#include <linux/compiler.h>
+#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];
+
+ if (times) {
+ if (get_user(tv[0].tv_sec, ×->actime) ||
+ get_user(tv[1].tv_sec, ×->modtime))
+ return -EFAULT;
+ tv[0].tv_nsec = 0;
+ tv[1].tv_nsec = 0;
+ }
+ return do_utimes(AT_FDCWD, filename, times ? tv : NULL, 0);
+}
+
+#endif
+
+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 inode * inode;
struct iattr newattrs;
+ struct inode *inode = path->dentry->d_inode;
- error = user_path_walk(filename, &nd);
+ error = mnt_want_write(path->mnt);
if (error)
goto out;
- inode = nd.dentry->d_inode;
- error = -EROFS;
- if (IS_RDONLY(inode))
- goto dput_and_out;
+ if (times && times[0].tv_nsec == UTIME_NOW &&
+ times[1].tv_nsec == UTIME_NOW)
+ times = NULL;
- /* 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;
-
- error = get_user(newattrs.ia_atime.tv_sec, ×->actime);
- newattrs.ia_atime.tv_nsec = 0;
- if (!error)
- error = get_user(newattrs.ia_mtime.tv_sec, ×->modtime);
- newattrs.ia_mtime.tv_nsec = 0;
- if (error)
- goto dput_and_out;
-
- newattrs.ia_valid |= ATTR_ATIME_SET | ATTR_MTIME_SET;
+ if (times[0].tv_nsec == UTIME_OMIT)
+ newattrs.ia_valid &= ~ATTR_ATIME;
+ else if (times[0].tv_nsec != UTIME_NOW) {
+ newattrs.ia_atime.tv_sec = times[0].tv_sec;
+ newattrs.ia_atime.tv_nsec = times[0].tv_nsec;
+ newattrs.ia_valid |= ATTR_ATIME_SET;
+ }
+
+ if (times[1].tv_nsec == UTIME_OMIT)
+ newattrs.ia_valid &= ~ATTR_MTIME;
+ else if (times[1].tv_nsec != UTIME_NOW) {
+ newattrs.ia_mtime.tv_sec = times[1].tv_sec;
+ 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 {
- error = -EACCES;
+ /*
+ * 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 (!is_owner_or_cap(inode)) {
+ error = inode_permission(inode, MAY_WRITE);
+ if (error)
+ goto mnt_drop_write_and_out;
+ }
}
mutex_lock(&inode->i_mutex);
- error = notify_change(nd.dentry, &newattrs);
+ error = notify_change(path->dentry, &newattrs);
mutex_unlock(&inode->i_mutex);
-dput_and_out:
- path_release(&nd);
+
+mnt_drop_write_and_out:
+ mnt_drop_write(path->mnt);
out:
return error;
}
-#endif
-
-/* If times==NULL, set access and modification to current time,
+/*
+ * 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, char __user *filename, struct timeval *times)
+long do_utimes(int dfd, char __user *filename, struct timespec *times, int flags)
{
- int error;
- struct nameidata nd;
- struct inode * inode;
- struct iattr newattrs;
+ int error = -EINVAL;
- error = __user_walk_fd(dfd, filename, LOOKUP_FOLLOW, &nd);
+ if (times && (!nsec_valid(times[0].tv_nsec) ||
+ !nsec_valid(times[1].tv_nsec))) {
+ goto out;
+ }
- if (error)
+ if (flags & ~AT_SYMLINK_NOFOLLOW)
goto out;
- inode = nd.dentry->d_inode;
- error = -EROFS;
- if (IS_RDONLY(inode))
- goto dput_and_out;
+ if (filename == NULL && dfd != AT_FDCWD) {
+ struct file *file;
- /* 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;
-
- newattrs.ia_atime.tv_sec = times[0].tv_sec;
- newattrs.ia_atime.tv_nsec = times[0].tv_usec * 1000;
- newattrs.ia_mtime.tv_sec = times[1].tv_sec;
- newattrs.ia_mtime.tv_nsec = times[1].tv_usec * 1000;
- newattrs.ia_valid |= ATTR_ATIME_SET | ATTR_MTIME_SET;
+ 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 {
- error = -EACCES;
- if (IS_IMMUTABLE(inode))
- goto dput_and_out;
+ 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;
- if (current->fsuid != inode->i_uid &&
- (error = vfs_permission(&nd, MAY_WRITE)) != 0)
- goto dput_and_out;
+ error = utimes_common(&path, times);
+ path_put(&path);
}
- mutex_lock(&inode->i_mutex);
- error = notify_change(nd.dentry, &newattrs);
- mutex_unlock(&inode->i_mutex);
-dput_and_out:
- path_release(&nd);
+
out:
return error;
}
-asmlinkage long sys_futimesat(int dfd, char __user *filename, struct timeval __user *utimes)
+SYSCALL_DEFINE4(utimensat, int, dfd, 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;
+
+ /* Nothing to do, we must not even check the path. */
+ if (tstimes[0].tv_nsec == UTIME_OMIT &&
+ tstimes[1].tv_nsec == UTIME_OMIT)
+ return 0;
+ }
+
+ return do_utimes(dfd, filename, utimes ? tstimes : NULL, flags);
+}
+
+SYSCALL_DEFINE3(futimesat, int, dfd, char __user *, filename,
+ struct timeval __user *, utimes)
{
struct timeval times[2];
+ struct timespec tstimes[2];
+
+ if (utimes) {
+ if (copy_from_user(×, utimes, sizeof(times)))
+ return -EFAULT;
+
+ /* This test is needed to catch all invalid values. If we
+ would test only in do_utimes we would miss those invalid
+ values truncated by the multiplication with 1000. Note
+ that we also catch UTIME_{NOW,OMIT} here which are only
+ valid for utimensat. */
+ if (times[0].tv_usec >= 1000000 || times[0].tv_usec < 0 ||
+ times[1].tv_usec >= 1000000 || times[1].tv_usec < 0)
+ return -EINVAL;
+
+ tstimes[0].tv_sec = times[0].tv_sec;
+ tstimes[0].tv_nsec = 1000 * times[0].tv_usec;
+ tstimes[1].tv_sec = times[1].tv_sec;
+ tstimes[1].tv_nsec = 1000 * times[1].tv_usec;
+ }
- if (utimes && copy_from_user(×, utimes, sizeof(times)))
- return -EFAULT;
- return do_utimes(dfd, filename, utimes ? times : NULL);
+ 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