From patchwork Tue Jul 16 18:52:24 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jarkko Sakkinen X-Patchwork-Id: 13734769 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 3D42B1643A; Tue, 16 Jul 2024 18:52:34 +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=1721155955; cv=none; b=ecqTbOZVmFy4nWnck6eNPFvEb9+d5TW31BGMkEoTXu74BIBkM/mF/ZtKE5xQCD9XNnmBHZGlajwlSkbroZ9tvMC8ljOCbmFH8d2Kf89WvTUhGbIfXJsApSMzsy1xu6ILB+gufBfs7/Xk16hqlnxzQ2EiKiJq+H643O8g2fyJQlI= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1721155955; c=relaxed/simple; bh=X9OpwdZtZFTZbbC8V7nGKukaKQcflFFBotd4UiiS6jk=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=RT+Sfzz0t6RvqT0Zu3pW0A/RMYNjvhCVy+PvU0Xk3SVs+/4DadnpnkA4M2xVX8wL/DU+4VpJk5P2q6HuBvojXuUtbYee49cS/v0LEvjabcMYnHbGe0K2f+KVwrORb+LjDvYjppAOU7OnlkiyRWp54PS+JbUfV/81Mx4CfUKXVec= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Btv5GK+G; 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="Btv5GK+G" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 394C8C116B1; Tue, 16 Jul 2024 18:52:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1721155954; bh=X9OpwdZtZFTZbbC8V7nGKukaKQcflFFBotd4UiiS6jk=; h=From:To:Cc:Subject:Date:From; b=Btv5GK+GHpWpFgNUGAXhwF491WnEU1qSMBJhT0aqTx3Wo0FiUPDwzz6DMf0TEcKfP 69Wiqt0ydpi9IoNxqSCEHKcJQzlQ7EGH9XfSUeA+PxHkJXRNHhvLGw/9off8twSSfV RUL2dfcD7qcQozPy666ljreu4OgKwn6rK0mxbYFV1X/zahQq6tPGks0AKtNDO2PtCB DMISNjOAqeojj1esoLn04dkScVrDQ0cTw82ACQtmOVK4xqNTmb+VFdnRHHHeKboz2i JJ3BX/2fPHIA//3uDPy0EkZKWXzivS7bWvyQ7AO2snIm9xtfCw9UksZLgOqcoyEJ2O wBUwOlPNB3rsQ== From: Jarkko Sakkinen To: linux-integrity@vger.kernel.org Cc: Jarkko Sakkinen , stable@vger.kernel.org, James Bottomley , Mimi Zohar , David Howells , Paul Moore , James Morris , "Serge E. Hallyn" , keyrings@vger.kernel.org, linux-security-module@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v3] tpm: Relocate buf->handles to appropriate place Date: Tue, 16 Jul 2024 21:52:24 +0300 Message-ID: <20240716185225.873090-1-jarkko@kernel.org> X-Mailer: git-send-email 2.45.2 Precedence: bulk X-Mailing-List: linux-security-module@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 tpm_buf_append_name() has the following snippet in the beginning: if (!tpm2_chip_auth(chip)) { tpm_buf_append_u32(buf, handle); /* count the number of handles in the upper bits of flags */ buf->handles++; return; } The claim in the comment is wrong, and the comment is in the wrong place as alignment in this case should not anyway be a concern of the call site. In essence the comment is lying about the code, and thus needs to be adressed. Further, 'handles' was incorrectly place to struct tpm_buf, as tpm-buf.c does manage its state. It is easy to grep that only piece of code that actually uses the field is tpm2-sessions.c. Address the issues by moving the variable to struct tpm_chip. Cc: stable@vger.kernel.org # v6.10+ Fixes: 699e3efd6c64 ("tpm: Add HMAC session start and end functions") Signed-off-by: Jarkko Sakkinen v3: * Reset chip->handles in the beginning of tpm2_start_auth_session() so that it shows correct value, when TCG_TPM2_HMAC is enabled but tpm2_sessions_init() has never been called. v2: * Was a bit more broken than I first thought, as 'handles' is only useful for tpm2-sessions.c and has zero relation to tpm-buf.c. --- drivers/char/tpm/tpm-buf.c | 1 - drivers/char/tpm/tpm2-cmd.c | 2 +- drivers/char/tpm/tpm2-sessions.c | 7 ++++--- include/linux/tpm.h | 8 ++++---- 4 files changed, 9 insertions(+), 9 deletions(-) diff --git a/drivers/char/tpm/tpm-buf.c b/drivers/char/tpm/tpm-buf.c index cad0048bcc3c..d06e8e063151 100644 --- a/drivers/char/tpm/tpm-buf.c +++ b/drivers/char/tpm/tpm-buf.c @@ -44,7 +44,6 @@ void tpm_buf_reset(struct tpm_buf *buf, u16 tag, u32 ordinal) head->tag = cpu_to_be16(tag); head->length = cpu_to_be32(sizeof(*head)); head->ordinal = cpu_to_be32(ordinal); - buf->handles = 0; } EXPORT_SYMBOL_GPL(tpm_buf_reset); diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c index 1e856259219e..b781e4406fc2 100644 --- a/drivers/char/tpm/tpm2-cmd.c +++ b/drivers/char/tpm/tpm2-cmd.c @@ -776,7 +776,7 @@ int tpm2_auto_startup(struct tpm_chip *chip) if (rc) goto out; - rc = tpm2_sessions_init(chip); + /* rc = tpm2_sessions_init(chip); */ out: /* diff --git a/drivers/char/tpm/tpm2-sessions.c b/drivers/char/tpm/tpm2-sessions.c index d3521aadd43e..5e7c12d64ba8 100644 --- a/drivers/char/tpm/tpm2-sessions.c +++ b/drivers/char/tpm/tpm2-sessions.c @@ -238,8 +238,7 @@ void tpm_buf_append_name(struct tpm_chip *chip, struct tpm_buf *buf, if (!tpm2_chip_auth(chip)) { tpm_buf_append_u32(buf, handle); - /* count the number of handles in the upper bits of flags */ - buf->handles++; + chip->handles++; return; } @@ -310,7 +309,7 @@ void tpm_buf_append_hmac_session(struct tpm_chip *chip, struct tpm_buf *buf, if (!tpm2_chip_auth(chip)) { /* offset tells us where the sessions area begins */ - int offset = buf->handles * 4 + TPM_HEADER_SIZE; + int offset = chip->handles * 4 + TPM_HEADER_SIZE; u32 len = 9 + passphrase_len; if (tpm_buf_length(buf) != offset) { @@ -963,6 +962,8 @@ int tpm2_start_auth_session(struct tpm_chip *chip) int rc; u32 null_key; + chip->handles = 0; + if (!auth) { dev_warn_once(&chip->dev, "auth session is not active\n"); return 0; diff --git a/include/linux/tpm.h b/include/linux/tpm.h index e93ee8d936a9..b664f7556494 100644 --- a/include/linux/tpm.h +++ b/include/linux/tpm.h @@ -202,9 +202,9 @@ struct tpm_chip { /* active locality */ int locality; + /* handle count for session: */ + u8 handles; #ifdef CONFIG_TCG_TPM2_HMAC - /* details for communication security via sessions */ - /* saved context for NULL seed */ u8 null_key_context[TPM2_MAX_CONTEXT_SIZE]; /* name of NULL seed */ @@ -377,7 +377,6 @@ struct tpm_buf { u32 flags; u32 length; u8 *data; - u8 handles; }; enum tpm2_object_attributes { @@ -517,7 +516,7 @@ static inline void tpm_buf_append_hmac_session_opt(struct tpm_chip *chip, if (tpm2_chip_auth(chip)) { tpm_buf_append_hmac_session(chip, buf, attributes, passphrase, passphraselen); } else { - offset = buf->handles * 4 + TPM_HEADER_SIZE; + offset = chip->handles * 4 + TPM_HEADER_SIZE; head = (struct tpm_header *)buf->data; /* @@ -541,6 +540,7 @@ void tpm2_end_auth_session(struct tpm_chip *chip); static inline int tpm2_start_auth_session(struct tpm_chip *chip) { + chip->handles = 0; return 0; } static inline void tpm2_end_auth_session(struct tpm_chip *chip)