[FAB-7470] Fix peer chaincode upgrade SIGSEGV panic

Before this change ugrading the chaincode following the Reconfigure
your network tutorial fails with a panic:

panic: runtime error: invalid memory address or nil pointer dereference
[signal SIGSEGV: segmentation violation code=0x1 addr=0x20 pc=0xbb36bb]

goroutine 1 [running]:
github.com/hyperledger/fabric/peer/chaincode.chaincodeUpgrade(0x0, 0xc420
3c4720, 0x0, 0x0)
	/opt/gopath/src/github.com/hyperledger/fabric/peer/chaincode/upgr
ade.go:141 +0x4b
[...]
main.main()
	/opt/gopath/src/github.com/hyperledger/fabric/peer/main.go:112 +0
x493

After this change, the command succeeds as expected. This CR adds a
related test to cover the issue.

$ go test -v -run TestUpgradeCmdWithNilCF github.com/hyperledger/fabric/p
eer/chaincode
=== RUN   TestUpgradeCmdWithNilCF
--- FAIL: TestUpgradeCmdWithNilCF (0.02s)
        Error Trace:    upgrade_test.go:86
			asm_amd64.s:509
			panic.go:491
			panic.go:63
			signal_unix.go:367
			upgrade.go:135
			upgrade.go:43
			command.go:599
			command.go:689
			command.go:648
			upgrade_test.go:98
	Error:		Received unexpected error "runtime error: invalid
 memory address or nil pointer dereference"
	Messages:	'peer chaincode upgrade' command should have fail
ed without a panic

FAIL
exit status 1
FAIL	github.com/hyperledger/fabric/peer/chaincode	0.042s

$ go test -v -run TestUpgradeCmdWithNilCF github.com/hyperledger/fabric/p
eer/chaincode
=== RUN   TestUpgradeCmdWithNilCF
Error: Error getting endorser client chaincode: error trying to connect t
o local peer: context deadline exceeded
Usage:
  upgrade [flags]
[...]
--- PASS: TestUpgradeCmdWithNilCF (3.03s)
PASS
ok  	github.com/hyperledger/fabric/peer/chaincode	3.045s

Before CR:
$ go test -cover github.com/hyperledger/fabric/peer/chaincode
ok  	github.com/hyperledger/fabric/peer/chaincode	0.559s
	coverage: 81.3% of statements

After CR:
$ go test -cover github.com/hyperledger/fabric/peer/chaincode
ok  	github.com/hyperledger/fabric/peer/chaincode	3.611s
	coverage: 81.8% of statements

Change-Id: I65a7846c77481ff7dcddb410aebe74b8d6eb005c
Signed-off-by: Arnaud J Le Hors <lehors@us.ibm.com>

peer/chaincode/upgrade.go

@@ -40,14 +40,15 @@ func upgradeCmd(cf *ChaincodeCmdFactory) *cobra.Command {
 		ValidArgs: []string{"1"},
 		RunE: func(cmd *cobra.Command, args []string) error {
 			cf1 := cf
-			return chaincodeUpgrade(cf1, func() error {
+			if cf1 == nil {
 				var err error
-				if cf1 == nil {
-					cf1, err = InitCmdFactory(true, true)
-					if err != nil {
-						return err
-					}
+				cf1, err = InitCmdFactory(true, true)
+				if err != nil {
+					return err
 				}
+			}
+			return chaincodeUpgrade(cf1, func() error {
+				var err error
 				env, err := upgrade(cmd, cf1)
 				if err != nil {
 					return err

peer/chaincode/upgrade_test.go

@@ -140,3 +140,27 @@ func TestUpgradeCmdSendTXFail(t *testing.T) {
 		}
 	}
 }
+
+func TestUpgradeCmdWithNilCF(t *testing.T) {
+
+	// trap possible SIGSEV panic
+	defer func() {
+		var err error = nil
+		if r := recover(); r != nil {
+			err = fmt.Errorf("%v", r)
+		}
+		assert.NoError(t, err, "'peer chaincode upgrade' command should have failed without a panic")
+	}()
+
+	channelID = ""
+	InitMSP()
+
+	cmd := upgradeCmd(nil)
+	addFlags(cmd)
+
+	args := []string{"-C", "mychannel", "-n", "example02", "-p", "github.com/hyperledger/fabric/examples/chaincode/go/chaincode_example02",
+		"-v", "anotherversion", "-c", "{\"Function\":\"init\",\"Args\": [\"param\",\"1\"]}"}
+	cmd.SetArgs(args)
+	err := cmd.Execute()
+	assert.Error(t, err, "'peer chaincode upgrade' command should have failed without a panic")
+}