[PATCH] nvmet-auth: fix dhgroup negotiation

[Konrad Sztyber]

There were a couple of things wrong with dhgroup negotiation.  Firstly,
the condition comparing host's dhgroups against configured dhgroup was
inverted.  Secondly, once fallback dhgroup was selected, only dhg_id was
updated, without proper dhgroup setup (e.g. generating the key).

Signed-off-by: Konrad Sztyber <konrad.sztyber at intel.com>
---
 drivers/nvme/target/fabrics-cmd-auth.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/nvme/target/fabrics-cmd-auth.c b/drivers/nvme/target/fabrics-cmd-auth.c
index eb7785be0ca7..40038a6624ff 100644
--- a/drivers/nvme/target/fabrics-cmd-auth.c
+++ b/drivers/nvme/target/fabrics-cmd-auth.c
@@ -81,7 +81,7 @@ static u16 nvmet_auth_negotiate(struct nvmet_req *req, void *d)
 	for (i = 0; i < data->auth_protocol[0].dhchap.dhlen; i++) {
 		int tmp_dhgid = data->auth_protocol[0].dhchap.idlist[i + 30];
 
-		if (tmp_dhgid != ctrl->dh_gid) {
+		if (tmp_dhgid == ctrl->dh_gid) {
 			dhgid = tmp_dhgid;
 			break;
 		}
@@ -101,7 +101,9 @@ static u16 nvmet_auth_negotiate(struct nvmet_req *req, void *d)
 		pr_debug("%s: ctrl %d qid %d: configured DH group %s not found\n",
 			 __func__, ctrl->cntlid, req->sq->qid,
 			 nvme_auth_dhgroup_name(fallback_dhgid));
-		ctrl->dh_gid = fallback_dhgid;
+
+		if (nvmet_setup_dhgroup(ctrl, fallback_dhgid) < 0)
+			return NVME_AUTH_DHCHAP_FAILURE_DHGROUP_UNUSABLE;
 	}
 	pr_debug("%s: ctrl %d qid %d: selected DH group %s (%d)\n",
 		 __func__, ctrl->cntlid, req->sq->qid,
-- 
2.43.0