Patch "crypto: nx - Fix timing leak in GCM and CCM decryption" has been added to the 4.3-stable tree
Subsystems (4)
This is a note to let you know that I've just added the patch titled
crypto: nx - Fix timing leak in GCM and CCM decryption
to the 4.3-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
crypto-nx-fix-timing-leak-in-gcm-and-ccm-decryption.patch
and it can be found in the queue-4.3 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.
Quoted 1 line
From
cb8affb55c7e64816f3effcd9b2fc3268c016facMon Sep 17 00:00:00 2001
From: David Gstir <[email protected]>
Date: Sun, 15 Nov 2015 17:14:41 +0100
Subject: crypto: nx - Fix timing leak in GCM and CCM decryption
From: David Gstir <[email protected]>
commit cb8affb55c7e64816f3effcd9b2fc3268c016fac upstream.
Using non-constant time memcmp() makes the verification of the authentication tag in the decrypt path vulnerable to timing attacks. Fix this by using crypto_memneq() instead.
--- drivers/crypto/nx/nx-aes-ccm.c | 2 +- drivers/crypto/nx/nx-aes-gcm.c | 3 ++- 2 files changed, 3 insertions(+), 2 deletions(-)
drivers/crypto/nx/nx-aes-ccm.c +1 -1
@@ -409,7 +409,7 @@ static int ccm_nx_decrypt(struct aead_re processed += to_process; }while (processed < nbytes); - rc =memcmp (csbcpb->cpb.aes_ccm.out_pat_or_mac, priv->oauth_tag, + rc =crypto_memneq (csbcpb->cpb.aes_ccm.out_pat_or_mac, priv->oauth_tag, authsize) ? -EBADMSG :0 ; out:spin_unlock_irqrestore (&nx_ctx->lock, irq_flags);
drivers/crypto/nx/nx-aes-gcm.c +2 -1
@@ -21,6 +21,7 @@#include <crypto/internal/aead.h> #include <crypto/aes.h> +#include <crypto/algapi.h> #include <crypto/scatterwalk.h> #include <linux/module.h> #include <linux/types.h>
@@ -418,7 +419,7 @@ mac: itag, req->src, req->assoclen + nbytes,crypto_aead_authsize (crypto_aead_reqtfm (req)), SCATTERWALK_FROM_SG); - rc =memcmp (itag, otag, + rc =crypto_memneq (itag, otag,crypto_aead_authsize (crypto_aead_reqtfm (req))) ? -EBADMSG :0 ; }
Patches currently in stable-queue which might be from [email protected] are
queue-4.3/crypto-nx-fix-timing-leak-in-gcm-and-ccm-decryption.patch queue-4.3/crypto-talitos-fix-timing-leak-in-esp-icv-verification.patch