mirror of
https://github.com/torvalds/linux.git
synced 2024-11-16 00:52:01 +00:00
268157ba67
Wrap long lines, remove assignments from conditions, rewrite two overcomplicated for loops. Signed-off-by: Jan Kara <jack@suse.cz>
525 lines
12 KiB
C
525 lines
12 KiB
C
/*
|
|
* 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 <asm/uaccess.h>
|
|
#include <linux/compat.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/security.h>
|
|
#include <linux/syscalls.h>
|
|
#include <linux/buffer_head.h>
|
|
#include <linux/capability.h>
|
|
#include <linux/quotaops.h>
|
|
#include <linux/types.h>
|
|
|
|
/* Check validity of generic quotactl commands */
|
|
static int generic_quotactl_valid(struct super_block *sb, int type, int cmd,
|
|
qid_t id)
|
|
{
|
|
if (type >= MAXQUOTAS)
|
|
return -EINVAL;
|
|
if (!sb && cmd != Q_SYNC)
|
|
return -ENODEV;
|
|
/* Is operation supported? */
|
|
if (sb && !sb->s_qcop)
|
|
return -ENOSYS;
|
|
|
|
switch (cmd) {
|
|
case Q_GETFMT:
|
|
break;
|
|
case Q_QUOTAON:
|
|
if (!sb->s_qcop->quota_on)
|
|
return -ENOSYS;
|
|
break;
|
|
case Q_QUOTAOFF:
|
|
if (!sb->s_qcop->quota_off)
|
|
return -ENOSYS;
|
|
break;
|
|
case Q_SETINFO:
|
|
if (!sb->s_qcop->set_info)
|
|
return -ENOSYS;
|
|
break;
|
|
case Q_GETINFO:
|
|
if (!sb->s_qcop->get_info)
|
|
return -ENOSYS;
|
|
break;
|
|
case Q_SETQUOTA:
|
|
if (!sb->s_qcop->set_dqblk)
|
|
return -ENOSYS;
|
|
break;
|
|
case Q_GETQUOTA:
|
|
if (!sb->s_qcop->get_dqblk)
|
|
return -ENOSYS;
|
|
break;
|
|
case Q_SYNC:
|
|
if (sb && !sb->s_qcop->quota_sync)
|
|
return -ENOSYS;
|
|
break;
|
|
default:
|
|
return -EINVAL;
|
|
}
|
|
|
|
/* Is quota turned on for commands which need it? */
|
|
switch (cmd) {
|
|
case Q_GETFMT:
|
|
case Q_GETINFO:
|
|
case Q_SETINFO:
|
|
case Q_SETQUOTA:
|
|
case Q_GETQUOTA:
|
|
/* This is just an informative test so we are satisfied
|
|
* without the lock */
|
|
if (!sb_has_quota_active(sb, type))
|
|
return -ESRCH;
|
|
}
|
|
|
|
/* Check privileges */
|
|
if (cmd == Q_GETQUOTA) {
|
|
if (((type == USRQUOTA && current_euid() != id) ||
|
|
(type == GRPQUOTA && !in_egroup_p(id))) &&
|
|
!capable(CAP_SYS_ADMIN))
|
|
return -EPERM;
|
|
}
|
|
else if (cmd != Q_GETFMT && cmd != Q_SYNC && cmd != Q_GETINFO)
|
|
if (!capable(CAP_SYS_ADMIN))
|
|
return -EPERM;
|
|
|
|
return 0;
|
|
}
|
|
|
|
/* Check validity of XFS Quota Manager commands */
|
|
static int xqm_quotactl_valid(struct super_block *sb, int type, int cmd,
|
|
qid_t id)
|
|
{
|
|
if (type >= XQM_MAXQUOTAS)
|
|
return -EINVAL;
|
|
if (!sb)
|
|
return -ENODEV;
|
|
if (!sb->s_qcop)
|
|
return -ENOSYS;
|
|
|
|
switch (cmd) {
|
|
case Q_XQUOTAON:
|
|
case Q_XQUOTAOFF:
|
|
case Q_XQUOTARM:
|
|
if (!sb->s_qcop->set_xstate)
|
|
return -ENOSYS;
|
|
break;
|
|
case Q_XGETQSTAT:
|
|
if (!sb->s_qcop->get_xstate)
|
|
return -ENOSYS;
|
|
break;
|
|
case Q_XSETQLIM:
|
|
if (!sb->s_qcop->set_xquota)
|
|
return -ENOSYS;
|
|
break;
|
|
case Q_XGETQUOTA:
|
|
if (!sb->s_qcop->get_xquota)
|
|
return -ENOSYS;
|
|
break;
|
|
case Q_XQUOTASYNC:
|
|
if (!sb->s_qcop->quota_sync)
|
|
return -ENOSYS;
|
|
break;
|
|
default:
|
|
return -EINVAL;
|
|
}
|
|
|
|
/* Check privileges */
|
|
if (cmd == Q_XGETQUOTA) {
|
|
if (((type == XQM_USRQUOTA && current_euid() != id) ||
|
|
(type == XQM_GRPQUOTA && !in_egroup_p(id))) &&
|
|
!capable(CAP_SYS_ADMIN))
|
|
return -EPERM;
|
|
} else if (cmd != Q_XGETQSTAT && cmd != Q_XQUOTASYNC) {
|
|
if (!capable(CAP_SYS_ADMIN))
|
|
return -EPERM;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int check_quotactl_valid(struct super_block *sb, int type, int cmd,
|
|
qid_t id)
|
|
{
|
|
int error;
|
|
|
|
if (XQM_COMMAND(cmd))
|
|
error = xqm_quotactl_valid(sb, type, cmd, id);
|
|
else
|
|
error = generic_quotactl_valid(sb, type, cmd, id);
|
|
if (!error)
|
|
error = security_quotactl(cmd, type, id, sb);
|
|
return error;
|
|
}
|
|
|
|
static void quota_sync_sb(struct super_block *sb, int type)
|
|
{
|
|
int cnt;
|
|
|
|
sb->s_qcop->quota_sync(sb, type);
|
|
|
|
if (sb_dqopt(sb)->flags & DQUOT_QUOTA_SYS_FILE)
|
|
return;
|
|
/* This is not very clever (and fast) but currently I don't know about
|
|
* any other simple way of getting quota data to disk and we must get
|
|
* them there for userspace to be visible... */
|
|
if (sb->s_op->sync_fs)
|
|
sb->s_op->sync_fs(sb, 1);
|
|
sync_blockdev(sb->s_bdev);
|
|
|
|
/*
|
|
* Now when everything is written we can discard the pagecache so
|
|
* that userspace sees the changes.
|
|
*/
|
|
mutex_lock(&sb_dqopt(sb)->dqonoff_mutex);
|
|
for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
|
|
if (type != -1 && cnt != type)
|
|
continue;
|
|
if (!sb_has_quota_active(sb, cnt))
|
|
continue;
|
|
mutex_lock_nested(&sb_dqopt(sb)->files[cnt]->i_mutex,
|
|
I_MUTEX_QUOTA);
|
|
truncate_inode_pages(&sb_dqopt(sb)->files[cnt]->i_data, 0);
|
|
mutex_unlock(&sb_dqopt(sb)->files[cnt]->i_mutex);
|
|
}
|
|
mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex);
|
|
}
|
|
|
|
void sync_dquots(struct super_block *sb, int type)
|
|
{
|
|
int cnt;
|
|
|
|
if (sb) {
|
|
if (sb->s_qcop->quota_sync)
|
|
quota_sync_sb(sb, type);
|
|
return;
|
|
}
|
|
|
|
spin_lock(&sb_lock);
|
|
restart:
|
|
list_for_each_entry(sb, &super_blocks, s_list) {
|
|
/* This test just improves performance so it needn't be
|
|
* reliable... */
|
|
for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
|
|
if (type != -1 && type != cnt)
|
|
continue;
|
|
if (!sb_has_quota_active(sb, cnt))
|
|
continue;
|
|
if (!info_dirty(&sb_dqopt(sb)->info[cnt]) &&
|
|
list_empty(&sb_dqopt(sb)->info[cnt].dqi_dirty_list))
|
|
continue;
|
|
break;
|
|
}
|
|
if (cnt == MAXQUOTAS)
|
|
continue;
|
|
sb->s_count++;
|
|
spin_unlock(&sb_lock);
|
|
down_read(&sb->s_umount);
|
|
if (sb->s_root && sb->s_qcop->quota_sync)
|
|
quota_sync_sb(sb, type);
|
|
up_read(&sb->s_umount);
|
|
spin_lock(&sb_lock);
|
|
if (__put_super_and_need_restart(sb))
|
|
goto restart;
|
|
}
|
|
spin_unlock(&sb_lock);
|
|
}
|
|
|
|
/* Copy parameters and call proper function */
|
|
static int do_quotactl(struct super_block *sb, int type, int cmd, qid_t id,
|
|
void __user *addr)
|
|
{
|
|
int ret;
|
|
|
|
switch (cmd) {
|
|
case Q_QUOTAON: {
|
|
char *pathname;
|
|
|
|
pathname = getname(addr);
|
|
if (IS_ERR(pathname))
|
|
return PTR_ERR(pathname);
|
|
ret = sb->s_qcop->quota_on(sb, type, id, pathname, 0);
|
|
putname(pathname);
|
|
return ret;
|
|
}
|
|
case Q_QUOTAOFF:
|
|
return sb->s_qcop->quota_off(sb, type, 0);
|
|
|
|
case Q_GETFMT: {
|
|
__u32 fmt;
|
|
|
|
down_read(&sb_dqopt(sb)->dqptr_sem);
|
|
if (!sb_has_quota_active(sb, type)) {
|
|
up_read(&sb_dqopt(sb)->dqptr_sem);
|
|
return -ESRCH;
|
|
}
|
|
fmt = sb_dqopt(sb)->info[type].dqi_format->qf_fmt_id;
|
|
up_read(&sb_dqopt(sb)->dqptr_sem);
|
|
if (copy_to_user(addr, &fmt, sizeof(fmt)))
|
|
return -EFAULT;
|
|
return 0;
|
|
}
|
|
case Q_GETINFO: {
|
|
struct if_dqinfo info;
|
|
|
|
ret = sb->s_qcop->get_info(sb, type, &info);
|
|
if (ret)
|
|
return ret;
|
|
if (copy_to_user(addr, &info, sizeof(info)))
|
|
return -EFAULT;
|
|
return 0;
|
|
}
|
|
case Q_SETINFO: {
|
|
struct if_dqinfo info;
|
|
|
|
if (copy_from_user(&info, addr, sizeof(info)))
|
|
return -EFAULT;
|
|
return sb->s_qcop->set_info(sb, type, &info);
|
|
}
|
|
case Q_GETQUOTA: {
|
|
struct if_dqblk idq;
|
|
|
|
ret = sb->s_qcop->get_dqblk(sb, type, id, &idq);
|
|
if (ret)
|
|
return ret;
|
|
if (copy_to_user(addr, &idq, sizeof(idq)))
|
|
return -EFAULT;
|
|
return 0;
|
|
}
|
|
case Q_SETQUOTA: {
|
|
struct if_dqblk idq;
|
|
|
|
if (copy_from_user(&idq, addr, sizeof(idq)))
|
|
return -EFAULT;
|
|
return sb->s_qcop->set_dqblk(sb, type, id, &idq);
|
|
}
|
|
case Q_SYNC:
|
|
sync_dquots(sb, type);
|
|
return 0;
|
|
|
|
case Q_XQUOTAON:
|
|
case Q_XQUOTAOFF:
|
|
case Q_XQUOTARM: {
|
|
__u32 flags;
|
|
|
|
if (copy_from_user(&flags, addr, sizeof(flags)))
|
|
return -EFAULT;
|
|
return sb->s_qcop->set_xstate(sb, flags, cmd);
|
|
}
|
|
case Q_XGETQSTAT: {
|
|
struct fs_quota_stat fqs;
|
|
|
|
if ((ret = sb->s_qcop->get_xstate(sb, &fqs)))
|
|
return ret;
|
|
if (copy_to_user(addr, &fqs, sizeof(fqs)))
|
|
return -EFAULT;
|
|
return 0;
|
|
}
|
|
case Q_XSETQLIM: {
|
|
struct fs_disk_quota fdq;
|
|
|
|
if (copy_from_user(&fdq, addr, sizeof(fdq)))
|
|
return -EFAULT;
|
|
return sb->s_qcop->set_xquota(sb, type, id, &fdq);
|
|
}
|
|
case Q_XGETQUOTA: {
|
|
struct fs_disk_quota fdq;
|
|
|
|
ret = sb->s_qcop->get_xquota(sb, type, id, &fdq);
|
|
if (ret)
|
|
return ret;
|
|
if (copy_to_user(addr, &fdq, sizeof(fdq)))
|
|
return -EFAULT;
|
|
return 0;
|
|
}
|
|
case Q_XQUOTASYNC:
|
|
return sb->s_qcop->quota_sync(sb, type);
|
|
/* We never reach here unless validity check is broken */
|
|
default:
|
|
BUG();
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* 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)
|
|
{
|
|
#ifdef CONFIG_BLOCK
|
|
struct block_device *bdev;
|
|
struct super_block *sb;
|
|
char *tmp = getname(special);
|
|
|
|
if (IS_ERR(tmp))
|
|
return ERR_CAST(tmp);
|
|
bdev = lookup_bdev(tmp);
|
|
putname(tmp);
|
|
if (IS_ERR(bdev))
|
|
return ERR_CAST(bdev);
|
|
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;
|
|
int ret;
|
|
|
|
cmds = cmd >> SUBCMDSHIFT;
|
|
type = cmd & SUBCMDMASK;
|
|
|
|
if (cmds != Q_SYNC || special) {
|
|
sb = quotactl_block(special);
|
|
if (IS_ERR(sb))
|
|
return PTR_ERR(sb);
|
|
}
|
|
|
|
ret = check_quotactl_valid(sb, type, cmds, id);
|
|
if (ret >= 0)
|
|
ret = do_quotactl(sb, type, cmds, id, addr);
|
|
if (sb)
|
|
drop_super(sb);
|
|
|
|
return ret;
|
|
}
|
|
|
|
#if defined(CONFIG_COMPAT_FOR_U64_ALIGNMENT)
|
|
/*
|
|
* This code works only for 32 bit quota tools over 64 bit OS (x86_64, ia64)
|
|
* and is necessary due to alignment problems.
|
|
*/
|
|
struct compat_if_dqblk {
|
|
compat_u64 dqb_bhardlimit;
|
|
compat_u64 dqb_bsoftlimit;
|
|
compat_u64 dqb_curspace;
|
|
compat_u64 dqb_ihardlimit;
|
|
compat_u64 dqb_isoftlimit;
|
|
compat_u64 dqb_curinodes;
|
|
compat_u64 dqb_btime;
|
|
compat_u64 dqb_itime;
|
|
compat_uint_t dqb_valid;
|
|
};
|
|
|
|
/* XFS structures */
|
|
struct compat_fs_qfilestat {
|
|
compat_u64 dqb_bhardlimit;
|
|
compat_u64 qfs_nblks;
|
|
compat_uint_t qfs_nextents;
|
|
};
|
|
|
|
struct compat_fs_quota_stat {
|
|
__s8 qs_version;
|
|
__u16 qs_flags;
|
|
__s8 qs_pad;
|
|
struct compat_fs_qfilestat qs_uquota;
|
|
struct compat_fs_qfilestat qs_gquota;
|
|
compat_uint_t qs_incoredqs;
|
|
compat_int_t qs_btimelimit;
|
|
compat_int_t qs_itimelimit;
|
|
compat_int_t qs_rtbtimelimit;
|
|
__u16 qs_bwarnlimit;
|
|
__u16 qs_iwarnlimit;
|
|
};
|
|
|
|
asmlinkage long sys32_quotactl(unsigned int cmd, const char __user *special,
|
|
qid_t id, void __user *addr)
|
|
{
|
|
unsigned int cmds;
|
|
struct if_dqblk __user *dqblk;
|
|
struct compat_if_dqblk __user *compat_dqblk;
|
|
struct fs_quota_stat __user *fsqstat;
|
|
struct compat_fs_quota_stat __user *compat_fsqstat;
|
|
compat_uint_t data;
|
|
u16 xdata;
|
|
long ret;
|
|
|
|
cmds = cmd >> SUBCMDSHIFT;
|
|
|
|
switch (cmds) {
|
|
case Q_GETQUOTA:
|
|
dqblk = compat_alloc_user_space(sizeof(struct if_dqblk));
|
|
compat_dqblk = addr;
|
|
ret = sys_quotactl(cmd, special, id, dqblk);
|
|
if (ret)
|
|
break;
|
|
if (copy_in_user(compat_dqblk, dqblk, sizeof(*compat_dqblk)) ||
|
|
get_user(data, &dqblk->dqb_valid) ||
|
|
put_user(data, &compat_dqblk->dqb_valid))
|
|
ret = -EFAULT;
|
|
break;
|
|
case Q_SETQUOTA:
|
|
dqblk = compat_alloc_user_space(sizeof(struct if_dqblk));
|
|
compat_dqblk = addr;
|
|
ret = -EFAULT;
|
|
if (copy_in_user(dqblk, compat_dqblk, sizeof(*compat_dqblk)) ||
|
|
get_user(data, &compat_dqblk->dqb_valid) ||
|
|
put_user(data, &dqblk->dqb_valid))
|
|
break;
|
|
ret = sys_quotactl(cmd, special, id, dqblk);
|
|
break;
|
|
case Q_XGETQSTAT:
|
|
fsqstat = compat_alloc_user_space(sizeof(struct fs_quota_stat));
|
|
compat_fsqstat = addr;
|
|
ret = sys_quotactl(cmd, special, id, fsqstat);
|
|
if (ret)
|
|
break;
|
|
ret = -EFAULT;
|
|
/* Copying qs_version, qs_flags, qs_pad */
|
|
if (copy_in_user(compat_fsqstat, fsqstat,
|
|
offsetof(struct compat_fs_quota_stat, qs_uquota)))
|
|
break;
|
|
/* Copying qs_uquota */
|
|
if (copy_in_user(&compat_fsqstat->qs_uquota,
|
|
&fsqstat->qs_uquota,
|
|
sizeof(compat_fsqstat->qs_uquota)) ||
|
|
get_user(data, &fsqstat->qs_uquota.qfs_nextents) ||
|
|
put_user(data, &compat_fsqstat->qs_uquota.qfs_nextents))
|
|
break;
|
|
/* Copying qs_gquota */
|
|
if (copy_in_user(&compat_fsqstat->qs_gquota,
|
|
&fsqstat->qs_gquota,
|
|
sizeof(compat_fsqstat->qs_gquota)) ||
|
|
get_user(data, &fsqstat->qs_gquota.qfs_nextents) ||
|
|
put_user(data, &compat_fsqstat->qs_gquota.qfs_nextents))
|
|
break;
|
|
/* Copying the rest */
|
|
if (copy_in_user(&compat_fsqstat->qs_incoredqs,
|
|
&fsqstat->qs_incoredqs,
|
|
sizeof(struct compat_fs_quota_stat) -
|
|
offsetof(struct compat_fs_quota_stat, qs_incoredqs)) ||
|
|
get_user(xdata, &fsqstat->qs_iwarnlimit) ||
|
|
put_user(xdata, &compat_fsqstat->qs_iwarnlimit))
|
|
break;
|
|
ret = 0;
|
|
break;
|
|
default:
|
|
ret = sys_quotactl(cmd, special, id, addr);
|
|
}
|
|
return ret;
|
|
}
|
|
#endif
|