[PATCH] crypto: virtio - Less function calls in __virtio_crypto_akcipher_do_req() after error detection

[Markus Elfring]

From: Markus Elfring <elfr...@users.sourceforge.net>
Date: Sun, 24 Dec 2023 20:42:19 +0100

The kfree() function was called in up to two cases by the
__virtio_crypto_akcipher_do_req() function during error handling
even if the passed variable contained a null pointer.
This issue was detected by using the Coccinelle software.

* Adjust jump targets.

* Delete two initialisations which became unnecessary
  with this refactoring.

Signed-off-by: Markus Elfring <elfr...@users.sourceforge.net>
---
 drivers/crypto/virtio/virtio_crypto_akcipher_algs.c | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/drivers/crypto/virtio/virtio_crypto_akcipher_algs.c 
b/drivers/crypto/virtio/virtio_crypto_akcipher_algs.c
index 2621ff8a9376..15dbe67f0d31 100644
--- a/drivers/crypto/virtio/virtio_crypto_akcipher_algs.c
+++ b/drivers/crypto/virtio/virtio_crypto_akcipher_algs.c
@@ -224,11 +224,11 @@ static int __virtio_crypto_akcipher_do_req(struct 
virtio_crypto_akcipher_request
        struct virtio_crypto *vcrypto = ctx->vcrypto;
        struct virtio_crypto_op_data_req *req_data = vc_req->req_data;
        struct scatterlist *sgs[4], outhdr_sg, inhdr_sg, srcdata_sg, dstdata_sg;
-       void *src_buf = NULL, *dst_buf = NULL;
+       void *src_buf, *dst_buf = NULL;
        unsigned int num_out = 0, num_in = 0;
        int node = dev_to_node(&vcrypto->vdev->dev);
        unsigned long flags;
-       int ret = -ENOMEM;
+       int ret;
        bool verify = vc_akcipher_req->opcode == VIRTIO_CRYPTO_AKCIPHER_VERIFY;
        unsigned int src_len = verify ? req->src_len + req->dst_len : 
req->src_len;

@@ -239,7 +239,7 @@ static int __virtio_crypto_akcipher_do_req(struct 
virtio_crypto_akcipher_request
        /* src data */
        src_buf = kcalloc_node(src_len, 1, GFP_KERNEL, node);
        if (!src_buf)
-               goto err;
+               return -ENOMEM;

        if (verify) {
                /* for verify operation, both src and dst data work as OUT 
direction */
@@ -254,7 +254,7 @@ static int __virtio_crypto_akcipher_do_req(struct 
virtio_crypto_akcipher_request
                /* dst data */
                dst_buf = kcalloc_node(req->dst_len, 1, GFP_KERNEL, node);
                if (!dst_buf)
-                       goto err;
+                       goto free_src;

                sg_init_one(&dstdata_sg, dst_buf, req->dst_len);
                sgs[num_out + num_in++] = &dstdata_sg;
@@ -277,9 +277,9 @@ static int __virtio_crypto_akcipher_do_req(struct 
virtio_crypto_akcipher_request
        return 0;

 err:
-       kfree(src_buf);
        kfree(dst_buf);
-
+free_src;
+       kfree(src_buf);
        return -ENOMEM;
 }

--
2.43.0