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
check_quotactl_permission(struct super_block * sb,int type,int cmd,qid_t id)27 static 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
quota_sync_one(struct super_block * sb,void * arg)54 static 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
quota_sync_all(int type)63 static 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
qtype_enforce_flag(int type)73 unsigned 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
quota_quotaon(struct super_block * sb,int type,qid_t id,const struct path * path)86 static 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
quota_quotaoff(struct super_block * sb,int type)98 static 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
quota_getfmt(struct super_block * sb,int type,void __user * addr)107 static 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
quota_getinfo(struct super_block * sb,int type,void __user * addr)119 static 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
quota_setinfo(struct super_block * sb,int type,void __user * addr)147 static 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
qbtos(qsize_t blocks)177 static inline qsize_t qbtos(qsize_t blocks)
178 {
179 return blocks << QIF_DQBLKSIZE_BITS;
180 }
181
stoqb(qsize_t space)182 static inline qsize_t stoqb(qsize_t space)
183 {
184 return (space + QIF_DQBLKSIZE - 1) >> QIF_DQBLKSIZE_BITS;
185 }
186
copy_to_if_dqblk(struct if_dqblk * dst,struct qc_dqblk * src)187 static 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
quota_getquota(struct super_block * sb,int type,qid_t id,void __user * addr)201 static 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 */
quota_getnextquota(struct super_block * sb,int type,qid_t id,void __user * addr)237 static 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
copy_from_if_dqblk(struct qc_dqblk * dst,struct if_dqblk * src)261 static 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
quota_setquota(struct super_block * sb,int type,qid_t id,void __user * addr)287 static 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
quota_enable(struct super_block * sb,void __user * addr)313 static 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
quota_disable(struct super_block * sb,void __user * addr)324 static 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
quota_state_to_flags(struct qc_state * state)335 static 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
quota_getstate(struct super_block * sb,int type,struct fs_quota_stat * fqs)354 static 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
compat_copy_fs_qfilestat(struct compat_fs_qfilestat __user * to,struct fs_qfilestat * from)407 static 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
compat_copy_fs_quota_stat(struct compat_fs_quota_stat __user * to,struct fs_quota_stat * from)416 static 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
quota_getxstate(struct super_block * sb,int type,void __user * addr)434 static 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
quota_getstatev(struct super_block * sb,int type,struct fs_quota_statv * fqs)452 static 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
quota_getxstatev(struct super_block * sb,int type,void __user * addr)497 static 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
quota_bbtob(u64 blocks)529 static inline u64 quota_bbtob(u64 blocks)
530 {
531 return blocks << XFS_BB_SHIFT;
532 }
533
quota_btobb(u64 bytes)534 static inline u64 quota_btobb(u64 bytes)
535 {
536 return (bytes + (1 << XFS_BB_SHIFT) - 1) >> XFS_BB_SHIFT;
537 }
538
copy_from_xfs_dqblk_ts(const struct fs_disk_quota * d,__s32 timer,__s8 timer_hi)539 static 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
copy_from_xfs_dqblk(struct qc_dqblk * dst,struct fs_disk_quota * src)547 static 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
copy_qcinfo_from_xfs_dqblk(struct qc_info * dst,struct fs_disk_quota * src)600 static 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
quota_setxquota(struct super_block * sb,int type,qid_t id,void __user * addr)624 static 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
copy_to_xfs_dqblk_ts(const struct fs_disk_quota * d,__s32 * timer_lo,__s8 * timer_hi,s64 timer)657 static 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
want_bigtime(s64 timer)665 static inline bool want_bigtime(s64 timer)
666 {
667 return timer > S32_MAX || timer < S32_MIN;
668 }
669
copy_to_xfs_dqblk(struct fs_disk_quota * dst,struct qc_dqblk * src,int type,qid_t id)670 static 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
quota_getxquota(struct super_block * sb,int type,qid_t id,void __user * addr)705 static 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 */
quota_getnextxquota(struct super_block * sb,int type,qid_t id,void __user * addr)731 static 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
quota_rmxquota(struct super_block * sb,void __user * addr)755 static 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 */
do_quotactl(struct super_block * sb,int type,int cmd,qid_t id,void __user * addr,const struct path * path)767 static 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 */
quotactl_cmd_write(int cmd)834 static 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 */
quotactl_cmd_onoff(int cmd)856 static 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 */
quotactl_block(const char __user * special,int cmd)866 static 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
889 retry:
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 for sb to unfreeze */
899 sb_start_write(sb);
900 sb_end_write(sb);
901 put_super(sb);
902 goto retry;
903 }
904 return sb;
905
906 #else
907 return ERR_PTR(-ENODEV);
908 #endif
909 }
910
911 /*
912 * This is the system call interface. This communicates with
913 * the user-level programs. Currently this only supports diskquota
914 * calls. Maybe we need to add the process quotas etc. in the future,
915 * but we probably should use rlimits for that.
916 */
SYSCALL_DEFINE4(quotactl,unsigned int,cmd,const char __user *,special,qid_t,id,void __user *,addr)917 SYSCALL_DEFINE4(quotactl, unsigned int, cmd, const char __user *, special,
918 qid_t, id, void __user *, addr)
919 {
920 uint cmds, type;
921 struct super_block *sb = NULL;
922 struct path path, *pathp = NULL;
923 int ret;
924
925 cmds = cmd >> SUBCMDSHIFT;
926 type = cmd & SUBCMDMASK;
927
928 if (type >= MAXQUOTAS)
929 return -EINVAL;
930
931 /*
932 * As a special case Q_SYNC can be called without a specific device.
933 * It will iterate all superblocks that have quota enabled and call
934 * the sync action on each of them.
935 */
936 if (!special) {
937 if (cmds == Q_SYNC)
938 return quota_sync_all(type);
939 return -ENODEV;
940 }
941
942 /*
943 * Path for quotaon has to be resolved before grabbing superblock
944 * because that gets s_umount sem which is also possibly needed by path
945 * resolution (think about autofs) and thus deadlocks could arise.
946 */
947 if (cmds == Q_QUOTAON) {
948 ret = user_path_at(AT_FDCWD, addr, LOOKUP_FOLLOW|LOOKUP_AUTOMOUNT, &path);
949 if (ret)
950 pathp = ERR_PTR(ret);
951 else
952 pathp = &path;
953 }
954
955 sb = quotactl_block(special, cmds);
956 if (IS_ERR(sb)) {
957 ret = PTR_ERR(sb);
958 goto out;
959 }
960
961 ret = do_quotactl(sb, type, cmds, id, addr, pathp);
962
963 if (!quotactl_cmd_onoff(cmds))
964 drop_super(sb);
965 else
966 drop_super_exclusive(sb);
967 out:
968 if (pathp && !IS_ERR(pathp))
969 path_put(pathp);
970 return ret;
971 }
972
SYSCALL_DEFINE4(quotactl_fd,unsigned int,fd,unsigned int,cmd,qid_t,id,void __user *,addr)973 SYSCALL_DEFINE4(quotactl_fd, unsigned int, fd, unsigned int, cmd,
974 qid_t, id, void __user *, addr)
975 {
976 struct super_block *sb;
977 unsigned int cmds = cmd >> SUBCMDSHIFT;
978 unsigned int type = cmd & SUBCMDMASK;
979 struct fd f;
980 int ret;
981
982 f = fdget_raw(fd);
983 if (!fd_file(f))
984 return -EBADF;
985
986 ret = -EINVAL;
987 if (type >= MAXQUOTAS)
988 goto out;
989
990 if (quotactl_cmd_write(cmds)) {
991 ret = mnt_want_write(fd_file(f)->f_path.mnt);
992 if (ret)
993 goto out;
994 }
995
996 sb = fd_file(f)->f_path.mnt->mnt_sb;
997 if (quotactl_cmd_onoff(cmds))
998 down_write(&sb->s_umount);
999 else
1000 down_read(&sb->s_umount);
1001
1002 ret = do_quotactl(sb, type, cmds, id, addr, ERR_PTR(-EINVAL));
1003
1004 if (quotactl_cmd_onoff(cmds))
1005 up_write(&sb->s_umount);
1006 else
1007 up_read(&sb->s_umount);
1008
1009 if (quotactl_cmd_write(cmds))
1010 mnt_drop_write(fd_file(f)->f_path.mnt);
1011 out:
1012 fdput(f);
1013 return ret;
1014 }
1015