nfs: Check whether a layout pointer is NULL before free it
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / fs / nfs / mount_clnt.c
CommitLineData
1da177e4 1/*
19207231 2 * In-kernel MOUNT protocol client
1da177e4
LT
3 *
4 * Copyright (C) 1997, Olaf Kirch <okir@monad.swb.de>
5 */
6
7#include <linux/types.h>
8#include <linux/socket.h>
9#include <linux/kernel.h>
10#include <linux/errno.h>
11#include <linux/uio.h>
12#include <linux/net.h>
13#include <linux/in.h>
14#include <linux/sunrpc/clnt.h>
1da177e4
LT
15#include <linux/sunrpc/sched.h>
16#include <linux/nfs_fs.h>
8491945f 17#include "internal.h"
1da177e4 18
e27d359e 19#ifdef NFS_DEBUG
3ea97309 20# define NFSDBG_FACILITY NFSDBG_MOUNT
1da177e4
LT
21#endif
22
29a1bd6b
CL
23/*
24 * Defined by RFC 1094, section A.3; and RFC 1813, section 5.1.4
25 */
26#define MNTPATHLEN (1024)
27
28/*
29 * XDR data type sizes
30 */
31#define encode_dirpath_sz (1 + XDR_QUADLEN(MNTPATHLEN))
fb125295
CL
32#define MNT_status_sz (1)
33#define MNT_fhs_status_sz (1)
4fdcd996
CL
34#define MNT_fhandle_sz XDR_QUADLEN(NFS2_FHSIZE)
35#define MNT_fhandle3_sz (1 + XDR_QUADLEN(NFS3_FHSIZE))
a14017db 36#define MNT_authflav3_sz (1 + NFS_MAX_SECFLAVORS)
29a1bd6b
CL
37
38/*
39 * XDR argument and result sizes
40 */
41#define MNT_enc_dirpath_sz encode_dirpath_sz
8e02f6b9
CL
42#define MNT_dec_mountres_sz (MNT_status_sz + MNT_fhandle_sz)
43#define MNT_dec_mountres3_sz (MNT_status_sz + MNT_fhandle_sz + \
44 MNT_authflav3_sz)
29a1bd6b 45
2ad78097
CL
46/*
47 * Defined by RFC 1094, section A.5
48 */
49enum {
50 MOUNTPROC_NULL = 0,
51 MOUNTPROC_MNT = 1,
52 MOUNTPROC_DUMP = 2,
53 MOUNTPROC_UMNT = 3,
54 MOUNTPROC_UMNTALL = 4,
55 MOUNTPROC_EXPORT = 5,
56};
57
58/*
59 * Defined by RFC 1813, section 5.2
60 */
61enum {
62 MOUNTPROC3_NULL = 0,
63 MOUNTPROC3_MNT = 1,
64 MOUNTPROC3_DUMP = 2,
65 MOUNTPROC3_UMNT = 3,
66 MOUNTPROC3_UMNTALL = 4,
67 MOUNTPROC3_EXPORT = 5,
68};
69
a613fa16 70static const struct rpc_program mnt_program;
1da177e4 71
fb125295
CL
72/*
73 * Defined by OpenGroup XNFS Version 3W, chapter 8
74 */
75enum mountstat {
76 MNT_OK = 0,
77 MNT_EPERM = 1,
78 MNT_ENOENT = 2,
79 MNT_EACCES = 13,
80 MNT_EINVAL = 22,
81};
82
83static struct {
84 u32 status;
85 int errno;
86} mnt_errtbl[] = {
87 { .status = MNT_OK, .errno = 0, },
88 { .status = MNT_EPERM, .errno = -EPERM, },
89 { .status = MNT_ENOENT, .errno = -ENOENT, },
90 { .status = MNT_EACCES, .errno = -EACCES, },
91 { .status = MNT_EINVAL, .errno = -EINVAL, },
92};
93
94/*
95 * Defined by RFC 1813, section 5.1.5
96 */
97enum mountstat3 {
98 MNT3_OK = 0, /* no error */
99 MNT3ERR_PERM = 1, /* Not owner */
100 MNT3ERR_NOENT = 2, /* No such file or directory */
101 MNT3ERR_IO = 5, /* I/O error */
102 MNT3ERR_ACCES = 13, /* Permission denied */
103 MNT3ERR_NOTDIR = 20, /* Not a directory */
104 MNT3ERR_INVAL = 22, /* Invalid argument */
105 MNT3ERR_NAMETOOLONG = 63, /* Filename too long */
106 MNT3ERR_NOTSUPP = 10004, /* Operation not supported */
107 MNT3ERR_SERVERFAULT = 10006, /* A failure on the server */
108};
109
110static struct {
111 u32 status;
112 int errno;
113} mnt3_errtbl[] = {
114 { .status = MNT3_OK, .errno = 0, },
115 { .status = MNT3ERR_PERM, .errno = -EPERM, },
116 { .status = MNT3ERR_NOENT, .errno = -ENOENT, },
117 { .status = MNT3ERR_IO, .errno = -EIO, },
118 { .status = MNT3ERR_ACCES, .errno = -EACCES, },
119 { .status = MNT3ERR_NOTDIR, .errno = -ENOTDIR, },
120 { .status = MNT3ERR_INVAL, .errno = -EINVAL, },
121 { .status = MNT3ERR_NAMETOOLONG, .errno = -ENAMETOOLONG, },
122 { .status = MNT3ERR_NOTSUPP, .errno = -ENOTSUPP, },
fdcb4577 123 { .status = MNT3ERR_SERVERFAULT, .errno = -EREMOTEIO, },
fb125295
CL
124};
125
126struct mountres {
127 int errno;
128 struct nfs_fh *fh;
a14017db
CL
129 unsigned int *auth_count;
130 rpc_authflavor_t *auth_flavors;
fb125295
CL
131};
132
1da177e4 133struct mnt_fhstatus {
19207231
CL
134 u32 status;
135 struct nfs_fh *fh;
1da177e4
LT
136};
137
3ea97309
CL
138/**
139 * nfs_mount - Obtain an NFS file handle for the given host and path
c5d120f8 140 * @info: pointer to mount request arguments
3ea97309
CL
141 *
142 * Uses default timeout parameters specified by underlying transport.
1da177e4 143 */
c5d120f8 144int nfs_mount(struct nfs_mount_request *info)
1da177e4 145{
8e02f6b9
CL
146 struct mountres result = {
147 .fh = info->fh,
148 .auth_count = info->auth_flav_len,
149 .auth_flavors = info->auth_flavs,
1da177e4 150 };
dead28da 151 struct rpc_message msg = {
c5d120f8 152 .rpc_argp = info->dirpath,
dead28da
CL
153 .rpc_resp = &result,
154 };
3ea97309 155 struct rpc_create_args args = {
6d59b8d5 156 .net = info->net,
c5d120f8
CL
157 .protocol = info->protocol,
158 .address = info->sap,
159 .addrsize = info->salen,
160 .servername = info->hostname,
3ea97309 161 .program = &mnt_program,
c5d120f8 162 .version = info->version,
3ea97309 163 .authflavor = RPC_AUTH_UNIX,
3ea97309
CL
164 };
165 struct rpc_clnt *mnt_clnt;
1da177e4 166 int status;
1da177e4 167
3ea97309 168 dprintk("NFS: sending MNT request for %s:%s\n",
c5d120f8
CL
169 (info->hostname ? info->hostname : "server"),
170 info->dirpath);
1da177e4 171
50a737f8
CL
172 if (info->noresvport)
173 args.flags |= RPC_CLNT_CREATE_NONPRIVPORT;
174
3ea97309 175 mnt_clnt = rpc_create(&args);
1da177e4 176 if (IS_ERR(mnt_clnt))
013a8c1a 177 goto out_clnt_err;
1da177e4 178
c5d120f8 179 if (info->version == NFS_MNT3_VERSION)
dead28da
CL
180 msg.rpc_proc = &mnt_clnt->cl_procinfo[MOUNTPROC3_MNT];
181 else
2ad78097 182 msg.rpc_proc = &mnt_clnt->cl_procinfo[MOUNTPROC_MNT];
dead28da
CL
183
184 status = rpc_call_sync(mnt_clnt, &msg, 0);
90c5755f 185 rpc_shutdown_client(mnt_clnt);
013a8c1a
CL
186
187 if (status < 0)
188 goto out_call_err;
8e02f6b9 189 if (result.errno != 0)
013a8c1a
CL
190 goto out_mnt_err;
191
192 dprintk("NFS: MNT request succeeded\n");
193 status = 0;
194
195out:
196 return status;
197
198out_clnt_err:
199 status = PTR_ERR(mnt_clnt);
8e02f6b9 200 dprintk("NFS: failed to create MNT RPC client, status=%d\n", status);
013a8c1a
CL
201 goto out;
202
203out_call_err:
8e02f6b9 204 dprintk("NFS: MNT request failed, status=%d\n", status);
013a8c1a
CL
205 goto out;
206
207out_mnt_err:
8e02f6b9
CL
208 dprintk("NFS: MNT server returned result %d\n", result.errno);
209 status = result.errno;
013a8c1a 210 goto out;
1da177e4
LT
211}
212
0b524123
CL
213/**
214 * nfs_umount - Notify a server that we have unmounted this export
215 * @info: pointer to umount request arguments
216 *
217 * MOUNTPROC_UMNT is advisory, so we set a short timeout, and always
218 * use UDP.
219 */
220void nfs_umount(const struct nfs_mount_request *info)
221{
222 static const struct rpc_timeout nfs_umnt_timeout = {
223 .to_initval = 1 * HZ,
224 .to_maxval = 3 * HZ,
225 .to_retries = 2,
226 };
227 struct rpc_create_args args = {
6d59b8d5 228 .net = info->net,
0b524123
CL
229 .protocol = IPPROTO_UDP,
230 .address = info->sap,
231 .addrsize = info->salen,
232 .timeout = &nfs_umnt_timeout,
233 .servername = info->hostname,
234 .program = &mnt_program,
235 .version = info->version,
236 .authflavor = RPC_AUTH_UNIX,
237 .flags = RPC_CLNT_CREATE_NOPING,
238 };
0b524123
CL
239 struct rpc_message msg = {
240 .rpc_argp = info->dirpath,
0b524123
CL
241 };
242 struct rpc_clnt *clnt;
243 int status;
244
245 if (info->noresvport)
246 args.flags |= RPC_CLNT_CREATE_NONPRIVPORT;
247
248 clnt = rpc_create(&args);
c8b031eb 249 if (IS_ERR(clnt))
0b524123
CL
250 goto out_clnt_err;
251
252 dprintk("NFS: sending UMNT request for %s:%s\n",
253 (info->hostname ? info->hostname : "server"), info->dirpath);
254
255 if (info->version == NFS_MNT3_VERSION)
256 msg.rpc_proc = &clnt->cl_procinfo[MOUNTPROC3_UMNT];
257 else
258 msg.rpc_proc = &clnt->cl_procinfo[MOUNTPROC_UMNT];
259
260 status = rpc_call_sync(clnt, &msg, 0);
261 rpc_shutdown_client(clnt);
262
263 if (unlikely(status < 0))
264 goto out_call_err;
265
266 return;
267
268out_clnt_err:
269 dprintk("NFS: failed to create UMNT RPC client, status=%ld\n",
270 PTR_ERR(clnt));
271 return;
272
273out_call_err:
274 dprintk("NFS: UMNT request failed, status=%d\n", status);
275}
276
1da177e4
LT
277/*
278 * XDR encode/decode functions for MOUNT
279 */
1da177e4 280
98eb2b4f 281static void encode_mntdirpath(struct xdr_stream *xdr, const char *pathname)
29a1bd6b
CL
282{
283 const u32 pathname_len = strlen(pathname);
284 __be32 *p;
285
98eb2b4f
CL
286 BUG_ON(pathname_len > MNTPATHLEN);
287 p = xdr_reserve_space(xdr, 4 + pathname_len);
29a1bd6b 288 xdr_encode_opaque(p, pathname, pathname_len);
29a1bd6b
CL
289}
290
9f06c719
CL
291static void mnt_xdr_enc_dirpath(struct rpc_rqst *req, struct xdr_stream *xdr,
292 const char *dirpath)
29a1bd6b 293{
9f06c719 294 encode_mntdirpath(xdr, dirpath);
29a1bd6b
CL
295}
296
fb125295
CL
297/*
298 * RFC 1094: "A non-zero status indicates some sort of error. In this
299 * case, the status is a UNIX error number." This can be problematic
300 * if the server and client use different errno values for the same
301 * error.
302 *
303 * However, the OpenGroup XNFS spec provides a simple mapping that is
304 * independent of local errno values on the server and the client.
305 */
306static int decode_status(struct xdr_stream *xdr, struct mountres *res)
307{
308 unsigned int i;
309 u32 status;
310 __be32 *p;
311
98eb2b4f 312 p = xdr_inline_decode(xdr, 4);
fb125295
CL
313 if (unlikely(p == NULL))
314 return -EIO;
98eb2b4f 315 status = be32_to_cpup(p);
fb125295 316
dd8ac1da 317 for (i = 0; i < ARRAY_SIZE(mnt_errtbl); i++) {
fb125295
CL
318 if (mnt_errtbl[i].status == status) {
319 res->errno = mnt_errtbl[i].errno;
320 return 0;
321 }
322 }
323
324 dprintk("NFS: unrecognized MNT status code: %u\n", status);
325 res->errno = -EACCES;
326 return 0;
327}
328
4fdcd996
CL
329static int decode_fhandle(struct xdr_stream *xdr, struct mountres *res)
330{
331 struct nfs_fh *fh = res->fh;
332 __be32 *p;
333
334 p = xdr_inline_decode(xdr, NFS2_FHSIZE);
335 if (unlikely(p == NULL))
336 return -EIO;
337
338 fh->size = NFS2_FHSIZE;
339 memcpy(fh->data, p, NFS2_FHSIZE);
340 return 0;
341}
342
bf269551
CL
343static int mnt_xdr_dec_mountres(struct rpc_rqst *req,
344 struct xdr_stream *xdr,
345 struct mountres *res)
8e02f6b9 346{
8e02f6b9
CL
347 int status;
348
bf269551 349 status = decode_status(xdr, res);
8e02f6b9
CL
350 if (unlikely(status != 0 || res->errno != 0))
351 return status;
bf269551 352 return decode_fhandle(xdr, res);
8e02f6b9
CL
353}
354
fb125295
CL
355static int decode_fhs_status(struct xdr_stream *xdr, struct mountres *res)
356{
357 unsigned int i;
358 u32 status;
359 __be32 *p;
360
98eb2b4f 361 p = xdr_inline_decode(xdr, 4);
fb125295
CL
362 if (unlikely(p == NULL))
363 return -EIO;
98eb2b4f 364 status = be32_to_cpup(p);
fb125295 365
dd8ac1da 366 for (i = 0; i < ARRAY_SIZE(mnt3_errtbl); i++) {
fb125295
CL
367 if (mnt3_errtbl[i].status == status) {
368 res->errno = mnt3_errtbl[i].errno;
369 return 0;
370 }
371 }
372
373 dprintk("NFS: unrecognized MNT3 status code: %u\n", status);
374 res->errno = -EACCES;
375 return 0;
376}
377
4fdcd996
CL
378static int decode_fhandle3(struct xdr_stream *xdr, struct mountres *res)
379{
380 struct nfs_fh *fh = res->fh;
381 u32 size;
382 __be32 *p;
383
98eb2b4f 384 p = xdr_inline_decode(xdr, 4);
4fdcd996
CL
385 if (unlikely(p == NULL))
386 return -EIO;
387
98eb2b4f 388 size = be32_to_cpup(p);
4fdcd996
CL
389 if (size > NFS3_FHSIZE || size == 0)
390 return -EIO;
391
392 p = xdr_inline_decode(xdr, size);
393 if (unlikely(p == NULL))
394 return -EIO;
395
396 fh->size = size;
397 memcpy(fh->data, p, size);
398 return 0;
399}
400
a14017db
CL
401static int decode_auth_flavors(struct xdr_stream *xdr, struct mountres *res)
402{
403 rpc_authflavor_t *flavors = res->auth_flavors;
404 unsigned int *count = res->auth_count;
405 u32 entries, i;
406 __be32 *p;
407
408 if (*count == 0)
409 return 0;
410
98eb2b4f 411 p = xdr_inline_decode(xdr, 4);
a14017db
CL
412 if (unlikely(p == NULL))
413 return -EIO;
98eb2b4f 414 entries = be32_to_cpup(p);
a14017db
CL
415 dprintk("NFS: received %u auth flavors\n", entries);
416 if (entries > NFS_MAX_SECFLAVORS)
417 entries = NFS_MAX_SECFLAVORS;
418
98eb2b4f 419 p = xdr_inline_decode(xdr, 4 * entries);
a14017db
CL
420 if (unlikely(p == NULL))
421 return -EIO;
422
423 if (entries > *count)
424 entries = *count;
425
426 for (i = 0; i < entries; i++) {
98eb2b4f 427 flavors[i] = be32_to_cpup(p++);
ed58b291 428 dprintk("NFS: auth flavor[%u]: %d\n", i, flavors[i]);
a14017db
CL
429 }
430 *count = i;
431
432 return 0;
433}
434
bf269551
CL
435static int mnt_xdr_dec_mountres3(struct rpc_rqst *req,
436 struct xdr_stream *xdr,
437 struct mountres *res)
8e02f6b9 438{
8e02f6b9
CL
439 int status;
440
bf269551 441 status = decode_fhs_status(xdr, res);
8e02f6b9
CL
442 if (unlikely(status != 0 || res->errno != 0))
443 return status;
bf269551 444 status = decode_fhandle3(xdr, res);
8e02f6b9
CL
445 if (unlikely(status != 0)) {
446 res->errno = -EBADHANDLE;
447 return 0;
448 }
bf269551 449 return decode_auth_flavors(xdr, res);
8e02f6b9
CL
450}
451
19207231 452static struct rpc_procinfo mnt_procedures[] = {
2ad78097
CL
453 [MOUNTPROC_MNT] = {
454 .p_proc = MOUNTPROC_MNT,
9f06c719 455 .p_encode = (kxdreproc_t)mnt_xdr_enc_dirpath,
bf269551 456 .p_decode = (kxdrdproc_t)mnt_xdr_dec_mountres,
29a1bd6b 457 .p_arglen = MNT_enc_dirpath_sz,
8e02f6b9 458 .p_replen = MNT_dec_mountres_sz,
2ad78097 459 .p_statidx = MOUNTPROC_MNT,
19207231 460 .p_name = "MOUNT",
1da177e4 461 },
0b524123
CL
462 [MOUNTPROC_UMNT] = {
463 .p_proc = MOUNTPROC_UMNT,
9f06c719 464 .p_encode = (kxdreproc_t)mnt_xdr_enc_dirpath,
0b524123
CL
465 .p_arglen = MNT_enc_dirpath_sz,
466 .p_statidx = MOUNTPROC_UMNT,
467 .p_name = "UMOUNT",
468 },
1da177e4
LT
469};
470
471static struct rpc_procinfo mnt3_procedures[] = {
19207231
CL
472 [MOUNTPROC3_MNT] = {
473 .p_proc = MOUNTPROC3_MNT,
9f06c719 474 .p_encode = (kxdreproc_t)mnt_xdr_enc_dirpath,
bf269551 475 .p_decode = (kxdrdproc_t)mnt_xdr_dec_mountres3,
29a1bd6b 476 .p_arglen = MNT_enc_dirpath_sz,
8e02f6b9 477 .p_replen = MNT_dec_mountres3_sz,
19207231
CL
478 .p_statidx = MOUNTPROC3_MNT,
479 .p_name = "MOUNT",
1da177e4 480 },
0b524123
CL
481 [MOUNTPROC3_UMNT] = {
482 .p_proc = MOUNTPROC3_UMNT,
9f06c719 483 .p_encode = (kxdreproc_t)mnt_xdr_enc_dirpath,
0b524123
CL
484 .p_arglen = MNT_enc_dirpath_sz,
485 .p_statidx = MOUNTPROC3_UMNT,
486 .p_name = "UMOUNT",
487 },
1da177e4
LT
488};
489
490
a613fa16 491static const struct rpc_version mnt_version1 = {
19207231 492 .number = 1,
5b362ac3 493 .nrprocs = ARRAY_SIZE(mnt_procedures),
19207231 494 .procs = mnt_procedures,
1da177e4
LT
495};
496
a613fa16 497static const struct rpc_version mnt_version3 = {
19207231 498 .number = 3,
5b362ac3 499 .nrprocs = ARRAY_SIZE(mnt3_procedures),
19207231 500 .procs = mnt3_procedures,
1da177e4
LT
501};
502
a613fa16 503static const struct rpc_version *mnt_version[] = {
1da177e4
LT
504 NULL,
505 &mnt_version1,
506 NULL,
507 &mnt_version3,
508};
509
19207231 510static struct rpc_stat mnt_stats;
1da177e4 511
a613fa16 512static const struct rpc_program mnt_program = {
1da177e4
LT
513 .name = "mount",
514 .number = NFS_MNT_PROGRAM,
e8c96f8c 515 .nrvers = ARRAY_SIZE(mnt_version),
1da177e4
LT
516 .version = mnt_version,
517 .stats = &mnt_stats,
518};