blob: b3c88952465fa28cce7e0bb213fceaf59873fdf9 [file] [log] [blame]
Alexey Dobriyan82b05472006-09-30 23:27:22 -07001#include <linux/compiler.h>
Ulrich Drepper1c710c82007-05-08 00:33:25 -07002#include <linux/file.h>
Alexey Dobriyan82b05472006-09-30 23:27:22 -07003#include <linux/fs.h>
4#include <linux/linkage.h>
5#include <linux/namei.h>
Al Viro914e2632006-10-18 13:55:46 -04006#include <linux/sched.h>
Ulrich Drepper1c710c82007-05-08 00:33:25 -07007#include <linux/stat.h>
Alexey Dobriyan82b05472006-09-30 23:27:22 -07008#include <linux/utime.h>
9#include <asm/uaccess.h>
10#include <asm/unistd.h>
11
12#ifdef __ARCH_WANT_SYS_UTIME
13
14/*
15 * sys_utime() can be implemented in user-level using sys_utimes().
16 * Is this for backwards compatibility? If so, why not move it
17 * into the appropriate arch directory (for those architectures that
18 * need it).
19 */
20
21/* If times==NULL, set access and modification to current time,
22 * must be owner or have write permission.
23 * Else, update from *times, must be owner or super user.
24 */
Ulrich Drepper1c710c82007-05-08 00:33:25 -070025asmlinkage long sys_utime(char __user *filename, struct utimbuf __user *times)
Alexey Dobriyan82b05472006-09-30 23:27:22 -070026{
Ulrich Drepper1c710c82007-05-08 00:33:25 -070027 struct timespec tv[2];
Alexey Dobriyan82b05472006-09-30 23:27:22 -070028
Alexey Dobriyan82b05472006-09-30 23:27:22 -070029 if (times) {
Ulrich Drepper1c710c82007-05-08 00:33:25 -070030 if (get_user(tv[0].tv_sec, &times->actime) ||
31 get_user(tv[1].tv_sec, &times->modtime))
32 return -EFAULT;
33 tv[0].tv_nsec = 0;
34 tv[1].tv_nsec = 0;
Alexey Dobriyan82b05472006-09-30 23:27:22 -070035 }
Ulrich Drepper1c710c82007-05-08 00:33:25 -070036 return do_utimes(AT_FDCWD, filename, times ? tv : NULL, 0);
Alexey Dobriyan82b05472006-09-30 23:27:22 -070037}
38
39#endif
40
41/* If times==NULL, set access and modification to current time,
42 * must be owner or have write permission.
43 * Else, update from *times, must be owner or super user.
44 */
Ulrich Drepper1c710c82007-05-08 00:33:25 -070045long do_utimes(int dfd, char __user *filename, struct timespec *times, int flags)
Alexey Dobriyan82b05472006-09-30 23:27:22 -070046{
47 int error;
48 struct nameidata nd;
Ulrich Drepper1c710c82007-05-08 00:33:25 -070049 struct dentry *dentry;
50 struct inode *inode;
Alexey Dobriyan82b05472006-09-30 23:27:22 -070051 struct iattr newattrs;
Ulrich Drepper1c710c82007-05-08 00:33:25 -070052 struct file *f = NULL;
Alexey Dobriyan82b05472006-09-30 23:27:22 -070053
Ulrich Drepper1c710c82007-05-08 00:33:25 -070054 error = -EINVAL;
55 if (flags & ~AT_SYMLINK_NOFOLLOW)
Alexey Dobriyan82b05472006-09-30 23:27:22 -070056 goto out;
Ulrich Drepper1c710c82007-05-08 00:33:25 -070057
58 if (filename == NULL && dfd != AT_FDCWD) {
59 error = -EINVAL;
60 if (flags & AT_SYMLINK_NOFOLLOW)
61 goto out;
62
63 error = -EBADF;
64 f = fget(dfd);
65 if (!f)
66 goto out;
67 dentry = f->f_path.dentry;
68 } else {
69 error = __user_walk_fd(dfd, filename, (flags & AT_SYMLINK_NOFOLLOW) ? 0 : LOOKUP_FOLLOW, &nd);
70 if (error)
71 goto out;
72
73 dentry = nd.dentry;
74 }
75
76 inode = dentry->d_inode;
Alexey Dobriyan82b05472006-09-30 23:27:22 -070077
78 error = -EROFS;
79 if (IS_RDONLY(inode))
80 goto dput_and_out;
81
82 /* Don't worry, the checks are done in inode_change_ok() */
83 newattrs.ia_valid = ATTR_CTIME | ATTR_MTIME | ATTR_ATIME;
84 if (times) {
85 error = -EPERM;
86 if (IS_APPEND(inode) || IS_IMMUTABLE(inode))
87 goto dput_and_out;
88
Ulrich Drepper1c710c82007-05-08 00:33:25 -070089 if (times[0].tv_nsec == UTIME_OMIT)
90 newattrs.ia_valid &= ~ATTR_ATIME;
91 else if (times[0].tv_nsec != UTIME_NOW) {
92 newattrs.ia_atime.tv_sec = times[0].tv_sec;
93 newattrs.ia_atime.tv_nsec = times[0].tv_nsec;
94 newattrs.ia_valid |= ATTR_ATIME_SET;
95 }
96
97 if (times[1].tv_nsec == UTIME_OMIT)
98 newattrs.ia_valid &= ~ATTR_MTIME;
99 else if (times[1].tv_nsec != UTIME_NOW) {
100 newattrs.ia_mtime.tv_sec = times[1].tv_sec;
101 newattrs.ia_mtime.tv_nsec = times[1].tv_nsec;
102 newattrs.ia_valid |= ATTR_MTIME_SET;
103 }
Alexey Dobriyan82b05472006-09-30 23:27:22 -0700104 } else {
105 error = -EACCES;
106 if (IS_IMMUTABLE(inode))
107 goto dput_and_out;
108
Linus Torvalds1e5de282007-07-08 12:02:55 -0700109 if (current->fsuid != inode->i_uid) {
110 if (f) {
111 if (!(f->f_mode & FMODE_WRITE))
112 goto dput_and_out;
113 } else {
114 error = vfs_permission(&nd, MAY_WRITE);
115 if (error)
116 goto dput_and_out;
117 }
118 }
Alexey Dobriyan82b05472006-09-30 23:27:22 -0700119 }
120 mutex_lock(&inode->i_mutex);
Ulrich Drepper1c710c82007-05-08 00:33:25 -0700121 error = notify_change(dentry, &newattrs);
Alexey Dobriyan82b05472006-09-30 23:27:22 -0700122 mutex_unlock(&inode->i_mutex);
123dput_and_out:
Ulrich Drepper1c710c82007-05-08 00:33:25 -0700124 if (f)
125 fput(f);
126 else
127 path_release(&nd);
Alexey Dobriyan82b05472006-09-30 23:27:22 -0700128out:
129 return error;
130}
131
Ulrich Drepper1c710c82007-05-08 00:33:25 -0700132asmlinkage long sys_utimensat(int dfd, char __user *filename, struct timespec __user *utimes, int flags)
133{
134 struct timespec tstimes[2];
135
136 if (utimes) {
137 if (copy_from_user(&tstimes, utimes, sizeof(tstimes)))
138 return -EFAULT;
139 if ((tstimes[0].tv_nsec == UTIME_OMIT ||
140 tstimes[0].tv_nsec == UTIME_NOW) &&
141 tstimes[0].tv_sec != 0)
142 return -EINVAL;
143 if ((tstimes[1].tv_nsec == UTIME_OMIT ||
144 tstimes[1].tv_nsec == UTIME_NOW) &&
145 tstimes[1].tv_sec != 0)
146 return -EINVAL;
147
148 /* Nothing to do, we must not even check the path. */
149 if (tstimes[0].tv_nsec == UTIME_OMIT &&
150 tstimes[1].tv_nsec == UTIME_OMIT)
151 return 0;
152 }
153
154 return do_utimes(dfd, filename, utimes ? tstimes : NULL, flags);
155}
156
Alexey Dobriyan82b05472006-09-30 23:27:22 -0700157asmlinkage long sys_futimesat(int dfd, char __user *filename, struct timeval __user *utimes)
158{
159 struct timeval times[2];
Ulrich Drepper1c710c82007-05-08 00:33:25 -0700160 struct timespec tstimes[2];
Alexey Dobriyan82b05472006-09-30 23:27:22 -0700161
Ulrich Drepper1c710c82007-05-08 00:33:25 -0700162 if (utimes) {
163 if (copy_from_user(&times, utimes, sizeof(times)))
164 return -EFAULT;
165
166 /* This test is needed to catch all invalid values. If we
167 would test only in do_utimes we would miss those invalid
168 values truncated by the multiplication with 1000. Note
169 that we also catch UTIME_{NOW,OMIT} here which are only
170 valid for utimensat. */
171 if (times[0].tv_usec >= 1000000 || times[0].tv_usec < 0 ||
172 times[1].tv_usec >= 1000000 || times[1].tv_usec < 0)
173 return -EINVAL;
174
175 tstimes[0].tv_sec = times[0].tv_sec;
176 tstimes[0].tv_nsec = 1000 * times[0].tv_usec;
177 tstimes[1].tv_sec = times[1].tv_sec;
178 tstimes[1].tv_nsec = 1000 * times[1].tv_usec;
179 }
180
181 return do_utimes(dfd, filename, utimes ? tstimes : NULL, 0);
Alexey Dobriyan82b05472006-09-30 23:27:22 -0700182}
183
184asmlinkage long sys_utimes(char __user *filename, struct timeval __user *utimes)
185{
186 return sys_futimesat(AT_FDCWD, filename, utimes);
187}