linux-kernel - Re: [PATCH v4 1/4] tpm: migrate tpm2_shutdown() to use struct tpm

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20180518223032.ihszdef5wesj5nie@cantor>
Date:   Fri, 18 May 2018 15:30:32 -0700
From:   Jerry Snitselaar <jsnitsel@...hat.com>
To:     Jarkko Sakkinen <jarkko.sakkinen@...ux.intel.com>
Cc:     linux-integrity@...r.kernel.org,
        linux-security-module@...r.kernel.org,
        Peter Huewe <peterhuewe@....de>,
        Jason Gunthorpe <jgg@...pe.ca>, Arnd Bergmann <arnd@...db.de>,
        Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        open list <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH v4 1/4] tpm: migrate tpm2_shutdown() to use struct tpm_buf

On Mon Mar 26 18, Jarkko Sakkinen wrote:
>In order to make struct tpm_buf the first class object for constructing TPM
>commands, migrate tpm2_shutdown() to use it. In addition, removed the klog
>entry when tpm_transmit_cmd() fails because tpm_tansmit_cmd() already
>prints an error message.
>
>Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@...ux.intel.com>

Reviewed-by: Jerry Snitselaar <jsnitsel@...hat.com>

>---
> drivers/char/tpm/tpm2-cmd.c | 44 ++++++++++++--------------------------------
> 1 file changed, 12 insertions(+), 32 deletions(-)
>
>diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c
>index 96c77c8e7f40..7665661d9230 100644
>--- a/drivers/char/tpm/tpm2-cmd.c
>+++ b/drivers/char/tpm/tpm2-cmd.c
>@@ -27,10 +27,6 @@ enum tpm2_session_attributes {
> 	TPM2_SA_CONTINUE_SESSION	= BIT(0),
> };
>
>-struct tpm2_startup_in {
>-	__be16	startup_type;
>-} __packed;
>-
> struct tpm2_get_tpm_pt_in {
> 	__be32	cap_id;
> 	__be32	property_id;
>@@ -55,7 +51,6 @@ struct tpm2_get_random_out {
> } __packed;
>
> union tpm2_cmd_params {
>-	struct	tpm2_startup_in		startup_in;
> 	struct	tpm2_get_tpm_pt_in	get_tpm_pt_in;
> 	struct	tpm2_get_tpm_pt_out	get_tpm_pt_out;
> 	struct	tpm2_get_random_in	getrandom_in;
>@@ -412,11 +407,8 @@ void tpm2_flush_context_cmd(struct tpm_chip *chip, u32 handle,
> 	int rc;
>
> 	rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_FLUSH_CONTEXT);
>-	if (rc) {
>-		dev_warn(&chip->dev, "0x%08x was not flushed, out of memory\n",
>-			 handle);
>+	if (rc)
> 		return;
>-	}
>
> 	tpm_buf_append_u32(&buf, handle);
>
>@@ -762,40 +754,28 @@ ssize_t tpm2_get_tpm_pt(struct tpm_chip *chip, u32 property_id,  u32 *value,
> }
> EXPORT_SYMBOL_GPL(tpm2_get_tpm_pt);
>
>-#define TPM2_SHUTDOWN_IN_SIZE \
>-	(sizeof(struct tpm_input_header) + \
>-	 sizeof(struct tpm2_startup_in))
>-
>-static const struct tpm_input_header tpm2_shutdown_header = {
>-	.tag = cpu_to_be16(TPM2_ST_NO_SESSIONS),
>-	.length = cpu_to_be32(TPM2_SHUTDOWN_IN_SIZE),
>-	.ordinal = cpu_to_be32(TPM2_CC_SHUTDOWN)
>-};
>-
> /**
>  * tpm2_shutdown() - send shutdown command to the TPM chip
>  *
>+ * In places where shutdown command is sent there's no much we can do except
>+ * print the error code on a system failure.
>+ *
>  * @chip:		TPM chip to use.
>  * @shutdown_type:	shutdown type. The value is either
>  *			TPM_SU_CLEAR or TPM_SU_STATE.
>  */
> void tpm2_shutdown(struct tpm_chip *chip, u16 shutdown_type)
> {
>-	struct tpm2_cmd cmd;
>+	struct tpm_buf buf;
> 	int rc;
>
>-	cmd.header.in = tpm2_shutdown_header;
>-	cmd.params.startup_in.startup_type = cpu_to_be16(shutdown_type);
>-
>-	rc = tpm_transmit_cmd(chip, NULL, &cmd, sizeof(cmd), 0, 0,
>-			      "stopping the TPM");
>-
>-	/* In places where shutdown command is sent there's no much we can do
>-	 * except print the error code on a system failure.
>-	 */
>-	if (rc < 0 && rc != -EPIPE)
>-		dev_warn(&chip->dev, "transmit returned %d while stopping the TPM",
>-			 rc);
>+	rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_SHUTDOWN);
>+	if (rc)
>+		return;
>+	tpm_buf_append_u16(&buf, shutdown_type);
>+	tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 0, 0,
>+			 "stopping the TPM");
>+	tpm_buf_destroy(&buf);
> }
>
> /*
>-- 
>2.15.1
>