diff --git a/drivers/nvme/target/zns.c b/drivers/nvme/target/zns.c
index 235553337fb2..1466698751c5 100644
--- a/drivers/nvme/target/zns.c
+++ b/drivers/nvme/target/zns.c
@@ -100,6 +100,7 @@ void nvmet_execute_identify_cns_cs_ns(struct nvmet_req *req)
 	struct nvme_id_ns_zns *id_zns;
 	u64 zsze;
 	u16 status;
+	u32 mar, mor;
 
 	if (le32_to_cpu(req->cmd->identify.nsid) == NVME_NSID_ALL) {
 		req->error_loc = offsetof(struct nvme_identify, nsid);
@@ -126,8 +127,20 @@ void nvmet_execute_identify_cns_cs_ns(struct nvmet_req *req)
 	zsze = (bdev_zone_sectors(req->ns->bdev) << 9) >>
 					req->ns->blksize_shift;
 	id_zns->lbafe[0].zsze = cpu_to_le64(zsze);
-	id_zns->mor = cpu_to_le32(bdev_max_open_zones(req->ns->bdev));
-	id_zns->mar = cpu_to_le32(bdev_max_active_zones(req->ns->bdev));
+
+	mor = bdev_max_open_zones(req->ns->bdev);
+	if (!mor)
+		mor = U32_MAX;
+	else
+		mor--;
+	id_zns->mor = cpu_to_le32(mor);
+
+	mar = bdev_max_active_zones(req->ns->bdev);
+	if (!mar)
+		mar = U32_MAX;
+	else
+		mar--;
+	id_zns->mar = cpu_to_le32(mar);
 
 done:
 	status = nvmet_copy_to_sgl(req, 0, id_zns, sizeof(*id_zns));