xref: /linux/fs/isofs/inode.c (revision e7c375b181600caf135cfd03eadbc45eb530f2cb)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  *  linux/fs/isofs/inode.c
4  *
5  *  (C) 1991  Linus Torvalds - minix filesystem
6  *      1992, 1993, 1994  Eric Youngdale Modified for ISO 9660 filesystem.
7  *      1994  Eberhard Mönkeberg - multi session handling.
8  *      1995  Mark Dobie - allow mounting of some weird VideoCDs and PhotoCDs.
9  *	1997  Gordon Chaffee - Joliet CDs
10  *	1998  Eric Lammerts - ISO 9660 Level 3
11  *	2004  Paul Serice - Inode Support pushed out from 4GB to 128GB
12  *	2004  Paul Serice - NFS Export Operations
13  */
14 
15 #include <linux/init.h>
16 #include <linux/module.h>
17 
18 #include <linux/slab.h>
19 #include <linux/cred.h>
20 #include <linux/nls.h>
21 #include <linux/ctype.h>
22 #include <linux/statfs.h>
23 #include <linux/cdrom.h>
24 #include <linux/mpage.h>
25 #include <linux/user_namespace.h>
26 #include <linux/seq_file.h>
27 #include <linux/blkdev.h>
28 #include <linux/fs_context.h>
29 #include <linux/fs_parser.h>
30 
31 #include "isofs.h"
32 #include "zisofs.h"
33 
34 /* max tz offset is 13 hours */
35 #define MAX_TZ_OFFSET (52*15*60)
36 
37 #define BEQUIET
38 
39 static int isofs_hashi(const struct dentry *parent, struct qstr *qstr);
40 static int isofs_dentry_cmpi(const struct dentry *dentry,
41 		unsigned int len, const char *str, const struct qstr *name);
42 
43 #ifdef CONFIG_JOLIET
44 static int isofs_hashi_ms(const struct dentry *parent, struct qstr *qstr);
45 static int isofs_hash_ms(const struct dentry *parent, struct qstr *qstr);
46 static int isofs_dentry_cmpi_ms(const struct dentry *dentry,
47 		unsigned int len, const char *str, const struct qstr *name);
48 static int isofs_dentry_cmp_ms(const struct dentry *dentry,
49 		unsigned int len, const char *str, const struct qstr *name);
50 #endif
51 
isofs_put_super(struct super_block * sb)52 static void isofs_put_super(struct super_block *sb)
53 {
54 	struct isofs_sb_info *sbi = ISOFS_SB(sb);
55 
56 #ifdef CONFIG_JOLIET
57 	unload_nls(sbi->s_nls_iocharset);
58 #endif
59 
60 	kfree(sbi);
61 	sb->s_fs_info = NULL;
62 	return;
63 }
64 
65 static int isofs_read_inode(struct inode *, int relocated);
66 static int isofs_statfs (struct dentry *, struct kstatfs *);
67 static int isofs_show_options(struct seq_file *, struct dentry *);
68 
69 static struct kmem_cache *isofs_inode_cachep;
70 
isofs_alloc_inode(struct super_block * sb)71 static struct inode *isofs_alloc_inode(struct super_block *sb)
72 {
73 	struct iso_inode_info *ei;
74 	ei = alloc_inode_sb(sb, isofs_inode_cachep, GFP_KERNEL);
75 	if (!ei)
76 		return NULL;
77 	return &ei->vfs_inode;
78 }
79 
isofs_free_inode(struct inode * inode)80 static void isofs_free_inode(struct inode *inode)
81 {
82 	kmem_cache_free(isofs_inode_cachep, ISOFS_I(inode));
83 }
84 
init_once(void * foo)85 static void init_once(void *foo)
86 {
87 	struct iso_inode_info *ei = foo;
88 
89 	inode_init_once(&ei->vfs_inode);
90 }
91 
init_inodecache(void)92 static int __init init_inodecache(void)
93 {
94 	isofs_inode_cachep = kmem_cache_create("isofs_inode_cache",
95 					sizeof(struct iso_inode_info),
96 					0, (SLAB_RECLAIM_ACCOUNT|
97 					SLAB_ACCOUNT),
98 					init_once);
99 	if (!isofs_inode_cachep)
100 		return -ENOMEM;
101 	return 0;
102 }
103 
destroy_inodecache(void)104 static void destroy_inodecache(void)
105 {
106 	/*
107 	 * Make sure all delayed rcu free inodes are flushed before we
108 	 * destroy cache.
109 	 */
110 	rcu_barrier();
111 	kmem_cache_destroy(isofs_inode_cachep);
112 }
113 
isofs_reconfigure(struct fs_context * fc)114 static int isofs_reconfigure(struct fs_context *fc)
115 {
116 	sync_filesystem(fc->root->d_sb);
117 	if (!(fc->sb_flags & SB_RDONLY))
118 		return -EROFS;
119 	return 0;
120 }
121 
122 static const struct super_operations isofs_sops = {
123 	.alloc_inode	= isofs_alloc_inode,
124 	.free_inode	= isofs_free_inode,
125 	.put_super	= isofs_put_super,
126 	.statfs		= isofs_statfs,
127 	.show_options	= isofs_show_options,
128 };
129 
130 
131 static const struct dentry_operations isofs_dentry_ops[] = {
132 	{
133 		.d_hash		= isofs_hashi,
134 		.d_compare	= isofs_dentry_cmpi,
135 	},
136 #ifdef CONFIG_JOLIET
137 	{
138 		.d_hash		= isofs_hash_ms,
139 		.d_compare	= isofs_dentry_cmp_ms,
140 	},
141 	{
142 		.d_hash		= isofs_hashi_ms,
143 		.d_compare	= isofs_dentry_cmpi_ms,
144 	},
145 #endif
146 };
147 
148 struct isofs_options{
149 	unsigned int rock:1;
150 	unsigned int joliet:1;
151 	unsigned int cruft:1;
152 	unsigned int hide:1;
153 	unsigned int showassoc:1;
154 	unsigned int nocompress:1;
155 	unsigned int overriderockperm:1;
156 	unsigned int uid_set:1;
157 	unsigned int gid_set:1;
158 	unsigned char map;
159 	unsigned char check;
160 	unsigned int blocksize;
161 	umode_t fmode;
162 	umode_t dmode;
163 	kgid_t gid;
164 	kuid_t uid;
165 	char *iocharset;
166 	/* LVE */
167 	s32 session;
168 	s32 sbsector;
169 };
170 
171 /*
172  * Compute the hash for the isofs name corresponding to the dentry.
173  */
174 static int
isofs_hashi_common(const struct dentry * dentry,struct qstr * qstr,int ms)175 isofs_hashi_common(const struct dentry *dentry, struct qstr *qstr, int ms)
176 {
177 	const char *name;
178 	int len;
179 	char c;
180 	unsigned long hash;
181 
182 	len = qstr->len;
183 	name = qstr->name;
184 	if (ms) {
185 		while (len && name[len-1] == '.')
186 			len--;
187 	}
188 
189 	hash = init_name_hash(dentry);
190 	while (len--) {
191 		c = tolower(*name++);
192 		hash = partial_name_hash(c, hash);
193 	}
194 	qstr->hash = end_name_hash(hash);
195 
196 	return 0;
197 }
198 
199 /*
200  * Compare of two isofs names.
201  */
isofs_dentry_cmp_common(unsigned int len,const char * str,const struct qstr * name,int ms,int ci)202 static int isofs_dentry_cmp_common(
203 		unsigned int len, const char *str,
204 		const struct qstr *name, int ms, int ci)
205 {
206 	int alen, blen;
207 
208 	/* A filename cannot end in '.' or we treat it like it has none */
209 	alen = name->len;
210 	blen = len;
211 	if (ms) {
212 		while (alen && name->name[alen-1] == '.')
213 			alen--;
214 		while (blen && str[blen-1] == '.')
215 			blen--;
216 	}
217 	if (alen == blen) {
218 		if (ci) {
219 			if (strncasecmp(name->name, str, alen) == 0)
220 				return 0;
221 		} else {
222 			if (strncmp(name->name, str, alen) == 0)
223 				return 0;
224 		}
225 	}
226 	return 1;
227 }
228 
229 static int
isofs_hashi(const struct dentry * dentry,struct qstr * qstr)230 isofs_hashi(const struct dentry *dentry, struct qstr *qstr)
231 {
232 	return isofs_hashi_common(dentry, qstr, 0);
233 }
234 
235 static int
isofs_dentry_cmpi(const struct dentry * dentry,unsigned int len,const char * str,const struct qstr * name)236 isofs_dentry_cmpi(const struct dentry *dentry,
237 		unsigned int len, const char *str, const struct qstr *name)
238 {
239 	return isofs_dentry_cmp_common(len, str, name, 0, 1);
240 }
241 
242 #ifdef CONFIG_JOLIET
243 /*
244  * Compute the hash for the isofs name corresponding to the dentry.
245  */
246 static int
isofs_hash_common(const struct dentry * dentry,struct qstr * qstr,int ms)247 isofs_hash_common(const struct dentry *dentry, struct qstr *qstr, int ms)
248 {
249 	const char *name;
250 	int len;
251 
252 	len = qstr->len;
253 	name = qstr->name;
254 	if (ms) {
255 		while (len && name[len-1] == '.')
256 			len--;
257 	}
258 
259 	qstr->hash = full_name_hash(dentry, name, len);
260 
261 	return 0;
262 }
263 
264 static int
isofs_hash_ms(const struct dentry * dentry,struct qstr * qstr)265 isofs_hash_ms(const struct dentry *dentry, struct qstr *qstr)
266 {
267 	return isofs_hash_common(dentry, qstr, 1);
268 }
269 
270 static int
isofs_hashi_ms(const struct dentry * dentry,struct qstr * qstr)271 isofs_hashi_ms(const struct dentry *dentry, struct qstr *qstr)
272 {
273 	return isofs_hashi_common(dentry, qstr, 1);
274 }
275 
276 static int
isofs_dentry_cmp_ms(const struct dentry * dentry,unsigned int len,const char * str,const struct qstr * name)277 isofs_dentry_cmp_ms(const struct dentry *dentry,
278 		unsigned int len, const char *str, const struct qstr *name)
279 {
280 	return isofs_dentry_cmp_common(len, str, name, 1, 0);
281 }
282 
283 static int
isofs_dentry_cmpi_ms(const struct dentry * dentry,unsigned int len,const char * str,const struct qstr * name)284 isofs_dentry_cmpi_ms(const struct dentry *dentry,
285 		unsigned int len, const char *str, const struct qstr *name)
286 {
287 	return isofs_dentry_cmp_common(len, str, name, 1, 1);
288 }
289 #endif
290 
291 enum {
292 	Opt_block, Opt_check, Opt_cruft, Opt_gid, Opt_ignore, Opt_iocharset,
293 	Opt_map, Opt_mode, Opt_nojoliet, Opt_norock, Opt_sb, Opt_session,
294 	Opt_uid, Opt_unhide, Opt_utf8, Opt_err, Opt_nocompress, Opt_hide,
295 	Opt_showassoc, Opt_dmode, Opt_overriderockperm,
296 };
297 
298 static const struct constant_table isofs_param_map[] = {
299 	{"acorn",	'a'},
300 	{"a",		'a'},
301 	{"normal",	'n'},
302 	{"n",		'n'},
303 	{"off",		'o'},
304 	{"o",		'o'},
305 	{}
306 };
307 
308 static const struct constant_table isofs_param_check[] = {
309 	{"relaxed",	'r'},
310 	{"r",		'r'},
311 	{"strict",	's'},
312 	{"s",		's'},
313 	{}
314 };
315 
316 static const struct fs_parameter_spec isofs_param_spec[] = {
317 	fsparam_flag	("norock",		Opt_norock),
318 	fsparam_flag	("nojoliet",		Opt_nojoliet),
319 	fsparam_flag	("unhide",		Opt_unhide),
320 	fsparam_flag	("hide",		Opt_hide),
321 	fsparam_flag	("showassoc",		Opt_showassoc),
322 	fsparam_flag	("cruft",		Opt_cruft),
323 	fsparam_flag	("utf8",		Opt_utf8),
324 	fsparam_string	("iocharset",		Opt_iocharset),
325 	fsparam_enum	("map",			Opt_map, isofs_param_map),
326 	fsparam_u32	("session",		Opt_session),
327 	fsparam_u32	("sbsector",		Opt_sb),
328 	fsparam_enum	("check",		Opt_check, isofs_param_check),
329 	fsparam_uid	("uid",			Opt_uid),
330 	fsparam_gid	("gid",			Opt_gid),
331 	/* Note: mode/dmode historically accepted %u not strictly %o */
332 	fsparam_u32	("mode",		Opt_mode),
333 	fsparam_u32	("dmode",		Opt_dmode),
334 	fsparam_flag	("overriderockperm",	Opt_overriderockperm),
335 	fsparam_u32	("block",		Opt_block),
336 	fsparam_string	("conv",		Opt_ignore),
337 	fsparam_flag	("nocompress",		Opt_nocompress),
338 	{}
339 };
340 
isofs_parse_param(struct fs_context * fc,struct fs_parameter * param)341 static int isofs_parse_param(struct fs_context *fc,
342 			       struct fs_parameter *param)
343 {
344 	struct isofs_options *popt = fc->fs_private;
345 	struct fs_parse_result result;
346 	int opt;
347 	unsigned int n;
348 
349 	/* There are no remountable options */
350 	if (fc->purpose == FS_CONTEXT_FOR_RECONFIGURE)
351 		return 0;
352 
353 	opt = fs_parse(fc, isofs_param_spec, param, &result);
354 	if (opt < 0)
355 		return opt;
356 
357 	switch (opt) {
358 	case Opt_norock:
359 		popt->rock = 0;
360 		break;
361 	case Opt_nojoliet:
362 		popt->joliet = 0;
363 		break;
364 	case Opt_hide:
365 		popt->hide = 1;
366 		break;
367 	case Opt_unhide:
368 	case Opt_showassoc:
369 		popt->showassoc = 1;
370 		break;
371 	case Opt_cruft:
372 		popt->cruft = 1;
373 		break;
374 #ifdef CONFIG_JOLIET
375 	case Opt_utf8:
376 		kfree(popt->iocharset);
377 		popt->iocharset = kstrdup("utf8", GFP_KERNEL);
378 		if (!popt->iocharset)
379 			return -ENOMEM;
380 		break;
381 	case Opt_iocharset:
382 		kfree(popt->iocharset);
383 		popt->iocharset = kstrdup(param->string, GFP_KERNEL);
384 		if (!popt->iocharset)
385 			return -ENOMEM;
386 		break;
387 #endif
388 	case Opt_map:
389 		popt->map = result.uint_32;
390 		break;
391 	case Opt_session:
392 		n = result.uint_32;
393 		/*
394 		 * Track numbers are supposed to be in range 1-99, the
395 		 * mount option starts indexing at 0.
396 		 */
397 		if (n >= 99)
398 			return -EINVAL;
399 		popt->session = n + 1;
400 		break;
401 	case Opt_sb:
402 		popt->sbsector = result.uint_32;
403 		break;
404 	case Opt_check:
405 		popt->check = result.uint_32;
406 		break;
407 	case Opt_ignore:
408 		break;
409 	case Opt_uid:
410 		popt->uid = result.uid;
411 		popt->uid_set = 1;
412 		break;
413 	case Opt_gid:
414 		popt->gid = result.gid;
415 		popt->gid_set = 1;
416 		break;
417 	case Opt_mode:
418 		popt->fmode = result.uint_32;
419 		break;
420 	case Opt_dmode:
421 		popt->dmode = result.uint_32;
422 		break;
423 	case Opt_overriderockperm:
424 		popt->overriderockperm = 1;
425 		break;
426 	case Opt_block:
427 		n = result.uint_32;
428 		if (n != 512 && n != 1024 && n != 2048)
429 			return -EINVAL;
430 		popt->blocksize = n;
431 		break;
432 	case Opt_nocompress:
433 		popt->nocompress = 1;
434 		break;
435 	default:
436 		return -EINVAL;
437 	}
438 	return 0;
439 }
440 
441 /*
442  * Display the mount options in /proc/mounts.
443  */
isofs_show_options(struct seq_file * m,struct dentry * root)444 static int isofs_show_options(struct seq_file *m, struct dentry *root)
445 {
446 	struct isofs_sb_info *sbi = ISOFS_SB(root->d_sb);
447 
448 	if (!sbi->s_rock)		seq_puts(m, ",norock");
449 	else if (!sbi->s_joliet_level)	seq_puts(m, ",nojoliet");
450 	if (sbi->s_cruft)		seq_puts(m, ",cruft");
451 	if (sbi->s_hide)		seq_puts(m, ",hide");
452 	if (sbi->s_nocompress)		seq_puts(m, ",nocompress");
453 	if (sbi->s_overriderockperm)	seq_puts(m, ",overriderockperm");
454 	if (sbi->s_showassoc)		seq_puts(m, ",showassoc");
455 
456 	if (sbi->s_check)		seq_printf(m, ",check=%c", sbi->s_check);
457 	if (sbi->s_mapping)		seq_printf(m, ",map=%c", sbi->s_mapping);
458 	if (sbi->s_session != 255)	seq_printf(m, ",session=%u", sbi->s_session - 1);
459 	if (sbi->s_sbsector != -1)	seq_printf(m, ",sbsector=%u", sbi->s_sbsector);
460 
461 	if (root->d_sb->s_blocksize != 1024)
462 		seq_printf(m, ",blocksize=%lu", root->d_sb->s_blocksize);
463 
464 	if (sbi->s_uid_set)
465 		seq_printf(m, ",uid=%u",
466 			   from_kuid_munged(&init_user_ns, sbi->s_uid));
467 	if (sbi->s_gid_set)
468 		seq_printf(m, ",gid=%u",
469 			   from_kgid_munged(&init_user_ns, sbi->s_gid));
470 
471 	if (sbi->s_dmode != ISOFS_INVALID_MODE)
472 		seq_printf(m, ",dmode=%o", sbi->s_dmode);
473 	if (sbi->s_fmode != ISOFS_INVALID_MODE)
474 		seq_printf(m, ",fmode=%o", sbi->s_fmode);
475 
476 #ifdef CONFIG_JOLIET
477 	if (sbi->s_nls_iocharset)
478 		seq_printf(m, ",iocharset=%s", sbi->s_nls_iocharset->charset);
479 	else
480 		seq_puts(m, ",iocharset=utf8");
481 #endif
482 	return 0;
483 }
484 
485 /*
486  * look if the driver can tell the multi session redirection value
487  *
488  * don't change this if you don't know what you do, please!
489  * Multisession is legal only with XA disks.
490  * A non-XA disk with more than one volume descriptor may do it right, but
491  * usually is written in a nowhere standardized "multi-partition" manner.
492  * Multisession uses absolute addressing (solely the first frame of the whole
493  * track is #0), multi-partition uses relative addressing (each first frame of
494  * each track is #0), and a track is not a session.
495  *
496  * A broken CDwriter software or drive firmware does not set new standards,
497  * at least not if conflicting with the existing ones.
498  *
499  * emoenke@gwdg.de
500  */
501 #define WE_OBEY_THE_WRITTEN_STANDARDS 1
502 
isofs_get_last_session(struct super_block * sb,s32 session)503 static unsigned int isofs_get_last_session(struct super_block *sb, s32 session)
504 {
505 	struct cdrom_device_info *cdi = disk_to_cdi(sb->s_bdev->bd_disk);
506 	unsigned int vol_desc_start = 0;
507 
508 	if (session > 0) {
509 		struct cdrom_tocentry te;
510 
511 		if (!cdi)
512 			return 0;
513 
514 		te.cdte_track = session;
515 		te.cdte_format = CDROM_LBA;
516 		if (cdrom_read_tocentry(cdi, &te) == 0) {
517 			printk(KERN_DEBUG "ISOFS: Session %d start %d type %d\n",
518 				session, te.cdte_addr.lba,
519 				te.cdte_ctrl & CDROM_DATA_TRACK);
520 			if ((te.cdte_ctrl & CDROM_DATA_TRACK) == 4)
521 				return te.cdte_addr.lba;
522 		}
523 
524 		printk(KERN_ERR "ISOFS: Invalid session number or type of track\n");
525 	}
526 
527 	if (cdi) {
528 		struct cdrom_multisession ms_info;
529 
530 		ms_info.addr_format = CDROM_LBA;
531 		if (cdrom_multisession(cdi, &ms_info) == 0) {
532 #if WE_OBEY_THE_WRITTEN_STANDARDS
533 			/* necessary for a valid ms_info.addr */
534 			if (ms_info.xa_flag)
535 #endif
536 				vol_desc_start = ms_info.addr.lba;
537 		}
538 	}
539 
540 	return vol_desc_start;
541 }
542 
543 /*
544  * Check if root directory is empty (has less than 3 files).
545  *
546  * Used to detect broken CDs where ISO root directory is empty but Joliet root
547  * directory is OK. If such CD has Rock Ridge extensions, they will be disabled
548  * (and Joliet used instead) or else no files would be visible.
549  */
rootdir_empty(struct super_block * sb,unsigned long block)550 static bool rootdir_empty(struct super_block *sb, unsigned long block)
551 {
552 	int offset = 0, files = 0, de_len;
553 	struct iso_directory_record *de;
554 	struct buffer_head *bh;
555 
556 	bh = sb_bread(sb, block);
557 	if (!bh)
558 		return true;
559 	while (files < 3) {
560 		de = (struct iso_directory_record *) (bh->b_data + offset);
561 		de_len = *(unsigned char *) de;
562 		if (de_len == 0)
563 			break;
564 		files++;
565 		offset += de_len;
566 	}
567 	brelse(bh);
568 	return files < 3;
569 }
570 
571 /*
572  * Initialize the superblock and read the root inode.
573  */
isofs_fill_super(struct super_block * s,struct fs_context * fc)574 static int isofs_fill_super(struct super_block *s, struct fs_context *fc)
575 {
576 	struct buffer_head *bh = NULL, *pri_bh = NULL;
577 	struct hs_primary_descriptor *h_pri = NULL;
578 	struct iso_primary_descriptor *pri = NULL;
579 	struct iso_supplementary_descriptor *sec = NULL;
580 	struct iso_directory_record *rootp;
581 	struct inode *inode;
582 	struct isofs_options *opt = fc->fs_private;
583 	struct isofs_sb_info *sbi;
584 	unsigned long first_data_zone;
585 	int joliet_level = 0;
586 	int iso_blknum, block;
587 	int orig_zonesize;
588 	int table, error = -EINVAL;
589 	unsigned int vol_desc_start;
590 	int silent = fc->sb_flags & SB_SILENT;
591 
592 	sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
593 	if (!sbi)
594 		return -ENOMEM;
595 	s->s_fs_info = sbi;
596 
597 	/*
598 	 * First of all, get the hardware blocksize for this device.
599 	 * If we don't know what it is, or the hardware blocksize is
600 	 * larger than the blocksize the user specified, then use
601 	 * that value.
602 	 */
603 	/*
604 	 * What if bugger tells us to go beyond page size?
605 	 */
606 	if (bdev_logical_block_size(s->s_bdev) > 2048) {
607 		printk(KERN_WARNING
608 		       "ISOFS: unsupported/invalid hardware sector size %d\n",
609 			bdev_logical_block_size(s->s_bdev));
610 		goto out_freesbi;
611 	}
612 	opt->blocksize = sb_min_blocksize(s, opt->blocksize);
613 	if (!opt->blocksize) {
614 		printk(KERN_ERR
615 		       "ISOFS: unable to set blocksize\n");
616 		goto out_freesbi;
617 	}
618 
619 	sbi->s_high_sierra = 0; /* default is iso9660 */
620 	sbi->s_session = opt->session;
621 	sbi->s_sbsector = opt->sbsector;
622 
623 	vol_desc_start = (opt->sbsector != -1) ?
624 		opt->sbsector : isofs_get_last_session(s, opt->session);
625 
626 	for (iso_blknum = vol_desc_start+16;
627 		iso_blknum < vol_desc_start+100; iso_blknum++) {
628 		struct hs_volume_descriptor *hdp;
629 		struct iso_volume_descriptor  *vdp;
630 
631 		block = iso_blknum << (ISOFS_BLOCK_BITS - s->s_blocksize_bits);
632 		if (!(bh = sb_bread(s, block)))
633 			goto out_no_read;
634 
635 		vdp = (struct iso_volume_descriptor *)bh->b_data;
636 		hdp = (struct hs_volume_descriptor *)bh->b_data;
637 
638 		/*
639 		 * Due to the overlapping physical location of the descriptors,
640 		 * ISO CDs can match hdp->id==HS_STANDARD_ID as well. To ensure
641 		 * proper identification in this case, we first check for ISO.
642 		 */
643 		if (strncmp (vdp->id, ISO_STANDARD_ID, sizeof vdp->id) == 0) {
644 			if (isonum_711(vdp->type) == ISO_VD_END)
645 				break;
646 			if (isonum_711(vdp->type) == ISO_VD_PRIMARY) {
647 				if (!pri) {
648 					pri = (struct iso_primary_descriptor *)vdp;
649 					/* Save the buffer in case we need it ... */
650 					pri_bh = bh;
651 					bh = NULL;
652 				}
653 			}
654 #ifdef CONFIG_JOLIET
655 			else if (isonum_711(vdp->type) == ISO_VD_SUPPLEMENTARY) {
656 				sec = (struct iso_supplementary_descriptor *)vdp;
657 				if (sec->escape[0] == 0x25 && sec->escape[1] == 0x2f) {
658 					if (opt->joliet) {
659 						if (sec->escape[2] == 0x40)
660 							joliet_level = 1;
661 						else if (sec->escape[2] == 0x43)
662 							joliet_level = 2;
663 						else if (sec->escape[2] == 0x45)
664 							joliet_level = 3;
665 
666 						printk(KERN_DEBUG "ISO 9660 Extensions: "
667 							"Microsoft Joliet Level %d\n",
668 							joliet_level);
669 					}
670 					goto root_found;
671 				} else {
672 				/* Unknown supplementary volume descriptor */
673 				sec = NULL;
674 				}
675 			}
676 #endif
677 		} else {
678 			if (strncmp (hdp->id, HS_STANDARD_ID, sizeof hdp->id) == 0) {
679 				if (isonum_711(hdp->type) != ISO_VD_PRIMARY)
680 					goto out_freebh;
681 
682 				sbi->s_high_sierra = 1;
683 				opt->rock = 0;
684 				h_pri = (struct hs_primary_descriptor *)vdp;
685 				goto root_found;
686 			}
687 		}
688 
689 		/* Just skip any volume descriptors we don't recognize */
690 
691 		brelse(bh);
692 		bh = NULL;
693 	}
694 	/*
695 	 * If we fall through, either no volume descriptor was found,
696 	 * or else we passed a primary descriptor looking for others.
697 	 */
698 	if (!pri)
699 		goto out_unknown_format;
700 	brelse(bh);
701 	bh = pri_bh;
702 	pri_bh = NULL;
703 
704 root_found:
705 	/* We don't support read-write mounts */
706 	if (!sb_rdonly(s)) {
707 		error = -EACCES;
708 		goto out_freebh;
709 	}
710 
711 	if (joliet_level && (!pri || !opt->rock)) {
712 		/* This is the case of Joliet with the norock mount flag.
713 		 * A disc with both Joliet and Rock Ridge is handled later
714 		 */
715 		pri = (struct iso_primary_descriptor *) sec;
716 	}
717 
718 	if(sbi->s_high_sierra){
719 		rootp = (struct iso_directory_record *) h_pri->root_directory_record;
720 		sbi->s_nzones = isonum_733(h_pri->volume_space_size);
721 		sbi->s_log_zone_size = isonum_723(h_pri->logical_block_size);
722 		sbi->s_max_size = isonum_733(h_pri->volume_space_size);
723 	} else {
724 		if (!pri)
725 			goto out_freebh;
726 		rootp = (struct iso_directory_record *) pri->root_directory_record;
727 		sbi->s_nzones = isonum_733(pri->volume_space_size);
728 		sbi->s_log_zone_size = isonum_723(pri->logical_block_size);
729 		sbi->s_max_size = isonum_733(pri->volume_space_size);
730 	}
731 
732 	sbi->s_ninodes = 0; /* No way to figure this out easily */
733 
734 	orig_zonesize = sbi->s_log_zone_size;
735 	/*
736 	 * If the zone size is smaller than the hardware sector size,
737 	 * this is a fatal error.  This would occur if the disc drive
738 	 * had sectors that were 2048 bytes, but the filesystem had
739 	 * blocks that were 512 bytes (which should only very rarely
740 	 * happen.)
741 	 */
742 	if (orig_zonesize < opt->blocksize)
743 		goto out_bad_size;
744 
745 	/* RDE: convert log zone size to bit shift */
746 	switch (sbi->s_log_zone_size) {
747 	case  512: sbi->s_log_zone_size =  9; break;
748 	case 1024: sbi->s_log_zone_size = 10; break;
749 	case 2048: sbi->s_log_zone_size = 11; break;
750 
751 	default:
752 		goto out_bad_zone_size;
753 	}
754 
755 	s->s_magic = ISOFS_SUPER_MAGIC;
756 
757 	/*
758 	 * With multi-extent files, file size is only limited by the maximum
759 	 * size of a file system, which is 8 TB.
760 	 */
761 	s->s_maxbytes = 0x80000000000LL;
762 
763 	/* ECMA-119 timestamp from 1900/1/1 with tz offset */
764 	s->s_time_min = mktime64(1900, 1, 1, 0, 0, 0) - MAX_TZ_OFFSET;
765 	s->s_time_max = mktime64(U8_MAX+1900, 12, 31, 23, 59, 59) + MAX_TZ_OFFSET;
766 
767 	/* Set this for reference. Its not currently used except on write
768 	   which we don't have .. */
769 
770 	first_data_zone = isonum_733(rootp->extent) +
771 			  isonum_711(rootp->ext_attr_length);
772 	sbi->s_firstdatazone = first_data_zone;
773 #ifndef BEQUIET
774 	printk(KERN_DEBUG "ISOFS: Max size:%ld   Log zone size:%ld\n",
775 		sbi->s_max_size, 1UL << sbi->s_log_zone_size);
776 	printk(KERN_DEBUG "ISOFS: First datazone:%ld\n", sbi->s_firstdatazone);
777 	if(sbi->s_high_sierra)
778 		printk(KERN_DEBUG "ISOFS: Disc in High Sierra format.\n");
779 #endif
780 
781 	/*
782 	 * If the Joliet level is set, we _may_ decide to use the
783 	 * secondary descriptor, but can't be sure until after we
784 	 * read the root inode. But before reading the root inode
785 	 * we may need to change the device blocksize, and would
786 	 * rather release the old buffer first. So, we cache the
787 	 * first_data_zone value from the secondary descriptor.
788 	 */
789 	if (joliet_level) {
790 		pri = (struct iso_primary_descriptor *) sec;
791 		rootp = (struct iso_directory_record *)
792 			pri->root_directory_record;
793 		first_data_zone = isonum_733(rootp->extent) +
794 				isonum_711(rootp->ext_attr_length);
795 	}
796 
797 	/*
798 	 * We're all done using the volume descriptor, and may need
799 	 * to change the device blocksize, so release the buffer now.
800 	 */
801 	brelse(pri_bh);
802 	brelse(bh);
803 
804 	/*
805 	 * Force the blocksize to 512 for 512 byte sectors.  The file
806 	 * read primitives really get it wrong in a bad way if we don't
807 	 * do this.
808 	 *
809 	 * Note - we should never be setting the blocksize to something
810 	 * less than the hardware sector size for the device.  If we
811 	 * do, we would end up having to read larger buffers and split
812 	 * out portions to satisfy requests.
813 	 *
814 	 * Note2- the idea here is that we want to deal with the optimal
815 	 * zonesize in the filesystem.  If we have it set to something less,
816 	 * then we have horrible problems with trying to piece together
817 	 * bits of adjacent blocks in order to properly read directory
818 	 * entries.  By forcing the blocksize in this way, we ensure
819 	 * that we will never be required to do this.
820 	 */
821 	sb_set_blocksize(s, orig_zonesize);
822 
823 	sbi->s_nls_iocharset = NULL;
824 
825 #ifdef CONFIG_JOLIET
826 	if (joliet_level) {
827 		char *p = opt->iocharset ? opt->iocharset : CONFIG_NLS_DEFAULT;
828 		if (strcmp(p, "utf8") != 0) {
829 			sbi->s_nls_iocharset = opt->iocharset ?
830 				load_nls(opt->iocharset) : load_nls_default();
831 			if (!sbi->s_nls_iocharset)
832 				goto out_freesbi;
833 		}
834 	}
835 #endif
836 	s->s_op = &isofs_sops;
837 	s->s_export_op = &isofs_export_ops;
838 	sbi->s_mapping = opt->map;
839 	sbi->s_rock = (opt->rock ? 2 : 0);
840 	sbi->s_rock_offset = -1; /* initial offset, will guess until SP is found*/
841 	sbi->s_cruft = opt->cruft;
842 	sbi->s_hide = opt->hide;
843 	sbi->s_showassoc = opt->showassoc;
844 	sbi->s_uid = opt->uid;
845 	sbi->s_gid = opt->gid;
846 	sbi->s_uid_set = opt->uid_set;
847 	sbi->s_gid_set = opt->gid_set;
848 	sbi->s_nocompress = opt->nocompress;
849 	sbi->s_overriderockperm = opt->overriderockperm;
850 	/*
851 	 * It would be incredibly stupid to allow people to mark every file
852 	 * on the disk as suid, so we merely allow them to set the default
853 	 * permissions.
854 	 */
855 	if (opt->fmode != ISOFS_INVALID_MODE)
856 		sbi->s_fmode = opt->fmode & 0777;
857 	else
858 		sbi->s_fmode = ISOFS_INVALID_MODE;
859 	if (opt->dmode != ISOFS_INVALID_MODE)
860 		sbi->s_dmode = opt->dmode & 0777;
861 	else
862 		sbi->s_dmode = ISOFS_INVALID_MODE;
863 
864 	/*
865 	 * Read the root inode, which _may_ result in changing
866 	 * the s_rock flag. Once we have the final s_rock value,
867 	 * we then decide whether to use the Joliet descriptor.
868 	 */
869 	inode = isofs_iget(s, sbi->s_firstdatazone, 0);
870 
871 	/*
872 	 * Fix for broken CDs with a corrupt root inode but a correct Joliet
873 	 * root directory.
874 	 */
875 	if (IS_ERR(inode)) {
876 		if (joliet_level && sbi->s_firstdatazone != first_data_zone) {
877 			printk(KERN_NOTICE
878 			       "ISOFS: root inode is unusable. "
879 			       "Disabling Rock Ridge and switching to Joliet.");
880 			sbi->s_rock = 0;
881 			inode = NULL;
882 		} else {
883 			goto out_no_root;
884 		}
885 	}
886 
887 	/*
888 	 * Fix for broken CDs with Rock Ridge and empty ISO root directory but
889 	 * correct Joliet root directory.
890 	 */
891 	if (sbi->s_rock == 1 && joliet_level &&
892 				rootdir_empty(s, sbi->s_firstdatazone)) {
893 		printk(KERN_NOTICE
894 			"ISOFS: primary root directory is empty. "
895 			"Disabling Rock Ridge and switching to Joliet.");
896 		sbi->s_rock = 0;
897 	}
898 
899 	/*
900 	 * If this disk has both Rock Ridge and Joliet on it, then we
901 	 * want to use Rock Ridge by default.  This can be overridden
902 	 * by using the norock mount option.  There is still one other
903 	 * possibility that is not taken into account: a Rock Ridge
904 	 * CD with Unicode names.  Until someone sees such a beast, it
905 	 * will not be supported.
906 	 */
907 	if (sbi->s_rock == 1) {
908 		joliet_level = 0;
909 	} else if (joliet_level) {
910 		sbi->s_rock = 0;
911 		if (sbi->s_firstdatazone != first_data_zone) {
912 			sbi->s_firstdatazone = first_data_zone;
913 			printk(KERN_DEBUG
914 				"ISOFS: changing to secondary root\n");
915 			iput(inode);
916 			inode = isofs_iget(s, sbi->s_firstdatazone, 0);
917 			if (IS_ERR(inode))
918 				goto out_no_root;
919 		}
920 	}
921 
922 	if (opt->check == 'u') {
923 		/* Only Joliet is case insensitive by default */
924 		if (joliet_level)
925 			opt->check = 'r';
926 		else
927 			opt->check = 's';
928 	}
929 	sbi->s_joliet_level = joliet_level;
930 
931 	/* Make sure the root inode is a directory */
932 	if (!S_ISDIR(inode->i_mode)) {
933 		printk(KERN_WARNING
934 			"isofs_fill_super: root inode is not a directory. "
935 			"Corrupted media?\n");
936 		goto out_iput;
937 	}
938 
939 	table = 0;
940 	if (joliet_level)
941 		table += 2;
942 	if (opt->check == 'r')
943 		table++;
944 	sbi->s_check = opt->check;
945 
946 	if (table)
947 		set_default_d_op(s, &isofs_dentry_ops[table - 1]);
948 
949 	/* get the root dentry */
950 	s->s_root = d_make_root(inode);
951 	if (!(s->s_root)) {
952 		error = -ENOMEM;
953 		goto out_no_inode;
954 	}
955 
956 	return 0;
957 
958 	/*
959 	 * Display error messages and free resources.
960 	 */
961 out_iput:
962 	iput(inode);
963 	goto out_no_inode;
964 out_no_root:
965 	error = PTR_ERR(inode);
966 	if (error != -ENOMEM)
967 		printk(KERN_WARNING "%s: get root inode failed\n", __func__);
968 out_no_inode:
969 #ifdef CONFIG_JOLIET
970 	unload_nls(sbi->s_nls_iocharset);
971 #endif
972 	goto out_freesbi;
973 out_no_read:
974 	printk(KERN_WARNING "%s: bread failed, dev=%s, iso_blknum=%d, block=%d\n",
975 		__func__, s->s_id, iso_blknum, block);
976 	goto out_freebh;
977 out_bad_zone_size:
978 	printk(KERN_WARNING "ISOFS: Bad logical zone size %ld\n",
979 		sbi->s_log_zone_size);
980 	goto out_freebh;
981 out_bad_size:
982 	printk(KERN_WARNING "ISOFS: Logical zone size(%d) < hardware blocksize(%u)\n",
983 		orig_zonesize, opt->blocksize);
984 	goto out_freebh;
985 out_unknown_format:
986 	if (!silent)
987 		printk(KERN_WARNING "ISOFS: Unable to identify CD-ROM format.\n");
988 
989 out_freebh:
990 	brelse(bh);
991 	brelse(pri_bh);
992 out_freesbi:
993 	kfree(sbi);
994 	s->s_fs_info = NULL;
995 	return error;
996 }
997 
isofs_statfs(struct dentry * dentry,struct kstatfs * buf)998 static int isofs_statfs (struct dentry *dentry, struct kstatfs *buf)
999 {
1000 	struct super_block *sb = dentry->d_sb;
1001 	u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
1002 
1003 	buf->f_type = ISOFS_SUPER_MAGIC;
1004 	buf->f_bsize = sb->s_blocksize;
1005 	buf->f_blocks = (ISOFS_SB(sb)->s_nzones
1006 		<< (ISOFS_SB(sb)->s_log_zone_size - sb->s_blocksize_bits));
1007 	buf->f_bfree = 0;
1008 	buf->f_bavail = 0;
1009 	buf->f_files = ISOFS_SB(sb)->s_ninodes;
1010 	buf->f_ffree = 0;
1011 	buf->f_fsid = u64_to_fsid(id);
1012 	buf->f_namelen = NAME_MAX;
1013 	return 0;
1014 }
1015 
1016 /*
1017  * Get a set of blocks; filling in buffer_heads if already allocated
1018  * or getblk() if they are not.  Returns the number of blocks inserted
1019  * (-ve == error.)
1020  */
isofs_get_blocks(struct inode * inode,sector_t iblock,struct buffer_head ** bh,unsigned long nblocks)1021 int isofs_get_blocks(struct inode *inode, sector_t iblock,
1022 		     struct buffer_head **bh, unsigned long nblocks)
1023 {
1024 	unsigned long b_off = iblock;
1025 	unsigned offset, sect_size;
1026 	unsigned int firstext;
1027 	unsigned long nextblk, nextoff;
1028 	int section, rv, error;
1029 	struct iso_inode_info *ei = ISOFS_I(inode);
1030 
1031 	error = -EIO;
1032 	rv = 0;
1033 	if (iblock != b_off) {
1034 		printk(KERN_DEBUG "%s: block number too large\n", __func__);
1035 		goto abort;
1036 	}
1037 
1038 
1039 	offset = 0;
1040 	firstext = ei->i_first_extent;
1041 	sect_size = ei->i_section_size >> ISOFS_BUFFER_BITS(inode);
1042 	nextblk = ei->i_next_section_block;
1043 	nextoff = ei->i_next_section_offset;
1044 	section = 0;
1045 
1046 	while (nblocks) {
1047 		/* If we are *way* beyond the end of the file, print a message.
1048 		 * Access beyond the end of the file up to the next page boundary
1049 		 * is normal, however because of the way the page cache works.
1050 		 * In this case, we just return 0 so that we can properly fill
1051 		 * the page with useless information without generating any
1052 		 * I/O errors.
1053 		 */
1054 		if (b_off > ((inode->i_size + PAGE_SIZE - 1) >> ISOFS_BUFFER_BITS(inode))) {
1055 			printk(KERN_DEBUG "%s: block >= EOF (%lu, %llu)\n",
1056 				__func__, b_off,
1057 				(unsigned long long)inode->i_size);
1058 			goto abort;
1059 		}
1060 
1061 		/* On the last section, nextblk == 0, section size is likely to
1062 		 * exceed sect_size by a partial block, and access beyond the
1063 		 * end of the file will reach beyond the section size, too.
1064 		 */
1065 		while (nextblk && (b_off >= (offset + sect_size))) {
1066 			struct inode *ninode;
1067 
1068 			offset += sect_size;
1069 			ninode = isofs_iget(inode->i_sb, nextblk, nextoff);
1070 			if (IS_ERR(ninode)) {
1071 				error = PTR_ERR(ninode);
1072 				goto abort;
1073 			}
1074 			firstext  = ISOFS_I(ninode)->i_first_extent;
1075 			sect_size = ISOFS_I(ninode)->i_section_size >> ISOFS_BUFFER_BITS(ninode);
1076 			nextblk   = ISOFS_I(ninode)->i_next_section_block;
1077 			nextoff   = ISOFS_I(ninode)->i_next_section_offset;
1078 			iput(ninode);
1079 
1080 			if (++section > 100) {
1081 				printk(KERN_DEBUG "%s: More than 100 file sections ?!?"
1082 					" aborting...\n", __func__);
1083 				printk(KERN_DEBUG "%s: block=%lu firstext=%u sect_size=%u "
1084 					"nextblk=%lu nextoff=%lu\n", __func__,
1085 					b_off, firstext, (unsigned) sect_size,
1086 					nextblk, nextoff);
1087 				goto abort;
1088 			}
1089 		}
1090 
1091 		if (*bh) {
1092 			map_bh(*bh, inode->i_sb, firstext + b_off - offset);
1093 		} else {
1094 			*bh = sb_getblk(inode->i_sb, firstext+b_off-offset);
1095 			if (!*bh)
1096 				goto abort;
1097 		}
1098 		bh++;	/* Next buffer head */
1099 		b_off++;	/* Next buffer offset */
1100 		nblocks--;
1101 		rv++;
1102 	}
1103 
1104 	error = 0;
1105 abort:
1106 	return rv != 0 ? rv : error;
1107 }
1108 
1109 /*
1110  * Used by the standard interfaces.
1111  */
isofs_get_block(struct inode * inode,sector_t iblock,struct buffer_head * bh_result,int create)1112 static int isofs_get_block(struct inode *inode, sector_t iblock,
1113 		    struct buffer_head *bh_result, int create)
1114 {
1115 	int ret;
1116 
1117 	if (create) {
1118 		printk(KERN_DEBUG "%s: Kernel tries to allocate a block\n", __func__);
1119 		return -EROFS;
1120 	}
1121 
1122 	ret = isofs_get_blocks(inode, iblock, &bh_result, 1);
1123 	return ret < 0 ? ret : 0;
1124 }
1125 
isofs_bmap(struct inode * inode,sector_t block)1126 static int isofs_bmap(struct inode *inode, sector_t block)
1127 {
1128 	struct buffer_head dummy;
1129 	int error;
1130 
1131 	dummy.b_state = 0;
1132 	dummy.b_blocknr = -1000;
1133 	error = isofs_get_block(inode, block, &dummy, 0);
1134 	if (!error)
1135 		return dummy.b_blocknr;
1136 	return 0;
1137 }
1138 
isofs_bread(struct inode * inode,sector_t block)1139 struct buffer_head *isofs_bread(struct inode *inode, sector_t block)
1140 {
1141 	sector_t blknr = isofs_bmap(inode, block);
1142 	if (!blknr)
1143 		return NULL;
1144 	return sb_bread(inode->i_sb, blknr);
1145 }
1146 
isofs_read_folio(struct file * file,struct folio * folio)1147 static int isofs_read_folio(struct file *file, struct folio *folio)
1148 {
1149 	return mpage_read_folio(folio, isofs_get_block);
1150 }
1151 
isofs_readahead(struct readahead_control * rac)1152 static void isofs_readahead(struct readahead_control *rac)
1153 {
1154 	mpage_readahead(rac, isofs_get_block);
1155 }
1156 
_isofs_bmap(struct address_space * mapping,sector_t block)1157 static sector_t _isofs_bmap(struct address_space *mapping, sector_t block)
1158 {
1159 	return generic_block_bmap(mapping,block,isofs_get_block);
1160 }
1161 
1162 static const struct address_space_operations isofs_aops = {
1163 	.read_folio = isofs_read_folio,
1164 	.readahead = isofs_readahead,
1165 	.bmap = _isofs_bmap
1166 };
1167 
isofs_read_level3_size(struct inode * inode)1168 static int isofs_read_level3_size(struct inode *inode)
1169 {
1170 	unsigned long bufsize = ISOFS_BUFFER_SIZE(inode);
1171 	int high_sierra = ISOFS_SB(inode->i_sb)->s_high_sierra;
1172 	struct buffer_head *bh = NULL;
1173 	unsigned long block, offset, block_saved, offset_saved;
1174 	int i = 0;
1175 	int more_entries = 0;
1176 	struct iso_directory_record *tmpde = NULL;
1177 	struct iso_inode_info *ei = ISOFS_I(inode);
1178 
1179 	inode->i_size = 0;
1180 
1181 	/* The first 16 blocks are reserved as the System Area.  Thus,
1182 	 * no inodes can appear in block 0.  We use this to flag that
1183 	 * this is the last section. */
1184 	ei->i_next_section_block = 0;
1185 	ei->i_next_section_offset = 0;
1186 
1187 	block = ei->i_iget5_block;
1188 	offset = ei->i_iget5_offset;
1189 
1190 	do {
1191 		struct iso_directory_record *de;
1192 		unsigned int de_len;
1193 
1194 		if (!bh) {
1195 			bh = sb_bread(inode->i_sb, block);
1196 			if (!bh)
1197 				goto out_noread;
1198 		}
1199 		de = (struct iso_directory_record *) (bh->b_data + offset);
1200 		de_len = *(unsigned char *) de;
1201 
1202 		if (de_len == 0) {
1203 			brelse(bh);
1204 			bh = NULL;
1205 			++block;
1206 			offset = 0;
1207 			continue;
1208 		}
1209 
1210 		block_saved = block;
1211 		offset_saved = offset;
1212 		offset += de_len;
1213 
1214 		/* Make sure we have a full directory entry */
1215 		if (offset >= bufsize) {
1216 			int slop = bufsize - offset + de_len;
1217 			if (!tmpde) {
1218 				tmpde = kmalloc(256, GFP_KERNEL);
1219 				if (!tmpde)
1220 					goto out_nomem;
1221 			}
1222 			memcpy(tmpde, de, slop);
1223 			offset &= bufsize - 1;
1224 			block++;
1225 			brelse(bh);
1226 			bh = NULL;
1227 			if (offset) {
1228 				bh = sb_bread(inode->i_sb, block);
1229 				if (!bh)
1230 					goto out_noread;
1231 				memcpy((void *)tmpde+slop, bh->b_data, offset);
1232 			}
1233 			de = tmpde;
1234 		}
1235 
1236 		inode->i_size += isonum_733(de->size);
1237 		if (i == 1) {
1238 			ei->i_next_section_block = block_saved;
1239 			ei->i_next_section_offset = offset_saved;
1240 		}
1241 
1242 		more_entries = de->flags[-high_sierra] & 0x80;
1243 
1244 		i++;
1245 		if (i > 100)
1246 			goto out_toomany;
1247 	} while (more_entries);
1248 out:
1249 	kfree(tmpde);
1250 	brelse(bh);
1251 	return 0;
1252 
1253 out_nomem:
1254 	brelse(bh);
1255 	return -ENOMEM;
1256 
1257 out_noread:
1258 	printk(KERN_INFO "ISOFS: unable to read i-node block %lu\n", block);
1259 	kfree(tmpde);
1260 	return -EIO;
1261 
1262 out_toomany:
1263 	printk(KERN_INFO "%s: More than 100 file sections ?!?, aborting...\n"
1264 		"isofs_read_level3_size: inode=%lu\n",
1265 		__func__, inode->i_ino);
1266 	goto out;
1267 }
1268 
isofs_read_inode(struct inode * inode,int relocated)1269 static int isofs_read_inode(struct inode *inode, int relocated)
1270 {
1271 	struct super_block *sb = inode->i_sb;
1272 	struct isofs_sb_info *sbi = ISOFS_SB(sb);
1273 	unsigned long bufsize = ISOFS_BUFFER_SIZE(inode);
1274 	unsigned long block;
1275 	int high_sierra = sbi->s_high_sierra;
1276 	struct buffer_head *bh;
1277 	struct iso_directory_record *de;
1278 	struct iso_directory_record *tmpde = NULL;
1279 	unsigned int de_len;
1280 	unsigned long offset;
1281 	struct iso_inode_info *ei = ISOFS_I(inode);
1282 	int ret = -EIO;
1283 	struct timespec64 ts;
1284 
1285 	block = ei->i_iget5_block;
1286 	bh = sb_bread(inode->i_sb, block);
1287 	if (!bh)
1288 		goto out_badread;
1289 
1290 	offset = ei->i_iget5_offset;
1291 
1292 	de = (struct iso_directory_record *) (bh->b_data + offset);
1293 	de_len = *(unsigned char *) de;
1294 	if (de_len < sizeof(struct iso_directory_record))
1295 		goto fail;
1296 
1297 	if (offset + de_len > bufsize) {
1298 		int frag1 = bufsize - offset;
1299 
1300 		tmpde = kmalloc(de_len, GFP_KERNEL);
1301 		if (!tmpde) {
1302 			ret = -ENOMEM;
1303 			goto fail;
1304 		}
1305 		memcpy(tmpde, bh->b_data + offset, frag1);
1306 		brelse(bh);
1307 		bh = sb_bread(inode->i_sb, ++block);
1308 		if (!bh)
1309 			goto out_badread;
1310 		memcpy((char *)tmpde+frag1, bh->b_data, de_len - frag1);
1311 		de = tmpde;
1312 	}
1313 
1314 	inode->i_ino = isofs_get_ino(ei->i_iget5_block,
1315 					ei->i_iget5_offset,
1316 					ISOFS_BUFFER_BITS(inode));
1317 
1318 	/* Assume it is a normal-format file unless told otherwise */
1319 	ei->i_file_format = isofs_file_normal;
1320 
1321 	if (de->flags[-high_sierra] & 2) {
1322 		if (sbi->s_dmode != ISOFS_INVALID_MODE)
1323 			inode->i_mode = S_IFDIR | sbi->s_dmode;
1324 		else
1325 			inode->i_mode = S_IFDIR | S_IRUGO | S_IXUGO;
1326 		set_nlink(inode, 1);	/*
1327 					 * Set to 1.  We know there are 2, but
1328 					 * the find utility tries to optimize
1329 					 * if it is 2, and it screws up.  It is
1330 					 * easier to give 1 which tells find to
1331 					 * do it the hard way.
1332 					 */
1333 	} else {
1334 		if (sbi->s_fmode != ISOFS_INVALID_MODE) {
1335 			inode->i_mode = S_IFREG | sbi->s_fmode;
1336 		} else {
1337 			/*
1338 			 * Set default permissions: r-x for all.  The disc
1339 			 * could be shared with DOS machines so virtually
1340 			 * anything could be a valid executable.
1341 			 */
1342 			inode->i_mode = S_IFREG | S_IRUGO | S_IXUGO;
1343 		}
1344 		set_nlink(inode, 1);
1345 	}
1346 	inode->i_uid = sbi->s_uid;
1347 	inode->i_gid = sbi->s_gid;
1348 	inode->i_blocks = 0;
1349 
1350 	ei->i_format_parm[0] = 0;
1351 	ei->i_format_parm[1] = 0;
1352 	ei->i_format_parm[2] = 0;
1353 
1354 	ei->i_section_size = isonum_733(de->size);
1355 	if (de->flags[-high_sierra] & 0x80) {
1356 		ret = isofs_read_level3_size(inode);
1357 		if (ret < 0)
1358 			goto fail;
1359 		ret = -EIO;
1360 	} else {
1361 		ei->i_next_section_block = 0;
1362 		ei->i_next_section_offset = 0;
1363 		inode->i_size = isonum_733(de->size);
1364 	}
1365 
1366 	/*
1367 	 * Some dipshit decided to store some other bit of information
1368 	 * in the high byte of the file length.  Truncate size in case
1369 	 * this CDROM was mounted with the cruft option.
1370 	 */
1371 
1372 	if (sbi->s_cruft)
1373 		inode->i_size &= 0x00ffffff;
1374 
1375 	if (de->interleave[0]) {
1376 		printk(KERN_DEBUG "ISOFS: Interleaved files not (yet) supported.\n");
1377 		inode->i_size = 0;
1378 	}
1379 
1380 	/* I have no idea what file_unit_size is used for, so
1381 	   we will flag it for now */
1382 	if (de->file_unit_size[0] != 0) {
1383 		printk(KERN_DEBUG "ISOFS: File unit size != 0 for ISO file (%ld).\n",
1384 			inode->i_ino);
1385 	}
1386 
1387 	/* I have no idea what other flag bits are used for, so
1388 	   we will flag it for now */
1389 #ifdef DEBUG
1390 	if((de->flags[-high_sierra] & ~2)!= 0){
1391 		printk(KERN_DEBUG "ISOFS: Unusual flag settings for ISO file "
1392 				"(%ld %x).\n",
1393 			inode->i_ino, de->flags[-high_sierra]);
1394 	}
1395 #endif
1396 	ts = iso_date(de->date, high_sierra ? ISO_DATE_HIGH_SIERRA : 0);
1397 	inode_set_ctime_to_ts(inode, ts);
1398 	inode_set_atime_to_ts(inode, ts);
1399 	inode_set_mtime_to_ts(inode, ts);
1400 
1401 	ei->i_first_extent = (isonum_733(de->extent) +
1402 			isonum_711(de->ext_attr_length));
1403 
1404 	/* Set the number of blocks for stat() - should be done before RR */
1405 	inode->i_blocks = (inode->i_size + 511) >> 9;
1406 
1407 	/*
1408 	 * Now test for possible Rock Ridge extensions which will override
1409 	 * some of these numbers in the inode structure.
1410 	 */
1411 
1412 	if (!high_sierra) {
1413 		parse_rock_ridge_inode(de, inode, relocated);
1414 		/* if we want uid/gid set, override the rock ridge setting */
1415 		if (sbi->s_uid_set)
1416 			inode->i_uid = sbi->s_uid;
1417 		if (sbi->s_gid_set)
1418 			inode->i_gid = sbi->s_gid;
1419 	}
1420 	/* Now set final access rights if overriding rock ridge setting */
1421 	if (S_ISDIR(inode->i_mode) && sbi->s_overriderockperm &&
1422 	    sbi->s_dmode != ISOFS_INVALID_MODE)
1423 		inode->i_mode = S_IFDIR | sbi->s_dmode;
1424 	if (S_ISREG(inode->i_mode) && sbi->s_overriderockperm &&
1425 	    sbi->s_fmode != ISOFS_INVALID_MODE)
1426 		inode->i_mode = S_IFREG | sbi->s_fmode;
1427 
1428 	/* Install the inode operations vector */
1429 	if (S_ISREG(inode->i_mode)) {
1430 		inode->i_fop = &generic_ro_fops;
1431 		switch (ei->i_file_format) {
1432 #ifdef CONFIG_ZISOFS
1433 		case isofs_file_compressed:
1434 			inode->i_data.a_ops = &zisofs_aops;
1435 			break;
1436 #endif
1437 		default:
1438 			inode->i_data.a_ops = &isofs_aops;
1439 			break;
1440 		}
1441 	} else if (S_ISDIR(inode->i_mode)) {
1442 		inode->i_op = &isofs_dir_inode_operations;
1443 		inode->i_fop = &isofs_dir_operations;
1444 	} else if (S_ISLNK(inode->i_mode)) {
1445 		inode->i_op = &page_symlink_inode_operations;
1446 		inode_nohighmem(inode);
1447 		inode->i_data.a_ops = &isofs_symlink_aops;
1448 	} else if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode) ||
1449 		   S_ISFIFO(inode->i_mode) || S_ISSOCK(inode->i_mode)) {
1450 		/* XXX - parse_rock_ridge_inode() had already set i_rdev. */
1451 		init_special_inode(inode, inode->i_mode, inode->i_rdev);
1452 	} else {
1453 		printk(KERN_DEBUG "ISOFS: Invalid file type 0%04o for inode %lu.\n",
1454 			inode->i_mode, inode->i_ino);
1455 		ret = -EIO;
1456 		goto fail;
1457 	}
1458 
1459 	ret = 0;
1460 out:
1461 	kfree(tmpde);
1462 	brelse(bh);
1463 	return ret;
1464 
1465 out_badread:
1466 	printk(KERN_WARNING "ISOFS: unable to read i-node block\n");
1467 fail:
1468 	goto out;
1469 }
1470 
1471 struct isofs_iget5_callback_data {
1472 	unsigned long block;
1473 	unsigned long offset;
1474 };
1475 
isofs_iget5_test(struct inode * ino,void * data)1476 static int isofs_iget5_test(struct inode *ino, void *data)
1477 {
1478 	struct iso_inode_info *i = ISOFS_I(ino);
1479 	struct isofs_iget5_callback_data *d =
1480 		(struct isofs_iget5_callback_data*)data;
1481 	return (i->i_iget5_block == d->block)
1482 		&& (i->i_iget5_offset == d->offset);
1483 }
1484 
isofs_iget5_set(struct inode * ino,void * data)1485 static int isofs_iget5_set(struct inode *ino, void *data)
1486 {
1487 	struct iso_inode_info *i = ISOFS_I(ino);
1488 	struct isofs_iget5_callback_data *d =
1489 		(struct isofs_iget5_callback_data*)data;
1490 	i->i_iget5_block = d->block;
1491 	i->i_iget5_offset = d->offset;
1492 	return 0;
1493 }
1494 
1495 /* Store, in the inode's containing structure, the block and block
1496  * offset that point to the underlying meta-data for the inode.  The
1497  * code below is otherwise similar to the iget() code in
1498  * include/linux/fs.h */
__isofs_iget(struct super_block * sb,unsigned long block,unsigned long offset,int relocated)1499 struct inode *__isofs_iget(struct super_block *sb,
1500 			   unsigned long block,
1501 			   unsigned long offset,
1502 			   int relocated)
1503 {
1504 	unsigned long hashval;
1505 	struct inode *inode;
1506 	struct isofs_iget5_callback_data data;
1507 	long ret;
1508 
1509 	if (offset >= 1ul << sb->s_blocksize_bits)
1510 		return ERR_PTR(-EINVAL);
1511 
1512 	data.block = block;
1513 	data.offset = offset;
1514 
1515 	hashval = (block << sb->s_blocksize_bits) | offset;
1516 
1517 	inode = iget5_locked(sb, hashval, &isofs_iget5_test,
1518 				&isofs_iget5_set, &data);
1519 
1520 	if (!inode)
1521 		return ERR_PTR(-ENOMEM);
1522 
1523 	if (inode->i_state & I_NEW) {
1524 		ret = isofs_read_inode(inode, relocated);
1525 		if (ret < 0) {
1526 			iget_failed(inode);
1527 			inode = ERR_PTR(ret);
1528 		} else {
1529 			unlock_new_inode(inode);
1530 		}
1531 	}
1532 
1533 	return inode;
1534 }
1535 
isofs_get_tree(struct fs_context * fc)1536 static int isofs_get_tree(struct fs_context *fc)
1537 {
1538 	return get_tree_bdev(fc, isofs_fill_super);
1539 }
1540 
isofs_free_fc(struct fs_context * fc)1541 static void isofs_free_fc(struct fs_context *fc)
1542 {
1543 	struct isofs_options *opt = fc->fs_private;
1544 
1545 	kfree(opt->iocharset);
1546 	kfree(opt);
1547 }
1548 
1549 static const struct fs_context_operations isofs_context_ops = {
1550 	.parse_param	= isofs_parse_param,
1551 	.get_tree	= isofs_get_tree,
1552 	.reconfigure	= isofs_reconfigure,
1553 	.free		= isofs_free_fc,
1554 };
1555 
isofs_init_fs_context(struct fs_context * fc)1556 static int isofs_init_fs_context(struct fs_context *fc)
1557 {
1558 	struct isofs_options *opt;
1559 
1560 	opt = kzalloc(sizeof(*opt), GFP_KERNEL);
1561 	if (!opt)
1562 		return -ENOMEM;
1563 
1564 	opt->map = 'n';
1565 	opt->rock = 1;
1566 	opt->joliet = 1;
1567 	opt->cruft = 0;
1568 	opt->hide = 0;
1569 	opt->showassoc = 0;
1570 	opt->check = 'u';		/* unset */
1571 	opt->nocompress = 0;
1572 	opt->blocksize = 1024;
1573 	opt->fmode = opt->dmode = ISOFS_INVALID_MODE;
1574 	opt->uid_set = 0;
1575 	opt->gid_set = 0;
1576 	opt->gid = GLOBAL_ROOT_GID;
1577 	opt->uid = GLOBAL_ROOT_UID;
1578 	opt->iocharset = NULL;
1579 	opt->overriderockperm = 0;
1580 	opt->session = -1;
1581 	opt->sbsector = -1;
1582 
1583 	fc->fs_private = opt;
1584 	fc->ops = &isofs_context_ops;
1585 
1586 	return 0;
1587 }
1588 
1589 static struct file_system_type iso9660_fs_type = {
1590 	.owner		= THIS_MODULE,
1591 	.name		= "iso9660",
1592 	.kill_sb	= kill_block_super,
1593 	.fs_flags	= FS_REQUIRES_DEV,
1594 	.init_fs_context = isofs_init_fs_context,
1595 	.parameters	= isofs_param_spec,
1596 };
1597 MODULE_ALIAS_FS("iso9660");
1598 MODULE_ALIAS("iso9660");
1599 
init_iso9660_fs(void)1600 static int __init init_iso9660_fs(void)
1601 {
1602 	int err = init_inodecache();
1603 	if (err)
1604 		goto out;
1605 #ifdef CONFIG_ZISOFS
1606 	err = zisofs_init();
1607 	if (err)
1608 		goto out1;
1609 #endif
1610 	err = register_filesystem(&iso9660_fs_type);
1611 	if (err)
1612 		goto out2;
1613 	return 0;
1614 out2:
1615 #ifdef CONFIG_ZISOFS
1616 	zisofs_cleanup();
1617 out1:
1618 #endif
1619 	destroy_inodecache();
1620 out:
1621 	return err;
1622 }
1623 
exit_iso9660_fs(void)1624 static void __exit exit_iso9660_fs(void)
1625 {
1626         unregister_filesystem(&iso9660_fs_type);
1627 #ifdef CONFIG_ZISOFS
1628 	zisofs_cleanup();
1629 #endif
1630 	destroy_inodecache();
1631 }
1632 
1633 module_init(init_iso9660_fs)
1634 module_exit(exit_iso9660_fs)
1635 MODULE_DESCRIPTION("ISO 9660 CDROM file system support");
1636 MODULE_LICENSE("GPL");
1637