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[3.19.y-ckt,stable] Patch "crypto: nx - Fix timing leak in GCM and CCM decryption" has been added to staging queue

Message ID 1450221411-5029-1-git-send-email-kamal@canonical.com
State New
Headers show

Commit Message

Kamal Mostafa Dec. 15, 2015, 11:16 p.m. UTC 
This is a note to let you know that I have just added a patch titled

    crypto: nx - Fix timing leak in GCM and CCM decryption

to the linux-3.19.y-queue branch of the 3.19.y-ckt extended stable tree 
which can be found at:

    http://kernel.ubuntu.com/git/ubuntu/linux.git/log/?h=linux-3.19.y-queue

This patch is scheduled to be released in version 3.19.8-ckt12.

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.19.y-ckt tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Kamal

------

From 5ef3d4b2b533e90ea793ab49d61515822ca228a1 Mon Sep 17 00:00:00 2001
From: David Gstir <david@sigma-star.at>
Date: Sun, 15 Nov 2015 17:14:41 +0100
Subject: crypto: nx - Fix timing leak in GCM and CCM decryption

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.

Signed-off-by: David Gstir <david@sigma-star.at>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
---
 drivers/crypto/nx/nx-aes-ccm.c | 2 +-
 drivers/crypto/nx/nx-aes-gcm.c | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

--
1.9.1
diff mbox

Patch

diff --git a/drivers/crypto/nx/nx-aes-ccm.c b/drivers/crypto/nx/nx-aes-ccm.c
index 67f8081..40992a2 100644
--- a/drivers/crypto/nx/nx-aes-ccm.c
+++ b/drivers/crypto/nx/nx-aes-ccm.c
@@ -412,7 +412,7 @@  static int ccm_nx_decrypt(struct aead_request   *req,
 		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);
diff --git a/drivers/crypto/nx/nx-aes-gcm.c b/drivers/crypto/nx/nx-aes-gcm.c
index 88c5624..ae4561d 100644
--- a/drivers/crypto/nx/nx-aes-gcm.c
+++ b/drivers/crypto/nx/nx-aes-gcm.c
@@ -423,7 +423,7 @@  mac:
 		scatterwalk_map_and_copy(itag, req->src, 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;
 	}