#include <linux/file.h>
#include <linux/fs.h>
#include <linux/linkage.h>
+#include <linux/mount.h>
#include <linux/namei.h>
#include <linux/sched.h>
#include <linux/stat.h>
#include <linux/utime.h>
+#include <linux/syscalls.h>
#include <asm/uaccess.h>
#include <asm/unistd.h>
* must be owner or have write permission.
* Else, update from *times, must be owner or super user.
*/
-asmlinkage long sys_utime(char __user *filename, struct utimbuf __user *times)
+SYSCALL_DEFINE2(utime, char __user *, filename, struct utimbuf __user *, times)
{
struct timespec tv[2];
#endif
-/* If times==NULL, set access and modification to current time,
- * must be owner or have write permission.
- * Else, update from *times, must be owner or super user.
- */
-long do_utimes(int dfd, char __user *filename, struct timespec *times, int flags)
+static bool nsec_valid(long nsec)
+{
+ if (nsec == UTIME_OMIT || nsec == UTIME_NOW)
+ return true;
+
+ return nsec >= 0 && nsec <= 999999999;
+}
+
+static int utimes_common(struct path *path, struct timespec *times)
{
int error;
- struct nameidata nd;
- struct dentry *dentry;
- struct inode *inode;
struct iattr newattrs;
- struct file *f = NULL;
+ struct inode *inode = path->dentry->d_inode;
- error = -EINVAL;
- if (flags & ~AT_SYMLINK_NOFOLLOW)
+ error = mnt_want_write(path->mnt);
+ if (error)
goto out;
- if (filename == NULL && dfd != AT_FDCWD) {
- error = -EINVAL;
- if (flags & AT_SYMLINK_NOFOLLOW)
- goto out;
-
- error = -EBADF;
- f = fget(dfd);
- if (!f)
- goto out;
- dentry = f->f_path.dentry;
- } else {
- error = __user_walk_fd(dfd, filename, (flags & AT_SYMLINK_NOFOLLOW) ? 0 : LOOKUP_FOLLOW, &nd);
- if (error)
- goto out;
-
- dentry = nd.dentry;
- }
-
- inode = dentry->d_inode;
+ if (times && times[0].tv_nsec == UTIME_NOW &&
+ times[1].tv_nsec == UTIME_NOW)
+ times = NULL;
- error = -EROFS;
- if (IS_RDONLY(inode))
- goto dput_and_out;
-
- /* Don't worry, the checks are done in inode_change_ok() */
newattrs.ia_valid = ATTR_CTIME | ATTR_MTIME | ATTR_ATIME;
if (times) {
- error = -EPERM;
- if (IS_APPEND(inode) || IS_IMMUTABLE(inode))
- goto dput_and_out;
-
if (times[0].tv_nsec == UTIME_OMIT)
newattrs.ia_valid &= ~ATTR_ATIME;
else if (times[0].tv_nsec != UTIME_NOW) {
newattrs.ia_mtime.tv_nsec = times[1].tv_nsec;
newattrs.ia_valid |= ATTR_MTIME_SET;
}
+ /*
+ * Tell inode_change_ok(), that this is an explicit time
+ * update, even if neither ATTR_ATIME_SET nor ATTR_MTIME_SET
+ * were used.
+ */
+ newattrs.ia_valid |= ATTR_TIMES_SET;
} else {
+ /*
+ * If times is NULL (or both times are UTIME_NOW),
+ * then we need to check permissions, because
+ * inode_change_ok() won't do it.
+ */
error = -EACCES;
if (IS_IMMUTABLE(inode))
- goto dput_and_out;
+ goto mnt_drop_write_and_out;
- if (current->fsuid != inode->i_uid &&
- (error = vfs_permission(&nd, MAY_WRITE)) != 0)
- goto dput_and_out;
+ if (!inode_owner_or_capable(inode)) {
+ error = inode_permission(inode, MAY_WRITE);
+ if (error)
+ goto mnt_drop_write_and_out;
+ }
}
mutex_lock(&inode->i_mutex);
- error = notify_change(dentry, &newattrs);
+ error = notify_change(path->dentry, &newattrs);
mutex_unlock(&inode->i_mutex);
-dput_and_out:
- if (f)
- fput(f);
- else
- path_release(&nd);
+
+mnt_drop_write_and_out:
+ mnt_drop_write(path->mnt);
out:
return error;
}
-asmlinkage long sys_utimensat(int dfd, char __user *filename, struct timespec __user *utimes, int flags)
+/*
+ * do_utimes - change times on filename or file descriptor
+ * @dfd: open file descriptor, -1 or AT_FDCWD
+ * @filename: path name or NULL
+ * @times: new times or NULL
+ * @flags: zero or more flags (only AT_SYMLINK_NOFOLLOW for the moment)
+ *
+ * If filename is NULL and dfd refers to an open file, then operate on
+ * the file. Otherwise look up filename, possibly using dfd as a
+ * starting point.
+ *
+ * If times==NULL, set access and modification to current time,
+ * must be owner or have write permission.
+ * Else, update from *times, must be owner or super user.
+ */
+long do_utimes(int dfd, const char __user *filename, struct timespec *times,
+ int flags)
+{
+ int error = -EINVAL;
+
+ if (times && (!nsec_valid(times[0].tv_nsec) ||
+ !nsec_valid(times[1].tv_nsec))) {
+ goto out;
+ }
+
+ if (flags & ~AT_SYMLINK_NOFOLLOW)
+ goto out;
+
+ if (filename == NULL && dfd != AT_FDCWD) {
+ struct file *file;
+
+ if (flags & AT_SYMLINK_NOFOLLOW)
+ goto out;
+
+ file = fget(dfd);
+ error = -EBADF;
+ if (!file)
+ goto out;
+
+ error = utimes_common(&file->f_path, times);
+ fput(file);
+ } else {
+ struct path path;
+ int lookup_flags = 0;
+
+ if (!(flags & AT_SYMLINK_NOFOLLOW))
+ lookup_flags |= LOOKUP_FOLLOW;
+
+ error = user_path_at(dfd, filename, lookup_flags, &path);
+ if (error)
+ goto out;
+
+ error = utimes_common(&path, times);
+ path_put(&path);
+ }
+
+out:
+ return error;
+}
+
+SYSCALL_DEFINE4(utimensat, int, dfd, const char __user *, filename,
+ struct timespec __user *, utimes, int, flags)
{
struct timespec tstimes[2];
if (utimes) {
if (copy_from_user(&tstimes, utimes, sizeof(tstimes)))
return -EFAULT;
- if ((tstimes[0].tv_nsec == UTIME_OMIT ||
- tstimes[0].tv_nsec == UTIME_NOW) &&
- tstimes[0].tv_sec != 0)
- return -EINVAL;
- if ((tstimes[1].tv_nsec == UTIME_OMIT ||
- tstimes[1].tv_nsec == UTIME_NOW) &&
- tstimes[1].tv_sec != 0)
- return -EINVAL;
/* Nothing to do, we must not even check the path. */
if (tstimes[0].tv_nsec == UTIME_OMIT &&
return do_utimes(dfd, filename, utimes ? tstimes : NULL, flags);
}
-asmlinkage long sys_futimesat(int dfd, char __user *filename, struct timeval __user *utimes)
+SYSCALL_DEFINE3(futimesat, int, dfd, const char __user *, filename,
+ struct timeval __user *, utimes)
{
struct timeval times[2];
struct timespec tstimes[2];
return do_utimes(dfd, filename, utimes ? tstimes : NULL, 0);
}
-asmlinkage long sys_utimes(char __user *filename, struct timeval __user *utimes)
+SYSCALL_DEFINE2(utimes, char __user *, filename,
+ struct timeval __user *, utimes)
{
return sys_futimesat(AT_FDCWD, filename, utimes);
}
Code Review / linux-2.6.git / blobdiff