1 #include <linux/compiler.h>
2 #include <linux/file.h>
4 #include <linux/linkage.h>
5 #include <linux/mount.h>
6 #include <linux/namei.h>
7 #include <linux/sched.h>
8 #include <linux/stat.h>
9 #include <linux/utime.h>
10 #include <linux/syscalls.h>
11 #include <asm/uaccess.h>
12 #include <asm/unistd.h>
14 #ifdef __ARCH_WANT_SYS_UTIME
17 * sys_utime() can be implemented in user-level using sys_utimes().
18 * Is this for backwards compatibility? If so, why not move it
19 * into the appropriate arch directory (for those architectures that
23 /* If times==NULL, set access and modification to current time,
24 * must be owner or have write permission.
25 * Else, update from *times, must be owner or super user.
27 asmlinkage
long sys_utime(char __user
*filename
, struct utimbuf __user
*times
)
29 struct timespec tv
[2];
32 if (get_user(tv
[0].tv_sec
, ×
->actime
) ||
33 get_user(tv
[1].tv_sec
, ×
->modtime
))
38 return do_utimes(AT_FDCWD
, filename
, times
? tv
: NULL
, 0);
43 static bool nsec_special(long nsec
)
45 return nsec
== UTIME_OMIT
|| nsec
== UTIME_NOW
;
48 static bool nsec_valid(long nsec
)
50 if (nsec_special(nsec
))
53 return nsec
>= 0 && nsec
<= 999999999;
56 /* If times==NULL, set access and modification to current time,
57 * must be owner or have write permission.
58 * Else, update from *times, must be owner or super user.
60 long do_utimes(int dfd
, char __user
*filename
, struct timespec
*times
, int flags
)
64 struct dentry
*dentry
;
66 struct iattr newattrs
;
67 struct file
*f
= NULL
;
71 if (times
&& (!nsec_valid(times
[0].tv_nsec
) ||
72 !nsec_valid(times
[1].tv_nsec
))) {
76 if (flags
& ~AT_SYMLINK_NOFOLLOW
)
79 if (filename
== NULL
&& dfd
!= AT_FDCWD
) {
81 if (flags
& AT_SYMLINK_NOFOLLOW
)
88 dentry
= f
->f_path
.dentry
;
91 error
= __user_walk_fd(dfd
, filename
, (flags
& AT_SYMLINK_NOFOLLOW
) ? 0 : LOOKUP_FOLLOW
, &nd
);
95 dentry
= nd
.path
.dentry
;
99 inode
= dentry
->d_inode
;
101 error
= mnt_want_write(mnt
);
105 if (times
&& times
[0].tv_nsec
== UTIME_NOW
&&
106 times
[1].tv_nsec
== UTIME_NOW
)
109 /* Don't worry, the checks are done in inode_change_ok() */
110 newattrs
.ia_valid
= ATTR_CTIME
| ATTR_MTIME
| ATTR_ATIME
;
113 if (IS_APPEND(inode
) || IS_IMMUTABLE(inode
))
114 goto mnt_drop_write_and_out
;
116 if (times
[0].tv_nsec
== UTIME_OMIT
)
117 newattrs
.ia_valid
&= ~ATTR_ATIME
;
118 else if (times
[0].tv_nsec
!= UTIME_NOW
) {
119 newattrs
.ia_atime
.tv_sec
= times
[0].tv_sec
;
120 newattrs
.ia_atime
.tv_nsec
= times
[0].tv_nsec
;
121 newattrs
.ia_valid
|= ATTR_ATIME_SET
;
124 if (times
[1].tv_nsec
== UTIME_OMIT
)
125 newattrs
.ia_valid
&= ~ATTR_MTIME
;
126 else if (times
[1].tv_nsec
!= UTIME_NOW
) {
127 newattrs
.ia_mtime
.tv_sec
= times
[1].tv_sec
;
128 newattrs
.ia_mtime
.tv_nsec
= times
[1].tv_nsec
;
129 newattrs
.ia_valid
|= ATTR_MTIME_SET
;
134 * If times is NULL or both times are either UTIME_OMIT or
135 * UTIME_NOW, then need to check permissions, because
136 * inode_change_ok() won't do it.
138 if (!times
|| (nsec_special(times
[0].tv_nsec
) &&
139 nsec_special(times
[1].tv_nsec
))) {
141 if (IS_IMMUTABLE(inode
))
142 goto mnt_drop_write_and_out
;
144 if (!is_owner_or_cap(inode
)) {
146 if (!(f
->f_mode
& FMODE_WRITE
))
147 goto mnt_drop_write_and_out
;
149 error
= vfs_permission(&nd
, MAY_WRITE
);
151 goto mnt_drop_write_and_out
;
155 mutex_lock(&inode
->i_mutex
);
156 error
= notify_change(dentry
, &newattrs
);
157 mutex_unlock(&inode
->i_mutex
);
158 mnt_drop_write_and_out
:
169 asmlinkage
long sys_utimensat(int dfd
, char __user
*filename
, struct timespec __user
*utimes
, int flags
)
171 struct timespec tstimes
[2];
174 if (copy_from_user(&tstimes
, utimes
, sizeof(tstimes
)))
176 if ((tstimes
[0].tv_nsec
== UTIME_OMIT
||
177 tstimes
[0].tv_nsec
== UTIME_NOW
) &&
178 tstimes
[0].tv_sec
!= 0)
180 if ((tstimes
[1].tv_nsec
== UTIME_OMIT
||
181 tstimes
[1].tv_nsec
== UTIME_NOW
) &&
182 tstimes
[1].tv_sec
!= 0)
185 /* Nothing to do, we must not even check the path. */
186 if (tstimes
[0].tv_nsec
== UTIME_OMIT
&&
187 tstimes
[1].tv_nsec
== UTIME_OMIT
)
191 return do_utimes(dfd
, filename
, utimes
? tstimes
: NULL
, flags
);
194 asmlinkage
long sys_futimesat(int dfd
, char __user
*filename
, struct timeval __user
*utimes
)
196 struct timeval times
[2];
197 struct timespec tstimes
[2];
200 if (copy_from_user(×
, utimes
, sizeof(times
)))
203 /* This test is needed to catch all invalid values. If we
204 would test only in do_utimes we would miss those invalid
205 values truncated by the multiplication with 1000. Note
206 that we also catch UTIME_{NOW,OMIT} here which are only
207 valid for utimensat. */
208 if (times
[0].tv_usec
>= 1000000 || times
[0].tv_usec
< 0 ||
209 times
[1].tv_usec
>= 1000000 || times
[1].tv_usec
< 0)
212 tstimes
[0].tv_sec
= times
[0].tv_sec
;
213 tstimes
[0].tv_nsec
= 1000 * times
[0].tv_usec
;
214 tstimes
[1].tv_sec
= times
[1].tv_sec
;
215 tstimes
[1].tv_nsec
= 1000 * times
[1].tv_usec
;
218 return do_utimes(dfd
, filename
, utimes
? tstimes
: NULL
, 0);
221 asmlinkage
long sys_utimes(char __user
*filename
, struct timeval __user
*utimes
)
223 return sys_futimesat(AT_FDCWD
, filename
, utimes
);
This page took 0.051132 seconds and 6 git commands to generate.