write in 30M

hc

2024-02-20 ea08eeccae9297f7aabd2ef7f0c2517ac4549acc

 kernel/fs/utimes.c
..
..
@@ -8,35 +8,6 @@
8
8
 #include <linux/compat.h>
9
9
 #include <asm/unistd.h>
10
10
 
11
-#ifdef __ARCH_WANT_SYS_UTIME
12
-
13
-/*
14
- * sys_utime() can be implemented in user-level using sys_utimes().
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- * Is this for backwards compatibility?  If so, why not move it
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- * into the appropriate arch directory (for those architectures that
17
- * need it).
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- */
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-
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-/* If times==NULL, set access and modification to current time,
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- * must be owner or have write permission.
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- * Else, update from *times, must be owner or super user.
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- */
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-SYSCALL_DEFINE2(utime, char __user *, filename, struct utimbuf __user *, times)
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-{
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-	struct timespec64 tv[2];
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-
28
-	if (times) {
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-		if (get_user(tv[0].tv_sec, &times->actime) ||
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-		    get_user(tv[1].tv_sec, &times->modtime))
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-			return -EFAULT;
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-		tv[0].tv_nsec = 0;
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-		tv[1].tv_nsec = 0;
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-	}
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-	return do_utimes(AT_FDCWD, filename, times ? tv : NULL, 0);
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-}
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-
38
-#endif
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-
40
11
 static bool nsec_valid(long nsec)
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12
 {
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13
 	if (nsec == UTIME_OMIT || nsec == UTIME_NOW)
..
..
@@ -45,36 +16,39 @@
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16
 	return nsec >= 0 && nsec <= 999999999;
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17
 }
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18
 
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-static int utimes_common(const struct path *path, struct timespec64 *times)
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+int vfs_utimes(const struct path *path, struct timespec64 *times)
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20
 {
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21
 	int error;
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22
 	struct iattr newattrs;
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23
 	struct inode *inode = path->dentry->d_inode;
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24
 	struct inode *delegated_inode = NULL;
54
25
 
26
+	if (times) {
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+		if (!nsec_valid(times[0].tv_nsec) ||
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+		    !nsec_valid(times[1].tv_nsec))
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+			return -EINVAL;
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+		if (times[0].tv_nsec == UTIME_NOW &&
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+		    times[1].tv_nsec == UTIME_NOW)
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+			times = NULL;
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+	}
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+
55
35
 	error = mnt_want_write(path->mnt);
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36
 	if (error)
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37
 		goto out;
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-
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-	if (times && times[0].tv_nsec == UTIME_NOW &&
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-		     times[1].tv_nsec == UTIME_NOW)
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-		times = NULL;
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38
 
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 	newattrs.ia_valid = ATTR_CTIME | ATTR_MTIME | ATTR_ATIME;
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40
 	if (times) {
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41
 		if (times[0].tv_nsec == UTIME_OMIT)
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42
 			newattrs.ia_valid &= ~ATTR_ATIME;
67
43
 		else if (times[0].tv_nsec != UTIME_NOW) {
68
-			newattrs.ia_atime.tv_sec = times[0].tv_sec;
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-			newattrs.ia_atime.tv_nsec = times[0].tv_nsec;
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+			newattrs.ia_atime = times[0];
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45
 			newattrs.ia_valid |= ATTR_ATIME_SET;
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46
 		}
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47
 
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48
 		if (times[1].tv_nsec == UTIME_OMIT)
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49
 			newattrs.ia_valid &= ~ATTR_MTIME;
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50
 		else if (times[1].tv_nsec != UTIME_NOW) {
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-			newattrs.ia_mtime.tv_sec = times[1].tv_sec;
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-			newattrs.ia_mtime.tv_nsec = times[1].tv_nsec;
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+			newattrs.ia_mtime = times[1];
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52
 			newattrs.ia_valid |= ATTR_MTIME_SET;
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53
 		}
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54
 		/*
..
..
@@ -88,7 +62,7 @@
88
62
 	}
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63
 retry_deleg:
90
64
 	inode_lock(inode);
91
-	error = notify_change2(path->mnt, path->dentry, &newattrs, &delegated_inode);
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+	error = notify_change(path->dentry, &newattrs, &delegated_inode);
92
66
 	inode_unlock(inode);
93
67
 	if (delegated_inode) {
94
68
 		error = break_deleg_wait(&delegated_inode);
..
..
@@ -98,6 +72,51 @@
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72
 
99
73
 	mnt_drop_write(path->mnt);
100
74
 out:
75
+	return error;
76
+}
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+
78
+static int do_utimes_path(int dfd, const char __user *filename,
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+		struct timespec64 *times, int flags)
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+{
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+	struct path path;
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+	int lookup_flags = 0, error;
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+
84
+	if (flags & ~(AT_SYMLINK_NOFOLLOW | AT_EMPTY_PATH))
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+		return -EINVAL;
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+
87
+	if (!(flags & AT_SYMLINK_NOFOLLOW))
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+		lookup_flags |= LOOKUP_FOLLOW;
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+	if (flags & AT_EMPTY_PATH)
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+		lookup_flags |= LOOKUP_EMPTY;
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+
92
+retry:
93
+	error = user_path_at(dfd, filename, lookup_flags, &path);
94
+	if (error)
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+		return error;
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+
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+	error = vfs_utimes(&path, times);
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+	path_put(&path);
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+	if (retry_estale(error, lookup_flags)) {
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+		lookup_flags |= LOOKUP_REVAL;
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+		goto retry;
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+	}
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+
104
+	return error;
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+}
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+
107
+static int do_utimes_fd(int fd, struct timespec64 *times, int flags)
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+{
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+	struct fd f;
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+	int error;
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+
112
+	if (flags)
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+		return -EINVAL;
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+
115
+	f = fdget(fd);
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+	if (!f.file)
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+		return -EBADF;
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+	error = vfs_utimes(&f.file->f_path, times);
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+	fdput(f);
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120
 	return error;
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121
 }
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122
 
..
..
@@ -119,54 +138,13 @@
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138
 long do_utimes(int dfd, const char __user *filename, struct timespec64 *times,
120
139
 	       int flags)
121
140
 {
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-	int error = -EINVAL;
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-
124
-	if (times && (!nsec_valid(times[0].tv_nsec) ||
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-		      !nsec_valid(times[1].tv_nsec))) {
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-		goto out;
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-	}
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-
129
-	if (flags & ~AT_SYMLINK_NOFOLLOW)
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-		goto out;
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-
132
-	if (filename == NULL && dfd != AT_FDCWD) {
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-		struct fd f;
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-
135
-		if (flags & AT_SYMLINK_NOFOLLOW)
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-			goto out;
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-
138
-		f = fdget(dfd);
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-		error = -EBADF;
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-		if (!f.file)
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-			goto out;
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-
143
-		error = utimes_common(&f.file->f_path, times);
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-		fdput(f);
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-	} else {
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-		struct path path;
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-		int lookup_flags = 0;
148
-
149
-		if (!(flags & AT_SYMLINK_NOFOLLOW))
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-			lookup_flags |= LOOKUP_FOLLOW;
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-retry:
152
-		error = user_path_at(dfd, filename, lookup_flags, &path);
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-		if (error)
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-			goto out;
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-
156
-		error = utimes_common(&path, times);
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-		path_put(&path);
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-		if (retry_estale(error, lookup_flags)) {
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-			lookup_flags |= LOOKUP_REVAL;
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-			goto retry;
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-		}
162
-	}
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-
164
-out:
165
-	return error;
141
+	if (filename == NULL && dfd != AT_FDCWD)
142
+		return do_utimes_fd(dfd, times, flags);
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+	return do_utimes_path(dfd, filename, times, flags);
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144
 }
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145
 
168
146
 SYSCALL_DEFINE4(utimensat, int, dfd, const char __user *, filename,
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-		struct timespec __user *, utimes, int, flags)
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+		struct __kernel_timespec __user *, utimes, int, flags)
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148
 {
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149
 	struct timespec64 tstimes[2];
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150
 
..
..
@@ -184,10 +162,17 @@
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162
 	return do_utimes(dfd, filename, utimes ? tstimes : NULL, flags);
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163
 }
186
164
 
165
+#ifdef __ARCH_WANT_SYS_UTIME
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+/*
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+ * futimesat(), utimes() and utime() are older versions of utimensat()
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+ * that are provided for compatibility with traditional C libraries.
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+ * On modern architectures, we always use libc wrappers around
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+ * utimensat() instead.
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+ */
187
172
 static long do_futimesat(int dfd, const char __user *filename,
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-			 struct timeval __user *utimes)
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+			 struct __kernel_old_timeval __user *utimes)
189
174
 {
190
-	struct timeval times[2];
175
+	struct __kernel_old_timeval times[2];
191
176
 	struct timespec64 tstimes[2];
192
177
 
193
178
 	if (utimes) {
..
..
@@ -214,24 +199,40 @@
214
199
 
215
200
 
216
201
 SYSCALL_DEFINE3(futimesat, int, dfd, const char __user *, filename,
217
-		struct timeval __user *, utimes)
202
+		struct __kernel_old_timeval __user *, utimes)
218
203
 {
219
204
 	return do_futimesat(dfd, filename, utimes);
220
205
 }
221
206
 
222
207
 SYSCALL_DEFINE2(utimes, char __user *, filename,
223
-		struct timeval __user *, utimes)
208
+		struct __kernel_old_timeval __user *, utimes)
224
209
 {
225
210
 	return do_futimesat(AT_FDCWD, filename, utimes);
226
211
 }
227
212
 
228
-#ifdef CONFIG_COMPAT
213
+SYSCALL_DEFINE2(utime, char __user *, filename, struct utimbuf __user *, times)
214
+{
215
+	struct timespec64 tv[2];
216
+
217
+	if (times) {
218
+		if (get_user(tv[0].tv_sec, &times->actime) ||
219
+		    get_user(tv[1].tv_sec, &times->modtime))
220
+			return -EFAULT;
221
+		tv[0].tv_nsec = 0;
222
+		tv[1].tv_nsec = 0;
223
+	}
224
+	return do_utimes(AT_FDCWD, filename, times ? tv : NULL, 0);
225
+}
226
+#endif
227
+
228
+#ifdef CONFIG_COMPAT_32BIT_TIME
229
229
 /*
230
230
  * Not all architectures have sys_utime, so implement this in terms
231
231
  * of sys_utimes.
232
232
  */
233
-COMPAT_SYSCALL_DEFINE2(utime, const char __user *, filename,
234
-		       struct compat_utimbuf __user *, t)
233
+#ifdef __ARCH_WANT_SYS_UTIME32
234
+SYSCALL_DEFINE2(utime32, const char __user *, filename,
235
+		struct old_utimbuf32 __user *, t)
235
236
 {
236
237
 	struct timespec64 tv[2];
237
238
 
..
..
@@ -244,14 +245,15 @@
244
245
 	}
245
246
 	return do_utimes(AT_FDCWD, filename, t ? tv : NULL, 0);
246
247
 }
248
+#endif
247
249
 
248
-COMPAT_SYSCALL_DEFINE4(utimensat, unsigned int, dfd, const char __user *, filename, struct compat_timespec __user *, t, int, flags)
250
+SYSCALL_DEFINE4(utimensat_time32, unsigned int, dfd, const char __user *, filename, struct old_timespec32 __user *, t, int, flags)
249
251
 {
250
252
 	struct timespec64 tv[2];
251
253
 
252
254
 	if  (t) {
253
-		if (compat_get_timespec64(&tv[0], &t[0]) ||
254
-		    compat_get_timespec64(&tv[1], &t[1]))
255
+		if (get_old_timespec32(&tv[0], &t[0]) ||
256
+		    get_old_timespec32(&tv[1], &t[1]))
255
257
 			return -EFAULT;
256
258
 
257
259
 		if (tv[0].tv_nsec == UTIME_OMIT && tv[1].tv_nsec == UTIME_OMIT)
..
..
@@ -260,8 +262,9 @@
260
262
 	return do_utimes(dfd, filename, t ? tv : NULL, flags);
261
263
 }
262
264
 
265
+#ifdef __ARCH_WANT_SYS_UTIME32
263
266
 static long do_compat_futimesat(unsigned int dfd, const char __user *filename,
264
-				struct compat_timeval __user *t)
267
+				struct old_timeval32 __user *t)
265
268
 {
266
269
 	struct timespec64 tv[2];
267
270
 
..
..
@@ -280,15 +283,16 @@
280
283
 	return do_utimes(dfd, filename, t ? tv : NULL, 0);
281
284
 }
282
285
 
283
-COMPAT_SYSCALL_DEFINE3(futimesat, unsigned int, dfd,
286
+SYSCALL_DEFINE3(futimesat_time32, unsigned int, dfd,
284
287
 		       const char __user *, filename,
285
-		       struct compat_timeval __user *, t)
288
+		       struct old_timeval32 __user *, t)
286
289
 {
287
290
 	return do_compat_futimesat(dfd, filename, t);
288
291
 }
289
292
 
290
-COMPAT_SYSCALL_DEFINE2(utimes, const char __user *, filename, struct compat_timeval __user *, t)
293
+SYSCALL_DEFINE2(utimes_time32, const char __user *, filename, struct old_timeval32 __user *, t)
291
294
 {
292
295
 	return do_compat_futimesat(AT_FDCWD, filename, t);
293
296
 }
294
297
 #endif
298
+#endif