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	Thu, 02 Oct 2025 16:36:49 +0000
Date: Thu, 2 Oct 2025 17:36:49 +0100
From: Al Viro <viro@zeniv.linux.org.uk>
To: Jan Kara <jack@suse.cz>
Cc: Christian Brauner <brauner@kernel.org>, linux-fsdevel@vger.kernel.org,
	Deepanshu Kartikey <kartikey406@gmail.com>,
	syzbot+1d79ebe5383fc016cf07@syzkaller.appspotmail.com,
	stable@vger.kernel.org
Subject: Re: [PATCH] vfs: Don't leak disconnected dentries on umount
Message-ID: <20251002163649.GO39973@ZenIV>
References: <20251002155506.10755-2-jack@suse.cz>
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Sender: Al Viro <viro@ftp.linux.org.uk>

On Thu, Oct 02, 2025 at 05:55:07PM +0200, Jan Kara wrote:

> diff --git a/fs/dcache.c b/fs/dcache.c
> index 65cc11939654..3ec21f9cedba 100644
> --- a/fs/dcache.c
> +++ b/fs/dcache.c
> @@ -2557,6 +2557,8 @@ struct dentry *d_alloc_parallel(struct dentry *parent,
>  	spin_lock(&parent->d_lock);
>  	new->d_parent = dget_dlock(parent);
>  	hlist_add_head(&new->d_sib, &parent->d_children);
> +	if (parent->d_flags & DCACHE_DISCONNECTED)
> +		new->d_flags |= DCACHE_DISCONNECTED;
>  	spin_unlock(&parent->d_lock);

Not a good place for that |=, IMO...