2022-04-18 12:42:13

by zhenwei pi

[permalink] [raw]
Subject: [PATCH v2 3/4] virtio-crypto: adjust dst_len at ops callback

From: lei he <[email protected]>

For some akcipher operations(eg, decryption of pkcs1pad(rsa)),
the length of returned result maybe less than akcipher_req->dst_len,
we need to recalculate the actual dst_len through the virt-queue
protocol.

Signed-off-by: lei he <[email protected]>
Signed-off-by: zhenwei pi <[email protected]>
---
drivers/crypto/virtio/virtio_crypto_akcipher_algs.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/crypto/virtio/virtio_crypto_akcipher_algs.c b/drivers/crypto/virtio/virtio_crypto_akcipher_algs.c
index 9561bc2df62b..82db86e088c2 100644
--- a/drivers/crypto/virtio/virtio_crypto_akcipher_algs.c
+++ b/drivers/crypto/virtio/virtio_crypto_akcipher_algs.c
@@ -90,9 +90,12 @@ static void virtio_crypto_dataq_akcipher_callback(struct virtio_crypto_request *
}

akcipher_req = vc_akcipher_req->akcipher_req;
- if (vc_akcipher_req->opcode != VIRTIO_CRYPTO_AKCIPHER_VERIFY)
+ if (vc_akcipher_req->opcode != VIRTIO_CRYPTO_AKCIPHER_VERIFY) {
+ /* actuall length maybe less than dst buffer */
+ akcipher_req->dst_len = len - sizeof(vc_req->status);
sg_copy_from_buffer(akcipher_req->dst, sg_nents(akcipher_req->dst),
vc_akcipher_req->dst_buf, akcipher_req->dst_len);
+ }
virtio_crypto_akcipher_finalize_req(vc_akcipher_req, akcipher_req, error);
}

--
2.20.1