[PATCH] nvmet: clean up DH group state on initialization failure

[PATCH] nvmet: clean up DH group state on initialization failure

[Sreeraj S Kurup]

nvmet_setup_dhgroup() leaves the DH transform and group ID
initialized when private-key generation, public-key allocation,
or public-key generation fails.

A subsequent invocation with the same DH group incorrectly
returns success because the existing transform and group ID
are treated as proof of successful initialization.

Release the transform and reset the group state on initialization
failures so that subsequent attempts can properly retry setup.

Signed-off-by: Sreeraj S Kurup <sreekuttan2156239@gmail.com>
---
 drivers/nvme/target/auth.c | 14 +++++++++++++-
 1 file changed, 13 insertions(+), 1 deletion(-)

diff --git a/drivers/nvme/target/auth.c b/drivers/nvme/target/auth.c
index ccba84b1344e..7733d50de708 100644
--- a/drivers/nvme/target/auth.c
+++ b/drivers/nvme/target/auth.c
@@ -105,6 +105,10 @@ int nvmet_setup_dhgroup(struct nvmet_ctrl *ctrl, u8 dhgroup_id)
 		if (ret < 0) {
 			pr_debug("%s: ctrl %d failed to generate private key, err %d\n",
 				 __func__, ctrl->cntlid, ret);
+			crypto_free_kpp(ctrl->dh_tfm);
+			ctrl->dh_tfm = NULL;
+			ctrl->dh_gid = 0;
+			ctrl->dh_keysize = 0;
 			kfree_sensitive(ctrl->dh_key);
 			ctrl->dh_key = NULL;
 			return ret;
@@ -115,6 +119,10 @@ int nvmet_setup_dhgroup(struct nvmet_ctrl *ctrl, u8 dhgroup_id)
 		if (!ctrl->dh_key) {
 			pr_warn("ctrl %d failed to allocate public key\n",
 				ctrl->cntlid);
+			crypto_free_kpp(ctrl->dh_tfm);
+			ctrl->dh_tfm = NULL;
+			ctrl->dh_gid = 0;
+			ctrl->dh_keysize = 0;
 			return -ENOMEM;
 		}
 		ret = nvme_auth_gen_pubkey(ctrl->dh_tfm, ctrl->dh_key,
@@ -122,8 +130,12 @@ int nvmet_setup_dhgroup(struct nvmet_ctrl *ctrl, u8 dhgroup_id)
 		if (ret < 0) {
 			pr_warn("ctrl %d failed to generate public key\n",
 				ctrl->cntlid);
-			kfree(ctrl->dh_key);
+			kfree_sensitive(ctrl->dh_key);
 			ctrl->dh_key = NULL;
+			crypto_free_kpp(ctrl->dh_tfm);
+			ctrl->dh_tfm = NULL;
+			ctrl->dh_gid = 0;
+			ctrl->dh_keysize = 0;
 		}
 	}
 
-- 
2.55.0

Re: [PATCH] nvmet: clean up DH group state on initialization failure

[Hannes Reinecke]

On 11/10/26 9:48 AM, Sreeraj S Kurup wrote:
> nvmet_setup_dhgroup() leaves the DH transform and group ID
> initialized when private-key generation, public-key allocation,
> or public-key generation fails.
> 
> A subsequent invocation with the same DH group incorrectly
> returns success because the existing transform and group ID
> are treated as proof of successful initialization.
> 
> Release the transform and reset the group state on initialization
> failures so that subsequent attempts can properly retry setup.
> 
> Signed-off-by: Sreeraj S Kurup <sreekuttan2156239@gmail.com>
> ---
>   drivers/nvme/target/auth.c | 14 +++++++++++++-
>   1 file changed, 13 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/nvme/target/auth.c b/drivers/nvme/target/auth.c
> index ccba84b1344e..7733d50de708 100644
> --- a/drivers/nvme/target/auth.c
> +++ b/drivers/nvme/target/auth.c
> @@ -105,6 +105,10 @@ int nvmet_setup_dhgroup(struct nvmet_ctrl *ctrl, u8 dhgroup_id)
>   		if (ret < 0) {
>   			pr_debug("%s: ctrl %d failed to generate private key, err %d\n",
>   				 __func__, ctrl->cntlid, ret);
> +			crypto_free_kpp(ctrl->dh_tfm);
> +			ctrl->dh_tfm = NULL;
> +			ctrl->dh_gid = 0;
> +			ctrl->dh_keysize = 0;
>   			kfree_sensitive(ctrl->dh_key);
>   			ctrl->dh_key = NULL;
>   			return ret;
> @@ -115,6 +119,10 @@ int nvmet_setup_dhgroup(struct nvmet_ctrl *ctrl, u8 dhgroup_id)
>   		if (!ctrl->dh_key) {
>   			pr_warn("ctrl %d failed to allocate public key\n",
>   				ctrl->cntlid);
> +			crypto_free_kpp(ctrl->dh_tfm);
> +			ctrl->dh_tfm = NULL;
> +			ctrl->dh_gid = 0;
> +			ctrl->dh_keysize = 0;
>   			return -ENOMEM;
>   		}
>   		ret = nvme_auth_gen_pubkey(ctrl->dh_tfm, ctrl->dh_key,
> @@ -122,8 +130,12 @@ int nvmet_setup_dhgroup(struct nvmet_ctrl *ctrl, u8 dhgroup_id)
>   		if (ret < 0) {
>   			pr_warn("ctrl %d failed to generate public key\n",
>   				ctrl->cntlid);
> -			kfree(ctrl->dh_key);
> +			kfree_sensitive(ctrl->dh_key);
>   			ctrl->dh_key = NULL;
> +			crypto_free_kpp(ctrl->dh_tfm);
> +			ctrl->dh_tfm = NULL;
> +			ctrl->dh_gid = 0;
> +			ctrl->dh_keysize = 0;
>   		}
>   	}
>   

Can't we make this a helper?

Cheers,

Hannes
-- 
Dr. Hannes Reinecke                  Kernel Storage Architect
hare@suse.de                                +49 911 74053 688
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