Merge tag 'devicetree-fixes-for-6.8-2' of git://git.kernel.org/pub/scm/linux/kernel...
[linux-2.6-block.git] / fs / nfs / callback_xdr.c
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * linux/fs/nfs/callback_xdr.c
4  *
5  * Copyright (C) 2004 Trond Myklebust
6  *
7  * NFSv4 callback encode/decode procedures
8  */
9 #include <linux/kernel.h>
10 #include <linux/sunrpc/svc.h>
11 #include <linux/nfs4.h>
12 #include <linux/nfs_fs.h>
13 #include <linux/ratelimit.h>
14 #include <linux/printk.h>
15 #include <linux/slab.h>
16 #include <linux/sunrpc/bc_xprt.h>
17 #include "nfs4_fs.h"
18 #include "callback.h"
19 #include "internal.h"
20 #include "nfs4session.h"
21 #include "nfs4trace.h"
22
23 #define CB_OP_TAGLEN_MAXSZ              (512)
24 #define CB_OP_HDR_RES_MAXSZ             (2 * 4) // opcode, status
25 #define CB_OP_GETATTR_BITMAP_MAXSZ      (4 * 4) // bitmap length, 3 bitmaps
26 #define CB_OP_GETATTR_RES_MAXSZ         (CB_OP_HDR_RES_MAXSZ + \
27                                          CB_OP_GETATTR_BITMAP_MAXSZ + \
28                                          /* change, size, ctime, mtime */\
29                                          (2 + 2 + 3 + 3) * 4)
30 #define CB_OP_RECALL_RES_MAXSZ          (CB_OP_HDR_RES_MAXSZ)
31
32 #if defined(CONFIG_NFS_V4_1)
33 #define CB_OP_LAYOUTRECALL_RES_MAXSZ    (CB_OP_HDR_RES_MAXSZ)
34 #define CB_OP_DEVICENOTIFY_RES_MAXSZ    (CB_OP_HDR_RES_MAXSZ)
35 #define CB_OP_SEQUENCE_RES_MAXSZ        (CB_OP_HDR_RES_MAXSZ + \
36                                          NFS4_MAX_SESSIONID_LEN + \
37                                          (1 + 3) * 4) // seqid, 3 slotids
38 #define CB_OP_RECALLANY_RES_MAXSZ       (CB_OP_HDR_RES_MAXSZ)
39 #define CB_OP_RECALLSLOT_RES_MAXSZ      (CB_OP_HDR_RES_MAXSZ)
40 #define CB_OP_NOTIFY_LOCK_RES_MAXSZ     (CB_OP_HDR_RES_MAXSZ)
41 #endif /* CONFIG_NFS_V4_1 */
42 #ifdef CONFIG_NFS_V4_2
43 #define CB_OP_OFFLOAD_RES_MAXSZ         (CB_OP_HDR_RES_MAXSZ)
44 #endif /* CONFIG_NFS_V4_2 */
45
46 #define NFSDBG_FACILITY NFSDBG_CALLBACK
47
48 /* Internal error code */
49 #define NFS4ERR_RESOURCE_HDR    11050
50
51 struct callback_op {
52         __be32 (*process_op)(void *, void *, struct cb_process_state *);
53         __be32 (*decode_args)(struct svc_rqst *, struct xdr_stream *, void *);
54         __be32 (*encode_res)(struct svc_rqst *, struct xdr_stream *,
55                         const void *);
56         long res_maxsize;
57 };
58
59 static struct callback_op callback_ops[];
60
61 static __be32 nfs4_callback_null(struct svc_rqst *rqstp)
62 {
63         return htonl(NFS4_OK);
64 }
65
66 /*
67  * svc_process_common() looks for an XDR encoder to know when
68  * not to drop a Reply.
69  */
70 static bool nfs4_encode_void(struct svc_rqst *rqstp, struct xdr_stream *xdr)
71 {
72         return true;
73 }
74
75 static __be32 decode_string(struct xdr_stream *xdr, unsigned int *len,
76                 const char **str, size_t maxlen)
77 {
78         ssize_t err;
79
80         err = xdr_stream_decode_opaque_inline(xdr, (void **)str, maxlen);
81         if (err < 0)
82                 return cpu_to_be32(NFS4ERR_RESOURCE);
83         *len = err;
84         return 0;
85 }
86
87 static __be32 decode_fh(struct xdr_stream *xdr, struct nfs_fh *fh)
88 {
89         __be32 *p;
90
91         p = xdr_inline_decode(xdr, 4);
92         if (unlikely(p == NULL))
93                 return htonl(NFS4ERR_RESOURCE);
94         fh->size = ntohl(*p);
95         if (fh->size > NFS4_FHSIZE)
96                 return htonl(NFS4ERR_BADHANDLE);
97         p = xdr_inline_decode(xdr, fh->size);
98         if (unlikely(p == NULL))
99                 return htonl(NFS4ERR_RESOURCE);
100         memcpy(&fh->data[0], p, fh->size);
101         memset(&fh->data[fh->size], 0, sizeof(fh->data) - fh->size);
102         return 0;
103 }
104
105 static __be32 decode_bitmap(struct xdr_stream *xdr, uint32_t *bitmap)
106 {
107         __be32 *p;
108         unsigned int attrlen;
109
110         p = xdr_inline_decode(xdr, 4);
111         if (unlikely(p == NULL))
112                 return htonl(NFS4ERR_RESOURCE);
113         attrlen = ntohl(*p);
114         p = xdr_inline_decode(xdr, attrlen << 2);
115         if (unlikely(p == NULL))
116                 return htonl(NFS4ERR_RESOURCE);
117         if (likely(attrlen > 0))
118                 bitmap[0] = ntohl(*p++);
119         if (attrlen > 1)
120                 bitmap[1] = ntohl(*p);
121         return 0;
122 }
123
124 static __be32 decode_stateid(struct xdr_stream *xdr, nfs4_stateid *stateid)
125 {
126         __be32 *p;
127
128         p = xdr_inline_decode(xdr, NFS4_STATEID_SIZE);
129         if (unlikely(p == NULL))
130                 return htonl(NFS4ERR_RESOURCE);
131         memcpy(stateid->data, p, NFS4_STATEID_SIZE);
132         return 0;
133 }
134
135 static __be32 decode_delegation_stateid(struct xdr_stream *xdr, nfs4_stateid *stateid)
136 {
137         stateid->type = NFS4_DELEGATION_STATEID_TYPE;
138         return decode_stateid(xdr, stateid);
139 }
140
141 static __be32 decode_compound_hdr_arg(struct xdr_stream *xdr, struct cb_compound_hdr_arg *hdr)
142 {
143         __be32 *p;
144         __be32 status;
145
146         status = decode_string(xdr, &hdr->taglen, &hdr->tag, CB_OP_TAGLEN_MAXSZ);
147         if (unlikely(status != 0))
148                 return status;
149         p = xdr_inline_decode(xdr, 12);
150         if (unlikely(p == NULL))
151                 return htonl(NFS4ERR_RESOURCE);
152         hdr->minorversion = ntohl(*p++);
153         /* Check for minor version support */
154         if (hdr->minorversion <= NFS4_MAX_MINOR_VERSION) {
155                 hdr->cb_ident = ntohl(*p++); /* ignored by v4.1 and v4.2 */
156         } else {
157                 pr_warn_ratelimited("NFS: %s: NFSv4 server callback with "
158                         "illegal minor version %u!\n",
159                         __func__, hdr->minorversion);
160                 return htonl(NFS4ERR_MINOR_VERS_MISMATCH);
161         }
162         hdr->nops = ntohl(*p);
163         return 0;
164 }
165
166 static __be32 decode_op_hdr(struct xdr_stream *xdr, unsigned int *op)
167 {
168         __be32 *p;
169         p = xdr_inline_decode(xdr, 4);
170         if (unlikely(p == NULL))
171                 return htonl(NFS4ERR_RESOURCE_HDR);
172         *op = ntohl(*p);
173         return 0;
174 }
175
176 static __be32 decode_getattr_args(struct svc_rqst *rqstp,
177                 struct xdr_stream *xdr, void *argp)
178 {
179         struct cb_getattrargs *args = argp;
180         __be32 status;
181
182         status = decode_fh(xdr, &args->fh);
183         if (unlikely(status != 0))
184                 return status;
185         return decode_bitmap(xdr, args->bitmap);
186 }
187
188 static __be32 decode_recall_args(struct svc_rqst *rqstp,
189                 struct xdr_stream *xdr, void *argp)
190 {
191         struct cb_recallargs *args = argp;
192         __be32 *p;
193         __be32 status;
194
195         status = decode_delegation_stateid(xdr, &args->stateid);
196         if (unlikely(status != 0))
197                 return status;
198         p = xdr_inline_decode(xdr, 4);
199         if (unlikely(p == NULL))
200                 return htonl(NFS4ERR_RESOURCE);
201         args->truncate = ntohl(*p);
202         return decode_fh(xdr, &args->fh);
203 }
204
205 #if defined(CONFIG_NFS_V4_1)
206 static __be32 decode_layout_stateid(struct xdr_stream *xdr, nfs4_stateid *stateid)
207 {
208         stateid->type = NFS4_LAYOUT_STATEID_TYPE;
209         return decode_stateid(xdr, stateid);
210 }
211
212 static __be32 decode_layoutrecall_args(struct svc_rqst *rqstp,
213                                        struct xdr_stream *xdr, void *argp)
214 {
215         struct cb_layoutrecallargs *args = argp;
216         __be32 *p;
217         __be32 status = 0;
218         uint32_t iomode;
219
220         p = xdr_inline_decode(xdr, 4 * sizeof(uint32_t));
221         if (unlikely(p == NULL))
222                 return htonl(NFS4ERR_BADXDR);
223
224         args->cbl_layout_type = ntohl(*p++);
225         /* Depite the spec's xdr, iomode really belongs in the FILE switch,
226          * as it is unusable and ignored with the other types.
227          */
228         iomode = ntohl(*p++);
229         args->cbl_layoutchanged = ntohl(*p++);
230         args->cbl_recall_type = ntohl(*p++);
231
232         if (args->cbl_recall_type == RETURN_FILE) {
233                 args->cbl_range.iomode = iomode;
234                 status = decode_fh(xdr, &args->cbl_fh);
235                 if (unlikely(status != 0))
236                         return status;
237
238                 p = xdr_inline_decode(xdr, 2 * sizeof(uint64_t));
239                 if (unlikely(p == NULL))
240                         return htonl(NFS4ERR_BADXDR);
241                 p = xdr_decode_hyper(p, &args->cbl_range.offset);
242                 p = xdr_decode_hyper(p, &args->cbl_range.length);
243                 return decode_layout_stateid(xdr, &args->cbl_stateid);
244         } else if (args->cbl_recall_type == RETURN_FSID) {
245                 p = xdr_inline_decode(xdr, 2 * sizeof(uint64_t));
246                 if (unlikely(p == NULL))
247                         return htonl(NFS4ERR_BADXDR);
248                 p = xdr_decode_hyper(p, &args->cbl_fsid.major);
249                 p = xdr_decode_hyper(p, &args->cbl_fsid.minor);
250         } else if (args->cbl_recall_type != RETURN_ALL)
251                 return htonl(NFS4ERR_BADXDR);
252         return 0;
253 }
254
255 static
256 __be32 decode_devicenotify_args(struct svc_rqst *rqstp,
257                                 struct xdr_stream *xdr,
258                                 void *argp)
259 {
260         struct cb_devicenotifyargs *args = argp;
261         uint32_t tmp, n, i;
262         __be32 *p;
263         __be32 status = 0;
264
265         /* Num of device notifications */
266         p = xdr_inline_decode(xdr, sizeof(uint32_t));
267         if (unlikely(p == NULL)) {
268                 status = htonl(NFS4ERR_BADXDR);
269                 goto out;
270         }
271         n = ntohl(*p++);
272         if (n == 0)
273                 goto out;
274
275         args->devs = kmalloc_array(n, sizeof(*args->devs), GFP_KERNEL);
276         if (!args->devs) {
277                 status = htonl(NFS4ERR_DELAY);
278                 goto out;
279         }
280
281         /* Decode each dev notification */
282         for (i = 0; i < n; i++) {
283                 struct cb_devicenotifyitem *dev = &args->devs[i];
284
285                 p = xdr_inline_decode(xdr, (4 * sizeof(uint32_t)) +
286                                       NFS4_DEVICEID4_SIZE);
287                 if (unlikely(p == NULL)) {
288                         status = htonl(NFS4ERR_BADXDR);
289                         goto err;
290                 }
291
292                 tmp = ntohl(*p++);      /* bitmap size */
293                 if (tmp != 1) {
294                         status = htonl(NFS4ERR_INVAL);
295                         goto err;
296                 }
297                 dev->cbd_notify_type = ntohl(*p++);
298                 if (dev->cbd_notify_type != NOTIFY_DEVICEID4_CHANGE &&
299                     dev->cbd_notify_type != NOTIFY_DEVICEID4_DELETE) {
300                         status = htonl(NFS4ERR_INVAL);
301                         goto err;
302                 }
303
304                 tmp = ntohl(*p++);      /* opaque size */
305                 if (((dev->cbd_notify_type == NOTIFY_DEVICEID4_CHANGE) &&
306                      (tmp != NFS4_DEVICEID4_SIZE + 8)) ||
307                     ((dev->cbd_notify_type == NOTIFY_DEVICEID4_DELETE) &&
308                      (tmp != NFS4_DEVICEID4_SIZE + 4))) {
309                         status = htonl(NFS4ERR_INVAL);
310                         goto err;
311                 }
312                 dev->cbd_layout_type = ntohl(*p++);
313                 memcpy(dev->cbd_dev_id.data, p, NFS4_DEVICEID4_SIZE);
314                 p += XDR_QUADLEN(NFS4_DEVICEID4_SIZE);
315
316                 if (dev->cbd_layout_type == NOTIFY_DEVICEID4_CHANGE) {
317                         p = xdr_inline_decode(xdr, sizeof(uint32_t));
318                         if (unlikely(p == NULL)) {
319                                 status = htonl(NFS4ERR_BADXDR);
320                                 goto err;
321                         }
322                         dev->cbd_immediate = ntohl(*p++);
323                 } else {
324                         dev->cbd_immediate = 0;
325                 }
326
327                 dprintk("%s: type %d layout 0x%x immediate %d\n",
328                         __func__, dev->cbd_notify_type, dev->cbd_layout_type,
329                         dev->cbd_immediate);
330         }
331         args->ndevs = n;
332         dprintk("%s: ndevs %d\n", __func__, args->ndevs);
333         return 0;
334 err:
335         kfree(args->devs);
336 out:
337         args->devs = NULL;
338         args->ndevs = 0;
339         dprintk("%s: status %d ndevs %d\n",
340                 __func__, ntohl(status), args->ndevs);
341         return status;
342 }
343
344 static __be32 decode_sessionid(struct xdr_stream *xdr,
345                                  struct nfs4_sessionid *sid)
346 {
347         __be32 *p;
348
349         p = xdr_inline_decode(xdr, NFS4_MAX_SESSIONID_LEN);
350         if (unlikely(p == NULL))
351                 return htonl(NFS4ERR_RESOURCE);
352
353         memcpy(sid->data, p, NFS4_MAX_SESSIONID_LEN);
354         return 0;
355 }
356
357 static __be32 decode_rc_list(struct xdr_stream *xdr,
358                                struct referring_call_list *rc_list)
359 {
360         __be32 *p;
361         int i;
362         __be32 status;
363
364         status = decode_sessionid(xdr, &rc_list->rcl_sessionid);
365         if (status)
366                 goto out;
367
368         status = htonl(NFS4ERR_RESOURCE);
369         p = xdr_inline_decode(xdr, sizeof(uint32_t));
370         if (unlikely(p == NULL))
371                 goto out;
372
373         rc_list->rcl_nrefcalls = ntohl(*p++);
374         if (rc_list->rcl_nrefcalls) {
375                 p = xdr_inline_decode(xdr,
376                              rc_list->rcl_nrefcalls * 2 * sizeof(uint32_t));
377                 if (unlikely(p == NULL))
378                         goto out;
379                 rc_list->rcl_refcalls = kmalloc_array(rc_list->rcl_nrefcalls,
380                                                 sizeof(*rc_list->rcl_refcalls),
381                                                 GFP_KERNEL);
382                 if (unlikely(rc_list->rcl_refcalls == NULL))
383                         goto out;
384                 for (i = 0; i < rc_list->rcl_nrefcalls; i++) {
385                         rc_list->rcl_refcalls[i].rc_sequenceid = ntohl(*p++);
386                         rc_list->rcl_refcalls[i].rc_slotid = ntohl(*p++);
387                 }
388         }
389         status = 0;
390
391 out:
392         return status;
393 }
394
395 static __be32 decode_cb_sequence_args(struct svc_rqst *rqstp,
396                                         struct xdr_stream *xdr,
397                                         void *argp)
398 {
399         struct cb_sequenceargs *args = argp;
400         __be32 *p;
401         int i;
402         __be32 status;
403
404         status = decode_sessionid(xdr, &args->csa_sessionid);
405         if (status)
406                 return status;
407
408         p = xdr_inline_decode(xdr, 5 * sizeof(uint32_t));
409         if (unlikely(p == NULL))
410                 return htonl(NFS4ERR_RESOURCE);
411
412         args->csa_addr = svc_addr(rqstp);
413         args->csa_sequenceid = ntohl(*p++);
414         args->csa_slotid = ntohl(*p++);
415         args->csa_highestslotid = ntohl(*p++);
416         args->csa_cachethis = ntohl(*p++);
417         args->csa_nrclists = ntohl(*p++);
418         args->csa_rclists = NULL;
419         if (args->csa_nrclists) {
420                 args->csa_rclists = kmalloc_array(args->csa_nrclists,
421                                                   sizeof(*args->csa_rclists),
422                                                   GFP_KERNEL);
423                 if (unlikely(args->csa_rclists == NULL))
424                         return htonl(NFS4ERR_RESOURCE);
425
426                 for (i = 0; i < args->csa_nrclists; i++) {
427                         status = decode_rc_list(xdr, &args->csa_rclists[i]);
428                         if (status) {
429                                 args->csa_nrclists = i;
430                                 goto out_free;
431                         }
432                 }
433         }
434         return 0;
435
436 out_free:
437         for (i = 0; i < args->csa_nrclists; i++)
438                 kfree(args->csa_rclists[i].rcl_refcalls);
439         kfree(args->csa_rclists);
440         return status;
441 }
442
443 static __be32 decode_recallany_args(struct svc_rqst *rqstp,
444                                       struct xdr_stream *xdr,
445                                       void *argp)
446 {
447         struct cb_recallanyargs *args = argp;
448         uint32_t bitmap[2];
449         __be32 *p, status;
450
451         p = xdr_inline_decode(xdr, 4);
452         if (unlikely(p == NULL))
453                 return htonl(NFS4ERR_BADXDR);
454         args->craa_objs_to_keep = ntohl(*p++);
455         status = decode_bitmap(xdr, bitmap);
456         if (unlikely(status))
457                 return status;
458         args->craa_type_mask = bitmap[0];
459
460         return 0;
461 }
462
463 static __be32 decode_recallslot_args(struct svc_rqst *rqstp,
464                                         struct xdr_stream *xdr,
465                                         void *argp)
466 {
467         struct cb_recallslotargs *args = argp;
468         __be32 *p;
469
470         p = xdr_inline_decode(xdr, 4);
471         if (unlikely(p == NULL))
472                 return htonl(NFS4ERR_BADXDR);
473         args->crsa_target_highest_slotid = ntohl(*p++);
474         return 0;
475 }
476
477 static __be32 decode_lockowner(struct xdr_stream *xdr, struct cb_notify_lock_args *args)
478 {
479         __be32          *p;
480         unsigned int    len;
481
482         p = xdr_inline_decode(xdr, 12);
483         if (unlikely(p == NULL))
484                 return htonl(NFS4ERR_BADXDR);
485
486         p = xdr_decode_hyper(p, &args->cbnl_owner.clientid);
487         len = be32_to_cpu(*p);
488
489         p = xdr_inline_decode(xdr, len);
490         if (unlikely(p == NULL))
491                 return htonl(NFS4ERR_BADXDR);
492
493         /* Only try to decode if the length is right */
494         if (len == 20) {
495                 p += 2; /* skip "lock id:" */
496                 args->cbnl_owner.s_dev = be32_to_cpu(*p++);
497                 xdr_decode_hyper(p, &args->cbnl_owner.id);
498                 args->cbnl_valid = true;
499         } else {
500                 args->cbnl_owner.s_dev = 0;
501                 args->cbnl_owner.id = 0;
502                 args->cbnl_valid = false;
503         }
504         return 0;
505 }
506
507 static __be32 decode_notify_lock_args(struct svc_rqst *rqstp,
508                 struct xdr_stream *xdr, void *argp)
509 {
510         struct cb_notify_lock_args *args = argp;
511         __be32 status;
512
513         status = decode_fh(xdr, &args->cbnl_fh);
514         if (unlikely(status != 0))
515                 return status;
516         return decode_lockowner(xdr, args);
517 }
518
519 #endif /* CONFIG_NFS_V4_1 */
520 #ifdef CONFIG_NFS_V4_2
521 static __be32 decode_write_response(struct xdr_stream *xdr,
522                                         struct cb_offloadargs *args)
523 {
524         __be32 *p;
525
526         /* skip the always zero field */
527         p = xdr_inline_decode(xdr, 4);
528         if (unlikely(!p))
529                 goto out;
530         p++;
531
532         /* decode count, stable_how, verifier */
533         p = xdr_inline_decode(xdr, 8 + 4);
534         if (unlikely(!p))
535                 goto out;
536         p = xdr_decode_hyper(p, &args->wr_count);
537         args->wr_writeverf.committed = be32_to_cpup(p);
538         p = xdr_inline_decode(xdr, NFS4_VERIFIER_SIZE);
539         if (likely(p)) {
540                 memcpy(&args->wr_writeverf.verifier.data[0], p,
541                         NFS4_VERIFIER_SIZE);
542                 return 0;
543         }
544 out:
545         return htonl(NFS4ERR_RESOURCE);
546 }
547
548 static __be32 decode_offload_args(struct svc_rqst *rqstp,
549                                         struct xdr_stream *xdr,
550                                         void *data)
551 {
552         struct cb_offloadargs *args = data;
553         __be32 *p;
554         __be32 status;
555
556         /* decode fh */
557         status = decode_fh(xdr, &args->coa_fh);
558         if (unlikely(status != 0))
559                 return status;
560
561         /* decode stateid */
562         status = decode_stateid(xdr, &args->coa_stateid);
563         if (unlikely(status != 0))
564                 return status;
565
566         /* decode status */
567         p = xdr_inline_decode(xdr, 4);
568         if (unlikely(!p))
569                 goto out;
570         args->error = ntohl(*p++);
571         if (!args->error) {
572                 status = decode_write_response(xdr, args);
573                 if (unlikely(status != 0))
574                         return status;
575         } else {
576                 p = xdr_inline_decode(xdr, 8);
577                 if (unlikely(!p))
578                         goto out;
579                 p = xdr_decode_hyper(p, &args->wr_count);
580         }
581         return 0;
582 out:
583         return htonl(NFS4ERR_RESOURCE);
584 }
585 #endif /* CONFIG_NFS_V4_2 */
586 static __be32 encode_string(struct xdr_stream *xdr, unsigned int len, const char *str)
587 {
588         if (unlikely(xdr_stream_encode_opaque(xdr, str, len) < 0))
589                 return cpu_to_be32(NFS4ERR_RESOURCE);
590         return 0;
591 }
592
593 static __be32 encode_attr_bitmap(struct xdr_stream *xdr, const uint32_t *bitmap, size_t sz)
594 {
595         if (xdr_stream_encode_uint32_array(xdr, bitmap, sz) < 0)
596                 return cpu_to_be32(NFS4ERR_RESOURCE);
597         return 0;
598 }
599
600 static __be32 encode_attr_change(struct xdr_stream *xdr, const uint32_t *bitmap, uint64_t change)
601 {
602         __be32 *p;
603
604         if (!(bitmap[0] & FATTR4_WORD0_CHANGE))
605                 return 0;
606         p = xdr_reserve_space(xdr, 8);
607         if (unlikely(!p))
608                 return htonl(NFS4ERR_RESOURCE);
609         p = xdr_encode_hyper(p, change);
610         return 0;
611 }
612
613 static __be32 encode_attr_size(struct xdr_stream *xdr, const uint32_t *bitmap, uint64_t size)
614 {
615         __be32 *p;
616
617         if (!(bitmap[0] & FATTR4_WORD0_SIZE))
618                 return 0;
619         p = xdr_reserve_space(xdr, 8);
620         if (unlikely(!p))
621                 return htonl(NFS4ERR_RESOURCE);
622         p = xdr_encode_hyper(p, size);
623         return 0;
624 }
625
626 static __be32 encode_attr_time(struct xdr_stream *xdr, const struct timespec64 *time)
627 {
628         __be32 *p;
629
630         p = xdr_reserve_space(xdr, 12);
631         if (unlikely(!p))
632                 return htonl(NFS4ERR_RESOURCE);
633         p = xdr_encode_hyper(p, time->tv_sec);
634         *p = htonl(time->tv_nsec);
635         return 0;
636 }
637
638 static __be32 encode_attr_ctime(struct xdr_stream *xdr, const uint32_t *bitmap, const struct timespec64 *time)
639 {
640         if (!(bitmap[1] & FATTR4_WORD1_TIME_METADATA))
641                 return 0;
642         return encode_attr_time(xdr,time);
643 }
644
645 static __be32 encode_attr_mtime(struct xdr_stream *xdr, const uint32_t *bitmap, const struct timespec64 *time)
646 {
647         if (!(bitmap[1] & FATTR4_WORD1_TIME_MODIFY))
648                 return 0;
649         return encode_attr_time(xdr,time);
650 }
651
652 static __be32 encode_compound_hdr_res(struct xdr_stream *xdr, struct cb_compound_hdr_res *hdr)
653 {
654         __be32 status;
655
656         hdr->status = xdr_reserve_space(xdr, 4);
657         if (unlikely(hdr->status == NULL))
658                 return htonl(NFS4ERR_RESOURCE);
659         status = encode_string(xdr, hdr->taglen, hdr->tag);
660         if (unlikely(status != 0))
661                 return status;
662         hdr->nops = xdr_reserve_space(xdr, 4);
663         if (unlikely(hdr->nops == NULL))
664                 return htonl(NFS4ERR_RESOURCE);
665         return 0;
666 }
667
668 static __be32 encode_op_hdr(struct xdr_stream *xdr, uint32_t op, __be32 res)
669 {
670         __be32 *p;
671         
672         p = xdr_reserve_space(xdr, 8);
673         if (unlikely(p == NULL))
674                 return htonl(NFS4ERR_RESOURCE_HDR);
675         *p++ = htonl(op);
676         *p = res;
677         return 0;
678 }
679
680 static __be32 encode_getattr_res(struct svc_rqst *rqstp, struct xdr_stream *xdr,
681                 const void *resp)
682 {
683         const struct cb_getattrres *res = resp;
684         __be32 *savep = NULL;
685         __be32 status = res->status;
686         
687         if (unlikely(status != 0))
688                 goto out;
689         status = encode_attr_bitmap(xdr, res->bitmap, ARRAY_SIZE(res->bitmap));
690         if (unlikely(status != 0))
691                 goto out;
692         status = cpu_to_be32(NFS4ERR_RESOURCE);
693         savep = xdr_reserve_space(xdr, sizeof(*savep));
694         if (unlikely(!savep))
695                 goto out;
696         status = encode_attr_change(xdr, res->bitmap, res->change_attr);
697         if (unlikely(status != 0))
698                 goto out;
699         status = encode_attr_size(xdr, res->bitmap, res->size);
700         if (unlikely(status != 0))
701                 goto out;
702         status = encode_attr_ctime(xdr, res->bitmap, &res->ctime);
703         if (unlikely(status != 0))
704                 goto out;
705         status = encode_attr_mtime(xdr, res->bitmap, &res->mtime);
706         *savep = htonl((unsigned int)((char *)xdr->p - (char *)(savep+1)));
707 out:
708         return status;
709 }
710
711 #if defined(CONFIG_NFS_V4_1)
712
713 static __be32 encode_sessionid(struct xdr_stream *xdr,
714                                  const struct nfs4_sessionid *sid)
715 {
716         __be32 *p;
717
718         p = xdr_reserve_space(xdr, NFS4_MAX_SESSIONID_LEN);
719         if (unlikely(p == NULL))
720                 return htonl(NFS4ERR_RESOURCE);
721
722         memcpy(p, sid, NFS4_MAX_SESSIONID_LEN);
723         return 0;
724 }
725
726 static __be32 encode_cb_sequence_res(struct svc_rqst *rqstp,
727                                        struct xdr_stream *xdr,
728                                        const void *resp)
729 {
730         const struct cb_sequenceres *res = resp;
731         __be32 *p;
732         __be32 status = res->csr_status;
733
734         if (unlikely(status != 0))
735                 return status;
736
737         status = encode_sessionid(xdr, &res->csr_sessionid);
738         if (status)
739                 return status;
740
741         p = xdr_reserve_space(xdr, 4 * sizeof(uint32_t));
742         if (unlikely(p == NULL))
743                 return htonl(NFS4ERR_RESOURCE);
744
745         *p++ = htonl(res->csr_sequenceid);
746         *p++ = htonl(res->csr_slotid);
747         *p++ = htonl(res->csr_highestslotid);
748         *p++ = htonl(res->csr_target_highestslotid);
749         return 0;
750 }
751
752 static __be32
753 preprocess_nfs41_op(int nop, unsigned int op_nr, struct callback_op **op)
754 {
755         if (op_nr == OP_CB_SEQUENCE) {
756                 if (nop != 0)
757                         return htonl(NFS4ERR_SEQUENCE_POS);
758         } else {
759                 if (nop == 0)
760                         return htonl(NFS4ERR_OP_NOT_IN_SESSION);
761         }
762
763         switch (op_nr) {
764         case OP_CB_GETATTR:
765         case OP_CB_RECALL:
766         case OP_CB_SEQUENCE:
767         case OP_CB_RECALL_ANY:
768         case OP_CB_RECALL_SLOT:
769         case OP_CB_LAYOUTRECALL:
770         case OP_CB_NOTIFY_DEVICEID:
771         case OP_CB_NOTIFY_LOCK:
772                 *op = &callback_ops[op_nr];
773                 break;
774
775         case OP_CB_NOTIFY:
776         case OP_CB_PUSH_DELEG:
777         case OP_CB_RECALLABLE_OBJ_AVAIL:
778         case OP_CB_WANTS_CANCELLED:
779                 return htonl(NFS4ERR_NOTSUPP);
780
781         default:
782                 return htonl(NFS4ERR_OP_ILLEGAL);
783         }
784
785         return htonl(NFS_OK);
786 }
787
788 static void nfs4_callback_free_slot(struct nfs4_session *session,
789                 struct nfs4_slot *slot)
790 {
791         struct nfs4_slot_table *tbl = &session->bc_slot_table;
792
793         spin_lock(&tbl->slot_tbl_lock);
794         /*
795          * Let the state manager know callback processing done.
796          * A single slot, so highest used slotid is either 0 or -1
797          */
798         nfs4_free_slot(tbl, slot);
799         spin_unlock(&tbl->slot_tbl_lock);
800 }
801
802 static void nfs4_cb_free_slot(struct cb_process_state *cps)
803 {
804         if (cps->slot) {
805                 nfs4_callback_free_slot(cps->clp->cl_session, cps->slot);
806                 cps->slot = NULL;
807         }
808 }
809
810 #else /* CONFIG_NFS_V4_1 */
811
812 static __be32
813 preprocess_nfs41_op(int nop, unsigned int op_nr, struct callback_op **op)
814 {
815         return htonl(NFS4ERR_MINOR_VERS_MISMATCH);
816 }
817
818 static void nfs4_cb_free_slot(struct cb_process_state *cps)
819 {
820 }
821 #endif /* CONFIG_NFS_V4_1 */
822
823 #ifdef CONFIG_NFS_V4_2
824 static __be32
825 preprocess_nfs42_op(int nop, unsigned int op_nr, struct callback_op **op)
826 {
827         __be32 status = preprocess_nfs41_op(nop, op_nr, op);
828         if (status != htonl(NFS4ERR_OP_ILLEGAL))
829                 return status;
830
831         if (op_nr == OP_CB_OFFLOAD) {
832                 *op = &callback_ops[op_nr];
833                 return htonl(NFS_OK);
834         } else
835                 return htonl(NFS4ERR_NOTSUPP);
836         return htonl(NFS4ERR_OP_ILLEGAL);
837 }
838 #else /* CONFIG_NFS_V4_2 */
839 static __be32
840 preprocess_nfs42_op(int nop, unsigned int op_nr, struct callback_op **op)
841 {
842         return htonl(NFS4ERR_MINOR_VERS_MISMATCH);
843 }
844 #endif /* CONFIG_NFS_V4_2 */
845
846 static __be32
847 preprocess_nfs4_op(unsigned int op_nr, struct callback_op **op)
848 {
849         switch (op_nr) {
850         case OP_CB_GETATTR:
851         case OP_CB_RECALL:
852                 *op = &callback_ops[op_nr];
853                 break;
854         default:
855                 return htonl(NFS4ERR_OP_ILLEGAL);
856         }
857
858         return htonl(NFS_OK);
859 }
860
861 static __be32 process_op(int nop, struct svc_rqst *rqstp,
862                          struct cb_process_state *cps)
863 {
864         struct xdr_stream *xdr_out = &rqstp->rq_res_stream;
865         struct callback_op *op = &callback_ops[0];
866         unsigned int op_nr;
867         __be32 status;
868         long maxlen;
869         __be32 res;
870
871         status = decode_op_hdr(&rqstp->rq_arg_stream, &op_nr);
872         if (unlikely(status))
873                 return status;
874
875         switch (cps->minorversion) {
876         case 0:
877                 status = preprocess_nfs4_op(op_nr, &op);
878                 break;
879         case 1:
880                 status = preprocess_nfs41_op(nop, op_nr, &op);
881                 break;
882         case 2:
883                 status = preprocess_nfs42_op(nop, op_nr, &op);
884                 break;
885         default:
886                 status = htonl(NFS4ERR_MINOR_VERS_MISMATCH);
887         }
888
889         if (status == htonl(NFS4ERR_OP_ILLEGAL))
890                 op_nr = OP_CB_ILLEGAL;
891         if (status)
892                 goto encode_hdr;
893
894         if (cps->drc_status) {
895                 status = cps->drc_status;
896                 goto encode_hdr;
897         }
898
899         maxlen = xdr_out->end - xdr_out->p;
900         if (maxlen > 0 && maxlen < PAGE_SIZE) {
901                 status = op->decode_args(rqstp, &rqstp->rq_arg_stream,
902                                          rqstp->rq_argp);
903                 if (likely(status == 0))
904                         status = op->process_op(rqstp->rq_argp, rqstp->rq_resp,
905                                                 cps);
906         } else
907                 status = htonl(NFS4ERR_RESOURCE);
908
909 encode_hdr:
910         res = encode_op_hdr(xdr_out, op_nr, status);
911         if (unlikely(res))
912                 return res;
913         if (op->encode_res != NULL && status == 0)
914                 status = op->encode_res(rqstp, xdr_out, rqstp->rq_resp);
915         return status;
916 }
917
918 /*
919  * Decode, process and encode a COMPOUND
920  */
921 static __be32 nfs4_callback_compound(struct svc_rqst *rqstp)
922 {
923         struct cb_compound_hdr_arg hdr_arg = { 0 };
924         struct cb_compound_hdr_res hdr_res = { NULL };
925         struct cb_process_state cps = {
926                 .drc_status = 0,
927                 .clp = NULL,
928                 .net = SVC_NET(rqstp),
929         };
930         unsigned int nops = 0;
931         __be32 status;
932
933         status = decode_compound_hdr_arg(&rqstp->rq_arg_stream, &hdr_arg);
934         if (status == htonl(NFS4ERR_RESOURCE))
935                 return rpc_garbage_args;
936
937         if (hdr_arg.minorversion == 0) {
938                 cps.clp = nfs4_find_client_ident(SVC_NET(rqstp), hdr_arg.cb_ident);
939                 if (!cps.clp) {
940                         trace_nfs_cb_no_clp(rqstp->rq_xid, hdr_arg.cb_ident);
941                         goto out_invalidcred;
942                 }
943                 if (!check_gss_callback_principal(cps.clp, rqstp)) {
944                         trace_nfs_cb_badprinc(rqstp->rq_xid, hdr_arg.cb_ident);
945                         nfs_put_client(cps.clp);
946                         goto out_invalidcred;
947                 }
948         }
949
950         cps.minorversion = hdr_arg.minorversion;
951         hdr_res.taglen = hdr_arg.taglen;
952         hdr_res.tag = hdr_arg.tag;
953         if (encode_compound_hdr_res(&rqstp->rq_res_stream, &hdr_res) != 0) {
954                 if (cps.clp)
955                         nfs_put_client(cps.clp);
956                 return rpc_system_err;
957         }
958         while (status == 0 && nops != hdr_arg.nops) {
959                 status = process_op(nops, rqstp, &cps);
960                 nops++;
961         }
962
963         /* Buffer overflow in decode_ops_hdr or encode_ops_hdr. Return
964         * resource error in cb_compound status without returning op */
965         if (unlikely(status == htonl(NFS4ERR_RESOURCE_HDR))) {
966                 status = htonl(NFS4ERR_RESOURCE);
967                 nops--;
968         }
969
970         if (svc_is_backchannel(rqstp) && cps.clp) {
971                 rqstp->bc_to_initval = cps.clp->cl_rpcclient->cl_timeout->to_initval;
972                 rqstp->bc_to_retries = cps.clp->cl_rpcclient->cl_timeout->to_retries;
973         }
974
975         *hdr_res.status = status;
976         *hdr_res.nops = htonl(nops);
977         nfs4_cb_free_slot(&cps);
978         nfs_put_client(cps.clp);
979         return rpc_success;
980
981 out_invalidcred:
982         pr_warn_ratelimited("NFS: NFSv4 callback contains invalid cred\n");
983         rqstp->rq_auth_stat = rpc_autherr_badcred;
984         return rpc_success;
985 }
986
987 static int
988 nfs_callback_dispatch(struct svc_rqst *rqstp)
989 {
990         const struct svc_procedure *procp = rqstp->rq_procinfo;
991
992         *rqstp->rq_accept_statp = procp->pc_func(rqstp);
993         return 1;
994 }
995
996 /*
997  * Define NFS4 callback COMPOUND ops.
998  */
999 static struct callback_op callback_ops[] = {
1000         [0] = {
1001                 .res_maxsize = CB_OP_HDR_RES_MAXSZ,
1002         },
1003         [OP_CB_GETATTR] = {
1004                 .process_op = nfs4_callback_getattr,
1005                 .decode_args = decode_getattr_args,
1006                 .encode_res = encode_getattr_res,
1007                 .res_maxsize = CB_OP_GETATTR_RES_MAXSZ,
1008         },
1009         [OP_CB_RECALL] = {
1010                 .process_op = nfs4_callback_recall,
1011                 .decode_args = decode_recall_args,
1012                 .res_maxsize = CB_OP_RECALL_RES_MAXSZ,
1013         },
1014 #if defined(CONFIG_NFS_V4_1)
1015         [OP_CB_LAYOUTRECALL] = {
1016                 .process_op = nfs4_callback_layoutrecall,
1017                 .decode_args = decode_layoutrecall_args,
1018                 .res_maxsize = CB_OP_LAYOUTRECALL_RES_MAXSZ,
1019         },
1020         [OP_CB_NOTIFY_DEVICEID] = {
1021                 .process_op = nfs4_callback_devicenotify,
1022                 .decode_args = decode_devicenotify_args,
1023                 .res_maxsize = CB_OP_DEVICENOTIFY_RES_MAXSZ,
1024         },
1025         [OP_CB_SEQUENCE] = {
1026                 .process_op = nfs4_callback_sequence,
1027                 .decode_args = decode_cb_sequence_args,
1028                 .encode_res = encode_cb_sequence_res,
1029                 .res_maxsize = CB_OP_SEQUENCE_RES_MAXSZ,
1030         },
1031         [OP_CB_RECALL_ANY] = {
1032                 .process_op = nfs4_callback_recallany,
1033                 .decode_args = decode_recallany_args,
1034                 .res_maxsize = CB_OP_RECALLANY_RES_MAXSZ,
1035         },
1036         [OP_CB_RECALL_SLOT] = {
1037                 .process_op = nfs4_callback_recallslot,
1038                 .decode_args = decode_recallslot_args,
1039                 .res_maxsize = CB_OP_RECALLSLOT_RES_MAXSZ,
1040         },
1041         [OP_CB_NOTIFY_LOCK] = {
1042                 .process_op = nfs4_callback_notify_lock,
1043                 .decode_args = decode_notify_lock_args,
1044                 .res_maxsize = CB_OP_NOTIFY_LOCK_RES_MAXSZ,
1045         },
1046 #endif /* CONFIG_NFS_V4_1 */
1047 #ifdef CONFIG_NFS_V4_2
1048         [OP_CB_OFFLOAD] = {
1049                 .process_op = nfs4_callback_offload,
1050                 .decode_args = decode_offload_args,
1051                 .res_maxsize = CB_OP_OFFLOAD_RES_MAXSZ,
1052         },
1053 #endif /* CONFIG_NFS_V4_2 */
1054 };
1055
1056 /*
1057  * Define NFS4 callback procedures
1058  */
1059 static const struct svc_procedure nfs4_callback_procedures1[] = {
1060         [CB_NULL] = {
1061                 .pc_func = nfs4_callback_null,
1062                 .pc_encode = nfs4_encode_void,
1063                 .pc_xdrressize = 1,
1064                 .pc_name = "NULL",
1065         },
1066         [CB_COMPOUND] = {
1067                 .pc_func = nfs4_callback_compound,
1068                 .pc_encode = nfs4_encode_void,
1069                 .pc_argsize = 256,
1070                 .pc_argzero = 256,
1071                 .pc_ressize = 256,
1072                 .pc_xdrressize = NFS4_CALLBACK_BUFSIZE,
1073                 .pc_name = "COMPOUND",
1074         }
1075 };
1076
1077 static DEFINE_PER_CPU_ALIGNED(unsigned long,
1078                               nfs4_callback_count1[ARRAY_SIZE(nfs4_callback_procedures1)]);
1079 const struct svc_version nfs4_callback_version1 = {
1080         .vs_vers = 1,
1081         .vs_nproc = ARRAY_SIZE(nfs4_callback_procedures1),
1082         .vs_proc = nfs4_callback_procedures1,
1083         .vs_count = nfs4_callback_count1,
1084         .vs_xdrsize = NFS4_CALLBACK_XDRSIZE,
1085         .vs_dispatch = nfs_callback_dispatch,
1086         .vs_hidden = true,
1087         .vs_need_cong_ctrl = true,
1088 };
1089
1090 static DEFINE_PER_CPU_ALIGNED(unsigned long,
1091                               nfs4_callback_count4[ARRAY_SIZE(nfs4_callback_procedures1)]);
1092 const struct svc_version nfs4_callback_version4 = {
1093         .vs_vers = 4,
1094         .vs_nproc = ARRAY_SIZE(nfs4_callback_procedures1),
1095         .vs_proc = nfs4_callback_procedures1,
1096         .vs_count = nfs4_callback_count4,
1097         .vs_xdrsize = NFS4_CALLBACK_XDRSIZE,
1098         .vs_dispatch = nfs_callback_dispatch,
1099         .vs_hidden = true,
1100         .vs_need_cong_ctrl = true,
1101 };