crypto: atmel-aes - Fix CTR counter overflow when multiple fragments
The CTR transfer works in fragments of data of maximum 1 MByte because
of the 16 bit CTR counter embedded in the IP. Fix the CTR counter
overflow handling for messages larger than 1 MByte.
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Fixes: 781a08d9740a ("crypto: atmel-aes - Fix counter overflow in CTR mode")
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
diff --git a/drivers/crypto/atmel-aes.c b/drivers/crypto/atmel-aes.c
index 245d45f..b001fdc 100644
--- a/drivers/crypto/atmel-aes.c
+++ b/drivers/crypto/atmel-aes.c
@@ -120,7 +120,7 @@ struct atmel_aes_ctr_ctx {
size_t offset;
struct scatterlist src[2];
struct scatterlist dst[2];
- u16 blocks;
+ u32 blocks;
};
struct atmel_aes_gcm_ctx {
@@ -527,6 +527,12 @@ static void atmel_aes_ctr_update_req_iv(struct atmel_aes_dev *dd)
unsigned int ivsize = crypto_skcipher_ivsize(skcipher);
int i;
+ /*
+ * The CTR transfer works in fragments of data of maximum 1 MByte
+ * because of the 16 bit CTR counter embedded in the IP. When reaching
+ * here, ctx->blocks contains the number of blocks of the last fragment
+ * processed, there is no need to explicit cast it to u16.
+ */
for (i = 0; i < ctx->blocks; i++)
crypto_inc((u8 *)ctx->iv, AES_BLOCK_SIZE);
