nvme-auth: auth success1 msg always includes resp

In cases where RVALID is false, the response is still transmitted,
but is cleared to zero.

Relevant extract from the spec:
Response R2, if valid (i.e., if the RVALID field is set to 01h),
cleared to 0h otherwise
Signed-off-by: Mark O'Donovan <shiftee@posteo.net>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Christoph Hellwig <hch@lst.de>

drivers/nvme/host/auth.c

@@ -339,10 +339,7 @@ static int nvme_auth_process_dhchap_success1(struct nvme_ctrl *ctrl,
 		struct nvme_dhchap_queue_context *chap)
 {
 	struct nvmf_auth_dhchap_success1_data *data = chap->buf;
-	size_t size = sizeof(*data);
-
-	if (chap->s2)
-		size += chap->hash_len;
+	size_t size = sizeof(*data) + chap->hash_len;
 
 	if (size > CHAP_BUF_SIZE) {
 		chap->status = NVME_AUTH_DHCHAP_FAILURE_INCORRECT_PAYLOAD;

include/linux/nvme.h

@@ -1732,7 +1732,7 @@ struct nvmf_auth_dhchap_success1_data {
 	__u8		rsvd2;
 	__u8		rvalid;
 	__u8		rsvd3[7];
-	/* 'hl' bytes of response value if 'rvalid' is set */
+	/* 'hl' bytes of response value */
 	__u8		rval[];
 };