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17#include <linux/fs.h>
18#include <linux/file.h>
19#include <linux/splice.h>
20#include <linux/falloc.h>
21#include <linux/fcntl.h>
22#include <linux/namei.h>
23#include <linux/delay.h>
24#include <linux/fsnotify.h>
25#include <linux/posix_acl_xattr.h>
26#include <linux/xattr.h>
27#include <linux/jhash.h>
28#include <linux/ima.h>
29#include <linux/slab.h>
30#include <linux/uaccess.h>
31#include <linux/exportfs.h>
32#include <linux/writeback.h>
33#include <linux/security.h>
34
35#ifdef CONFIG_NFSD_V3
36#include "xdr3.h"
37#endif
38
39#ifdef CONFIG_NFSD_V4
40#include "../internal.h"
41#include "acl.h"
42#include "idmap.h"
43#endif
44
45#include "nfsd.h"
46#include "vfs.h"
47#include "filecache.h"
48#include "trace.h"
49
50#define NFSDDBG_FACILITY NFSDDBG_FILEOP
51
52
53
54
55
56
57
58int
59nfsd_cross_mnt(struct svc_rqst *rqstp, struct dentry **dpp,
60 struct svc_export **expp)
61{
62 struct svc_export *exp = *expp, *exp2 = NULL;
63 struct dentry *dentry = *dpp;
64 struct path path = {.mnt = mntget(exp->ex_path.mnt),
65 .dentry = dget(dentry)};
66 int err = 0;
67
68 err = follow_down(&path);
69 if (err < 0)
70 goto out;
71 if (path.mnt == exp->ex_path.mnt && path.dentry == dentry &&
72 nfsd_mountpoint(dentry, exp) == 2) {
73
74 path_put(&path);
75 goto out;
76 }
77
78 exp2 = rqst_exp_get_by_name(rqstp, &path);
79 if (IS_ERR(exp2)) {
80 err = PTR_ERR(exp2);
81
82
83
84
85
86
87
88 if (err == -ENOENT && !(exp->ex_flags & NFSEXP_V4ROOT))
89 err = 0;
90 path_put(&path);
91 goto out;
92 }
93 if (nfsd_v4client(rqstp) ||
94 (exp->ex_flags & NFSEXP_CROSSMOUNT) || EX_NOHIDE(exp2)) {
95
96
97
98
99
100
101
102 *dpp = path.dentry;
103 path.dentry = dentry;
104 *expp = exp2;
105 exp2 = exp;
106 }
107 path_put(&path);
108 exp_put(exp2);
109out:
110 return err;
111}
112
113static void follow_to_parent(struct path *path)
114{
115 struct dentry *dp;
116
117 while (path->dentry == path->mnt->mnt_root && follow_up(path))
118 ;
119 dp = dget_parent(path->dentry);
120 dput(path->dentry);
121 path->dentry = dp;
122}
123
124static int nfsd_lookup_parent(struct svc_rqst *rqstp, struct dentry *dparent, struct svc_export **exp, struct dentry **dentryp)
125{
126 struct svc_export *exp2;
127 struct path path = {.mnt = mntget((*exp)->ex_path.mnt),
128 .dentry = dget(dparent)};
129
130 follow_to_parent(&path);
131
132 exp2 = rqst_exp_parent(rqstp, &path);
133 if (PTR_ERR(exp2) == -ENOENT) {
134 *dentryp = dget(dparent);
135 } else if (IS_ERR(exp2)) {
136 path_put(&path);
137 return PTR_ERR(exp2);
138 } else {
139 *dentryp = dget(path.dentry);
140 exp_put(*exp);
141 *exp = exp2;
142 }
143 path_put(&path);
144 return 0;
145}
146
147
148
149
150
151
152
153
154
155int nfsd_mountpoint(struct dentry *dentry, struct svc_export *exp)
156{
157 if (!d_inode(dentry))
158 return 0;
159 if (exp->ex_flags & NFSEXP_V4ROOT)
160 return 1;
161 if (nfsd4_is_junction(dentry))
162 return 1;
163 if (d_mountpoint(dentry))
164
165
166
167
168 return 2;
169 return 0;
170}
171
172__be32
173nfsd_lookup_dentry(struct svc_rqst *rqstp, struct svc_fh *fhp,
174 const char *name, unsigned int len,
175 struct svc_export **exp_ret, struct dentry **dentry_ret)
176{
177 struct svc_export *exp;
178 struct dentry *dparent;
179 struct dentry *dentry;
180 int host_err;
181
182 dprintk("nfsd: nfsd_lookup(fh %s, %.*s)\n", SVCFH_fmt(fhp), len,name);
183
184 dparent = fhp->fh_dentry;
185 exp = exp_get(fhp->fh_export);
186
187
188 if (isdotent(name, len)) {
189 if (len==1)
190 dentry = dget(dparent);
191 else if (dparent != exp->ex_path.dentry)
192 dentry = dget_parent(dparent);
193 else if (!EX_NOHIDE(exp) && !nfsd_v4client(rqstp))
194 dentry = dget(dparent);
195 else {
196
197 host_err = nfsd_lookup_parent(rqstp, dparent, &exp, &dentry);
198 if (host_err)
199 goto out_nfserr;
200 }
201 } else {
202
203
204
205
206
207 fh_lock_nested(fhp, I_MUTEX_PARENT);
208 dentry = lookup_one_len(name, dparent, len);
209 host_err = PTR_ERR(dentry);
210 if (IS_ERR(dentry))
211 goto out_nfserr;
212 if (nfsd_mountpoint(dentry, exp)) {
213
214
215
216
217
218
219
220
221 fh_unlock(fhp);
222 if ((host_err = nfsd_cross_mnt(rqstp, &dentry, &exp))) {
223 dput(dentry);
224 goto out_nfserr;
225 }
226 }
227 }
228 *dentry_ret = dentry;
229 *exp_ret = exp;
230 return 0;
231
232out_nfserr:
233 exp_put(exp);
234 return nfserrno(host_err);
235}
236
237
238
239
240
241
242
243
244
245
246
247
248
249__be32
250nfsd_lookup(struct svc_rqst *rqstp, struct svc_fh *fhp, const char *name,
251 unsigned int len, struct svc_fh *resfh)
252{
253 struct svc_export *exp;
254 struct dentry *dentry;
255 __be32 err;
256
257 err = fh_verify(rqstp, fhp, S_IFDIR, NFSD_MAY_EXEC);
258 if (err)
259 return err;
260 err = nfsd_lookup_dentry(rqstp, fhp, name, len, &exp, &dentry);
261 if (err)
262 return err;
263 err = check_nfsd_access(exp, rqstp);
264 if (err)
265 goto out;
266
267
268
269
270 err = fh_compose(resfh, exp, dentry, fhp);
271 if (!err && d_really_is_negative(dentry))
272 err = nfserr_noent;
273out:
274 dput(dentry);
275 exp_put(exp);
276 return err;
277}
278
279
280
281
282static int
283commit_inode_metadata(struct inode *inode)
284{
285 const struct export_operations *export_ops = inode->i_sb->s_export_op;
286
287 if (export_ops->commit_metadata)
288 return export_ops->commit_metadata(inode);
289 return sync_inode_metadata(inode, 1);
290}
291
292static int
293commit_metadata(struct svc_fh *fhp)
294{
295 struct inode *inode = d_inode(fhp->fh_dentry);
296
297 if (!EX_ISSYNC(fhp->fh_export))
298 return 0;
299 return commit_inode_metadata(inode);
300}
301
302
303
304
305
306static void
307nfsd_sanitize_attrs(struct inode *inode, struct iattr *iap)
308{
309
310 if (iap->ia_valid & ATTR_MODE) {
311 iap->ia_mode &= S_IALLUGO;
312 iap->ia_mode |= (inode->i_mode & ~S_IALLUGO);
313 }
314
315
316 if (!S_ISDIR(inode->i_mode) &&
317 ((iap->ia_valid & ATTR_UID) || (iap->ia_valid & ATTR_GID))) {
318 iap->ia_valid |= ATTR_KILL_PRIV;
319 if (iap->ia_valid & ATTR_MODE) {
320
321 iap->ia_mode &= ~S_ISUID;
322 if (iap->ia_mode & S_IXGRP)
323 iap->ia_mode &= ~S_ISGID;
324 } else {
325
326 iap->ia_valid |= (ATTR_KILL_SUID | ATTR_KILL_SGID);
327 }
328 }
329}
330
331static __be32
332nfsd_get_write_access(struct svc_rqst *rqstp, struct svc_fh *fhp,
333 struct iattr *iap)
334{
335 struct inode *inode = d_inode(fhp->fh_dentry);
336 int host_err;
337
338 if (iap->ia_size < inode->i_size) {
339 __be32 err;
340
341 err = nfsd_permission(rqstp, fhp->fh_export, fhp->fh_dentry,
342 NFSD_MAY_TRUNC | NFSD_MAY_OWNER_OVERRIDE);
343 if (err)
344 return err;
345 }
346
347 host_err = get_write_access(inode);
348 if (host_err)
349 goto out_nfserrno;
350
351 host_err = locks_verify_truncate(inode, NULL, iap->ia_size);
352 if (host_err)
353 goto out_put_write_access;
354 return 0;
355
356out_put_write_access:
357 put_write_access(inode);
358out_nfserrno:
359 return nfserrno(host_err);
360}
361
362
363
364
365__be32
366nfsd_setattr(struct svc_rqst *rqstp, struct svc_fh *fhp, struct iattr *iap,
367 int check_guard, time64_t guardtime)
368{
369 struct dentry *dentry;
370 struct inode *inode;
371 int accmode = NFSD_MAY_SATTR;
372 umode_t ftype = 0;
373 __be32 err;
374 int host_err;
375 bool get_write_count;
376 bool size_change = (iap->ia_valid & ATTR_SIZE);
377
378 if (iap->ia_valid & ATTR_SIZE) {
379 accmode |= NFSD_MAY_WRITE|NFSD_MAY_OWNER_OVERRIDE;
380 ftype = S_IFREG;
381 }
382
383
384
385
386
387
388
389
390 if (iap->ia_valid & (ATTR_ATIME | ATTR_MTIME)) {
391 accmode |= NFSD_MAY_OWNER_OVERRIDE;
392 if (!(iap->ia_valid & (ATTR_ATIME_SET | ATTR_MTIME_SET)))
393 accmode |= NFSD_MAY_WRITE;
394 }
395
396
397 get_write_count = !fhp->fh_dentry;
398
399
400 err = fh_verify(rqstp, fhp, ftype, accmode);
401 if (err)
402 return err;
403 if (get_write_count) {
404 host_err = fh_want_write(fhp);
405 if (host_err)
406 goto out;
407 }
408
409 dentry = fhp->fh_dentry;
410 inode = d_inode(dentry);
411
412
413 if (S_ISLNK(inode->i_mode))
414 iap->ia_valid &= ~ATTR_MODE;
415
416 if (!iap->ia_valid)
417 return 0;
418
419 nfsd_sanitize_attrs(inode, iap);
420
421 if (check_guard && guardtime != inode->i_ctime.tv_sec)
422 return nfserr_notsync;
423
424
425
426
427
428
429
430
431 if (size_change) {
432 err = nfsd_get_write_access(rqstp, fhp, iap);
433 if (err)
434 return err;
435 }
436
437 fh_lock(fhp);
438 if (size_change) {
439
440
441
442
443
444
445
446 struct iattr size_attr = {
447 .ia_valid = ATTR_SIZE | ATTR_CTIME | ATTR_MTIME,
448 .ia_size = iap->ia_size,
449 };
450
451 host_err = notify_change(&init_user_ns, dentry, &size_attr, NULL);
452 if (host_err)
453 goto out_unlock;
454 iap->ia_valid &= ~ATTR_SIZE;
455
456
457
458
459
460
461 if ((iap->ia_valid & ~ATTR_MTIME) == 0)
462 goto out_unlock;
463 }
464
465 iap->ia_valid |= ATTR_CTIME;
466 host_err = notify_change(&init_user_ns, dentry, iap, NULL);
467
468out_unlock:
469 fh_unlock(fhp);
470 if (size_change)
471 put_write_access(inode);
472out:
473 if (!host_err)
474 host_err = commit_metadata(fhp);
475 return nfserrno(host_err);
476}
477
478#if defined(CONFIG_NFSD_V4)
479
480
481
482#define NFSD_JUNCTION_XATTR_NAME XATTR_TRUSTED_PREFIX "junction.nfs"
483
484
485
486
487
488
489
490
491
492int nfsd4_is_junction(struct dentry *dentry)
493{
494 struct inode *inode = d_inode(dentry);
495
496 if (inode == NULL)
497 return 0;
498 if (inode->i_mode & S_IXUGO)
499 return 0;
500 if (!(inode->i_mode & S_ISVTX))
501 return 0;
502 if (vfs_getxattr(&init_user_ns, dentry, NFSD_JUNCTION_XATTR_NAME,
503 NULL, 0) <= 0)
504 return 0;
505 return 1;
506}
507#ifdef CONFIG_NFSD_V4_SECURITY_LABEL
508__be32 nfsd4_set_nfs4_label(struct svc_rqst *rqstp, struct svc_fh *fhp,
509 struct xdr_netobj *label)
510{
511 __be32 error;
512 int host_error;
513 struct dentry *dentry;
514
515 error = fh_verify(rqstp, fhp, 0 , NFSD_MAY_SATTR);
516 if (error)
517 return error;
518
519 dentry = fhp->fh_dentry;
520
521 inode_lock(d_inode(dentry));
522 host_error = security_inode_setsecctx(dentry, label->data, label->len);
523 inode_unlock(d_inode(dentry));
524 return nfserrno(host_error);
525}
526#else
527__be32 nfsd4_set_nfs4_label(struct svc_rqst *rqstp, struct svc_fh *fhp,
528 struct xdr_netobj *label)
529{
530 return nfserr_notsupp;
531}
532#endif
533
534__be32 nfsd4_clone_file_range(struct nfsd_file *nf_src, u64 src_pos,
535 struct nfsd_file *nf_dst, u64 dst_pos, u64 count, bool sync)
536{
537 struct file *src = nf_src->nf_file;
538 struct file *dst = nf_dst->nf_file;
539 loff_t cloned;
540 __be32 ret = 0;
541
542 down_write(&nf_dst->nf_rwsem);
543 cloned = vfs_clone_file_range(src, src_pos, dst, dst_pos, count, 0);
544 if (cloned < 0) {
545 ret = nfserrno(cloned);
546 goto out_err;
547 }
548 if (count && cloned != count) {
549 ret = nfserrno(-EINVAL);
550 goto out_err;
551 }
552 if (sync) {
553 loff_t dst_end = count ? dst_pos + count - 1 : LLONG_MAX;
554 int status = vfs_fsync_range(dst, dst_pos, dst_end, 0);
555
556 if (!status)
557 status = commit_inode_metadata(file_inode(src));
558 if (status < 0) {
559 nfsd_reset_boot_verifier(net_generic(nf_dst->nf_net,
560 nfsd_net_id));
561 ret = nfserrno(status);
562 }
563 }
564out_err:
565 up_write(&nf_dst->nf_rwsem);
566 return ret;
567}
568
569ssize_t nfsd_copy_file_range(struct file *src, u64 src_pos, struct file *dst,
570 u64 dst_pos, u64 count)
571{
572
573
574
575
576
577
578
579
580
581 count = min_t(u64, count, 1 << 22);
582 return vfs_copy_file_range(src, src_pos, dst, dst_pos, count, 0);
583}
584
585__be32 nfsd4_vfs_fallocate(struct svc_rqst *rqstp, struct svc_fh *fhp,
586 struct file *file, loff_t offset, loff_t len,
587 int flags)
588{
589 int error;
590
591 if (!S_ISREG(file_inode(file)->i_mode))
592 return nfserr_inval;
593
594 error = vfs_fallocate(file, flags, offset, len);
595 if (!error)
596 error = commit_metadata(fhp);
597
598 return nfserrno(error);
599}
600#endif
601
602#ifdef CONFIG_NFSD_V3
603
604
605
606struct accessmap {
607 u32 access;
608 int how;
609};
610static struct accessmap nfs3_regaccess[] = {
611 { NFS3_ACCESS_READ, NFSD_MAY_READ },
612 { NFS3_ACCESS_EXECUTE, NFSD_MAY_EXEC },
613 { NFS3_ACCESS_MODIFY, NFSD_MAY_WRITE|NFSD_MAY_TRUNC },
614 { NFS3_ACCESS_EXTEND, NFSD_MAY_WRITE },
615
616#ifdef CONFIG_NFSD_V4
617 { NFS4_ACCESS_XAREAD, NFSD_MAY_READ },
618 { NFS4_ACCESS_XAWRITE, NFSD_MAY_WRITE },
619 { NFS4_ACCESS_XALIST, NFSD_MAY_READ },
620#endif
621
622 { 0, 0 }
623};
624
625static struct accessmap nfs3_diraccess[] = {
626 { NFS3_ACCESS_READ, NFSD_MAY_READ },
627 { NFS3_ACCESS_LOOKUP, NFSD_MAY_EXEC },
628 { NFS3_ACCESS_MODIFY, NFSD_MAY_EXEC|NFSD_MAY_WRITE|NFSD_MAY_TRUNC},
629 { NFS3_ACCESS_EXTEND, NFSD_MAY_EXEC|NFSD_MAY_WRITE },
630 { NFS3_ACCESS_DELETE, NFSD_MAY_REMOVE },
631
632#ifdef CONFIG_NFSD_V4
633 { NFS4_ACCESS_XAREAD, NFSD_MAY_READ },
634 { NFS4_ACCESS_XAWRITE, NFSD_MAY_WRITE },
635 { NFS4_ACCESS_XALIST, NFSD_MAY_READ },
636#endif
637
638 { 0, 0 }
639};
640
641static struct accessmap nfs3_anyaccess[] = {
642
643
644
645
646
647
648
649 { NFS3_ACCESS_READ, NFSD_MAY_READ },
650 { NFS3_ACCESS_EXECUTE, NFSD_MAY_EXEC },
651 { NFS3_ACCESS_MODIFY, NFSD_MAY_WRITE|NFSD_MAY_LOCAL_ACCESS },
652 { NFS3_ACCESS_EXTEND, NFSD_MAY_WRITE|NFSD_MAY_LOCAL_ACCESS },
653
654 { 0, 0 }
655};
656
657__be32
658nfsd_access(struct svc_rqst *rqstp, struct svc_fh *fhp, u32 *access, u32 *supported)
659{
660 struct accessmap *map;
661 struct svc_export *export;
662 struct dentry *dentry;
663 u32 query, result = 0, sresult = 0;
664 __be32 error;
665
666 error = fh_verify(rqstp, fhp, 0, NFSD_MAY_NOP);
667 if (error)
668 goto out;
669
670 export = fhp->fh_export;
671 dentry = fhp->fh_dentry;
672
673 if (d_is_reg(dentry))
674 map = nfs3_regaccess;
675 else if (d_is_dir(dentry))
676 map = nfs3_diraccess;
677 else
678 map = nfs3_anyaccess;
679
680
681 query = *access;
682 for (; map->access; map++) {
683 if (map->access & query) {
684 __be32 err2;
685
686 sresult |= map->access;
687
688 err2 = nfsd_permission(rqstp, export, dentry, map->how);
689 switch (err2) {
690 case nfs_ok:
691 result |= map->access;
692 break;
693
694
695
696 case nfserr_rofs:
697 case nfserr_acces:
698 case nfserr_perm:
699
700 break;
701 default:
702 error = err2;
703 goto out;
704 }
705 }
706 }
707 *access = result;
708 if (supported)
709 *supported = sresult;
710
711 out:
712 return error;
713}
714#endif
715
716int nfsd_open_break_lease(struct inode *inode, int access)
717{
718 unsigned int mode;
719
720 if (access & NFSD_MAY_NOT_BREAK_LEASE)
721 return 0;
722 mode = (access & NFSD_MAY_WRITE) ? O_WRONLY : O_RDONLY;
723 return break_lease(inode, mode | O_NONBLOCK);
724}
725
726
727
728
729
730
731
732static __be32
733__nfsd_open(struct svc_rqst *rqstp, struct svc_fh *fhp, umode_t type,
734 int may_flags, struct file **filp)
735{
736 struct path path;
737 struct inode *inode;
738 struct file *file;
739 int flags = O_RDONLY|O_LARGEFILE;
740 __be32 err;
741 int host_err = 0;
742
743 path.mnt = fhp->fh_export->ex_path.mnt;
744 path.dentry = fhp->fh_dentry;
745 inode = d_inode(path.dentry);
746
747
748
749
750 err = nfserr_perm;
751 if (IS_APPEND(inode) && (may_flags & NFSD_MAY_WRITE))
752 goto out;
753
754
755
756
757
758 if (S_ISREG((inode)->i_mode) && mandatory_lock(inode))
759 goto out;
760
761 if (!inode->i_fop)
762 goto out;
763
764 host_err = nfsd_open_break_lease(inode, may_flags);
765 if (host_err)
766 goto out_nfserr;
767
768 if (may_flags & NFSD_MAY_WRITE) {
769 if (may_flags & NFSD_MAY_READ)
770 flags = O_RDWR|O_LARGEFILE;
771 else
772 flags = O_WRONLY|O_LARGEFILE;
773 }
774
775 file = dentry_open(&path, flags, current_cred());
776 if (IS_ERR(file)) {
777 host_err = PTR_ERR(file);
778 goto out_nfserr;
779 }
780
781 host_err = ima_file_check(file, may_flags);
782 if (host_err) {
783 fput(file);
784 goto out_nfserr;
785 }
786
787 if (may_flags & NFSD_MAY_64BIT_COOKIE)
788 file->f_mode |= FMODE_64BITHASH;
789 else
790 file->f_mode |= FMODE_32BITHASH;
791
792 *filp = file;
793out_nfserr:
794 err = nfserrno(host_err);
795out:
796 return err;
797}
798
799__be32
800nfsd_open(struct svc_rqst *rqstp, struct svc_fh *fhp, umode_t type,
801 int may_flags, struct file **filp)
802{
803 __be32 err;
804
805 validate_process_creds();
806
807
808
809
810
811
812
813
814
815
816
817 if (type == S_IFREG)
818 may_flags |= NFSD_MAY_OWNER_OVERRIDE;
819 err = fh_verify(rqstp, fhp, type, may_flags);
820 if (!err)
821 err = __nfsd_open(rqstp, fhp, type, may_flags, filp);
822 validate_process_creds();
823 return err;
824}
825
826__be32
827nfsd_open_verified(struct svc_rqst *rqstp, struct svc_fh *fhp, umode_t type,
828 int may_flags, struct file **filp)
829{
830 __be32 err;
831
832 validate_process_creds();
833 err = __nfsd_open(rqstp, fhp, type, may_flags, filp);
834 validate_process_creds();
835 return err;
836}
837
838
839
840
841
842
843static int
844nfsd_splice_actor(struct pipe_inode_info *pipe, struct pipe_buffer *buf,
845 struct splice_desc *sd)
846{
847 struct svc_rqst *rqstp = sd->u.data;
848 struct page **pp = rqstp->rq_next_page;
849 struct page *page = buf->page;
850 size_t size;
851
852 size = sd->len;
853
854 if (rqstp->rq_res.page_len == 0) {
855 get_page(page);
856 put_page(*rqstp->rq_next_page);
857 *(rqstp->rq_next_page++) = page;
858 rqstp->rq_res.page_base = buf->offset;
859 rqstp->rq_res.page_len = size;
860 } else if (page != pp[-1]) {
861 get_page(page);
862 if (*rqstp->rq_next_page)
863 put_page(*rqstp->rq_next_page);
864 *(rqstp->rq_next_page++) = page;
865 rqstp->rq_res.page_len += size;
866 } else
867 rqstp->rq_res.page_len += size;
868
869 return size;
870}
871
872static int nfsd_direct_splice_actor(struct pipe_inode_info *pipe,
873 struct splice_desc *sd)
874{
875 return __splice_from_pipe(pipe, sd, nfsd_splice_actor);
876}
877
878static u32 nfsd_eof_on_read(struct file *file, loff_t offset, ssize_t len,
879 size_t expected)
880{
881 if (expected != 0 && len == 0)
882 return 1;
883 if (offset+len >= i_size_read(file_inode(file)))
884 return 1;
885 return 0;
886}
887
888static __be32 nfsd_finish_read(struct svc_rqst *rqstp, struct svc_fh *fhp,
889 struct file *file, loff_t offset,
890 unsigned long *count, u32 *eof, ssize_t host_err)
891{
892 if (host_err >= 0) {
893 nfsd_stats_io_read_add(fhp->fh_export, host_err);
894 *eof = nfsd_eof_on_read(file, offset, host_err, *count);
895 *count = host_err;
896 fsnotify_access(file);
897 trace_nfsd_read_io_done(rqstp, fhp, offset, *count);
898 return 0;
899 } else {
900 trace_nfsd_read_err(rqstp, fhp, offset, host_err);
901 return nfserrno(host_err);
902 }
903}
904
905__be32 nfsd_splice_read(struct svc_rqst *rqstp, struct svc_fh *fhp,
906 struct file *file, loff_t offset, unsigned long *count,
907 u32 *eof)
908{
909 struct splice_desc sd = {
910 .len = 0,
911 .total_len = *count,
912 .pos = offset,
913 .u.data = rqstp,
914 };
915 ssize_t host_err;
916
917 trace_nfsd_read_splice(rqstp, fhp, offset, *count);
918 rqstp->rq_next_page = rqstp->rq_respages + 1;
919 host_err = splice_direct_to_actor(file, &sd, nfsd_direct_splice_actor);
920 return nfsd_finish_read(rqstp, fhp, file, offset, count, eof, host_err);
921}
922
923__be32 nfsd_readv(struct svc_rqst *rqstp, struct svc_fh *fhp,
924 struct file *file, loff_t offset,
925 struct kvec *vec, int vlen, unsigned long *count,
926 u32 *eof)
927{
928 struct iov_iter iter;
929 loff_t ppos = offset;
930 ssize_t host_err;
931
932 trace_nfsd_read_vector(rqstp, fhp, offset, *count);
933 iov_iter_kvec(&iter, READ, vec, vlen, *count);
934 host_err = vfs_iter_read(file, &iter, &ppos, 0);
935 return nfsd_finish_read(rqstp, fhp, file, offset, count, eof, host_err);
936}
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952static int wait_for_concurrent_writes(struct file *file)
953{
954 struct inode *inode = file_inode(file);
955 static ino_t last_ino;
956 static dev_t last_dev;
957 int err = 0;
958
959 if (atomic_read(&inode->i_writecount) > 1
960 || (last_ino == inode->i_ino && last_dev == inode->i_sb->s_dev)) {
961 dprintk("nfsd: write defer %d\n", task_pid_nr(current));
962 msleep(10);
963 dprintk("nfsd: write resume %d\n", task_pid_nr(current));
964 }
965
966 if (inode->i_state & I_DIRTY) {
967 dprintk("nfsd: write sync %d\n", task_pid_nr(current));
968 err = vfs_fsync(file, 0);
969 }
970 last_ino = inode->i_ino;
971 last_dev = inode->i_sb->s_dev;
972 return err;
973}
974
975__be32
976nfsd_vfs_write(struct svc_rqst *rqstp, struct svc_fh *fhp, struct nfsd_file *nf,
977 loff_t offset, struct kvec *vec, int vlen,
978 unsigned long *cnt, int stable,
979 __be32 *verf)
980{
981 struct file *file = nf->nf_file;
982 struct super_block *sb = file_inode(file)->i_sb;
983 struct svc_export *exp;
984 struct iov_iter iter;
985 __be32 nfserr;
986 int host_err;
987 int use_wgather;
988 loff_t pos = offset;
989 unsigned long exp_op_flags = 0;
990 unsigned int pflags = current->flags;
991 rwf_t flags = 0;
992 bool restore_flags = false;
993
994 trace_nfsd_write_opened(rqstp, fhp, offset, *cnt);
995
996 if (sb->s_export_op)
997 exp_op_flags = sb->s_export_op->flags;
998
999 if (test_bit(RQ_LOCAL, &rqstp->rq_flags) &&
1000 !(exp_op_flags & EXPORT_OP_REMOTE_FS)) {
1001
1002
1003
1004
1005
1006
1007
1008 current->flags |= PF_LOCAL_THROTTLE;
1009 restore_flags = true;
1010 }
1011
1012 exp = fhp->fh_export;
1013 use_wgather = (rqstp->rq_vers == 2) && EX_WGATHER(exp);
1014
1015 if (!EX_ISSYNC(exp))
1016 stable = NFS_UNSTABLE;
1017
1018 if (stable && !use_wgather)
1019 flags |= RWF_SYNC;
1020
1021 iov_iter_kvec(&iter, WRITE, vec, vlen, *cnt);
1022 if (flags & RWF_SYNC) {
1023 down_write(&nf->nf_rwsem);
1024 host_err = vfs_iter_write(file, &iter, &pos, flags);
1025 if (host_err < 0)
1026 nfsd_reset_boot_verifier(net_generic(SVC_NET(rqstp),
1027 nfsd_net_id));
1028 up_write(&nf->nf_rwsem);
1029 } else {
1030 down_read(&nf->nf_rwsem);
1031 if (verf)
1032 nfsd_copy_boot_verifier(verf,
1033 net_generic(SVC_NET(rqstp),
1034 nfsd_net_id));
1035 host_err = vfs_iter_write(file, &iter, &pos, flags);
1036 up_read(&nf->nf_rwsem);
1037 }
1038 if (host_err < 0) {
1039 nfsd_reset_boot_verifier(net_generic(SVC_NET(rqstp),
1040 nfsd_net_id));
1041 goto out_nfserr;
1042 }
1043 *cnt = host_err;
1044 nfsd_stats_io_write_add(exp, *cnt);
1045 fsnotify_modify(file);
1046
1047 if (stable && use_wgather) {
1048 host_err = wait_for_concurrent_writes(file);
1049 if (host_err < 0)
1050 nfsd_reset_boot_verifier(net_generic(SVC_NET(rqstp),
1051 nfsd_net_id));
1052 }
1053
1054out_nfserr:
1055 if (host_err >= 0) {
1056 trace_nfsd_write_io_done(rqstp, fhp, offset, *cnt);
1057 nfserr = nfs_ok;
1058 } else {
1059 trace_nfsd_write_err(rqstp, fhp, offset, host_err);
1060 nfserr = nfserrno(host_err);
1061 }
1062 if (restore_flags)
1063 current_restore_flags(pflags, PF_LOCAL_THROTTLE);
1064 return nfserr;
1065}
1066
1067
1068
1069
1070
1071
1072__be32 nfsd_read(struct svc_rqst *rqstp, struct svc_fh *fhp,
1073 loff_t offset, struct kvec *vec, int vlen, unsigned long *count,
1074 u32 *eof)
1075{
1076 struct nfsd_file *nf;
1077 struct file *file;
1078 __be32 err;
1079
1080 trace_nfsd_read_start(rqstp, fhp, offset, *count);
1081 err = nfsd_file_acquire(rqstp, fhp, NFSD_MAY_READ, &nf);
1082 if (err)
1083 return err;
1084
1085 file = nf->nf_file;
1086 if (file->f_op->splice_read && test_bit(RQ_SPLICE_OK, &rqstp->rq_flags))
1087 err = nfsd_splice_read(rqstp, fhp, file, offset, count, eof);
1088 else
1089 err = nfsd_readv(rqstp, fhp, file, offset, vec, vlen, count, eof);
1090
1091 nfsd_file_put(nf);
1092
1093 trace_nfsd_read_done(rqstp, fhp, offset, *count);
1094
1095 return err;
1096}
1097
1098
1099
1100
1101
1102
1103__be32
1104nfsd_write(struct svc_rqst *rqstp, struct svc_fh *fhp, loff_t offset,
1105 struct kvec *vec, int vlen, unsigned long *cnt, int stable,
1106 __be32 *verf)
1107{
1108 struct nfsd_file *nf;
1109 __be32 err;
1110
1111 trace_nfsd_write_start(rqstp, fhp, offset, *cnt);
1112
1113 err = nfsd_file_acquire(rqstp, fhp, NFSD_MAY_WRITE, &nf);
1114 if (err)
1115 goto out;
1116
1117 err = nfsd_vfs_write(rqstp, fhp, nf, offset, vec,
1118 vlen, cnt, stable, verf);
1119 nfsd_file_put(nf);
1120out:
1121 trace_nfsd_write_done(rqstp, fhp, offset, *cnt);
1122 return err;
1123}
1124
1125#ifdef CONFIG_NFSD_V3
1126static int
1127nfsd_filemap_write_and_wait_range(struct nfsd_file *nf, loff_t offset,
1128 loff_t end)
1129{
1130 struct address_space *mapping = nf->nf_file->f_mapping;
1131 int ret = filemap_fdatawrite_range(mapping, offset, end);
1132
1133 if (ret)
1134 return ret;
1135 filemap_fdatawait_range_keep_errors(mapping, offset, end);
1136 return 0;
1137}
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148__be32
1149nfsd_commit(struct svc_rqst *rqstp, struct svc_fh *fhp,
1150 loff_t offset, unsigned long count, __be32 *verf)
1151{
1152 struct nfsd_file *nf;
1153 loff_t end = LLONG_MAX;
1154 __be32 err = nfserr_inval;
1155
1156 if (offset < 0)
1157 goto out;
1158 if (count != 0) {
1159 end = offset + (loff_t)count - 1;
1160 if (end < offset)
1161 goto out;
1162 }
1163
1164 err = nfsd_file_acquire(rqstp, fhp,
1165 NFSD_MAY_WRITE|NFSD_MAY_NOT_BREAK_LEASE, &nf);
1166 if (err)
1167 goto out;
1168 if (EX_ISSYNC(fhp->fh_export)) {
1169 int err2 = nfsd_filemap_write_and_wait_range(nf, offset, end);
1170
1171 down_write(&nf->nf_rwsem);
1172 if (!err2)
1173 err2 = vfs_fsync_range(nf->nf_file, offset, end, 0);
1174 switch (err2) {
1175 case 0:
1176 nfsd_copy_boot_verifier(verf, net_generic(nf->nf_net,
1177 nfsd_net_id));
1178 break;
1179 case -EINVAL:
1180 err = nfserr_notsupp;
1181 break;
1182 default:
1183 err = nfserrno(err2);
1184 nfsd_reset_boot_verifier(net_generic(nf->nf_net,
1185 nfsd_net_id));
1186 }
1187 up_write(&nf->nf_rwsem);
1188 } else
1189 nfsd_copy_boot_verifier(verf, net_generic(nf->nf_net,
1190 nfsd_net_id));
1191
1192 nfsd_file_put(nf);
1193out:
1194 return err;
1195}
1196#endif
1197
1198static __be32
1199nfsd_create_setattr(struct svc_rqst *rqstp, struct svc_fh *resfhp,
1200 struct iattr *iap)
1201{
1202
1203
1204
1205 iap->ia_valid &= ~ATTR_MODE;
1206
1207
1208
1209
1210
1211 if (!uid_eq(current_fsuid(), GLOBAL_ROOT_UID))
1212 iap->ia_valid &= ~(ATTR_UID|ATTR_GID);
1213 if (iap->ia_valid)
1214 return nfsd_setattr(rqstp, resfhp, iap, 0, (time64_t)0);
1215
1216 return nfserrno(commit_metadata(resfhp));
1217}
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227static void
1228nfsd_check_ignore_resizing(struct iattr *iap)
1229{
1230 if ((iap->ia_valid & ATTR_SIZE) && (iap->ia_size == 0))
1231 iap->ia_valid &= ~ATTR_SIZE;
1232}
1233
1234
1235__be32
1236nfsd_create_locked(struct svc_rqst *rqstp, struct svc_fh *fhp,
1237 char *fname, int flen, struct iattr *iap,
1238 int type, dev_t rdev, struct svc_fh *resfhp)
1239{
1240 struct dentry *dentry, *dchild;
1241 struct inode *dirp;
1242 __be32 err;
1243 __be32 err2;
1244 int host_err;
1245
1246 dentry = fhp->fh_dentry;
1247 dirp = d_inode(dentry);
1248
1249 dchild = dget(resfhp->fh_dentry);
1250 if (!fhp->fh_locked) {
1251 WARN_ONCE(1, "nfsd_create: parent %pd2 not locked!\n",
1252 dentry);
1253 err = nfserr_io;
1254 goto out;
1255 }
1256
1257 err = nfsd_permission(rqstp, fhp->fh_export, dentry, NFSD_MAY_CREATE);
1258 if (err)
1259 goto out;
1260
1261 if (!(iap->ia_valid & ATTR_MODE))
1262 iap->ia_mode = 0;
1263 iap->ia_mode = (iap->ia_mode & S_IALLUGO) | type;
1264
1265 if (!IS_POSIXACL(dirp))
1266 iap->ia_mode &= ~current_umask();
1267
1268 err = 0;
1269 host_err = 0;
1270 switch (type) {
1271 case S_IFREG:
1272 host_err = vfs_create(&init_user_ns, dirp, dchild, iap->ia_mode, true);
1273 if (!host_err)
1274 nfsd_check_ignore_resizing(iap);
1275 break;
1276 case S_IFDIR:
1277 host_err = vfs_mkdir(&init_user_ns, dirp, dchild, iap->ia_mode);
1278 if (!host_err && unlikely(d_unhashed(dchild))) {
1279 struct dentry *d;
1280 d = lookup_one_len(dchild->d_name.name,
1281 dchild->d_parent,
1282 dchild->d_name.len);
1283 if (IS_ERR(d)) {
1284 host_err = PTR_ERR(d);
1285 break;
1286 }
1287 if (unlikely(d_is_negative(d))) {
1288 dput(d);
1289 err = nfserr_serverfault;
1290 goto out;
1291 }
1292 dput(resfhp->fh_dentry);
1293 resfhp->fh_dentry = dget(d);
1294 err = fh_update(resfhp);
1295 dput(dchild);
1296 dchild = d;
1297 if (err)
1298 goto out;
1299 }
1300 break;
1301 case S_IFCHR:
1302 case S_IFBLK:
1303 case S_IFIFO:
1304 case S_IFSOCK:
1305 host_err = vfs_mknod(&init_user_ns, dirp, dchild,
1306 iap->ia_mode, rdev);
1307 break;
1308 default:
1309 printk(KERN_WARNING "nfsd: bad file type %o in nfsd_create\n",
1310 type);
1311 host_err = -EINVAL;
1312 }
1313 if (host_err < 0)
1314 goto out_nfserr;
1315
1316 err = nfsd_create_setattr(rqstp, resfhp, iap);
1317
1318
1319
1320
1321
1322
1323
1324 err2 = nfserrno(commit_metadata(fhp));
1325 if (err2)
1326 err = err2;
1327
1328
1329
1330 if (!err)
1331 err = fh_update(resfhp);
1332out:
1333 dput(dchild);
1334 return err;
1335
1336out_nfserr:
1337 err = nfserrno(host_err);
1338 goto out;
1339}
1340
1341
1342
1343
1344
1345
1346
1347__be32
1348nfsd_create(struct svc_rqst *rqstp, struct svc_fh *fhp,
1349 char *fname, int flen, struct iattr *iap,
1350 int type, dev_t rdev, struct svc_fh *resfhp)
1351{
1352 struct dentry *dentry, *dchild = NULL;
1353 __be32 err;
1354 int host_err;
1355
1356 if (isdotent(fname, flen))
1357 return nfserr_exist;
1358
1359 err = fh_verify(rqstp, fhp, S_IFDIR, NFSD_MAY_NOP);
1360 if (err)
1361 return err;
1362
1363 dentry = fhp->fh_dentry;
1364
1365 host_err = fh_want_write(fhp);
1366 if (host_err)
1367 return nfserrno(host_err);
1368
1369 fh_lock_nested(fhp, I_MUTEX_PARENT);
1370 dchild = lookup_one_len(fname, dentry, flen);
1371 host_err = PTR_ERR(dchild);
1372 if (IS_ERR(dchild))
1373 return nfserrno(host_err);
1374 err = fh_compose(resfhp, fhp->fh_export, dchild, fhp);
1375
1376
1377
1378
1379 dput(dchild);
1380 if (err)
1381 return err;
1382 return nfsd_create_locked(rqstp, fhp, fname, flen, iap, type,
1383 rdev, resfhp);
1384}
1385
1386#ifdef CONFIG_NFSD_V3
1387
1388
1389
1390
1391__be32
1392do_nfsd_create(struct svc_rqst *rqstp, struct svc_fh *fhp,
1393 char *fname, int flen, struct iattr *iap,
1394 struct svc_fh *resfhp, int createmode, u32 *verifier,
1395 bool *truncp, bool *created)
1396{
1397 struct dentry *dentry, *dchild = NULL;
1398 struct inode *dirp;
1399 __be32 err;
1400 int host_err;
1401 __u32 v_mtime=0, v_atime=0;
1402
1403 err = nfserr_perm;
1404 if (!flen)
1405 goto out;
1406 err = nfserr_exist;
1407 if (isdotent(fname, flen))
1408 goto out;
1409 if (!(iap->ia_valid & ATTR_MODE))
1410 iap->ia_mode = 0;
1411 err = fh_verify(rqstp, fhp, S_IFDIR, NFSD_MAY_EXEC);
1412 if (err)
1413 goto out;
1414
1415 dentry = fhp->fh_dentry;
1416 dirp = d_inode(dentry);
1417
1418 host_err = fh_want_write(fhp);
1419 if (host_err)
1420 goto out_nfserr;
1421
1422 fh_lock_nested(fhp, I_MUTEX_PARENT);
1423
1424
1425
1426
1427 dchild = lookup_one_len(fname, dentry, flen);
1428 host_err = PTR_ERR(dchild);
1429 if (IS_ERR(dchild))
1430 goto out_nfserr;
1431
1432
1433 if (d_really_is_negative(dchild)) {
1434 err = fh_verify(rqstp, fhp, S_IFDIR, NFSD_MAY_CREATE);
1435 if (err)
1436 goto out;
1437 }
1438
1439 err = fh_compose(resfhp, fhp->fh_export, dchild, fhp);
1440 if (err)
1441 goto out;
1442
1443 if (nfsd_create_is_exclusive(createmode)) {
1444
1445
1446
1447
1448
1449
1450 v_mtime = verifier[0]&0x7fffffff;
1451 v_atime = verifier[1]&0x7fffffff;
1452 }
1453
1454 if (d_really_is_positive(dchild)) {
1455 err = 0;
1456
1457 switch (createmode) {
1458 case NFS3_CREATE_UNCHECKED:
1459 if (! d_is_reg(dchild))
1460 goto out;
1461 else if (truncp) {
1462
1463
1464
1465
1466
1467
1468
1469 *truncp = (iap->ia_valid & ATTR_SIZE) && !iap->ia_size;
1470 }
1471 else {
1472 iap->ia_valid &= ATTR_SIZE;
1473 goto set_attr;
1474 }
1475 break;
1476 case NFS3_CREATE_EXCLUSIVE:
1477 if ( d_inode(dchild)->i_mtime.tv_sec == v_mtime
1478 && d_inode(dchild)->i_atime.tv_sec == v_atime
1479 && d_inode(dchild)->i_size == 0 ) {
1480 if (created)
1481 *created = true;
1482 break;
1483 }
1484 fallthrough;
1485 case NFS4_CREATE_EXCLUSIVE4_1:
1486 if ( d_inode(dchild)->i_mtime.tv_sec == v_mtime
1487 && d_inode(dchild)->i_atime.tv_sec == v_atime
1488 && d_inode(dchild)->i_size == 0 ) {
1489 if (created)
1490 *created = true;
1491 goto set_attr;
1492 }
1493 fallthrough;
1494 case NFS3_CREATE_GUARDED:
1495 err = nfserr_exist;
1496 }
1497 fh_drop_write(fhp);
1498 goto out;
1499 }
1500
1501 if (!IS_POSIXACL(dirp))
1502 iap->ia_mode &= ~current_umask();
1503
1504 host_err = vfs_create(&init_user_ns, dirp, dchild, iap->ia_mode, true);
1505 if (host_err < 0) {
1506 fh_drop_write(fhp);
1507 goto out_nfserr;
1508 }
1509 if (created)
1510 *created = true;
1511
1512 nfsd_check_ignore_resizing(iap);
1513
1514 if (nfsd_create_is_exclusive(createmode)) {
1515
1516 iap->ia_valid = ATTR_MTIME|ATTR_ATIME
1517 | ATTR_MTIME_SET|ATTR_ATIME_SET;
1518
1519 iap->ia_mtime.tv_sec = v_mtime;
1520 iap->ia_atime.tv_sec = v_atime;
1521 iap->ia_mtime.tv_nsec = 0;
1522 iap->ia_atime.tv_nsec = 0;
1523 }
1524
1525 set_attr:
1526 err = nfsd_create_setattr(rqstp, resfhp, iap);
1527
1528
1529
1530
1531
1532 if (!err)
1533 err = nfserrno(commit_metadata(fhp));
1534
1535
1536
1537
1538 if (!err)
1539 err = fh_update(resfhp);
1540
1541 out:
1542 fh_unlock(fhp);
1543 if (dchild && !IS_ERR(dchild))
1544 dput(dchild);
1545 fh_drop_write(fhp);
1546 return err;
1547
1548 out_nfserr:
1549 err = nfserrno(host_err);
1550 goto out;
1551}
1552#endif
1553
1554
1555
1556
1557
1558
1559__be32
1560nfsd_readlink(struct svc_rqst *rqstp, struct svc_fh *fhp, char *buf, int *lenp)
1561{
1562 __be32 err;
1563 const char *link;
1564 struct path path;
1565 DEFINE_DELAYED_CALL(done);
1566 int len;
1567
1568 err = fh_verify(rqstp, fhp, S_IFLNK, NFSD_MAY_NOP);
1569 if (unlikely(err))
1570 return err;
1571
1572 path.mnt = fhp->fh_export->ex_path.mnt;
1573 path.dentry = fhp->fh_dentry;
1574
1575 if (unlikely(!d_is_symlink(path.dentry)))
1576 return nfserr_inval;
1577
1578 touch_atime(&path);
1579
1580 link = vfs_get_link(path.dentry, &done);
1581 if (IS_ERR(link))
1582 return nfserrno(PTR_ERR(link));
1583
1584 len = strlen(link);
1585 if (len < *lenp)
1586 *lenp = len;
1587 memcpy(buf, link, *lenp);
1588 do_delayed_call(&done);
1589 return 0;
1590}
1591
1592
1593
1594
1595
1596__be32
1597nfsd_symlink(struct svc_rqst *rqstp, struct svc_fh *fhp,
1598 char *fname, int flen,
1599 char *path,
1600 struct svc_fh *resfhp)
1601{
1602 struct dentry *dentry, *dnew;
1603 __be32 err, cerr;
1604 int host_err;
1605
1606 err = nfserr_noent;
1607 if (!flen || path[0] == '\0')
1608 goto out;
1609 err = nfserr_exist;
1610 if (isdotent(fname, flen))
1611 goto out;
1612
1613 err = fh_verify(rqstp, fhp, S_IFDIR, NFSD_MAY_CREATE);
1614 if (err)
1615 goto out;
1616
1617 host_err = fh_want_write(fhp);
1618 if (host_err)
1619 goto out_nfserr;
1620
1621 fh_lock(fhp);
1622 dentry = fhp->fh_dentry;
1623 dnew = lookup_one_len(fname, dentry, flen);
1624 host_err = PTR_ERR(dnew);
1625 if (IS_ERR(dnew))
1626 goto out_nfserr;
1627
1628 host_err = vfs_symlink(&init_user_ns, d_inode(dentry), dnew, path);
1629 err = nfserrno(host_err);
1630 fh_unlock(fhp);
1631 if (!err)
1632 err = nfserrno(commit_metadata(fhp));
1633
1634 fh_drop_write(fhp);
1635
1636 cerr = fh_compose(resfhp, fhp->fh_export, dnew, fhp);
1637 dput(dnew);
1638 if (err==0) err = cerr;
1639out:
1640 return err;
1641
1642out_nfserr:
1643 err = nfserrno(host_err);
1644 goto out;
1645}
1646
1647
1648
1649
1650
1651__be32
1652nfsd_link(struct svc_rqst *rqstp, struct svc_fh *ffhp,
1653 char *name, int len, struct svc_fh *tfhp)
1654{
1655 struct dentry *ddir, *dnew, *dold;
1656 struct inode *dirp;
1657 __be32 err;
1658 int host_err;
1659
1660 err = fh_verify(rqstp, ffhp, S_IFDIR, NFSD_MAY_CREATE);
1661 if (err)
1662 goto out;
1663 err = fh_verify(rqstp, tfhp, 0, NFSD_MAY_NOP);
1664 if (err)
1665 goto out;
1666 err = nfserr_isdir;
1667 if (d_is_dir(tfhp->fh_dentry))
1668 goto out;
1669 err = nfserr_perm;
1670 if (!len)
1671 goto out;
1672 err = nfserr_exist;
1673 if (isdotent(name, len))
1674 goto out;
1675
1676 host_err = fh_want_write(tfhp);
1677 if (host_err) {
1678 err = nfserrno(host_err);
1679 goto out;
1680 }
1681
1682 fh_lock_nested(ffhp, I_MUTEX_PARENT);
1683 ddir = ffhp->fh_dentry;
1684 dirp = d_inode(ddir);
1685
1686 dnew = lookup_one_len(name, ddir, len);
1687 host_err = PTR_ERR(dnew);
1688 if (IS_ERR(dnew))
1689 goto out_nfserr;
1690
1691 dold = tfhp->fh_dentry;
1692
1693 err = nfserr_noent;
1694 if (d_really_is_negative(dold))
1695 goto out_dput;
1696 host_err = vfs_link(dold, &init_user_ns, dirp, dnew, NULL);
1697 fh_unlock(ffhp);
1698 if (!host_err) {
1699 err = nfserrno(commit_metadata(ffhp));
1700 if (!err)
1701 err = nfserrno(commit_metadata(tfhp));
1702 } else {
1703 if (host_err == -EXDEV && rqstp->rq_vers == 2)
1704 err = nfserr_acces;
1705 else
1706 err = nfserrno(host_err);
1707 }
1708out_dput:
1709 dput(dnew);
1710out_unlock:
1711 fh_unlock(ffhp);
1712 fh_drop_write(tfhp);
1713out:
1714 return err;
1715
1716out_nfserr:
1717 err = nfserrno(host_err);
1718 goto out_unlock;
1719}
1720
1721static void
1722nfsd_close_cached_files(struct dentry *dentry)
1723{
1724 struct inode *inode = d_inode(dentry);
1725
1726 if (inode && S_ISREG(inode->i_mode))
1727 nfsd_file_close_inode_sync(inode);
1728}
1729
1730static bool
1731nfsd_has_cached_files(struct dentry *dentry)
1732{
1733 bool ret = false;
1734 struct inode *inode = d_inode(dentry);
1735
1736 if (inode && S_ISREG(inode->i_mode))
1737 ret = nfsd_file_is_cached(inode);
1738 return ret;
1739}
1740
1741
1742
1743
1744
1745__be32
1746nfsd_rename(struct svc_rqst *rqstp, struct svc_fh *ffhp, char *fname, int flen,
1747 struct svc_fh *tfhp, char *tname, int tlen)
1748{
1749 struct dentry *fdentry, *tdentry, *odentry, *ndentry, *trap;
1750 struct inode *fdir, *tdir;
1751 __be32 err;
1752 int host_err;
1753 bool close_cached = false;
1754
1755 err = fh_verify(rqstp, ffhp, S_IFDIR, NFSD_MAY_REMOVE);
1756 if (err)
1757 goto out;
1758 err = fh_verify(rqstp, tfhp, S_IFDIR, NFSD_MAY_CREATE);
1759 if (err)
1760 goto out;
1761
1762 fdentry = ffhp->fh_dentry;
1763 fdir = d_inode(fdentry);
1764
1765 tdentry = tfhp->fh_dentry;
1766 tdir = d_inode(tdentry);
1767
1768 err = nfserr_perm;
1769 if (!flen || isdotent(fname, flen) || !tlen || isdotent(tname, tlen))
1770 goto out;
1771
1772retry:
1773 host_err = fh_want_write(ffhp);
1774 if (host_err) {
1775 err = nfserrno(host_err);
1776 goto out;
1777 }
1778
1779
1780
1781 trap = lock_rename(tdentry, fdentry);
1782 ffhp->fh_locked = tfhp->fh_locked = true;
1783 fill_pre_wcc(ffhp);
1784 fill_pre_wcc(tfhp);
1785
1786 odentry = lookup_one_len(fname, fdentry, flen);
1787 host_err = PTR_ERR(odentry);
1788 if (IS_ERR(odentry))
1789 goto out_nfserr;
1790
1791 host_err = -ENOENT;
1792 if (d_really_is_negative(odentry))
1793 goto out_dput_old;
1794 host_err = -EINVAL;
1795 if (odentry == trap)
1796 goto out_dput_old;
1797
1798 ndentry = lookup_one_len(tname, tdentry, tlen);
1799 host_err = PTR_ERR(ndentry);
1800 if (IS_ERR(ndentry))
1801 goto out_dput_old;
1802 host_err = -ENOTEMPTY;
1803 if (ndentry == trap)
1804 goto out_dput_new;
1805
1806 host_err = -EXDEV;
1807 if (ffhp->fh_export->ex_path.mnt != tfhp->fh_export->ex_path.mnt)
1808 goto out_dput_new;
1809 if (ffhp->fh_export->ex_path.dentry != tfhp->fh_export->ex_path.dentry)
1810 goto out_dput_new;
1811
1812 if ((ndentry->d_sb->s_export_op->flags & EXPORT_OP_CLOSE_BEFORE_UNLINK) &&
1813 nfsd_has_cached_files(ndentry)) {
1814 close_cached = true;
1815 goto out_dput_old;
1816 } else {
1817 struct renamedata rd = {
1818 .old_mnt_userns = &init_user_ns,
1819 .old_dir = fdir,
1820 .old_dentry = odentry,
1821 .new_mnt_userns = &init_user_ns,
1822 .new_dir = tdir,
1823 .new_dentry = ndentry,
1824 };
1825 host_err = vfs_rename(&rd);
1826 if (!host_err) {
1827 host_err = commit_metadata(tfhp);
1828 if (!host_err)
1829 host_err = commit_metadata(ffhp);
1830 }
1831 }
1832 out_dput_new:
1833 dput(ndentry);
1834 out_dput_old:
1835 dput(odentry);
1836 out_nfserr:
1837 err = nfserrno(host_err);
1838
1839
1840
1841
1842
1843 if (!close_cached) {
1844 fill_post_wcc(ffhp);
1845 fill_post_wcc(tfhp);
1846 }
1847 unlock_rename(tdentry, fdentry);
1848 ffhp->fh_locked = tfhp->fh_locked = false;
1849 fh_drop_write(ffhp);
1850
1851
1852
1853
1854
1855
1856
1857 if (close_cached) {
1858 close_cached = false;
1859 nfsd_close_cached_files(ndentry);
1860 dput(ndentry);
1861 goto retry;
1862 }
1863out:
1864 return err;
1865}
1866
1867
1868
1869
1870
1871__be32
1872nfsd_unlink(struct svc_rqst *rqstp, struct svc_fh *fhp, int type,
1873 char *fname, int flen)
1874{
1875 struct dentry *dentry, *rdentry;
1876 struct inode *dirp;
1877 struct inode *rinode;
1878 __be32 err;
1879 int host_err;
1880
1881 err = nfserr_acces;
1882 if (!flen || isdotent(fname, flen))
1883 goto out;
1884 err = fh_verify(rqstp, fhp, S_IFDIR, NFSD_MAY_REMOVE);
1885 if (err)
1886 goto out;
1887
1888 host_err = fh_want_write(fhp);
1889 if (host_err)
1890 goto out_nfserr;
1891
1892 fh_lock_nested(fhp, I_MUTEX_PARENT);
1893 dentry = fhp->fh_dentry;
1894 dirp = d_inode(dentry);
1895
1896 rdentry = lookup_one_len(fname, dentry, flen);
1897 host_err = PTR_ERR(rdentry);
1898 if (IS_ERR(rdentry))
1899 goto out_drop_write;
1900
1901 if (d_really_is_negative(rdentry)) {
1902 dput(rdentry);
1903 host_err = -ENOENT;
1904 goto out_drop_write;
1905 }
1906 rinode = d_inode(rdentry);
1907 ihold(rinode);
1908
1909 if (!type)
1910 type = d_inode(rdentry)->i_mode & S_IFMT;
1911
1912 if (type != S_IFDIR) {
1913 if (rdentry->d_sb->s_export_op->flags & EXPORT_OP_CLOSE_BEFORE_UNLINK)
1914 nfsd_close_cached_files(rdentry);
1915 host_err = vfs_unlink(&init_user_ns, dirp, rdentry, NULL);
1916 } else {
1917 host_err = vfs_rmdir(&init_user_ns, dirp, rdentry);
1918 }
1919
1920 fh_unlock(fhp);
1921 if (!host_err)
1922 host_err = commit_metadata(fhp);
1923 dput(rdentry);
1924 iput(rinode);
1925
1926out_drop_write:
1927 fh_drop_write(fhp);
1928out_nfserr:
1929 if (host_err == -EBUSY) {
1930
1931
1932
1933 if (nfsd_v4client(rqstp))
1934 err = nfserr_file_open;
1935 else
1936 err = nfserr_acces;
1937 } else {
1938 err = nfserrno(host_err);
1939 }
1940out:
1941 return err;
1942}
1943
1944
1945
1946
1947
1948
1949
1950
1951struct buffered_dirent {
1952 u64 ino;
1953 loff_t offset;
1954 int namlen;
1955 unsigned int d_type;
1956 char name[];
1957};
1958
1959struct readdir_data {
1960 struct dir_context ctx;
1961 char *dirent;
1962 size_t used;
1963 int full;
1964};
1965
1966static int nfsd_buffered_filldir(struct dir_context *ctx, const char *name,
1967 int namlen, loff_t offset, u64 ino,
1968 unsigned int d_type)
1969{
1970 struct readdir_data *buf =
1971 container_of(ctx, struct readdir_data, ctx);
1972 struct buffered_dirent *de = (void *)(buf->dirent + buf->used);
1973 unsigned int reclen;
1974
1975 reclen = ALIGN(sizeof(struct buffered_dirent) + namlen, sizeof(u64));
1976 if (buf->used + reclen > PAGE_SIZE) {
1977 buf->full = 1;
1978 return -EINVAL;
1979 }
1980
1981 de->namlen = namlen;
1982 de->offset = offset;
1983 de->ino = ino;
1984 de->d_type = d_type;
1985 memcpy(de->name, name, namlen);
1986 buf->used += reclen;
1987
1988 return 0;
1989}
1990
1991static __be32 nfsd_buffered_readdir(struct file *file, struct svc_fh *fhp,
1992 nfsd_filldir_t func, struct readdir_cd *cdp,
1993 loff_t *offsetp)
1994{
1995 struct buffered_dirent *de;
1996 int host_err;
1997 int size;
1998 loff_t offset;
1999 struct readdir_data buf = {
2000 .ctx.actor = nfsd_buffered_filldir,
2001 .dirent = (void *)__get_free_page(GFP_KERNEL)
2002 };
2003
2004 if (!buf.dirent)
2005 return nfserrno(-ENOMEM);
2006
2007 offset = *offsetp;
2008
2009 while (1) {
2010 unsigned int reclen;
2011
2012 cdp->err = nfserr_eof;
2013 buf.used = 0;
2014 buf.full = 0;
2015
2016 host_err = iterate_dir(file, &buf.ctx);
2017 if (buf.full)
2018 host_err = 0;
2019
2020 if (host_err < 0)
2021 break;
2022
2023 size = buf.used;
2024
2025 if (!size)
2026 break;
2027
2028 de = (struct buffered_dirent *)buf.dirent;
2029 while (size > 0) {
2030 offset = de->offset;
2031
2032 if (func(cdp, de->name, de->namlen, de->offset,
2033 de->ino, de->d_type))
2034 break;
2035
2036 if (cdp->err != nfs_ok)
2037 break;
2038
2039 trace_nfsd_dirent(fhp, de->ino, de->name, de->namlen);
2040
2041 reclen = ALIGN(sizeof(*de) + de->namlen,
2042 sizeof(u64));
2043 size -= reclen;
2044 de = (struct buffered_dirent *)((char *)de + reclen);
2045 }
2046 if (size > 0)
2047 break;
2048
2049 offset = vfs_llseek(file, 0, SEEK_CUR);
2050 }
2051
2052 free_page((unsigned long)(buf.dirent));
2053
2054 if (host_err)
2055 return nfserrno(host_err);
2056
2057 *offsetp = offset;
2058 return cdp->err;
2059}
2060
2061
2062
2063
2064
2065__be32
2066nfsd_readdir(struct svc_rqst *rqstp, struct svc_fh *fhp, loff_t *offsetp,
2067 struct readdir_cd *cdp, nfsd_filldir_t func)
2068{
2069 __be32 err;
2070 struct file *file;
2071 loff_t offset = *offsetp;
2072 int may_flags = NFSD_MAY_READ;
2073
2074
2075 if (rqstp->rq_vers > 2)
2076 may_flags |= NFSD_MAY_64BIT_COOKIE;
2077
2078 err = nfsd_open(rqstp, fhp, S_IFDIR, may_flags, &file);
2079 if (err)
2080 goto out;
2081
2082 offset = vfs_llseek(file, offset, SEEK_SET);
2083 if (offset < 0) {
2084 err = nfserrno((int)offset);
2085 goto out_close;
2086 }
2087
2088 err = nfsd_buffered_readdir(file, fhp, func, cdp, offsetp);
2089
2090 if (err == nfserr_eof || err == nfserr_toosmall)
2091 err = nfs_ok;
2092out_close:
2093 fput(file);
2094out:
2095 return err;
2096}
2097
2098
2099
2100
2101
2102__be32
2103nfsd_statfs(struct svc_rqst *rqstp, struct svc_fh *fhp, struct kstatfs *stat, int access)
2104{
2105 __be32 err;
2106
2107 err = fh_verify(rqstp, fhp, 0, NFSD_MAY_NOP | access);
2108 if (!err) {
2109 struct path path = {
2110 .mnt = fhp->fh_export->ex_path.mnt,
2111 .dentry = fhp->fh_dentry,
2112 };
2113 if (vfs_statfs(&path, stat))
2114 err = nfserr_io;
2115 }
2116 return err;
2117}
2118
2119static int exp_rdonly(struct svc_rqst *rqstp, struct svc_export *exp)
2120{
2121 return nfsexp_flags(rqstp, exp) & NFSEXP_READONLY;
2122}
2123
2124#ifdef CONFIG_NFSD_V4
2125
2126
2127
2128
2129
2130
2131
2132
2133
2134
2135
2136
2137
2138
2139
2140
2141
2142
2143
2144static __be32
2145nfsd_xattr_errno(int err)
2146{
2147 switch (err) {
2148 case -ENODATA:
2149 return nfserr_noxattr;
2150 case -E2BIG:
2151 return nfserr_xattr2big;
2152 case -ERANGE:
2153 return nfserr_toosmall;
2154 }
2155 return nfserrno(err);
2156}
2157
2158
2159
2160
2161
2162
2163
2164
2165__be32
2166nfsd_getxattr(struct svc_rqst *rqstp, struct svc_fh *fhp, char *name,
2167 void **bufp, int *lenp)
2168{
2169 ssize_t len;
2170 __be32 err;
2171 char *buf;
2172 struct inode *inode;
2173 struct dentry *dentry;
2174
2175 err = fh_verify(rqstp, fhp, 0, NFSD_MAY_READ);
2176 if (err)
2177 return err;
2178
2179 err = nfs_ok;
2180 dentry = fhp->fh_dentry;
2181 inode = d_inode(dentry);
2182
2183 inode_lock_shared(inode);
2184
2185 len = vfs_getxattr(&init_user_ns, dentry, name, NULL, 0);
2186
2187
2188
2189
2190 if (len == 0) {
2191 *bufp = NULL;
2192 *lenp = 0;
2193 goto out;
2194 }
2195
2196 if (len < 0) {
2197 err = nfsd_xattr_errno(len);
2198 goto out;
2199 }
2200
2201 if (len > *lenp) {
2202 err = nfserr_toosmall;
2203 goto out;
2204 }
2205
2206 buf = kvmalloc(len, GFP_KERNEL | GFP_NOFS);
2207 if (buf == NULL) {
2208 err = nfserr_jukebox;
2209 goto out;
2210 }
2211
2212 len = vfs_getxattr(&init_user_ns, dentry, name, buf, len);
2213 if (len <= 0) {
2214 kvfree(buf);
2215 buf = NULL;
2216 err = nfsd_xattr_errno(len);
2217 }
2218
2219 *lenp = len;
2220 *bufp = buf;
2221
2222out:
2223 inode_unlock_shared(inode);
2224
2225 return err;
2226}
2227
2228
2229
2230
2231
2232
2233
2234
2235
2236
2237
2238__be32
2239nfsd_listxattr(struct svc_rqst *rqstp, struct svc_fh *fhp, char **bufp,
2240 int *lenp)
2241{
2242 ssize_t len;
2243 __be32 err;
2244 char *buf;
2245 struct inode *inode;
2246 struct dentry *dentry;
2247
2248 err = fh_verify(rqstp, fhp, 0, NFSD_MAY_READ);
2249 if (err)
2250 return err;
2251
2252 dentry = fhp->fh_dentry;
2253 inode = d_inode(dentry);
2254 *lenp = 0;
2255
2256 inode_lock_shared(inode);
2257
2258 len = vfs_listxattr(dentry, NULL, 0);
2259 if (len <= 0) {
2260 err = nfsd_xattr_errno(len);
2261 goto out;
2262 }
2263
2264 if (len > XATTR_LIST_MAX) {
2265 err = nfserr_xattr2big;
2266 goto out;
2267 }
2268
2269
2270
2271
2272 buf = kvmalloc(len, GFP_KERNEL | GFP_NOFS);
2273 if (buf == NULL) {
2274 err = nfserr_jukebox;
2275 goto out;
2276 }
2277
2278 len = vfs_listxattr(dentry, buf, len);
2279 if (len <= 0) {
2280 kvfree(buf);
2281 err = nfsd_xattr_errno(len);
2282 goto out;
2283 }
2284
2285 *lenp = len;
2286 *bufp = buf;
2287
2288 err = nfs_ok;
2289out:
2290 inode_unlock_shared(inode);
2291
2292 return err;
2293}
2294
2295
2296
2297
2298
2299
2300
2301
2302
2303__be32
2304nfsd_removexattr(struct svc_rqst *rqstp, struct svc_fh *fhp, char *name)
2305{
2306 __be32 err;
2307 int ret;
2308
2309 err = fh_verify(rqstp, fhp, 0, NFSD_MAY_WRITE);
2310 if (err)
2311 return err;
2312
2313 ret = fh_want_write(fhp);
2314 if (ret)
2315 return nfserrno(ret);
2316
2317 fh_lock(fhp);
2318
2319 ret = __vfs_removexattr_locked(&init_user_ns, fhp->fh_dentry,
2320 name, NULL);
2321
2322 fh_unlock(fhp);
2323 fh_drop_write(fhp);
2324
2325 return nfsd_xattr_errno(ret);
2326}
2327
2328__be32
2329nfsd_setxattr(struct svc_rqst *rqstp, struct svc_fh *fhp, char *name,
2330 void *buf, u32 len, u32 flags)
2331{
2332 __be32 err;
2333 int ret;
2334
2335 err = fh_verify(rqstp, fhp, 0, NFSD_MAY_WRITE);
2336 if (err)
2337 return err;
2338
2339 ret = fh_want_write(fhp);
2340 if (ret)
2341 return nfserrno(ret);
2342 fh_lock(fhp);
2343
2344 ret = __vfs_setxattr_locked(&init_user_ns, fhp->fh_dentry, name, buf,
2345 len, flags, NULL);
2346
2347 fh_unlock(fhp);
2348 fh_drop_write(fhp);
2349
2350 return nfsd_xattr_errno(ret);
2351}
2352#endif
2353
2354
2355
2356
2357__be32
2358nfsd_permission(struct svc_rqst *rqstp, struct svc_export *exp,
2359 struct dentry *dentry, int acc)
2360{
2361 struct inode *inode = d_inode(dentry);
2362 int err;
2363
2364 if ((acc & NFSD_MAY_MASK) == NFSD_MAY_NOP)
2365 return 0;
2366#if 0
2367 dprintk("nfsd: permission 0x%x%s%s%s%s%s%s%s mode 0%o%s%s%s\n",
2368 acc,
2369 (acc & NFSD_MAY_READ)? " read" : "",
2370 (acc & NFSD_MAY_WRITE)? " write" : "",
2371 (acc & NFSD_MAY_EXEC)? " exec" : "",
2372 (acc & NFSD_MAY_SATTR)? " sattr" : "",
2373 (acc & NFSD_MAY_TRUNC)? " trunc" : "",
2374 (acc & NFSD_MAY_LOCK)? " lock" : "",
2375 (acc & NFSD_MAY_OWNER_OVERRIDE)? " owneroverride" : "",
2376 inode->i_mode,
2377 IS_IMMUTABLE(inode)? " immut" : "",
2378 IS_APPEND(inode)? " append" : "",
2379 __mnt_is_readonly(exp->ex_path.mnt)? " ro" : "");
2380 dprintk(" owner %d/%d user %d/%d\n",
2381 inode->i_uid, inode->i_gid, current_fsuid(), current_fsgid());
2382#endif
2383
2384
2385
2386
2387
2388 if (!(acc & NFSD_MAY_LOCAL_ACCESS))
2389 if (acc & (NFSD_MAY_WRITE | NFSD_MAY_SATTR | NFSD_MAY_TRUNC)) {
2390 if (exp_rdonly(rqstp, exp) ||
2391 __mnt_is_readonly(exp->ex_path.mnt))
2392 return nfserr_rofs;
2393 if ( IS_IMMUTABLE(inode))
2394 return nfserr_perm;
2395 }
2396 if ((acc & NFSD_MAY_TRUNC) && IS_APPEND(inode))
2397 return nfserr_perm;
2398
2399 if (acc & NFSD_MAY_LOCK) {
2400
2401
2402
2403
2404 if (exp->ex_flags & NFSEXP_NOAUTHNLM)
2405 return 0;
2406 else
2407 acc = NFSD_MAY_READ | NFSD_MAY_OWNER_OVERRIDE;
2408 }
2409
2410
2411
2412
2413
2414
2415
2416
2417
2418
2419
2420
2421
2422
2423 if ((acc & NFSD_MAY_OWNER_OVERRIDE) &&
2424 uid_eq(inode->i_uid, current_fsuid()))
2425 return 0;
2426
2427
2428 err = inode_permission(&init_user_ns, inode,
2429 acc & (MAY_READ | MAY_WRITE | MAY_EXEC));
2430
2431
2432 if (err == -EACCES && S_ISREG(inode->i_mode) &&
2433 (acc == (NFSD_MAY_READ | NFSD_MAY_OWNER_OVERRIDE) ||
2434 acc == (NFSD_MAY_READ | NFSD_MAY_READ_IF_EXEC)))
2435 err = inode_permission(&init_user_ns, inode, MAY_EXEC);
2436
2437 return err? nfserrno(err) : 0;
2438}
2439