blob: 98b3eb7d8eaf64d5eb006801aeb130ff8503f593 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * linux/fs/isofs/rock.c
3 *
4 * (C) 1992, 1993 Eric Youngdale
5 *
6 * Rock Ridge Extensions to iso9660
7 */
8
Linus Torvalds1da177e2005-04-16 15:20:36 -07009#include <linux/slab.h>
10#include <linux/pagemap.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070011
Al Viro94f2f7152005-04-25 18:32:12 -070012#include "isofs.h"
Linus Torvalds1da177e2005-04-16 15:20:36 -070013#include "rock.h"
14
Andrew Morton73739092005-06-21 17:16:47 -070015/*
16 * These functions are designed to read the system areas of a directory record
Linus Torvalds1da177e2005-04-16 15:20:36 -070017 * and extract relevant information. There are different functions provided
18 * depending upon what information we need at the time. One function fills
19 * out an inode structure, a second one extracts a filename, a third one
20 * returns a symbolic link name, and a fourth one returns the extent number
Andrew Morton73739092005-06-21 17:16:47 -070021 * for the file.
22 */
Linus Torvalds1da177e2005-04-16 15:20:36 -070023
Andrew Morton1d372112005-06-21 17:16:42 -070024#define SIG(A,B) ((A) | ((B) << 8)) /* isonum_721() */
Linus Torvalds1da177e2005-04-16 15:20:36 -070025
Andrew Mortonba40aaf2005-06-21 17:16:46 -070026struct rock_state {
27 void *buffer;
28 unsigned char *chr;
29 int len;
30 int cont_size;
31 int cont_extent;
32 int cont_offset;
Jan Karaf54e18f2014-12-15 14:22:46 +010033 int cont_loops;
Andrew Mortonba40aaf2005-06-21 17:16:46 -070034 struct inode *inode;
35};
36
Andrew Morton12121712005-06-21 17:16:44 -070037/*
38 * This is a way of ensuring that we have something in the system
Andrew Morton73739092005-06-21 17:16:47 -070039 * use fields that is compatible with Rock Ridge. Return zero on success.
Andrew Morton12121712005-06-21 17:16:44 -070040 */
41
42static int check_sp(struct rock_ridge *rr, struct inode *inode)
43{
44 if (rr->u.SP.magic[0] != 0xbe)
45 return -1;
46 if (rr->u.SP.magic[1] != 0xef)
47 return -1;
48 ISOFS_SB(inode->i_sb)->s_rock_offset = rr->u.SP.skip;
49 return 0;
50}
51
Andrew Morton76ab07e2005-06-21 17:16:46 -070052static void setup_rock_ridge(struct iso_directory_record *de,
Andrew Mortonba40aaf2005-06-21 17:16:46 -070053 struct inode *inode, struct rock_state *rs)
Andrew Morton76ab07e2005-06-21 17:16:46 -070054{
Andrew Mortonba40aaf2005-06-21 17:16:46 -070055 rs->len = sizeof(struct iso_directory_record) + de->name_len[0];
56 if (rs->len & 1)
57 (rs->len)++;
58 rs->chr = (unsigned char *)de + rs->len;
59 rs->len = *((unsigned char *)de) - rs->len;
60 if (rs->len < 0)
61 rs->len = 0;
Andrew Morton76ab07e2005-06-21 17:16:46 -070062
63 if (ISOFS_SB(inode->i_sb)->s_rock_offset != -1) {
Andrew Mortonba40aaf2005-06-21 17:16:46 -070064 rs->len -= ISOFS_SB(inode->i_sb)->s_rock_offset;
65 rs->chr += ISOFS_SB(inode->i_sb)->s_rock_offset;
66 if (rs->len < 0)
67 rs->len = 0;
Andrew Morton76ab07e2005-06-21 17:16:46 -070068 }
Andrew Morton1d372112005-06-21 17:16:42 -070069}
Linus Torvalds1da177e2005-04-16 15:20:36 -070070
Andrew Mortonba40aaf2005-06-21 17:16:46 -070071static void init_rock_state(struct rock_state *rs, struct inode *inode)
72{
73 memset(rs, 0, sizeof(*rs));
74 rs->inode = inode;
75}
76
Jan Karaf54e18f2014-12-15 14:22:46 +010077/* Maximum number of Rock Ridge continuation entries */
78#define RR_MAX_CE_ENTRIES 32
79
Andrew Mortonba40aaf2005-06-21 17:16:46 -070080/*
81 * Returns 0 if the caller should continue scanning, 1 if the scan must end
82 * and -ve on error.
83 */
84static int rock_continue(struct rock_state *rs)
85{
86 int ret = 1;
Andrew Mortone5954472005-06-21 17:16:50 -070087 int blocksize = 1 << rs->inode->i_blkbits;
88 const int min_de_size = offsetof(struct rock_ridge, u);
Andrew Mortonba40aaf2005-06-21 17:16:46 -070089
90 kfree(rs->buffer);
91 rs->buffer = NULL;
Andrew Mortone5954472005-06-21 17:16:50 -070092
93 if ((unsigned)rs->cont_offset > blocksize - min_de_size ||
94 (unsigned)rs->cont_size > blocksize ||
95 (unsigned)(rs->cont_offset + rs->cont_size) > blocksize) {
96 printk(KERN_NOTICE "rock: corrupted directory entry. "
97 "extent=%d, offset=%d, size=%d\n",
98 rs->cont_extent, rs->cont_offset, rs->cont_size);
99 ret = -EIO;
100 goto out;
101 }
102
Andrew Mortonba40aaf2005-06-21 17:16:46 -0700103 if (rs->cont_extent) {
104 struct buffer_head *bh;
105
106 rs->buffer = kmalloc(rs->cont_size, GFP_KERNEL);
107 if (!rs->buffer) {
108 ret = -ENOMEM;
109 goto out;
110 }
111 ret = -EIO;
Jan Karaf54e18f2014-12-15 14:22:46 +0100112 if (++rs->cont_loops >= RR_MAX_CE_ENTRIES)
113 goto out;
Andrew Mortonba40aaf2005-06-21 17:16:46 -0700114 bh = sb_bread(rs->inode->i_sb, rs->cont_extent);
115 if (bh) {
116 memcpy(rs->buffer, bh->b_data + rs->cont_offset,
117 rs->cont_size);
118 put_bh(bh);
119 rs->chr = rs->buffer;
120 rs->len = rs->cont_size;
121 rs->cont_extent = 0;
122 rs->cont_size = 0;
123 rs->cont_offset = 0;
124 return 0;
125 }
126 printk("Unable to read rock-ridge attributes\n");
127 }
128out:
129 kfree(rs->buffer);
130 rs->buffer = NULL;
131 return ret;
132}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700133
Andrew Morton73739092005-06-21 17:16:47 -0700134/*
Andrew Mortonf2966632005-06-21 17:16:51 -0700135 * We think there's a record of type `sig' at rs->chr. Parse the signature
136 * and make sure that there's really room for a record of that type.
137 */
138static int rock_check_overflow(struct rock_state *rs, int sig)
139{
140 int len;
141
142 switch (sig) {
143 case SIG('S', 'P'):
144 len = sizeof(struct SU_SP_s);
145 break;
146 case SIG('C', 'E'):
147 len = sizeof(struct SU_CE_s);
148 break;
149 case SIG('E', 'R'):
150 len = sizeof(struct SU_ER_s);
151 break;
152 case SIG('R', 'R'):
153 len = sizeof(struct RR_RR_s);
154 break;
155 case SIG('P', 'X'):
156 len = sizeof(struct RR_PX_s);
157 break;
158 case SIG('P', 'N'):
159 len = sizeof(struct RR_PN_s);
160 break;
161 case SIG('S', 'L'):
162 len = sizeof(struct RR_SL_s);
163 break;
164 case SIG('N', 'M'):
165 len = sizeof(struct RR_NM_s);
166 break;
167 case SIG('C', 'L'):
168 len = sizeof(struct RR_CL_s);
169 break;
170 case SIG('P', 'L'):
171 len = sizeof(struct RR_PL_s);
172 break;
173 case SIG('T', 'F'):
174 len = sizeof(struct RR_TF_s);
175 break;
176 case SIG('Z', 'F'):
177 len = sizeof(struct RR_ZF_s);
178 break;
179 default:
180 len = 0;
181 break;
182 }
183 len += offsetof(struct rock_ridge, u);
184 if (len > rs->len) {
185 printk(KERN_NOTICE "rock: directory entry would overflow "
186 "storage\n");
187 printk(KERN_NOTICE "rock: sig=0x%02x, size=%d, remaining=%d\n",
188 sig, len, rs->len);
189 return -EIO;
190 }
191 return 0;
192}
193
194/*
Andrew Morton73739092005-06-21 17:16:47 -0700195 * return length of name field; 0: not found, -1: to be ignored
196 */
Andrew Morton1d372112005-06-21 17:16:42 -0700197int get_rock_ridge_filename(struct iso_directory_record *de,
198 char *retname, struct inode *inode)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700199{
Andrew Mortonba40aaf2005-06-21 17:16:46 -0700200 struct rock_state rs;
Andrew Morton7fa393a2005-06-21 17:16:43 -0700201 struct rock_ridge *rr;
202 int sig;
203 int retnamlen = 0;
204 int truncate = 0;
Andrew Mortonba40aaf2005-06-21 17:16:46 -0700205 int ret = 0;
Al Viro99d82582016-05-05 16:25:35 -0400206 char *p;
207 int len;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700208
Andrew Morton1d372112005-06-21 17:16:42 -0700209 if (!ISOFS_SB(inode->i_sb)->s_rock)
210 return 0;
211 *retname = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700212
Andrew Mortonba40aaf2005-06-21 17:16:46 -0700213 init_rock_state(&rs, inode);
214 setup_rock_ridge(de, inode, &rs);
Andrew Morton7fa393a2005-06-21 17:16:43 -0700215repeat:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700216
Andrew Mortonba40aaf2005-06-21 17:16:46 -0700217 while (rs.len > 2) { /* There may be one byte for padding somewhere */
218 rr = (struct rock_ridge *)rs.chr;
Adam Greenblattc0a16332008-07-25 01:46:32 -0700219 /*
220 * Ignore rock ridge info if rr->len is out of range, but
221 * don't return -EIO because that would make the file
222 * invisible.
223 */
Andrew Morton7fa393a2005-06-21 17:16:43 -0700224 if (rr->len < 3)
225 goto out; /* Something got screwed up here */
Andrew Mortonba40aaf2005-06-21 17:16:46 -0700226 sig = isonum_721(rs.chr);
Andrew Mortonf2966632005-06-21 17:16:51 -0700227 if (rock_check_overflow(&rs, sig))
228 goto eio;
Andrew Mortonba40aaf2005-06-21 17:16:46 -0700229 rs.chr += rr->len;
230 rs.len -= rr->len;
Adam Greenblattc0a16332008-07-25 01:46:32 -0700231 /*
232 * As above, just ignore the rock ridge info if rr->len
233 * is bogus.
234 */
Andrew Mortonba40aaf2005-06-21 17:16:46 -0700235 if (rs.len < 0)
Adam Greenblattc0a16332008-07-25 01:46:32 -0700236 goto out; /* Something got screwed up here */
Andrew Morton1d372112005-06-21 17:16:42 -0700237
Andrew Morton7fa393a2005-06-21 17:16:43 -0700238 switch (sig) {
239 case SIG('R', 'R'):
240 if ((rr->u.RR.flags[0] & RR_NM) == 0)
241 goto out;
242 break;
243 case SIG('S', 'P'):
Andrew Morton12121712005-06-21 17:16:44 -0700244 if (check_sp(rr, inode))
245 goto out;
Andrew Morton7fa393a2005-06-21 17:16:43 -0700246 break;
247 case SIG('C', 'E'):
Andrew Mortonba40aaf2005-06-21 17:16:46 -0700248 rs.cont_extent = isonum_733(rr->u.CE.extent);
249 rs.cont_offset = isonum_733(rr->u.CE.offset);
250 rs.cont_size = isonum_733(rr->u.CE.size);
Andrew Morton7fa393a2005-06-21 17:16:43 -0700251 break;
252 case SIG('N', 'M'):
253 if (truncate)
Andrew Morton1d372112005-06-21 17:16:42 -0700254 break;
Andrew Morton7fa393a2005-06-21 17:16:43 -0700255 if (rr->len < 5)
Andrew Morton1d372112005-06-21 17:16:42 -0700256 break;
Andrew Morton7fa393a2005-06-21 17:16:43 -0700257 /*
258 * If the flags are 2 or 4, this indicates '.' or '..'.
259 * We don't want to do anything with this, because it
260 * screws up the code that calls us. We don't really
261 * care anyways, since we can just use the non-RR
262 * name.
263 */
264 if (rr->u.NM.flags & 6)
Andrew Morton1d372112005-06-21 17:16:42 -0700265 break;
Andrew Morton1d372112005-06-21 17:16:42 -0700266
Andrew Morton7fa393a2005-06-21 17:16:43 -0700267 if (rr->u.NM.flags & ~1) {
268 printk("Unsupported NM flag settings (%d)\n",
269 rr->u.NM.flags);
Andrew Morton1d372112005-06-21 17:16:42 -0700270 break;
271 }
Al Viro99d82582016-05-05 16:25:35 -0400272 len = rr->len - 5;
273 if (retnamlen + len >= 254) {
Andrew Morton7fa393a2005-06-21 17:16:43 -0700274 truncate = 1;
275 break;
276 }
Al Viro99d82582016-05-05 16:25:35 -0400277 p = memchr(rr->u.NM.name, '\0', len);
278 if (unlikely(p))
279 len = p - rr->u.NM.name;
280 memcpy(retname + retnamlen, rr->u.NM.name, len);
281 retnamlen += len;
282 retname[retnamlen] = '\0';
Andrew Morton7fa393a2005-06-21 17:16:43 -0700283 break;
284 case SIG('R', 'E'):
Andrew Mortonba40aaf2005-06-21 17:16:46 -0700285 kfree(rs.buffer);
Andrew Morton7fa393a2005-06-21 17:16:43 -0700286 return -1;
287 default:
288 break;
Andrew Morton1d372112005-06-21 17:16:42 -0700289 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700290 }
Andrew Mortonba40aaf2005-06-21 17:16:46 -0700291 ret = rock_continue(&rs);
292 if (ret == 0)
293 goto repeat;
294 if (ret == 1)
295 return retnamlen; /* If 0, this file did not have a NM field */
Andrew Morton7fa393a2005-06-21 17:16:43 -0700296out:
Andrew Mortonba40aaf2005-06-21 17:16:46 -0700297 kfree(rs.buffer);
298 return ret;
Andrew Mortonf2966632005-06-21 17:16:51 -0700299eio:
300 ret = -EIO;
301 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700302}
303
Jan Kara410dd3c2014-08-17 11:49:57 +0200304#define RR_REGARD_XA 1
305#define RR_RELOC_DE 2
306
Linus Torvalds1da177e2005-04-16 15:20:36 -0700307static int
308parse_rock_ridge_inode_internal(struct iso_directory_record *de,
Jan Kara410dd3c2014-08-17 11:49:57 +0200309 struct inode *inode, int flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700310{
Andrew Morton1d372112005-06-21 17:16:42 -0700311 int symlink_len = 0;
Andrew Morton7fa393a2005-06-21 17:16:43 -0700312 int cnt, sig;
Jan Kara410dd3c2014-08-17 11:49:57 +0200313 unsigned int reloc_block;
Andrew Morton7fa393a2005-06-21 17:16:43 -0700314 struct inode *reloc;
315 struct rock_ridge *rr;
316 int rootflag;
Andrew Mortonba40aaf2005-06-21 17:16:46 -0700317 struct rock_state rs;
318 int ret = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700319
Andrew Morton1d372112005-06-21 17:16:42 -0700320 if (!ISOFS_SB(inode->i_sb)->s_rock)
321 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700322
Andrew Mortonba40aaf2005-06-21 17:16:46 -0700323 init_rock_state(&rs, inode);
324 setup_rock_ridge(de, inode, &rs);
Jan Kara410dd3c2014-08-17 11:49:57 +0200325 if (flags & RR_REGARD_XA) {
Andrew Mortonba40aaf2005-06-21 17:16:46 -0700326 rs.chr += 14;
327 rs.len -= 14;
328 if (rs.len < 0)
329 rs.len = 0;
Andrew Morton1d372112005-06-21 17:16:42 -0700330 }
331
Andrew Morton7fa393a2005-06-21 17:16:43 -0700332repeat:
Andrew Mortonba40aaf2005-06-21 17:16:46 -0700333 while (rs.len > 2) { /* There may be one byte for padding somewhere */
334 rr = (struct rock_ridge *)rs.chr;
Adam Greenblattc0a16332008-07-25 01:46:32 -0700335 /*
336 * Ignore rock ridge info if rr->len is out of range, but
337 * don't return -EIO because that would make the file
338 * invisible.
339 */
Andrew Morton7fa393a2005-06-21 17:16:43 -0700340 if (rr->len < 3)
341 goto out; /* Something got screwed up here */
Andrew Mortonba40aaf2005-06-21 17:16:46 -0700342 sig = isonum_721(rs.chr);
Andrew Mortonf2966632005-06-21 17:16:51 -0700343 if (rock_check_overflow(&rs, sig))
344 goto eio;
Andrew Mortonba40aaf2005-06-21 17:16:46 -0700345 rs.chr += rr->len;
346 rs.len -= rr->len;
Adam Greenblattc0a16332008-07-25 01:46:32 -0700347 /*
348 * As above, just ignore the rock ridge info if rr->len
349 * is bogus.
350 */
Andrew Mortonba40aaf2005-06-21 17:16:46 -0700351 if (rs.len < 0)
Adam Greenblattc0a16332008-07-25 01:46:32 -0700352 goto out; /* Something got screwed up here */
Andrew Morton1d372112005-06-21 17:16:42 -0700353
Andrew Morton7fa393a2005-06-21 17:16:43 -0700354 switch (sig) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700355#ifndef CONFIG_ZISOFS /* No flag for SF or ZF */
Andrew Morton7fa393a2005-06-21 17:16:43 -0700356 case SIG('R', 'R'):
357 if ((rr->u.RR.flags[0] &
358 (RR_PX | RR_TF | RR_SL | RR_CL)) == 0)
Andrew Morton1d372112005-06-21 17:16:42 -0700359 goto out;
Andrew Morton7fa393a2005-06-21 17:16:43 -0700360 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700361#endif
Andrew Morton7fa393a2005-06-21 17:16:43 -0700362 case SIG('S', 'P'):
Andrew Morton12121712005-06-21 17:16:44 -0700363 if (check_sp(rr, inode))
364 goto out;
Andrew Morton7fa393a2005-06-21 17:16:43 -0700365 break;
366 case SIG('C', 'E'):
Andrew Mortonba40aaf2005-06-21 17:16:46 -0700367 rs.cont_extent = isonum_733(rr->u.CE.extent);
368 rs.cont_offset = isonum_733(rr->u.CE.offset);
369 rs.cont_size = isonum_733(rr->u.CE.size);
Andrew Morton7fa393a2005-06-21 17:16:43 -0700370 break;
371 case SIG('E', 'R'):
Jan Kara4e202462014-12-18 17:26:10 +0100372 /* Invalid length of ER tag id? */
373 if (rr->u.ER.len_id + offsetof(struct rock_ridge, u.ER.data) > rr->len)
374 goto out;
Andrew Morton7fa393a2005-06-21 17:16:43 -0700375 ISOFS_SB(inode->i_sb)->s_rock = 1;
376 printk(KERN_DEBUG "ISO 9660 Extensions: ");
377 {
378 int p;
379 for (p = 0; p < rr->u.ER.len_id; p++)
380 printk("%c", rr->u.ER.data[p]);
Andrew Morton1d372112005-06-21 17:16:42 -0700381 }
Andrew Morton7fa393a2005-06-21 17:16:43 -0700382 printk("\n");
383 break;
384 case SIG('P', 'X'):
385 inode->i_mode = isonum_733(rr->u.PX.mode);
Miklos Szeredibfe86842011-10-28 14:13:29 +0200386 set_nlink(inode, isonum_733(rr->u.PX.n_links));
Eric W. Biedermanba64e2b2012-02-10 11:35:50 -0800387 i_uid_write(inode, isonum_733(rr->u.PX.uid));
388 i_gid_write(inode, isonum_733(rr->u.PX.gid));
Andrew Morton7fa393a2005-06-21 17:16:43 -0700389 break;
390 case SIG('P', 'N'):
391 {
392 int high, low;
393 high = isonum_733(rr->u.PN.dev_high);
394 low = isonum_733(rr->u.PN.dev_low);
395 /*
396 * The Rock Ridge standard specifies that if
397 * sizeof(dev_t) <= 4, then the high field is
398 * unused, and the device number is completely
399 * stored in the low field. Some writers may
400 * ignore this subtlety,
401 * and as a result we test to see if the entire
402 * device number is
403 * stored in the low field, and use that.
404 */
405 if ((low & ~0xff) && high == 0) {
406 inode->i_rdev =
407 MKDEV(low >> 8, low & 0xff);
408 } else {
409 inode->i_rdev =
410 MKDEV(high, low);
411 }
412 }
413 break;
414 case SIG('T', 'F'):
415 /*
416 * Some RRIP writers incorrectly place ctime in the
417 * TF_CREATE field. Try to handle this correctly for
418 * either case.
419 */
420 /* Rock ridge never appears on a High Sierra disk */
421 cnt = 0;
422 if (rr->u.TF.flags & TF_CREATE) {
423 inode->i_ctime.tv_sec =
424 iso_date(rr->u.TF.times[cnt++].time,
425 0);
426 inode->i_ctime.tv_nsec = 0;
427 }
428 if (rr->u.TF.flags & TF_MODIFY) {
429 inode->i_mtime.tv_sec =
430 iso_date(rr->u.TF.times[cnt++].time,
431 0);
432 inode->i_mtime.tv_nsec = 0;
433 }
434 if (rr->u.TF.flags & TF_ACCESS) {
435 inode->i_atime.tv_sec =
436 iso_date(rr->u.TF.times[cnt++].time,
437 0);
438 inode->i_atime.tv_nsec = 0;
439 }
440 if (rr->u.TF.flags & TF_ATTRIBUTES) {
441 inode->i_ctime.tv_sec =
442 iso_date(rr->u.TF.times[cnt++].time,
443 0);
444 inode->i_ctime.tv_nsec = 0;
445 }
446 break;
447 case SIG('S', 'L'):
448 {
449 int slen;
450 struct SL_component *slp;
451 struct SL_component *oldslp;
452 slen = rr->len - 5;
453 slp = &rr->u.SL.link;
454 inode->i_size = symlink_len;
455 while (slen > 1) {
456 rootflag = 0;
457 switch (slp->flags & ~1) {
458 case 0:
459 inode->i_size +=
460 slp->len;
461 break;
462 case 2:
463 inode->i_size += 1;
464 break;
465 case 4:
466 inode->i_size += 2;
467 break;
468 case 8:
469 rootflag = 1;
470 inode->i_size += 1;
471 break;
472 default:
473 printk("Symlink component flag "
474 "not implemented\n");
475 }
476 slen -= slp->len + 2;
477 oldslp = slp;
478 slp = (struct SL_component *)
479 (((char *)slp) + slp->len + 2);
480
481 if (slen < 2) {
482 if (((rr->u.SL.
483 flags & 1) != 0)
484 &&
485 ((oldslp->
486 flags & 1) == 0))
487 inode->i_size +=
488 1;
489 break;
490 }
491
492 /*
493 * If this component record isn't
494 * continued, then append a '/'.
495 */
496 if (!rootflag
497 && (oldslp->flags & 1) == 0)
498 inode->i_size += 1;
499 }
500 }
501 symlink_len = inode->i_size;
502 break;
503 case SIG('R', 'E'):
504 printk(KERN_WARNING "Attempt to read inode for "
505 "relocated directory\n");
506 goto out;
507 case SIG('C', 'L'):
Jan Kara410dd3c2014-08-17 11:49:57 +0200508 if (flags & RR_RELOC_DE) {
509 printk(KERN_ERR
510 "ISOFS: Recursive directory relocation "
511 "is not supported\n");
512 goto eio;
513 }
514 reloc_block = isonum_733(rr->u.CL.location);
515 if (reloc_block == ISOFS_I(inode)->i_iget5_block &&
516 ISOFS_I(inode)->i_iget5_offset == 0) {
517 printk(KERN_ERR
518 "ISOFS: Directory relocation points to "
519 "itself\n");
520 goto eio;
521 }
522 ISOFS_I(inode)->i_first_extent = reloc_block;
523 reloc = isofs_iget_reloc(inode->i_sb, reloc_block, 0);
David Howellsc4386c82008-02-07 00:15:41 -0800524 if (IS_ERR(reloc)) {
525 ret = PTR_ERR(reloc);
Andrew Morton7fa393a2005-06-21 17:16:43 -0700526 goto out;
David Howellsc4386c82008-02-07 00:15:41 -0800527 }
Andrew Morton7fa393a2005-06-21 17:16:43 -0700528 inode->i_mode = reloc->i_mode;
Miklos Szeredibfe86842011-10-28 14:13:29 +0200529 set_nlink(inode, reloc->i_nlink);
Andrew Morton7fa393a2005-06-21 17:16:43 -0700530 inode->i_uid = reloc->i_uid;
531 inode->i_gid = reloc->i_gid;
532 inode->i_rdev = reloc->i_rdev;
533 inode->i_size = reloc->i_size;
534 inode->i_blocks = reloc->i_blocks;
535 inode->i_atime = reloc->i_atime;
536 inode->i_ctime = reloc->i_ctime;
537 inode->i_mtime = reloc->i_mtime;
538 iput(reloc);
539 break;
540#ifdef CONFIG_ZISOFS
541 case SIG('Z', 'F'): {
542 int algo;
543
544 if (ISOFS_SB(inode->i_sb)->s_nocompress)
545 break;
546 algo = isonum_721(rr->u.ZF.algorithm);
547 if (algo == SIG('p', 'z')) {
548 int block_shift =
549 isonum_711(&rr->u.ZF.parms[1]);
Jan Kara59bc0552009-09-23 14:44:56 +0200550 if (block_shift > 17) {
Andrew Morton7fa393a2005-06-21 17:16:43 -0700551 printk(KERN_WARNING "isofs: "
552 "Can't handle ZF block "
553 "size of 2^%d\n",
554 block_shift);
555 } else {
556 /*
557 * Note: we don't change
558 * i_blocks here
559 */
560 ISOFS_I(inode)->i_file_format =
561 isofs_file_compressed;
562 /*
563 * Parameters to compression
564 * algorithm (header size,
565 * block size)
566 */
567 ISOFS_I(inode)->i_format_parm[0] =
568 isonum_711(&rr->u.ZF.parms[0]);
569 ISOFS_I(inode)->i_format_parm[1] =
570 isonum_711(&rr->u.ZF.parms[1]);
571 inode->i_size =
572 isonum_733(rr->u.ZF.
573 real_size);
574 }
575 } else {
576 printk(KERN_WARNING
577 "isofs: Unknown ZF compression "
578 "algorithm: %c%c\n",
579 rr->u.ZF.algorithm[0],
580 rr->u.ZF.algorithm[1]);
581 }
582 break;
583 }
584#endif
585 default:
586 break;
Andrew Morton1d372112005-06-21 17:16:42 -0700587 }
588 }
Andrew Mortonba40aaf2005-06-21 17:16:46 -0700589 ret = rock_continue(&rs);
590 if (ret == 0)
591 goto repeat;
592 if (ret == 1)
593 ret = 0;
Andrew Morton7fa393a2005-06-21 17:16:43 -0700594out:
Andrew Mortonba40aaf2005-06-21 17:16:46 -0700595 kfree(rs.buffer);
596 return ret;
Andrew Mortonf2966632005-06-21 17:16:51 -0700597eio:
598 ret = -EIO;
599 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700600}
601
602static char *get_symlink_chunk(char *rpnt, struct rock_ridge *rr, char *plimit)
603{
604 int slen;
605 int rootflag;
606 struct SL_component *oldslp;
607 struct SL_component *slp;
608 slen = rr->len - 5;
609 slp = &rr->u.SL.link;
610 while (slen > 1) {
611 rootflag = 0;
612 switch (slp->flags & ~1) {
613 case 0:
614 if (slp->len > plimit - rpnt)
615 return NULL;
616 memcpy(rpnt, slp->text, slp->len);
Andrew Morton1d372112005-06-21 17:16:42 -0700617 rpnt += slp->len;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700618 break;
619 case 2:
620 if (rpnt >= plimit)
621 return NULL;
Andrew Morton1d372112005-06-21 17:16:42 -0700622 *rpnt++ = '.';
Linus Torvalds1da177e2005-04-16 15:20:36 -0700623 break;
624 case 4:
625 if (2 > plimit - rpnt)
626 return NULL;
Andrew Morton1d372112005-06-21 17:16:42 -0700627 *rpnt++ = '.';
628 *rpnt++ = '.';
Linus Torvalds1da177e2005-04-16 15:20:36 -0700629 break;
630 case 8:
631 if (rpnt >= plimit)
632 return NULL;
633 rootflag = 1;
Andrew Morton1d372112005-06-21 17:16:42 -0700634 *rpnt++ = '/';
Linus Torvalds1da177e2005-04-16 15:20:36 -0700635 break;
636 default:
637 printk("Symlink component flag not implemented (%d)\n",
Andrew Morton1d372112005-06-21 17:16:42 -0700638 slp->flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700639 }
640 slen -= slp->len + 2;
641 oldslp = slp;
Andrew Morton1d372112005-06-21 17:16:42 -0700642 slp = (struct SL_component *)((char *)slp + slp->len + 2);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700643
644 if (slen < 2) {
645 /*
646 * If there is another SL record, and this component
647 * record isn't continued, then add a slash.
648 */
649 if ((!rootflag) && (rr->u.SL.flags & 1) &&
650 !(oldslp->flags & 1)) {
651 if (rpnt >= plimit)
652 return NULL;
Andrew Morton1d372112005-06-21 17:16:42 -0700653 *rpnt++ = '/';
Linus Torvalds1da177e2005-04-16 15:20:36 -0700654 }
655 break;
656 }
657
658 /*
659 * If this component record isn't continued, then append a '/'.
660 */
661 if (!rootflag && !(oldslp->flags & 1)) {
662 if (rpnt >= plimit)
663 return NULL;
Andrew Morton1d372112005-06-21 17:16:42 -0700664 *rpnt++ = '/';
Linus Torvalds1da177e2005-04-16 15:20:36 -0700665 }
666 }
667 return rpnt;
668}
669
Jan Kara410dd3c2014-08-17 11:49:57 +0200670int parse_rock_ridge_inode(struct iso_directory_record *de, struct inode *inode,
671 int relocated)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700672{
Jan Kara410dd3c2014-08-17 11:49:57 +0200673 int flags = relocated ? RR_RELOC_DE : 0;
674 int result = parse_rock_ridge_inode_internal(de, inode, flags);
Andrew Morton73739092005-06-21 17:16:47 -0700675
676 /*
677 * if rockridge flag was reset and we didn't look for attributes
678 * behind eventual XA attributes, have a look there
679 */
Andrew Morton1d372112005-06-21 17:16:42 -0700680 if ((ISOFS_SB(inode->i_sb)->s_rock_offset == -1)
681 && (ISOFS_SB(inode->i_sb)->s_rock == 2)) {
Jan Kara410dd3c2014-08-17 11:49:57 +0200682 result = parse_rock_ridge_inode_internal(de, inode,
683 flags | RR_REGARD_XA);
Andrew Morton1d372112005-06-21 17:16:42 -0700684 }
685 return result;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700686}
687
Andrew Morton73739092005-06-21 17:16:47 -0700688/*
689 * readpage() for symlinks: reads symlink contents into the page and either
690 * makes it uptodate and returns 0 or returns error (-EIO)
691 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700692static int rock_ridge_symlink_readpage(struct file *file, struct page *page)
693{
694 struct inode *inode = page->mapping->host;
Andrew Morton1d372112005-06-21 17:16:42 -0700695 struct iso_inode_info *ei = ISOFS_I(inode);
Arnd Bergmann4f819a72010-09-12 19:05:56 +0200696 struct isofs_sb_info *sbi = ISOFS_SB(inode->i_sb);
Al Viro21fc61c2015-11-17 01:07:57 -0500697 char *link = page_address(page);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700698 unsigned long bufsize = ISOFS_BUFFER_SIZE(inode);
699 struct buffer_head *bh;
700 char *rpnt = link;
701 unsigned char *pnt;
Andrew Morton76ab07e2005-06-21 17:16:46 -0700702 struct iso_directory_record *raw_de;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700703 unsigned long block, offset;
704 int sig;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700705 struct rock_ridge *rr;
Andrew Mortonba40aaf2005-06-21 17:16:46 -0700706 struct rock_state rs;
707 int ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700708
Arnd Bergmann4f819a72010-09-12 19:05:56 +0200709 if (!sbi->s_rock)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700710 goto error;
711
Andrew Mortonba40aaf2005-06-21 17:16:46 -0700712 init_rock_state(&rs, inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700713 block = ei->i_iget5_block;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700714 bh = sb_bread(inode->i_sb, block);
715 if (!bh)
716 goto out_noread;
717
Andrew Morton1d372112005-06-21 17:16:42 -0700718 offset = ei->i_iget5_offset;
719 pnt = (unsigned char *)bh->b_data + offset;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700720
Andrew Morton76ab07e2005-06-21 17:16:46 -0700721 raw_de = (struct iso_directory_record *)pnt;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700722
723 /*
724 * If we go past the end of the buffer, there is some sort of error.
725 */
726 if (offset + *pnt > bufsize)
727 goto out_bad_span;
728
Andrew Morton73739092005-06-21 17:16:47 -0700729 /*
730 * Now test for possible Rock Ridge extensions which will override
731 * some of these numbers in the inode structure.
732 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700733
Andrew Mortonba40aaf2005-06-21 17:16:46 -0700734 setup_rock_ridge(raw_de, inode, &rs);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700735
Andrew Morton7fa393a2005-06-21 17:16:43 -0700736repeat:
Andrew Mortonba40aaf2005-06-21 17:16:46 -0700737 while (rs.len > 2) { /* There may be one byte for padding somewhere */
738 rr = (struct rock_ridge *)rs.chr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700739 if (rr->len < 3)
740 goto out; /* Something got screwed up here */
Andrew Mortonba40aaf2005-06-21 17:16:46 -0700741 sig = isonum_721(rs.chr);
Andrew Mortonf2966632005-06-21 17:16:51 -0700742 if (rock_check_overflow(&rs, sig))
743 goto out;
Andrew Mortonba40aaf2005-06-21 17:16:46 -0700744 rs.chr += rr->len;
745 rs.len -= rr->len;
746 if (rs.len < 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700747 goto out; /* corrupted isofs */
748
749 switch (sig) {
750 case SIG('R', 'R'):
751 if ((rr->u.RR.flags[0] & RR_SL) == 0)
752 goto out;
753 break;
754 case SIG('S', 'P'):
Andrew Morton12121712005-06-21 17:16:44 -0700755 if (check_sp(rr, inode))
756 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700757 break;
758 case SIG('S', 'L'):
759 rpnt = get_symlink_chunk(rpnt, rr,
760 link + (PAGE_SIZE - 1));
761 if (rpnt == NULL)
762 goto out;
763 break;
764 case SIG('C', 'E'):
765 /* This tells is if there is a continuation record */
Andrew Mortonba40aaf2005-06-21 17:16:46 -0700766 rs.cont_extent = isonum_733(rr->u.CE.extent);
767 rs.cont_offset = isonum_733(rr->u.CE.offset);
768 rs.cont_size = isonum_733(rr->u.CE.size);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700769 default:
770 break;
771 }
772 }
Andrew Mortonba40aaf2005-06-21 17:16:46 -0700773 ret = rock_continue(&rs);
774 if (ret == 0)
775 goto repeat;
776 if (ret < 0)
777 goto fail;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700778
779 if (rpnt == link)
780 goto fail;
781 brelse(bh);
782 *rpnt = '\0';
Linus Torvalds1da177e2005-04-16 15:20:36 -0700783 SetPageUptodate(page);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700784 unlock_page(page);
785 return 0;
786
787 /* error exit from macro */
Andrew Morton7fa393a2005-06-21 17:16:43 -0700788out:
Andrew Mortonba40aaf2005-06-21 17:16:46 -0700789 kfree(rs.buffer);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700790 goto fail;
Andrew Morton7fa393a2005-06-21 17:16:43 -0700791out_noread:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700792 printk("unable to read i-node block");
793 goto fail;
Andrew Morton7fa393a2005-06-21 17:16:43 -0700794out_bad_span:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700795 printk("symlink spans iso9660 blocks\n");
Andrew Morton7fa393a2005-06-21 17:16:43 -0700796fail:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700797 brelse(bh);
Andrew Morton7fa393a2005-06-21 17:16:43 -0700798error:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700799 SetPageError(page);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700800 unlock_page(page);
801 return -EIO;
802}
803
Christoph Hellwigf5e54d62006-06-28 04:26:44 -0700804const struct address_space_operations isofs_symlink_aops = {
Andrew Morton1d372112005-06-21 17:16:42 -0700805 .readpage = rock_ridge_symlink_readpage
Linus Torvalds1da177e2005-04-16 15:20:36 -0700806};