Commit dda53843 authored by David Safford's avatar David Safford Committed by Jarkko Sakkinen
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KEYS: trusted: tpm2: Fix migratable logic 



When creating (sealing) a new trusted key, migratable
trusted keys have the FIXED_TPM and FIXED_PARENT attributes
set, and non-migratable keys don't. This is backwards, and
also causes creation to fail when creating a migratable key
under a migratable parent. (The TPM thinks you are trying to
seal a non-migratable blob under a migratable parent.)

The following simple patch fixes the logic, and has been
tested for all four combinations of migratable and non-migratable
trusted keys and parent storage keys. With this logic, you will
get a proper failure if you try to create a non-migratable
trusted key under a migratable parent storage key, and all other
combinations work correctly.

Cc: stable@vger.kernel.org # v5.13+
Fixes: e5fb5d2c ("security: keys: trusted: Make sealed key properly interoperable")
Signed-off-by: default avatarDavid Safford <david.safford@gmail.com>
Reviewed-by: default avatarAhmad Fatoum <a.fatoum@pengutronix.de>
Reviewed-by: default avatarJarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: default avatarJarkko Sakkinen <jarkko@kernel.org>
parent 9886142c

security/keys/trusted-keys/trusted_tpm2.c

+2 −2
Original line number Diff line number Diff line
@@ -283,8 +283,8 @@ int tpm2_seal_trusted(struct tpm_chip *chip, 
	/* key properties */

	flags = 0;

	flags |= options->policydigest_len ? 0 : TPM2_OA_USER_WITH_AUTH;

	flags |= payload->migratable ? (TPM2_OA_FIXED_TPM |

					TPM2_OA_FIXED_PARENT) : 0;

	flags |= payload->migratable ? 0 : (TPM2_OA_FIXED_TPM |

					    TPM2_OA_FIXED_PARENT);

	tpm_buf_append_u32(&buf, flags);



	/* policy */