Hi,
On Tue, Dec 26, 2023 at 11:12:23AM +0100, Markus Elfring wrote:
> From: Markus Elfring <elfring@xxxxxxxxxxxxxxxxxxxxx>
> Date: Tue, 26 Dec 2023 11:00:20 +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.
If the script is short and simple would you mind, in the future,
including it below the fold -- this may help others do similar work down
the line -- Or you could also link to a git-managed version like what
Kees has been doing with his __counted_by patches [1].
>
> * Adjust jump targets.
>
> * Delete two initialisations which became unnecessary
> with this refactoring.
>
> Signed-off-by: Markus Elfring <elfring@xxxxxxxxxxxxxxxxxxxxx>
> ---
Nonetheless,
Reviewed-by: Justin Stitt <justinstitt@xxxxxxxxxx>
>
> v2:
> A typo was fixed for the delimiter of a label.
>
> 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..057da5bd8d30 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
>
[1]: https://lore.kernel.org/all/20230922175023.work.239-kees@xxxxxxxxxx/
Thanks
Justin
