[PATCH 3.16.y-ckt 024/185] Revert "crypto: talitos - convert to use be16_add_cpu()"

[Luis Henriques]

3.16.7-ckt15 -stable review patch.  If anyone has any objections, please let me know.

------------------

From: Horia Geant? <horia.geanta at freescale.com>

commit 69d9cd8c592f1abce820dbce7181bbbf6812cfbd upstream.

This reverts commit 7291a932c6e27d9768e374e9d648086636daf61c.

The conversion to be16_add_cpu() is incorrect in case cryptlen is
negative due to premature (i.e. before addition / subtraction)
implicit conversion of cryptlen (int -> u16) leading to sign loss.

Cc: Wei Yongjun <yongjun_wei at trendmicro.com.cn>
Signed-off-by: Horia Geanta <horia.geanta at freescale.com>
Signed-off-by: Herbert Xu <herbert at gondor.apana.org.au>
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
 drivers/crypto/talitos.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/crypto/talitos.c b/drivers/crypto/talitos.c
index eb12caa8e94a..307931528eb2 100644
--- a/drivers/crypto/talitos.c
+++ b/drivers/crypto/talitos.c
@@ -927,7 +927,8 @@ static int sg_to_link_tbl(struct scatterlist *sg, int sg_count,
 		sg_count--;
 		link_tbl_ptr--;
 	}
-	be16_add_cpu(&link_tbl_ptr->len, cryptlen);
+	link_tbl_ptr->len = cpu_to_be16(be16_to_cpu(link_tbl_ptr->len)
+					+ cryptlen);
 
 	/* tag end of link table */
 	link_tbl_ptr->j_extent = DESC_PTR_LNKTBL_RETURN;