[people/ms/linux.git] / fs / statfs.c

// SPDX-License-Identifier: GPL-2.0
#include <linux/syscalls.h>
#include <linux/export.h>
#include <linux/fs.h>
#include <linux/file.h>
#include <linux/mount.h>
#include <linux/namei.h>
#include <linux/statfs.h>
#include <linux/security.h>
#include <linux/uaccess.h>
#include <linux/compat.h>
#include "internal.h"

static int flags_by_mnt(int mnt_flags)
{
	int flags = 0;

	if (mnt_flags & MNT_READONLY)
		flags |= ST_RDONLY;
	if (mnt_flags & MNT_NOSUID)
		flags |= ST_NOSUID;
	if (mnt_flags & MNT_NODEV)
		flags |= ST_NODEV;
	if (mnt_flags & MNT_NOEXEC)
		flags |= ST_NOEXEC;
	if (mnt_flags & MNT_NOATIME)
		flags |= ST_NOATIME;
	if (mnt_flags & MNT_NODIRATIME)
		flags |= ST_NODIRATIME;
	if (mnt_flags & MNT_RELATIME)
		flags |= ST_RELATIME;
	if (mnt_flags & MNT_NOSYMFOLLOW)
		flags |= ST_NOSYMFOLLOW;
	return flags;
}

static int flags_by_sb(int s_flags)
{
	int flags = 0;
	if (s_flags & SB_SYNCHRONOUS)
		flags |= ST_SYNCHRONOUS;
	if (s_flags & SB_MANDLOCK)
		flags |= ST_MANDLOCK;
	if (s_flags & SB_RDONLY)
		flags |= ST_RDONLY;
	return flags;
}

static int calculate_f_flags(struct vfsmount *mnt)
{
	return ST_VALID | flags_by_mnt(mnt->mnt_flags) |
		flags_by_sb(mnt->mnt_sb->s_flags);
}

static int statfs_by_dentry(struct dentry *dentry, struct kstatfs *buf)
{
	int retval;

	if (!dentry->d_sb->s_op->statfs)
		return -ENOSYS;

	memset(buf, 0, sizeof(*buf));
	retval = security_sb_statfs(dentry);
	if (retval)
		return retval;
	retval = dentry->d_sb->s_op->statfs(dentry, buf);
	if (retval == 0 && buf->f_frsize == 0)
		buf->f_frsize = buf->f_bsize;
	return retval;
}

int vfs_get_fsid(struct dentry *dentry, __kernel_fsid_t *fsid)
{
	struct kstatfs st;
	int error;

	error = statfs_by_dentry(dentry, &st);
	if (error)
		return error;

	*fsid = st.f_fsid;
	return 0;
}
EXPORT_SYMBOL(vfs_get_fsid);

int vfs_statfs(const struct path *path, struct kstatfs *buf)
{
	int error;

	error = statfs_by_dentry(path->dentry, buf);
	if (!error)
		buf->f_flags = calculate_f_flags(path->mnt);
	return error;
}
EXPORT_SYMBOL(vfs_statfs);

int user_statfs(const char __user *pathname, struct kstatfs *st)
{
	struct path path;
	int error;
	unsigned int lookup_flags = LOOKUP_FOLLOW|LOOKUP_AUTOMOUNT;
retry:
	error = user_path_at(AT_FDCWD, pathname, lookup_flags, &path);
	if (!error) {
		error = vfs_statfs(&path, st);
		path_put(&path);
		if (retry_estale(error, lookup_flags)) {
			lookup_flags |= LOOKUP_REVAL;
			goto retry;
		}
	}
	return error;
}

int fd_statfs(int fd, struct kstatfs *st)
{
	struct fd f = fdget_raw(fd);
	int error = -EBADF;
	if (f.file) {
		error = vfs_statfs(&f.file->f_path, st);
		fdput(f);
	}
	return error;
}

static int do_statfs_native(struct kstatfs *st, struct statfs __user *p)
{
	struct statfs buf;

	if (sizeof(buf) == sizeof(*st))
		memcpy(&buf, st, sizeof(*st));
	else {
		if (sizeof buf.f_blocks == 4) {
			if ((st->f_blocks | st->f_bfree | st->f_bavail |
			     st->f_bsize | st->f_frsize) &
			    0xffffffff00000000ULL)
				return -EOVERFLOW;
			/*
			 * f_files and f_ffree may be -1; it's okay to stuff
			 * that into 32 bits
			 */
			if (st->f_files != -1 &&
			    (st->f_files & 0xffffffff00000000ULL))
				return -EOVERFLOW;
			if (st->f_ffree != -1 &&
			    (st->f_ffree & 0xffffffff00000000ULL))
				return -EOVERFLOW;
		}

		buf.f_type = st->f_type;
		buf.f_bsize = st->f_bsize;
		buf.f_blocks = st->f_blocks;
		buf.f_bfree = st->f_bfree;
		buf.f_bavail = st->f_bavail;
		buf.f_files = st->f_files;
		buf.f_ffree = st->f_ffree;
		buf.f_fsid = st->f_fsid;
		buf.f_namelen = st->f_namelen;
		buf.f_frsize = st->f_frsize;
		buf.f_flags = st->f_flags;
		memset(buf.f_spare, 0, sizeof(buf.f_spare));
	}
	if (copy_to_user(p, &buf, sizeof(buf)))
		return -EFAULT;
	return 0;
}

static int do_statfs64(struct kstatfs *st, struct statfs64 __user *p)
{
	struct statfs64 buf;
	if (sizeof(buf) == sizeof(*st))
		memcpy(&buf, st, sizeof(*st));
	else {
		buf.f_type = st->f_type;
		buf.f_bsize = st->f_bsize;
		buf.f_blocks = st->f_blocks;
		buf.f_bfree = st->f_bfree;
		buf.f_bavail = st->f_bavail;
		buf.f_files = st->f_files;
		buf.f_ffree = st->f_ffree;
		buf.f_fsid = st->f_fsid;
		buf.f_namelen = st->f_namelen;
		buf.f_frsize = st->f_frsize;
		buf.f_flags = st->f_flags;
		memset(buf.f_spare, 0, sizeof(buf.f_spare));
	}
	if (copy_to_user(p, &buf, sizeof(buf)))
		return -EFAULT;
	return 0;
}

SYSCALL_DEFINE2(statfs, const char __user *, pathname, struct statfs __user *, buf)
{
	struct kstatfs st;
	int error = user_statfs(pathname, &st);
	if (!error)
		error = do_statfs_native(&st, buf);
	return error;
}

SYSCALL_DEFINE3(statfs64, const char __user *, pathname, size_t, sz, struct statfs64 __user *, buf)
{
	struct kstatfs st;
	int error;
	if (sz != sizeof(*buf))
		return -EINVAL;
	error = user_statfs(pathname, &st);
	if (!error)
		error = do_statfs64(&st, buf);
	return error;
}

SYSCALL_DEFINE2(fstatfs, unsigned int, fd, struct statfs __user *, buf)
{
	struct kstatfs st;
	int error = fd_statfs(fd, &st);
	if (!error)
		error = do_statfs_native(&st, buf);
	return error;
}

SYSCALL_DEFINE3(fstatfs64, unsigned int, fd, size_t, sz, struct statfs64 __user *, buf)
{
	struct kstatfs st;
	int error;

	if (sz != sizeof(*buf))
		return -EINVAL;

	error = fd_statfs(fd, &st);
	if (!error)
		error = do_statfs64(&st, buf);
	return error;
}

static int vfs_ustat(dev_t dev, struct kstatfs *sbuf)
{
	struct super_block *s = user_get_super(dev, false);
	int err;
	if (!s)
		return -EINVAL;

	err = statfs_by_dentry(s->s_root, sbuf);
	drop_super(s);
	return err;
}

SYSCALL_DEFINE2(ustat, unsigned, dev, struct ustat __user *, ubuf)
{
	struct ustat tmp;
	struct kstatfs sbuf;
	int err = vfs_ustat(new_decode_dev(dev), &sbuf);
	if (err)
		return err;

	memset(&tmp,0,sizeof(struct ustat));
	tmp.f_tfree = sbuf.f_bfree;
	if (IS_ENABLED(CONFIG_ARCH_32BIT_USTAT_F_TINODE))
		tmp.f_tinode = min_t(u64, sbuf.f_ffree, UINT_MAX);
	else
		tmp.f_tinode = sbuf.f_ffree;

	return copy_to_user(ubuf, &tmp, sizeof(struct ustat)) ? -EFAULT : 0;
}

#ifdef CONFIG_COMPAT
static int put_compat_statfs(struct compat_statfs __user *ubuf, struct kstatfs *kbuf)
{
	struct compat_statfs buf;
	if (sizeof ubuf->f_blocks == 4) {
		if ((kbuf->f_blocks | kbuf->f_bfree | kbuf->f_bavail |
		     kbuf->f_bsize | kbuf->f_frsize) & 0xffffffff00000000ULL)
			return -EOVERFLOW;
		/* f_files and f_ffree may be -1; it's okay
		 * to stuff that into 32 bits */
		if (kbuf->f_files != 0xffffffffffffffffULL
		 && (kbuf->f_files & 0xffffffff00000000ULL))
			return -EOVERFLOW;
		if (kbuf->f_ffree != 0xffffffffffffffffULL
		 && (kbuf->f_ffree & 0xffffffff00000000ULL))
			return -EOVERFLOW;
	}
	memset(&buf, 0, sizeof(struct compat_statfs));
	buf.f_type = kbuf->f_type;
	buf.f_bsize = kbuf->f_bsize;
	buf.f_blocks = kbuf->f_blocks;
	buf.f_bfree = kbuf->f_bfree;
	buf.f_bavail = kbuf->f_bavail;
	buf.f_files = kbuf->f_files;
	buf.f_ffree = kbuf->f_ffree;
	buf.f_namelen = kbuf->f_namelen;
	buf.f_fsid.val[0] = kbuf->f_fsid.val[0];
	buf.f_fsid.val[1] = kbuf->f_fsid.val[1];
	buf.f_frsize = kbuf->f_frsize;
	buf.f_flags = kbuf->f_flags;
	if (copy_to_user(ubuf, &buf, sizeof(struct compat_statfs)))
		return -EFAULT;
	return 0;
}

/*
 * The following statfs calls are copies of code from fs/statfs.c and
 * should be checked against those from time to time
 */
COMPAT_SYSCALL_DEFINE2(statfs, const char __user *, pathname, struct compat_statfs __user *, buf)
{
	struct kstatfs tmp;
	int error = user_statfs(pathname, &tmp);
	if (!error)
		error = put_compat_statfs(buf, &tmp);
	return error;
}

COMPAT_SYSCALL_DEFINE2(fstatfs, unsigned int, fd, struct compat_statfs __user *, buf)
{
	struct kstatfs tmp;
	int error = fd_statfs(fd, &tmp);
	if (!error)
		error = put_compat_statfs(buf, &tmp);
	return error;
}

static int put_compat_statfs64(struct compat_statfs64 __user *ubuf, struct kstatfs *kbuf)
{
	struct compat_statfs64 buf;

	if ((kbuf->f_bsize | kbuf->f_frsize) & 0xffffffff00000000ULL)
		return -EOVERFLOW;

	memset(&buf, 0, sizeof(struct compat_statfs64));
	buf.f_type = kbuf->f_type;
	buf.f_bsize = kbuf->f_bsize;
	buf.f_blocks = kbuf->f_blocks;
	buf.f_bfree = kbuf->f_bfree;
	buf.f_bavail = kbuf->f_bavail;
	buf.f_files = kbuf->f_files;
	buf.f_ffree = kbuf->f_ffree;
	buf.f_namelen = kbuf->f_namelen;
	buf.f_fsid.val[0] = kbuf->f_fsid.val[0];
	buf.f_fsid.val[1] = kbuf->f_fsid.val[1];
	buf.f_frsize = kbuf->f_frsize;
	buf.f_flags = kbuf->f_flags;
	if (copy_to_user(ubuf, &buf, sizeof(struct compat_statfs64)))
		return -EFAULT;
	return 0;
}

int kcompat_sys_statfs64(const char __user * pathname, compat_size_t sz, struct compat_statfs64 __user * buf)
{
	struct kstatfs tmp;
	int error;

	if (sz != sizeof(*buf))
		return -EINVAL;

	error = user_statfs(pathname, &tmp);
	if (!error)
		error = put_compat_statfs64(buf, &tmp);
	return error;
}

COMPAT_SYSCALL_DEFINE3(statfs64, const char __user *, pathname, compat_size_t, sz, struct compat_statfs64 __user *, buf)
{
	return kcompat_sys_statfs64(pathname, sz, buf);
}

int kcompat_sys_fstatfs64(unsigned int fd, compat_size_t sz, struct compat_statfs64 __user * buf)
{
	struct kstatfs tmp;
	int error;

	if (sz != sizeof(*buf))
		return -EINVAL;

	error = fd_statfs(fd, &tmp);
	if (!error)
		error = put_compat_statfs64(buf, &tmp);
	return error;
}

COMPAT_SYSCALL_DEFINE3(fstatfs64, unsigned int, fd, compat_size_t, sz, struct compat_statfs64 __user *, buf)
{
	return kcompat_sys_fstatfs64(fd, sz, buf);
}

/*
 * This is a copy of sys_ustat, just dealing with a structure layout.
 * Given how simple this syscall is that apporach is more maintainable
 * than the various conversion hacks.
 */
COMPAT_SYSCALL_DEFINE2(ustat, unsigned, dev, struct compat_ustat __user *, u)
{
	struct compat_ustat tmp;
	struct kstatfs sbuf;
	int err = vfs_ustat(new_decode_dev(dev), &sbuf);
	if (err)
		return err;

	memset(&tmp, 0, sizeof(struct compat_ustat));
	tmp.f_tfree = sbuf.f_bfree;
	tmp.f_tinode = sbuf.f_ffree;
	if (copy_to_user(u, &tmp, sizeof(struct compat_ustat)))
		return -EFAULT;
	return 0;
}
#endif
Commit	Line	Data
b2441318	1	// SPDX-License-Identifier: GPL-2.0
7ed1ee61	2	#include <linux/syscalls.h>
630d9c47	3	#include <linux/export.h>
7ed1ee61 AV	4	#include <linux/fs.h>
7ed1ee61 AV	5	#include <linux/file.h>
365b1818	6	#include <linux/mount.h>
7ed1ee61 AV	7	#include <linux/namei.h>
	8	#include <linux/statfs.h>
	9	#include <linux/security.h>
	10	#include <linux/uaccess.h>
4ada54ee	11	#include <linux/compat.h>
cf31e70d	12	#include "internal.h"
7ed1ee61	13
365b1818 CH	14	static int flags_by_mnt(int mnt_flags)
	15	{
	16	int flags = 0;
	17
	18	if (mnt_flags & MNT_READONLY)
	19	flags \|= ST_RDONLY;
	20	if (mnt_flags & MNT_NOSUID)
	21	flags \|= ST_NOSUID;
	22	if (mnt_flags & MNT_NODEV)
	23	flags \|= ST_NODEV;
	24	if (mnt_flags & MNT_NOEXEC)
	25	flags \|= ST_NOEXEC;
	26	if (mnt_flags & MNT_NOATIME)
	27	flags \|= ST_NOATIME;
	28	if (mnt_flags & MNT_NODIRATIME)
	29	flags \|= ST_NODIRATIME;
	30	if (mnt_flags & MNT_RELATIME)
	31	flags \|= ST_RELATIME;
dab741e0 MN	32	if (mnt_flags & MNT_NOSYMFOLLOW)
dab741e0 MN	33	flags \|= ST_NOSYMFOLLOW;
365b1818 CH	34	return flags;
	35	}
	36
	37	static int flags_by_sb(int s_flags)
	38	{
	39	int flags = 0;
1751e8a6	40	if (s_flags & SB_SYNCHRONOUS)
365b1818	41	flags \|= ST_SYNCHRONOUS;
1751e8a6	42	if (s_flags & SB_MANDLOCK)
365b1818	43	flags \|= ST_MANDLOCK;
1751e8a6	44	if (s_flags & SB_RDONLY)
a8e2b636	45	flags \|= ST_RDONLY;
365b1818 CH	46	return flags;
	47	}
	48
	49	static int calculate_f_flags(struct vfsmount *mnt)
	50	{
	51	return ST_VALID \| flags_by_mnt(mnt->mnt_flags) \|
	52	flags_by_sb(mnt->mnt_sb->s_flags);
	53	}
	54
cf31e70d	55	static int statfs_by_dentry(struct dentry dentry, struct kstatfs buf)
7ed1ee61	56	{
ebabe9a9 CH	57	int retval;
	58
	59	if (!dentry->d_sb->s_op->statfs)
	60	return -ENOSYS;
	61
	62	memset(buf, 0, sizeof(*buf));
	63	retval = security_sb_statfs(dentry);
	64	if (retval)
	65	return retval;
	66	retval = dentry->d_sb->s_op->statfs(dentry, buf);
	67	if (retval == 0 && buf->f_frsize == 0)
	68	buf->f_frsize = buf->f_bsize;
7ed1ee61 AV	69	return retval;
	70	}
	71
ec86ff56 AG	72	int vfs_get_fsid(struct dentry dentry, __kernel_fsid_t fsid)
	73	{
	74	struct kstatfs st;
	75	int error;
	76
	77	error = statfs_by_dentry(dentry, &st);
	78	if (error)
	79	return error;
	80
	81	*fsid = st.f_fsid;
	82	return 0;
	83	}
	84	EXPORT_SYMBOL(vfs_get_fsid);
	85
f0bb5aaf	86	int vfs_statfs(const struct path path, struct kstatfs buf)
ebabe9a9	87	{
365b1818 CH	88	int error;
	89
	90	error = statfs_by_dentry(path->dentry, buf);
	91	if (!error)
	92	buf->f_flags = calculate_f_flags(path->mnt);
	93	return error;
ebabe9a9	94	}
7ed1ee61 AV	95	EXPORT_SYMBOL(vfs_statfs);
7ed1ee61 AV	96
c8b91acc	97	int user_statfs(const char __user pathname, struct kstatfs st)
7ed1ee61	98	{
c8b91acc	99	struct path path;
96948fc6 JL	100	int error;
	101	unsigned int lookup_flags = LOOKUP_FOLLOW\|LOOKUP_AUTOMOUNT;
	102	retry:
	103	error = user_path_at(AT_FDCWD, pathname, lookup_flags, &path);
c8b91acc AV	104	if (!error) {
	105	error = vfs_statfs(&path, st);
	106	path_put(&path);
96948fc6 JL	107	if (retry_estale(error, lookup_flags)) {
	108	lookup_flags \|= LOOKUP_REVAL;
	109	goto retry;
	110	}
c8b91acc AV	111	}
	112	return error;
	113	}
7ed1ee61	114
c8b91acc AV	115	int fd_statfs(int fd, struct kstatfs *st)
c8b91acc AV	116	{
9d05746e	117	struct fd f = fdget_raw(fd);
c8b91acc	118	int error = -EBADF;
2903ff01 AV	119	if (f.file) {
	120	error = vfs_statfs(&f.file->f_path, st);
	121	fdput(f);
c8b91acc AV	122	}
	123	return error;
	124	}
7ed1ee61	125
c8b91acc AV	126	static int do_statfs_native(struct kstatfs st, struct statfs __user p)
	127	{
	128	struct statfs buf;
	129
	130	if (sizeof(buf) == sizeof(*st))
	131	memcpy(&buf, st, sizeof(*st));
7ed1ee61	132	else {
c8b91acc AV	133	if (sizeof buf.f_blocks == 4) {
	134	if ((st->f_blocks \| st->f_bfree \| st->f_bavail \|
	135	st->f_bsize \| st->f_frsize) &
7ed1ee61 AV	136	0xffffffff00000000ULL)
	137	return -EOVERFLOW;
	138	/*
	139	* f_files and f_ffree may be -1; it's okay to stuff
	140	* that into 32 bits
	141	*/
c8b91acc AV	142	if (st->f_files != -1 &&
c8b91acc AV	143	(st->f_files & 0xffffffff00000000ULL))
7ed1ee61	144	return -EOVERFLOW;
c8b91acc AV	145	if (st->f_ffree != -1 &&
c8b91acc AV	146	(st->f_ffree & 0xffffffff00000000ULL))
7ed1ee61 AV	147	return -EOVERFLOW;
	148	}
	149
c8b91acc AV	150	buf.f_type = st->f_type;
	151	buf.f_bsize = st->f_bsize;
	152	buf.f_blocks = st->f_blocks;
	153	buf.f_bfree = st->f_bfree;
	154	buf.f_bavail = st->f_bavail;
	155	buf.f_files = st->f_files;
	156	buf.f_ffree = st->f_ffree;
	157	buf.f_fsid = st->f_fsid;
	158	buf.f_namelen = st->f_namelen;
	159	buf.f_frsize = st->f_frsize;
	160	buf.f_flags = st->f_flags;
	161	memset(buf.f_spare, 0, sizeof(buf.f_spare));
7ed1ee61	162	}
c8b91acc AV	163	if (copy_to_user(p, &buf, sizeof(buf)))
c8b91acc AV	164	return -EFAULT;
7ed1ee61 AV	165	return 0;
	166	}
	167
c8b91acc	168	static int do_statfs64(struct kstatfs st, struct statfs64 __user p)
7ed1ee61	169	{
c8b91acc AV	170	struct statfs64 buf;
	171	if (sizeof(buf) == sizeof(*st))
	172	memcpy(&buf, st, sizeof(*st));
7ed1ee61	173	else {
c8b91acc AV	174	buf.f_type = st->f_type;
	175	buf.f_bsize = st->f_bsize;
	176	buf.f_blocks = st->f_blocks;
	177	buf.f_bfree = st->f_bfree;
	178	buf.f_bavail = st->f_bavail;
	179	buf.f_files = st->f_files;
	180	buf.f_ffree = st->f_ffree;
	181	buf.f_fsid = st->f_fsid;
	182	buf.f_namelen = st->f_namelen;
	183	buf.f_frsize = st->f_frsize;
	184	buf.f_flags = st->f_flags;
	185	memset(buf.f_spare, 0, sizeof(buf.f_spare));
7ed1ee61	186	}
c8b91acc AV	187	if (copy_to_user(p, &buf, sizeof(buf)))
c8b91acc AV	188	return -EFAULT;
7ed1ee61 AV	189	return 0;
	190	}
	191
	192	SYSCALL_DEFINE2(statfs, const char __user , pathname, struct statfs __user , buf)
	193	{
c8b91acc AV	194	struct kstatfs st;
	195	int error = user_statfs(pathname, &st);
	196	if (!error)
	197	error = do_statfs_native(&st, buf);
7ed1ee61 AV	198	return error;
	199	}
	200
	201	SYSCALL_DEFINE3(statfs64, const char __user , pathname, size_t, sz, struct statfs64 __user , buf)
	202	{
c8b91acc AV	203	struct kstatfs st;
c8b91acc AV	204	int error;
7ed1ee61 AV	205	if (sz != sizeof(*buf))
7ed1ee61 AV	206	return -EINVAL;
c8b91acc AV	207	error = user_statfs(pathname, &st);
	208	if (!error)
	209	error = do_statfs64(&st, buf);
7ed1ee61 AV	210	return error;
	211	}
	212
	213	SYSCALL_DEFINE2(fstatfs, unsigned int, fd, struct statfs __user *, buf)
	214	{
c8b91acc AV	215	struct kstatfs st;
	216	int error = fd_statfs(fd, &st);
	217	if (!error)
	218	error = do_statfs_native(&st, buf);
7ed1ee61 AV	219	return error;
	220	}
	221
	222	SYSCALL_DEFINE3(fstatfs64, unsigned int, fd, size_t, sz, struct statfs64 __user *, buf)
	223	{
c8b91acc	224	struct kstatfs st;
7ed1ee61 AV	225	int error;
	226
	227	if (sz != sizeof(*buf))
	228	return -EINVAL;
	229
c8b91acc AV	230	error = fd_statfs(fd, &st);
	231	if (!error)
	232	error = do_statfs64(&st, buf);
7ed1ee61 AV	233	return error;
	234	}
	235
53fd88ab	236	static int vfs_ustat(dev_t dev, struct kstatfs *sbuf)
7ed1ee61	237	{
4e7b5671	238	struct super_block *s = user_get_super(dev, false);
7ed1ee61	239	int err;
7ed1ee61 AV	240	if (!s)
	241	return -EINVAL;
	242
cf31e70d	243	err = statfs_by_dentry(s->s_root, sbuf);
7ed1ee61	244	drop_super(s);
cf31e70d AV	245	return err;
	246	}
	247
	248	SYSCALL_DEFINE2(ustat, unsigned, dev, struct ustat __user *, ubuf)
	249	{
	250	struct ustat tmp;
	251	struct kstatfs sbuf;
	252	int err = vfs_ustat(new_decode_dev(dev), &sbuf);
7ed1ee61 AV	253	if (err)
	254	return err;
	255
	256	memset(&tmp,0,sizeof(struct ustat));
	257	tmp.f_tfree = sbuf.f_bfree;
96c0a6a7 HC	258	if (IS_ENABLED(CONFIG_ARCH_32BIT_USTAT_F_TINODE))
	259	tmp.f_tinode = min_t(u64, sbuf.f_ffree, UINT_MAX);
	260	else
	261	tmp.f_tinode = sbuf.f_ffree;
7ed1ee61 AV	262
	263	return copy_to_user(ubuf, &tmp, sizeof(struct ustat)) ? -EFAULT : 0;
	264	}
4ada54ee AV	265
	266	#ifdef CONFIG_COMPAT
	267	static int put_compat_statfs(struct compat_statfs __user ubuf, struct kstatfs kbuf)
	268	{
ae2a9762	269	struct compat_statfs buf;
4ada54ee AV	270	if (sizeof ubuf->f_blocks == 4) {
	271	if ((kbuf->f_blocks \| kbuf->f_bfree \| kbuf->f_bavail \|
	272	kbuf->f_bsize \| kbuf->f_frsize) & 0xffffffff00000000ULL)
	273	return -EOVERFLOW;
	274	/* f_files and f_ffree may be -1; it's okay
	275	* to stuff that into 32 bits */
	276	if (kbuf->f_files != 0xffffffffffffffffULL
	277	&& (kbuf->f_files & 0xffffffff00000000ULL))
	278	return -EOVERFLOW;
	279	if (kbuf->f_ffree != 0xffffffffffffffffULL
	280	&& (kbuf->f_ffree & 0xffffffff00000000ULL))
	281	return -EOVERFLOW;
	282	}
ae2a9762 AV	283	memset(&buf, 0, sizeof(struct compat_statfs));
	284	buf.f_type = kbuf->f_type;
	285	buf.f_bsize = kbuf->f_bsize;
	286	buf.f_blocks = kbuf->f_blocks;
	287	buf.f_bfree = kbuf->f_bfree;
	288	buf.f_bavail = kbuf->f_bavail;
	289	buf.f_files = kbuf->f_files;
	290	buf.f_ffree = kbuf->f_ffree;
	291	buf.f_namelen = kbuf->f_namelen;
	292	buf.f_fsid.val[0] = kbuf->f_fsid.val[0];
	293	buf.f_fsid.val[1] = kbuf->f_fsid.val[1];
	294	buf.f_frsize = kbuf->f_frsize;
	295	buf.f_flags = kbuf->f_flags;
	296	if (copy_to_user(ubuf, &buf, sizeof(struct compat_statfs)))
4ada54ee AV	297	return -EFAULT;
	298	return 0;
	299	}
	300
	301	/*
	302	* The following statfs calls are copies of code from fs/statfs.c and
	303	* should be checked against those from time to time
	304	*/
	305	COMPAT_SYSCALL_DEFINE2(statfs, const char __user , pathname, struct compat_statfs __user , buf)
	306	{
	307	struct kstatfs tmp;
	308	int error = user_statfs(pathname, &tmp);
	309	if (!error)
	310	error = put_compat_statfs(buf, &tmp);
	311	return error;
	312	}
	313
	314	COMPAT_SYSCALL_DEFINE2(fstatfs, unsigned int, fd, struct compat_statfs __user *, buf)
	315	{
	316	struct kstatfs tmp;
	317	int error = fd_statfs(fd, &tmp);
	318	if (!error)
	319	error = put_compat_statfs(buf, &tmp);
	320	return error;
	321	}
	322
	323	static int put_compat_statfs64(struct compat_statfs64 __user ubuf, struct kstatfs kbuf)
	324	{
ae2a9762	325	struct compat_statfs64 buf;
cc3a7bfe ES	326
	327	if ((kbuf->f_bsize \| kbuf->f_frsize) & 0xffffffff00000000ULL)
	328	return -EOVERFLOW;
	329
ae2a9762 AV	330	memset(&buf, 0, sizeof(struct compat_statfs64));
	331	buf.f_type = kbuf->f_type;
	332	buf.f_bsize = kbuf->f_bsize;
	333	buf.f_blocks = kbuf->f_blocks;
	334	buf.f_bfree = kbuf->f_bfree;
	335	buf.f_bavail = kbuf->f_bavail;
	336	buf.f_files = kbuf->f_files;
	337	buf.f_ffree = kbuf->f_ffree;
	338	buf.f_namelen = kbuf->f_namelen;
	339	buf.f_fsid.val[0] = kbuf->f_fsid.val[0];
	340	buf.f_fsid.val[1] = kbuf->f_fsid.val[1];
	341	buf.f_frsize = kbuf->f_frsize;
	342	buf.f_flags = kbuf->f_flags;
	343	if (copy_to_user(ubuf, &buf, sizeof(struct compat_statfs64)))
4ada54ee AV	344	return -EFAULT;
	345	return 0;
	346	}
	347
9b54bf9d	348	int kcompat_sys_statfs64(const char __user * pathname, compat_size_t sz, struct compat_statfs64 __user * buf)
4ada54ee AV	349	{
	350	struct kstatfs tmp;
	351	int error;
	352
	353	if (sz != sizeof(*buf))
	354	return -EINVAL;
	355
	356	error = user_statfs(pathname, &tmp);
	357	if (!error)
	358	error = put_compat_statfs64(buf, &tmp);
	359	return error;
	360	}
	361
9b54bf9d MR	362	COMPAT_SYSCALL_DEFINE3(statfs64, const char __user , pathname, compat_size_t, sz, struct compat_statfs64 __user , buf)
	363	{
	364	return kcompat_sys_statfs64(pathname, sz, buf);
	365	}
	366
	367	int kcompat_sys_fstatfs64(unsigned int fd, compat_size_t sz, struct compat_statfs64 __user * buf)
4ada54ee AV	368	{
	369	struct kstatfs tmp;
	370	int error;
	371
	372	if (sz != sizeof(*buf))
	373	return -EINVAL;
	374
	375	error = fd_statfs(fd, &tmp);
	376	if (!error)
	377	error = put_compat_statfs64(buf, &tmp);
	378	return error;
	379	}
	380
9b54bf9d MR	381	COMPAT_SYSCALL_DEFINE3(fstatfs64, unsigned int, fd, compat_size_t, sz, struct compat_statfs64 __user *, buf)
	382	{
	383	return kcompat_sys_fstatfs64(fd, sz, buf);
	384	}
	385
4ada54ee AV	386	/*
	387	* This is a copy of sys_ustat, just dealing with a structure layout.
	388	* Given how simple this syscall is that apporach is more maintainable
	389	* than the various conversion hacks.
	390	*/
	391	COMPAT_SYSCALL_DEFINE2(ustat, unsigned, dev, struct compat_ustat __user *, u)
	392	{
	393	struct compat_ustat tmp;
	394	struct kstatfs sbuf;
	395	int err = vfs_ustat(new_decode_dev(dev), &sbuf);
	396	if (err)
	397	return err;
	398
	399	memset(&tmp, 0, sizeof(struct compat_ustat));
	400	tmp.f_tfree = sbuf.f_bfree;
	401	tmp.f_tinode = sbuf.f_ffree;
	402	if (copy_to_user(u, &tmp, sizeof(struct compat_ustat)))
	403	return -EFAULT;
	404	return 0;
	405	}
	406	#endif