Re: [PATCH 3/6] libnvdimm/security: Drop direct dependency on key_type_encrypted

[Dave Jiang]

On 3/18/19 11:06 PM, Dan Williams wrote:
> Lookup the key type by name and protect libnvdimm from encrypted_keys.ko
> module load failures.
> 
> Cc: Vishal Verma <vishal.l.verma@xxxxxxxxx>
> Cc: Dave Jiang <dave.jiang@xxxxxxxxx>
> Cc: Keith Busch <keith.busch@xxxxxxxxx>
> Cc: Ira Weiny <ira.weiny@xxxxxxxxx>
> Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx>

Reviewed-by: Dave Jiang <dave.jiang@xxxxxxxxx>

> ---
>  drivers/nvdimm/security.c |   11 +++++++++--
>  1 file changed, 9 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/nvdimm/security.c b/drivers/nvdimm/security.c
> index f8bb746a549f..7f9e412f743a 100644
> --- a/drivers/nvdimm/security.c
> +++ b/drivers/nvdimm/security.c
> @@ -48,12 +48,17 @@ static void nvdimm_put_key(struct key *key)
>  static struct key *nvdimm_request_key(struct nvdimm *nvdimm)
>  {
>  	struct key *key = NULL;
> +	struct key_type *type;
>  	static const char NVDIMM_PREFIX[] = "nvdimm:";
>  	char desc[NVDIMM_KEY_DESC_LEN + sizeof(NVDIMM_PREFIX)];
>  	struct device *dev = &nvdimm->dev;
>  
>  	sprintf(desc, "%s%s", NVDIMM_PREFIX, nvdimm->dimm_id);
> -	key = request_key(&key_type_encrypted, desc, "");
> +	type = key_type_lookup("encrypted");
> +	if (IS_ERR(type))
> +		return (struct key *) type;
> +
> +	key = request_key(type, desc, "");
>  	if (IS_ERR(key)) {
>  		if (PTR_ERR(key) == -ENOKEY)
>  			dev_dbg(dev, "request_key() found no key\n");
> @@ -88,7 +93,7 @@ static struct key *nvdimm_lookup_user_key(struct nvdimm *nvdimm,
>  		return NULL;
>  
>  	key = key_ref_to_ptr(keyref);
> -	if (key->type != &key_type_encrypted) {
> +	if (strcmp(key->type->name, "encrypted") != 0) {
>  		key_put(key);
>  		return NULL;
>  	}
> @@ -452,3 +457,5 @@ void nvdimm_security_overwrite_query(struct work_struct *work)
>  	__nvdimm_security_overwrite_query(nvdimm);
>  	nvdimm_bus_unlock(&nvdimm->dev);
>  }
> +
> +MODULE_SOFTDEP("pre: encrypted_keys");
>