[PATCH] tpm: Fix expected number of response bytes of TPM1.2 PCR Extend

From	Stefan Berger <stefanb@linux.vnet.ibm.com>
Newsgroups	linux.kernel
Subject	[PATCH] tpm: Fix expected number of response bytes of TPM1.2 PCR Extend
Date	2017-02-15 18:00 +0100
Message-ID	<tbb5U-2sv-25@gated-at.bofh.it> (permalink)
Organization	linux.* mail to news gateway

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The TPM1.2 PCR Extend operation only returns 20 bytes in the body,
which is the size of the PCR state.

This fixes a problem where IMA gets errors with every PCR Extend.

Fixes: c659af78eb7b ("tpm: Check size of response before accessing data")
Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
Acked-by: Mimi Zohar <zohar@us.ibm.com>
---
 drivers/char/tpm/tpm-interface.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c
index 6e368ee..bd2128e 100644
--- a/drivers/char/tpm/tpm-interface.c
+++ b/drivers/char/tpm/tpm-interface.c
@@ -767,7 +767,7 @@ EXPORT_SYMBOL_GPL(tpm_pcr_read);
 
 #define TPM_ORD_PCR_EXTEND cpu_to_be32(20)
 #define EXTEND_PCR_RESULT_SIZE 34
-#define EXTEND_PCR_RESULT_BODY_SIZE 24
+#define EXTEND_PCR_RESULT_BODY_SIZE 20
 static const struct tpm_input_header pcrextend_header = {
 	.tag = TPM_TAG_RQU_COMMAND,
 	.length = cpu_to_be32(34),
-- 
2.4.3

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[PATCH] tpm: Fix expected number of response bytes of TPM1.2 PCR Extend Stefan Berger <stefanb@linux.vnet.ibm.com> - 2017-02-15 18:00 +0100
  Re: [PATCH] tpm: Fix expected number of response bytes of TPM1.2 PCR  Extend Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> - 2017-02-15 19:10 +0100
    Re: [PATCH] tpm: Fix expected number of response bytes of TPM1.2  PCR Extend Mimi Zohar <zohar@linux.vnet.ibm.com> - 2017-02-17 13:50 +0100
      Re: [PATCH] tpm: Fix expected number of response bytes of TPM1.2 PCR  Extend Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> - 2017-02-17 19:50 +0100
        Re: [PATCH] tpm: Fix expected number of response bytes of TPM1.2  PCR Extend Mimi Zohar <zohar@linux.vnet.ibm.com> - 2017-02-17 20:00 +0100

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