[ovs-dev] [PATCH] datapath-windows: Add guards around IpHelper adapter binding calls

[Sairam Venugopal]

Protect internal adapter up/down calls with a dispatch lock. It was
observed that the InternalAdapter bind calls could happen out of order
thereby causing encap packets to not be sent properly.

Add assert around the IpHelper bind calls to ensure Up/Down gets called
only for the appropriate vports.

Signed-off-by: Sairam Venugopal <vsairam at vmware.com>
---
 datapath-windows/ovsext/Switch.h |  2 ++
 datapath-windows/ovsext/Vport.c  | 34 +++++++++++++++++++++++++++++++---
 2 files changed, 33 insertions(+), 3 deletions(-)

diff --git a/datapath-windows/ovsext/Switch.h b/datapath-windows/ovsext/Switch.h
index 18a9ec6..806ee78 100644
--- a/datapath-windows/ovsext/Switch.h
+++ b/datapath-windows/ovsext/Switch.h
@@ -131,6 +131,8 @@ typedef struct _OVS_SWITCH_CONTEXT
                                                      * vport */
     INT32                   countInternalVports;    /* the number of internal
                                                      * vports */
+    UINT32                  ipHelperBoundVportNo;   /* vportNo bound to
+                                                     * IpHelper */
 
     /*
      * 'portIdHashArray' ONLY contains ports that exist on the Hyper-V switch,
diff --git a/datapath-windows/ovsext/Vport.c b/datapath-windows/ovsext/Vport.c
index e8c4d7f..57e7510 100644
--- a/datapath-windows/ovsext/Vport.c
+++ b/datapath-windows/ovsext/Vport.c
@@ -100,6 +100,12 @@ static NTSTATUS GetNICAlias(PNDIS_SWITCH_NIC_PARAMETERS nicParam,
 static NTSTATUS OvsConvertIfCountedStrToAnsiStr(PIF_COUNTED_STRING wStr,
                                                 CHAR *str,
                                                 UINT16 maxStrLen);
+_Requires_lock_held_(switchContext->dispatchLock)
+static VOID OvsBindVportWithIpHelper(POVS_VPORT_ENTRY vport,
+                                     POVS_SWITCH_CONTEXT switchContext);
+_Requires_lock_held_(switchContext->dispatchLock)
+static VOID OvsUnBindVportWithIpHelper(POVS_VPORT_ENTRY vport,
+                                       POVS_SWITCH_CONTEXT switchContext);
 
 /*
  * --------------------------------------------------------------------------
@@ -453,7 +459,7 @@ HvConnectNic(POVS_SWITCH_CONTEXT switchContext,
     vport->nicState = NdisSwitchNicStateConnected;
 
     if (nicParam->NicType == NdisSwitchNicTypeInternal) {
-        OvsInternalAdapterUp(vport->portNo, &vport->netCfgInstanceId);
+        OvsBindVportWithIpHelper(vport, switchContext);
     }
 
     NdisReleaseRWLock(switchContext->dispatchLock, &lockState);
@@ -633,7 +639,7 @@ HvDisconnectNic(POVS_SWITCH_CONTEXT switchContext,
     }
 
     if (isInternalPort) {
-        OvsInternalAdapterDown(vport->portNo, vport->netCfgInstanceId);
+        OvsUnBindVportWithIpHelper(vport, switchContext);
         OvsRemoveAndDeleteVport(NULL, switchContext, vport, TRUE, TRUE);
         OvsPostVportEvent(&event);
     }
@@ -1308,7 +1314,7 @@ OvsRemoveAndDeleteVport(PVOID usrParamsContext,
         if (hvDelete && vport->isAbsentOnHv == FALSE) {
             switchContext->countInternalVports--;
             ASSERT(switchContext->countInternalVports >= 0);
-            OvsInternalAdapterDown(vport->portNo, vport->netCfgInstanceId);
+            OvsUnBindVportWithIpHelper(vport, switchContext);
         }
         hvSwitchPort = TRUE;
         break;
@@ -2814,3 +2820,25 @@ OvsTunnelVportPendingInit(PVOID context,
         ASSERT(*replyLen != 0);
     }
 }
+
+_Use_decl_annotations_
+static VOID
+OvsBindVportWithIpHelper(POVS_VPORT_ENTRY vport,
+                         POVS_SWITCH_CONTEXT switchContext)
+{
+    OVS_LOG_TRACE("OvsBindVportWithIpHelper: %d", vport->portNo);
+    ASSERT(switchContext->ipHelperBoundVportNo == 0);
+    switchContext->ipHelperBoundVportNo = vport->portNo;
+    OvsInternalAdapterUp(vport->portNo, &vport->netCfgInstanceId);
+}
+
+_Use_decl_annotations_
+static VOID
+OvsUnBindVportWithIpHelper(POVS_VPORT_ENTRY vport,
+                           POVS_SWITCH_CONTEXT switchContext)
+{
+    OVS_LOG_TRACE("OvsUnBindVportWithIpHelper: %d", vport->portNo);
+    ASSERT(switchContext->ipHelperBoundVportNo == vport->portNo);
+    switchContext->ipHelperBoundVportNo = 0;
+    OvsInternalAdapterDown(vport->portNo, vport->netCfgInstanceId);
+}
-- 
2.9.0.windows.1