2014-05-07 14:51:29

by Harald Freudenberger

[permalink] [raw]
Subject: [PATCH] s390/crypto: fix aes,des ctr mode concurrency finding.

An additional testcase found an issue with the last
series of patches applied: the fallback solution may
not save the iv value after operation. This very small
fix just makes sure the iv is copied back to the
walk/desc struct.

Signed-off-by: Harald Freudenberger <[email protected]>
---
arch/s390/crypto/aes_s390.c | 3 +++
arch/s390/crypto/des_s390.c | 3 +++
2 files changed, 6 insertions(+)

diff --git a/arch/s390/crypto/aes_s390.c b/arch/s390/crypto/aes_s390.c
index cf3c008..23223cd 100644
--- a/arch/s390/crypto/aes_s390.c
+++ b/arch/s390/crypto/aes_s390.c
@@ -820,6 +820,9 @@ static int ctr_aes_crypt(struct blkcipher_desc *desc, long func,
else
memcpy(walk->iv, ctrptr, AES_BLOCK_SIZE);
spin_unlock(&ctrblk_lock);
+ } else {
+ if (!nbytes)
+ memcpy(walk->iv, ctrptr, AES_BLOCK_SIZE);
}
/*
* final block may be < AES_BLOCK_SIZE, copy only nbytes
diff --git a/arch/s390/crypto/des_s390.c b/arch/s390/crypto/des_s390.c
index 0a5aac8..7acb77f 100644
--- a/arch/s390/crypto/des_s390.c
+++ b/arch/s390/crypto/des_s390.c
@@ -429,6 +429,9 @@ static int ctr_desall_crypt(struct blkcipher_desc *desc, long func,
else
memcpy(walk->iv, ctrptr, DES_BLOCK_SIZE);
spin_unlock(&ctrblk_lock);
+ } else {
+ if (!nbytes)
+ memcpy(walk->iv, ctrptr, DES_BLOCK_SIZE);
}
/* final block may be < DES_BLOCK_SIZE, copy only nbytes */
if (nbytes) {
--
1.7.9.5


2014-05-08 14:02:11

by Herbert Xu

[permalink] [raw]
Subject: Re: [PATCH] s390/crypto: fix aes,des ctr mode concurrency finding.

On Wed, May 07, 2014 at 04:51:29PM +0200, Harald Freudenberger wrote:
> An additional testcase found an issue with the last
> series of patches applied: the fallback solution may
> not save the iv value after operation. This very small
> fix just makes sure the iv is copied back to the
> walk/desc struct.
>
> Signed-off-by: Harald Freudenberger <[email protected]>

Patch applied to crypto. Thanks!
--
Email: Herbert Xu <[email protected]>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt