[PATCH 43/91] TPM: Call tpm_transmit with correct size

From: Willy Tarreau
Date: Sun Feb 05 2012 - 17:40:07 EST

2.6.27-longterm review patch. If anyone has any objections, please let us know.


commit 6b07d30aca7e52f2881b8c8c20c8a2cd28e8b3d3 upstream.

This patch changes the call of tpm_transmit by supplying the size of the
userspace buffer instead of TPM_BUFSIZE.

This got assigned CVE-2011-1161.

[The first hunk didn't make sense given one could expect
way less data than TPM_BUFSIZE, so added tpm_transmit boundary
check over bufsiz instead
The last parameter of tpm_transmit() reflects the amount
of data expected from the device, and not the buffer size
being supplied to it. It isn't ideal to parse it directly,
so we just set it to the maximum the input buffer can handle
and let the userspace API to do such job.]

Signed-off-by: Rajiv Andrade <srajiv@xxxxxxxxxxxxxxxxxx>
Signed-off-by: James Morris <jmorris@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxx>
drivers/char/tpm/tpm.c | 3 +++
1 files changed, 3 insertions(+), 0 deletions(-)

Index: longterm-2.6.27/drivers/char/tpm/tpm.c
--- longterm-2.6.27.orig/drivers/char/tpm/tpm.c 2012-02-05 22:34:33.730914904 +0100
+++ longterm-2.6.27/drivers/char/tpm/tpm.c 2012-02-05 22:34:40.951915689 +0100
@@ -375,6 +375,9 @@
u32 count, ordinal;
unsigned long stop;

+ if (bufsiz > TPM_BUFSIZE)
+ bufsiz = TPM_BUFSIZE;
count = be32_to_cpu(*((__be32 *) (buf + 2)));
ordinal = be32_to_cpu(*((__be32 *) (buf + 6)));
if (count == 0)

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