From 3907ccfaec5d9965e306729936fc732c94d2c1e7 Mon Sep 17 00:00:00 2001 From: Tudor Ambarus Date: Fri, 13 Dec 2019 14:45:44 +0000 Subject: [PATCH] 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 Fixes: 781a08d9740a ("crypto: atmel-aes - Fix counter overflow in CTR mode") Signed-off-by: Tudor Ambarus Signed-off-by: Herbert Xu --- drivers/crypto/atmel-aes.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) 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); -- 2.7.4