From: Peter Huewe <huewe.external.infineon@googlemail.com>
Date: Tue, 29 Mar 2011 11:31:25 +0000 (+0200)
Subject: char/tpm: Fix unitialized usage of data buffer
X-Git-Tag: v2.6.27.59~37
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=41385335037eacc75754297216191d0a1a32dcc7;p=thirdparty%2Fkernel%2Fstable.git

char/tpm: Fix unitialized usage of data buffer

commit 1309d7afbed112f0e8e90be9af975550caa0076b upstream.

This patch fixes information leakage to the userspace by initializing
the data buffer to zero.

Reported-by: Peter Huewe <huewe.external@infineon.com>
Signed-off-by: Peter Huewe <huewe.external@infineon.com>
Signed-off-by: Marcel Selhorst <m.selhorst@sirrix.com>
[ Also removed the silly "* sizeof(u8)".  If that isn't 1, we have way
  deeper problems than a simple multiplication can fix.   - Linus ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
---

diff --git a/drivers/char/tpm/tpm.c b/drivers/char/tpm/tpm.c
index 50cd8fa2008b5..cc4f1778bab4c 100644
--- a/drivers/char/tpm/tpm.c
+++ b/drivers/char/tpm/tpm.c
@@ -988,7 +988,7 @@ int tpm_open(struct inode *inode, struct file *file)
 
 	spin_unlock(&driver_lock);
 
-	chip->data_buffer = kmalloc(TPM_BUFSIZE * sizeof(u8), GFP_KERNEL);
+	chip->data_buffer = kzalloc(TPM_BUFSIZE, GFP_KERNEL);
 	if (chip->data_buffer == NULL) {
 		chip->num_opens--;
 		put_device(chip->dev);