto next_attr;
215 
216 	case ATTR_DATA:
217 		if (is_dir) {
218 			/* Ignore data attribute in dir record. */
219 			goto next_attr;
220 		}
221 
222 		if (ino == MFT_REC_BADCLUST && !attr->non_res)
223 			goto next_attr;
224 
225 		if (attr->name_len &&
226 		    ((ino != MFT_REC_BADCLUST || !attr->non_res ||
227 		      attr->name_len != ARRAY_SIZE(BAD_NAME) ||
228 		      memcmp(attr_name(attr), BAD_NAME, sizeof(BAD_NAME))) &&
229 		     (ino != MFT_REC_SECURE || !attr->non_res ||
230 		      attr->name_len != ARRAY_SIZE(SDS_NAME) ||
231 		      memcmp(attr_name(attr), SDS_NAME, sizeof(SDS_NAME))))) {
232 			/* File contains stream attribute. Ignore it. */
233 			goto next_attr;
234 		}
235 
236 		if (is_attr_sparsed(attr))
237 			ni->std_fa |= FILE_ATTRIBUTE_SPARSE_FILE;
238 		else
239 			ni->std_fa &= ~FILE_ATTRIBUTE_SPARSE_FILE;
240 
241 		if (is_attr_compressed(attr))
242 			ni->std_fa |= FILE_ATTRIBUTE_COMPRESSED;
243 		else
244 			ni->std_fa &= ~FILE_ATTRIBUTE_COMPRESSED;
245 
246 		if (is_attr_encrypted(attr))
247 			ni->std_fa |= FILE_ATTRIBUTE_ENCRYPTED;
248 		else
249 			ni->std_fa &= ~FILE_ATTRIBUTE_ENCRYPTED;
250 
251 		if (!attr->non_res) {
252 			ni->i_valid = inode->i_size = rsize;
253 			inode_set_bytes(inode, rsize);
254 		}
255 
256 		mode = S_IFREG | (0777 & sbi->options->fs_fmask_inv);
257 
258 		if (!attr->non_res) {
259 			ni->ni_flags |= NI_FLAG_RESIDENT;
260 			goto next_attr;
261 		}
262 
263 		inode_set_bytes(inode, attr_ondisk_size(attr));
264 
265 		ni->i_valid = le64_to_cpu(attr->nres.valid_size);
266 		inode->i_size = le64_to_cpu(attr->nres.data_size);
267 		if (!attr->nres.alloc_size)
268 			goto next_attr;
269 
270 		run = ino == MFT_REC_BITMAP ? &sbi->used.bitmap.run :
271 					      &ni->file.run;
272 		break;
273 
274 	case ATTR_ROOT:
275 		if (attr->non_res)
276 			goto out;
277 
278 		root = Add2Ptr(attr, roff);
279 
280 		if (attr->name_len != ARRAY_SIZE(I30_NAME) ||
281 		    memcmp(attr_name(attr), I30_NAME, sizeof(I30_NAME)))
282 			goto next_attr;
283 
284 		if (root->type != ATTR_NAME ||
285 		    root->rule != NTFS_COLLATION_TYPE_FILENAME)
286 			goto out;
287 
288 		if (!is_dir)
289 			goto next_attr;
290 
291 		is_root = true;
292 		ni->ni_flags |= NI_FLAG_DIR;
293 
294 		err = indx_init(&ni->dir, sbi, attr, INDEX_MUTEX_I30);
295 		if (err)
296 			goto out;
297 
298 		mode = sb->s_root ?
299 			       (S_IFDIR | (0777 & sbi->options->fs_dmask_inv)) :
300 			       (S_IFDIR | 0777);
301 		goto next_attr;
302 
303 	case ATTR_ALLOC:
304 		if (!is_root || attr->name_len != ARRAY_SIZE(I30_NAME) ||
305 		    memcmp(attr_name(attr), I30_NAME, sizeof(I30_NAME)))
306 			goto next_attr;
307 
308 		inode->i_size = le64_to_cpu(attr->nres.data_size);
309 		ni->i_valid = le64_to_cpu(attr->nres.valid_size);
310 		inode_set_bytes(inode, le64_to_cpu(attr->nres.alloc_size));
311 
312 		run = &ni->dir.alloc_run;
313 		break;
314 
315 	case ATTR_BITMAP:
316 		if (ino == MFT_REC_MFT) {
317 			if (!attr->non_res)
318 				goto out;
319 #ifndef CONFIG_NTFS3_64BIT_CLUSTER
320 			/* 0x20000000 = 2^32 / 8 */
321 			if (le64_to_cpu(attr->nres.alloc_size) >= 0x20000000)
322 				goto out;
323 #endif
324 			run = &sbi->mft.bitmap.run;
325 			break;
326 		} else if (is_dir && attr->name_len == ARRAY_SIZE(I30_NAME) &&
327 			   !memcmp(attr_name(attr), I30_NAME,
328 				   sizeof(I30_NAME)) &&
329 			   attr->non_res) {
330 			run = &ni->dir.bitmap_run;
331 			break;
332 		}
333 		goto next_attr;
334 
335 	case ATTR_REPARSE:
336 		if (attr->name_len)
337 			goto next_attr;
338 
339 		rp_fa = ni_parse_reparse(ni, attr, &rp);
340 		switch (rp_fa) {
341 		case REPARSE_LINK:
342 			/*
343 			 * Normal symlink.
344 			 * Assume one unicode symbol == one utf8.
345 			 */
346 			inode->i_size = le16_to_cpu(rp.SymbolicLinkReparseBuffer
347 							    .PrintNameLength) /
348 					sizeof(u16);
349 			ni->i_valid = inode->i_size;
350 			/* Clear directory bit. */
351 			if (ni->ni_flags & NI_FLAG_DIR) {
352 				indx_clear(&ni->dir);
353 				memset(&ni->dir, 0, sizeof(ni->dir));
354 				ni->ni_flags &= ~NI_FLAG_DIR;
355 			} else {
356 				run_close(&ni->file.run);
357 			}
358 			mode = S_IFLNK | 0777;
359 			is_dir = false;
360 			if (attr->non_res) {
361 				run = &ni->file.run;
362 				goto attr_unpack_run; // Double break.
363 			}
364 			break;
365 
366 		case REPARSE_COMPRESSED:
367 			break;
368 
369 		case REPARSE_DEDUPLICATED:
370 			break;
371 		}
372 		goto next_attr;
373 
374 	case ATTR_EA_INFO:
375 		if (!attr->name_len &&
376 		    resident_data_ex(attr, sizeof(struct EA_INFO))) {
377 			ni->ni_flags |= NI_FLAG_EA;
378 			/*
379 			 * ntfs_get_wsl_perm updates inode->i_uid, inode->i_gid, inode->i_mode
380 			 */
381 			inode->i_mode = mode;
382 			ntfs_get_wsl_perm(inode);
383 			mode = inode->i_mode;
384 		}
385 		goto next_attr;
386 
387 	default:
388 		goto next_attr;
389 	}
390 
391 attr_unpack_run:
392 	roff = le16_to_cpu(attr->nres.run_off);
393 
394 	if (roff > asize) {
395 		err = -EINVAL;
396 		goto out;
397 	}
398 
399 	t64 = le64_to_cpu(attr->nres.svcn);
400 
401 	err = run_unpack_ex(run, sbi, ino, t64, le64_to_cpu(attr->nres.evcn),
402 			    t64, Add2Ptr(attr, roff), asize - roff);
403 	if (err < 0)
404 		goto out;
405 	err = 0;
406 	goto next_attr;
407 
408 end_enum:
409 
410 	if (!std5)
411 		goto out;
412 
413 	if (!is_match && name) {
414 		err = -ENOENT;
415 		goto out;
416 	}
417 
418 	if (std5->fa & FILE_ATTRIBUTE_READONLY)
419 		mode &= ~0222;
420 
421 	if (!names) {
422 		err = -EINVAL;
423 		goto out;
424 	}
425 
426 	if (names != le16_to_cpu(rec->hard_links)) {
427 		/* Correct minor error on the fly. Do not mark inode as dirty. */
428 		ntfs_inode_warn(inode, "Correct links count -> %u.", names);
429 		rec->hard_links = cpu_to_le16(names);
430 		ni->mi.dirty = true;
431 	}
432 
433 	set_nlink(inode, links);
434 
435 	if (S_ISDIR(mode)) {
436 		ni->std_fa |= FILE_ATTRIBUTE_DIRECTORY;
437 
438 		/*
439 		 * Dot and dot-dot should be included in count but was not
440 		 * included in enumeration.
441 		 * Usually a hard links to directories are disabled.
442 		 */
443 		inode->i_op = &ntfs_dir_inode_operations;
444 		inode->i_fop = unlikely(is_legacy_ntfs(sb)) ?
445 				       &ntfs_legacy_dir_operations :
446 				       &ntfs_dir_operations;
447 		ni->i_valid = 0;
448 	} else if (S_ISLNK(mode)) {
449 		ni->std_fa &= ~FILE_ATTRIBUTE_DIRECTORY;
450 		inode->i_op = &ntfs_link_inode_operations;
451 		inode->i_fop = NULL;
452 		inode_nohighmem(inode);
453 	} else if (S_ISREG(mode)) {
454 		ni->std_fa &= ~FILE_ATTRIBUTE_DIRECTORY;
455 		inode->i_op = &ntfs_file_inode_operations;
456 		inode->i_fop = unlikely(is_legacy_ntfs(sb)) ?
457 				       &ntfs_legacy_file_operations :
458 				       &ntfs_file_operations;
459 		inode->i_mapping->a_ops = is_compressed(ni) ? &ntfs_aops_cmpr :
460 							      &ntfs_aops;
461 		if (ino != MFT_REC_MFT)
462 			init_rwsem(&ni->file.run_lock);
463 	} else if (S_ISCHR(mode) || S_ISBLK(mode) || S_ISFIFO(mode) ||
464 		   S_ISSOCK(mode)) {
465 		inode->i_op = &ntfs_special_inode_operations;
466 		init_special_inode(inode, mode, inode->i_rdev);
467 	} else if (fname && fname->home.low == cpu_to_le32(MFT_REC_EXTEND) &&
468 		   fname->home.seq == cpu_to_le16(MFT_REC_EXTEND)) {
469 		/* Records in $Extend are not a files or general directories. */
470 		inode->i_op = &ntfs_file_inode_operations;
471 	} else {
472 		err = -EINVAL;
473 		goto out;
474 	}
475 
476 	if ((sbi->options->sys_immutable &&
477 	     (std5->fa & FILE_ATTRIBUTE_SYSTEM)) &&
478 	    !S_ISFIFO(mode) && !S_ISSOCK(mode) && !S_ISLNK(mode)) {
479 		inode->i_flags |= S_IMMUTABLE;
480 	} else {
481 		inode->i_flags &= ~S_IMMUTABLE;
482 	}
483 
484 	inode->i_mode = mode;
485 	if (!(ni->ni_flags & NI_FLAG_EA)) {
486 		/* If no xattr then no security (stored in xattr). */
487 		inode->i_flags |= S_NOSEC;
488 	}
489 
490 	if (ino == MFT_REC_MFT && !sb->s_root)
491 		sbi->mft.ni = NULL;
492 
493 	unlock_new_inode(inode);
494 
495 	return inode;
496 
497 out:
498 	if (ino == MFT_REC_MFT && !sb->s_root)
499 		sbi->mft.ni = NULL;
500 
501 	iget_failed(inode);
502 	return ERR_PTR(err);
503 }
504 
505 /*
506  * ntfs_test_inode
507  *
508  * Return: 1 if match.
509  */
ntfs_test_inode(struct inode * inode,void * data)510 static int ntfs_test_inode(struct inode *inode, void *data)
511 {
512 	struct MFT_REF *ref = data;
513 
514 	return ino_get(ref) == inode->i_ino;
515 }
516 
ntfs_set_inode(struct inode * inode,void * data)517 static int ntfs_set_inode(struct inode *inode, void *data)
518 {
519 	const struct MFT_REF *ref = data;
520 
521 	inode->i_ino = ino_get(ref);
522 	return 0;
523 }
524 
ntfs_iget5(struct super_block * sb,const struct MFT_REF * ref,const struct cpu_str * name)525 struct inode *ntfs_iget5(struct super_block *sb, const struct MFT_REF *ref,
526 			 const struct cpu_str *name)
527 {
528 	struct inode *inode;
529 
530 	inode = iget5_locked(sb, ino_get(ref), ntfs_test_inode, ntfs_set_inode,
531 			     (void *)ref);
532 	if (unlikely(!inode))
533 		return ERR_PTR(-ENOMEM);
534 
535 	/* If this is a freshly allocated inode, need to read it now. */
536 	if (inode->i_state & I_NEW)
537 		inode = ntfs_read_mft(inode, name, ref);
538 	else if (ref->seq != ntfs_i(inode)->mi.mrec->seq) {
539 		/*
540 		 * Sequence number is not expected.
541 		 * Looks like inode was reused but caller uses the old reference
542 		 */
543 		iput(inode);
544 		inode = ERR_PTR(-ESTALE);
545 	}
546 
547 	if (IS_ERR(inode))
548 		ntfs_set_state(sb->s_fs_info, NTFS_DIRTY_ERROR);
549 
550 	return inode;
551 }
552 
553 enum get_block_ctx {
554 	GET_BLOCK_GENERAL = 0,
555 	GET_BLOCK_WRITE_BEGIN = 1,
556 	GET_BLOCK_DIRECT_IO_R = 2,
557 	GET_BLOCK_DIRECT_IO_W = 3,
558 	GET_BLOCK_BMAP = 4,
559 };
560 
ntfs_get_block_vbo(struct inode * inode,u64 vbo,struct buffer_head * bh,int create,enum get_block_ctx ctx)561 static noinline int ntfs_get_block_vbo(struct inode *inode, u64 vbo,
562 				       struct buffer_head *bh, int create,
563 				       enum get_block_ctx ctx)
564 {
565 	struct super_block *sb = inode->i_sb;
566 	struct ntfs_sb_info *sbi = sb->s_fs_info;
567 	struct ntfs_inode *ni = ntfs_i(inode);
568 	struct folio *folio = bh->b_folio;
569 	u8 cluster_bits = sbi->cluster_bits;
570 	u32 block_size = sb->s_blocksize;
571 	u64 bytes, lbo, valid;
572 	u32 off;
573 	int err;
574 	CLST vcn, lcn, len;
575 	bool new;
576 
577 	/* Clear previous state. */
578 	clear_buffer_new(bh);
579 	clear_buffer_uptodate(bh);
580 
581 	if (is_resident(ni)) {
582 		bh->b_blocknr = RESIDENT_LCN;
583 		bh->b_size = block_size;
584 		if (!folio) {
585 			/* direct io (read) or bmap call */
586 			err = 0;
587 		} else {
588 			ni_lock(ni);
589 			err = attr_data_read_resident(ni, folio);
590 			ni_unlock(ni);
591 
592 			if (!err)
593 				set_buffer_uptodate(bh);
594 		}
595 		return err;
596 	}
597 
598 	vcn = vbo >> cluster_bits;
599 	off = vbo & sbi->cluster_mask;
600 	new = false;
601 
602 	err = attr_data_get_block(ni, vcn, 1, &lcn, &len, create ? &new : NULL,
603 				  create && sbi->cluster_size > PAGE_SIZE);
604 	if (err)
605 		goto out;
606 
607 	if (!len)
608 		return 0;
609 
610 	bytes = ((u64)len << cluster_bits) - off;
611 
612 	if (lcn >= sbi->used.bitmap.nbits) {
613 		/* This case includes resident/compressed/sparse. */
614 		if (!create) {
615 			if (bh->b_size > bytes)
616 				bh->b_size = bytes;
617 			return 0;
618 		}
619 		WARN_ON(1);
620 	}
621 
622 	if (new)
623 		set_buffer_new(bh);
624 
625 	lbo = ((u64)lcn << cluster_bits) + off;
626 
627 	set_buffer_mapped(bh);
628 	bh->b_bdev = sb->s_bdev;
629 	bh->b_blocknr = lbo >> sb->s_blocksize_bits;
630 
631 	valid = ni->i_valid;
632 
633 	if (ctx == GET_BLOCK_DIRECT_IO_W) {
634 		/* ntfs_direct_IO will update ni->i_valid. */
635 		if (vbo >= valid)
636 			set_buffer_new(bh);
637 	} else if (create) {
638 		/* Normal write. */
639 		if (bytes > bh->b_size)
640 			bytes = bh->b_size;
641 
642 		if (vbo >= valid)
643 			set_buffer_new(bh);
644 
645 		if (vbo + bytes > valid) {
646 			ni->i_valid = vbo + bytes;
647 			mark_inode_dirty(inode);
648 		}
649 	} else if (vbo >= valid) {
650 		/* Read out of valid data. */
651 		clear_buffer_mapped(bh);
652 	} else if (vbo + bytes <= valid) {
653 		/* Normal read. */
654 	} else if (vbo + block_size <= valid) {
655 		/* Normal short read. */
656 		bytes = block_size;
657 	} else {
658 		/*
659 		 * Read across valid size: vbo < valid && valid < vbo + block_size
660 		 */
661 		bytes = block_size;
662 
663 		if (folio) {
664 			u32 voff = valid - vbo;
665 
666 			bh->b_size = block_size;
667 			off = vbo & (PAGE_SIZE - 1);
668 			folio_set_bh(bh, folio, off);
669 
670 			if (bh_read(bh, 0) < 0) {
671 				err = -EIO;
672 				goto out;
673 			}
674 			folio_zero_segment(folio, off + voff, off + block_size);
675 		}
676 	}
677 
678 	if (bh->b_size > bytes)
679 		bh->b_size = bytes;
680 
681 #ifndef __LP64__
682 	if (ctx == GET_BLOCK_DIRECT_IO_W || ctx == GET_BLOCK_DIRECT_IO_R) {
683 		static_assert(sizeof(size_t) < sizeof(loff_t));
684 		if (bytes > 0x40000000u)
685 			bh->b_size = 0x40000000u;
686 	}
687 #endif
688 
689 	return 0;
690 
691 out:
692 	return err;
693 }
694 
ntfs_get_block(struct inode * inode,sector_t vbn,struct buffer_head * bh_result,int create)695 int ntfs_get_block(struct inode *inode, sector_t vbn,
696 		   struct buffer_head *bh_result, int create)
697 {
698 	return ntfs_get_block_vbo(inode, (u64)vbn << inode->i_blkbits,
699 				  bh_result, create, GET_BLOCK_GENERAL);
700 }
701 
ntfs_get_block_bmap(struct inode * inode,sector_t vsn,struct buffer_head * bh_result,int create)702 static int ntfs_get_block_bmap(struct inode *inode, sector_t vsn,
703 			       struct buffer_head *bh_result, int create)
704 {
705 	return ntfs_get_block_vbo(inode,
706 				  (u64)vsn << inode->i_sb->s_blocksize_bits,
707 				  bh_result, create, GET_BLOCK_BMAP);
708 }
709 
ntfs_bmap(struct address_space * mapping,sector_t block)710 static sector_t ntfs_bmap(struct address_space *mapping, sector_t block)
711 {
712 	return generic_block_bmap(mapping, block, ntfs_get_block_bmap);
713 }
714 
ntfs_read_folio(struct file * file,struct folio * folio)715 static int ntfs_read_folio(struct file *file, struct folio *folio)
716 {
717 	int err;
718 	struct address_space *mapping = folio->mapping;
719 	struct inode *inode = mapping->host;
720 	struct ntfs_inode *ni = ntfs_i(inode);
721 
722 	if (is_resident(ni)) {
723 		ni_lock(ni);
724 		err = attr_data_read_resident(ni, folio);
725 		ni_unlock(ni);
726 		if (err != E_NTFS_NONRESIDENT) {
727 			folio_unlock(folio);
728 			return err;
729 		}
730 	}
731 
732 	if (is_compressed(ni)) {
733 		ni_lock(ni);
734 		err = ni_readpage_cmpr(ni, folio);
735 		ni_unlock(ni);
736 		return err;
737 	}
738 
739 	/* Normal + sparse files. */
740 	return mpage_read_folio(folio, ntfs_get_block);
741 }
742 
ntfs_readahead(struct readahead_control * rac)743 static void ntfs_readahead(struct readahead_control *rac)
744 {
745 	struct address_space *mapping = rac->mapping;
746 	struct inode *inode = mapping->host;
747 	struct ntfs_inode *ni = ntfs_i(inode);
748 	u64 valid;
749 	loff_t pos;
750 
751 	if (is_resident(ni)) {
752 		/* No readahead for resident. */
753 		return;
754 	}
755 
756 	if (is_compressed(ni)) {
757 		/* No readahead for compressed. */
758 		return;
759 	}
760 
761 	valid = ni->i_valid;
762 	pos = readahead_pos(rac);
763 
764 	if (valid < i_size_read(inode) && pos <= valid &&
765 	    valid < pos + readahead_length(rac)) {
766 		/* Range cross 'valid'. Read it page by page. */
767 		return;
768 	}
769 
770 	mpage_readahead(rac, ntfs_get_block);
771 }
772 
ntfs_get_block_direct_IO_R(struct inode * inode,sector_t iblock,struct buffer_head * bh_result,int create)773 static int ntfs_get_block_direct_IO_R(struct inode *inode, sector_t iblock,
774 				      struct buffer_head *bh_result, int create)
775 {
776 	return ntfs_get_block_vbo(inode, (u64)iblock << inode->i_blkbits,
777 				  bh_result, create, GET_BLOCK_DIRECT_IO_R);
778 }
779 
ntfs_get_block_direct_IO_W(struct inode * inode,sector_t iblock,struct buffer_head * bh_result,int create)780 static int ntfs_get_block_direct_IO_W(struct inode *inode, sector_t iblock,
781 				      struct buffer_head *bh_result, int create)
782 {
783 	return ntfs_get_block_vbo(inode, (u64)iblock << inode->i_blkbits,
784 				  bh_result, create, GET_BLOCK_DIRECT_IO_W);
785 }
786 
ntfs_direct_IO(struct kiocb * iocb,struct iov_iter * iter)787 static ssize_t ntfs_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
788 {
789 	struct file *file = iocb->ki_filp;
790 	struct address_space *mapping = file->f_mapping;
791 	struct inode *inode = mapping->host;
792 	struct ntfs_inode *ni = ntfs_i(inode);
793 	loff_t vbo = iocb->ki_pos;
794 	loff_t end;
795 	int wr = iov_iter_rw(iter) & WRITE;
796 	size_t iter_count = iov_iter_count(iter);
797 	loff_t valid;
798 	ssize_t ret;
799 
800 	if (is_resident(ni)) {
801 		/* Switch to buffered write. */
802 		ret = 0;
803 		goto out;
804 	}
805 
806 	ret = blockdev_direct_IO(iocb, inode, iter,
807 				 wr ? ntfs_get_block_direct_IO_W :
808 				      ntfs_get_block_direct_IO_R);
809 
810 	if (ret > 0)
811 		end = vbo + ret;
812 	else if (wr && ret == -EIOCBQUEUED)
813 		end = vbo + iter_count;
814 	else
815 		goto out;
816 
817 	valid = ni->i_valid;
818 	if (wr) {
819 		if (end > valid && !S_ISBLK(inode->i_mode)) {
820 			ni->i_valid = end;
821 			mark_inode_dirty(inode);
822 		}
823 	} else if (vbo < valid && valid < end) {
824 		/* Fix page. */
825 		iov_iter_revert(iter, end - valid);
826 		iov_iter_zero(end - valid, iter);
827 	}
828 
829 out:
830 	return ret;
831 }
832 
ntfs_set_size(struct inode * inode,u64 new_size)833 int ntfs_set_size(struct inode *inode, u64 new_size)
834 {
835 	struct super_block *sb = inode->i_sb;
836 	struct ntfs_sb_info *sbi = sb->s_fs_info;
837 	struct ntfs_inode *ni = ntfs_i(inode);
838 	int err;
839 
840 	/* Check for maximum file size. */
841 	if (is_sparsed(ni) || is_compressed(ni)) {
842 		if (new_size > sbi->maxbytes_sparse) {
843 			err = -EFBIG;
844 			goto out;
845 		}
846 	} else if (new_size > sbi->maxbytes) {
847 		err = -EFBIG;
848 		goto out;
849 	}
850 
851 	ni_lock(ni);
852 	down_write(&ni->file.run_lock);
853 
854 	err = attr_set_size(ni, ATTR_DATA, NULL, 0, &ni->file.run, new_size,
855 			    &ni->i_valid, true, NULL);
856 
857 	up_write(&ni->file.run_lock);
858 	ni_unlock(ni);
859 
860 	mark_inode_dirty(inode);
861 
862 out:
863 	return err;
864 }
865 
ntfs_resident_writepage(struct folio * folio,struct writeback_control * wbc,void * data)866 static int ntfs_resident_writepage(struct folio *folio,
867 				   struct writeback_control *wbc, void *data)
868 {
869 	struct address_space *mapping = data;
870 	struct inode *inode = mapping->host;
871 	struct ntfs_inode *ni = ntfs_i(inode);
872 	int ret;
873 
874 	if (unlikely(ntfs3_forced_shutdown(inode->i_sb)))
875 		return -EIO;
876 
877 	ni_lock(ni);
878 	ret = attr_data_write_resident(ni, folio);
879 	ni_unlock(ni);
880 
881 	if (ret != E_NTFS_NONRESIDENT)
882 		folio_unlock(folio);
883 	mapping_set_error(mapping, ret);
884 	return ret;
885 }
886 
ntfs_writepages(struct address_space * mapping,struct writeback_control * wbc)887 static int ntfs_writepages(struct address_space *mapping,
888 			   struct writeback_control *wbc)
889 {
890 	struct inode *inode = mapping->host;
891 
892 	if (unlikely(ntfs3_forced_shutdown(inode->i_sb)))
893 		return -EIO;
894 
895 	if (is_resident(ntfs_i(inode)))
896 		return write_cache_pages(mapping, wbc, ntfs_resident_writepage,
897 					 mapping);
898 	return mpage_writepages(mapping, wbc, ntfs_get_block);
899 }
900 
ntfs_get_block_write_begin(struct inode * inode,sector_t vbn,struct buffer_head * bh_result,int create)901 static int ntfs_get_block_write_begin(struct inode *inode, sector_t vbn,
902 				      struct buffer_head *bh_result, int create)
903 {
904 	return ntfs_get_block_vbo(inode, (u64)vbn << inode->i_blkbits,
905 				  bh_result, create, GET_BLOCK_WRITE_BEGIN);
906 }
907 
ntfs_write_begin(struct file * file,struct address_space * mapping,loff_t pos,u32 len,struct folio ** foliop,void ** fsdata)908 int ntfs_write_begin(struct file *file, struct address_space *mapping,
909 		     loff_t pos, u32 len, struct folio **foliop, void **fsdata)
910 {
911 	int err;
912 	struct inode *inode = mapping->host;
913 	struct ntfs_inode *ni = ntfs_i(inode);
914 
915 	if (unlikely(ntfs3_forced_shutdown(inode->i_sb)))
916 		return -EIO;
917 
918 	if (is_resident(ni)) {
919 		struct folio *folio = __filemap_get_folio(
920 			mapping, pos >> PAGE_SHIFT, FGP_WRITEBEGIN,
921 			mapping_gfp_mask(mapping));
922 
923 		if (IS_ERR(folio)) {
924 			err = PTR_ERR(folio);
925 			goto out;
926 		}
927 
928 		ni_lock(ni);
929 		err = attr_data_read_resident(ni, folio);
930 		ni_unlock(ni);
931 
932 		if (!err) {
933 			*foliop = folio;
934 			goto out;
935 		}
936 		folio_unlock(folio);
937 		folio_put(folio);
938 
939 		if (err != E_NTFS_NONRESIDENT)
940 			goto out;
941 	}
942 
943 	err = block_write_begin(mapping, pos, len, foliop,
944 				ntfs_get_block_write_begin);
945 
946 out:
947 	return err;
948 }
949 
950 /*
951  * ntfs_write_end - Address_space_operations::write_end.
952  */
ntfs_write_end(struct file * file,struct address_space * mapping,loff_t pos,u32 len,u32 copied,struct folio * folio,void * fsdata)953 int ntfs_write_end(struct file *file, struct address_space *mapping, loff_t pos,
954 		   u32 len, u32 copied, struct folio *folio, void *fsdata)
955 {
956 	struct inode *inode = mapping->host;
957 	struct ntfs_inode *ni = ntfs_i(inode);
958 	u64 valid = ni->i_valid;
959 	bool dirty = false;
960 	int err;
961 
962 	if (is_resident(ni)) {
963 		ni_lock(ni);
964 		err = attr_data_write_resident(ni, folio);
965 		ni_unlock(ni);
966 		if (!err) {
967 			struct buffer_head *head = folio_buffers(folio);
968 			dirty = true;
969 			/* Clear any buffers in folio. */
970 			if (head) {
971 				struct buffer_head *bh = head;
972 
973 				do {
974 					clear_buffer_dirty(bh);
975 					clear_buffer_mapped(bh);
976 					set_buffer_uptodate(bh);
977 				} while (head != (bh = bh->b_this_page));
978 			}
979 			folio_mark_uptodate(folio);
980 			err = copied;
981 		}
982 		folio_unlock(folio);
983 		folio_put(folio);
984 	} else {
985 		err = generic_write_end(file, mapping, pos, len, copied, folio,
986 					fsdata);
987 	}
988 
989 	if (err >= 0) {
990 		if (!(ni->std_fa & FILE_ATTRIBUTE_ARCHIVE)) {
991 			inode_set_mtime_to_ts(inode,
992 					      inode_set_ctime_current(inode));
993 			ni->std_fa |= FILE_ATTRIBUTE_ARCHIVE;
994 			dirty = true;
995 		}
996 
997 		if (valid != ni->i_valid) {
998 			/* ni->i_valid is changed in ntfs_get_block_vbo. */
999 			dirty = true;
1000 		}
1001 
1002 		if (pos + err > inode->i_size) {
1003 			i_size_write(inode, pos + err);
1004 			dirty = true;
1005 		}
1006 
1007 		if (dirty)
1008 			mark_inode_dirty(inode);
1009 	}
1010 
1011 	return err;
1012 }
1013 
ntfs3_write_inode(struct inode * inode,struct writeback_control * wbc)1014 int ntfs3_write_inode(struct inode *inode, struct writeback_control *wbc)
1015 {
1016 	return _ni_write_inode(inode, wbc->sync_mode == WB_SYNC_ALL);
1017 }
1018 
ntfs_sync_inode(struct inode * inode)1019 int ntfs_sync_inode(struct inode *inode)
1020 {
1021 	return _ni_write_inode(inode, 1);
1022 }
1023 
1024 /*
1025  * writeback_inode - Helper function for ntfs_flush_inodes().
1026  *
1027  * This writes both the inode and the file data blocks, waiting
1028  * for in flight data blocks before the start of the call.  It
1029  * does not wait for any io started during the call.
1030  */
writeback_inode(struct inode * inode)1031 static int writeback_inode(struct inode *inode)
1032 {
1033 	int ret = sync_inode_metadata(inode, 0);
1034 
1035 	if (!ret)
1036 		ret = filemap_fdatawrite(inode->i_mapping);
1037 	return ret;
1038 }
1039 
1040 /*
1041  * ntfs_flush_inodes
1042  *
1043  * Write data and metadata corresponding to i1 and i2.  The io is
1044  * started but we do not wait for any of it to finish.
1045  *
1046  * filemap_flush() is used for the block device, so if there is a dirty
1047  * page for a block already in flight, we will not wait and start the
1048  * io over again.
1049  */
ntfs_flush_inodes(struct super_block * sb,struct inode * i1,struct inode * i2)1050 int ntfs_flush_inodes(struct super_block *sb, struct inode *i1,
1051 		      struct inode *i2)
1052 {
1053 	int ret = 0;
1054 
1055 	if (i1)
1056 		ret = writeback_inode(i1);
1057 	if (!ret && i2)
1058 		ret = writeback_inode(i2);
1059 	if (!ret)
1060 		ret = filemap_flush(sb->s_bdev_file->f_mapping);
1061 	return ret;
1062 }
1063 
1064 /*
1065  * Helper function to read file.
1066  */
inode_read_data(struct inode * inode,void * data,size_t bytes)1067 int inode_read_data(struct inode *inode, void *data, size_t bytes)
1068 {
1069 	pgoff_t idx;
1070 	struct address_space *mapping = inode->i_mapping;
1071 
1072 	for (idx = 0; bytes; idx++) {
1073 		size_t op = bytes > PAGE_SIZE ? PAGE_SIZE : bytes;
1074 		struct page *page = read_mapping_page(mapping, idx, NULL);
1075 		void *kaddr;
1076 
1077 		if (IS_ERR(page))
1078 			return PTR_ERR(page);
1079 
1080 		kaddr = kmap_atomic(page);
1081 		memcpy(data, kaddr, op);
1082 		kunmap_atomic(kaddr);
1083 
1084 		put_page(page);
1085 
1086 		bytes -= op;
1087 		data = Add2Ptr(data, PAGE_SIZE);
1088 	}
1089 	return 0;
1090 }
1091 
1092 /*
1093  * ntfs_reparse_bytes
1094  *
1095  * Number of bytes for REPARSE_DATA_BUFFER(IO_REPARSE_TAG_SYMLINK)
1096  * for unicode string of @uni_len length.
1097  */
ntfs_reparse_bytes(u32 uni_len)1098 static inline u32 ntfs_reparse_bytes(u32 uni_len)
1099 {
1100 	/* Header + unicode string + decorated unicode string. */
1101 	return sizeof(short) * (2 * uni_len + 4) +
1102 	       offsetof(struct REPARSE_DATA_BUFFER,
1103 			SymbolicLinkReparseBuffer.PathBuffer);
1104 }
1105 
1106 static struct REPARSE_DATA_BUFFER *
ntfs_create_reparse_buffer(struct ntfs_sb_info * sbi,const char * symname,u32 size,u16 * nsize)1107 ntfs_create_reparse_buffer(struct ntfs_sb_info *sbi, const char *symname,
1108 			   u32 size, u16 *nsize)
1109 {
1110 	int i, err;
1111 	struct REPARSE_DATA_BUFFER *rp;
1112 	__le16 *rp_name;
1113 	typeof(rp->SymbolicLinkReparseBuffer) *rs;
1114 
1115 	rp = kzalloc(ntfs_reparse_bytes(2 * size + 2), GFP_NOFS);
1116 	if (!rp)
1117 		return ERR_PTR(-ENOMEM);
1118 
1119 	rs = &rp->SymbolicLinkReparseBuffer;
1120 	rp_name = rs->PathBuffer;
1121 
1122 	/* Convert link name to UTF-16. */
1123 	err = ntfs_nls_to_utf16(sbi, symname, size,
1124 				(struct cpu_str *)(rp_name - 1), 2 * size,
1125 				UTF16_LITTLE_ENDIAN);
1126 	if (err < 0)
1127 		goto out;
1128 
1129 	/* err = the length of unicode name of symlink. */
1130 	*nsize = ntfs_reparse_bytes(err);
1131 
1132 	if (*nsize > sbi->reparse.max_size) {
1133 		err = -EFBIG;
1134 		goto out;
1135 	}
1136 
1137 	/* Translate Linux '/' into Windows '\'. */
1138 	for (i = 0; i < err; i++) {
1139 		if (rp_name[i] == cpu_to_le16('/'))
1140 			rp_name[i] = cpu_to_le16('\\');
1141 	}
1142 
1143 	rp->ReparseTag = IO_REPARSE_TAG_SYMLINK;
1144 	rp->ReparseDataLength =
1145 		cpu_to_le16(*nsize - offsetof(struct REPARSE_DATA_BUFFER,
1146 					      SymbolicLinkReparseBuffer));
1147 
1148 	/* PrintName + SubstituteName. */
1149 	rs->SubstituteNameOffset = cpu_to_le16(sizeof(short) * err);
1150 	rs->SubstituteNameLength = cpu_to_le16(sizeof(short) * err + 8);
1151 	rs->PrintNameLength = rs->SubstituteNameOffset;
1152 
1153 	/*
1154 	 * TODO: Use relative path if possible to allow Windows to
1155 	 * parse this path.
1156 	 * 0-absolute path 1- relative path (SYMLINK_FLAG_RELATIVE).
1157 	 */
1158 	rs->Flags = 0;
1159 
1160 	memmove(rp_name + err + 4, rp_name, sizeof(short) * err);
1161 
1162 	/* Decorate SubstituteName. */
1163 	rp_name += err;
1164 	rp_name[0] = cpu_to_le16('\\');
1165 	rp_name[1] = cpu_to_le16('?');
1166 	rp_name[2] = cpu_to_le16('?');
1167 	rp_name[3] = cpu_to_le16('\\');
1168 
1169 	return rp;
1170 out:
1171 	kfree(rp);
1172 	return ERR_PTR(err);
1173 }
1174 
1175 /*
1176  * ntfs_create_inode
1177  *
1178  * Helper function for:
1179  * - ntfs_create
1180  * - ntfs_mknod
1181  * - ntfs_symlink
1182  * - ntfs_mkdir
1183  * - ntfs_atomic_open
1184  *
1185  * NOTE: if fnd != NULL (ntfs_atomic_open) then @dir is locked
1186  */
ntfs_create_inode(struct mnt_idmap * idmap,struct inode * dir,struct dentry * dentry,const struct cpu_str * uni,umode_t mode,dev_t dev,const char * symname,u32 size,struct ntfs_fnd * fnd)1187 int ntfs_create_inode(struct mnt_idmap *idmap, struct inode *dir,
1188 		      struct dentry *dentry, const struct cpu_str *uni,
1189 		      umode_t mode, dev_t dev, const char *symname, u32 size,
1190 		      struct ntfs_fnd *fnd)
1191 {
1192 	int err;
1193 	struct super_block *sb = dir->i_sb;
1194 	struct ntfs_sb_info *sbi = sb->s_fs_info;
1195 	const struct qstr *name = &dentry->d_name;
1196 	CLST ino = 0;
1197 	struct ntfs_inode *dir_ni = ntfs_i(dir);
1198 	struct ntfs_inode *ni = NULL;
1199 	struct inode *inode = NULL;
1200 	struct ATTRIB *attr;
1201 	struct ATTR_STD_INFO5 *std5;
1202 	struct ATTR_FILE_NAME *fname;
1203 	struct MFT_REC *rec;
1204 	u32 asize, dsize, sd_size;
1205 	enum FILE_ATTRIBUTE fa;
1206 	__le32 security_id = SECURITY_ID_INVALID;
1207 	CLST vcn;
1208 	const void *sd;
1209 	u16 t16, nsize = 0, aid = 0;
1210 	struct INDEX_ROOT *root, *dir_root;
1211 	struct NTFS_DE *e, *new_de = NULL;
1212 	struct REPARSE_DATA_BUFFER *rp = NULL;
1213 	bool rp_inserted = false;
1214 
1215 	/* New file will be resident or non resident. */
1216 	const bool new_file_resident = 1;
1217 
1218 	if (!fnd)
1219 		ni_lock_dir(dir_ni);
1220 
1221 	dir_root = indx_get_root(&dir_ni->dir, dir_ni, NULL, NULL);
1222 	if (!dir_root) {
1223 		err = -EINVAL;
1224 		goto out1;
1225 	}
1226 
1227 	if (S_ISDIR(mode)) {
1228 		/* Use parent's directory attributes. */
1229 		fa = dir_ni->std_fa | FILE_ATTRIBUTE_DIRECTORY |
1230 		     FILE_ATTRIBUTE_ARCHIVE;
1231 		/*
1232 		 * By default child directory inherits parent attributes.
1233 		 * Root directory is hidden + system.
1234 		 * Make an exception for children in root.
1235 		 */
1236 		if (dir->i_ino == MFT_REC_ROOT)
1237 			fa &= ~(FILE_ATTRIBUTE_HIDDEN | FILE_ATTRIBUTE_SYSTEM);
1238 	} else if (S_ISLNK(mode)) {
1239 		/* It is good idea that link should be the same type (file/dir) as target */
1240 		fa = FILE_ATTRIBUTE_REPARSE_POINT;
1241 
1242 		/*
1243 		 * Linux: there are dir/file/symlink and so on.
1244 		 * NTFS: symlinks are "dir + reparse" or "file + reparse"
1245 		 * It is good idea to create:
1246 		 * dir + reparse if 'symname' points to directory
1247 		 * or
1248 		 * file + reparse if 'symname' points to file
1249 		 * Unfortunately kern_path hangs if symname contains 'dir'.
1250 		 */
1251 
1252 		/*
1253 		 *	struct path path;
1254 		 *
1255 		 *	if (!kern_path(symname, LOOKUP_FOLLOW, &path)){
1256 		 *		struct inode *target = d_inode(path.dentry);
1257 		 *
1258 		 *		if (S_ISDIR(target->i_mode))
1259 		 *			fa |= FILE_ATTRIBUTE_DIRECTORY;
1260 		 *		// if ( target->i_sb == sb ){
1261 		 *		//	use relative path?
1262 		 *		// }
1263 		 *		path_put(&path);
1264 		 *	}
1265 		 */
1266 	} else if (S_ISREG(mode)) {
1267 		if (sbi->options->sparse) {
1268 			/* Sparsed regular file, cause option 'sparse'. */
1269 			fa = FILE_ATTRIBUTE_SPARSE_FILE |
1270 			     FILE_ATTRIBUTE_ARCHIVE;
1271 		} else if (dir_ni->std_fa & FILE_ATTRIBUTE_COMPRESSED) {
1272 			/* Compressed regular file, if parent is compressed. */
1273 			fa = FILE_ATTRIBUTE_COMPRESSED | FILE_ATTRIBUTE_ARCHIVE;
1274 		} else {
1275 			/* Regular file, default attributes. */
1276 			fa = FILE_ATTRIBUTE_ARCHIVE;
1277 		}
1278 	} else {
1279 		fa = FILE_ATTRIBUTE_ARCHIVE;
1280 	}
1281 
1282 	/* If option "hide_dot_files" then set hidden attribute for dot files. */
1283 	if (sbi->options->hide_dot_files && name->name[0] == '.')
1284 		fa |= FILE_ATTRIBUTE_HIDDEN;
1285 
1286 	if (!(mode & 0222))
1287 		fa |= FILE_ATTRIBUTE_READONLY;
1288 
1289 	/* Allocate PATH_MAX bytes. */
1290 	new_de = __getname();
1291 	if (!new_de) {
1292 		err = -ENOMEM;
1293 		goto out1;
1294 	}
1295 
1296 	if (unlikely(ntfs3_forced_shutdown(sb))) {
1297 		err = -EIO;
1298 		goto out2;
1299 	}
1300 
1301 	/* Mark rw ntfs as dirty. it will be cleared at umount. */
1302 	ntfs_set_state(sbi, NTFS_DIRTY_DIRTY);
1303 
1304 	/* Step 1: allocate and fill new mft record. */
1305 	err = ntfs_look_free_mft(sbi, &ino, false, NULL, NULL);
1306 	if (err)
1307 		goto out2;
1308 
1309 	ni = ntfs_new_inode(sbi, ino, S_ISDIR(mode) ? RECORD_FLAG_DIR : 0);
1310 	if (IS_ERR(ni)) {
1311 		err = PTR_ERR(ni);
1312 		ni = NULL;
1313 		goto out3;
1314 	}
1315 	inode = &ni->vfs_inode;
1316 	inode_init_owner(idmap, inode, dir, mode);
1317 	mode = inode->i_mode;
1318 
1319 	ni->i_crtime = current_time(inode);
1320 
1321 	rec = ni->mi.mrec;
1322 	rec->hard_links = cpu_to_le16(1);
1323 	attr = Add2Ptr(rec, le16_to_cpu(rec->attr_off));
1324 
1325 	/* Get default security id. */
1326 	sd = s_default_security;
1327 	sd_size = sizeof(s_default_security);
1328 
1329 	if (is_ntfs3(sbi)) {
1330 		security_id = dir_ni->std_security_id;
1331 		if (le32_to_cpu(security_id) < SECURITY_ID_FIRST) {
1332 			security_id = sbi->security.def_security_id;
1333 
1334 			if (security_id == SECURITY_ID_INVALID &&
1335 			    !ntfs_insert_security(sbi, sd, sd_size,
1336 						  &security_id, NULL))
1337 				sbi->security.def_security_id = security_id;
1338 		}
1339 	}
1340 
1341 	/* Insert standard info. */
1342 	std5 = Add2Ptr(attr, SIZEOF_RESIDENT);
1343 
1344 	if (security_id == SECURITY_ID_INVALID) {
1345 		dsize = sizeof(struct ATTR_STD_INFO);
1346 	} else {
1347 		dsize = sizeof(struct ATTR_STD_INFO5);
1348 		std5->security_id = security_id;
1349 		ni->std_security_id = security_id;
1350 	}
1351 	asize = SIZEOF_RESIDENT + dsize;
1352 
1353 	attr->type = ATTR_STD;
1354 	attr->size = cpu_to_le32(asize);
1355 	attr->id = cpu_to_le16(aid++);
1356 	attr->res.data_off = SIZEOF_RESIDENT_LE;
1357 	attr->res.data_size = cpu_to_le32(dsize);
1358 
1359 	std5->cr_time = std5->m_time = std5->c_time = std5->a_time =
1360 		kernel2nt(&ni->i_crtime);
1361 
1362 	std5->fa = ni->std_fa = fa;
1363 
1364 	attr = Add2Ptr(attr, asize);
1365 
1366 	/* Insert file name. */
1367 	err = fill_name_de(sbi, new_de, name, uni);
1368 	if (err)
1369 		goto out4;
1370 
1371 	mi_get_ref(&ni->mi, &new_de->ref);
1372 
1373 	fname = (struct ATTR_FILE_NAME *)(new_de + 1);
1374 
1375 	if (sbi->options->windows_names &&
1376 	    !valid_windows_name(sbi, (struct le_str *)&fname->name_len)) {
1377 		err = -EINVAL;
1378 		goto out4;
1379 	}
1380 
1381 	mi_get_ref(&dir_ni->mi, &fname->home);
1382 	fname->dup.cr_time = fname->dup.m_time = fname->dup.c_time =
1383 		fname->dup.a_time = std5->cr_time;
1384 	fname->dup.alloc_size = fname->dup.data_size = 0;
1385 	fname->dup.fa = std5->fa;
1386 	fname->dup.ea_size = fname->dup.reparse = 0;
1387 
1388 	dsize = le16_to_cpu(new_de->key_size);
1389 	asize = ALIGN(SIZEOF_RESIDENT + dsize, 8);
1390 
1391 	attr->type = ATTR_NAME;
1392 	attr->size = cpu_to_le32(asize);
1393 	attr->res.data_off = SIZEOF_RESIDENT_LE;
1394 	attr->res.flags = RESIDENT_FLAG_INDEXED;
1395 	attr->id = cpu_to_le16(aid++);
1396 	attr->res.data_size = cpu_to_le32(dsize);
1397 	memcpy(Add2Ptr(attr, SIZEOF_RESIDENT), fname, dsize);
1398 
1399 	attr = Add2Ptr(attr, asize);
1400 
1401 	if (security_id == SECURITY_ID_INVALID) {
1402 		/* Insert security attribute. */
1403 		asize = SIZEOF_RESIDENT + ALIGN(sd_size, 8);
1404 
1405 		attr->type = ATTR_SECURE;
1406 		attr->size = cpu_to_le32(asize);
1407 		attr->id = cpu_to_le16(aid++);
1408 		attr->res.data_off = SIZEOF_RESIDENT_LE;
1409 		attr->res.data_size = cpu_to_le32(sd_size);
1410 		memcpy(Add2Ptr(attr, SIZEOF_RESIDENT), sd, sd_size);
1411 
1412 		attr = Add2Ptr(attr, asize);
1413 	}
1414 
1415 	attr->id = cpu_to_le16(aid++);
1416 	if (fa & FILE_ATTRIBUTE_DIRECTORY) {
1417 		/*
1418 		 * Regular directory or symlink to directory.
1419 		 * Create root attribute.
1420 		 */
1421 		dsize = sizeof(struct INDEX_ROOT) + sizeof(struct NTFS_DE);
1422 		asize = sizeof(I30_NAME) + SIZEOF_RESIDENT + dsize;
1423 
1424 		attr->type = ATTR_ROOT;
1425 		attr->size = cpu_to_le32(asize);
1426 
1427 		attr->name_len = ARRAY_SIZE(I30_NAME);
1428 		attr->name_off = SIZEOF_RESIDENT_LE;
1429 		attr->res.data_off =
1430 			cpu_to_le16(sizeof(I30_NAME) + SIZEOF_RESIDENT);
1431 		attr->res.data_size = cpu_to_le32(dsize);
1432 		memcpy(Add2Ptr(attr, SIZEOF_RESIDENT), I30_NAME,
1433 		       sizeof(I30_NAME));
1434 
1435 		root = Add2Ptr(attr, sizeof(I30_NAME) + SIZEOF_RESIDENT);
1436 		memcpy(root, dir_root, offsetof(struct INDEX_ROOT, ihdr));
1437 		root->ihdr.de_off = cpu_to_le32(sizeof(struct INDEX_HDR));
1438 		root->ihdr.used = cpu_to_le32(sizeof(struct INDEX_HDR) +
1439 					      sizeof(struct NTFS_DE));
1440 		root->ihdr.total = root->ihdr.used;
1441 
1442 		e = Add2Ptr(root, sizeof(struct INDEX_ROOT));
1443 		e->size = cpu_to_le16(sizeof(struct NTFS_DE));
1444 		e->flags = NTFS_IE_LAST;
1445 	} else if (S_ISLNK(mode)) {
1446 		/*
1447 		 * Symlink to file.
1448 		 * Create empty resident data attribute.
1449 		 */
1450 		asize = SIZEOF_RESIDENT;
1451 
1452 		/* Insert empty ATTR_DATA */
1453 		attr->type = ATTR_DATA;
1454 		attr->size = cpu_to_le32(SIZEOF_RESIDENT);
1455 		attr->name_off = SIZEOF_RESIDENT_LE;
1456 		attr->res.data_off = SIZEOF_RESIDENT_LE;
1457 	} else if (!new_file_resident && S_ISREG(mode)) {
1458 		/*
1459 		 * Regular file. Create empty non resident data attribute.
1460 		 */
1461 		attr->type = ATTR_DATA;
1462 		attr->non_res = 1;
1463 		attr->nres.evcn = cpu_to_le64(-1ll);
1464 		if (fa & FILE_ATTRIBUTE_SPARSE_FILE) {
1465 			attr->size = cpu_to_le32(SIZEOF_NONRESIDENT_EX + 8);
1466 			attr->name_off = SIZEOF_NONRESIDENT_EX_LE;
1467 			attr->flags = ATTR_FLAG_SPARSED;
1468 			asize = SIZEOF_NONRESIDENT_EX + 8;
1469 		} else if (fa & FILE_ATTRIBUTE_COMPRESSED) {
1470 			attr->size = cpu_to_le32(SIZEOF_NONRESIDENT_EX + 8);
1471 			attr->name_off = SIZEOF_NONRESIDENT_EX_LE;
1472 			attr->flags = ATTR_FLAG_COMPRESSED;
1473 			attr->nres.c_unit = NTFS_LZNT_CUNIT;
1474 			asize = SIZEOF_NONRESIDENT_EX + 8;
1475 		} else {
1476 			attr->size = cpu_to_le32(SIZEOF_NONRESIDENT + 8);
1477 			attr->name_off = SIZEOF_NONRESIDENT_LE;
1478 			asize = SIZEOF_NONRESIDENT + 8;
1479 		}
1480 		attr->nres.run_off = attr->name_off;
1481 	} else {
1482 		/*
1483 		 * Node. Create empty resident data attribute.
1484 		 */
1485 		attr->type = ATTR_DATA;
1486 		attr->size = cpu_to_le32(SIZEOF_RESIDENT);
1487 		attr->name_off = SIZEOF_RESIDENT_LE;
1488 		if (fa & FILE_ATTRIBUTE_SPARSE_FILE)
1489 			attr->flags = ATTR_FLAG_SPARSED;
1490 		else if (fa & FILE_ATTRIBUTE_COMPRESSED)
1491 			attr->flags = ATTR_FLAG_COMPRESSED;
1492 		attr->res.data_off = SIZEOF_RESIDENT_LE;
1493 		asize = SIZEOF_RESIDENT;
1494 		ni->ni_flags |= NI_FLAG_RESIDENT;
1495 	}
1496 
1497 	if (S_ISDIR(mode)) {
1498 		ni->ni_flags |= NI_FLAG_DIR;
1499 		err = indx_init(&ni->dir, sbi, attr, INDEX_MUTEX_I30);
1500 		if (err)
1501 			goto out4;
1502 	} else if (S_ISLNK(mode)) {
1503 		rp = ntfs_create_reparse_buffer(sbi, symname, size, &nsize);
1504 
1505 		if (IS_ERR(rp)) {
1506 			err = PTR_ERR(rp);
1507 			rp = NULL;
1508 			goto out4;
1509 		}
1510 
1511 		/*
1512 		 * Insert ATTR_REPARSE.
1513 		 */
1514 		attr = Add2Ptr(attr, asize);
1515 		attr->type = ATTR_REPARSE;
1516 		attr->id = cpu_to_le16(aid++);
1517 
1518 		/* Resident or non resident? */
1519 		asize = ALIGN(SIZEOF_RESIDENT + nsize, 8);
1520 		t16 = PtrOffset(rec, attr);
1521 
1522 		/*
1523 		 * Below function 'ntfs_save_wsl_perm' requires 0x78 bytes.
1524 		 * It is good idea to keep extended attributes resident.
1525 		 */
1526 		if (asize + t16 + 0x78 + 8 > sbi->record_size) {
1527 			CLST alen;
1528 			CLST clst = bytes_to_cluster(sbi, nsize);
1529 
1530 			/* Bytes per runs. */
1531 			t16 = sbi->record_size - t16 - SIZEOF_NONRESIDENT;
1532 
1533 			attr->non_res = 1;
1534 			attr->nres.evcn = cpu_to_le64(clst - 1);
1535 			attr->name_off = SIZEOF_NONRESIDENT_LE;
1536 			attr->nres.run_off = attr->name_off;
1537 			attr->nres.data_size = cpu_to_le64(nsize);
1538 			attr->nres.valid_size = attr->nres.data_size;
1539 			attr->nres.alloc_size =
1540 				cpu_to_le64(ntfs_up_cluster(sbi, nsize));
1541 
1542 			err = attr_allocate_clusters(sbi, &ni->file.run, 0, 0,
1543 						     clst, NULL, ALLOCATE_DEF,
1544 						     &alen, 0, NULL, NULL);
1545 			if (err)
1546 				goto out5;
1547 
1548 			err = run_pack(&ni->file.run, 0, clst,
1549 				       Add2Ptr(attr, SIZEOF_NONRESIDENT), t16,
1550 				       &vcn);
1551 			if (err < 0)
1552 				goto out5;
1553 
1554 			if (vcn != clst) {
1555 				err = -EINVAL;
1556 				goto out5;
1557 			}
1558 
1559 			asize = SIZEOF_NONRESIDENT + ALIGN(err, 8);
1560 			/* Write non resident data. */
1561 			err = ntfs_sb_write_run(sbi, &ni->file.run, 0, rp,
1562 						nsize, 0);
1563 			if (err)
1564 				goto out5;
1565 		} else {
1566 			attr->res.data_off = SIZEOF_RESIDENT_LE;
1567 			attr->res.data_size = cpu_to_le32(nsize);
1568 			memcpy(Add2Ptr(attr, SIZEOF_RESIDENT), rp, nsize);
1569 		}
1570 		/* Size of symlink equals the length of input string. */
1571 		inode->i_size = size;
1572 
1573 		attr->size = cpu_to_le32(asize);
1574 
1575 		err = ntfs_insert_reparse(sbi, IO_REPARSE_TAG_SYMLINK,
1576 					  &new_de->ref);
1577 		if (err)
1578 			goto out5;
1579 
1580 		rp_inserted = true;
1581 	}
1582 
1583 	attr = Add2Ptr(attr, asize);
1584 	attr->type = ATTR_END;
1585 
1586 	rec->used = cpu_to_le32(PtrOffset(rec, attr) + 8);
1587 	rec->next_attr_id = cpu_to_le16(aid);
1588 
1589 	inode->i_generation = le16_to_cpu(rec->seq);
1590 
1591 	if (S_ISDIR(mode)) {
1592 		inode->i_op = &ntfs_dir_inode_operations;
1593 		inode->i_fop = unlikely(is_legacy_ntfs(sb)) ?
1594 				       &ntfs_legacy_dir_operations :
1595 				       &ntfs_dir_operations;
1596 	} else if (S_ISLNK(mode)) {
1597 		inode->i_op = &ntfs_link_inode_operations;
1598 		inode->i_fop = NULL;
1599 		inode->i_mapping->a_ops = &ntfs_aops;
1600 		inode->i_size = size;
1601 		inode_nohighmem(inode);
1602 	} else if (S_ISREG(mode)) {
1603 		inode->i_op = &ntfs_file_inode_operations;
1604 		inode->i_fop = unlikely(is_legacy_ntfs(sb)) ?
1605 				       &ntfs_legacy_file_operations :
1606 				       &ntfs_file_operations;
1607 		inode->i_mapping->a_ops = is_compressed(ni) ? &ntfs_aops_cmpr :
1608 							      &ntfs_aops;
1609 		init_rwsem(&ni->file.run_lock);
1610 	} else {
1611 		inode->i_op = &ntfs_special_inode_operations;
1612 		init_special_inode(inode, mode, dev);
1613 	}
1614 
1615 #ifdef CONFIG_NTFS3_FS_POSIX_ACL
1616 	if (!S_ISLNK(mode) && (sb->s_flags & SB_POSIXACL)) {
1617 		err = ntfs_init_acl(idmap, inode, dir);
1618 		if (err)
1619 			goto out5;
1620 	} else
1621 #endif
1622 	{
1623 		inode->i_flags |= S_NOSEC;
1624 	}
1625 
1626 	/*
1627 	 * ntfs_init_acl and ntfs_save_wsl_perm update extended attribute.
1628 	 * The packed size of extended attribute is stored in direntry too.
1629 	 * 'fname' here points to inside new_de.
1630 	 */
1631 	err = ntfs_save_wsl_perm(inode, &fname->dup.ea_size);
1632 	if (err)
1633 		goto out6;
1634 
1635 	/*
1636 	 * update ea_size in file_name attribute too.
1637 	 * Use ni_find_attr cause layout of MFT record may be changed
1638 	 * in ntfs_init_acl and ntfs_save_wsl_perm.
1639 	 */
1640 	attr = ni_find_attr(ni, NULL, NULL, ATTR_NAME, NULL, 0, NULL, NULL);
1641 	if (attr) {
1642 		struct ATTR_FILE_NAME *fn;
1643 
1644 		fn = resident_data_ex(attr, SIZEOF_ATTRIBUTE_FILENAME);
1645 		if (fn)
1646 			fn->dup.ea_size = fname->dup.ea_size;
1647 	}
1648 
1649 	/* We do not need to update parent directory later */
1650 	ni->ni_flags &= ~NI_FLAG_UPDATE_PARENT;
1651 
1652 	/* Step 2: Add new name in index. */
1653 	err = indx_insert_entry(&dir_ni->dir, dir_ni, new_de, sbi, fnd, 0);
1654 	if (err)
1655 		goto out6;
1656 
1657 	/*
1658 	 * Call 'd_instantiate' after inode->i_op is set
1659 	 * but before finish_open.
1660 	 */
1661 	d_instantiate(dentry, inode);
1662 
1663 	/* Set original time. inode times (i_ctime) may be changed in ntfs_init_acl. */
1664 	inode_set_atime_to_ts(inode, ni->i_crtime);
1665 	inode_set_ctime_to_ts(inode, ni->i_crtime);
1666 	inode_set_mtime_to_ts(inode, ni->i_crtime);
1667 	inode_set_mtime_to_ts(dir, ni->i_crtime);
1668 	inode_set_ctime_to_ts(dir, ni->i_crtime);
1669 
1670 	mark_inode_dirty(dir);
1671 	mark_inode_dirty(inode);
1672 
1673 	/* Normal exit. */
1674 	goto out2;
1675 
1676 out6:
1677 	attr = ni_find_attr(ni, NULL, NULL, ATTR_EA, NULL, 0, NULL, NULL);
1678 	if (attr && attr->non_res) {
1679 		/* Delete ATTR_EA, if non-resident. */
1680 		struct runs_tree run;
1681 		run_init(&run);
1682 		attr_set_size(ni, ATTR_EA, NULL, 0, &run, 0, NULL, false, NULL);
1683 		run_close(&run);
1684 	}
1685 
1686 	if (rp_inserted)
1687 		ntfs_remove_reparse(sbi, IO_REPARSE_TAG_SYMLINK, &new_de->ref);
1688 
1689 out5:
1690 	if (!S_ISDIR(mode))
1691 		run_deallocate(sbi, &ni->file.run, false);
1692 
1693 out4:
1694 	clear_rec_inuse(rec);
1695 	clear_nlink(inode);
1696 	ni->mi.dirty = false;
1697 	discard_new_inode(inode);
1698 out3:
1699 	ntfs_mark_rec_free(sbi, ino, false);
1700 
1701 out2:
1702 	__putname(new_de);
1703 	kfree(rp);
1704 
1705 out1:
1706 	if (!fnd)
1707 		ni_unlock(dir_ni);
1708 
1709 	if (!err)
1710 		unlock_new_inode(inode);
1711 
1712 	return err;
1713 }
1714 
ntfs_link_inode(struct inode * inode,struct dentry * dentry)1715 int ntfs_link_inode(struct inode *inode, struct dentry *dentry)
1716 {
1717 	int err;
1718 	struct ntfs_inode *ni = ntfs_i(inode);
1719 	struct ntfs_sb_info *sbi = inode->i_sb->s_fs_info;
1720 	struct NTFS_DE *de;
1721 
1722 	/* Allocate PATH_MAX bytes. */
1723 	de = __getname();
1724 	if (!de)
1725 		return -ENOMEM;
1726 
1727 	/* Mark rw ntfs as dirty. It will be cleared at umount. */
1728 	ntfs_set_state(sbi, NTFS_DIRTY_DIRTY);
1729 
1730 	/* Construct 'de'. */
1731 	err = fill_name_de(sbi, de, &dentry->d_name, NULL);
1732 	if (err)
1733 		goto out;
1734 
1735 	err = ni_add_name(ntfs_i(d_inode(dentry->d_parent)), ni, de);
1736 out:
1737 	__putname(de);
1738 	return err;
1739 }
1740 
1741 /*
1742  * ntfs_unlink_inode
1743  *
1744  * inode_operations::unlink
1745  * inode_operations::rmdir
1746  */
ntfs_unlink_inode(struct inode * dir,const struct dentry * dentry)1747 int ntfs_unlink_inode(struct inode *dir, const struct dentry *dentry)
1748 {
1749 	int err;
1750 	struct ntfs_sb_info *sbi = dir->i_sb->s_fs_info;
1751 	struct inode *inode = d_inode(dentry);
1752 	struct ntfs_inode *ni = ntfs_i(inode);
1753 	struct ntfs_inode *dir_ni = ntfs_i(dir);
1754 	struct NTFS_DE *de, *de2 = NULL;
1755 	int undo_remove;
1756 
1757 	if (ntfs_is_meta_file(sbi, ni->mi.rno))
1758 		return -EINVAL;
1759 
1760 	/* Allocate PATH_MAX bytes. */
1761 	de = __getname();
1762 	if (!de)
1763 		return -ENOMEM;
1764 
1765 	ni_lock(ni);
1766 
1767 	if (S_ISDIR(inode->i_mode) && !dir_is_empty(inode)) {
1768 		err = -ENOTEMPTY;
1769 		goto out;
1770 	}
1771 
1772 	err = fill_name_de(sbi, de, &dentry->d_name, NULL);
1773 	if (err < 0)
1774 		goto out;
1775 
1776 	undo_remove = 0;
1777 	err = ni_remove_name(dir_ni, ni, de, &de2, &undo_remove);
1778 
1779 	if (!err) {
1780 		drop_nlink(inode);
1781 		inode_set_mtime_to_ts(dir, inode_set_ctime_current(dir));
1782 		mark_inode_dirty(dir);
1783 		inode_set_ctime_to_ts(inode, inode_get_ctime(dir));
1784 		if (inode->i_nlink)
1785 			mark_inode_dirty(inode);
1786 	} else if (!ni_remove_name_undo(dir_ni, ni, de, de2, undo_remove)) {
1787 		_ntfs_bad_inode(inode);
1788 	} else {
1789 		if (ni_is_dirty(dir))
1790 			mark_inode_dirty(dir);
1791 		if (ni_is_dirty(inode))
1792 			mark_inode_dirty(inode);
1793 	}
1794 
1795 out:
1796 	ni_unlock(ni);
1797 	__putname(de);
1798 	return err;
1799 }
1800 
ntfs_evict_inode(struct inode * inode)1801 void ntfs_evict_inode(struct inode *inode)
1802 {
1803 	truncate_inode_pages_final(&inode->i_data);
1804 
1805 	invalidate_inode_buffers(inode);
1806 	clear_inode(inode);
1807 
1808 	ni_clear(ntfs_i(inode));
1809 }
1810 
1811 /*
1812  * ntfs_translate_junction
1813  *
1814  * Translate a Windows junction target to the Linux equivalent.
1815  * On junctions, targets are always absolute (they include the drive
1816  * letter). We have no way of knowing if the target is for the current
1817  * mounted device or not so we just assume it is.
1818  */
ntfs_translate_junction(const struct super_block * sb,const struct dentry * link_de,char * target,int target_len,int target_max)1819 static int ntfs_translate_junction(const struct super_block *sb,
1820 				   const struct dentry *link_de, char *target,
1821 				   int target_len, int target_max)
1822 {
1823 	int tl_len, err = target_len;
1824 	char *link_path_buffer = NULL, *link_path;
1825 	char *translated = NULL;
1826 	char *target_start;
1827 	int copy_len;
1828 
1829 	link_path_buffer = kmalloc(PATH_MAX, GFP_NOFS);
1830 	if (!link_path_buffer) {
1831 		err = -ENOMEM;
1832 		goto out;
1833 	}
1834 	/* Get link path, relative to mount point */
1835 	link_path = dentry_path_raw(link_de, link_path_buffer, PATH_MAX);
1836 	if (IS_ERR(link_path)) {
1837 		ntfs_err(sb, "Error getting link path");
1838 		err = -EINVAL;
1839 		goto out;
1840 	}
1841 
1842 	translated = kmalloc(PATH_MAX, GFP_NOFS);
1843 	if (!translated) {
1844 		err = -ENOMEM;
1845 		goto out;
1846 	}
1847 
1848 	/* Make translated path a relative path to mount point */
1849 	strcpy(translated, "./");
1850 	++link_path; /* Skip leading / */
1851 	for (tl_len = sizeof("./") - 1; *link_path; ++link_path) {
1852 		if (*link_path == '/') {
1853 			if (PATH_MAX - tl_len < sizeof("../")) {
1854 				ntfs_err(sb,
1855 					 "Link path %s has too many components",
1856 					 link_path);
1857 				err = -EINVAL;
1858 				goto out;
1859 			}
1860 			strcpy(translated + tl_len, "../");
1861 			tl_len += sizeof("../") - 1;
1862 		}
1863 	}
1864 
1865 	/* Skip drive letter */
1866 	target_start = target;
1867 	while (*target_start && *target_start != ':')
1868 		++target_start;
1869 
1870 	if (!*target_start) {
1871 		ntfs_err(sb, "Link target (%s) missing drive separator",
1872 			 target);
1873 		err = -EINVAL;
1874 		goto out;
1875 	}
1876 
1877 	/* Skip drive separator and leading /, if exists */
1878 	target_start += 1 + (target_start[1] == '/');
1879 	copy_len = target_len - (target_start - target);
1880 
1881 	if (PATH_MAX - tl_len <= copy_len) {
1882 		ntfs_err(sb, "Link target %s too large for buffer (%d <= %d)",
1883 			 target_start, PATH_MAX - tl_len, copy_len);
1884 		err = -EINVAL;
1885 		goto out;
1886 	}
1887 
1888 	/* translated path has a trailing / and target_start does not */
1889 	strcpy(translated + tl_len, target_start);
1890 	tl_len += copy_len;
1891 	if (target_max <= tl_len) {
1892 		ntfs_err(sb, "Target path %s too large for buffer (%d <= %d)",
1893 			 translated, target_max, tl_len);
1894 		err = -EINVAL;
1895 		goto out;
1896 	}
1897 	strcpy(target, translated);
1898 	err = tl_len;
1899 
1900 out:
1901 	kfree(link_path_buffer);
1902 	kfree(translated);
1903 	return err;
1904 }
1905 
ntfs_readlink_hlp(const struct dentry * link_de,struct inode * inode,char * buffer,int buflen)1906 static noinline int ntfs_readlink_hlp(const struct dentry *link_de,
1907 				      struct inode *inode, char *buffer,
1908 				      int buflen)
1909 {
1910 	int i, err = -EINVAL;
1911 	struct ntfs_inode *ni = ntfs_i(inode);
1912 	struct super_block *sb = inode->i_sb;
1913 	struct ntfs_sb_info *sbi = sb->s_fs_info;
1914 	u64 size;
1915 	u16 ulen = 0;
1916 	void *to_free = NULL;
1917 	struct REPARSE_DATA_BUFFER *rp;
1918 	const __le16 *uname;
1919 	struct ATTRIB *attr;
1920 
1921 	/* Reparse data present. Try to parse it. */
1922 	static_assert(!offsetof(struct REPARSE_DATA_BUFFER, ReparseTag));
1923 	static_assert(sizeof(u32) == sizeof(rp->ReparseTag));
1924 
1925 	*buffer = 0;
1926 
1927 	attr = ni_find_attr(ni, NULL, NULL, ATTR_REPARSE, NULL, 0, NULL, NULL);
1928 	if (!attr)
1929 		goto out;
1930 
1931 	if (!attr->non_res) {
1932 		rp = resident_data_ex(attr, sizeof(struct REPARSE_DATA_BUFFER));
1933 		if (!rp)
1934 			goto out;
1935 		size = le32_to_cpu(attr->res.data_size);
1936 	} else {
1937 		size = le64_to_cpu(attr->nres.data_size);
1938 		rp = NULL;
1939 	}
1940 
1941 	if (size > sbi->reparse.max_size || size <= sizeof(u32))
1942 		goto out;
1943 
1944 	if (!rp) {
1945 		rp = kmalloc(size, GFP_NOFS);
1946 		if (!rp) {
1947 			err = -ENOMEM;
1948 			goto out;
1949 		}
1950 		to_free = rp;
1951 		/* Read into temporal buffer. */
1952 		err = ntfs_read_run_nb(sbi, &ni->file.run, 0, rp, size, NULL);
1953 		if (err)
1954 			goto out;
1955 	}
1956 
1957 	/* Microsoft Tag. */
1958 	switch (rp->ReparseTag) {
1959 	case IO_REPARSE_TAG_MOUNT_POINT:
1960 		/* Mount points and junctions. */
1961 		/* Can we use 'Rp->MountPointReparseBuffer.PrintNameLength'? */
1962 		if (size <= offsetof(struct REPARSE_DATA_BUFFER,
1963 				     MountPointReparseBuffer.PathBuffer))
1964 			goto out;
1965 		uname = Add2Ptr(rp,
1966 				offsetof(struct REPARSE_DATA_BUFFER,
1967 					 MountPointReparseBuffer.PathBuffer) +
1968 					le16_to_cpu(rp->MountPointReparseBuffer
1969 							    .PrintNameOffset));
1970 		ulen = le16_to_cpu(rp->MountPointReparseBuffer.PrintNameLength);
1971 		break;
1972 
1973 	case IO_REPARSE_TAG_SYMLINK:
1974 		/* FolderSymbolicLink */
1975 		/* Can we use 'Rp->SymbolicLinkReparseBuffer.PrintNameLength'? */
1976 		if (size <= offsetof(struct REPARSE_DATA_BUFFER,
1977 				     SymbolicLinkReparseBuffer.PathBuffer))
1978 			goto out;
1979 		uname = Add2Ptr(
1980 			rp, offsetof(struct REPARSE_DATA_BUFFER,
1981 				     SymbolicLinkReparseBuffer.PathBuffer) +
1982 				    le16_to_cpu(rp->SymbolicLinkReparseBuffer
1983 							.PrintNameOffset));
1984 		ulen = le16_to_cpu(
1985 			rp->SymbolicLinkReparseBuffer.PrintNameLength);
1986 		break;
1987 
1988 	case IO_REPARSE_TAG_CLOUD:
1989 	case IO_REPARSE_TAG_CLOUD_1:
1990 	case IO_REPARSE_TAG_CLOUD_2:
1991 	case IO_REPARSE_TAG_CLOUD_3:
1992 	case IO_REPARSE_TAG_CLOUD_4:
1993 	case IO_REPARSE_TAG_CLOUD_5:
1994 	case IO_REPARSE_TAG_CLOUD_6:
1995 	case IO_REPARSE_TAG_CLOUD_7:
1996 	case IO_REPARSE_TAG_CLOUD_8:
1997 	case IO_REPARSE_TAG_CLOUD_9:
1998 	case IO_REPARSE_TAG_CLOUD_A:
1999 	case IO_REPARSE_TAG_CLOUD_B:
2000 	case IO_REPARSE_TAG_CLOUD_C:
2001 	case IO_REPARSE_TAG_CLOUD_D:
2002 	case IO_REPARSE_TAG_CLOUD_E:
2003 	case IO_REPARSE_TAG_CLOUD_F:
2004 		err = sizeof("OneDrive") - 1;
2005 		if (err > buflen)
2006 			err = buflen;
2007 		memcpy(buffer, "OneDrive", err);
2008 		goto out;
2009 
2010 	default:
2011 		if (IsReparseTagMicrosoft(rp->ReparseTag)) {
2012 			/* Unknown Microsoft Tag. */
2013 			goto out;
2014 		}
2015 		if (!IsReparseTagNameSurrogate(rp->ReparseTag) ||
2016 		    size <= sizeof(struct REPARSE_POINT)) {
2017 			goto out;
2018 		}
2019 
2020 		/* Users tag. */
2021 		uname = Add2Ptr(rp, sizeof(struct REPARSE_POINT));
2022 		ulen = le16_to_cpu(rp->ReparseDataLength) -
2023 		       sizeof(struct REPARSE_POINT);
2024 	}
2025 
2026 	/* Convert nlen from bytes to UNICODE chars. */
2027 	ulen >>= 1;
2028 
2029 	/* Check that name is available. */
2030 	if (!ulen || uname + ulen > (__le16 *)Add2Ptr(rp, size))
2031 		goto out;
2032 
2033 	/* If name is already zero terminated then truncate it now. */
2034 	if (!uname[ulen - 1])
2035 		ulen -= 1;
2036 
2037 	err = ntfs_utf16_to_nls(sbi, uname, ulen, buffer, buflen);
2038 
2039 	if (err < 0)
2040 		goto out;
2041 
2042 	/* Translate Windows '\' into Linux '/'. */
2043 	for (i = 0; i < err; i++) {
2044 		if (buffer[i] == '\\')
2045 			buffer[i] = '/';
2046 	}
2047 
2048 	/* Always set last zero. */
2049 	buffer[err] = 0;
2050 
2051 	/* If this is a junction, translate the link target. */
2052 	if (rp->ReparseTag == IO_REPARSE_TAG_MOUNT_POINT)
2053 		err = ntfs_translate_junction(sb, link_de, buffer, err, buflen);
2054 
2055 out:
2056 	kfree(to_free);
2057 	return err;
2058 }
2059 
ntfs_get_link(struct dentry * de,struct inode * inode,struct delayed_call * done)2060 static const char *ntfs_get_link(struct dentry *de, struct inode *inode,
2061 				 struct delayed_call *done)
2062 {
2063 	int err;
2064 	char *ret;
2065 
2066 	if (!de)
2067 		return ERR_PTR(-ECHILD);
2068 
2069 	ret = kmalloc(PAGE_SIZE, GFP_NOFS);
2070 	if (!ret)
2071 		return ERR_PTR(-ENOMEM);
2072 
2073 	err = ntfs_readlink_hlp(de, inode, ret, PAGE_SIZE);
2074 	if (err < 0) {
2075 		kfree(ret);
2076 		return ERR_PTR(err);
2077 	}
2078 
2079 	set_delayed_call(done, kfree_link, ret);
2080 
2081 	return ret;
2082 }
2083 
2084 // clang-format off
2085 const struct inode_operations ntfs_link_inode_operations = {
2086 	.get_link	= ntfs_get_link,
2087 	.setattr	= ntfs_setattr,
2088 	.listxattr	= ntfs_listxattr,
2089 };
2090 
2091 const struct address_space_operations ntfs_aops = {
2092 	.read_folio	= ntfs_read_folio,
2093 	.readahead	= ntfs_readahead,
2094 	.writepages	= ntfs_writepages,
2095 	.write_begin	= ntfs_write_begin,
2096 	.write_end	= ntfs_write_end,
2097 	.direct_IO	= ntfs_direct_IO,
2098 	.bmap		= ntfs_bmap,
2099 	.dirty_folio	= block_dirty_folio,
2100 	.migrate_folio	= buffer_migrate_folio,
2101 	.invalidate_folio = block_invalidate_folio,
2102 };
2103 
2104 const struct address_space_operations ntfs_aops_cmpr = {
2105 	.read_folio	= ntfs_read_folio,
2106 	.readahead	= ntfs_readahead,
2107 	.dirty_folio	= block_dirty_folio,
2108 };
2109 // clang-format on
2110