From: Kent Yoder <key@linux.vnet.ibm.com>
Date: Thu, 5 Apr 2012 12:34:20 +0000 (+0800)
Subject: crypto: sha512 - Fix byte counter overflow in SHA-512
X-Git-Tag: v3.2.17~168
X-Git-Url: https://git.openpandora.org/cgi-bin/gitweb.cgi?p=pandora-kernel.git;a=commitdiff_plain;h=eea1acbaf0cd548972b40827c37667dcfdf5cbe5;ds=sidebyside

crypto: sha512 - Fix byte counter overflow in SHA-512

commit 25c3d30c918207556ae1d6e663150ebdf902186b upstream.

The current code only increments the upper 64 bits of the SHA-512 byte
counter when the number of bytes hashed happens to hit 2^64 exactly.

This patch increments the upper 64 bits whenever the lower 64 bits
overflows.

Signed-off-by: Kent Yoder <key@linux.vnet.ibm.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---

diff --git a/crypto/sha512_generic.c b/crypto/sha512_generic.c
index 107f6f7be5e1..dd30f40af9f5 100644
--- a/crypto/sha512_generic.c
+++ b/crypto/sha512_generic.c
@@ -174,7 +174,7 @@ sha512_update(struct shash_desc *desc, const u8 *data, unsigned int len)
 	index = sctx->count[0] & 0x7f;
 
 	/* Update number of bytes */
-	if (!(sctx->count[0] += len))
+	if ((sctx->count[0] += len) < len)
 		sctx->count[1]++;
 
         part_len = 128 - index;