From: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
To: Andrew Morton <akpm@linux-foundation.org>
Cc: Hungyu Lin <dennylin0707@gmail.com>,
brauner@kernel.org, linux-fsdevel@vger.kernel.org,
linux-kernel@vger.kernel.org
Subject: Re: [PATCH] fat: fix parent link count when replacing a sibling directory
Date: Thu, 29 Oct 2026 14:57:43 +0900 [thread overview]
Message-ID: <87fqxpdp60.fsf@mail.parknet.co.jp> (raw)
In-Reply-To: <20261028211626.26103-1-dennylin0707@gmail.com>
Hungyu Lin <dennylin0707@gmail.com> writes:
> vfat_rename() and do_msdos_rename() adjust parent link counts only when
> updating the dotdot entry for a move between different parents. Replacing
> an existing empty directory in the same parent also removes a
> subdirectory, but leaves the parent's link count unchanged.
>
> For example, renaming one of two sibling directories over the other
> leaves the parent with four links instead of three. stat and ls report
> the stale count, and find -links 3 does not match the parent.
>
> Drop the parent's link count for this case after the source entry has
> been removed successfully. Leave cross-parent renames, regular files
> and the existing error paths unchanged.
>
> Signed-off-by: Hungyu Lin <dennylin0707@gmail.com>
Looks good. Thanks.
Acked-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
> ---
> fs/fat/namei_msdos.c | 2 ++
> fs/fat/namei_vfat.c | 2 ++
> 2 files changed, 4 insertions(+)
>
> diff --git a/fs/fat/namei_msdos.c b/fs/fat/namei_msdos.c
> index c7500c2859e0..570dd75dd275 100644
> --- a/fs/fat/namei_msdos.c
> +++ b/fs/fat/namei_msdos.c
> @@ -565,6 +565,8 @@ static int do_msdos_rename(struct inode *old_dir, unsigned char *old_name,
> (void)sync_inode_metadata(old_dir, 1);
>
> if (new_inode) {
> + if (is_dir && old_dir == new_dir)
> + drop_nlink(old_dir);
> drop_nlink(new_inode);
> if (is_dir)
> drop_nlink(new_inode);
> diff --git a/fs/fat/namei_vfat.c b/fs/fat/namei_vfat.c
> index ff7652bf0410..d7e2df5bf7e5 100644
> --- a/fs/fat/namei_vfat.c
> +++ b/fs/fat/namei_vfat.c
> @@ -1011,6 +1011,8 @@ static int vfat_rename(struct inode *old_dir, struct dentry *old_dentry,
> vfat_update_dir_metadata(old_dir, &ts);
>
> if (new_inode) {
> + if (is_dir && old_dir == new_dir)
> + drop_nlink(old_dir);
> drop_nlink(new_inode);
> if (is_dir)
> drop_nlink(new_inode);
--
OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
prev parent reply other threads:[~2026-10-29 5:57 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-10-28 21:16 [PATCH] fat: fix parent link count when replacing a sibling directory Hungyu Lin
2026-10-29 5:57 ` OGAWA Hirofumi [this message]
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=87fqxpdp60.fsf@mail.parknet.co.jp \
--to=hirofumi@mail.parknet.co.jp \
--cc=akpm@linux-foundation.org \
--cc=brauner@kernel.org \
--cc=dennylin0707@gmail.com \
--cc=linux-fsdevel@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox