From bfb151c8123c8a28bd3964b08234040f63e4dafe Mon Sep 17 00:00:00 2001
From: Tamilmani Manoharan <tamanoha@microsoft.com>
Date: Wed, 18 Oct 2017 14:33:48 -0700
Subject: [PATCH 1/3] Fix for leaking CA while deleting network. Even if
 deleting endpoint failed, CNI should invoke ipam release call.

---
 cni/network/network.go | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/cni/network/network.go b/cni/network/network.go
index 2e51726c06..dc1314b50b 100644
--- a/cni/network/network.go
+++ b/cni/network/network.go
@@ -320,8 +320,8 @@ func (plugin *netPlugin) Delete(args *cniSkel.CmdArgs) error {
 	// Delete the endpoint.
 	err = plugin.nm.DeleteEndpoint(networkId, endpointId)
 	if err != nil {
-		err = plugin.Errorf("Failed to delete endpoint: %v", err)
-		return err
+		// Log the error but don't return before releasing address
+		log.Printf("Container Namespace might have been removed. Failed to delete endpoint: %v", err)
 	}
 
 	// Call into IPAM plugin to release the endpoint's addresses.
@@ -330,8 +330,7 @@ func (plugin *netPlugin) Delete(args *cniSkel.CmdArgs) error {
 		nwCfg.Ipam.Address = address.IP.String()
 		err = plugin.DelegateDel(nwCfg.Ipam.Type, nwCfg)
 		if err != nil {
-			err = plugin.Errorf("Failed to release address: %v", err)
-			return err
+			log.Printf("Failed to release address: %v", err)
 		}
 	}
 

From 3c5ae5da8c3362b152db46d81dd66e8a049164d3 Mon Sep 17 00:00:00 2001
From: Tamilmani Manoharan <tamanoha@microsoft.com>
Date: Wed, 18 Oct 2017 14:59:21 -0700
Subject: [PATCH 2/3] Handled address not found during release address as false
 positive

---
 cni/network/network.go | 3 ++-
 ipam/pool.go           | 8 ++++----
 2 files changed, 6 insertions(+), 5 deletions(-)

diff --git a/cni/network/network.go b/cni/network/network.go
index dc1314b50b..458dbd17ab 100644
--- a/cni/network/network.go
+++ b/cni/network/network.go
@@ -330,7 +330,8 @@ func (plugin *netPlugin) Delete(args *cniSkel.CmdArgs) error {
 		nwCfg.Ipam.Address = address.IP.String()
 		err = plugin.DelegateDel(nwCfg.Ipam.Type, nwCfg)
 		if err != nil {
-			log.Printf("Failed to release address: %v", err)
+			plugin.Errorf("Failed to release address: %v", err)
+			return err
 		}
 	}
 
diff --git a/ipam/pool.go b/ipam/pool.go
index 657142ce23..f61d3ee440 100644
--- a/ipam/pool.go
+++ b/ipam/pool.go
@@ -542,13 +542,13 @@ func (ap *addressPool) releaseAddress(address string, options map[string]string)
 
 	// Fail if an address record with a matching ID is not found.
 	if ar == nil || (id != "" && id != ar.ID) {
-		err = errAddressNotFound
-		return err
+		log.Printf("Address not found. Not Returning error")
+		return nil
 	}
 
 	if !ar.InUse {
-		err = errAddressNotInUse
-		return err
+		log.Printf("Address not in use. Not Returning error")
+		return nil
 	}
 
 	if ar.ID != "" {

From 5ba70f9092facbfe12e8e745666b6e4903e39b75 Mon Sep 17 00:00:00 2001
From: Tamilmani Manoharan <tamanoha@microsoft.com>
Date: Wed, 18 Oct 2017 17:15:53 -0700
Subject: [PATCH 3/3] Made changes in netlink code to ignore interface not
 found error

---
 cni/network/network.go |  6 +++---
 netlink/link.go        | 11 +++++++----
 network/endpoint.go    |  3 ++-
 3 files changed, 12 insertions(+), 8 deletions(-)

diff --git a/cni/network/network.go b/cni/network/network.go
index 458dbd17ab..2e51726c06 100644
--- a/cni/network/network.go
+++ b/cni/network/network.go
@@ -320,8 +320,8 @@ func (plugin *netPlugin) Delete(args *cniSkel.CmdArgs) error {
 	// Delete the endpoint.
 	err = plugin.nm.DeleteEndpoint(networkId, endpointId)
 	if err != nil {
-		// Log the error but don't return before releasing address
-		log.Printf("Container Namespace might have been removed. Failed to delete endpoint: %v", err)
+		err = plugin.Errorf("Failed to delete endpoint: %v", err)
+		return err
 	}
 
 	// Call into IPAM plugin to release the endpoint's addresses.
@@ -330,7 +330,7 @@ func (plugin *netPlugin) Delete(args *cniSkel.CmdArgs) error {
 		nwCfg.Ipam.Address = address.IP.String()
 		err = plugin.DelegateDel(nwCfg.Ipam.Type, nwCfg)
 		if err != nil {
-			plugin.Errorf("Failed to release address: %v", err)
+			err = plugin.Errorf("Failed to release address: %v", err)
 			return err
 		}
 	}
diff --git a/netlink/link.go b/netlink/link.go
index 3021727bc8..7bf3ec893e 100644
--- a/netlink/link.go
+++ b/netlink/link.go
@@ -7,6 +7,7 @@ import (
 	"fmt"
 	"net"
 
+	"github.com/Azure/azure-container-networking/log"
 	"golang.org/x/sys/unix"
 )
 
@@ -146,15 +147,17 @@ func AddLink(link Link) error {
 // DeleteLink deletes a network interface.
 func DeleteLink(name string) error {
 	if name == "" {
-		return fmt.Errorf("Invalid link name")
+		log.Printf("[net] Invalid link name. Not returning error")
+		return nil
 	}
 
-	s, err := getSocket()
+	iface, err := net.InterfaceByName(name)
 	if err != nil {
-		return err
+		log.Printf("[net] Interface not found. Not returning error")
+		return nil
 	}
 
-	iface, err := net.InterfaceByName(name)
+	s, err := getSocket()
 	if err != nil {
 		return err
 	}
diff --git a/network/endpoint.go b/network/endpoint.go
index 07ac9eb7ee..7b2e743860 100644
--- a/network/endpoint.go
+++ b/network/endpoint.go
@@ -83,7 +83,8 @@ func (nw *network) deleteEndpoint(endpointId string) error {
 	// Look up the endpoint.
 	ep, err := nw.getEndpoint(endpointId)
 	if err != nil {
-		return err
+		log.Printf("[net] Endpoint %v not found. Not Returning error", endpointId)
+		return nil
 	}
 
 	// Call the platform implementation.