hw/nvme: fix verification of select field in namespace attachment

[Naveen <naveen.n1@samsung.com>]

Fix is added to check for reserved value in select field for 
namespace attachment

Signed-off-by: Naveen Nagar <naveen.n1@samsung.com>
Signed-off-by: Klaus Jensen <k.jensen@samsung.com>
cc: Minwoo Im <minwoo.im.dev@gmail.com>

---
 hw/nvme/ctrl.c       | 13 +++++++++----
 include/block/nvme.h |  5 +++++
 2 files changed, 14 insertions(+), 4 deletions(-)

diff --git a/hw/nvme/ctrl.c b/hw/nvme/ctrl.c
index 6baf9e0..2c59c74 100644
--- a/hw/nvme/ctrl.c
+++ b/hw/nvme/ctrl.c
@@ -5191,7 +5191,7 @@ static uint16_t nvme_ns_attachment(NvmeCtrl *n, NvmeRequest *req)
     uint16_t list[NVME_CONTROLLER_LIST_SIZE] = {};
     uint32_t nsid = le32_to_cpu(req->cmd.nsid);
     uint32_t dw10 = le32_to_cpu(req->cmd.cdw10);
-    bool attach = !(dw10 & 0xf);
+    uint8_t sel = dw10 & 0xf;
     uint16_t *nr_ids = &list[0];
     uint16_t *ids = &list[1];
     uint16_t ret;
@@ -5224,7 +5224,8 @@ static uint16_t nvme_ns_attachment(NvmeCtrl *n, NvmeRequest *req)
             return NVME_NS_CTRL_LIST_INVALID | NVME_DNR;
         }
 
-        if (attach) {
+        switch (sel) {
+        case NVME_NS_ATTACHMENT_ATTACH:
             if (nvme_ns(ctrl, nsid)) {
                 return NVME_NS_ALREADY_ATTACHED | NVME_DNR;
             }
@@ -5235,7 +5236,8 @@ static uint16_t nvme_ns_attachment(NvmeCtrl *n, NvmeRequest *req)
 
             nvme_attach_ns(ctrl, ns);
             nvme_select_iocs_ns(ctrl, ns);
-        } else {
+            break;
+        case NVME_NS_ATTACHMENT_DETACH:
             if (!nvme_ns(ctrl, nsid)) {
                 return NVME_NS_NOT_ATTACHED | NVME_DNR;
             }
@@ -5244,8 +5246,11 @@ static uint16_t nvme_ns_attachment(NvmeCtrl *n, NvmeRequest *req)
             ns->attached--;
 
             nvme_update_dmrsl(ctrl);
+            break;
+        default:
+            return NVME_INVALID_FIELD | NVME_DNR;
         }
-
+        
         /*
          * Add namespace id to the changed namespace id list for event clearing
          * via Get Log Page command.
diff --git a/include/block/nvme.h b/include/block/nvme.h
index 77aae01..e3bd47b 100644
--- a/include/block/nvme.h
+++ b/include/block/nvme.h
@@ -1154,6 +1154,11 @@ enum NvmeIdCtrlCmic {
     NVME_CMIC_MULTI_CTRL    = 1 << 1,
 };
 
+enum NvmeNsAttachmentOperation {
+    NVME_NS_ATTACHMENT_ATTACH = 0x0,
+    NVME_NS_ATTACHMENT_DETACH = 0x1,
+};
+
 #define NVME_CTRL_SQES_MIN(sqes) ((sqes) & 0xf)
 #define NVME_CTRL_SQES_MAX(sqes) (((sqes) >> 4) & 0xf)
 #define NVME_CTRL_CQES_MIN(cqes) ((cqes) & 0xf)
-- 
1.8.3.1