blob: a2bef77dc9c9878c3f93684acf86548f443d989f [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>
Dave Hansen74f9fdf2008-02-15 14:37:42 -08005#include <linux/mount.h>
Alexey Dobriyan82b05472006-09-30 23:27:22 -07006#include <linux/namei.h>
Al Viro914e2632006-10-18 13:55:46 -04007#include <linux/sched.h>
Ulrich Drepper1c710c82007-05-08 00:33:25 -07008#include <linux/stat.h>
Alexey Dobriyan82b05472006-09-30 23:27:22 -07009#include <linux/utime.h>
Adrian Bunk12c2ab52008-02-06 01:36:47 -080010#include <linux/syscalls.h>
Alexey Dobriyan82b05472006-09-30 23:27:22 -070011#include <asm/uaccess.h>
12#include <asm/unistd.h>
13
14#ifdef __ARCH_WANT_SYS_UTIME
15
16/*
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
20 * need it).
21 */
22
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.
26 */
Ulrich Drepper1c710c82007-05-08 00:33:25 -070027asmlinkage long sys_utime(char __user *filename, struct utimbuf __user *times)
Alexey Dobriyan82b05472006-09-30 23:27:22 -070028{
Ulrich Drepper1c710c82007-05-08 00:33:25 -070029 struct timespec tv[2];
Alexey Dobriyan82b05472006-09-30 23:27:22 -070030
Alexey Dobriyan82b05472006-09-30 23:27:22 -070031 if (times) {
Ulrich Drepper1c710c82007-05-08 00:33:25 -070032 if (get_user(tv[0].tv_sec, &times->actime) ||
33 get_user(tv[1].tv_sec, &times->modtime))
34 return -EFAULT;
35 tv[0].tv_nsec = 0;
36 tv[1].tv_nsec = 0;
Alexey Dobriyan82b05472006-09-30 23:27:22 -070037 }
Ulrich Drepper1c710c82007-05-08 00:33:25 -070038 return do_utimes(AT_FDCWD, filename, times ? tv : NULL, 0);
Alexey Dobriyan82b05472006-09-30 23:27:22 -070039}
40
41#endif
42
Miklos Szeredi043f46f2007-10-16 23:27:07 -070043static bool nsec_valid(long nsec)
44{
45 if (nsec == UTIME_OMIT || nsec == UTIME_NOW)
46 return true;
47
48 return nsec >= 0 && nsec <= 999999999;
49}
50
Alexey Dobriyan82b05472006-09-30 23:27:22 -070051/* If times==NULL, set access and modification to current time,
52 * must be owner or have write permission.
53 * Else, update from *times, must be owner or super user.
54 */
Ulrich Drepper1c710c82007-05-08 00:33:25 -070055long do_utimes(int dfd, char __user *filename, struct timespec *times, int flags)
Alexey Dobriyan82b05472006-09-30 23:27:22 -070056{
57 int error;
58 struct nameidata nd;
Ulrich Drepper1c710c82007-05-08 00:33:25 -070059 struct dentry *dentry;
60 struct inode *inode;
Alexey Dobriyan82b05472006-09-30 23:27:22 -070061 struct iattr newattrs;
Ulrich Drepper1c710c82007-05-08 00:33:25 -070062 struct file *f = NULL;
Dave Hansen74f9fdf2008-02-15 14:37:42 -080063 struct vfsmount *mnt;
Alexey Dobriyan82b05472006-09-30 23:27:22 -070064
Ulrich Drepper1c710c82007-05-08 00:33:25 -070065 error = -EINVAL;
Miklos Szeredi043f46f2007-10-16 23:27:07 -070066 if (times && (!nsec_valid(times[0].tv_nsec) ||
67 !nsec_valid(times[1].tv_nsec))) {
68 goto out;
69 }
70
Ulrich Drepper1c710c82007-05-08 00:33:25 -070071 if (flags & ~AT_SYMLINK_NOFOLLOW)
Alexey Dobriyan82b05472006-09-30 23:27:22 -070072 goto out;
Ulrich Drepper1c710c82007-05-08 00:33:25 -070073
74 if (filename == NULL && dfd != AT_FDCWD) {
75 error = -EINVAL;
76 if (flags & AT_SYMLINK_NOFOLLOW)
77 goto out;
78
79 error = -EBADF;
80 f = fget(dfd);
81 if (!f)
82 goto out;
83 dentry = f->f_path.dentry;
Dave Hansen74f9fdf2008-02-15 14:37:42 -080084 mnt = f->f_path.mnt;
Ulrich Drepper1c710c82007-05-08 00:33:25 -070085 } else {
86 error = __user_walk_fd(dfd, filename, (flags & AT_SYMLINK_NOFOLLOW) ? 0 : LOOKUP_FOLLOW, &nd);
87 if (error)
88 goto out;
89
Jan Blunck4ac91372008-02-14 19:34:32 -080090 dentry = nd.path.dentry;
Dave Hansen74f9fdf2008-02-15 14:37:42 -080091 mnt = nd.path.mnt;
Ulrich Drepper1c710c82007-05-08 00:33:25 -070092 }
93
94 inode = dentry->d_inode;
Alexey Dobriyan82b05472006-09-30 23:27:22 -070095
Dave Hansen74f9fdf2008-02-15 14:37:42 -080096 error = mnt_want_write(mnt);
97 if (error)
Alexey Dobriyan82b05472006-09-30 23:27:22 -070098 goto dput_and_out;
99
100 /* Don't worry, the checks are done in inode_change_ok() */
101 newattrs.ia_valid = ATTR_CTIME | ATTR_MTIME | ATTR_ATIME;
102 if (times) {
103 error = -EPERM;
104 if (IS_APPEND(inode) || IS_IMMUTABLE(inode))
Dave Hansen74f9fdf2008-02-15 14:37:42 -0800105 goto mnt_drop_write_and_out;
Alexey Dobriyan82b05472006-09-30 23:27:22 -0700106
Ulrich Drepper1c710c82007-05-08 00:33:25 -0700107 if (times[0].tv_nsec == UTIME_OMIT)
108 newattrs.ia_valid &= ~ATTR_ATIME;
109 else if (times[0].tv_nsec != UTIME_NOW) {
110 newattrs.ia_atime.tv_sec = times[0].tv_sec;
111 newattrs.ia_atime.tv_nsec = times[0].tv_nsec;
112 newattrs.ia_valid |= ATTR_ATIME_SET;
113 }
114
115 if (times[1].tv_nsec == UTIME_OMIT)
116 newattrs.ia_valid &= ~ATTR_MTIME;
117 else if (times[1].tv_nsec != UTIME_NOW) {
118 newattrs.ia_mtime.tv_sec = times[1].tv_sec;
119 newattrs.ia_mtime.tv_nsec = times[1].tv_nsec;
120 newattrs.ia_valid |= ATTR_MTIME_SET;
121 }
Alexey Dobriyan82b05472006-09-30 23:27:22 -0700122 } else {
123 error = -EACCES;
124 if (IS_IMMUTABLE(inode))
Dave Hansen74f9fdf2008-02-15 14:37:42 -0800125 goto mnt_drop_write_and_out;
Alexey Dobriyan82b05472006-09-30 23:27:22 -0700126
Satyam Sharma3bd858a2007-07-17 15:00:08 +0530127 if (!is_owner_or_cap(inode)) {
Linus Torvalds1e5de282007-07-08 12:02:55 -0700128 if (f) {
129 if (!(f->f_mode & FMODE_WRITE))
Dave Hansen74f9fdf2008-02-15 14:37:42 -0800130 goto mnt_drop_write_and_out;
Linus Torvalds1e5de282007-07-08 12:02:55 -0700131 } else {
132 error = vfs_permission(&nd, MAY_WRITE);
133 if (error)
Dave Hansen74f9fdf2008-02-15 14:37:42 -0800134 goto mnt_drop_write_and_out;
Linus Torvalds1e5de282007-07-08 12:02:55 -0700135 }
136 }
Alexey Dobriyan82b05472006-09-30 23:27:22 -0700137 }
138 mutex_lock(&inode->i_mutex);
Ulrich Drepper1c710c82007-05-08 00:33:25 -0700139 error = notify_change(dentry, &newattrs);
Alexey Dobriyan82b05472006-09-30 23:27:22 -0700140 mutex_unlock(&inode->i_mutex);
Dave Hansen74f9fdf2008-02-15 14:37:42 -0800141mnt_drop_write_and_out:
142 mnt_drop_write(mnt);
Alexey Dobriyan82b05472006-09-30 23:27:22 -0700143dput_and_out:
Ulrich Drepper1c710c82007-05-08 00:33:25 -0700144 if (f)
145 fput(f);
146 else
Jan Blunck1d957f92008-02-14 19:34:35 -0800147 path_put(&nd.path);
Alexey Dobriyan82b05472006-09-30 23:27:22 -0700148out:
149 return error;
150}
151
Ulrich Drepper1c710c82007-05-08 00:33:25 -0700152asmlinkage long sys_utimensat(int dfd, char __user *filename, struct timespec __user *utimes, int flags)
153{
154 struct timespec tstimes[2];
155
156 if (utimes) {
157 if (copy_from_user(&tstimes, utimes, sizeof(tstimes)))
158 return -EFAULT;
159 if ((tstimes[0].tv_nsec == UTIME_OMIT ||
160 tstimes[0].tv_nsec == UTIME_NOW) &&
161 tstimes[0].tv_sec != 0)
162 return -EINVAL;
163 if ((tstimes[1].tv_nsec == UTIME_OMIT ||
164 tstimes[1].tv_nsec == UTIME_NOW) &&
165 tstimes[1].tv_sec != 0)
166 return -EINVAL;
167
168 /* Nothing to do, we must not even check the path. */
169 if (tstimes[0].tv_nsec == UTIME_OMIT &&
170 tstimes[1].tv_nsec == UTIME_OMIT)
171 return 0;
172 }
173
174 return do_utimes(dfd, filename, utimes ? tstimes : NULL, flags);
175}
176
Alexey Dobriyan82b05472006-09-30 23:27:22 -0700177asmlinkage long sys_futimesat(int dfd, char __user *filename, struct timeval __user *utimes)
178{
179 struct timeval times[2];
Ulrich Drepper1c710c82007-05-08 00:33:25 -0700180 struct timespec tstimes[2];
Alexey Dobriyan82b05472006-09-30 23:27:22 -0700181
Ulrich Drepper1c710c82007-05-08 00:33:25 -0700182 if (utimes) {
183 if (copy_from_user(&times, utimes, sizeof(times)))
184 return -EFAULT;
185
186 /* This test is needed to catch all invalid values. If we
187 would test only in do_utimes we would miss those invalid
188 values truncated by the multiplication with 1000. Note
189 that we also catch UTIME_{NOW,OMIT} here which are only
190 valid for utimensat. */
191 if (times[0].tv_usec >= 1000000 || times[0].tv_usec < 0 ||
192 times[1].tv_usec >= 1000000 || times[1].tv_usec < 0)
193 return -EINVAL;
194
195 tstimes[0].tv_sec = times[0].tv_sec;
196 tstimes[0].tv_nsec = 1000 * times[0].tv_usec;
197 tstimes[1].tv_sec = times[1].tv_sec;
198 tstimes[1].tv_nsec = 1000 * times[1].tv_usec;
199 }
200
201 return do_utimes(dfd, filename, utimes ? tstimes : NULL, 0);
Alexey Dobriyan82b05472006-09-30 23:27:22 -0700202}
203
204asmlinkage long sys_utimes(char __user *filename, struct timeval __user *utimes)
205{
206 return sys_futimesat(AT_FDCWD, filename, utimes);
207}