From patchwork Mon Apr 7 07:17:31 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jarkko Sakkinen X-Patchwork-Id: 14039832 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 3971E176AA1; Mon, 7 Apr 2025 07:17:37 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1744010258; cv=none; b=FuVaGH1PBnTgpWjGhnRqtz6Ew4F0GNYo/1oa7GvNoluIXFyEqpiKOnVzbrJ4lMCM8gI6CTnYOBKliYqaotUB//nzO85j4a5PPY/vBFP35CZ3fNhLufMh7fvzlYtVIw9qihE7P3+J4j4GvfQc+bxu1rg6V8bCZidFdyV6FOO997Y= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1744010258; c=relaxed/simple; bh=ZMpjbqNV5VmvNx/yWcRwPHpaDgDVafqCD1Ypnp/Awhw=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=ZxjVAx1X9FIDRz2NZdYVi+gpjIpK2+ytrgmybAMaf/fakEY57Gi1iATacbqbE3jHZI0yLiMEJ8S6aojs5AO1f3VWQoL8Eu+RGDKJTr0DktZeXBys27L/3/f9b8ovGivzYpFgsQLE0pAsUQK/7T+Cx3p5nw/MQ6TCD8OlksVJLE8= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=INMZ82CW; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="INMZ82CW" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 12981C4CEE8; Mon, 7 Apr 2025 07:17:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1744010257; bh=ZMpjbqNV5VmvNx/yWcRwPHpaDgDVafqCD1Ypnp/Awhw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=INMZ82CWGDwx835l7YQF1L/d1lSwQBKmNVJMiEdhnwGTPIEvwEJIGLd7hxvJ9DFnb nFshLFU8bbnHriaqJ3GBHX8DjYWADh9mRpLCMIpW8tyrAUVIH4IRRYdmZVDw6vIfmb mpdi4x4KEKLhfmOuPBwkoeTSdP73g7PUH8JRewv+lX0XfpcbydJk2C4Ct5NldMAgVN RqhkCO8cBt3qkL75WU5KpkesF4qqnvXnyriLhtdYCoD6qCM1KkwD3Rfdt6XHu3J/5q /E81o25eRmwOFnvq6ZqZySXCmG2CvBk2E2NLvLZ4SaeBYS9EitOfrMkvyNOFdHCsKh evd0G4BIVyqqA== From: Jarkko Sakkinen To: keyrings@vger.kernel.org Cc: Jarkko Sakkinen , stable@vger.kernel.org, Herbert Xu , David Howells , Lukas Wunner , Ignat Korchagin , "David S. Miller" , Peter Huewe , Jason Gunthorpe , Ard Biesheuvel , James Bottomley , linux-crypto@vger.kernel.org, linux-kernel@vger.kernel.org, linux-integrity@vger.kernel.org Subject: [PATCH v2] tpm: Mask TPM RC in tpm2_start_auth_session() Date: Mon, 7 Apr 2025 10:17:31 +0300 Message-Id: <20250407071731.78915-1-jarkko@kernel.org> X-Mailer: git-send-email 2.39.5 In-Reply-To: <20250407062642.72556-1-jarkko@kernel.org> References: <20250407062642.72556-1-jarkko@kernel.org> Precedence: bulk X-Mailing-List: linux-integrity@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 tpm2_start_auth_session() does not mask TPM RC correctly from the callers: [ 28.766528] tpm tpm0: A TPM error (2307) occurred start auth session Process TPM RCs inside tpm2_start_auth_session(), and map them to POSIX error codes. Cc: stable@vger.kernel.org # v6.10+ Fixes: 699e3efd6c64 ("tpm: Add HMAC session start and end functions") Reported-by: Herbert Xu Closes: https://lore.kernel.org/linux-integrity/Z_NgdRHuTKP6JK--@gondor.apana.org.au/ Signed-off-by: Jarkko Sakkinen --- v2: - Investigate TPM rc only after destroying tpm_buf. --- drivers/char/tpm/tpm2-sessions.c | 29 +++++++++++++++-------------- include/linux/tpm.h | 1 + 2 files changed, 16 insertions(+), 14 deletions(-) diff --git a/drivers/char/tpm/tpm2-sessions.c b/drivers/char/tpm/tpm2-sessions.c index 3f89635ba5e8..da382b86dc41 100644 --- a/drivers/char/tpm/tpm2-sessions.c +++ b/drivers/char/tpm/tpm2-sessions.c @@ -40,11 +40,6 @@ * * These are the usage functions: * - * tpm2_start_auth_session() which allocates the opaque auth structure - * and gets a session from the TPM. This must be called before - * any of the following functions. The session is protected by a - * session_key which is derived from a random salt value - * encrypted to the NULL seed. * tpm2_end_auth_session() kills the session and frees the resources. * Under normal operation this function is done by * tpm_buf_check_hmac_response(), so this is only to be used on @@ -963,16 +958,13 @@ static int tpm2_load_null(struct tpm_chip *chip, u32 *null_key) } /** - * tpm2_start_auth_session() - create a HMAC authentication session with the TPM - * @chip: the TPM chip structure to create the session with + * tpm2_start_auth_session() - Create an a HMAC authentication session + * @chip: A TPM chip * - * This function loads the NULL seed from its saved context and starts - * an authentication session on the null seed, fills in the - * @chip->auth structure to contain all the session details necessary - * for performing the HMAC, encrypt and decrypt operations and - * returns. The NULL seed is flushed before this function returns. + * Loads the ephemeral key (null seed), and starts an HMAC authenticated + * session. The null seed is flushed before the return. * - * Return: zero on success or actual error encountered. + * Returns zero on success, or a POSIX error code. */ int tpm2_start_auth_session(struct tpm_chip *chip) { @@ -1024,7 +1016,7 @@ int tpm2_start_auth_session(struct tpm_chip *chip) /* hash algorithm for session */ tpm_buf_append_u16(&buf, TPM_ALG_SHA256); - rc = tpm_transmit_cmd(chip, &buf, 0, "start auth session"); + rc = tpm_transmit_cmd(chip, &buf, 0, "StartAuthSession"); tpm2_flush_context(chip, null_key); if (rc == TPM2_RC_SUCCESS) @@ -1032,6 +1024,15 @@ int tpm2_start_auth_session(struct tpm_chip *chip) tpm_buf_destroy(&buf); + switch (rc) { + case TPM2_RC_SESSION_MEMORY: + rc = -ENOMEM; + goto out; + default: + rc = -EFAULT; + goto out; + } + if (rc == TPM2_RC_SUCCESS) { chip->auth = auth; return 0; diff --git a/include/linux/tpm.h b/include/linux/tpm.h index 6c3125300c00..c1d3d60b416f 100644 --- a/include/linux/tpm.h +++ b/include/linux/tpm.h @@ -257,6 +257,7 @@ enum tpm2_return_codes { TPM2_RC_TESTING = 0x090A, /* RC_WARN */ TPM2_RC_REFERENCE_H0 = 0x0910, TPM2_RC_RETRY = 0x0922, + TPM2_RC_SESSION_MEMORY = 0x0903, }; enum tpm2_command_codes {