diff options
Diffstat (limited to 'fs/utimes.c')
-rw-r--r-- | fs/utimes.c | 137 |
1 files changed, 137 insertions, 0 deletions
diff --git a/fs/utimes.c b/fs/utimes.c new file mode 100644 index 000000000000..1bcd852fc4a9 --- /dev/null +++ b/fs/utimes.c | |||
@@ -0,0 +1,137 @@ | |||
1 | #include <linux/compiler.h> | ||
2 | #include <linux/fs.h> | ||
3 | #include <linux/linkage.h> | ||
4 | #include <linux/namei.h> | ||
5 | #include <linux/utime.h> | ||
6 | #include <asm/uaccess.h> | ||
7 | #include <asm/unistd.h> | ||
8 | |||
9 | #ifdef __ARCH_WANT_SYS_UTIME | ||
10 | |||
11 | /* | ||
12 | * sys_utime() can be implemented in user-level using sys_utimes(). | ||
13 | * Is this for backwards compatibility? If so, why not move it | ||
14 | * into the appropriate arch directory (for those architectures that | ||
15 | * need it). | ||
16 | */ | ||
17 | |||
18 | /* If times==NULL, set access and modification to current time, | ||
19 | * must be owner or have write permission. | ||
20 | * Else, update from *times, must be owner or super user. | ||
21 | */ | ||
22 | asmlinkage long sys_utime(char __user * filename, struct utimbuf __user * times) | ||
23 | { | ||
24 | int error; | ||
25 | struct nameidata nd; | ||
26 | struct inode * inode; | ||
27 | struct iattr newattrs; | ||
28 | |||
29 | error = user_path_walk(filename, &nd); | ||
30 | if (error) | ||
31 | goto out; | ||
32 | inode = nd.dentry->d_inode; | ||
33 | |||
34 | error = -EROFS; | ||
35 | if (IS_RDONLY(inode)) | ||
36 | goto dput_and_out; | ||
37 | |||
38 | /* Don't worry, the checks are done in inode_change_ok() */ | ||
39 | newattrs.ia_valid = ATTR_CTIME | ATTR_MTIME | ATTR_ATIME; | ||
40 | if (times) { | ||
41 | error = -EPERM; | ||
42 | if (IS_APPEND(inode) || IS_IMMUTABLE(inode)) | ||
43 | goto dput_and_out; | ||
44 | |||
45 | error = get_user(newattrs.ia_atime.tv_sec, ×->actime); | ||
46 | newattrs.ia_atime.tv_nsec = 0; | ||
47 | if (!error) | ||
48 | error = get_user(newattrs.ia_mtime.tv_sec, ×->modtime); | ||
49 | newattrs.ia_mtime.tv_nsec = 0; | ||
50 | if (error) | ||
51 | goto dput_and_out; | ||
52 | |||
53 | newattrs.ia_valid |= ATTR_ATIME_SET | ATTR_MTIME_SET; | ||
54 | } else { | ||
55 | error = -EACCES; | ||
56 | if (IS_IMMUTABLE(inode)) | ||
57 | goto dput_and_out; | ||
58 | |||
59 | if (current->fsuid != inode->i_uid && | ||
60 | (error = vfs_permission(&nd, MAY_WRITE)) != 0) | ||
61 | goto dput_and_out; | ||
62 | } | ||
63 | mutex_lock(&inode->i_mutex); | ||
64 | error = notify_change(nd.dentry, &newattrs); | ||
65 | mutex_unlock(&inode->i_mutex); | ||
66 | dput_and_out: | ||
67 | path_release(&nd); | ||
68 | out: | ||
69 | return error; | ||
70 | } | ||
71 | |||
72 | #endif | ||
73 | |||
74 | /* If times==NULL, set access and modification to current time, | ||
75 | * must be owner or have write permission. | ||
76 | * Else, update from *times, must be owner or super user. | ||
77 | */ | ||
78 | long do_utimes(int dfd, char __user *filename, struct timeval *times) | ||
79 | { | ||
80 | int error; | ||
81 | struct nameidata nd; | ||
82 | struct inode * inode; | ||
83 | struct iattr newattrs; | ||
84 | |||
85 | error = __user_walk_fd(dfd, filename, LOOKUP_FOLLOW, &nd); | ||
86 | |||
87 | if (error) | ||
88 | goto out; | ||
89 | inode = nd.dentry->d_inode; | ||
90 | |||
91 | error = -EROFS; | ||
92 | if (IS_RDONLY(inode)) | ||
93 | goto dput_and_out; | ||
94 | |||
95 | /* Don't worry, the checks are done in inode_change_ok() */ | ||
96 | newattrs.ia_valid = ATTR_CTIME | ATTR_MTIME | ATTR_ATIME; | ||
97 | if (times) { | ||
98 | error = -EPERM; | ||
99 | if (IS_APPEND(inode) || IS_IMMUTABLE(inode)) | ||
100 | goto dput_and_out; | ||
101 | |||
102 | newattrs.ia_atime.tv_sec = times[0].tv_sec; | ||
103 | newattrs.ia_atime.tv_nsec = times[0].tv_usec * 1000; | ||
104 | newattrs.ia_mtime.tv_sec = times[1].tv_sec; | ||
105 | newattrs.ia_mtime.tv_nsec = times[1].tv_usec * 1000; | ||
106 | newattrs.ia_valid |= ATTR_ATIME_SET | ATTR_MTIME_SET; | ||
107 | } else { | ||
108 | error = -EACCES; | ||
109 | if (IS_IMMUTABLE(inode)) | ||
110 | goto dput_and_out; | ||
111 | |||
112 | if (current->fsuid != inode->i_uid && | ||
113 | (error = vfs_permission(&nd, MAY_WRITE)) != 0) | ||
114 | goto dput_and_out; | ||
115 | } | ||
116 | mutex_lock(&inode->i_mutex); | ||
117 | error = notify_change(nd.dentry, &newattrs); | ||
118 | mutex_unlock(&inode->i_mutex); | ||
119 | dput_and_out: | ||
120 | path_release(&nd); | ||
121 | out: | ||
122 | return error; | ||
123 | } | ||
124 | |||
125 | asmlinkage long sys_futimesat(int dfd, char __user *filename, struct timeval __user *utimes) | ||
126 | { | ||
127 | struct timeval times[2]; | ||
128 | |||
129 | if (utimes && copy_from_user(×, utimes, sizeof(times))) | ||
130 | return -EFAULT; | ||
131 | return do_utimes(dfd, filename, utimes ? times : NULL); | ||
132 | } | ||
133 | |||
134 | asmlinkage long sys_utimes(char __user *filename, struct timeval __user *utimes) | ||
135 | { | ||
136 | return sys_futimesat(AT_FDCWD, filename, utimes); | ||
137 | } | ||