From 23966841934908ad4ef997231f1fdd1f9a9d0f42 Mon Sep 17 00:00:00 2001 From: Ard Biesheuvel Date: Fri, 16 Aug 2019 17:06:24 +0300 Subject: [PATCH] crypto: vmx/xts - use fallback for ciphertext stealing For correctness and compliance with the XTS-AES specification, we are adding support for ciphertext stealing to XTS implementations, even though no use cases are known that will be enabled by this. Since the Power8 implementation already has a fallback skcipher standby for other purposes, let's use it for this purpose as well. If ciphertext stealing use cases ever become a bottleneck, we can always revisit this. Signed-off-by: Ard Biesheuvel Signed-off-by: Herbert Xu --- drivers/crypto/vmx/aes_xts.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/crypto/vmx/aes_xts.c b/drivers/crypto/vmx/aes_xts.c index 49f7258045fa..d59e736882f6 100644 --- a/drivers/crypto/vmx/aes_xts.c +++ b/drivers/crypto/vmx/aes_xts.c @@ -84,7 +84,7 @@ static int p8_aes_xts_crypt(struct skcipher_request *req, int enc) u8 tweak[AES_BLOCK_SIZE]; int ret; - if (!crypto_simd_usable()) { + if (!crypto_simd_usable() || (req->cryptlen % XTS_BLOCK_SIZE) != 0) { struct skcipher_request *subreq = skcipher_request_ctx(req); *subreq = *req; -- 2.30.2