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1/*
2 * Quota code necessary even when VFS quota support is not compiled
3 * into the kernel. The interesting stuff is over in dquot.c, here
4 * we have symbols for initial quotactl(2) handling, the sysctl(2)
5 * variables, etc - things needed even when quota support disabled.
6 */
7
8#include <linux/fs.h>
9#include <linux/namei.h>
10#include <linux/slab.h>
11#include <asm/current.h>
12#include <linux/uaccess.h>
13#include <linux/kernel.h>
14#include <linux/security.h>
15#include <linux/syscalls.h>
16#include <linux/capability.h>
17#include <linux/quotaops.h>
18#include <linux/types.h>
19#include <linux/writeback.h>
20
21static int check_quotactl_permission(struct super_block *sb, int type, int cmd,
22 qid_t id)
23{
24 switch (cmd) {
25 /* these commands do not require any special privilegues */
26 case Q_GETFMT:
27 case Q_SYNC:
28 case Q_GETINFO:
29 case Q_XGETQSTAT:
30 case Q_XGETQSTATV:
31 case Q_XQUOTASYNC:
32 break;
33 /* allow to query information for dquots we "own" */
34 case Q_GETQUOTA:
35 case Q_XGETQUOTA:
36 if ((type == USRQUOTA && uid_eq(current_euid(), make_kuid(current_user_ns(), id))) ||
37 (type == GRPQUOTA && in_egroup_p(make_kgid(current_user_ns(), id))))
38 break;
39 /*FALLTHROUGH*/
40 default:
41 if (!capable(CAP_SYS_ADMIN))
42 return -EPERM;
43 }
44
45 return security_quotactl(cmd, type, id, sb);
46}
47
48static void quota_sync_one(struct super_block *sb, void *arg)
49{
50 int type = *(int *)arg;
51
52 if (sb->s_qcop && sb->s_qcop->quota_sync &&
53 (sb->s_quota_types & (1 << type)))
54 sb->s_qcop->quota_sync(sb, type);
55}
56
57static int quota_sync_all(int type)
58{
59 int ret;
60
61 if (type >= MAXQUOTAS)
62 return -EINVAL;
63 ret = security_quotactl(Q_SYNC, type, 0, NULL);
64 if (!ret)
65 iterate_supers(quota_sync_one, &type);
66 return ret;
67}
68
69unsigned int qtype_enforce_flag(int type)
70{
71 switch (type) {
72 case USRQUOTA:
73 return FS_QUOTA_UDQ_ENFD;
74 case GRPQUOTA:
75 return FS_QUOTA_GDQ_ENFD;
76 case PRJQUOTA:
77 return FS_QUOTA_PDQ_ENFD;
78 }
79 return 0;
80}
81
82static int quota_quotaon(struct super_block *sb, int type, qid_t id,
83 const struct path *path)
84{
85 if (!sb->s_qcop->quota_on && !sb->s_qcop->quota_enable)
86 return -ENOSYS;
87 if (sb->s_qcop->quota_enable)
88 return sb->s_qcop->quota_enable(sb, qtype_enforce_flag(type));
89 if (IS_ERR(path))
90 return PTR_ERR(path);
91 return sb->s_qcop->quota_on(sb, type, id, path);
92}
93
94static int quota_quotaoff(struct super_block *sb, int type)
95{
96 if (!sb->s_qcop->quota_off && !sb->s_qcop->quota_disable)
97 return -ENOSYS;
98 if (sb->s_qcop->quota_disable)
99 return sb->s_qcop->quota_disable(sb, qtype_enforce_flag(type));
100 return sb->s_qcop->quota_off(sb, type);
101}
102
103static int quota_getfmt(struct super_block *sb, int type, void __user *addr)
104{
105 __u32 fmt;
106
107 if (!sb_has_quota_active(sb, type))
108 return -ESRCH;
109 fmt = sb_dqopt(sb)->info[type].dqi_format->qf_fmt_id;
110 if (copy_to_user(addr, &fmt, sizeof(fmt)))
111 return -EFAULT;
112 return 0;
113}
114
115static int quota_getinfo(struct super_block *sb, int type, void __user *addr)
116{
117 struct qc_state state;
118 struct qc_type_state *tstate;
119 struct if_dqinfo uinfo;
120 int ret;
121
122 /* This checks whether qc_state has enough entries... */
123 BUILD_BUG_ON(MAXQUOTAS > XQM_MAXQUOTAS);
124 if (!sb->s_qcop->get_state)
125 return -ENOSYS;
126 ret = sb->s_qcop->get_state(sb, &state);
127 if (ret)
128 return ret;
129 tstate = state.s_state + type;
130 if (!(tstate->flags & QCI_ACCT_ENABLED))
131 return -ESRCH;
132 memset(&uinfo, 0, sizeof(uinfo));
133 uinfo.dqi_bgrace = tstate->spc_timelimit;
134 uinfo.dqi_igrace = tstate->ino_timelimit;
135 if (tstate->flags & QCI_SYSFILE)
136 uinfo.dqi_flags |= DQF_SYS_FILE;
137 if (tstate->flags & QCI_ROOT_SQUASH)
138 uinfo.dqi_flags |= DQF_ROOT_SQUASH;
139 uinfo.dqi_valid = IIF_ALL;
140 if (copy_to_user(addr, &uinfo, sizeof(uinfo)))
141 return -EFAULT;
142 return 0;
143}
144
145static int quota_setinfo(struct super_block *sb, int type, void __user *addr)
146{
147 struct if_dqinfo info;
148 struct qc_info qinfo;
149
150 if (copy_from_user(&info, addr, sizeof(info)))
151 return -EFAULT;
152 if (!sb->s_qcop->set_info)
153 return -ENOSYS;
154 if (info.dqi_valid & ~(IIF_FLAGS | IIF_BGRACE | IIF_IGRACE))
155 return -EINVAL;
156 memset(&qinfo, 0, sizeof(qinfo));
157 if (info.dqi_valid & IIF_FLAGS) {
158 if (info.dqi_flags & ~DQF_SETINFO_MASK)
159 return -EINVAL;
160 if (info.dqi_flags & DQF_ROOT_SQUASH)
161 qinfo.i_flags |= QCI_ROOT_SQUASH;
162 qinfo.i_fieldmask |= QC_FLAGS;
163 }
164 if (info.dqi_valid & IIF_BGRACE) {
165 qinfo.i_spc_timelimit = info.dqi_bgrace;
166 qinfo.i_fieldmask |= QC_SPC_TIMER;
167 }
168 if (info.dqi_valid & IIF_IGRACE) {
169 qinfo.i_ino_timelimit = info.dqi_igrace;
170 qinfo.i_fieldmask |= QC_INO_TIMER;
171 }
172 return sb->s_qcop->set_info(sb, type, &qinfo);
173}
174
175static inline qsize_t qbtos(qsize_t blocks)
176{
177 return blocks << QIF_DQBLKSIZE_BITS;
178}
179
180static inline qsize_t stoqb(qsize_t space)
181{
182 return (space + QIF_DQBLKSIZE - 1) >> QIF_DQBLKSIZE_BITS;
183}
184
185static void copy_to_if_dqblk(struct if_dqblk *dst, struct qc_dqblk *src)
186{
187 memset(dst, 0, sizeof(*dst));
188 dst->dqb_bhardlimit = stoqb(src->d_spc_hardlimit);
189 dst->dqb_bsoftlimit = stoqb(src->d_spc_softlimit);
190 dst->dqb_curspace = src->d_space;
191 dst->dqb_ihardlimit = src->d_ino_hardlimit;
192 dst->dqb_isoftlimit = src->d_ino_softlimit;
193 dst->dqb_curinodes = src->d_ino_count;
194 dst->dqb_btime = src->d_spc_timer;
195 dst->dqb_itime = src->d_ino_timer;
196 dst->dqb_valid = QIF_ALL;
197}
198
199static int quota_getquota(struct super_block *sb, int type, qid_t id,
200 void __user *addr)
201{
202 struct kqid qid;
203 struct qc_dqblk fdq;
204 struct if_dqblk idq;
205 int ret;
206
207 if (!sb->s_qcop->get_dqblk)
208 return -ENOSYS;
209 qid = make_kqid(current_user_ns(), type, id);
210 if (!qid_has_mapping(sb->s_user_ns, qid))
211 return -EINVAL;
212 ret = sb->s_qcop->get_dqblk(sb, qid, &fdq);
213 if (ret)
214 return ret;
215 copy_to_if_dqblk(&idq, &fdq);
216 if (copy_to_user(addr, &idq, sizeof(idq)))
217 return -EFAULT;
218 return 0;
219}
220
221/*
222 * Return quota for next active quota >= this id, if any exists,
223 * otherwise return -ENOENT via ->get_nextdqblk
224 */
225static int quota_getnextquota(struct super_block *sb, int type, qid_t id,
226 void __user *addr)
227{
228 struct kqid qid;
229 struct qc_dqblk fdq;
230 struct if_nextdqblk idq;
231 int ret;
232
233 if (!sb->s_qcop->get_nextdqblk)
234 return -ENOSYS;
235 qid = make_kqid(current_user_ns(), type, id);
236 if (!qid_has_mapping(sb->s_user_ns, qid))
237 return -EINVAL;
238 ret = sb->s_qcop->get_nextdqblk(sb, &qid, &fdq);
239 if (ret)
240 return ret;
241 /* struct if_nextdqblk is a superset of struct if_dqblk */
242 copy_to_if_dqblk((struct if_dqblk *)&idq, &fdq);
243 idq.dqb_id = from_kqid(current_user_ns(), qid);
244 if (copy_to_user(addr, &idq, sizeof(idq)))
245 return -EFAULT;
246 return 0;
247}
248
249static void copy_from_if_dqblk(struct qc_dqblk *dst, struct if_dqblk *src)
250{
251 dst->d_spc_hardlimit = qbtos(src->dqb_bhardlimit);
252 dst->d_spc_softlimit = qbtos(src->dqb_bsoftlimit);
253 dst->d_space = src->dqb_curspace;
254 dst->d_ino_hardlimit = src->dqb_ihardlimit;
255 dst->d_ino_softlimit = src->dqb_isoftlimit;
256 dst->d_ino_count = src->dqb_curinodes;
257 dst->d_spc_timer = src->dqb_btime;
258 dst->d_ino_timer = src->dqb_itime;
259
260 dst->d_fieldmask = 0;
261 if (src->dqb_valid & QIF_BLIMITS)
262 dst->d_fieldmask |= QC_SPC_SOFT | QC_SPC_HARD;
263 if (src->dqb_valid & QIF_SPACE)
264 dst->d_fieldmask |= QC_SPACE;
265 if (src->dqb_valid & QIF_ILIMITS)
266 dst->d_fieldmask |= QC_INO_SOFT | QC_INO_HARD;
267 if (src->dqb_valid & QIF_INODES)
268 dst->d_fieldmask |= QC_INO_COUNT;
269 if (src->dqb_valid & QIF_BTIME)
270 dst->d_fieldmask |= QC_SPC_TIMER;
271 if (src->dqb_valid & QIF_ITIME)
272 dst->d_fieldmask |= QC_INO_TIMER;
273}
274
275static int quota_setquota(struct super_block *sb, int type, qid_t id,
276 void __user *addr)
277{
278 struct qc_dqblk fdq;
279 struct if_dqblk idq;
280 struct kqid qid;
281
282 if (copy_from_user(&idq, addr, sizeof(idq)))
283 return -EFAULT;
284 if (!sb->s_qcop->set_dqblk)
285 return -ENOSYS;
286 qid = make_kqid(current_user_ns(), type, id);
287 if (!qid_has_mapping(sb->s_user_ns, qid))
288 return -EINVAL;
289 copy_from_if_dqblk(&fdq, &idq);
290 return sb->s_qcop->set_dqblk(sb, qid, &fdq);
291}
292
293static int quota_enable(struct super_block *sb, void __user *addr)
294{
295 __u32 flags;
296
297 if (copy_from_user(&flags, addr, sizeof(flags)))
298 return -EFAULT;
299 if (!sb->s_qcop->quota_enable)
300 return -ENOSYS;
301 return sb->s_qcop->quota_enable(sb, flags);
302}
303
304static int quota_disable(struct super_block *sb, void __user *addr)
305{
306 __u32 flags;
307
308 if (copy_from_user(&flags, addr, sizeof(flags)))
309 return -EFAULT;
310 if (!sb->s_qcop->quota_disable)
311 return -ENOSYS;
312 return sb->s_qcop->quota_disable(sb, flags);
313}
314
315static int quota_state_to_flags(struct qc_state *state)
316{
317 int flags = 0;
318
319 if (state->s_state[USRQUOTA].flags & QCI_ACCT_ENABLED)
320 flags |= FS_QUOTA_UDQ_ACCT;
321 if (state->s_state[USRQUOTA].flags & QCI_LIMITS_ENFORCED)
322 flags |= FS_QUOTA_UDQ_ENFD;
323 if (state->s_state[GRPQUOTA].flags & QCI_ACCT_ENABLED)
324 flags |= FS_QUOTA_GDQ_ACCT;
325 if (state->s_state[GRPQUOTA].flags & QCI_LIMITS_ENFORCED)
326 flags |= FS_QUOTA_GDQ_ENFD;
327 if (state->s_state[PRJQUOTA].flags & QCI_ACCT_ENABLED)
328 flags |= FS_QUOTA_PDQ_ACCT;
329 if (state->s_state[PRJQUOTA].flags & QCI_LIMITS_ENFORCED)
330 flags |= FS_QUOTA_PDQ_ENFD;
331 return flags;
332}
333
334static int quota_getstate(struct super_block *sb, struct fs_quota_stat *fqs)
335{
336 int type;
337 struct qc_state state;
338 int ret;
339
340 memset(&state, 0, sizeof (struct qc_state));
341 ret = sb->s_qcop->get_state(sb, &state);
342 if (ret < 0)
343 return ret;
344
345 memset(fqs, 0, sizeof(*fqs));
346 fqs->qs_version = FS_QSTAT_VERSION;
347 fqs->qs_flags = quota_state_to_flags(&state);
348 /* No quota enabled? */
349 if (!fqs->qs_flags)
350 return -ENOSYS;
351 fqs->qs_incoredqs = state.s_incoredqs;
352 /*
353 * GETXSTATE quotactl has space for just one set of time limits so
354 * report them for the first enabled quota type
355 */
356 for (type = 0; type < XQM_MAXQUOTAS; type++)
357 if (state.s_state[type].flags & QCI_ACCT_ENABLED)
358 break;
359 BUG_ON(type == XQM_MAXQUOTAS);
360 fqs->qs_btimelimit = state.s_state[type].spc_timelimit;
361 fqs->qs_itimelimit = state.s_state[type].ino_timelimit;
362 fqs->qs_rtbtimelimit = state.s_state[type].rt_spc_timelimit;
363 fqs->qs_bwarnlimit = state.s_state[type].spc_warnlimit;
364 fqs->qs_iwarnlimit = state.s_state[type].ino_warnlimit;
365
366 /* Inodes may be allocated even if inactive; copy out if present */
367 if (state.s_state[USRQUOTA].ino) {
368 fqs->qs_uquota.qfs_ino = state.s_state[USRQUOTA].ino;
369 fqs->qs_uquota.qfs_nblks = state.s_state[USRQUOTA].blocks;
370 fqs->qs_uquota.qfs_nextents = state.s_state[USRQUOTA].nextents;
371 }
372 if (state.s_state[GRPQUOTA].ino) {
373 fqs->qs_gquota.qfs_ino = state.s_state[GRPQUOTA].ino;
374 fqs->qs_gquota.qfs_nblks = state.s_state[GRPQUOTA].blocks;
375 fqs->qs_gquota.qfs_nextents = state.s_state[GRPQUOTA].nextents;
376 }
377 if (state.s_state[PRJQUOTA].ino) {
378 /*
379 * Q_XGETQSTAT doesn't have room for both group and project
380 * quotas. So, allow the project quota values to be copied out
381 * only if there is no group quota information available.
382 */
383 if (!(state.s_state[GRPQUOTA].flags & QCI_ACCT_ENABLED)) {
384 fqs->qs_gquota.qfs_ino = state.s_state[PRJQUOTA].ino;
385 fqs->qs_gquota.qfs_nblks =
386 state.s_state[PRJQUOTA].blocks;
387 fqs->qs_gquota.qfs_nextents =
388 state.s_state[PRJQUOTA].nextents;
389 }
390 }
391 return 0;
392}
393
394static int quota_getxstate(struct super_block *sb, void __user *addr)
395{
396 struct fs_quota_stat fqs;
397 int ret;
398
399 if (!sb->s_qcop->get_state)
400 return -ENOSYS;
401 ret = quota_getstate(sb, &fqs);
402 if (!ret && copy_to_user(addr, &fqs, sizeof(fqs)))
403 return -EFAULT;
404 return ret;
405}
406
407static int quota_getstatev(struct super_block *sb, struct fs_quota_statv *fqs)
408{
409 int type;
410 struct qc_state state;
411 int ret;
412
413 memset(&state, 0, sizeof (struct qc_state));
414 ret = sb->s_qcop->get_state(sb, &state);
415 if (ret < 0)
416 return ret;
417
418 memset(fqs, 0, sizeof(*fqs));
419 fqs->qs_version = FS_QSTAT_VERSION;
420 fqs->qs_flags = quota_state_to_flags(&state);
421 /* No quota enabled? */
422 if (!fqs->qs_flags)
423 return -ENOSYS;
424 fqs->qs_incoredqs = state.s_incoredqs;
425 /*
426 * GETXSTATV quotactl has space for just one set of time limits so
427 * report them for the first enabled quota type
428 */
429 for (type = 0; type < XQM_MAXQUOTAS; type++)
430 if (state.s_state[type].flags & QCI_ACCT_ENABLED)
431 break;
432 BUG_ON(type == XQM_MAXQUOTAS);
433 fqs->qs_btimelimit = state.s_state[type].spc_timelimit;
434 fqs->qs_itimelimit = state.s_state[type].ino_timelimit;
435 fqs->qs_rtbtimelimit = state.s_state[type].rt_spc_timelimit;
436 fqs->qs_bwarnlimit = state.s_state[type].spc_warnlimit;
437 fqs->qs_iwarnlimit = state.s_state[type].ino_warnlimit;
438
439 /* Inodes may be allocated even if inactive; copy out if present */
440 if (state.s_state[USRQUOTA].ino) {
441 fqs->qs_uquota.qfs_ino = state.s_state[USRQUOTA].ino;
442 fqs->qs_uquota.qfs_nblks = state.s_state[USRQUOTA].blocks;
443 fqs->qs_uquota.qfs_nextents = state.s_state[USRQUOTA].nextents;
444 }
445 if (state.s_state[GRPQUOTA].ino) {
446 fqs->qs_gquota.qfs_ino = state.s_state[GRPQUOTA].ino;
447 fqs->qs_gquota.qfs_nblks = state.s_state[GRPQUOTA].blocks;
448 fqs->qs_gquota.qfs_nextents = state.s_state[GRPQUOTA].nextents;
449 }
450 if (state.s_state[PRJQUOTA].ino) {
451 fqs->qs_pquota.qfs_ino = state.s_state[PRJQUOTA].ino;
452 fqs->qs_pquota.qfs_nblks = state.s_state[PRJQUOTA].blocks;
453 fqs->qs_pquota.qfs_nextents = state.s_state[PRJQUOTA].nextents;
454 }
455 return 0;
456}
457
458static int quota_getxstatev(struct super_block *sb, void __user *addr)
459{
460 struct fs_quota_statv fqs;
461 int ret;
462
463 if (!sb->s_qcop->get_state)
464 return -ENOSYS;
465
466 memset(&fqs, 0, sizeof(fqs));
467 if (copy_from_user(&fqs, addr, 1)) /* Just read qs_version */
468 return -EFAULT;
469
470 /* If this kernel doesn't support user specified version, fail */
471 switch (fqs.qs_version) {
472 case FS_QSTATV_VERSION1:
473 break;
474 default:
475 return -EINVAL;
476 }
477 ret = quota_getstatev(sb, &fqs);
478 if (!ret && copy_to_user(addr, &fqs, sizeof(fqs)))
479 return -EFAULT;
480 return ret;
481}
482
483/*
484 * XFS defines BBTOB and BTOBB macros inside fs/xfs/ and we cannot move them
485 * out of there as xfsprogs rely on definitions being in that header file. So
486 * just define same functions here for quota purposes.
487 */
488#define XFS_BB_SHIFT 9
489
490static inline u64 quota_bbtob(u64 blocks)
491{
492 return blocks << XFS_BB_SHIFT;
493}
494
495static inline u64 quota_btobb(u64 bytes)
496{
497 return (bytes + (1 << XFS_BB_SHIFT) - 1) >> XFS_BB_SHIFT;
498}
499
500static void copy_from_xfs_dqblk(struct qc_dqblk *dst, struct fs_disk_quota *src)
501{
502 dst->d_spc_hardlimit = quota_bbtob(src->d_blk_hardlimit);
503 dst->d_spc_softlimit = quota_bbtob(src->d_blk_softlimit);
504 dst->d_ino_hardlimit = src->d_ino_hardlimit;
505 dst->d_ino_softlimit = src->d_ino_softlimit;
506 dst->d_space = quota_bbtob(src->d_bcount);
507 dst->d_ino_count = src->d_icount;
508 dst->d_ino_timer = src->d_itimer;
509 dst->d_spc_timer = src->d_btimer;
510 dst->d_ino_warns = src->d_iwarns;
511 dst->d_spc_warns = src->d_bwarns;
512 dst->d_rt_spc_hardlimit = quota_bbtob(src->d_rtb_hardlimit);
513 dst->d_rt_spc_softlimit = quota_bbtob(src->d_rtb_softlimit);
514 dst->d_rt_space = quota_bbtob(src->d_rtbcount);
515 dst->d_rt_spc_timer = src->d_rtbtimer;
516 dst->d_rt_spc_warns = src->d_rtbwarns;
517 dst->d_fieldmask = 0;
518 if (src->d_fieldmask & FS_DQ_ISOFT)
519 dst->d_fieldmask |= QC_INO_SOFT;
520 if (src->d_fieldmask & FS_DQ_IHARD)
521 dst->d_fieldmask |= QC_INO_HARD;
522 if (src->d_fieldmask & FS_DQ_BSOFT)
523 dst->d_fieldmask |= QC_SPC_SOFT;
524 if (src->d_fieldmask & FS_DQ_BHARD)
525 dst->d_fieldmask |= QC_SPC_HARD;
526 if (src->d_fieldmask & FS_DQ_RTBSOFT)
527 dst->d_fieldmask |= QC_RT_SPC_SOFT;
528 if (src->d_fieldmask & FS_DQ_RTBHARD)
529 dst->d_fieldmask |= QC_RT_SPC_HARD;
530 if (src->d_fieldmask & FS_DQ_BTIMER)
531 dst->d_fieldmask |= QC_SPC_TIMER;
532 if (src->d_fieldmask & FS_DQ_ITIMER)
533 dst->d_fieldmask |= QC_INO_TIMER;
534 if (src->d_fieldmask & FS_DQ_RTBTIMER)
535 dst->d_fieldmask |= QC_RT_SPC_TIMER;
536 if (src->d_fieldmask & FS_DQ_BWARNS)
537 dst->d_fieldmask |= QC_SPC_WARNS;
538 if (src->d_fieldmask & FS_DQ_IWARNS)
539 dst->d_fieldmask |= QC_INO_WARNS;
540 if (src->d_fieldmask & FS_DQ_RTBWARNS)
541 dst->d_fieldmask |= QC_RT_SPC_WARNS;
542 if (src->d_fieldmask & FS_DQ_BCOUNT)
543 dst->d_fieldmask |= QC_SPACE;
544 if (src->d_fieldmask & FS_DQ_ICOUNT)
545 dst->d_fieldmask |= QC_INO_COUNT;
546 if (src->d_fieldmask & FS_DQ_RTBCOUNT)
547 dst->d_fieldmask |= QC_RT_SPACE;
548}
549
550static void copy_qcinfo_from_xfs_dqblk(struct qc_info *dst,
551 struct fs_disk_quota *src)
552{
553 memset(dst, 0, sizeof(*dst));
554 dst->i_spc_timelimit = src->d_btimer;
555 dst->i_ino_timelimit = src->d_itimer;
556 dst->i_rt_spc_timelimit = src->d_rtbtimer;
557 dst->i_ino_warnlimit = src->d_iwarns;
558 dst->i_spc_warnlimit = src->d_bwarns;
559 dst->i_rt_spc_warnlimit = src->d_rtbwarns;
560 if (src->d_fieldmask & FS_DQ_BWARNS)
561 dst->i_fieldmask |= QC_SPC_WARNS;
562 if (src->d_fieldmask & FS_DQ_IWARNS)
563 dst->i_fieldmask |= QC_INO_WARNS;
564 if (src->d_fieldmask & FS_DQ_RTBWARNS)
565 dst->i_fieldmask |= QC_RT_SPC_WARNS;
566 if (src->d_fieldmask & FS_DQ_BTIMER)
567 dst->i_fieldmask |= QC_SPC_TIMER;
568 if (src->d_fieldmask & FS_DQ_ITIMER)
569 dst->i_fieldmask |= QC_INO_TIMER;
570 if (src->d_fieldmask & FS_DQ_RTBTIMER)
571 dst->i_fieldmask |= QC_RT_SPC_TIMER;
572}
573
574static int quota_setxquota(struct super_block *sb, int type, qid_t id,
575 void __user *addr)
576{
577 struct fs_disk_quota fdq;
578 struct qc_dqblk qdq;
579 struct kqid qid;
580
581 if (copy_from_user(&fdq, addr, sizeof(fdq)))
582 return -EFAULT;
583 if (!sb->s_qcop->set_dqblk)
584 return -ENOSYS;
585 qid = make_kqid(current_user_ns(), type, id);
586 if (!qid_has_mapping(sb->s_user_ns, qid))
587 return -EINVAL;
588 /* Are we actually setting timer / warning limits for all users? */
589 if (from_kqid(sb->s_user_ns, qid) == 0 &&
590 fdq.d_fieldmask & (FS_DQ_WARNS_MASK | FS_DQ_TIMER_MASK)) {
591 struct qc_info qinfo;
592 int ret;
593
594 if (!sb->s_qcop->set_info)
595 return -EINVAL;
596 copy_qcinfo_from_xfs_dqblk(&qinfo, &fdq);
597 ret = sb->s_qcop->set_info(sb, type, &qinfo);
598 if (ret)
599 return ret;
600 /* These are already done */
601 fdq.d_fieldmask &= ~(FS_DQ_WARNS_MASK | FS_DQ_TIMER_MASK);
602 }
603 copy_from_xfs_dqblk(&qdq, &fdq);
604 return sb->s_qcop->set_dqblk(sb, qid, &qdq);
605}
606
607static void copy_to_xfs_dqblk(struct fs_disk_quota *dst, struct qc_dqblk *src,
608 int type, qid_t id)
609{
610 memset(dst, 0, sizeof(*dst));
611 dst->d_version = FS_DQUOT_VERSION;
612 dst->d_id = id;
613 if (type == USRQUOTA)
614 dst->d_flags = FS_USER_QUOTA;
615 else if (type == PRJQUOTA)
616 dst->d_flags = FS_PROJ_QUOTA;
617 else
618 dst->d_flags = FS_GROUP_QUOTA;
619 dst->d_blk_hardlimit = quota_btobb(src->d_spc_hardlimit);
620 dst->d_blk_softlimit = quota_btobb(src->d_spc_softlimit);
621 dst->d_ino_hardlimit = src->d_ino_hardlimit;
622 dst->d_ino_softlimit = src->d_ino_softlimit;
623 dst->d_bcount = quota_btobb(src->d_space);
624 dst->d_icount = src->d_ino_count;
625 dst->d_itimer = src->d_ino_timer;
626 dst->d_btimer = src->d_spc_timer;
627 dst->d_iwarns = src->d_ino_warns;
628 dst->d_bwarns = src->d_spc_warns;
629 dst->d_rtb_hardlimit = quota_btobb(src->d_rt_spc_hardlimit);
630 dst->d_rtb_softlimit = quota_btobb(src->d_rt_spc_softlimit);
631 dst->d_rtbcount = quota_btobb(src->d_rt_space);
632 dst->d_rtbtimer = src->d_rt_spc_timer;
633 dst->d_rtbwarns = src->d_rt_spc_warns;
634}
635
636static int quota_getxquota(struct super_block *sb, int type, qid_t id,
637 void __user *addr)
638{
639 struct fs_disk_quota fdq;
640 struct qc_dqblk qdq;
641 struct kqid qid;
642 int ret;
643
644 if (!sb->s_qcop->get_dqblk)
645 return -ENOSYS;
646 qid = make_kqid(current_user_ns(), type, id);
647 if (!qid_has_mapping(sb->s_user_ns, qid))
648 return -EINVAL;
649 ret = sb->s_qcop->get_dqblk(sb, qid, &qdq);
650 if (ret)
651 return ret;
652 copy_to_xfs_dqblk(&fdq, &qdq, type, id);
653 if (copy_to_user(addr, &fdq, sizeof(fdq)))
654 return -EFAULT;
655 return ret;
656}
657
658/*
659 * Return quota for next active quota >= this id, if any exists,
660 * otherwise return -ENOENT via ->get_nextdqblk.
661 */
662static int quota_getnextxquota(struct super_block *sb, int type, qid_t id,
663 void __user *addr)
664{
665 struct fs_disk_quota fdq;
666 struct qc_dqblk qdq;
667 struct kqid qid;
668 qid_t id_out;
669 int ret;
670
671 if (!sb->s_qcop->get_nextdqblk)
672 return -ENOSYS;
673 qid = make_kqid(current_user_ns(), type, id);
674 if (!qid_has_mapping(sb->s_user_ns, qid))
675 return -EINVAL;
676 ret = sb->s_qcop->get_nextdqblk(sb, &qid, &qdq);
677 if (ret)
678 return ret;
679 id_out = from_kqid(current_user_ns(), qid);
680 copy_to_xfs_dqblk(&fdq, &qdq, type, id_out);
681 if (copy_to_user(addr, &fdq, sizeof(fdq)))
682 return -EFAULT;
683 return ret;
684}
685
686static int quota_rmxquota(struct super_block *sb, void __user *addr)
687{
688 __u32 flags;
689
690 if (copy_from_user(&flags, addr, sizeof(flags)))
691 return -EFAULT;
692 if (!sb->s_qcop->rm_xquota)
693 return -ENOSYS;
694 return sb->s_qcop->rm_xquota(sb, flags);
695}
696
697/* Copy parameters and call proper function */
698static int do_quotactl(struct super_block *sb, int type, int cmd, qid_t id,
699 void __user *addr, const struct path *path)
700{
701 int ret;
702
703 if (type >= (XQM_COMMAND(cmd) ? XQM_MAXQUOTAS : MAXQUOTAS))
704 return -EINVAL;
705 /*
706 * Quota not supported on this fs? Check this before s_quota_types
707 * since they needn't be set if quota is not supported at all.
708 */
709 if (!sb->s_qcop)
710 return -ENOSYS;
711 if (!(sb->s_quota_types & (1 << type)))
712 return -EINVAL;
713
714 ret = check_quotactl_permission(sb, type, cmd, id);
715 if (ret < 0)
716 return ret;
717
718 switch (cmd) {
719 case Q_QUOTAON:
720 return quota_quotaon(sb, type, id, path);
721 case Q_QUOTAOFF:
722 return quota_quotaoff(sb, type);
723 case Q_GETFMT:
724 return quota_getfmt(sb, type, addr);
725 case Q_GETINFO:
726 return quota_getinfo(sb, type, addr);
727 case Q_SETINFO:
728 return quota_setinfo(sb, type, addr);
729 case Q_GETQUOTA:
730 return quota_getquota(sb, type, id, addr);
731 case Q_GETNEXTQUOTA:
732 return quota_getnextquota(sb, type, id, addr);
733 case Q_SETQUOTA:
734 return quota_setquota(sb, type, id, addr);
735 case Q_SYNC:
736 if (!sb->s_qcop->quota_sync)
737 return -ENOSYS;
738 return sb->s_qcop->quota_sync(sb, type);
739 case Q_XQUOTAON:
740 return quota_enable(sb, addr);
741 case Q_XQUOTAOFF:
742 return quota_disable(sb, addr);
743 case Q_XQUOTARM:
744 return quota_rmxquota(sb, addr);
745 case Q_XGETQSTAT:
746 return quota_getxstate(sb, addr);
747 case Q_XGETQSTATV:
748 return quota_getxstatev(sb, addr);
749 case Q_XSETQLIM:
750 return quota_setxquota(sb, type, id, addr);
751 case Q_XGETQUOTA:
752 return quota_getxquota(sb, type, id, addr);
753 case Q_XGETNEXTQUOTA:
754 return quota_getnextxquota(sb, type, id, addr);
755 case Q_XQUOTASYNC:
756 if (sb->s_flags & MS_RDONLY)
757 return -EROFS;
758 /* XFS quotas are fully coherent now, making this call a noop */
759 return 0;
760 default:
761 return -EINVAL;
762 }
763}
764
765#ifdef CONFIG_BLOCK
766
767/* Return 1 if 'cmd' will block on frozen filesystem */
768static int quotactl_cmd_write(int cmd)
769{
770 /*
771 * We cannot allow Q_GETQUOTA and Q_GETNEXTQUOTA without write access
772 * as dquot_acquire() may allocate space for new structure and OCFS2
773 * needs to increment on-disk use count.
774 */
775 switch (cmd) {
776 case Q_GETFMT:
777 case Q_GETINFO:
778 case Q_SYNC:
779 case Q_XGETQSTAT:
780 case Q_XGETQSTATV:
781 case Q_XGETQUOTA:
782 case Q_XGETNEXTQUOTA:
783 case Q_XQUOTASYNC:
784 return 0;
785 }
786 return 1;
787}
788#endif /* CONFIG_BLOCK */
789
790/* Return true if quotactl command is manipulating quota on/off state */
791static bool quotactl_cmd_onoff(int cmd)
792{
793 return (cmd == Q_QUOTAON) || (cmd == Q_QUOTAOFF);
794}
795
796/*
797 * look up a superblock on which quota ops will be performed
798 * - use the name of a block device to find the superblock thereon
799 */
800static struct super_block *quotactl_block(const char __user *special, int cmd)
801{
802#ifdef CONFIG_BLOCK
803 struct block_device *bdev;
804 struct super_block *sb;
805 struct filename *tmp = getname(special);
806
807 if (IS_ERR(tmp))
808 return ERR_CAST(tmp);
809 bdev = lookup_bdev(tmp->name);
810 putname(tmp);
811 if (IS_ERR(bdev))
812 return ERR_CAST(bdev);
813 if (quotactl_cmd_onoff(cmd))
814 sb = get_super_exclusive_thawed(bdev);
815 else if (quotactl_cmd_write(cmd))
816 sb = get_super_thawed(bdev);
817 else
818 sb = get_super(bdev);
819 bdput(bdev);
820 if (!sb)
821 return ERR_PTR(-ENODEV);
822
823 return sb;
824#else
825 return ERR_PTR(-ENODEV);
826#endif
827}
828
829/*
830 * This is the system call interface. This communicates with
831 * the user-level programs. Currently this only supports diskquota
832 * calls. Maybe we need to add the process quotas etc. in the future,
833 * but we probably should use rlimits for that.
834 */
835SYSCALL_DEFINE4(quotactl, unsigned int, cmd, const char __user *, special,
836 qid_t, id, void __user *, addr)
837{
838 uint cmds, type;
839 struct super_block *sb = NULL;
840 struct path path, *pathp = NULL;
841 int ret;
842
843 cmds = cmd >> SUBCMDSHIFT;
844 type = cmd & SUBCMDMASK;
845
846 /*
847 * As a special case Q_SYNC can be called without a specific device.
848 * It will iterate all superblocks that have quota enabled and call
849 * the sync action on each of them.
850 */
851 if (!special) {
852 if (cmds == Q_SYNC)
853 return quota_sync_all(type);
854 return -ENODEV;
855 }
856
857 /*
858 * Path for quotaon has to be resolved before grabbing superblock
859 * because that gets s_umount sem which is also possibly needed by path
860 * resolution (think about autofs) and thus deadlocks could arise.
861 */
862 if (cmds == Q_QUOTAON) {
863 ret = user_path_at(AT_FDCWD, addr, LOOKUP_FOLLOW|LOOKUP_AUTOMOUNT, &path);
864 if (ret)
865 pathp = ERR_PTR(ret);
866 else
867 pathp = &path;
868 }
869
870 sb = quotactl_block(special, cmds);
871 if (IS_ERR(sb)) {
872 ret = PTR_ERR(sb);
873 goto out;
874 }
875
876 ret = do_quotactl(sb, type, cmds, id, addr, pathp);
877
878 if (!quotactl_cmd_onoff(cmds))
879 drop_super(sb);
880 else
881 drop_super_exclusive(sb);
882out:
883 if (pathp && !IS_ERR(pathp))
884 path_put(pathp);
885 return ret;
886}
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Quota code necessary even when VFS quota support is not compiled
4 * into the kernel. The interesting stuff is over in dquot.c, here
5 * we have symbols for initial quotactl(2) handling, the sysctl(2)
6 * variables, etc - things needed even when quota support disabled.
7 */
8
9#include <linux/fs.h>
10#include <linux/namei.h>
11#include <linux/slab.h>
12#include <asm/current.h>
13#include <linux/blkdev.h>
14#include <linux/uaccess.h>
15#include <linux/kernel.h>
16#include <linux/security.h>
17#include <linux/syscalls.h>
18#include <linux/capability.h>
19#include <linux/quotaops.h>
20#include <linux/types.h>
21#include <linux/mount.h>
22#include <linux/writeback.h>
23#include <linux/nospec.h>
24#include "compat.h"
25#include "../internal.h"
26
27static int check_quotactl_permission(struct super_block *sb, int type, int cmd,
28 qid_t id)
29{
30 switch (cmd) {
31 /* these commands do not require any special privilegues */
32 case Q_GETFMT:
33 case Q_SYNC:
34 case Q_GETINFO:
35 case Q_XGETQSTAT:
36 case Q_XGETQSTATV:
37 case Q_XQUOTASYNC:
38 break;
39 /* allow to query information for dquots we "own" */
40 case Q_GETQUOTA:
41 case Q_XGETQUOTA:
42 if ((type == USRQUOTA && uid_eq(current_euid(), make_kuid(current_user_ns(), id))) ||
43 (type == GRPQUOTA && in_egroup_p(make_kgid(current_user_ns(), id))))
44 break;
45 fallthrough;
46 default:
47 if (!capable(CAP_SYS_ADMIN))
48 return -EPERM;
49 }
50
51 return security_quotactl(cmd, type, id, sb);
52}
53
54static void quota_sync_one(struct super_block *sb, void *arg)
55{
56 int type = *(int *)arg;
57
58 if (sb->s_qcop && sb->s_qcop->quota_sync &&
59 (sb->s_quota_types & (1 << type)))
60 sb->s_qcop->quota_sync(sb, type);
61}
62
63static int quota_sync_all(int type)
64{
65 int ret;
66
67 ret = security_quotactl(Q_SYNC, type, 0, NULL);
68 if (!ret)
69 iterate_supers(quota_sync_one, &type);
70 return ret;
71}
72
73unsigned int qtype_enforce_flag(int type)
74{
75 switch (type) {
76 case USRQUOTA:
77 return FS_QUOTA_UDQ_ENFD;
78 case GRPQUOTA:
79 return FS_QUOTA_GDQ_ENFD;
80 case PRJQUOTA:
81 return FS_QUOTA_PDQ_ENFD;
82 }
83 return 0;
84}
85
86static int quota_quotaon(struct super_block *sb, int type, qid_t id,
87 const struct path *path)
88{
89 if (!sb->s_qcop->quota_on && !sb->s_qcop->quota_enable)
90 return -ENOSYS;
91 if (sb->s_qcop->quota_enable)
92 return sb->s_qcop->quota_enable(sb, qtype_enforce_flag(type));
93 if (IS_ERR(path))
94 return PTR_ERR(path);
95 return sb->s_qcop->quota_on(sb, type, id, path);
96}
97
98static int quota_quotaoff(struct super_block *sb, int type)
99{
100 if (!sb->s_qcop->quota_off && !sb->s_qcop->quota_disable)
101 return -ENOSYS;
102 if (sb->s_qcop->quota_disable)
103 return sb->s_qcop->quota_disable(sb, qtype_enforce_flag(type));
104 return sb->s_qcop->quota_off(sb, type);
105}
106
107static int quota_getfmt(struct super_block *sb, int type, void __user *addr)
108{
109 __u32 fmt;
110
111 if (!sb_has_quota_active(sb, type))
112 return -ESRCH;
113 fmt = sb_dqopt(sb)->info[type].dqi_format->qf_fmt_id;
114 if (copy_to_user(addr, &fmt, sizeof(fmt)))
115 return -EFAULT;
116 return 0;
117}
118
119static int quota_getinfo(struct super_block *sb, int type, void __user *addr)
120{
121 struct qc_state state;
122 struct qc_type_state *tstate;
123 struct if_dqinfo uinfo;
124 int ret;
125
126 if (!sb->s_qcop->get_state)
127 return -ENOSYS;
128 ret = sb->s_qcop->get_state(sb, &state);
129 if (ret)
130 return ret;
131 tstate = state.s_state + type;
132 if (!(tstate->flags & QCI_ACCT_ENABLED))
133 return -ESRCH;
134 memset(&uinfo, 0, sizeof(uinfo));
135 uinfo.dqi_bgrace = tstate->spc_timelimit;
136 uinfo.dqi_igrace = tstate->ino_timelimit;
137 if (tstate->flags & QCI_SYSFILE)
138 uinfo.dqi_flags |= DQF_SYS_FILE;
139 if (tstate->flags & QCI_ROOT_SQUASH)
140 uinfo.dqi_flags |= DQF_ROOT_SQUASH;
141 uinfo.dqi_valid = IIF_ALL;
142 if (copy_to_user(addr, &uinfo, sizeof(uinfo)))
143 return -EFAULT;
144 return 0;
145}
146
147static int quota_setinfo(struct super_block *sb, int type, void __user *addr)
148{
149 struct if_dqinfo info;
150 struct qc_info qinfo;
151
152 if (copy_from_user(&info, addr, sizeof(info)))
153 return -EFAULT;
154 if (!sb->s_qcop->set_info)
155 return -ENOSYS;
156 if (info.dqi_valid & ~(IIF_FLAGS | IIF_BGRACE | IIF_IGRACE))
157 return -EINVAL;
158 memset(&qinfo, 0, sizeof(qinfo));
159 if (info.dqi_valid & IIF_FLAGS) {
160 if (info.dqi_flags & ~DQF_SETINFO_MASK)
161 return -EINVAL;
162 if (info.dqi_flags & DQF_ROOT_SQUASH)
163 qinfo.i_flags |= QCI_ROOT_SQUASH;
164 qinfo.i_fieldmask |= QC_FLAGS;
165 }
166 if (info.dqi_valid & IIF_BGRACE) {
167 qinfo.i_spc_timelimit = info.dqi_bgrace;
168 qinfo.i_fieldmask |= QC_SPC_TIMER;
169 }
170 if (info.dqi_valid & IIF_IGRACE) {
171 qinfo.i_ino_timelimit = info.dqi_igrace;
172 qinfo.i_fieldmask |= QC_INO_TIMER;
173 }
174 return sb->s_qcop->set_info(sb, type, &qinfo);
175}
176
177static inline qsize_t qbtos(qsize_t blocks)
178{
179 return blocks << QIF_DQBLKSIZE_BITS;
180}
181
182static inline qsize_t stoqb(qsize_t space)
183{
184 return (space + QIF_DQBLKSIZE - 1) >> QIF_DQBLKSIZE_BITS;
185}
186
187static void copy_to_if_dqblk(struct if_dqblk *dst, struct qc_dqblk *src)
188{
189 memset(dst, 0, sizeof(*dst));
190 dst->dqb_bhardlimit = stoqb(src->d_spc_hardlimit);
191 dst->dqb_bsoftlimit = stoqb(src->d_spc_softlimit);
192 dst->dqb_curspace = src->d_space;
193 dst->dqb_ihardlimit = src->d_ino_hardlimit;
194 dst->dqb_isoftlimit = src->d_ino_softlimit;
195 dst->dqb_curinodes = src->d_ino_count;
196 dst->dqb_btime = src->d_spc_timer;
197 dst->dqb_itime = src->d_ino_timer;
198 dst->dqb_valid = QIF_ALL;
199}
200
201static int quota_getquota(struct super_block *sb, int type, qid_t id,
202 void __user *addr)
203{
204 struct kqid qid;
205 struct qc_dqblk fdq;
206 struct if_dqblk idq;
207 int ret;
208
209 if (!sb->s_qcop->get_dqblk)
210 return -ENOSYS;
211 qid = make_kqid(current_user_ns(), type, id);
212 if (!qid_has_mapping(sb->s_user_ns, qid))
213 return -EINVAL;
214 ret = sb->s_qcop->get_dqblk(sb, qid, &fdq);
215 if (ret)
216 return ret;
217 copy_to_if_dqblk(&idq, &fdq);
218
219 if (compat_need_64bit_alignment_fixup()) {
220 struct compat_if_dqblk __user *compat_dqblk = addr;
221
222 if (copy_to_user(compat_dqblk, &idq, sizeof(*compat_dqblk)))
223 return -EFAULT;
224 if (put_user(idq.dqb_valid, &compat_dqblk->dqb_valid))
225 return -EFAULT;
226 } else {
227 if (copy_to_user(addr, &idq, sizeof(idq)))
228 return -EFAULT;
229 }
230 return 0;
231}
232
233/*
234 * Return quota for next active quota >= this id, if any exists,
235 * otherwise return -ENOENT via ->get_nextdqblk
236 */
237static int quota_getnextquota(struct super_block *sb, int type, qid_t id,
238 void __user *addr)
239{
240 struct kqid qid;
241 struct qc_dqblk fdq;
242 struct if_nextdqblk idq;
243 int ret;
244
245 if (!sb->s_qcop->get_nextdqblk)
246 return -ENOSYS;
247 qid = make_kqid(current_user_ns(), type, id);
248 if (!qid_has_mapping(sb->s_user_ns, qid))
249 return -EINVAL;
250 ret = sb->s_qcop->get_nextdqblk(sb, &qid, &fdq);
251 if (ret)
252 return ret;
253 /* struct if_nextdqblk is a superset of struct if_dqblk */
254 copy_to_if_dqblk((struct if_dqblk *)&idq, &fdq);
255 idq.dqb_id = from_kqid(current_user_ns(), qid);
256 if (copy_to_user(addr, &idq, sizeof(idq)))
257 return -EFAULT;
258 return 0;
259}
260
261static void copy_from_if_dqblk(struct qc_dqblk *dst, struct if_dqblk *src)
262{
263 dst->d_spc_hardlimit = qbtos(src->dqb_bhardlimit);
264 dst->d_spc_softlimit = qbtos(src->dqb_bsoftlimit);
265 dst->d_space = src->dqb_curspace;
266 dst->d_ino_hardlimit = src->dqb_ihardlimit;
267 dst->d_ino_softlimit = src->dqb_isoftlimit;
268 dst->d_ino_count = src->dqb_curinodes;
269 dst->d_spc_timer = src->dqb_btime;
270 dst->d_ino_timer = src->dqb_itime;
271
272 dst->d_fieldmask = 0;
273 if (src->dqb_valid & QIF_BLIMITS)
274 dst->d_fieldmask |= QC_SPC_SOFT | QC_SPC_HARD;
275 if (src->dqb_valid & QIF_SPACE)
276 dst->d_fieldmask |= QC_SPACE;
277 if (src->dqb_valid & QIF_ILIMITS)
278 dst->d_fieldmask |= QC_INO_SOFT | QC_INO_HARD;
279 if (src->dqb_valid & QIF_INODES)
280 dst->d_fieldmask |= QC_INO_COUNT;
281 if (src->dqb_valid & QIF_BTIME)
282 dst->d_fieldmask |= QC_SPC_TIMER;
283 if (src->dqb_valid & QIF_ITIME)
284 dst->d_fieldmask |= QC_INO_TIMER;
285}
286
287static int quota_setquota(struct super_block *sb, int type, qid_t id,
288 void __user *addr)
289{
290 struct qc_dqblk fdq;
291 struct if_dqblk idq;
292 struct kqid qid;
293
294 if (compat_need_64bit_alignment_fixup()) {
295 struct compat_if_dqblk __user *compat_dqblk = addr;
296
297 if (copy_from_user(&idq, compat_dqblk, sizeof(*compat_dqblk)) ||
298 get_user(idq.dqb_valid, &compat_dqblk->dqb_valid))
299 return -EFAULT;
300 } else {
301 if (copy_from_user(&idq, addr, sizeof(idq)))
302 return -EFAULT;
303 }
304 if (!sb->s_qcop->set_dqblk)
305 return -ENOSYS;
306 qid = make_kqid(current_user_ns(), type, id);
307 if (!qid_has_mapping(sb->s_user_ns, qid))
308 return -EINVAL;
309 copy_from_if_dqblk(&fdq, &idq);
310 return sb->s_qcop->set_dqblk(sb, qid, &fdq);
311}
312
313static int quota_enable(struct super_block *sb, void __user *addr)
314{
315 __u32 flags;
316
317 if (copy_from_user(&flags, addr, sizeof(flags)))
318 return -EFAULT;
319 if (!sb->s_qcop->quota_enable)
320 return -ENOSYS;
321 return sb->s_qcop->quota_enable(sb, flags);
322}
323
324static int quota_disable(struct super_block *sb, void __user *addr)
325{
326 __u32 flags;
327
328 if (copy_from_user(&flags, addr, sizeof(flags)))
329 return -EFAULT;
330 if (!sb->s_qcop->quota_disable)
331 return -ENOSYS;
332 return sb->s_qcop->quota_disable(sb, flags);
333}
334
335static int quota_state_to_flags(struct qc_state *state)
336{
337 int flags = 0;
338
339 if (state->s_state[USRQUOTA].flags & QCI_ACCT_ENABLED)
340 flags |= FS_QUOTA_UDQ_ACCT;
341 if (state->s_state[USRQUOTA].flags & QCI_LIMITS_ENFORCED)
342 flags |= FS_QUOTA_UDQ_ENFD;
343 if (state->s_state[GRPQUOTA].flags & QCI_ACCT_ENABLED)
344 flags |= FS_QUOTA_GDQ_ACCT;
345 if (state->s_state[GRPQUOTA].flags & QCI_LIMITS_ENFORCED)
346 flags |= FS_QUOTA_GDQ_ENFD;
347 if (state->s_state[PRJQUOTA].flags & QCI_ACCT_ENABLED)
348 flags |= FS_QUOTA_PDQ_ACCT;
349 if (state->s_state[PRJQUOTA].flags & QCI_LIMITS_ENFORCED)
350 flags |= FS_QUOTA_PDQ_ENFD;
351 return flags;
352}
353
354static int quota_getstate(struct super_block *sb, int type,
355 struct fs_quota_stat *fqs)
356{
357 struct qc_state state;
358 int ret;
359
360 memset(&state, 0, sizeof (struct qc_state));
361 ret = sb->s_qcop->get_state(sb, &state);
362 if (ret < 0)
363 return ret;
364
365 memset(fqs, 0, sizeof(*fqs));
366 fqs->qs_version = FS_QSTAT_VERSION;
367 fqs->qs_flags = quota_state_to_flags(&state);
368 /* No quota enabled? */
369 if (!fqs->qs_flags)
370 return -ENOSYS;
371 fqs->qs_incoredqs = state.s_incoredqs;
372
373 fqs->qs_btimelimit = state.s_state[type].spc_timelimit;
374 fqs->qs_itimelimit = state.s_state[type].ino_timelimit;
375 fqs->qs_rtbtimelimit = state.s_state[type].rt_spc_timelimit;
376 fqs->qs_bwarnlimit = state.s_state[type].spc_warnlimit;
377 fqs->qs_iwarnlimit = state.s_state[type].ino_warnlimit;
378
379 /* Inodes may be allocated even if inactive; copy out if present */
380 if (state.s_state[USRQUOTA].ino) {
381 fqs->qs_uquota.qfs_ino = state.s_state[USRQUOTA].ino;
382 fqs->qs_uquota.qfs_nblks = state.s_state[USRQUOTA].blocks;
383 fqs->qs_uquota.qfs_nextents = state.s_state[USRQUOTA].nextents;
384 }
385 if (state.s_state[GRPQUOTA].ino) {
386 fqs->qs_gquota.qfs_ino = state.s_state[GRPQUOTA].ino;
387 fqs->qs_gquota.qfs_nblks = state.s_state[GRPQUOTA].blocks;
388 fqs->qs_gquota.qfs_nextents = state.s_state[GRPQUOTA].nextents;
389 }
390 if (state.s_state[PRJQUOTA].ino) {
391 /*
392 * Q_XGETQSTAT doesn't have room for both group and project
393 * quotas. So, allow the project quota values to be copied out
394 * only if there is no group quota information available.
395 */
396 if (!(state.s_state[GRPQUOTA].flags & QCI_ACCT_ENABLED)) {
397 fqs->qs_gquota.qfs_ino = state.s_state[PRJQUOTA].ino;
398 fqs->qs_gquota.qfs_nblks =
399 state.s_state[PRJQUOTA].blocks;
400 fqs->qs_gquota.qfs_nextents =
401 state.s_state[PRJQUOTA].nextents;
402 }
403 }
404 return 0;
405}
406
407static int compat_copy_fs_qfilestat(struct compat_fs_qfilestat __user *to,
408 struct fs_qfilestat *from)
409{
410 if (copy_to_user(to, from, sizeof(*to)) ||
411 put_user(from->qfs_nextents, &to->qfs_nextents))
412 return -EFAULT;
413 return 0;
414}
415
416static int compat_copy_fs_quota_stat(struct compat_fs_quota_stat __user *to,
417 struct fs_quota_stat *from)
418{
419 if (put_user(from->qs_version, &to->qs_version) ||
420 put_user(from->qs_flags, &to->qs_flags) ||
421 put_user(from->qs_pad, &to->qs_pad) ||
422 compat_copy_fs_qfilestat(&to->qs_uquota, &from->qs_uquota) ||
423 compat_copy_fs_qfilestat(&to->qs_gquota, &from->qs_gquota) ||
424 put_user(from->qs_incoredqs, &to->qs_incoredqs) ||
425 put_user(from->qs_btimelimit, &to->qs_btimelimit) ||
426 put_user(from->qs_itimelimit, &to->qs_itimelimit) ||
427 put_user(from->qs_rtbtimelimit, &to->qs_rtbtimelimit) ||
428 put_user(from->qs_bwarnlimit, &to->qs_bwarnlimit) ||
429 put_user(from->qs_iwarnlimit, &to->qs_iwarnlimit))
430 return -EFAULT;
431 return 0;
432}
433
434static int quota_getxstate(struct super_block *sb, int type, void __user *addr)
435{
436 struct fs_quota_stat fqs;
437 int ret;
438
439 if (!sb->s_qcop->get_state)
440 return -ENOSYS;
441 ret = quota_getstate(sb, type, &fqs);
442 if (ret)
443 return ret;
444
445 if (compat_need_64bit_alignment_fixup())
446 return compat_copy_fs_quota_stat(addr, &fqs);
447 if (copy_to_user(addr, &fqs, sizeof(fqs)))
448 return -EFAULT;
449 return 0;
450}
451
452static int quota_getstatev(struct super_block *sb, int type,
453 struct fs_quota_statv *fqs)
454{
455 struct qc_state state;
456 int ret;
457
458 memset(&state, 0, sizeof (struct qc_state));
459 ret = sb->s_qcop->get_state(sb, &state);
460 if (ret < 0)
461 return ret;
462
463 memset(fqs, 0, sizeof(*fqs));
464 fqs->qs_version = FS_QSTAT_VERSION;
465 fqs->qs_flags = quota_state_to_flags(&state);
466 /* No quota enabled? */
467 if (!fqs->qs_flags)
468 return -ENOSYS;
469 fqs->qs_incoredqs = state.s_incoredqs;
470
471 fqs->qs_btimelimit = state.s_state[type].spc_timelimit;
472 fqs->qs_itimelimit = state.s_state[type].ino_timelimit;
473 fqs->qs_rtbtimelimit = state.s_state[type].rt_spc_timelimit;
474 fqs->qs_bwarnlimit = state.s_state[type].spc_warnlimit;
475 fqs->qs_iwarnlimit = state.s_state[type].ino_warnlimit;
476 fqs->qs_rtbwarnlimit = state.s_state[type].rt_spc_warnlimit;
477
478 /* Inodes may be allocated even if inactive; copy out if present */
479 if (state.s_state[USRQUOTA].ino) {
480 fqs->qs_uquota.qfs_ino = state.s_state[USRQUOTA].ino;
481 fqs->qs_uquota.qfs_nblks = state.s_state[USRQUOTA].blocks;
482 fqs->qs_uquota.qfs_nextents = state.s_state[USRQUOTA].nextents;
483 }
484 if (state.s_state[GRPQUOTA].ino) {
485 fqs->qs_gquota.qfs_ino = state.s_state[GRPQUOTA].ino;
486 fqs->qs_gquota.qfs_nblks = state.s_state[GRPQUOTA].blocks;
487 fqs->qs_gquota.qfs_nextents = state.s_state[GRPQUOTA].nextents;
488 }
489 if (state.s_state[PRJQUOTA].ino) {
490 fqs->qs_pquota.qfs_ino = state.s_state[PRJQUOTA].ino;
491 fqs->qs_pquota.qfs_nblks = state.s_state[PRJQUOTA].blocks;
492 fqs->qs_pquota.qfs_nextents = state.s_state[PRJQUOTA].nextents;
493 }
494 return 0;
495}
496
497static int quota_getxstatev(struct super_block *sb, int type, void __user *addr)
498{
499 struct fs_quota_statv fqs;
500 int ret;
501
502 if (!sb->s_qcop->get_state)
503 return -ENOSYS;
504
505 memset(&fqs, 0, sizeof(fqs));
506 if (copy_from_user(&fqs, addr, 1)) /* Just read qs_version */
507 return -EFAULT;
508
509 /* If this kernel doesn't support user specified version, fail */
510 switch (fqs.qs_version) {
511 case FS_QSTATV_VERSION1:
512 break;
513 default:
514 return -EINVAL;
515 }
516 ret = quota_getstatev(sb, type, &fqs);
517 if (!ret && copy_to_user(addr, &fqs, sizeof(fqs)))
518 return -EFAULT;
519 return ret;
520}
521
522/*
523 * XFS defines BBTOB and BTOBB macros inside fs/xfs/ and we cannot move them
524 * out of there as xfsprogs rely on definitions being in that header file. So
525 * just define same functions here for quota purposes.
526 */
527#define XFS_BB_SHIFT 9
528
529static inline u64 quota_bbtob(u64 blocks)
530{
531 return blocks << XFS_BB_SHIFT;
532}
533
534static inline u64 quota_btobb(u64 bytes)
535{
536 return (bytes + (1 << XFS_BB_SHIFT) - 1) >> XFS_BB_SHIFT;
537}
538
539static inline s64 copy_from_xfs_dqblk_ts(const struct fs_disk_quota *d,
540 __s32 timer, __s8 timer_hi)
541{
542 if (d->d_fieldmask & FS_DQ_BIGTIME)
543 return (u32)timer | (s64)timer_hi << 32;
544 return timer;
545}
546
547static void copy_from_xfs_dqblk(struct qc_dqblk *dst, struct fs_disk_quota *src)
548{
549 dst->d_spc_hardlimit = quota_bbtob(src->d_blk_hardlimit);
550 dst->d_spc_softlimit = quota_bbtob(src->d_blk_softlimit);
551 dst->d_ino_hardlimit = src->d_ino_hardlimit;
552 dst->d_ino_softlimit = src->d_ino_softlimit;
553 dst->d_space = quota_bbtob(src->d_bcount);
554 dst->d_ino_count = src->d_icount;
555 dst->d_ino_timer = copy_from_xfs_dqblk_ts(src, src->d_itimer,
556 src->d_itimer_hi);
557 dst->d_spc_timer = copy_from_xfs_dqblk_ts(src, src->d_btimer,
558 src->d_btimer_hi);
559 dst->d_ino_warns = src->d_iwarns;
560 dst->d_spc_warns = src->d_bwarns;
561 dst->d_rt_spc_hardlimit = quota_bbtob(src->d_rtb_hardlimit);
562 dst->d_rt_spc_softlimit = quota_bbtob(src->d_rtb_softlimit);
563 dst->d_rt_space = quota_bbtob(src->d_rtbcount);
564 dst->d_rt_spc_timer = copy_from_xfs_dqblk_ts(src, src->d_rtbtimer,
565 src->d_rtbtimer_hi);
566 dst->d_rt_spc_warns = src->d_rtbwarns;
567 dst->d_fieldmask = 0;
568 if (src->d_fieldmask & FS_DQ_ISOFT)
569 dst->d_fieldmask |= QC_INO_SOFT;
570 if (src->d_fieldmask & FS_DQ_IHARD)
571 dst->d_fieldmask |= QC_INO_HARD;
572 if (src->d_fieldmask & FS_DQ_BSOFT)
573 dst->d_fieldmask |= QC_SPC_SOFT;
574 if (src->d_fieldmask & FS_DQ_BHARD)
575 dst->d_fieldmask |= QC_SPC_HARD;
576 if (src->d_fieldmask & FS_DQ_RTBSOFT)
577 dst->d_fieldmask |= QC_RT_SPC_SOFT;
578 if (src->d_fieldmask & FS_DQ_RTBHARD)
579 dst->d_fieldmask |= QC_RT_SPC_HARD;
580 if (src->d_fieldmask & FS_DQ_BTIMER)
581 dst->d_fieldmask |= QC_SPC_TIMER;
582 if (src->d_fieldmask & FS_DQ_ITIMER)
583 dst->d_fieldmask |= QC_INO_TIMER;
584 if (src->d_fieldmask & FS_DQ_RTBTIMER)
585 dst->d_fieldmask |= QC_RT_SPC_TIMER;
586 if (src->d_fieldmask & FS_DQ_BWARNS)
587 dst->d_fieldmask |= QC_SPC_WARNS;
588 if (src->d_fieldmask & FS_DQ_IWARNS)
589 dst->d_fieldmask |= QC_INO_WARNS;
590 if (src->d_fieldmask & FS_DQ_RTBWARNS)
591 dst->d_fieldmask |= QC_RT_SPC_WARNS;
592 if (src->d_fieldmask & FS_DQ_BCOUNT)
593 dst->d_fieldmask |= QC_SPACE;
594 if (src->d_fieldmask & FS_DQ_ICOUNT)
595 dst->d_fieldmask |= QC_INO_COUNT;
596 if (src->d_fieldmask & FS_DQ_RTBCOUNT)
597 dst->d_fieldmask |= QC_RT_SPACE;
598}
599
600static void copy_qcinfo_from_xfs_dqblk(struct qc_info *dst,
601 struct fs_disk_quota *src)
602{
603 memset(dst, 0, sizeof(*dst));
604 dst->i_spc_timelimit = src->d_btimer;
605 dst->i_ino_timelimit = src->d_itimer;
606 dst->i_rt_spc_timelimit = src->d_rtbtimer;
607 dst->i_ino_warnlimit = src->d_iwarns;
608 dst->i_spc_warnlimit = src->d_bwarns;
609 dst->i_rt_spc_warnlimit = src->d_rtbwarns;
610 if (src->d_fieldmask & FS_DQ_BWARNS)
611 dst->i_fieldmask |= QC_SPC_WARNS;
612 if (src->d_fieldmask & FS_DQ_IWARNS)
613 dst->i_fieldmask |= QC_INO_WARNS;
614 if (src->d_fieldmask & FS_DQ_RTBWARNS)
615 dst->i_fieldmask |= QC_RT_SPC_WARNS;
616 if (src->d_fieldmask & FS_DQ_BTIMER)
617 dst->i_fieldmask |= QC_SPC_TIMER;
618 if (src->d_fieldmask & FS_DQ_ITIMER)
619 dst->i_fieldmask |= QC_INO_TIMER;
620 if (src->d_fieldmask & FS_DQ_RTBTIMER)
621 dst->i_fieldmask |= QC_RT_SPC_TIMER;
622}
623
624static int quota_setxquota(struct super_block *sb, int type, qid_t id,
625 void __user *addr)
626{
627 struct fs_disk_quota fdq;
628 struct qc_dqblk qdq;
629 struct kqid qid;
630
631 if (copy_from_user(&fdq, addr, sizeof(fdq)))
632 return -EFAULT;
633 if (!sb->s_qcop->set_dqblk)
634 return -ENOSYS;
635 qid = make_kqid(current_user_ns(), type, id);
636 if (!qid_has_mapping(sb->s_user_ns, qid))
637 return -EINVAL;
638 /* Are we actually setting timer / warning limits for all users? */
639 if (from_kqid(sb->s_user_ns, qid) == 0 &&
640 fdq.d_fieldmask & (FS_DQ_WARNS_MASK | FS_DQ_TIMER_MASK)) {
641 struct qc_info qinfo;
642 int ret;
643
644 if (!sb->s_qcop->set_info)
645 return -EINVAL;
646 copy_qcinfo_from_xfs_dqblk(&qinfo, &fdq);
647 ret = sb->s_qcop->set_info(sb, type, &qinfo);
648 if (ret)
649 return ret;
650 /* These are already done */
651 fdq.d_fieldmask &= ~(FS_DQ_WARNS_MASK | FS_DQ_TIMER_MASK);
652 }
653 copy_from_xfs_dqblk(&qdq, &fdq);
654 return sb->s_qcop->set_dqblk(sb, qid, &qdq);
655}
656
657static inline void copy_to_xfs_dqblk_ts(const struct fs_disk_quota *d,
658 __s32 *timer_lo, __s8 *timer_hi, s64 timer)
659{
660 *timer_lo = timer;
661 if (d->d_fieldmask & FS_DQ_BIGTIME)
662 *timer_hi = timer >> 32;
663}
664
665static inline bool want_bigtime(s64 timer)
666{
667 return timer > S32_MAX || timer < S32_MIN;
668}
669
670static void copy_to_xfs_dqblk(struct fs_disk_quota *dst, struct qc_dqblk *src,
671 int type, qid_t id)
672{
673 memset(dst, 0, sizeof(*dst));
674 if (want_bigtime(src->d_ino_timer) || want_bigtime(src->d_spc_timer) ||
675 want_bigtime(src->d_rt_spc_timer))
676 dst->d_fieldmask |= FS_DQ_BIGTIME;
677 dst->d_version = FS_DQUOT_VERSION;
678 dst->d_id = id;
679 if (type == USRQUOTA)
680 dst->d_flags = FS_USER_QUOTA;
681 else if (type == PRJQUOTA)
682 dst->d_flags = FS_PROJ_QUOTA;
683 else
684 dst->d_flags = FS_GROUP_QUOTA;
685 dst->d_blk_hardlimit = quota_btobb(src->d_spc_hardlimit);
686 dst->d_blk_softlimit = quota_btobb(src->d_spc_softlimit);
687 dst->d_ino_hardlimit = src->d_ino_hardlimit;
688 dst->d_ino_softlimit = src->d_ino_softlimit;
689 dst->d_bcount = quota_btobb(src->d_space);
690 dst->d_icount = src->d_ino_count;
691 copy_to_xfs_dqblk_ts(dst, &dst->d_itimer, &dst->d_itimer_hi,
692 src->d_ino_timer);
693 copy_to_xfs_dqblk_ts(dst, &dst->d_btimer, &dst->d_btimer_hi,
694 src->d_spc_timer);
695 dst->d_iwarns = src->d_ino_warns;
696 dst->d_bwarns = src->d_spc_warns;
697 dst->d_rtb_hardlimit = quota_btobb(src->d_rt_spc_hardlimit);
698 dst->d_rtb_softlimit = quota_btobb(src->d_rt_spc_softlimit);
699 dst->d_rtbcount = quota_btobb(src->d_rt_space);
700 copy_to_xfs_dqblk_ts(dst, &dst->d_rtbtimer, &dst->d_rtbtimer_hi,
701 src->d_rt_spc_timer);
702 dst->d_rtbwarns = src->d_rt_spc_warns;
703}
704
705static int quota_getxquota(struct super_block *sb, int type, qid_t id,
706 void __user *addr)
707{
708 struct fs_disk_quota fdq;
709 struct qc_dqblk qdq;
710 struct kqid qid;
711 int ret;
712
713 if (!sb->s_qcop->get_dqblk)
714 return -ENOSYS;
715 qid = make_kqid(current_user_ns(), type, id);
716 if (!qid_has_mapping(sb->s_user_ns, qid))
717 return -EINVAL;
718 ret = sb->s_qcop->get_dqblk(sb, qid, &qdq);
719 if (ret)
720 return ret;
721 copy_to_xfs_dqblk(&fdq, &qdq, type, id);
722 if (copy_to_user(addr, &fdq, sizeof(fdq)))
723 return -EFAULT;
724 return ret;
725}
726
727/*
728 * Return quota for next active quota >= this id, if any exists,
729 * otherwise return -ENOENT via ->get_nextdqblk.
730 */
731static int quota_getnextxquota(struct super_block *sb, int type, qid_t id,
732 void __user *addr)
733{
734 struct fs_disk_quota fdq;
735 struct qc_dqblk qdq;
736 struct kqid qid;
737 qid_t id_out;
738 int ret;
739
740 if (!sb->s_qcop->get_nextdqblk)
741 return -ENOSYS;
742 qid = make_kqid(current_user_ns(), type, id);
743 if (!qid_has_mapping(sb->s_user_ns, qid))
744 return -EINVAL;
745 ret = sb->s_qcop->get_nextdqblk(sb, &qid, &qdq);
746 if (ret)
747 return ret;
748 id_out = from_kqid(current_user_ns(), qid);
749 copy_to_xfs_dqblk(&fdq, &qdq, type, id_out);
750 if (copy_to_user(addr, &fdq, sizeof(fdq)))
751 return -EFAULT;
752 return ret;
753}
754
755static int quota_rmxquota(struct super_block *sb, void __user *addr)
756{
757 __u32 flags;
758
759 if (copy_from_user(&flags, addr, sizeof(flags)))
760 return -EFAULT;
761 if (!sb->s_qcop->rm_xquota)
762 return -ENOSYS;
763 return sb->s_qcop->rm_xquota(sb, flags);
764}
765
766/* Copy parameters and call proper function */
767static int do_quotactl(struct super_block *sb, int type, int cmd, qid_t id,
768 void __user *addr, const struct path *path)
769{
770 int ret;
771
772 type = array_index_nospec(type, MAXQUOTAS);
773 /*
774 * Quota not supported on this fs? Check this before s_quota_types
775 * since they needn't be set if quota is not supported at all.
776 */
777 if (!sb->s_qcop)
778 return -ENOSYS;
779 if (!(sb->s_quota_types & (1 << type)))
780 return -EINVAL;
781
782 ret = check_quotactl_permission(sb, type, cmd, id);
783 if (ret < 0)
784 return ret;
785
786 switch (cmd) {
787 case Q_QUOTAON:
788 return quota_quotaon(sb, type, id, path);
789 case Q_QUOTAOFF:
790 return quota_quotaoff(sb, type);
791 case Q_GETFMT:
792 return quota_getfmt(sb, type, addr);
793 case Q_GETINFO:
794 return quota_getinfo(sb, type, addr);
795 case Q_SETINFO:
796 return quota_setinfo(sb, type, addr);
797 case Q_GETQUOTA:
798 return quota_getquota(sb, type, id, addr);
799 case Q_GETNEXTQUOTA:
800 return quota_getnextquota(sb, type, id, addr);
801 case Q_SETQUOTA:
802 return quota_setquota(sb, type, id, addr);
803 case Q_SYNC:
804 if (!sb->s_qcop->quota_sync)
805 return -ENOSYS;
806 return sb->s_qcop->quota_sync(sb, type);
807 case Q_XQUOTAON:
808 return quota_enable(sb, addr);
809 case Q_XQUOTAOFF:
810 return quota_disable(sb, addr);
811 case Q_XQUOTARM:
812 return quota_rmxquota(sb, addr);
813 case Q_XGETQSTAT:
814 return quota_getxstate(sb, type, addr);
815 case Q_XGETQSTATV:
816 return quota_getxstatev(sb, type, addr);
817 case Q_XSETQLIM:
818 return quota_setxquota(sb, type, id, addr);
819 case Q_XGETQUOTA:
820 return quota_getxquota(sb, type, id, addr);
821 case Q_XGETNEXTQUOTA:
822 return quota_getnextxquota(sb, type, id, addr);
823 case Q_XQUOTASYNC:
824 if (sb_rdonly(sb))
825 return -EROFS;
826 /* XFS quotas are fully coherent now, making this call a noop */
827 return 0;
828 default:
829 return -EINVAL;
830 }
831}
832
833/* Return 1 if 'cmd' will block on frozen filesystem */
834static int quotactl_cmd_write(int cmd)
835{
836 /*
837 * We cannot allow Q_GETQUOTA and Q_GETNEXTQUOTA without write access
838 * as dquot_acquire() may allocate space for new structure and OCFS2
839 * needs to increment on-disk use count.
840 */
841 switch (cmd) {
842 case Q_GETFMT:
843 case Q_GETINFO:
844 case Q_SYNC:
845 case Q_XGETQSTAT:
846 case Q_XGETQSTATV:
847 case Q_XGETQUOTA:
848 case Q_XGETNEXTQUOTA:
849 case Q_XQUOTASYNC:
850 return 0;
851 }
852 return 1;
853}
854
855/* Return true if quotactl command is manipulating quota on/off state */
856static bool quotactl_cmd_onoff(int cmd)
857{
858 return (cmd == Q_QUOTAON) || (cmd == Q_QUOTAOFF) ||
859 (cmd == Q_XQUOTAON) || (cmd == Q_XQUOTAOFF);
860}
861
862/*
863 * look up a superblock on which quota ops will be performed
864 * - use the name of a block device to find the superblock thereon
865 */
866static struct super_block *quotactl_block(const char __user *special, int cmd)
867{
868#ifdef CONFIG_BLOCK
869 struct super_block *sb;
870 struct filename *tmp = getname(special);
871 bool excl = false, thawed = false;
872 int error;
873 dev_t dev;
874
875 if (IS_ERR(tmp))
876 return ERR_CAST(tmp);
877 error = lookup_bdev(tmp->name, &dev);
878 putname(tmp);
879 if (error)
880 return ERR_PTR(error);
881
882 if (quotactl_cmd_onoff(cmd)) {
883 excl = true;
884 thawed = true;
885 } else if (quotactl_cmd_write(cmd)) {
886 thawed = true;
887 }
888
889retry:
890 sb = user_get_super(dev, excl);
891 if (!sb)
892 return ERR_PTR(-ENODEV);
893 if (thawed && sb->s_writers.frozen != SB_UNFROZEN) {
894 if (excl)
895 up_write(&sb->s_umount);
896 else
897 up_read(&sb->s_umount);
898 wait_event(sb->s_writers.wait_unfrozen,
899 sb->s_writers.frozen == SB_UNFROZEN);
900 put_super(sb);
901 goto retry;
902 }
903 return sb;
904
905#else
906 return ERR_PTR(-ENODEV);
907#endif
908}
909
910/*
911 * This is the system call interface. This communicates with
912 * the user-level programs. Currently this only supports diskquota
913 * calls. Maybe we need to add the process quotas etc. in the future,
914 * but we probably should use rlimits for that.
915 */
916SYSCALL_DEFINE4(quotactl, unsigned int, cmd, const char __user *, special,
917 qid_t, id, void __user *, addr)
918{
919 uint cmds, type;
920 struct super_block *sb = NULL;
921 struct path path, *pathp = NULL;
922 int ret;
923
924 cmds = cmd >> SUBCMDSHIFT;
925 type = cmd & SUBCMDMASK;
926
927 if (type >= MAXQUOTAS)
928 return -EINVAL;
929
930 /*
931 * As a special case Q_SYNC can be called without a specific device.
932 * It will iterate all superblocks that have quota enabled and call
933 * the sync action on each of them.
934 */
935 if (!special) {
936 if (cmds == Q_SYNC)
937 return quota_sync_all(type);
938 return -ENODEV;
939 }
940
941 /*
942 * Path for quotaon has to be resolved before grabbing superblock
943 * because that gets s_umount sem which is also possibly needed by path
944 * resolution (think about autofs) and thus deadlocks could arise.
945 */
946 if (cmds == Q_QUOTAON) {
947 ret = user_path_at(AT_FDCWD, addr, LOOKUP_FOLLOW|LOOKUP_AUTOMOUNT, &path);
948 if (ret)
949 pathp = ERR_PTR(ret);
950 else
951 pathp = &path;
952 }
953
954 sb = quotactl_block(special, cmds);
955 if (IS_ERR(sb)) {
956 ret = PTR_ERR(sb);
957 goto out;
958 }
959
960 ret = do_quotactl(sb, type, cmds, id, addr, pathp);
961
962 if (!quotactl_cmd_onoff(cmds))
963 drop_super(sb);
964 else
965 drop_super_exclusive(sb);
966out:
967 if (pathp && !IS_ERR(pathp))
968 path_put(pathp);
969 return ret;
970}
971
972SYSCALL_DEFINE4(quotactl_fd, unsigned int, fd, unsigned int, cmd,
973 qid_t, id, void __user *, addr)
974{
975 struct super_block *sb;
976 unsigned int cmds = cmd >> SUBCMDSHIFT;
977 unsigned int type = cmd & SUBCMDMASK;
978 struct fd f;
979 int ret;
980
981 f = fdget_raw(fd);
982 if (!f.file)
983 return -EBADF;
984
985 ret = -EINVAL;
986 if (type >= MAXQUOTAS)
987 goto out;
988
989 if (quotactl_cmd_write(cmds)) {
990 ret = mnt_want_write(f.file->f_path.mnt);
991 if (ret)
992 goto out;
993 }
994
995 sb = f.file->f_path.mnt->mnt_sb;
996 if (quotactl_cmd_onoff(cmds))
997 down_write(&sb->s_umount);
998 else
999 down_read(&sb->s_umount);
1000
1001 ret = do_quotactl(sb, type, cmds, id, addr, ERR_PTR(-EINVAL));
1002
1003 if (quotactl_cmd_onoff(cmds))
1004 up_write(&sb->s_umount);
1005 else
1006 up_read(&sb->s_umount);
1007
1008 if (quotactl_cmd_write(cmds))
1009 mnt_drop_write(f.file->f_path.mnt);
1010out:
1011 fdput(f);
1012 return ret;
1013}