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linux/fs/quota/quota.c
Jan Kara ccf370e43e quota: Forbid Q_GETQUOTA and Q_GETNEXTQUOTA for frozen filesystem 
Commit 7955118eaf (quota: Allow Q_GETQUOTA for frozen filesystem)
allowed Q_GETQUOTA call for frozen filesystem. It makes sense on the
first look but zero-day testing has shown that with this change ext4
warns about starting a transaction for frozen filesystem. This happens
because ext4_acquire_dquot() prepares for allocating space for new quota
structure. Although it would be possible to implement Q_GETQUOTA for
ext4 without allocating space for non-existent structures, the matter
further complicates because OCFS2 needs to update on-disk structure use
count when a new cluster node loads quota information from disk. So just
revert the change and forbid Q_GETQUOTA together with Q_GETNEXTQUOTA for
frozen filesystem. Add comment to quotactl_cmd_write() to save us from
repeating this excercise in a few years when I forget again.

Signed-off-by: Jan Kara <jack@suse.cz>
2016-02-18 14:03:03 +01:00

875 lines
24 KiB
C
Raw Blame History

/*
* 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,
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;
mutex_lock(&sb_dqopt(sb)->dqonoff_mutex);
if (!sb_has_quota_active(sb, type)) {
mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex);
return -ESRCH;
}
fmt = sb_dqopt(sb)->info[type].dqi_format->qf_fmt_id;
mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex);
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_valid(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_valid(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_valid(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;
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;
if (state.s_state[USRQUOTA].flags & QCI_ACCT_ENABLED) {
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].flags & QCI_ACCT_ENABLED) {
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].flags & QCI_ACCT_ENABLED) {
/*
* 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;
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;
if (state.s_state[USRQUOTA].flags & QCI_ACCT_ENABLED) {
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].flags & QCI_ACCT_ENABLED) {
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].flags & QCI_ACCT_ENABLED) {
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_valid(qid))
return -EINVAL;
/* Are we actually setting timer / warning limits for all users? */
if (from_kqid(&init_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_valid(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_valid(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, 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 */
/*
* 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_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);
drop_super(sb);
out:
if (pathp && !IS_ERR(pathp))
path_put(pathp);
return ret;
}
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