From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx1.redhat.com ([209.132.183.28]:33780 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727604AbeKHDgq (ORCPT ); Wed, 7 Nov 2018 22:36:46 -0500 Date: Wed, 7 Nov 2018 13:05:15 -0500 From: Vivek Goyal To: Miklos Szeredi Cc: Al Viro , linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] utimensat: AT_EMPTY_PATH support Message-ID: <20181107180515.GA28296@redhat.com> References: <20181107091552.17100-1-mszeredi@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20181107091552.17100-1-mszeredi@redhat.com> Sender: linux-fsdevel-owner@vger.kernel.org List-ID: On Wed, Nov 07, 2018 at 10:15:52AM +0100, Miklos Szeredi wrote: > This makes it possible to use utimensat on an O_PATH file (including > symlinks). > > It supersedes the nonstandard utimensat(fd, NULL, ...) form. > > Signed-off-by: Miklos Szeredi Thanks for fixing this Miklos. It seems to work for me for following use case I have where I want to change time on symlink opened with O_PATH. symfd = open("foo-symlink.txt", O_PATH | O_NOFOLLOW); utimensat(fd, "", NULL, AT_EMPTY_PATH | AT_SYMLINK_NOFOLLOW); Thanks Vivek > --- > fs/utimes.c | 6 ++++-- > 1 file changed, 4 insertions(+), 2 deletions(-) > > diff --git a/fs/utimes.c b/fs/utimes.c > index bdcf2daf39c1..f9c7ebad19d7 100644 > --- a/fs/utimes.c > +++ b/fs/utimes.c > @@ -97,13 +97,13 @@ 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); > @@ -119,6 +119,8 @@ 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) > -- > 2.14.3 >