[PATCH 3.12 087/155] crypto: s390 - fix aes,des ctr mode concurrency finding.

[Jiri Slaby]

From: Harald Freudenberger <freude@xxxxxxxxxxxxxxxxxx>

3.12-stable review patch.  If anyone has any objections, please let me know.

===============

commit 3901c1124ec5099254a9396085f7798153a7293f upstream.

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.

Cc: <stable@xxxxxxxxxxxxxxx> # 3.14+
Signed-off-by: Harald Freudenberger <freude@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Jiri Slaby <jslaby@xxxxxxx>
---
 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 f8d9cb14adce..92eb4d6ad39d 100644
--- a/arch/s390/crypto/aes_s390.c
+++ b/arch/s390/crypto/aes_s390.c
@@ -818,6 +818,9 @@ 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 a3e24d4d2530..a89feffb22b5 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) {
-- 
2.3.4

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