[PATCH 5.0 017/238] crypto: ccree - unmap buffer before copying IV

From: Greg Kroah-Hartman
Date: Fri Mar 22 2019 - 08:35:49 EST

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


From: Gilad Ben-Yossef <gilad@xxxxxxxxxxxxx>

commit c139c72e2beb3e3db5148910b3962b7322e24374 upstream.

We were copying the last ciphertext block into the IV field
for CBC before removing the DMA mapping of the output buffer
with the result of the buffer sometime being out-of-sync cache
wise and were getting intermittent cases of bad output IV.

Fix it by moving the DMA buffer unmapping before the copy.

Signed-off-by: Gilad Ben-Yossef <gilad@xxxxxxxxxxxxx>
Fixes: 00904aa0cd59 ("crypto: ccree - fix iv handling")
Cc: <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

drivers/crypto/ccree/cc_cipher.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

--- a/drivers/crypto/ccree/cc_cipher.c
+++ b/drivers/crypto/ccree/cc_cipher.c
@@ -653,6 +653,8 @@ static void cc_cipher_complete(struct de
unsigned int ivsize = crypto_skcipher_ivsize(sk_tfm);
unsigned int len;

+ cc_unmap_cipher_request(dev, req_ctx, ivsize, src, dst);
switch (ctx_p->cipher_mode) {
@@ -682,7 +684,6 @@ static void cc_cipher_complete(struct de

- cc_unmap_cipher_request(dev, req_ctx, ivsize, src, dst);

skcipher_request_complete(req, err);