patch "crypto: asym_tpm: correct zero out potential secrets" added to char-misc-linus - Linux-stable-mirror

31 Dec 2020

This is a note to let you know that I've just added the patch titled
crypto: asym_tpm: correct zero out potential secrets
to my char-misc git tree which can be found at
    git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc.git
in the char-misc-linus branch.
The patch will show up in the next release of the linux-next tree
(usually sometime within the next 24 hours during the week.)
The patch will hopefully also be merged in Linus's tree for the
next -rc kernel release.
If you have any questions about this process, please let me know.
...
From f93274ef0fe972c120c96b3207f8fce376231a60 Mon Sep 17 00:00:00 2001
From: Greg Kroah-Hartman gregkh@linuxfoundation.org
Date: Fri, 4 Dec 2020 09:01:36 +0100
Subject: crypto: asym_tpm: correct zero out potential secrets
The function derive_pub_key() should be calling memzero_explicit()
instead of memset() in case the complier decides to optimize away the
call to memset() because it "knows" no one is going to touch the memory
anymore.
Cc: stable stable@vger.kernel.org
Reported-by: Ilil Blum Shem-Tov ilil.blum.shem-tov@intel.com
Tested-by: Ilil Blum Shem-Tov ilil.blum.shem-tov@intel.com
Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
Link: https://lore.kernel.org/r/X8ns4AfwjKudpyfe@kroah.com
Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
---
 crypto/asymmetric_keys/asym_tpm.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/crypto/asymmetric_keys/asym_tpm.c b/crypto/asymmetric_keys/asym_tpm.c
index 511932aa94a6..0959613560b9 100644
--- a/crypto/asymmetric_keys/asym_tpm.c
+++ b/crypto/asymmetric_keys/asym_tpm.c
@@ -354,7 +354,7 @@ static uint32_t derive_pub_key(const void *pub_key, uint32_t len, uint8_t *buf)
    memcpy(cur, e, sizeof(e));
    cur += sizeof(e);
    /* Zero parameters to satisfy set_pub_key ABI. */
-	memset(cur, 0, SETKEY_PARAMS_SIZE);
+	memzero_explicit(cur, SETKEY_PARAMS_SIZE);
return cur - buf;
 }
-- 
2.30.0



    