[added to the 4.1 stable tree] crypto: ccp - Fix AES XTS error for request sizes above 4096

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



From: Tom Lendacky <thomas.lendacky@xxxxxxx>

This patch has been added to the 4.1 stable tree. If you have any
objections, please let us know.

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

[ Upstream commit ab6a11a7c8ef47f996974dd3c648c2c0b1a36ab1 ]

The ccp-crypto module for AES XTS support has a bug that can allow requests
greater than 4096 bytes in size to be passed to the CCP hardware. The CCP
hardware does not support request sizes larger than 4096, resulting in
incorrect output. The request should actually be handled by the fallback
mechanism instantiated by the ccp-crypto module.

Add a check to insure the request size is less than or equal to the maximum
supported size and use the fallback mechanism if it is not.

Cc: <stable@xxxxxxxxxxxxxxx> # 3.14.x-
Signed-off-by: Tom Lendacky <thomas.lendacky@xxxxxxx>
Signed-off-by: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sasha.levin@xxxxxxxxxx>
---
 drivers/crypto/ccp/ccp-crypto-aes-xts.c | 17 ++++++++++++-----
 1 file changed, 12 insertions(+), 5 deletions(-)

diff --git a/drivers/crypto/ccp/ccp-crypto-aes-xts.c b/drivers/crypto/ccp/ccp-crypto-aes-xts.c
index 52c7395..0d0d452 100644
--- a/drivers/crypto/ccp/ccp-crypto-aes-xts.c
+++ b/drivers/crypto/ccp/ccp-crypto-aes-xts.c
@@ -122,6 +122,7 @@ static int ccp_aes_xts_crypt(struct ablkcipher_request *req,
 	struct ccp_ctx *ctx = crypto_tfm_ctx(req->base.tfm);
 	struct ccp_aes_req_ctx *rctx = ablkcipher_request_ctx(req);
 	unsigned int unit;
+	u32 unit_size;
 	int ret;
 
 	if (!ctx->u.aes.key_len)
@@ -133,11 +134,17 @@ static int ccp_aes_xts_crypt(struct ablkcipher_request *req,
 	if (!req->info)
 		return -EINVAL;
 
-	for (unit = 0; unit < ARRAY_SIZE(unit_size_map); unit++)
-		if (!(req->nbytes & (unit_size_map[unit].size - 1)))
-			break;
+	unit_size = CCP_XTS_AES_UNIT_SIZE__LAST;
+	if (req->nbytes <= unit_size_map[0].size) {
+		for (unit = 0; unit < ARRAY_SIZE(unit_size_map); unit++) {
+			if (!(req->nbytes & (unit_size_map[unit].size - 1))) {
+				unit_size = unit_size_map[unit].value;
+				break;
+			}
+		}
+	}
 
-	if ((unit_size_map[unit].value == CCP_XTS_AES_UNIT_SIZE__LAST) ||
+	if ((unit_size == CCP_XTS_AES_UNIT_SIZE__LAST) ||
 	    (ctx->u.aes.key_len != AES_KEYSIZE_128)) {
 		/* Use the fallback to process the request for any
 		 * unsupported unit sizes or key sizes
@@ -158,7 +165,7 @@ static int ccp_aes_xts_crypt(struct ablkcipher_request *req,
 	rctx->cmd.engine = CCP_ENGINE_XTS_AES_128;
 	rctx->cmd.u.xts.action = (encrypt) ? CCP_AES_ACTION_ENCRYPT
 					   : CCP_AES_ACTION_DECRYPT;
-	rctx->cmd.u.xts.unit_size = unit_size_map[unit].value;
+	rctx->cmd.u.xts.unit_size = unit_size;
 	rctx->cmd.u.xts.key = &ctx->u.aes.key_sg;
 	rctx->cmd.u.xts.key_len = ctx->u.aes.key_len;
 	rctx->cmd.u.xts.iv = &rctx->iv_sg;
-- 
2.5.0

--
To unsubscribe from this list: send the line "unsubscribe stable" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html



[Index of Archives]     [Linux Kernel]     [Kernel Development Newbies]     [Linux USB Devel]     [Video for Linux]     [Linux Audio Users]     [Yosemite Hiking]     [Linux Kernel]     [Linux SCSI]