/* * Quota code necessary even when VFS quota support is not compiled * into the kernel. The interesting stuff is over in dquot.c, here * we have symbols for initial quotactl(2) handling, the sysctl(2) * variables, etc - things needed even when quota support disabled. */ #include <linux/fs.h> #include <linux/namei.h> #include <linux/slab.h> #include <asm/current.h> #include <linux/uaccess.h> #include <linux/kernel.h> #include <linux/security.h> #include <linux/syscalls.h> #include <linux/capability.h> #include <linux/quotaops.h> #include <linux/types.h> #include <linux/writeback.h> static int check_quotactl_permission(struct super_block *sb, int type, int cmd, qid_t id) { switch (cmd) { /* these commands do not require any special privilegues */ case Q_GETFMT: case Q_SYNC: case Q_GETINFO: case Q_XGETQSTAT: case Q_XGETQSTATV: case Q_XQUOTASYNC: break; /* allow to query information for dquots we "own" */ case Q_GETQUOTA: case Q_XGETQUOTA: if ((type == USRQUOTA && uid_eq(current_euid(), make_kuid(current_user_ns(), id))) || (type == GRPQUOTA && in_egroup_p(make_kgid(current_user_ns(), id)))) break; /*FALLTHROUGH*/ default: if (!capable(CAP_SYS_ADMIN)) return -EPERM; } return security_quotactl(cmd, type, id, sb); } static void quota_sync_one(struct super_block *sb, void *arg) { int type = *(int *)arg; if (sb->s_qcop && sb->s_qcop->quota_sync && (sb->s_quota_types & (1 << type))) sb->s_qcop->quota_sync(sb, type); } static int quota_sync_all(int type) { int ret; if (type >= MAXQUOTAS) return -EINVAL; ret = security_quotactl(Q_SYNC, type, 0, NULL); if (!ret) iterate_supers(quota_sync_one, &type); return ret; } unsigned int qtype_enforce_flag(int type) { switch (type) { case USRQUOTA: return FS_QUOTA_UDQ_ENFD; case GRPQUOTA: return FS_QUOTA_GDQ_ENFD; case PRJQUOTA: return FS_QUOTA_PDQ_ENFD; } return 0; } static int quota_quotaon(struct super_block *sb, int type, qid_t id, const struct path *path) { if (!sb->s_qcop->quota_on && !sb->s_qcop->quota_enable) return -ENOSYS; if (sb->s_qcop->quota_enable) return sb->s_qcop->quota_enable(sb, qtype_enforce_flag(type)); if (IS_ERR(path)) return PTR_ERR(path); return sb->s_qcop->quota_on(sb, type, id, path); } static int quota_quotaoff(struct super_block *sb, int type) { if (!sb->s_qcop->quota_off && !sb->s_qcop->quota_disable) return -ENOSYS; if (sb->s_qcop->quota_disable) return sb->s_qcop->quota_disable(sb, qtype_enforce_flag(type)); return sb->s_qcop->quota_off(sb, type); } static int quota_getfmt(struct super_block *sb, int type, void __user *addr) { __u32 fmt; if (!sb_has_quota_active(sb, type)) return -ESRCH; fmt = sb_dqopt(sb)->info[type].dqi_format->qf_fmt_id; if (copy_to_user(addr, &fmt, sizeof(fmt))) return -EFAULT; return 0; } static int quota_getinfo(struct super_block *sb, int type, void __user *addr) { struct qc_state state; struct qc_type_state *tstate; struct if_dqinfo uinfo; int ret; /* This checks whether qc_state has enough entries... */ BUILD_BUG_ON(MAXQUOTAS > XQM_MAXQUOTAS); if (!sb->s_qcop->get_state) return -ENOSYS; ret = sb->s_qcop->get_state(sb, &state); if (ret) return ret; tstate = state.s_state + type; if (!(tstate->flags & QCI_ACCT_ENABLED)) return -ESRCH; memset(&uinfo, 0, sizeof(uinfo)); uinfo.dqi_bgrace = tstate->spc_timelimit; uinfo.dqi_igrace = tstate->ino_timelimit; if (tstate->flags & QCI_SYSFILE) uinfo.dqi_flags |= DQF_SYS_FILE; if (tstate->flags & QCI_ROOT_SQUASH) uinfo.dqi_flags |= DQF_ROOT_SQUASH; uinfo.dqi_valid = IIF_ALL; if (copy_to_user(addr, &uinfo, sizeof(uinfo))) return -EFAULT; return 0; } static int quota_setinfo(struct super_block *sb, int type, void __user *addr) { struct if_dqinfo info; struct qc_info qinfo; if (copy_from_user(&info, addr, sizeof(info))) return -EFAULT; if (!sb->s_qcop->set_info) return -ENOSYS; if (info.dqi_valid & ~(IIF_FLAGS | IIF_BGRACE | IIF_IGRACE)) return -EINVAL; memset(&qinfo, 0, sizeof(qinfo)); if (info.dqi_valid & IIF_FLAGS) { if (info.dqi_flags & ~DQF_SETINFO_MASK) return -EINVAL; if (info.dqi_flags & DQF_ROOT_SQUASH) qinfo.i_flags |= QCI_ROOT_SQUASH; qinfo.i_fieldmask |= QC_FLAGS; } if (info.dqi_valid & IIF_BGRACE) { qinfo.i_spc_timelimit = info.dqi_bgrace; qinfo.i_fieldmask |= QC_SPC_TIMER; } if (info.dqi_valid & IIF_IGRACE) { qinfo.i_ino_timelimit = info.dqi_igrace; qinfo.i_fieldmask |= QC_INO_TIMER; } return sb->s_qcop->set_info(sb, type, &qinfo); } static inline qsize_t qbtos(qsize_t blocks) { return blocks << QIF_DQBLKSIZE_BITS; } static inline qsize_t stoqb(qsize_t space) { return (space + QIF_DQBLKSIZE - 1) >> QIF_DQBLKSIZE_BITS; } static void copy_to_if_dqblk(struct if_dqblk *dst, struct qc_dqblk *src) { memset(dst, 0, sizeof(*dst)); dst->dqb_bhardlimit = stoqb(src->d_spc_hardlimit); dst->dqb_bsoftlimit = stoqb(src->d_spc_softlimit); dst->dqb_curspace = src->d_space; dst->dqb_ihardlimit = src->d_ino_hardlimit; dst->dqb_isoftlimit = src->d_ino_softlimit; dst->dqb_curinodes = src->d_ino_count; dst->dqb_btime = src->d_spc_timer; dst->dqb_itime = src->d_ino_timer; dst->dqb_valid = QIF_ALL; } static int quota_getquota(struct super_block *sb, int type, qid_t id, void __user *addr) { struct kqid qid; struct qc_dqblk fdq; struct if_dqblk idq; int ret; if (!sb->s_qcop->get_dqblk) return -ENOSYS; qid = make_kqid(current_user_ns(), type, id); if (!qid_has_mapping(sb->s_user_ns, qid)) return -EINVAL; ret = sb->s_qcop->get_dqblk(sb, qid, &fdq); if (ret) return ret; copy_to_if_dqblk(&idq, &fdq); if (copy_to_user(addr, &idq, sizeof(idq))) return -EFAULT; return 0; } /* * Return quota for next active quota >= this id, if any exists, * otherwise return -ENOENT via ->get_nextdqblk */ static int quota_getnextquota(struct super_block *sb, int type, qid_t id, void __user *addr) { struct kqid qid; struct qc_dqblk fdq; struct if_nextdqblk idq; int ret; if (!sb->s_qcop->get_nextdqblk) return -ENOSYS; qid = make_kqid(current_user_ns(), type, id); if (!qid_has_mapping(sb->s_user_ns, qid)) return -EINVAL; ret = sb->s_qcop->get_nextdqblk(sb, &qid, &fdq); if (ret) return ret; /* struct if_nextdqblk is a superset of struct if_dqblk */ copy_to_if_dqblk((struct if_dqblk *)&idq, &fdq); idq.dqb_id = from_kqid(current_user_ns(), qid); if (copy_to_user(addr, &idq, sizeof(idq))) return -EFAULT; return 0; } static void copy_from_if_dqblk(struct qc_dqblk *dst, struct if_dqblk *src) { dst->d_spc_hardlimit = qbtos(src->dqb_bhardlimit); dst->d_spc_softlimit = qbtos(src->dqb_bsoftlimit); dst->d_space = src->dqb_curspace; dst->d_ino_hardlimit = src->dqb_ihardlimit; dst->d_ino_softlimit = src->dqb_isoftlimit; dst->d_ino_count = src->dqb_curinodes; dst->d_spc_timer = src->dqb_btime; dst->d_ino_timer = src->dqb_itime; dst->d_fieldmask = 0; if (src->dqb_valid & QIF_BLIMITS) dst->d_fieldmask |= QC_SPC_SOFT | QC_SPC_HARD; if (src->dqb_valid & QIF_SPACE) dst->d_fieldmask |= QC_SPACE; if (src->dqb_valid & QIF_ILIMITS) dst->d_fieldmask |= QC_INO_SOFT | QC_INO_HARD; if (src->dqb_valid & QIF_INODES) dst->d_fieldmask |= QC_INO_COUNT; if (src->dqb_valid & QIF_BTIME) dst->d_fieldmask |= QC_SPC_TIMER; if (src->dqb_valid & QIF_ITIME) dst->d_fieldmask |= QC_INO_TIMER; } static int quota_setquota(struct super_block *sb, int type, qid_t id, void __user *addr) { struct qc_dqblk fdq; struct if_dqblk idq; struct kqid qid; if (copy_from_user(&idq, addr, sizeof(idq))) return -EFAULT; if (!sb->s_qcop->set_dqblk) return -ENOSYS; qid = make_kqid(current_user_ns(), type, id); if (!qid_has_mapping(sb->s_user_ns, qid)) return -EINVAL; copy_from_if_dqblk(&fdq, &idq); return sb->s_qcop->set_dqblk(sb, qid, &fdq); } static int quota_enable(struct super_block *sb, void __user *addr) { __u32 flags; if (copy_from_user(&flags, addr, sizeof(flags))) return -EFAULT; if (!sb->s_qcop->quota_enable) return -ENOSYS; return sb->s_qcop->quota_enable(sb, flags); } static int quota_disable(struct super_block *sb, void __user *addr) { __u32 flags; if (copy_from_user(&flags, addr, sizeof(flags))) return -EFAULT; if (!sb->s_qcop->quota_disable) return -ENOSYS; return sb->s_qcop->quota_disable(sb, flags); } static int quota_state_to_flags(struct qc_state *state) { int flags = 0; if (state->s_state[USRQUOTA].flags & QCI_ACCT_ENABLED) flags |= FS_QUOTA_UDQ_ACCT; if (state->s_state[USRQUOTA].flags & QCI_LIMITS_ENFORCED) flags |= FS_QUOTA_UDQ_ENFD; if (state->s_state[GRPQUOTA].flags & QCI_ACCT_ENABLED) flags |= FS_QUOTA_GDQ_ACCT; if (state->s_state[GRPQUOTA].flags & QCI_LIMITS_ENFORCED) flags |= FS_QUOTA_GDQ_ENFD; if (state->s_state[PRJQUOTA].flags & QCI_ACCT_ENABLED) flags |= FS_QUOTA_PDQ_ACCT; if (state->s_state[PRJQUOTA].flags & QCI_LIMITS_ENFORCED) flags |= FS_QUOTA_PDQ_ENFD; return flags; } static int quota_getstate(struct super_block *sb, struct fs_quota_stat *fqs) { int type; struct qc_state state; int ret; memset(&state, 0, sizeof (struct qc_state)); ret = sb->s_qcop->get_state(sb, &state); if (ret < 0) return ret; memset(fqs, 0, sizeof(*fqs)); fqs->qs_version = FS_QSTAT_VERSION; fqs->qs_flags = quota_state_to_flags(&state); /* No quota enabled? */ if (!fqs->qs_flags) return -ENOSYS; fqs->qs_incoredqs = state.s_incoredqs; /* * GETXSTATE quotactl has space for just one set of time limits so * report them for the first enabled quota type */ for (type = 0; type < XQM_MAXQUOTAS; type++) if (state.s_state[type].flags & QCI_ACCT_ENABLED) break; BUG_ON(type == XQM_MAXQUOTAS); fqs->qs_btimelimit = state.s_state[type].spc_timelimit; fqs->qs_itimelimit = state.s_state[type].ino_timelimit; fqs->qs_rtbtimelimit = state.s_state[type].rt_spc_timelimit; fqs->qs_bwarnlimit = state.s_state[type].spc_warnlimit; fqs->qs_iwarnlimit = state.s_state[type].ino_warnlimit; /* Inodes may be allocated even if inactive; copy out if present */ if (state.s_state[USRQUOTA].ino) { fqs->qs_uquota.qfs_ino = state.s_state[USRQUOTA].ino; fqs->qs_uquota.qfs_nblks = state.s_state[USRQUOTA].blocks; fqs->qs_uquota.qfs_nextents = state.s_state[USRQUOTA].nextents; } if (state.s_state[GRPQUOTA].ino) { fqs->qs_gquota.qfs_ino = state.s_state[GRPQUOTA].ino; fqs->qs_gquota.qfs_nblks = state.s_state[GRPQUOTA].blocks; fqs->qs_gquota.qfs_nextents = state.s_state[GRPQUOTA].nextents; } if (state.s_state[PRJQUOTA].ino) { /* * Q_XGETQSTAT doesn't have room for both group and project * quotas. So, allow the project quota values to be copied out * only if there is no group quota information available. */ if (!(state.s_state[GRPQUOTA].flags & QCI_ACCT_ENABLED)) { fqs->qs_gquota.qfs_ino = state.s_state[PRJQUOTA].ino; fqs->qs_gquota.qfs_nblks = state.s_state[PRJQUOTA].blocks; fqs->qs_gquota.qfs_nextents = state.s_state[PRJQUOTA].nextents; } } return 0; } static int quota_getxstate(struct super_block *sb, void __user *addr) { struct fs_quota_stat fqs; int ret; if (!sb->s_qcop->get_state) return -ENOSYS; ret = quota_getstate(sb, &fqs); if (!ret && copy_to_user(addr, &fqs, sizeof(fqs))) return -EFAULT; return ret; } static int quota_getstatev(struct super_block *sb, struct fs_quota_statv *fqs) { int type; struct qc_state state; int ret; memset(&state, 0, sizeof (struct qc_state)); ret = sb->s_qcop->get_state(sb, &state); if (ret < 0) return ret; memset(fqs, 0, sizeof(*fqs)); fqs->qs_version = FS_QSTAT_VERSION; fqs->qs_flags = quota_state_to_flags(&state); /* No quota enabled? */ if (!fqs->qs_flags) return -ENOSYS; fqs->qs_incoredqs = state.s_incoredqs; /* * GETXSTATV quotactl has space for just one set of time limits so * report them for the first enabled quota type */ for (type = 0; type < XQM_MAXQUOTAS; type++) if (state.s_state[type].flags & QCI_ACCT_ENABLED) break; BUG_ON(type == XQM_MAXQUOTAS); fqs->qs_btimelimit = state.s_state[type].spc_timelimit; fqs->qs_itimelimit = state.s_state[type].ino_timelimit; fqs->qs_rtbtimelimit = state.s_state[type].rt_spc_timelimit; fqs->qs_bwarnlimit = state.s_state[type].spc_warnlimit; fqs->qs_iwarnlimit = state.s_state[type].ino_warnlimit; /* Inodes may be allocated even if inactive; copy out if present */ if (state.s_state[USRQUOTA].ino) { fqs->qs_uquota.qfs_ino = state.s_state[USRQUOTA].ino; fqs->qs_uquota.qfs_nblks = state.s_state[USRQUOTA].blocks; fqs->qs_uquota.qfs_nextents = state.s_state[USRQUOTA].nextents; } if (state.s_state[GRPQUOTA].ino) { fqs->qs_gquota.qfs_ino = state.s_state[GRPQUOTA].ino; fqs->qs_gquota.qfs_nblks = state.s_state[GRPQUOTA].blocks; fqs->qs_gquota.qfs_nextents = state.s_state[GRPQUOTA].nextents; } if (state.s_state[PRJQUOTA].ino) { fqs->qs_pquota.qfs_ino = state.s_state[PRJQUOTA].ino; fqs->qs_pquota.qfs_nblks = state.s_state[PRJQUOTA].blocks; fqs->qs_pquota.qfs_nextents = state.s_state[PRJQUOTA].nextents; } return 0; } static int quota_getxstatev(struct super_block *sb, void __user *addr) { struct fs_quota_statv fqs; int ret; if (!sb->s_qcop->get_state) return -ENOSYS; memset(&fqs, 0, sizeof(fqs)); if (copy_from_user(&fqs, addr, 1)) /* Just read qs_version */ return -EFAULT; /* If this kernel doesn't support user specified version, fail */ switch (fqs.qs_version) { case FS_QSTATV_VERSION1: break; default: return -EINVAL; } ret = quota_getstatev(sb, &fqs); if (!ret && copy_to_user(addr, &fqs, sizeof(fqs))) return -EFAULT; return ret; } /* * XFS defines BBTOB and BTOBB macros inside fs/xfs/ and we cannot move them * out of there as xfsprogs rely on definitions being in that header file. So * just define same functions here for quota purposes. */ #define XFS_BB_SHIFT 9 static inline u64 quota_bbtob(u64 blocks) { return blocks << XFS_BB_SHIFT; } static inline u64 quota_btobb(u64 bytes) { return (bytes + (1 << XFS_BB_SHIFT) - 1) >> XFS_BB_SHIFT; } static void copy_from_xfs_dqblk(struct qc_dqblk *dst, struct fs_disk_quota *src) { dst->d_spc_hardlimit = quota_bbtob(src->d_blk_hardlimit); dst->d_spc_softlimit = quota_bbtob(src->d_blk_softlimit); dst->d_ino_hardlimit = src->d_ino_hardlimit; dst->d_ino_softlimit = src->d_ino_softlimit; dst->d_space = quota_bbtob(src->d_bcount); dst->d_ino_count = src->d_icount; dst->d_ino_timer = src->d_itimer; dst->d_spc_timer = src->d_btimer; dst->d_ino_warns = src->d_iwarns; dst->d_spc_warns = src->d_bwarns; dst->d_rt_spc_hardlimit = quota_bbtob(src->d_rtb_hardlimit); dst->d_rt_spc_softlimit = quota_bbtob(src->d_rtb_softlimit); dst->d_rt_space = quota_bbtob(src->d_rtbcount); dst->d_rt_spc_timer = src->d_rtbtimer; dst->d_rt_spc_warns = src->d_rtbwarns; dst->d_fieldmask = 0; if (src->d_fieldmask & FS_DQ_ISOFT) dst->d_fieldmask |= QC_INO_SOFT; if (src->d_fieldmask & FS_DQ_IHARD) dst->d_fieldmask |= QC_INO_HARD; if (src->d_fieldmask & FS_DQ_BSOFT) dst->d_fieldmask |= QC_SPC_SOFT; if (src->d_fieldmask & FS_DQ_BHARD) dst->d_fieldmask |= QC_SPC_HARD; if (src->d_fieldmask & FS_DQ_RTBSOFT) dst->d_fieldmask |= QC_RT_SPC_SOFT; if (src->d_fieldmask & FS_DQ_RTBHARD) dst->d_fieldmask |= QC_RT_SPC_HARD; if (src->d_fieldmask & FS_DQ_BTIMER) dst->d_fieldmask |= QC_SPC_TIMER; if (src->d_fieldmask & FS_DQ_ITIMER) dst->d_fieldmask |= QC_INO_TIMER; if (src->d_fieldmask & FS_DQ_RTBTIMER) dst->d_fieldmask |= QC_RT_SPC_TIMER; if (src->d_fieldmask & FS_DQ_BWARNS) dst->d_fieldmask |= QC_SPC_WARNS; if (src->d_fieldmask & FS_DQ_IWARNS) dst->d_fieldmask |= QC_INO_WARNS; if (src->d_fieldmask & FS_DQ_RTBWARNS) dst->d_fieldmask |= QC_RT_SPC_WARNS; if (src->d_fieldmask & FS_DQ_BCOUNT) dst->d_fieldmask |= QC_SPACE; if (src->d_fieldmask & FS_DQ_ICOUNT) dst->d_fieldmask |= QC_INO_COUNT; if (src->d_fieldmask & FS_DQ_RTBCOUNT) dst->d_fieldmask |= QC_RT_SPACE; } static void copy_qcinfo_from_xfs_dqblk(struct qc_info *dst, struct fs_disk_quota *src) { memset(dst, 0, sizeof(*dst)); dst->i_spc_timelimit = src->d_btimer; dst->i_ino_timelimit = src->d_itimer; dst->i_rt_spc_timelimit = src->d_rtbtimer; dst->i_ino_warnlimit = src->d_iwarns; dst->i_spc_warnlimit = src->d_bwarns; dst->i_rt_spc_warnlimit = src->d_rtbwarns; if (src->d_fieldmask & FS_DQ_BWARNS) dst->i_fieldmask |= QC_SPC_WARNS; if (src->d_fieldmask & FS_DQ_IWARNS) dst->i_fieldmask |= QC_INO_WARNS; if (src->d_fieldmask & FS_DQ_RTBWARNS) dst->i_fieldmask |= QC_RT_SPC_WARNS; if (src->d_fieldmask & FS_DQ_BTIMER) dst->i_fieldmask |= QC_SPC_TIMER; if (src->d_fieldmask & FS_DQ_ITIMER) dst->i_fieldmask |= QC_INO_TIMER; if (src->d_fieldmask & FS_DQ_RTBTIMER) dst->i_fieldmask |= QC_RT_SPC_TIMER; } static int quota_setxquota(struct super_block *sb, int type, qid_t id, void __user *addr) { struct fs_disk_quota fdq; struct qc_dqblk qdq; struct kqid qid; if (copy_from_user(&fdq, addr, sizeof(fdq))) return -EFAULT; if (!sb->s_qcop->set_dqblk) return -ENOSYS; qid = make_kqid(current_user_ns(), type, id); if (!qid_has_mapping(sb->s_user_ns, qid)) return -EINVAL; /* Are we actually setting timer / warning limits for all users? */ if (from_kqid(sb->s_user_ns, qid) == 0 && fdq.d_fieldmask & (FS_DQ_WARNS_MASK | FS_DQ_TIMER_MASK)) { struct qc_info qinfo; int ret; if (!sb->s_qcop->set_info) return -EINVAL; copy_qcinfo_from_xfs_dqblk(&qinfo, &fdq); ret = sb->s_qcop->set_info(sb, type, &qinfo); if (ret) return ret; /* These are already done */ fdq.d_fieldmask &= ~(FS_DQ_WARNS_MASK | FS_DQ_TIMER_MASK); } copy_from_xfs_dqblk(&qdq, &fdq); return sb->s_qcop->set_dqblk(sb, qid, &qdq); } static void copy_to_xfs_dqblk(struct fs_disk_quota *dst, struct qc_dqblk *src, int type, qid_t id) { memset(dst, 0, sizeof(*dst)); dst->d_version = FS_DQUOT_VERSION; dst->d_id = id; if (type == USRQUOTA) dst->d_flags = FS_USER_QUOTA; else if (type == PRJQUOTA) dst->d_flags = FS_PROJ_QUOTA; else dst->d_flags = FS_GROUP_QUOTA; dst->d_blk_hardlimit = quota_btobb(src->d_spc_hardlimit); dst->d_blk_softlimit = quota_btobb(src->d_spc_softlimit); dst->d_ino_hardlimit = src->d_ino_hardlimit; dst->d_ino_softlimit = src->d_ino_softlimit; dst->d_bcount = quota_btobb(src->d_space); dst->d_icount = src->d_ino_count; dst->d_itimer = src->d_ino_timer; dst->d_btimer = src->d_spc_timer; dst->d_iwarns = src->d_ino_warns; dst->d_bwarns = src->d_spc_warns; dst->d_rtb_hardlimit = quota_btobb(src->d_rt_spc_hardlimit); dst->d_rtb_softlimit = quota_btobb(src->d_rt_spc_softlimit); dst->d_rtbcount = quota_btobb(src->d_rt_space); dst->d_rtbtimer = src->d_rt_spc_timer; dst->d_rtbwarns = src->d_rt_spc_warns; } static int quota_getxquota(struct super_block *sb, int type, qid_t id, void __user *addr) { struct fs_disk_quota fdq; struct qc_dqblk qdq; struct kqid qid; int ret; if (!sb->s_qcop->get_dqblk) return -ENOSYS; qid = make_kqid(current_user_ns(), type, id); if (!qid_has_mapping(sb->s_user_ns, qid)) return -EINVAL; ret = sb->s_qcop->get_dqblk(sb, qid, &qdq); if (ret) return ret; copy_to_xfs_dqblk(&fdq, &qdq, type, id); if (copy_to_user(addr, &fdq, sizeof(fdq))) return -EFAULT; return ret; } /* * Return quota for next active quota >= this id, if any exists, * otherwise return -ENOENT via ->get_nextdqblk. */ static int quota_getnextxquota(struct super_block *sb, int type, qid_t id, void __user *addr) { struct fs_disk_quota fdq; struct qc_dqblk qdq; struct kqid qid; qid_t id_out; int ret; if (!sb->s_qcop->get_nextdqblk) return -ENOSYS; qid = make_kqid(current_user_ns(), type, id); if (!qid_has_mapping(sb->s_user_ns, qid)) return -EINVAL; ret = sb->s_qcop->get_nextdqblk(sb, &qid, &qdq); if (ret) return ret; id_out = from_kqid(current_user_ns(), qid); copy_to_xfs_dqblk(&fdq, &qdq, type, id_out); if (copy_to_user(addr, &fdq, sizeof(fdq))) return -EFAULT; return ret; } static int quota_rmxquota(struct super_block *sb, void __user *addr) { __u32 flags; if (copy_from_user(&flags, addr, sizeof(flags))) return -EFAULT; if (!sb->s_qcop->rm_xquota) return -ENOSYS; return sb->s_qcop->rm_xquota(sb, flags); } /* Copy parameters and call proper function */ static int do_quotactl(struct super_block *sb, int type, int cmd, qid_t id, void __user *addr, const struct path *path) { int ret; if (type >= (XQM_COMMAND(cmd) ? XQM_MAXQUOTAS : MAXQUOTAS)) return -EINVAL; /* * Quota not supported on this fs? Check this before s_quota_types * since they needn't be set if quota is not supported at all. */ if (!sb->s_qcop) return -ENOSYS; if (!(sb->s_quota_types & (1 << type))) return -EINVAL; ret = check_quotactl_permission(sb, type, cmd, id); if (ret < 0) return ret; switch (cmd) { case Q_QUOTAON: return quota_quotaon(sb, type, id, path); case Q_QUOTAOFF: return quota_quotaoff(sb, type); case Q_GETFMT: return quota_getfmt(sb, type, addr); case Q_GETINFO: return quota_getinfo(sb, type, addr); case Q_SETINFO: return quota_setinfo(sb, type, addr); case Q_GETQUOTA: return quota_getquota(sb, type, id, addr); case Q_GETNEXTQUOTA: return quota_getnextquota(sb, type, id, addr); case Q_SETQUOTA: return quota_setquota(sb, type, id, addr); case Q_SYNC: if (!sb->s_qcop->quota_sync) return -ENOSYS; return sb->s_qcop->quota_sync(sb, type); case Q_XQUOTAON: return quota_enable(sb, addr); case Q_XQUOTAOFF: return quota_disable(sb, addr); case Q_XQUOTARM: return quota_rmxquota(sb, addr); case Q_XGETQSTAT: return quota_getxstate(sb, addr); case Q_XGETQSTATV: return quota_getxstatev(sb, addr); case Q_XSETQLIM: return quota_setxquota(sb, type, id, addr); case Q_XGETQUOTA: return quota_getxquota(sb, type, id, addr); case Q_XGETNEXTQUOTA: return quota_getnextxquota(sb, type, id, addr); case Q_XQUOTASYNC: if (sb->s_flags & MS_RDONLY) return -EROFS; /* XFS quotas are fully coherent now, making this call a noop */ return 0; default: return -EINVAL; } } #ifdef CONFIG_BLOCK /* Return 1 if 'cmd' will block on frozen filesystem */ static int quotactl_cmd_write(int cmd) { /* * We cannot allow Q_GETQUOTA and Q_GETNEXTQUOTA without write access * as dquot_acquire() may allocate space for new structure and OCFS2 * needs to increment on-disk use count. */ switch (cmd) { case Q_GETFMT: case Q_GETINFO: case Q_SYNC: case Q_XGETQSTAT: case Q_XGETQSTATV: case Q_XGETQUOTA: case Q_XGETNEXTQUOTA: case Q_XQUOTASYNC: return 0; } return 1; } #endif /* CONFIG_BLOCK */ /* Return true if quotactl command is manipulating quota on/off state */ static bool quotactl_cmd_onoff(int cmd) { return (cmd == Q_QUOTAON) || (cmd == Q_QUOTAOFF); } /* * look up a superblock on which quota ops will be performed * - use the name of a block device to find the superblock thereon */ static struct super_block *quotactl_block(const char __user *special, int cmd) { #ifdef CONFIG_BLOCK struct block_device *bdev; struct super_block *sb; struct filename *tmp = getname(special); if (IS_ERR(tmp)) return ERR_CAST(tmp); bdev = lookup_bdev(tmp->name); putname(tmp); if (IS_ERR(bdev)) return ERR_CAST(bdev); if (quotactl_cmd_onoff(cmd)) sb = get_super_exclusive_thawed(bdev); else if (quotactl_cmd_write(cmd)) sb = get_super_thawed(bdev); else sb = get_super(bdev); bdput(bdev); if (!sb) return ERR_PTR(-ENODEV); return sb; #else return ERR_PTR(-ENODEV); #endif } /* * This is the system call interface. This communicates with * the user-level programs. Currently this only supports diskquota * calls. Maybe we need to add the process quotas etc. in the future, * but we probably should use rlimits for that. */ SYSCALL_DEFINE4(quotactl, unsigned int, cmd, const char __user *, special, qid_t, id, void __user *, addr) { uint cmds, type; struct super_block *sb = NULL; struct path path, *pathp = NULL; int ret; cmds = cmd >> SUBCMDSHIFT; type = cmd & SUBCMDMASK; /* * As a special case Q_SYNC can be called without a specific device. * It will iterate all superblocks that have quota enabled and call * the sync action on each of them. */ if (!special) { if (cmds == Q_SYNC) return quota_sync_all(type); return -ENODEV; } /* * Path for quotaon has to be resolved before grabbing superblock * because that gets s_umount sem which is also possibly needed by path * resolution (think about autofs) and thus deadlocks could arise. */ if (cmds == Q_QUOTAON) { ret = user_path_at(AT_FDCWD, addr, LOOKUP_FOLLOW|LOOKUP_AUTOMOUNT, &path); if (ret) pathp = ERR_PTR(ret); else pathp = &path; } sb = quotactl_block(special, cmds); if (IS_ERR(sb)) { ret = PTR_ERR(sb); goto out; } ret = do_quotactl(sb, type, cmds, id, addr, pathp); if (!quotactl_cmd_onoff(cmds)) drop_super(sb); else drop_super_exclusive(sb); out: if (pathp && !IS_ERR(pathp)) path_put(pathp); return ret; }