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/uaccess.h>
14 #include <linux/kernel.h>
15 #include <linux/security.h>
16 #include <linux/syscalls.h>
17 #include <linux/capability.h>
18 #include <linux/quotaops.h>
19 #include <linux/types.h>
20 #include <linux/writeback.h>
21 #include <linux/nospec.h>
22
check_quotactl_permission(struct super_block * sb,int type,int cmd,qid_t id)23 static int check_quotactl_permission(struct super_block *sb, int type, int cmd,
24 qid_t id)
25 {
26 switch (cmd) {
27 /* these commands do not require any special privilegues */
28 case Q_GETFMT:
29 case Q_SYNC:
30 case Q_GETINFO:
31 case Q_XGETQSTAT:
32 case Q_XGETQSTATV:
33 case Q_XQUOTASYNC:
34 break;
35 /* allow to query information for dquots we "own" */
36 case Q_GETQUOTA:
37 case Q_XGETQUOTA:
38 if ((type == USRQUOTA && uid_eq(current_euid(), make_kuid(current_user_ns(), id))) ||
39 (type == GRPQUOTA && in_egroup_p(make_kgid(current_user_ns(), id))))
40 break;
41 /*FALLTHROUGH*/
42 default:
43 if (!capable(CAP_SYS_ADMIN))
44 return -EPERM;
45 }
46
47 return security_quotactl(cmd, type, id, sb);
48 }
49
quota_sync_one(struct super_block * sb,void * arg)50 static void quota_sync_one(struct super_block *sb, void *arg)
51 {
52 int type = *(int *)arg;
53
54 if (sb->s_qcop && sb->s_qcop->quota_sync &&
55 (sb->s_quota_types & (1 << type)))
56 sb->s_qcop->quota_sync(sb, type);
57 }
58
quota_sync_all(int type)59 static int quota_sync_all(int type)
60 {
61 int ret;
62
63 if (type >= MAXQUOTAS)
64 return -EINVAL;
65 ret = security_quotactl(Q_SYNC, type, 0, NULL);
66 if (!ret)
67 iterate_supers(quota_sync_one, &type);
68 return ret;
69 }
70
qtype_enforce_flag(int type)71 unsigned int qtype_enforce_flag(int type)
72 {
73 switch (type) {
74 case USRQUOTA:
75 return FS_QUOTA_UDQ_ENFD;
76 case GRPQUOTA:
77 return FS_QUOTA_GDQ_ENFD;
78 case PRJQUOTA:
79 return FS_QUOTA_PDQ_ENFD;
80 }
81 return 0;
82 }
83
quota_quotaon(struct super_block * sb,int type,qid_t id,const struct path * path)84 static int quota_quotaon(struct super_block *sb, int type, qid_t id,
85 const struct path *path)
86 {
87 if (!sb->s_qcop->quota_on && !sb->s_qcop->quota_enable)
88 return -ENOSYS;
89 if (sb->s_qcop->quota_enable)
90 return sb->s_qcop->quota_enable(sb, qtype_enforce_flag(type));
91 if (IS_ERR(path))
92 return PTR_ERR(path);
93 return sb->s_qcop->quota_on(sb, type, id, path);
94 }
95
quota_quotaoff(struct super_block * sb,int type)96 static int quota_quotaoff(struct super_block *sb, int type)
97 {
98 if (!sb->s_qcop->quota_off && !sb->s_qcop->quota_disable)
99 return -ENOSYS;
100 if (sb->s_qcop->quota_disable)
101 return sb->s_qcop->quota_disable(sb, qtype_enforce_flag(type));
102 return sb->s_qcop->quota_off(sb, type);
103 }
104
quota_getfmt(struct super_block * sb,int type,void __user * addr)105 static int quota_getfmt(struct super_block *sb, int type, void __user *addr)
106 {
107 __u32 fmt;
108
109 if (!sb_has_quota_active(sb, type))
110 return -ESRCH;
111 fmt = sb_dqopt(sb)->info[type].dqi_format->qf_fmt_id;
112 if (copy_to_user(addr, &fmt, sizeof(fmt)))
113 return -EFAULT;
114 return 0;
115 }
116
quota_getinfo(struct super_block * sb,int type,void __user * addr)117 static int quota_getinfo(struct super_block *sb, int type, void __user *addr)
118 {
119 struct qc_state state;
120 struct qc_type_state *tstate;
121 struct if_dqinfo uinfo;
122 int ret;
123
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
quota_setinfo(struct super_block * sb,int type,void __user * addr)145 static 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
qbtos(qsize_t blocks)175 static inline qsize_t qbtos(qsize_t blocks)
176 {
177 return blocks << QIF_DQBLKSIZE_BITS;
178 }
179
stoqb(qsize_t space)180 static inline qsize_t stoqb(qsize_t space)
181 {
182 return (space + QIF_DQBLKSIZE - 1) >> QIF_DQBLKSIZE_BITS;
183 }
184
copy_to_if_dqblk(struct if_dqblk * dst,struct qc_dqblk * src)185 static 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
quota_getquota(struct super_block * sb,int type,qid_t id,void __user * addr)199 static 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 */
quota_getnextquota(struct super_block * sb,int type,qid_t id,void __user * addr)225 static 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
copy_from_if_dqblk(struct qc_dqblk * dst,struct if_dqblk * src)249 static 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
quota_setquota(struct super_block * sb,int type,qid_t id,void __user * addr)275 static 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
quota_enable(struct super_block * sb,void __user * addr)293 static 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
quota_disable(struct super_block * sb,void __user * addr)304 static 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
quota_state_to_flags(struct qc_state * state)315 static 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
quota_getstate(struct super_block * sb,struct fs_quota_stat * fqs)334 static 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 < MAXQUOTAS; type++)
357 if (state.s_state[type].flags & QCI_ACCT_ENABLED)
358 break;
359 BUG_ON(type == 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
quota_getxstate(struct super_block * sb,void __user * addr)394 static 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
quota_getstatev(struct super_block * sb,struct fs_quota_statv * fqs)407 static 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 < MAXQUOTAS; type++)
430 if (state.s_state[type].flags & QCI_ACCT_ENABLED)
431 break;
432 BUG_ON(type == 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
quota_getxstatev(struct super_block * sb,void __user * addr)458 static 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
quota_bbtob(u64 blocks)490 static inline u64 quota_bbtob(u64 blocks)
491 {
492 return blocks << XFS_BB_SHIFT;
493 }
494
quota_btobb(u64 bytes)495 static inline u64 quota_btobb(u64 bytes)
496 {
497 return (bytes + (1 << XFS_BB_SHIFT) - 1) >> XFS_BB_SHIFT;
498 }
499
copy_from_xfs_dqblk(struct qc_dqblk * dst,struct fs_disk_quota * src)500 static 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
copy_qcinfo_from_xfs_dqblk(struct qc_info * dst,struct fs_disk_quota * src)550 static 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
quota_setxquota(struct super_block * sb,int type,qid_t id,void __user * addr)574 static 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
copy_to_xfs_dqblk(struct fs_disk_quota * dst,struct qc_dqblk * src,int type,qid_t id)607 static 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
quota_getxquota(struct super_block * sb,int type,qid_t id,void __user * addr)636 static 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 */
quota_getnextxquota(struct super_block * sb,int type,qid_t id,void __user * addr)662 static 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
quota_rmxquota(struct super_block * sb,void __user * addr)686 static 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 */
do_quotactl(struct super_block * sb,int type,int cmd,qid_t id,void __user * addr,const struct path * path)698 static 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 >= MAXQUOTAS)
704 return -EINVAL;
705 type = array_index_nospec(type, MAXQUOTAS);
706 /*
707 * Quota not supported on this fs? Check this before s_quota_types
708 * since they needn't be set if quota is not supported at all.
709 */
710 if (!sb->s_qcop)
711 return -ENOSYS;
712 if (!(sb->s_quota_types & (1 << type)))
713 return -EINVAL;
714
715 ret = check_quotactl_permission(sb, type, cmd, id);
716 if (ret < 0)
717 return ret;
718
719 switch (cmd) {
720 case Q_QUOTAON:
721 return quota_quotaon(sb, type, id, path);
722 case Q_QUOTAOFF:
723 return quota_quotaoff(sb, type);
724 case Q_GETFMT:
725 return quota_getfmt(sb, type, addr);
726 case Q_GETINFO:
727 return quota_getinfo(sb, type, addr);
728 case Q_SETINFO:
729 return quota_setinfo(sb, type, addr);
730 case Q_GETQUOTA:
731 return quota_getquota(sb, type, id, addr);
732 case Q_GETNEXTQUOTA:
733 return quota_getnextquota(sb, type, id, addr);
734 case Q_SETQUOTA:
735 return quota_setquota(sb, type, id, addr);
736 case Q_SYNC:
737 if (!sb->s_qcop->quota_sync)
738 return -ENOSYS;
739 return sb->s_qcop->quota_sync(sb, type);
740 case Q_XQUOTAON:
741 return quota_enable(sb, addr);
742 case Q_XQUOTAOFF:
743 return quota_disable(sb, addr);
744 case Q_XQUOTARM:
745 return quota_rmxquota(sb, addr);
746 case Q_XGETQSTAT:
747 return quota_getxstate(sb, addr);
748 case Q_XGETQSTATV:
749 return quota_getxstatev(sb, addr);
750 case Q_XSETQLIM:
751 return quota_setxquota(sb, type, id, addr);
752 case Q_XGETQUOTA:
753 return quota_getxquota(sb, type, id, addr);
754 case Q_XGETNEXTQUOTA:
755 return quota_getnextxquota(sb, type, id, addr);
756 case Q_XQUOTASYNC:
757 if (sb_rdonly(sb))
758 return -EROFS;
759 /* XFS quotas are fully coherent now, making this call a noop */
760 return 0;
761 default:
762 return -EINVAL;
763 }
764 }
765
766 #ifdef CONFIG_BLOCK
767
768 /* Return 1 if 'cmd' will block on frozen filesystem */
quotactl_cmd_write(int cmd)769 static int quotactl_cmd_write(int cmd)
770 {
771 /*
772 * We cannot allow Q_GETQUOTA and Q_GETNEXTQUOTA without write access
773 * as dquot_acquire() may allocate space for new structure and OCFS2
774 * needs to increment on-disk use count.
775 */
776 switch (cmd) {
777 case Q_GETFMT:
778 case Q_GETINFO:
779 case Q_SYNC:
780 case Q_XGETQSTAT:
781 case Q_XGETQSTATV:
782 case Q_XGETQUOTA:
783 case Q_XGETNEXTQUOTA:
784 case Q_XQUOTASYNC:
785 return 0;
786 }
787 return 1;
788 }
789 #endif /* CONFIG_BLOCK */
790
791 /* Return true if quotactl command is manipulating quota on/off state */
quotactl_cmd_onoff(int cmd)792 static bool quotactl_cmd_onoff(int cmd)
793 {
794 return (cmd == Q_QUOTAON) || (cmd == Q_QUOTAOFF) ||
795 (cmd == Q_XQUOTAON) || (cmd == Q_XQUOTAOFF);
796 }
797
798 /*
799 * look up a superblock on which quota ops will be performed
800 * - use the name of a block device to find the superblock thereon
801 */
quotactl_block(const char __user * special,int cmd)802 static struct super_block *quotactl_block(const char __user *special, int cmd)
803 {
804 #ifdef CONFIG_BLOCK
805 struct block_device *bdev;
806 struct super_block *sb;
807 struct filename *tmp = getname(special);
808
809 if (IS_ERR(tmp))
810 return ERR_CAST(tmp);
811 bdev = lookup_bdev(tmp->name);
812 putname(tmp);
813 if (IS_ERR(bdev))
814 return ERR_CAST(bdev);
815 if (quotactl_cmd_onoff(cmd))
816 sb = get_super_exclusive_thawed(bdev);
817 else if (quotactl_cmd_write(cmd))
818 sb = get_super_thawed(bdev);
819 else
820 sb = get_super(bdev);
821 bdput(bdev);
822 if (!sb)
823 return ERR_PTR(-ENODEV);
824
825 return sb;
826 #else
827 return ERR_PTR(-ENODEV);
828 #endif
829 }
830
831 /*
832 * This is the system call interface. This communicates with
833 * the user-level programs. Currently this only supports diskquota
834 * calls. Maybe we need to add the process quotas etc. in the future,
835 * but we probably should use rlimits for that.
836 */
kernel_quotactl(unsigned int cmd,const char __user * special,qid_t id,void __user * addr)837 int kernel_quotactl(unsigned int cmd, const char __user *special,
838 qid_t id, void __user *addr)
839 {
840 uint cmds, type;
841 struct super_block *sb = NULL;
842 struct path path, *pathp = NULL;
843 int ret;
844
845 cmds = cmd >> SUBCMDSHIFT;
846 type = cmd & SUBCMDMASK;
847
848 /*
849 * As a special case Q_SYNC can be called without a specific device.
850 * It will iterate all superblocks that have quota enabled and call
851 * the sync action on each of them.
852 */
853 if (!special) {
854 if (cmds == Q_SYNC)
855 return quota_sync_all(type);
856 return -ENODEV;
857 }
858
859 /*
860 * Path for quotaon has to be resolved before grabbing superblock
861 * because that gets s_umount sem which is also possibly needed by path
862 * resolution (think about autofs) and thus deadlocks could arise.
863 */
864 if (cmds == Q_QUOTAON) {
865 ret = user_path_at(AT_FDCWD, addr, LOOKUP_FOLLOW|LOOKUP_AUTOMOUNT, &path);
866 if (ret)
867 pathp = ERR_PTR(ret);
868 else
869 pathp = &path;
870 }
871
872 sb = quotactl_block(special, cmds);
873 if (IS_ERR(sb)) {
874 ret = PTR_ERR(sb);
875 goto out;
876 }
877
878 ret = do_quotactl(sb, type, cmds, id, addr, pathp);
879
880 if (!quotactl_cmd_onoff(cmds))
881 drop_super(sb);
882 else
883 drop_super_exclusive(sb);
884 out:
885 if (pathp && !IS_ERR(pathp))
886 path_put(pathp);
887 return ret;
888 }
889
SYSCALL_DEFINE4(quotactl,unsigned int,cmd,const char __user *,special,qid_t,id,void __user *,addr)890 SYSCALL_DEFINE4(quotactl, unsigned int, cmd, const char __user *, special,
891 qid_t, id, void __user *, addr)
892 {
893 return kernel_quotactl(cmd, special, id, addr);
894 }
895