[thirdparty/linux.git] / fs / utimes.c

// SPDX-License-Identifier: GPL-2.0
#include <linux/file.h>
#include <linux/mount.h>
#include <linux/namei.h>
#include <linux/utime.h>
#include <linux/syscalls.h>
#include <linux/uaccess.h>
#include <linux/compat.h>
#include <asm/unistd.h>
#include <linux/filelock.h>

static bool nsec_valid(long nsec)
{
	if (nsec == UTIME_OMIT || nsec == UTIME_NOW)
		return true;

	return nsec >= 0 && nsec <= 999999999;
}

int vfs_utimes(const struct path *path, struct timespec64 *times)
{
	int error;
	struct iattr newattrs;
	struct inode *inode = path->dentry->d_inode;
	struct inode *delegated_inode = NULL;

	if (times) {
		if (!nsec_valid(times[0].tv_nsec) ||
		    !nsec_valid(times[1].tv_nsec))
			return -EINVAL;
		if (times[0].tv_nsec == UTIME_NOW &&
		    times[1].tv_nsec == UTIME_NOW)
			times = NULL;
	}

	error = mnt_want_write(path->mnt);
	if (error)
		goto out;

	newattrs.ia_valid = ATTR_CTIME | ATTR_MTIME | ATTR_ATIME;
	if (times) {
		if (times[0].tv_nsec == UTIME_OMIT)
			newattrs.ia_valid &= ~ATTR_ATIME;
		else if (times[0].tv_nsec != UTIME_NOW) {
			newattrs.ia_atime = times[0];
			newattrs.ia_valid |= ATTR_ATIME_SET;
		}

		if (times[1].tv_nsec == UTIME_OMIT)
			newattrs.ia_valid &= ~ATTR_MTIME;
		else if (times[1].tv_nsec != UTIME_NOW) {
			newattrs.ia_mtime = times[1];
			newattrs.ia_valid |= ATTR_MTIME_SET;
		}
		/*
		 * Tell setattr_prepare(), that this is an explicit time
		 * update, even if neither ATTR_ATIME_SET nor ATTR_MTIME_SET
		 * were used.
		 */
		newattrs.ia_valid |= ATTR_TIMES_SET;
	} else {
		newattrs.ia_valid |= ATTR_TOUCH;
	}
retry_deleg:
	inode_lock(inode);
	error = notify_change(mnt_idmap(path->mnt), path->dentry, &newattrs,
			      &delegated_inode);
	inode_unlock(inode);
	if (delegated_inode) {
		error = break_deleg_wait(&delegated_inode);
		if (!error)
			goto retry_deleg;
	}

	mnt_drop_write(path->mnt);
out:
	return error;
}

static int do_utimes_path(int dfd, const char __user *filename,
		struct timespec64 *times, int flags)
{
	struct path path;
	int lookup_flags = 0, error;

	if (flags & ~(AT_SYMLINK_NOFOLLOW | AT_EMPTY_PATH))
		return -EINVAL;

	if (!(flags & AT_SYMLINK_NOFOLLOW))
		lookup_flags |= LOOKUP_FOLLOW;
	if (flags & AT_EMPTY_PATH)
		lookup_flags |= LOOKUP_EMPTY;

retry:
	error = user_path_at(dfd, filename, lookup_flags, &path);
	if (error)
		return error;

	error = vfs_utimes(&path, times);
	path_put(&path);
	if (retry_estale(error, lookup_flags)) {
		lookup_flags |= LOOKUP_REVAL;
		goto retry;
	}

	return error;
}

static int do_utimes_fd(int fd, struct timespec64 *times, int flags)
{
	struct fd f;
	int error;

	if (flags)
		return -EINVAL;

	f = fdget(fd);
	if (!f.file)
		return -EBADF;
	error = vfs_utimes(&f.file->f_path, times);
	fdput(f);
	return error;
}

/*
 * do_utimes - change times on filename or file descriptor
 * @dfd: open file descriptor, -1 or AT_FDCWD
 * @filename: path name or NULL
 * @times: new times or NULL
 * @flags: zero or more flags (only AT_SYMLINK_NOFOLLOW for the moment)
 *
 * If filename is NULL and dfd refers to an open file, then operate on
 * the file.  Otherwise look up filename, possibly using dfd as a
 * starting point.
 *
 * If times==NULL, set access and modification to current time,
 * must be owner or have write permission.
 * Else, update from *times, must be owner or super user.
 */
long do_utimes(int dfd, const char __user *filename, struct timespec64 *times,
	       int flags)
{
	if (filename == NULL && dfd != AT_FDCWD)
		return do_utimes_fd(dfd, times, flags);
	return do_utimes_path(dfd, filename, times, flags);
}

SYSCALL_DEFINE4(utimensat, int, dfd, const char __user *, filename,
		struct __kernel_timespec __user *, utimes, int, flags)
{
	struct timespec64 tstimes[2];

	if (utimes) {
		if ((get_timespec64(&tstimes[0], &utimes[0]) ||
			get_timespec64(&tstimes[1], &utimes[1])))
			return -EFAULT;

		/* Nothing to do, we must not even check the path.  */
		if (tstimes[0].tv_nsec == UTIME_OMIT &&
		    tstimes[1].tv_nsec == UTIME_OMIT)
			return 0;
	}

	return do_utimes(dfd, filename, utimes ? tstimes : NULL, flags);
}

#ifdef __ARCH_WANT_SYS_UTIME
/*
 * futimesat(), utimes() and utime() are older versions of utimensat()
 * that are provided for compatibility with traditional C libraries.
 * On modern architectures, we always use libc wrappers around
 * utimensat() instead.
 */
static long do_futimesat(int dfd, const char __user *filename,
			 struct __kernel_old_timeval __user *utimes)
{
	struct __kernel_old_timeval times[2];
	struct timespec64 tstimes[2];

	if (utimes) {
		if (copy_from_user(&times, utimes, sizeof(times)))
			return -EFAULT;

		/* This test is needed to catch all invalid values.  If we
		   would test only in do_utimes we would miss those invalid
		   values truncated by the multiplication with 1000.  Note
		   that we also catch UTIME_{NOW,OMIT} here which are only
		   valid for utimensat.  */
		if (times[0].tv_usec >= 1000000 || times[0].tv_usec < 0 ||
		    times[1].tv_usec >= 1000000 || times[1].tv_usec < 0)
			return -EINVAL;

		tstimes[0].tv_sec = times[0].tv_sec;
		tstimes[0].tv_nsec = 1000 * times[0].tv_usec;
		tstimes[1].tv_sec = times[1].tv_sec;
		tstimes[1].tv_nsec = 1000 * times[1].tv_usec;
	}

	return do_utimes(dfd, filename, utimes ? tstimes : NULL, 0);
}


SYSCALL_DEFINE3(futimesat, int, dfd, const char __user *, filename,
		struct __kernel_old_timeval __user *, utimes)
{
	return do_futimesat(dfd, filename, utimes);
}

SYSCALL_DEFINE2(utimes, char __user *, filename,
		struct __kernel_old_timeval __user *, utimes)
{
	return do_futimesat(AT_FDCWD, filename, utimes);
}

SYSCALL_DEFINE2(utime, char __user *, filename, struct utimbuf __user *, times)
{
	struct timespec64 tv[2];

	if (times) {
		if (get_user(tv[0].tv_sec, &times->actime) ||
		    get_user(tv[1].tv_sec, &times->modtime))
			return -EFAULT;
		tv[0].tv_nsec = 0;
		tv[1].tv_nsec = 0;
	}
	return do_utimes(AT_FDCWD, filename, times ? tv : NULL, 0);
}
#endif

#ifdef CONFIG_COMPAT_32BIT_TIME
/*
 * Not all architectures have sys_utime, so implement this in terms
 * of sys_utimes.
 */
#ifdef __ARCH_WANT_SYS_UTIME32
SYSCALL_DEFINE2(utime32, const char __user *, filename,
		struct old_utimbuf32 __user *, t)
{
	struct timespec64 tv[2];

	if (t) {
		if (get_user(tv[0].tv_sec, &t->actime) ||
		    get_user(tv[1].tv_sec, &t->modtime))
			return -EFAULT;
		tv[0].tv_nsec = 0;
		tv[1].tv_nsec = 0;
	}
	return do_utimes(AT_FDCWD, filename, t ? tv : NULL, 0);
}
#endif

SYSCALL_DEFINE4(utimensat_time32, unsigned int, dfd, const char __user *, filename, struct old_timespec32 __user *, t, int, flags)
{
	struct timespec64 tv[2];

	if  (t) {
		if (get_old_timespec32(&tv[0], &t[0]) ||
		    get_old_timespec32(&tv[1], &t[1]))
			return -EFAULT;

		if (tv[0].tv_nsec == UTIME_OMIT && tv[1].tv_nsec == UTIME_OMIT)
			return 0;
	}
	return do_utimes(dfd, filename, t ? tv : NULL, flags);
}

#ifdef __ARCH_WANT_SYS_UTIME32
static long do_compat_futimesat(unsigned int dfd, const char __user *filename,
				struct old_timeval32 __user *t)
{
	struct timespec64 tv[2];

	if (t) {
		if (get_user(tv[0].tv_sec, &t[0].tv_sec) ||
		    get_user(tv[0].tv_nsec, &t[0].tv_usec) ||
		    get_user(tv[1].tv_sec, &t[1].tv_sec) ||
		    get_user(tv[1].tv_nsec, &t[1].tv_usec))
			return -EFAULT;
		if (tv[0].tv_nsec >= 1000000 || tv[0].tv_nsec < 0 ||
		    tv[1].tv_nsec >= 1000000 || tv[1].tv_nsec < 0)
			return -EINVAL;
		tv[0].tv_nsec *= 1000;
		tv[1].tv_nsec *= 1000;
	}
	return do_utimes(dfd, filename, t ? tv : NULL, 0);
}

SYSCALL_DEFINE3(futimesat_time32, unsigned int, dfd,
		       const char __user *, filename,
		       struct old_timeval32 __user *, t)
{
	return do_compat_futimesat(dfd, filename, t);
}

SYSCALL_DEFINE2(utimes_time32, const char __user *, filename, struct old_timeval32 __user *, t)
{
	return do_compat_futimesat(AT_FDCWD, filename, t);
}
#endif
#endif
Commit	Line	Data
b2441318	1	// SPDX-License-Identifier: GPL-2.0
1c710c89	2	#include <linux/file.h>
74f9fdfa	3	#include <linux/mount.h>
82b0547c AD	4	#include <linux/namei.h>
82b0547c AD	5	#include <linux/utime.h>
12c2ab5e	6	#include <linux/syscalls.h>
7c0f6ba6	7	#include <linux/uaccess.h>
1a060ba3	8	#include <linux/compat.h>
82b0547c	9	#include <asm/unistd.h>
5970e15d	10	#include <linux/filelock.h>
82b0547c	11
043f46f6 MS	12	static bool nsec_valid(long nsec)
043f46f6 MS	13	{
4cca9226	14	if (nsec == UTIME_OMIT \|\| nsec == UTIME_NOW)
043f46f6 MS	15	return true;
	16
	17	return nsec >= 0 && nsec <= 999999999;
	18	}
	19
fd5ad30c	20	int vfs_utimes(const struct path path, struct timespec64 times)
82b0547c AD	21	{
82b0547c AD	22	int error;
82b0547c	23	struct iattr newattrs;
e9b76fed	24	struct inode *inode = path->dentry->d_inode;
27ac0ffe	25	struct inode *delegated_inode = NULL;
82b0547c	26
27eb11c9 CH	27	if (times) {
	28	if (!nsec_valid(times[0].tv_nsec) \|\|
	29	!nsec_valid(times[1].tv_nsec))
	30	return -EINVAL;
	31	if (times[0].tv_nsec == UTIME_NOW &&
	32	times[1].tv_nsec == UTIME_NOW)
	33	times = NULL;
	34	}
	35
e9b76fed	36	error = mnt_want_write(path->mnt);
74f9fdfa	37	if (error)
e9b76fed	38	goto out;
82b0547c	39
82b0547c AD	40	newattrs.ia_valid = ATTR_CTIME \| ATTR_MTIME \| ATTR_ATIME;
82b0547c AD	41	if (times) {
1c710c89 UD	42	if (times[0].tv_nsec == UTIME_OMIT)
	43	newattrs.ia_valid &= ~ATTR_ATIME;
	44	else if (times[0].tv_nsec != UTIME_NOW) {
eb31e2f6	45	newattrs.ia_atime = times[0];
1c710c89 UD	46	newattrs.ia_valid \|= ATTR_ATIME_SET;
	47	}
	48
	49	if (times[1].tv_nsec == UTIME_OMIT)
	50	newattrs.ia_valid &= ~ATTR_MTIME;
	51	else if (times[1].tv_nsec != UTIME_NOW) {
eb31e2f6	52	newattrs.ia_mtime = times[1];
1c710c89 UD	53	newattrs.ia_valid \|= ATTR_MTIME_SET;
1c710c89 UD	54	}
4cca9226	55	/*
31051c85	56	* Tell setattr_prepare(), that this is an explicit time
9767d749 MS	57	* update, even if neither ATTR_ATIME_SET nor ATTR_MTIME_SET
9767d749 MS	58	* were used.
4cca9226	59	*/
9767d749	60	newattrs.ia_valid \|= ATTR_TIMES_SET;
4cca9226	61	} else {
f2b20f6e	62	newattrs.ia_valid \|= ATTR_TOUCH;
82b0547c	63	}
27ac0ffe	64	retry_deleg:
5955102c	65	inode_lock(inode);
abf08576	66	error = notify_change(mnt_idmap(path->mnt), path->dentry, &newattrs,
2f221d6f	67	&delegated_inode);
5955102c	68	inode_unlock(inode);
27ac0ffe BF	69	if (delegated_inode) {
	70	error = break_deleg_wait(&delegated_inode);
	71	if (!error)
	72	goto retry_deleg;
	73	}
e9b76fed	74
e9b76fed MS	75	mnt_drop_write(path->mnt);
	76	out:
	77	return error;
	78	}
	79
9d4b74ae CH	80	static int do_utimes_path(int dfd, const char __user *filename,
	81	struct timespec64 *times, int flags)
	82	{
	83	struct path path;
	84	int lookup_flags = 0, error;
	85
9d4b74ae CH	86	if (flags & ~(AT_SYMLINK_NOFOLLOW \| AT_EMPTY_PATH))
	87	return -EINVAL;
	88
	89	if (!(flags & AT_SYMLINK_NOFOLLOW))
	90	lookup_flags \|= LOOKUP_FOLLOW;
	91	if (flags & AT_EMPTY_PATH)
	92	lookup_flags \|= LOOKUP_EMPTY;
	93
	94	retry:
	95	error = user_path_at(dfd, filename, lookup_flags, &path);
	96	if (error)
	97	return error;
	98
fd5ad30c	99	error = vfs_utimes(&path, times);
9d4b74ae CH	100	path_put(&path);
	101	if (retry_estale(error, lookup_flags)) {
	102	lookup_flags \|= LOOKUP_REVAL;
	103	goto retry;
	104	}
	105
	106	return error;
	107	}
	108
	109	static int do_utimes_fd(int fd, struct timespec64 *times, int flags)
	110	{
	111	struct fd f;
	112	int error;
	113
9d4b74ae CH	114	if (flags)
	115	return -EINVAL;
	116
	117	f = fdget(fd);
	118	if (!f.file)
	119	return -EBADF;
fd5ad30c	120	error = vfs_utimes(&f.file->f_path, times);
9d4b74ae CH	121	fdput(f);
	122	return error;
	123	}
	124
e9b76fed MS	125	/*
	126	* do_utimes - change times on filename or file descriptor
	127	* @dfd: open file descriptor, -1 or AT_FDCWD
	128	* @filename: path name or NULL
	129	* @times: new times or NULL
	130	* @flags: zero or more flags (only AT_SYMLINK_NOFOLLOW for the moment)
	131	*
	132	* If filename is NULL and dfd refers to an open file, then operate on
	133	* the file. Otherwise look up filename, possibly using dfd as a
	134	* starting point.
	135	*
	136	* If times==NULL, set access and modification to current time,
	137	* must be owner or have write permission.
	138	* Else, update from *times, must be owner or super user.
	139	*/
aaed2dd8	140	long do_utimes(int dfd, const char __user filename, struct timespec64 times,
c7887325	141	int flags)
e9b76fed	142	{
9d4b74ae CH	143	if (filename == NULL && dfd != AT_FDCWD)
	144	return do_utimes_fd(dfd, times, flags);
	145	return do_utimes_path(dfd, filename, times, flags);
82b0547c AD	146	}
82b0547c AD	147
c7887325	148	SYSCALL_DEFINE4(utimensat, int, dfd, const char __user *, filename,
a4f7a300	149	struct __kernel_timespec __user *, utimes, int, flags)
1c710c89	150	{
aaed2dd8	151	struct timespec64 tstimes[2];
1c710c89 UD	152
1c710c89 UD	153	if (utimes) {
aaed2dd8 DD	154	if ((get_timespec64(&tstimes[0], &utimes[0]) \|\|
aaed2dd8 DD	155	get_timespec64(&tstimes[1], &utimes[1])))
1c710c89	156	return -EFAULT;
1c710c89 UD	157
	158	/* Nothing to do, we must not even check the path. */
	159	if (tstimes[0].tv_nsec == UTIME_OMIT &&
	160	tstimes[1].tv_nsec == UTIME_OMIT)
	161	return 0;
	162	}
	163
	164	return do_utimes(dfd, filename, utimes ? tstimes : NULL, flags);
	165	}
	166
185cfaf7 AB	167	#ifdef __ARCH_WANT_SYS_UTIME
	168	/*
	169	* futimesat(), utimes() and utime() are older versions of utimensat()
	170	* that are provided for compatibility with traditional C libraries.
	171	* On modern architectures, we always use libc wrappers around
	172	* utimensat() instead.
	173	*/
f1390358	174	static long do_futimesat(int dfd, const char __user *filename,
75d319c0	175	struct __kernel_old_timeval __user *utimes)
82b0547c	176	{
75d319c0	177	struct __kernel_old_timeval times[2];
aaed2dd8	178	struct timespec64 tstimes[2];
1c710c89 UD	179
	180	if (utimes) {
	181	if (copy_from_user(&times, utimes, sizeof(times)))
	182	return -EFAULT;
	183
	184	/* This test is needed to catch all invalid values. If we
	185	would test only in do_utimes we would miss those invalid
	186	values truncated by the multiplication with 1000. Note
	187	that we also catch UTIME_{NOW,OMIT} here which are only
	188	valid for utimensat. */
	189	if (times[0].tv_usec >= 1000000 \|\| times[0].tv_usec < 0 \|\|
	190	times[1].tv_usec >= 1000000 \|\| times[1].tv_usec < 0)
	191	return -EINVAL;
	192
	193	tstimes[0].tv_sec = times[0].tv_sec;
	194	tstimes[0].tv_nsec = 1000 * times[0].tv_usec;
	195	tstimes[1].tv_sec = times[1].tv_sec;
	196	tstimes[1].tv_nsec = 1000 * times[1].tv_usec;
	197	}
82b0547c	198
1c710c89	199	return do_utimes(dfd, filename, utimes ? tstimes : NULL, 0);
82b0547c AD	200	}
82b0547c AD	201
f1390358 DB	202
f1390358 DB	203	SYSCALL_DEFINE3(futimesat, int, dfd, const char __user *, filename,
75d319c0	204	struct __kernel_old_timeval __user *, utimes)
f1390358 DB	205	{
	206	return do_futimesat(dfd, filename, utimes);
	207	}
	208
003d7ab4	209	SYSCALL_DEFINE2(utimes, char __user *, filename,
75d319c0	210	struct __kernel_old_timeval __user *, utimes)
82b0547c	211	{
f1390358	212	return do_futimesat(AT_FDCWD, filename, utimes);
82b0547c	213	}
1a060ba3	214
185cfaf7 AB	215	SYSCALL_DEFINE2(utime, char __user , filename, struct utimbuf __user , times)
	216	{
	217	struct timespec64 tv[2];
	218
	219	if (times) {
	220	if (get_user(tv[0].tv_sec, &times->actime) \|\|
	221	get_user(tv[1].tv_sec, &times->modtime))
	222	return -EFAULT;
	223	tv[0].tv_nsec = 0;
	224	tv[1].tv_nsec = 0;
	225	}
	226	return do_utimes(AT_FDCWD, filename, times ? tv : NULL, 0);
	227	}
	228	#endif
	229
4faea239	230	#ifdef CONFIG_COMPAT_32BIT_TIME
1a060ba3 AV	231	/*
	232	* Not all architectures have sys_utime, so implement this in terms
	233	* of sys_utimes.
	234	*/
4faea239	235	#ifdef __ARCH_WANT_SYS_UTIME32
8dabe724 AB	236	SYSCALL_DEFINE2(utime32, const char __user *, filename,
8dabe724 AB	237	struct old_utimbuf32 __user *, t)
1a060ba3	238	{
aaed2dd8	239	struct timespec64 tv[2];
1a060ba3 AV	240
	241	if (t) {
	242	if (get_user(tv[0].tv_sec, &t->actime) \|\|
	243	get_user(tv[1].tv_sec, &t->modtime))
	244	return -EFAULT;
	245	tv[0].tv_nsec = 0;
	246	tv[1].tv_nsec = 0;
	247	}
	248	return do_utimes(AT_FDCWD, filename, t ? tv : NULL, 0);
	249	}
4faea239	250	#endif
1a060ba3	251
8dabe724	252	SYSCALL_DEFINE4(utimensat_time32, unsigned int, dfd, const char __user , filename, struct old_timespec32 __user , t, int, flags)
1a060ba3	253	{
aaed2dd8	254	struct timespec64 tv[2];
1a060ba3 AV	255
1a060ba3 AV	256	if (t) {
9afc5eee AB	257	if (get_old_timespec32(&tv[0], &t[0]) \|\|
9afc5eee AB	258	get_old_timespec32(&tv[1], &t[1]))
1a060ba3 AV	259	return -EFAULT;
	260
	261	if (tv[0].tv_nsec == UTIME_OMIT && tv[1].tv_nsec == UTIME_OMIT)
	262	return 0;
	263	}
	264	return do_utimes(dfd, filename, t ? tv : NULL, flags);
	265	}
	266
4faea239	267	#ifdef __ARCH_WANT_SYS_UTIME32
ab641afa	268	static long do_compat_futimesat(unsigned int dfd, const char __user *filename,
9afc5eee	269	struct old_timeval32 __user *t)
1a060ba3	270	{
aaed2dd8	271	struct timespec64 tv[2];
1a060ba3 AV	272
	273	if (t) {
	274	if (get_user(tv[0].tv_sec, &t[0].tv_sec) \|\|
	275	get_user(tv[0].tv_nsec, &t[0].tv_usec) \|\|
	276	get_user(tv[1].tv_sec, &t[1].tv_sec) \|\|
	277	get_user(tv[1].tv_nsec, &t[1].tv_usec))
	278	return -EFAULT;
	279	if (tv[0].tv_nsec >= 1000000 \|\| tv[0].tv_nsec < 0 \|\|
	280	tv[1].tv_nsec >= 1000000 \|\| tv[1].tv_nsec < 0)
	281	return -EINVAL;
	282	tv[0].tv_nsec *= 1000;
	283	tv[1].tv_nsec *= 1000;
	284	}
	285	return do_utimes(dfd, filename, t ? tv : NULL, 0);
	286	}
	287
8dabe724	288	SYSCALL_DEFINE3(futimesat_time32, unsigned int, dfd,
ab641afa	289	const char __user *, filename,
9afc5eee	290	struct old_timeval32 __user *, t)
ab641afa DB	291	{
	292	return do_compat_futimesat(dfd, filename, t);
	293	}
	294
8dabe724	295	SYSCALL_DEFINE2(utimes_time32, const char __user , filename, struct old_timeval32 __user , t)
1a060ba3	296	{
ab641afa	297	return do_compat_futimesat(AT_FDCWD, filename, t);
1a060ba3 AV	298	}
1a060ba3 AV	299	#endif
4faea239	300	#endif