utimensat: AT_EMPTY_PATH support

This makes it possible to use utimensat on an O_PATH file (including
symlinks).

It supersedes the nonstandard utimensat(fd, NULL, ...) form.

Cc: linux-api@vger.kernel.org
Cc: linux-man@vger.kernel.org
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
This commit is contained in:
Miklos Szeredi 2020-05-14 16:44:24 +02:00
parent 9470451505
commit 44a3b87444

View File

@ -95,13 +95,13 @@ long do_utimes(int dfd, const char __user *filename, struct timespec64 *times,
goto out;
}
if (flags & ~AT_SYMLINK_NOFOLLOW)
if (flags & ~(AT_SYMLINK_NOFOLLOW | AT_EMPTY_PATH))
goto out;
if (filename == NULL && dfd != AT_FDCWD) {
struct fd f;
if (flags & AT_SYMLINK_NOFOLLOW)
if (flags)
goto out;
f = fdget(dfd);
@ -117,6 +117,8 @@ long do_utimes(int dfd, const char __user *filename, struct timespec64 *times,
if (!(flags & AT_SYMLINK_NOFOLLOW))
lookup_flags |= LOOKUP_FOLLOW;
if (flags & AT_EMPTY_PATH)
lookup_flags |= LOOKUP_EMPTY;
retry:
error = user_path_at(dfd, filename, lookup_flags, &path);
if (error)