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Date: Wed, 05 Jun 2024 01:33:32 +0300
Message-Id: <D1RL9GZKU6Y3.2HFU56T053FQB@kernel.org>
Cc: <linux-integrity@vger.kernel.org>, <keyrings@vger.kernel.org>,
 <Andreas.Fuchs@infineon.com>, "James Prestwood" <prestwoj@gmail.com>,
 "David Woodhouse" <dwmw2@infradead.org>, "Eric Biggers"
 <ebiggers@kernel.org>, "James Bottomley"
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 <davem@davemloft.net>, "open list" <linux-kernel@vger.kernel.org>, "Mimi
 Zohar" <zohar@linux.ibm.com>, "David Howells" <dhowells@redhat.com>, "Paul
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 Hallyn" <serge@hallyn.com>, "open list:SECURITY SUBSYSTEM"
 <linux-security-module@vger.kernel.org>
Subject: Re: [PATCH v7 3/5] crypto: tpm2_key: Introduce a TPM2 key type
From: "Jarkko Sakkinen" <jarkko@kernel.org>
To: "Stefan Berger" <stefanb@linux.ibm.com>, "Herbert Xu"
 <herbert@gondor.apana.org.au>
References: <20240528210823.28798-1-jarkko@kernel.org>
 <20240528210823.28798-4-jarkko@kernel.org>
 <97dd7485-51bf-4e47-83ab-957710fc2182@linux.ibm.com>
 <D1REOCZ2XHRY.4U47RZ20QET1@kernel.org>
 <6f0e04c2-4602-4407-9af5-f72610021a6a@linux.ibm.com>
In-Reply-To: <6f0e04c2-4602-4407-9af5-f72610021a6a@linux.ibm.com>

On Tue Jun 4, 2024 at 9:41 PM EEST, Stefan Berger wrote:
>
>
> On 6/4/24 13:23, Jarkko Sakkinen wrote:
> > On Fri May 31, 2024 at 3:35 AM EEST, Stefan Berger wrote:
> >>
>
> >>>   =20
> >>> -	rc =3D tpm2_key_decode(payload, options, &blob);
> >>> -	if (rc) {
> >>> -		/* old form */
> >>> +	key =3D tpm2_key_decode(payload->blob, payload->blob_len);
> >>> +	if (IS_ERR(key)) {
> >>> +		/* Get the error code and reset the pointer to the key: */
> >>> +		rc =3D PTR_ERR(key);
> >>> +		key =3D NULL;
> >>> +
> >>> +		if (rc =3D=3D -ENOMEM)
> >>> +			return -ENOMEM;
> >>> +
> >>> +		/* A sanity check, as only -EBADMSG or -ENOMEM are expected: */
> >>> +		if (rc !=3D -EBADMSG)
> >>> +			pr_err("tpm2_key_decode(): spurious error code %d\n", rc);
> >>
> >> tpm2_key_decode seems simple enough that it only returns key, -ENOMEM =
or
> >> EBADMSG.
> >=20
> > So what is your suggestion here?
>
> You can remove the check resuling in pr_err().

OK, I think so too. Just had to (sanity) check.

>
> >=20
> > The reasoning here is that asymmetric keys use -EBADMSG not only as
> > error but also iterator, when probing which can load a specific key.
> >=20

BR, Jarkko