From patchwork Mon Sep 16 11:07:11 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jarkko Sakkinen X-Patchwork-Id: 13805286 X-Patchwork-Delegate: paul@paul-moore.com 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 3992714E2DA; Mon, 16 Sep 2024 11:07:48 +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=1726484868; cv=none; b=hc2F81Pc0xW8UXNpyawjJzPxGC6b8fG4TatzCC8aF5/OT8WOCByOFcJSXemIvvhP6gZop3HDzp+lvdWYA+rLUh/x6LZHhrvMYB9Yi2INmK1udi63LAhqrg6ACMfB5TMqOWj2ycUxGRw5GtNicGkKnw65bt6prFeptEdDE8N5pZk= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1726484868; c=relaxed/simple; bh=xD2s5On1ZCWWzafhSszKhanrFM8TIDWSq6PdNHlzYy0=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=nANs7SNLPQr/lvGKp2aRioyHycv1Qaw3ozC4Ycen5TpIBO7VPZVQ6gqJ8IlGzph+uKbjRyK3DJcTZaT9O0mlnJfTMqopEB47ZYPiCtFxjldh25ACiS6jtI1VpKxtxQm5LO8QCNa0DVK2wGNoH6esmjCYrwWZtfzX8avTC9OrCvw= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=AY0jUZP5; 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="AY0jUZP5" Received: by smtp.kernel.org (Postfix) with ESMTPSA id B7251C4CEC4; Mon, 16 Sep 2024 11:07:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1726484868; bh=xD2s5On1ZCWWzafhSszKhanrFM8TIDWSq6PdNHlzYy0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=AY0jUZP5uKNbnY5Z8u9a6VGpH+29Fu+8WquuEtw3+rXhKUC7QWKx2b4USwVrhInDH m/EbDH33kcy2drqRApYKAZTe7ccQGnXeWmMAsmYA2sMJ4D6o7Wtqb2/Tum+9+s58iF fhixB1bh2UNfyZ4TaE0F4FJFDBVrWqBkssb0W9jyuMxAskhzveCqLsBT/+tW4qx11E ZoU8MpjO0zqw7/66DE7H0fvQxemxbwsMzbjiYVXvx3OhMc4STH8fkZme24iBdzH7n1 gQRI4Co0YUDx9z26/Ny/DsuJ1RCDoKrcRQ6s5gQUw9667/G+r5r6YxFFR9zeXC6DfC uLzUK1ql7nIlQ== From: Jarkko Sakkinen To: linux-integrity@vger.kernel.org Cc: James.Bottomley@HansenPartnership.com, roberto.sassu@huawei.com, mapengyu@gmail.com, Jarkko Sakkinen , Peter Huewe , Jason Gunthorpe , Mimi Zohar , David Howells , Paul Moore , James Morris , "Serge E. Hallyn" , linux-kernel@vger.kernel.org (open list), keyrings@vger.kernel.org (open list:KEYS-TRUSTED), linux-security-module@vger.kernel.org (open list:SECURITY SUBSYSTEM) Subject: [PATCH v2 6/6] tpm: flush the auth session only when /dev/tpm0 is open Date: Mon, 16 Sep 2024 14:07:11 +0300 Message-ID: <20240916110714.1396407-7-jarkko@kernel.org> X-Mailer: git-send-email 2.46.0 In-Reply-To: <20240916110714.1396407-1-jarkko@kernel.org> References: <20240916110714.1396407-1-jarkko@kernel.org> Precedence: bulk X-Mailing-List: linux-security-module@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Instead of flushing and reloading the auth session for every single transaction, keep the session open unless /dev/tpm0 is open. In practice this means applying TPM2_SA_CONTINUE_SESSION to the session attributes. Flush the session always when /dev/tpm0 is written. Signed-off-by: Jarkko Sakkinen --- drivers/char/tpm/tpm-chip.c | 1 + drivers/char/tpm/tpm-dev-common.c | 1 + drivers/char/tpm/tpm-interface.c | 1 + drivers/char/tpm/tpm2-sessions.c | 4 ++++ 4 files changed, 7 insertions(+) diff --git a/drivers/char/tpm/tpm-chip.c b/drivers/char/tpm/tpm-chip.c index 0ea00e32f575..7a6bb30d1f32 100644 --- a/drivers/char/tpm/tpm-chip.c +++ b/drivers/char/tpm/tpm-chip.c @@ -680,6 +680,7 @@ void tpm_chip_unregister(struct tpm_chip *chip) rc = tpm_try_get_ops(chip); if (!rc) { if (chip->flags & TPM_CHIP_FLAG_TPM2) { + tpm2_end_auth_session(chip); tpm2_flush_context(chip, chip->null_key); chip->null_key = 0; } diff --git a/drivers/char/tpm/tpm-dev-common.c b/drivers/char/tpm/tpm-dev-common.c index 4bc07963e260..c6fdeb4feaef 100644 --- a/drivers/char/tpm/tpm-dev-common.c +++ b/drivers/char/tpm/tpm-dev-common.c @@ -29,6 +29,7 @@ static ssize_t tpm_dev_transmit(struct tpm_chip *chip, struct tpm_space *space, #ifdef CONFIG_TCG_TPM2_HMAC if (chip->flags & TPM_CHIP_FLAG_TPM2) { + tpm2_end_auth_session(chip); tpm2_flush_context(chip, chip->null_key); chip->null_key = 0; } diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c index bfa47d48b0f2..2363018fa8fb 100644 --- a/drivers/char/tpm/tpm-interface.c +++ b/drivers/char/tpm/tpm-interface.c @@ -381,6 +381,7 @@ int tpm_pm_suspend(struct device *dev) if (!rc) { if (chip->flags & TPM_CHIP_FLAG_TPM2) { #ifdef CONFIG_TCG_TPM2_HMAC + tpm2_end_auth_session(chip); tpm2_flush_context(chip, chip->null_key); chip->null_key = 0; #endif diff --git a/drivers/char/tpm/tpm2-sessions.c b/drivers/char/tpm/tpm2-sessions.c index f7746a165695..efe4b0017a83 100644 --- a/drivers/char/tpm/tpm2-sessions.c +++ b/drivers/char/tpm/tpm2-sessions.c @@ -268,6 +268,10 @@ void tpm_buf_append_hmac_session(struct tpm_chip *chip, struct tpm_buf *buf, } #ifdef CONFIG_TCG_TPM2_HMAC + /* The first write to /dev/tpm{rm0} will flush the session. */ + if (!chip->is_open) + attributes |= TPM2_SA_CONTINUE_SESSION; + /* * The Architecture Guide requires us to strip trailing zeros * before computing the HMAC