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From:   Namjae Jeon <linkinjeon@kernel.org>
Date:   Thu, 9 Jun 2022 21:35:28 +0900
Message-ID: <CAKYAXd-8HsO71kvwkuF0u56i2JigR5sF58s+ufh4rH7vKUDkCA@mail.gmail.com>
Subject: Re: [PATCH] exfat: use updated exfat_chain directly during renaming
To:     Sungjong Seo <sj1557.seo@samsung.com>
Cc:     linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org
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2022-06-08 11:04 GMT+09:00, Sungjong Seo <sj1557.seo@samsung.com>:
> In order for a file to access its own directory entry set,
> exfat_inode_info(ei) has two copied values. One is ei->dir, which is
> a snapshot of exfat_chain of the parent directory, and the other is
> ei->entry, which is the offset of the start of the directory entry set
> in the parent directory.
>
> Since the parent directory can be updated after the snapshot point,
> it should be used only for accessing one's own directory entry set.
>
> However, as of now, during renaming, it could try to traverse or to
> allocate clusters via snapshot values, it does not make sense.
>
> This potential problem has been revealed when exfat_update_parent_info()
> was removed by commit d8dad2588add ("exfat: fix referencing wrong parent
> directory information after renaming"). However, I don't think it's good
> idea to bring exfat_update_parent_info() back.
>
> Instead, let's use the updated exfat_chain of parent directory diectly.
>
> Fixes: d8dad2588add ("exfat: fix referencing wrong parent directory
> information after renaming")
>
> Signed-off-by: Sungjong Seo <sj1557.seo@samsung.com>
Applied, Thanks for your patch!