From 745860e1baa7f7f98b7119d488c066f3af8efdd2 Mon Sep 17 00:00:00 2001 From: Gilad Ben-Yossef Date: Tue, 15 Jan 2019 15:43:17 +0200 Subject: [PATCH] crypto: ccree - don't copy zero size ciphertext commit 2b5ac17463dcb2411fed506edcf259a89bb538ba upstream. For decryption in CBC mode we need to save the last ciphertext block for use as the next IV. However, we were trying to do this also with zero sized ciphertext resulting in a panic. Fix this by only doing the copy if the ciphertext length is at least of IV size. Signed-off-by: Gilad Ben-Yossef Cc: stable@vger.kernel.org Signed-off-by: Herbert Xu Signed-off-by: Greg Kroah-Hartman Signed-off-by: Yang Yingliang --- drivers/crypto/ccree/cc_cipher.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/crypto/ccree/cc_cipher.c b/drivers/crypto/ccree/cc_cipher.c index 7b9aa93544ba..54a39164aab8 100644 --- a/drivers/crypto/ccree/cc_cipher.c +++ b/drivers/crypto/ccree/cc_cipher.c @@ -783,7 +783,8 @@ static int cc_cipher_decrypt(struct skcipher_request *req) memset(req_ctx, 0, sizeof(*req_ctx)); - if (ctx_p->cipher_mode == DRV_CIPHER_CBC) { + if ((ctx_p->cipher_mode == DRV_CIPHER_CBC) && + (req->cryptlen >= ivsize)) { /* Allocate and save the last IV sized bytes of the source, * which will be lost in case of in-place decryption. -- GitLab