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: v2.6.34.15~2
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=9407270c29e59a669c77b8e31fb901561b7d7682;p=thirdparty%2Fkernel%2Fstable.git

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: Paul Gortmaker <paul.gortmaker@windriver.com>
---

diff --git a/crypto/sha512_generic.c b/crypto/sha512_generic.c
index 9ed9f60316e54..899b2fa24e50e 100644
--- a/crypto/sha512_generic.c
+++ b/crypto/sha512_generic.c
@@ -177,7 +177,7 @@ 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;