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	Fri, 14 Feb 2025 03:28:20 +0000
Date: Fri, 14 Feb 2025 03:28:20 +0000
From: Al Viro <viro@zeniv.linux.org.uk>
To: =?iso-8859-1?Q?Lu=EDs?= Henriques <lhenriques@suse.de>
Cc: ceph-devel@vger.kernel.org, linux-fsdevel@vger.kernel.org,
	Ilya Dryomov <idryomov@gmail.com>
Subject: Re: [RFC] odd check in ceph_encode_encrypted_dname()
Message-ID: <20250214032820.GZ1977892@ZenIV>
References: <20250214024756.GY1977892@ZenIV>
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Sender: Al Viro <viro@ftp.linux.org.uk>

On Fri, Feb 14, 2025 at 02:47:56AM +0000, Al Viro wrote:

[snip]

> Am I missing something subtle here?  Can elen be non-positive at that point?

Another fun question: for dentries with name of form _<something>_<inumber>
we end up looking at fscrypt_has_encryption_key() not for the parent,
but for inode with inumber encoded in dentry name.  Fair enough, but...
what happens if we run into such dentry in ceph_mdsc_build_path()?

There the call of ceph_encode_encrypted_fname() is under
	if (fscrypt_has_encryption_key(d_inode(parent)))

Do we need the keys for both?