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From: Jarkko Sakkinen <jarkko@kernel.org>
To: Herbert Xu <herbert@gondor.apana.org.au>
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 <James.Bottomley@hansenpartnership.com>,
	linux-crypto@vger.kernel.org,
	Stefan Berger <stefanb@linux.ibm.com>,
	Jarkko Sakkinen <jarkko@kernel.org>,
	James Bottomley <James.Bottomley@HansenPartnership.com>,
	Mimi Zohar <zohar@linux.ibm.com>,
	David Howells <dhowells@redhat.com>,
	Paul Moore <paul@paul-moore.com>,
	James Morris <jmorris@namei.org>,
	"Serge E. Hallyn" <serge@hallyn.com>,
	linux-security-module@vger.kernel.org,
	linux-kernel@vger.kernel.org
Subject: [PATCH] KEYS: trusted: Change -EINVAL to -E2BIG
Date: Wed, 29 May 2024 18:02:53 +0300
Message-ID: <20240529150253.27630-1-jarkko@kernel.org>
Precedence: bulk
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Report -E2BIG instead of -EINVAL when too large size for the key blob is
requested. By filtering these errors from other invalid data, this will
help distinguish the overflows.

Link: https://lore.kernel.org/keyrings/D1M4GRF0RL2W.3QHTBXZWNW9RW@kernel.org/
Reviewed-by: Stefan Berger <stefanb@linux.ibm.com>
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
---
I don't think this is a fix and neither needs to be backported but makes
sense for upcoming versions. Sending as a separate patch from the TPM2
asymmetric keys series.
 security/keys/trusted-keys/trusted_tpm2.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/security/keys/trusted-keys/trusted_tpm2.c b/security/keys/trusted-keys/trusted_tpm2.c
index 8b7dd73d94c1..06c8fa7b21ae 100644
--- a/security/keys/trusted-keys/trusted_tpm2.c
+++ b/security/keys/trusted-keys/trusted_tpm2.c
@@ -122,7 +122,7 @@ static int tpm2_key_decode(struct trusted_key_payload *payload,
 		return ret;
 
 	if (ctx.priv_len + ctx.pub_len > MAX_BLOB_SIZE)
-		return -EINVAL;
+		return -E2BIG;
 
 	blob = kmalloc(ctx.priv_len + ctx.pub_len + 4, GFP_KERNEL);
 	if (!blob)
-- 
2.45.1