From c39eb3bacdeb5c8e349fc45b772ed96fb1892e80 Mon Sep 17 00:00:00 2001
From: Harshavardhana <harsha@minio.io>
Date: Sun, 30 Jan 2022 12:55:21 -0800
Subject: [PATCH] fix: possible crash if private.key is empty (#14208)

Before
```
panic: runtime error: invalid memory address or nil pointer dereference
[signal SIGSEGV: segmentation violation code=0x1 addr=0x10 pc=0x9f54f7]

goroutine 1 [running]:
crypto/x509.IsEncryptedPEMBlock(...)
	crypto/x509/pem_decrypt.go:105
github.com/minio/minio/internal/config.LoadX509KeyPair({0xc00061e270, 0x0}, {0xc00061e2d0, 0x25})
	github.com/minio/minio/internal/config/certs.go:88 +0xf7
github.com/minio/pkg/certs.(*Manager).AddCertificate(0xc000576150, {0xc00061e270, 0x25}, {0xc00061e2d0, 0x25})
	github.com/minio/pkg@v1.1.15/certs/certs.go:132 +0x368
github.com/minio/pkg/certs.NewManager({0x51f5910, 0xc00053e140}, {0xc00061e270, 0xc000580400}, {0xc00061e2d0, 0x25}, 0x4dc5880)
	github.com/minio/pkg@v1.1.15/certs/certs.go:97 +0x170
github.com/minio/minio/cmd.getTLSConfig()
```

After
```
ERROR Unable to load the TLS configuration: The private key is not readable
      > Please check your certificate
```
---
 internal/config/certs.go      |  3 +++
 internal/config/certs_test.go | 26 ++++++++++++++++++++++++++
 2 files changed, 29 insertions(+)

diff --git a/internal/config/certs.go b/internal/config/certs.go
index b80946c3c..713b19111 100644
--- a/internal/config/certs.go
+++ b/internal/config/certs.go
@@ -85,6 +85,9 @@ func LoadX509KeyPair(certFile, keyFile string) (tls.Certificate, error) {
 	if len(rest) > 0 {
 		return tls.Certificate{}, ErrSSLUnexpectedData(nil).Msg("The private key contains additional data")
 	}
+	if key == nil {
+		return tls.Certificate{}, ErrSSLUnexpectedData(nil).Msg("The private key is not readable")
+	}
 	if x509.IsEncryptedPEMBlock(key) {
 		password := env.Get(EnvCertPassword, "")
 		if len(password) == 0 {
diff --git a/internal/config/certs_test.go b/internal/config/certs_test.go
index 036adfd81..43f08100b 100644
--- a/internal/config/certs_test.go
+++ b/internal/config/certs_test.go
@@ -213,6 +213,32 @@ var loadX509KeyPairTests = []struct {
 	privateKey, certificate string
 	shouldFail              bool
 }{
+	{
+		password:   "",
+		privateKey: "",
+		certificate: `-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----`,
+		shouldFail: true,
+	},
 	{
 		password: "foobar",
 		privateKey: `-----BEGIN RSA PRIVATE KEY-----