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0001 // SPDX-License-Identifier: GPL-2.0
0002 /*
0003  * Quota code necessary even when VFS quota support is not compiled
0004  * into the kernel.  The interesting stuff is over in dquot.c, here
0005  * we have symbols for initial quotactl(2) handling, the sysctl(2)
0006  * variables, etc - things needed even when quota support disabled.
0007  */
0008 
0009 #include <linux/fs.h>
0010 #include <linux/namei.h>
0011 #include <linux/slab.h>
0012 #include <asm/current.h>
0013 #include <linux/blkdev.h>
0014 #include <linux/uaccess.h>
0015 #include <linux/kernel.h>
0016 #include <linux/security.h>
0017 #include <linux/syscalls.h>
0018 #include <linux/capability.h>
0019 #include <linux/quotaops.h>
0020 #include <linux/types.h>
0021 #include <linux/mount.h>
0022 #include <linux/writeback.h>
0023 #include <linux/nospec.h>
0024 #include "compat.h"
0025 #include "../internal.h"
0026 
0027 static int check_quotactl_permission(struct super_block *sb, int type, int cmd,
0028                      qid_t id)
0029 {
0030     switch (cmd) {
0031     /* these commands do not require any special privilegues */
0032     case Q_GETFMT:
0033     case Q_SYNC:
0034     case Q_GETINFO:
0035     case Q_XGETQSTAT:
0036     case Q_XGETQSTATV:
0037     case Q_XQUOTASYNC:
0038         break;
0039     /* allow to query information for dquots we "own" */
0040     case Q_GETQUOTA:
0041     case Q_XGETQUOTA:
0042         if ((type == USRQUOTA && uid_eq(current_euid(), make_kuid(current_user_ns(), id))) ||
0043             (type == GRPQUOTA && in_egroup_p(make_kgid(current_user_ns(), id))))
0044             break;
0045         fallthrough;
0046     default:
0047         if (!capable(CAP_SYS_ADMIN))
0048             return -EPERM;
0049     }
0050 
0051     return security_quotactl(cmd, type, id, sb);
0052 }
0053 
0054 static void quota_sync_one(struct super_block *sb, void *arg)
0055 {
0056     int type = *(int *)arg;
0057 
0058     if (sb->s_qcop && sb->s_qcop->quota_sync &&
0059         (sb->s_quota_types & (1 << type)))
0060         sb->s_qcop->quota_sync(sb, type);
0061 }
0062 
0063 static int quota_sync_all(int type)
0064 {
0065     int ret;
0066 
0067     ret = security_quotactl(Q_SYNC, type, 0, NULL);
0068     if (!ret)
0069         iterate_supers(quota_sync_one, &type);
0070     return ret;
0071 }
0072 
0073 unsigned int qtype_enforce_flag(int type)
0074 {
0075     switch (type) {
0076     case USRQUOTA:
0077         return FS_QUOTA_UDQ_ENFD;
0078     case GRPQUOTA:
0079         return FS_QUOTA_GDQ_ENFD;
0080     case PRJQUOTA:
0081         return FS_QUOTA_PDQ_ENFD;
0082     }
0083     return 0;
0084 }
0085 
0086 static int quota_quotaon(struct super_block *sb, int type, qid_t id,
0087                  const struct path *path)
0088 {
0089     if (!sb->s_qcop->quota_on && !sb->s_qcop->quota_enable)
0090         return -ENOSYS;
0091     if (sb->s_qcop->quota_enable)
0092         return sb->s_qcop->quota_enable(sb, qtype_enforce_flag(type));
0093     if (IS_ERR(path))
0094         return PTR_ERR(path);
0095     return sb->s_qcop->quota_on(sb, type, id, path);
0096 }
0097 
0098 static int quota_quotaoff(struct super_block *sb, int type)
0099 {
0100     if (!sb->s_qcop->quota_off && !sb->s_qcop->quota_disable)
0101         return -ENOSYS;
0102     if (sb->s_qcop->quota_disable)
0103         return sb->s_qcop->quota_disable(sb, qtype_enforce_flag(type));
0104     return sb->s_qcop->quota_off(sb, type);
0105 }
0106 
0107 static int quota_getfmt(struct super_block *sb, int type, void __user *addr)
0108 {
0109     __u32 fmt;
0110 
0111     if (!sb_has_quota_active(sb, type))
0112         return -ESRCH;
0113     fmt = sb_dqopt(sb)->info[type].dqi_format->qf_fmt_id;
0114     if (copy_to_user(addr, &fmt, sizeof(fmt)))
0115         return -EFAULT;
0116     return 0;
0117 }
0118 
0119 static int quota_getinfo(struct super_block *sb, int type, void __user *addr)
0120 {
0121     struct qc_state state;
0122     struct qc_type_state *tstate;
0123     struct if_dqinfo uinfo;
0124     int ret;
0125 
0126     if (!sb->s_qcop->get_state)
0127         return -ENOSYS;
0128     ret = sb->s_qcop->get_state(sb, &state);
0129     if (ret)
0130         return ret;
0131     tstate = state.s_state + type;
0132     if (!(tstate->flags & QCI_ACCT_ENABLED))
0133         return -ESRCH;
0134     memset(&uinfo, 0, sizeof(uinfo));
0135     uinfo.dqi_bgrace = tstate->spc_timelimit;
0136     uinfo.dqi_igrace = tstate->ino_timelimit;
0137     if (tstate->flags & QCI_SYSFILE)
0138         uinfo.dqi_flags |= DQF_SYS_FILE;
0139     if (tstate->flags & QCI_ROOT_SQUASH)
0140         uinfo.dqi_flags |= DQF_ROOT_SQUASH;
0141     uinfo.dqi_valid = IIF_ALL;
0142     if (copy_to_user(addr, &uinfo, sizeof(uinfo)))
0143         return -EFAULT;
0144     return 0;
0145 }
0146 
0147 static int quota_setinfo(struct super_block *sb, int type, void __user *addr)
0148 {
0149     struct if_dqinfo info;
0150     struct qc_info qinfo;
0151 
0152     if (copy_from_user(&info, addr, sizeof(info)))
0153         return -EFAULT;
0154     if (!sb->s_qcop->set_info)
0155         return -ENOSYS;
0156     if (info.dqi_valid & ~(IIF_FLAGS | IIF_BGRACE | IIF_IGRACE))
0157         return -EINVAL;
0158     memset(&qinfo, 0, sizeof(qinfo));
0159     if (info.dqi_valid & IIF_FLAGS) {
0160         if (info.dqi_flags & ~DQF_SETINFO_MASK)
0161             return -EINVAL;
0162         if (info.dqi_flags & DQF_ROOT_SQUASH)
0163             qinfo.i_flags |= QCI_ROOT_SQUASH;
0164         qinfo.i_fieldmask |= QC_FLAGS;
0165     }
0166     if (info.dqi_valid & IIF_BGRACE) {
0167         qinfo.i_spc_timelimit = info.dqi_bgrace;
0168         qinfo.i_fieldmask |= QC_SPC_TIMER;
0169     }
0170     if (info.dqi_valid & IIF_IGRACE) {
0171         qinfo.i_ino_timelimit = info.dqi_igrace;
0172         qinfo.i_fieldmask |= QC_INO_TIMER;
0173     }
0174     return sb->s_qcop->set_info(sb, type, &qinfo);
0175 }
0176 
0177 static inline qsize_t qbtos(qsize_t blocks)
0178 {
0179     return blocks << QIF_DQBLKSIZE_BITS;
0180 }
0181 
0182 static inline qsize_t stoqb(qsize_t space)
0183 {
0184     return (space + QIF_DQBLKSIZE - 1) >> QIF_DQBLKSIZE_BITS;
0185 }
0186 
0187 static void copy_to_if_dqblk(struct if_dqblk *dst, struct qc_dqblk *src)
0188 {
0189     memset(dst, 0, sizeof(*dst));
0190     dst->dqb_bhardlimit = stoqb(src->d_spc_hardlimit);
0191     dst->dqb_bsoftlimit = stoqb(src->d_spc_softlimit);
0192     dst->dqb_curspace = src->d_space;
0193     dst->dqb_ihardlimit = src->d_ino_hardlimit;
0194     dst->dqb_isoftlimit = src->d_ino_softlimit;
0195     dst->dqb_curinodes = src->d_ino_count;
0196     dst->dqb_btime = src->d_spc_timer;
0197     dst->dqb_itime = src->d_ino_timer;
0198     dst->dqb_valid = QIF_ALL;
0199 }
0200 
0201 static int quota_getquota(struct super_block *sb, int type, qid_t id,
0202               void __user *addr)
0203 {
0204     struct kqid qid;
0205     struct qc_dqblk fdq;
0206     struct if_dqblk idq;
0207     int ret;
0208 
0209     if (!sb->s_qcop->get_dqblk)
0210         return -ENOSYS;
0211     qid = make_kqid(current_user_ns(), type, id);
0212     if (!qid_has_mapping(sb->s_user_ns, qid))
0213         return -EINVAL;
0214     ret = sb->s_qcop->get_dqblk(sb, qid, &fdq);
0215     if (ret)
0216         return ret;
0217     copy_to_if_dqblk(&idq, &fdq);
0218 
0219     if (compat_need_64bit_alignment_fixup()) {
0220         struct compat_if_dqblk __user *compat_dqblk = addr;
0221 
0222         if (copy_to_user(compat_dqblk, &idq, sizeof(*compat_dqblk)))
0223             return -EFAULT;
0224         if (put_user(idq.dqb_valid, &compat_dqblk->dqb_valid))
0225             return -EFAULT;
0226     } else {
0227         if (copy_to_user(addr, &idq, sizeof(idq)))
0228             return -EFAULT;
0229     }
0230     return 0;
0231 }
0232 
0233 /*
0234  * Return quota for next active quota >= this id, if any exists,
0235  * otherwise return -ENOENT via ->get_nextdqblk
0236  */
0237 static int quota_getnextquota(struct super_block *sb, int type, qid_t id,
0238               void __user *addr)
0239 {
0240     struct kqid qid;
0241     struct qc_dqblk fdq;
0242     struct if_nextdqblk idq;
0243     int ret;
0244 
0245     if (!sb->s_qcop->get_nextdqblk)
0246         return -ENOSYS;
0247     qid = make_kqid(current_user_ns(), type, id);
0248     if (!qid_has_mapping(sb->s_user_ns, qid))
0249         return -EINVAL;
0250     ret = sb->s_qcop->get_nextdqblk(sb, &qid, &fdq);
0251     if (ret)
0252         return ret;
0253     /* struct if_nextdqblk is a superset of struct if_dqblk */
0254     copy_to_if_dqblk((struct if_dqblk *)&idq, &fdq);
0255     idq.dqb_id = from_kqid(current_user_ns(), qid);
0256     if (copy_to_user(addr, &idq, sizeof(idq)))
0257         return -EFAULT;
0258     return 0;
0259 }
0260 
0261 static void copy_from_if_dqblk(struct qc_dqblk *dst, struct if_dqblk *src)
0262 {
0263     dst->d_spc_hardlimit = qbtos(src->dqb_bhardlimit);
0264     dst->d_spc_softlimit = qbtos(src->dqb_bsoftlimit);
0265     dst->d_space = src->dqb_curspace;
0266     dst->d_ino_hardlimit = src->dqb_ihardlimit;
0267     dst->d_ino_softlimit = src->dqb_isoftlimit;
0268     dst->d_ino_count = src->dqb_curinodes;
0269     dst->d_spc_timer = src->dqb_btime;
0270     dst->d_ino_timer = src->dqb_itime;
0271 
0272     dst->d_fieldmask = 0;
0273     if (src->dqb_valid & QIF_BLIMITS)
0274         dst->d_fieldmask |= QC_SPC_SOFT | QC_SPC_HARD;
0275     if (src->dqb_valid & QIF_SPACE)
0276         dst->d_fieldmask |= QC_SPACE;
0277     if (src->dqb_valid & QIF_ILIMITS)
0278         dst->d_fieldmask |= QC_INO_SOFT | QC_INO_HARD;
0279     if (src->dqb_valid & QIF_INODES)
0280         dst->d_fieldmask |= QC_INO_COUNT;
0281     if (src->dqb_valid & QIF_BTIME)
0282         dst->d_fieldmask |= QC_SPC_TIMER;
0283     if (src->dqb_valid & QIF_ITIME)
0284         dst->d_fieldmask |= QC_INO_TIMER;
0285 }
0286 
0287 static int quota_setquota(struct super_block *sb, int type, qid_t id,
0288               void __user *addr)
0289 {
0290     struct qc_dqblk fdq;
0291     struct if_dqblk idq;
0292     struct kqid qid;
0293 
0294     if (compat_need_64bit_alignment_fixup()) {
0295         struct compat_if_dqblk __user *compat_dqblk = addr;
0296 
0297         if (copy_from_user(&idq, compat_dqblk, sizeof(*compat_dqblk)) ||
0298             get_user(idq.dqb_valid, &compat_dqblk->dqb_valid))
0299             return -EFAULT;
0300     } else {
0301         if (copy_from_user(&idq, addr, sizeof(idq)))
0302             return -EFAULT;
0303     }
0304     if (!sb->s_qcop->set_dqblk)
0305         return -ENOSYS;
0306     qid = make_kqid(current_user_ns(), type, id);
0307     if (!qid_has_mapping(sb->s_user_ns, qid))
0308         return -EINVAL;
0309     copy_from_if_dqblk(&fdq, &idq);
0310     return sb->s_qcop->set_dqblk(sb, qid, &fdq);
0311 }
0312 
0313 static int quota_enable(struct super_block *sb, void __user *addr)
0314 {
0315     __u32 flags;
0316 
0317     if (copy_from_user(&flags, addr, sizeof(flags)))
0318         return -EFAULT;
0319     if (!sb->s_qcop->quota_enable)
0320         return -ENOSYS;
0321     return sb->s_qcop->quota_enable(sb, flags);
0322 }
0323 
0324 static int quota_disable(struct super_block *sb, void __user *addr)
0325 {
0326     __u32 flags;
0327 
0328     if (copy_from_user(&flags, addr, sizeof(flags)))
0329         return -EFAULT;
0330     if (!sb->s_qcop->quota_disable)
0331         return -ENOSYS;
0332     return sb->s_qcop->quota_disable(sb, flags);
0333 }
0334 
0335 static int quota_state_to_flags(struct qc_state *state)
0336 {
0337     int flags = 0;
0338 
0339     if (state->s_state[USRQUOTA].flags & QCI_ACCT_ENABLED)
0340         flags |= FS_QUOTA_UDQ_ACCT;
0341     if (state->s_state[USRQUOTA].flags & QCI_LIMITS_ENFORCED)
0342         flags |= FS_QUOTA_UDQ_ENFD;
0343     if (state->s_state[GRPQUOTA].flags & QCI_ACCT_ENABLED)
0344         flags |= FS_QUOTA_GDQ_ACCT;
0345     if (state->s_state[GRPQUOTA].flags & QCI_LIMITS_ENFORCED)
0346         flags |= FS_QUOTA_GDQ_ENFD;
0347     if (state->s_state[PRJQUOTA].flags & QCI_ACCT_ENABLED)
0348         flags |= FS_QUOTA_PDQ_ACCT;
0349     if (state->s_state[PRJQUOTA].flags & QCI_LIMITS_ENFORCED)
0350         flags |= FS_QUOTA_PDQ_ENFD;
0351     return flags;
0352 }
0353 
0354 static int quota_getstate(struct super_block *sb, int type,
0355               struct fs_quota_stat *fqs)
0356 {
0357     struct qc_state state;
0358     int ret;
0359 
0360     memset(&state, 0, sizeof (struct qc_state));
0361     ret = sb->s_qcop->get_state(sb, &state);
0362     if (ret < 0)
0363         return ret;
0364 
0365     memset(fqs, 0, sizeof(*fqs));
0366     fqs->qs_version = FS_QSTAT_VERSION;
0367     fqs->qs_flags = quota_state_to_flags(&state);
0368     /* No quota enabled? */
0369     if (!fqs->qs_flags)
0370         return -ENOSYS;
0371     fqs->qs_incoredqs = state.s_incoredqs;
0372 
0373     fqs->qs_btimelimit = state.s_state[type].spc_timelimit;
0374     fqs->qs_itimelimit = state.s_state[type].ino_timelimit;
0375     fqs->qs_rtbtimelimit = state.s_state[type].rt_spc_timelimit;
0376     fqs->qs_bwarnlimit = state.s_state[type].spc_warnlimit;
0377     fqs->qs_iwarnlimit = state.s_state[type].ino_warnlimit;
0378 
0379     /* Inodes may be allocated even if inactive; copy out if present */
0380     if (state.s_state[USRQUOTA].ino) {
0381         fqs->qs_uquota.qfs_ino = state.s_state[USRQUOTA].ino;
0382         fqs->qs_uquota.qfs_nblks = state.s_state[USRQUOTA].blocks;
0383         fqs->qs_uquota.qfs_nextents = state.s_state[USRQUOTA].nextents;
0384     }
0385     if (state.s_state[GRPQUOTA].ino) {
0386         fqs->qs_gquota.qfs_ino = state.s_state[GRPQUOTA].ino;
0387         fqs->qs_gquota.qfs_nblks = state.s_state[GRPQUOTA].blocks;
0388         fqs->qs_gquota.qfs_nextents = state.s_state[GRPQUOTA].nextents;
0389     }
0390     if (state.s_state[PRJQUOTA].ino) {
0391         /*
0392          * Q_XGETQSTAT doesn't have room for both group and project
0393          * quotas.  So, allow the project quota values to be copied out
0394          * only if there is no group quota information available.
0395          */
0396         if (!(state.s_state[GRPQUOTA].flags & QCI_ACCT_ENABLED)) {
0397             fqs->qs_gquota.qfs_ino = state.s_state[PRJQUOTA].ino;
0398             fqs->qs_gquota.qfs_nblks =
0399                     state.s_state[PRJQUOTA].blocks;
0400             fqs->qs_gquota.qfs_nextents =
0401                     state.s_state[PRJQUOTA].nextents;
0402         }
0403     }
0404     return 0;
0405 }
0406 
0407 static int compat_copy_fs_qfilestat(struct compat_fs_qfilestat __user *to,
0408         struct fs_qfilestat *from)
0409 {
0410     if (copy_to_user(to, from, sizeof(*to)) ||
0411         put_user(from->qfs_nextents, &to->qfs_nextents))
0412         return -EFAULT;
0413     return 0;
0414 }
0415 
0416 static int compat_copy_fs_quota_stat(struct compat_fs_quota_stat __user *to,
0417         struct fs_quota_stat *from)
0418 {
0419     if (put_user(from->qs_version, &to->qs_version) ||
0420         put_user(from->qs_flags, &to->qs_flags) ||
0421         put_user(from->qs_pad, &to->qs_pad) ||
0422         compat_copy_fs_qfilestat(&to->qs_uquota, &from->qs_uquota) ||
0423         compat_copy_fs_qfilestat(&to->qs_gquota, &from->qs_gquota) ||
0424         put_user(from->qs_incoredqs, &to->qs_incoredqs) ||
0425         put_user(from->qs_btimelimit, &to->qs_btimelimit) ||
0426         put_user(from->qs_itimelimit, &to->qs_itimelimit) ||
0427         put_user(from->qs_rtbtimelimit, &to->qs_rtbtimelimit) ||
0428         put_user(from->qs_bwarnlimit, &to->qs_bwarnlimit) ||
0429         put_user(from->qs_iwarnlimit, &to->qs_iwarnlimit))
0430         return -EFAULT;
0431     return 0;
0432 }
0433 
0434 static int quota_getxstate(struct super_block *sb, int type, void __user *addr)
0435 {
0436     struct fs_quota_stat fqs;
0437     int ret;
0438 
0439     if (!sb->s_qcop->get_state)
0440         return -ENOSYS;
0441     ret = quota_getstate(sb, type, &fqs);
0442     if (ret)
0443         return ret;
0444 
0445     if (compat_need_64bit_alignment_fixup())
0446         return compat_copy_fs_quota_stat(addr, &fqs);
0447     if (copy_to_user(addr, &fqs, sizeof(fqs)))
0448         return -EFAULT;
0449     return 0;
0450 }
0451 
0452 static int quota_getstatev(struct super_block *sb, int type,
0453                struct fs_quota_statv *fqs)
0454 {
0455     struct qc_state state;
0456     int ret;
0457 
0458     memset(&state, 0, sizeof (struct qc_state));
0459     ret = sb->s_qcop->get_state(sb, &state);
0460     if (ret < 0)
0461         return ret;
0462 
0463     memset(fqs, 0, sizeof(*fqs));
0464     fqs->qs_version = FS_QSTAT_VERSION;
0465     fqs->qs_flags = quota_state_to_flags(&state);
0466     /* No quota enabled? */
0467     if (!fqs->qs_flags)
0468         return -ENOSYS;
0469     fqs->qs_incoredqs = state.s_incoredqs;
0470 
0471     fqs->qs_btimelimit = state.s_state[type].spc_timelimit;
0472     fqs->qs_itimelimit = state.s_state[type].ino_timelimit;
0473     fqs->qs_rtbtimelimit = state.s_state[type].rt_spc_timelimit;
0474     fqs->qs_bwarnlimit = state.s_state[type].spc_warnlimit;
0475     fqs->qs_iwarnlimit = state.s_state[type].ino_warnlimit;
0476     fqs->qs_rtbwarnlimit = state.s_state[type].rt_spc_warnlimit;
0477 
0478     /* Inodes may be allocated even if inactive; copy out if present */
0479     if (state.s_state[USRQUOTA].ino) {
0480         fqs->qs_uquota.qfs_ino = state.s_state[USRQUOTA].ino;
0481         fqs->qs_uquota.qfs_nblks = state.s_state[USRQUOTA].blocks;
0482         fqs->qs_uquota.qfs_nextents = state.s_state[USRQUOTA].nextents;
0483     }
0484     if (state.s_state[GRPQUOTA].ino) {
0485         fqs->qs_gquota.qfs_ino = state.s_state[GRPQUOTA].ino;
0486         fqs->qs_gquota.qfs_nblks = state.s_state[GRPQUOTA].blocks;
0487         fqs->qs_gquota.qfs_nextents = state.s_state[GRPQUOTA].nextents;
0488     }
0489     if (state.s_state[PRJQUOTA].ino) {
0490         fqs->qs_pquota.qfs_ino = state.s_state[PRJQUOTA].ino;
0491         fqs->qs_pquota.qfs_nblks = state.s_state[PRJQUOTA].blocks;
0492         fqs->qs_pquota.qfs_nextents = state.s_state[PRJQUOTA].nextents;
0493     }
0494     return 0;
0495 }
0496 
0497 static int quota_getxstatev(struct super_block *sb, int type, void __user *addr)
0498 {
0499     struct fs_quota_statv fqs;
0500     int ret;
0501 
0502     if (!sb->s_qcop->get_state)
0503         return -ENOSYS;
0504 
0505     memset(&fqs, 0, sizeof(fqs));
0506     if (copy_from_user(&fqs, addr, 1)) /* Just read qs_version */
0507         return -EFAULT;
0508 
0509     /* If this kernel doesn't support user specified version, fail */
0510     switch (fqs.qs_version) {
0511     case FS_QSTATV_VERSION1:
0512         break;
0513     default:
0514         return -EINVAL;
0515     }
0516     ret = quota_getstatev(sb, type, &fqs);
0517     if (!ret && copy_to_user(addr, &fqs, sizeof(fqs)))
0518         return -EFAULT;
0519     return ret;
0520 }
0521 
0522 /*
0523  * XFS defines BBTOB and BTOBB macros inside fs/xfs/ and we cannot move them
0524  * out of there as xfsprogs rely on definitions being in that header file. So
0525  * just define same functions here for quota purposes.
0526  */
0527 #define XFS_BB_SHIFT 9
0528 
0529 static inline u64 quota_bbtob(u64 blocks)
0530 {
0531     return blocks << XFS_BB_SHIFT;
0532 }
0533 
0534 static inline u64 quota_btobb(u64 bytes)
0535 {
0536     return (bytes + (1 << XFS_BB_SHIFT) - 1) >> XFS_BB_SHIFT;
0537 }
0538 
0539 static inline s64 copy_from_xfs_dqblk_ts(const struct fs_disk_quota *d,
0540         __s32 timer, __s8 timer_hi)
0541 {
0542     if (d->d_fieldmask & FS_DQ_BIGTIME)
0543         return (u32)timer | (s64)timer_hi << 32;
0544     return timer;
0545 }
0546 
0547 static void copy_from_xfs_dqblk(struct qc_dqblk *dst, struct fs_disk_quota *src)
0548 {
0549     dst->d_spc_hardlimit = quota_bbtob(src->d_blk_hardlimit);
0550     dst->d_spc_softlimit = quota_bbtob(src->d_blk_softlimit);
0551     dst->d_ino_hardlimit = src->d_ino_hardlimit;
0552     dst->d_ino_softlimit = src->d_ino_softlimit;
0553     dst->d_space = quota_bbtob(src->d_bcount);
0554     dst->d_ino_count = src->d_icount;
0555     dst->d_ino_timer = copy_from_xfs_dqblk_ts(src, src->d_itimer,
0556                           src->d_itimer_hi);
0557     dst->d_spc_timer = copy_from_xfs_dqblk_ts(src, src->d_btimer,
0558                           src->d_btimer_hi);
0559     dst->d_ino_warns = src->d_iwarns;
0560     dst->d_spc_warns = src->d_bwarns;
0561     dst->d_rt_spc_hardlimit = quota_bbtob(src->d_rtb_hardlimit);
0562     dst->d_rt_spc_softlimit = quota_bbtob(src->d_rtb_softlimit);
0563     dst->d_rt_space = quota_bbtob(src->d_rtbcount);
0564     dst->d_rt_spc_timer = copy_from_xfs_dqblk_ts(src, src->d_rtbtimer,
0565                              src->d_rtbtimer_hi);
0566     dst->d_rt_spc_warns = src->d_rtbwarns;
0567     dst->d_fieldmask = 0;
0568     if (src->d_fieldmask & FS_DQ_ISOFT)
0569         dst->d_fieldmask |= QC_INO_SOFT;
0570     if (src->d_fieldmask & FS_DQ_IHARD)
0571         dst->d_fieldmask |= QC_INO_HARD;
0572     if (src->d_fieldmask & FS_DQ_BSOFT)
0573         dst->d_fieldmask |= QC_SPC_SOFT;
0574     if (src->d_fieldmask & FS_DQ_BHARD)
0575         dst->d_fieldmask |= QC_SPC_HARD;
0576     if (src->d_fieldmask & FS_DQ_RTBSOFT)
0577         dst->d_fieldmask |= QC_RT_SPC_SOFT;
0578     if (src->d_fieldmask & FS_DQ_RTBHARD)
0579         dst->d_fieldmask |= QC_RT_SPC_HARD;
0580     if (src->d_fieldmask & FS_DQ_BTIMER)
0581         dst->d_fieldmask |= QC_SPC_TIMER;
0582     if (src->d_fieldmask & FS_DQ_ITIMER)
0583         dst->d_fieldmask |= QC_INO_TIMER;
0584     if (src->d_fieldmask & FS_DQ_RTBTIMER)
0585         dst->d_fieldmask |= QC_RT_SPC_TIMER;
0586     if (src->d_fieldmask & FS_DQ_BWARNS)
0587         dst->d_fieldmask |= QC_SPC_WARNS;
0588     if (src->d_fieldmask & FS_DQ_IWARNS)
0589         dst->d_fieldmask |= QC_INO_WARNS;
0590     if (src->d_fieldmask & FS_DQ_RTBWARNS)
0591         dst->d_fieldmask |= QC_RT_SPC_WARNS;
0592     if (src->d_fieldmask & FS_DQ_BCOUNT)
0593         dst->d_fieldmask |= QC_SPACE;
0594     if (src->d_fieldmask & FS_DQ_ICOUNT)
0595         dst->d_fieldmask |= QC_INO_COUNT;
0596     if (src->d_fieldmask & FS_DQ_RTBCOUNT)
0597         dst->d_fieldmask |= QC_RT_SPACE;
0598 }
0599 
0600 static void copy_qcinfo_from_xfs_dqblk(struct qc_info *dst,
0601                        struct fs_disk_quota *src)
0602 {
0603     memset(dst, 0, sizeof(*dst));
0604     dst->i_spc_timelimit = src->d_btimer;
0605     dst->i_ino_timelimit = src->d_itimer;
0606     dst->i_rt_spc_timelimit = src->d_rtbtimer;
0607     dst->i_ino_warnlimit = src->d_iwarns;
0608     dst->i_spc_warnlimit = src->d_bwarns;
0609     dst->i_rt_spc_warnlimit = src->d_rtbwarns;
0610     if (src->d_fieldmask & FS_DQ_BWARNS)
0611         dst->i_fieldmask |= QC_SPC_WARNS;
0612     if (src->d_fieldmask & FS_DQ_IWARNS)
0613         dst->i_fieldmask |= QC_INO_WARNS;
0614     if (src->d_fieldmask & FS_DQ_RTBWARNS)
0615         dst->i_fieldmask |= QC_RT_SPC_WARNS;
0616     if (src->d_fieldmask & FS_DQ_BTIMER)
0617         dst->i_fieldmask |= QC_SPC_TIMER;
0618     if (src->d_fieldmask & FS_DQ_ITIMER)
0619         dst->i_fieldmask |= QC_INO_TIMER;
0620     if (src->d_fieldmask & FS_DQ_RTBTIMER)
0621         dst->i_fieldmask |= QC_RT_SPC_TIMER;
0622 }
0623 
0624 static int quota_setxquota(struct super_block *sb, int type, qid_t id,
0625                void __user *addr)
0626 {
0627     struct fs_disk_quota fdq;
0628     struct qc_dqblk qdq;
0629     struct kqid qid;
0630 
0631     if (copy_from_user(&fdq, addr, sizeof(fdq)))
0632         return -EFAULT;
0633     if (!sb->s_qcop->set_dqblk)
0634         return -ENOSYS;
0635     qid = make_kqid(current_user_ns(), type, id);
0636     if (!qid_has_mapping(sb->s_user_ns, qid))
0637         return -EINVAL;
0638     /* Are we actually setting timer / warning limits for all users? */
0639     if (from_kqid(sb->s_user_ns, qid) == 0 &&
0640         fdq.d_fieldmask & (FS_DQ_WARNS_MASK | FS_DQ_TIMER_MASK)) {
0641         struct qc_info qinfo;
0642         int ret;
0643 
0644         if (!sb->s_qcop->set_info)
0645             return -EINVAL;
0646         copy_qcinfo_from_xfs_dqblk(&qinfo, &fdq);
0647         ret = sb->s_qcop->set_info(sb, type, &qinfo);
0648         if (ret)
0649             return ret;
0650         /* These are already done */
0651         fdq.d_fieldmask &= ~(FS_DQ_WARNS_MASK | FS_DQ_TIMER_MASK);
0652     }
0653     copy_from_xfs_dqblk(&qdq, &fdq);
0654     return sb->s_qcop->set_dqblk(sb, qid, &qdq);
0655 }
0656 
0657 static inline void copy_to_xfs_dqblk_ts(const struct fs_disk_quota *d,
0658         __s32 *timer_lo, __s8 *timer_hi, s64 timer)
0659 {
0660     *timer_lo = timer;
0661     if (d->d_fieldmask & FS_DQ_BIGTIME)
0662         *timer_hi = timer >> 32;
0663 }
0664 
0665 static inline bool want_bigtime(s64 timer)
0666 {
0667     return timer > S32_MAX || timer < S32_MIN;
0668 }
0669 
0670 static void copy_to_xfs_dqblk(struct fs_disk_quota *dst, struct qc_dqblk *src,
0671                   int type, qid_t id)
0672 {
0673     memset(dst, 0, sizeof(*dst));
0674     if (want_bigtime(src->d_ino_timer) || want_bigtime(src->d_spc_timer) ||
0675         want_bigtime(src->d_rt_spc_timer))
0676         dst->d_fieldmask |= FS_DQ_BIGTIME;
0677     dst->d_version = FS_DQUOT_VERSION;
0678     dst->d_id = id;
0679     if (type == USRQUOTA)
0680         dst->d_flags = FS_USER_QUOTA;
0681     else if (type == PRJQUOTA)
0682         dst->d_flags = FS_PROJ_QUOTA;
0683     else
0684         dst->d_flags = FS_GROUP_QUOTA;
0685     dst->d_blk_hardlimit = quota_btobb(src->d_spc_hardlimit);
0686     dst->d_blk_softlimit = quota_btobb(src->d_spc_softlimit);
0687     dst->d_ino_hardlimit = src->d_ino_hardlimit;
0688     dst->d_ino_softlimit = src->d_ino_softlimit;
0689     dst->d_bcount = quota_btobb(src->d_space);
0690     dst->d_icount = src->d_ino_count;
0691     copy_to_xfs_dqblk_ts(dst, &dst->d_itimer, &dst->d_itimer_hi,
0692                  src->d_ino_timer);
0693     copy_to_xfs_dqblk_ts(dst, &dst->d_btimer, &dst->d_btimer_hi,
0694                  src->d_spc_timer);
0695     dst->d_iwarns = src->d_ino_warns;
0696     dst->d_bwarns = src->d_spc_warns;
0697     dst->d_rtb_hardlimit = quota_btobb(src->d_rt_spc_hardlimit);
0698     dst->d_rtb_softlimit = quota_btobb(src->d_rt_spc_softlimit);
0699     dst->d_rtbcount = quota_btobb(src->d_rt_space);
0700     copy_to_xfs_dqblk_ts(dst, &dst->d_rtbtimer, &dst->d_rtbtimer_hi,
0701                  src->d_rt_spc_timer);
0702     dst->d_rtbwarns = src->d_rt_spc_warns;
0703 }
0704 
0705 static int quota_getxquota(struct super_block *sb, int type, qid_t id,
0706                void __user *addr)
0707 {
0708     struct fs_disk_quota fdq;
0709     struct qc_dqblk qdq;
0710     struct kqid qid;
0711     int ret;
0712 
0713     if (!sb->s_qcop->get_dqblk)
0714         return -ENOSYS;
0715     qid = make_kqid(current_user_ns(), type, id);
0716     if (!qid_has_mapping(sb->s_user_ns, qid))
0717         return -EINVAL;
0718     ret = sb->s_qcop->get_dqblk(sb, qid, &qdq);
0719     if (ret)
0720         return ret;
0721     copy_to_xfs_dqblk(&fdq, &qdq, type, id);
0722     if (copy_to_user(addr, &fdq, sizeof(fdq)))
0723         return -EFAULT;
0724     return ret;
0725 }
0726 
0727 /*
0728  * Return quota for next active quota >= this id, if any exists,
0729  * otherwise return -ENOENT via ->get_nextdqblk.
0730  */
0731 static int quota_getnextxquota(struct super_block *sb, int type, qid_t id,
0732                 void __user *addr)
0733 {
0734     struct fs_disk_quota fdq;
0735     struct qc_dqblk qdq;
0736     struct kqid qid;
0737     qid_t id_out;
0738     int ret;
0739 
0740     if (!sb->s_qcop->get_nextdqblk)
0741         return -ENOSYS;
0742     qid = make_kqid(current_user_ns(), type, id);
0743     if (!qid_has_mapping(sb->s_user_ns, qid))
0744         return -EINVAL;
0745     ret = sb->s_qcop->get_nextdqblk(sb, &qid, &qdq);
0746     if (ret)
0747         return ret;
0748     id_out = from_kqid(current_user_ns(), qid);
0749     copy_to_xfs_dqblk(&fdq, &qdq, type, id_out);
0750     if (copy_to_user(addr, &fdq, sizeof(fdq)))
0751         return -EFAULT;
0752     return ret;
0753 }
0754 
0755 static int quota_rmxquota(struct super_block *sb, void __user *addr)
0756 {
0757     __u32 flags;
0758 
0759     if (copy_from_user(&flags, addr, sizeof(flags)))
0760         return -EFAULT;
0761     if (!sb->s_qcop->rm_xquota)
0762         return -ENOSYS;
0763     return sb->s_qcop->rm_xquota(sb, flags);
0764 }
0765 
0766 /* Copy parameters and call proper function */
0767 static int do_quotactl(struct super_block *sb, int type, int cmd, qid_t id,
0768                void __user *addr, const struct path *path)
0769 {
0770     int ret;
0771 
0772     type = array_index_nospec(type, MAXQUOTAS);
0773     /*
0774      * Quota not supported on this fs? Check this before s_quota_types
0775      * since they needn't be set if quota is not supported at all.
0776      */
0777     if (!sb->s_qcop)
0778         return -ENOSYS;
0779     if (!(sb->s_quota_types & (1 << type)))
0780         return -EINVAL;
0781 
0782     ret = check_quotactl_permission(sb, type, cmd, id);
0783     if (ret < 0)
0784         return ret;
0785 
0786     switch (cmd) {
0787     case Q_QUOTAON:
0788         return quota_quotaon(sb, type, id, path);
0789     case Q_QUOTAOFF:
0790         return quota_quotaoff(sb, type);
0791     case Q_GETFMT:
0792         return quota_getfmt(sb, type, addr);
0793     case Q_GETINFO:
0794         return quota_getinfo(sb, type, addr);
0795     case Q_SETINFO:
0796         return quota_setinfo(sb, type, addr);
0797     case Q_GETQUOTA:
0798         return quota_getquota(sb, type, id, addr);
0799     case Q_GETNEXTQUOTA:
0800         return quota_getnextquota(sb, type, id, addr);
0801     case Q_SETQUOTA:
0802         return quota_setquota(sb, type, id, addr);
0803     case Q_SYNC:
0804         if (!sb->s_qcop->quota_sync)
0805             return -ENOSYS;
0806         return sb->s_qcop->quota_sync(sb, type);
0807     case Q_XQUOTAON:
0808         return quota_enable(sb, addr);
0809     case Q_XQUOTAOFF:
0810         return quota_disable(sb, addr);
0811     case Q_XQUOTARM:
0812         return quota_rmxquota(sb, addr);
0813     case Q_XGETQSTAT:
0814         return quota_getxstate(sb, type, addr);
0815     case Q_XGETQSTATV:
0816         return quota_getxstatev(sb, type, addr);
0817     case Q_XSETQLIM:
0818         return quota_setxquota(sb, type, id, addr);
0819     case Q_XGETQUOTA:
0820         return quota_getxquota(sb, type, id, addr);
0821     case Q_XGETNEXTQUOTA:
0822         return quota_getnextxquota(sb, type, id, addr);
0823     case Q_XQUOTASYNC:
0824         if (sb_rdonly(sb))
0825             return -EROFS;
0826         /* XFS quotas are fully coherent now, making this call a noop */
0827         return 0;
0828     default:
0829         return -EINVAL;
0830     }
0831 }
0832 
0833 /* Return 1 if 'cmd' will block on frozen filesystem */
0834 static int quotactl_cmd_write(int cmd)
0835 {
0836     /*
0837      * We cannot allow Q_GETQUOTA and Q_GETNEXTQUOTA without write access
0838      * as dquot_acquire() may allocate space for new structure and OCFS2
0839      * needs to increment on-disk use count.
0840      */
0841     switch (cmd) {
0842     case Q_GETFMT:
0843     case Q_GETINFO:
0844     case Q_SYNC:
0845     case Q_XGETQSTAT:
0846     case Q_XGETQSTATV:
0847     case Q_XGETQUOTA:
0848     case Q_XGETNEXTQUOTA:
0849     case Q_XQUOTASYNC:
0850         return 0;
0851     }
0852     return 1;
0853 }
0854 
0855 /* Return true if quotactl command is manipulating quota on/off state */
0856 static bool quotactl_cmd_onoff(int cmd)
0857 {
0858     return (cmd == Q_QUOTAON) || (cmd == Q_QUOTAOFF) ||
0859          (cmd == Q_XQUOTAON) || (cmd == Q_XQUOTAOFF);
0860 }
0861 
0862 /*
0863  * look up a superblock on which quota ops will be performed
0864  * - use the name of a block device to find the superblock thereon
0865  */
0866 static struct super_block *quotactl_block(const char __user *special, int cmd)
0867 {
0868 #ifdef CONFIG_BLOCK
0869     struct super_block *sb;
0870     struct filename *tmp = getname(special);
0871     bool excl = false, thawed = false;
0872     int error;
0873     dev_t dev;
0874 
0875     if (IS_ERR(tmp))
0876         return ERR_CAST(tmp);
0877     error = lookup_bdev(tmp->name, &dev);
0878     putname(tmp);
0879     if (error)
0880         return ERR_PTR(error);
0881 
0882     if (quotactl_cmd_onoff(cmd)) {
0883         excl = true;
0884         thawed = true;
0885     } else if (quotactl_cmd_write(cmd)) {
0886         thawed = true;
0887     }
0888 
0889 retry:
0890     sb = user_get_super(dev, excl);
0891     if (!sb)
0892         return ERR_PTR(-ENODEV);
0893     if (thawed && sb->s_writers.frozen != SB_UNFROZEN) {
0894         if (excl)
0895             up_write(&sb->s_umount);
0896         else
0897             up_read(&sb->s_umount);
0898         wait_event(sb->s_writers.wait_unfrozen,
0899                sb->s_writers.frozen == SB_UNFROZEN);
0900         put_super(sb);
0901         goto retry;
0902     }
0903     return sb;
0904 
0905 #else
0906     return ERR_PTR(-ENODEV);
0907 #endif
0908 }
0909 
0910 /*
0911  * This is the system call interface. This communicates with
0912  * the user-level programs. Currently this only supports diskquota
0913  * calls. Maybe we need to add the process quotas etc. in the future,
0914  * but we probably should use rlimits for that.
0915  */
0916 SYSCALL_DEFINE4(quotactl, unsigned int, cmd, const char __user *, special,
0917         qid_t, id, void __user *, addr)
0918 {
0919     uint cmds, type;
0920     struct super_block *sb = NULL;
0921     struct path path, *pathp = NULL;
0922     int ret;
0923 
0924     cmds = cmd >> SUBCMDSHIFT;
0925     type = cmd & SUBCMDMASK;
0926 
0927     if (type >= MAXQUOTAS)
0928         return -EINVAL;
0929 
0930     /*
0931      * As a special case Q_SYNC can be called without a specific device.
0932      * It will iterate all superblocks that have quota enabled and call
0933      * the sync action on each of them.
0934      */
0935     if (!special) {
0936         if (cmds == Q_SYNC)
0937             return quota_sync_all(type);
0938         return -ENODEV;
0939     }
0940 
0941     /*
0942      * Path for quotaon has to be resolved before grabbing superblock
0943      * because that gets s_umount sem which is also possibly needed by path
0944      * resolution (think about autofs) and thus deadlocks could arise.
0945      */
0946     if (cmds == Q_QUOTAON) {
0947         ret = user_path_at(AT_FDCWD, addr, LOOKUP_FOLLOW|LOOKUP_AUTOMOUNT, &path);
0948         if (ret)
0949             pathp = ERR_PTR(ret);
0950         else
0951             pathp = &path;
0952     }
0953 
0954     sb = quotactl_block(special, cmds);
0955     if (IS_ERR(sb)) {
0956         ret = PTR_ERR(sb);
0957         goto out;
0958     }
0959 
0960     ret = do_quotactl(sb, type, cmds, id, addr, pathp);
0961 
0962     if (!quotactl_cmd_onoff(cmds))
0963         drop_super(sb);
0964     else
0965         drop_super_exclusive(sb);
0966 out:
0967     if (pathp && !IS_ERR(pathp))
0968         path_put(pathp);
0969     return ret;
0970 }
0971 
0972 SYSCALL_DEFINE4(quotactl_fd, unsigned int, fd, unsigned int, cmd,
0973         qid_t, id, void __user *, addr)
0974 {
0975     struct super_block *sb;
0976     unsigned int cmds = cmd >> SUBCMDSHIFT;
0977     unsigned int type = cmd & SUBCMDMASK;
0978     struct fd f;
0979     int ret;
0980 
0981     f = fdget_raw(fd);
0982     if (!f.file)
0983         return -EBADF;
0984 
0985     ret = -EINVAL;
0986     if (type >= MAXQUOTAS)
0987         goto out;
0988 
0989     if (quotactl_cmd_write(cmds)) {
0990         ret = mnt_want_write(f.file->f_path.mnt);
0991         if (ret)
0992             goto out;
0993     }
0994 
0995     sb = f.file->f_path.mnt->mnt_sb;
0996     if (quotactl_cmd_onoff(cmds))
0997         down_write(&sb->s_umount);
0998     else
0999         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);
1010 out:
1011     fdput(f);
1012     return ret;
1013 }
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