From 88fea707a2889bd7305dae5308e19beb6b543436 Mon Sep 17 00:00:00 2001
From: Pascal Vizeli <pvizeli@syshack.ch>
Date: Mon, 19 Sep 2022 12:27:11 +0000
Subject: [PATCH 1/2] Add atomic writes

---
 go.mod                   |  3 ++-
 go.sum                   |  2 ++
 utils/bootfile/editor.go | 39 ++++++++++++++-------------------------
 3 files changed, 18 insertions(+), 26 deletions(-)

diff --git a/go.mod b/go.mod
index 2e6c6b9..a19d36b 100644
--- a/go.mod
+++ b/go.mod
@@ -8,6 +8,7 @@ require (
 	github.com/fntlnz/mountinfo v0.0.0-20171106231217-40cb42681fad
 	github.com/getsentry/sentry-go v0.13.0
 	github.com/godbus/dbus/v5 v5.1.0
-	github.com/pkg/errors v0.9.1 // indirect
+	github.com/natefinch/atomic v1.0.1
 	github.com/opencontainers/runtime-spec v1.0.2
+	github.com/pkg/errors v0.9.1 // indirect
 )
diff --git a/go.sum b/go.sum
index cbef9a4..9df88cf 100644
--- a/go.sum
+++ b/go.sum
@@ -99,6 +99,8 @@ github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd/go.mod h1:6dJ
 github.com/modern-go/reflect2 v0.0.0-20180701023420-4b7aa43c6742/go.mod h1:bx2lNnkwVCuqBIxFjflWJWanXIb3RllmbCylyMrvgv0=
 github.com/modern-go/reflect2 v1.0.1/go.mod h1:bx2lNnkwVCuqBIxFjflWJWanXIb3RllmbCylyMrvgv0=
 github.com/moul/http2curl v1.0.0/go.mod h1:8UbvGypXm98wA/IqH45anm5Y2Z6ep6O31QGOAZ3H0fQ=
+github.com/natefinch/atomic v1.0.1 h1:ZPYKxkqQOx3KZ+RsbnP/YsgvxWQPGxjC0oBt2AhwV0A=
+github.com/natefinch/atomic v1.0.1/go.mod h1:N/D/ELrljoqDyT3rZrsUmtsuzvHkeB/wWjHV22AZRbM=
 github.com/nats-io/jwt v0.3.0/go.mod h1:fRYCDE99xlTsqUzISS1Bi75UBJ6ljOJQOAAu5VglpSg=
 github.com/nats-io/nats.go v1.9.1/go.mod h1:ZjDU1L/7fJ09jvUSRVBR2e7+RnLiiIQyqyzEE/Zbp4w=
 github.com/nats-io/nkeys v0.1.0/go.mod h1:xpnFELMwJABBLVhffcfd1MZx6VsNRFpEugbxziKVo7w=
diff --git a/utils/bootfile/editor.go b/utils/bootfile/editor.go
index eaa109f..a21007e 100644
--- a/utils/bootfile/editor.go
+++ b/utils/bootfile/editor.go
@@ -6,6 +6,8 @@ import (
 	"strings"
 
 	logging "github.com/home-assistant/os-agent/utils/log"
+
+	"github.com/natefinch/atomic"
 )
 
 type Editor struct {
@@ -43,6 +45,7 @@ func (e Editor) DisableOption(optionName string) error {
 		logging.Error.Printf("Failed to open boot file %s: %s", e.FilePath, err)
 		return err
 	}
+	defer file.Close()
 
 	// Scan over all lines
 	fileScanner := bufio.NewScanner(file)
@@ -57,23 +60,9 @@ func (e Editor) DisableOption(optionName string) error {
 			outLines = append(outLines, line)
 		}
 	}
-	file.Close()
 
 	// Write all lines back to boot config file
-	file, err = os.Create(e.FilePath)
-	if err != nil {
-		logging.Error.Printf("Failed to write boot file %s: %s", e.FilePath, err)
-		return err
-	}
-
-	writter := bufio.NewWriter(file)
-	for _, line := range outLines {
-		writter.WriteString(line + "\n")
-	}
-	writter.Flush()
-	file.Close()
-
-	return nil
+	return e.writeNewBootFile(outLines)
 }
 
 func (e Editor) SetOption(optionName string, value string) error {
@@ -83,6 +72,7 @@ func (e Editor) SetOption(optionName string, value string) error {
 		logging.Error.Printf("Failed to open boot file %s: %s", e.FilePath, err)
 		return err
 	}
+	defer file.Close()
 
 	// Scan over all lines
 	fileScanner := bufio.NewScanner(file)
@@ -101,7 +91,6 @@ func (e Editor) SetOption(optionName string, value string) error {
 			outLines = append(outLines, line)
 		}
 	}
-	file.Close()
 
 	// No option found, add it
 	if !found {
@@ -109,18 +98,18 @@ func (e Editor) SetOption(optionName string, value string) error {
 	}
 
 	// Write all lines back to boot config file
-	file, err = os.Create(e.FilePath)
+	return e.writeNewBootFile(outLines)
+}
+
+func (e Editor) writeNewBootFile(lines []string) error {
+	// Write all lines back to boot config file
+	reader := strings.NewReader(strings.Join(lines, "\n"))
+
+	err := atomic.WriteFile(e.FilePath, reader)
 	if err != nil {
 		logging.Error.Printf("Failed to write boot file %s: %s", e.FilePath, err)
 		return err
 	}
 
-	writter := bufio.NewWriter(file)
-	for _, line := range outLines {
-		writter.WriteString(line + "\n")
-	}
-	writter.Flush()
-	file.Close()
-
-	return nil
+	return err
 }

From f7e6a365fc03464fe0ed8074127d3bf1faa7585b Mon Sep 17 00:00:00 2001
From: Pascal Vizeli <pvizeli@syshack.ch>
Date: Mon, 19 Sep 2022 12:33:45 +0000
Subject: [PATCH 2/2] close explicit before we going into write function

---
 utils/bootfile/editor.go | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/utils/bootfile/editor.go b/utils/bootfile/editor.go
index a21007e..51f2053 100644
--- a/utils/bootfile/editor.go
+++ b/utils/bootfile/editor.go
@@ -45,7 +45,6 @@ func (e Editor) DisableOption(optionName string) error {
 		logging.Error.Printf("Failed to open boot file %s: %s", e.FilePath, err)
 		return err
 	}
-	defer file.Close()
 
 	// Scan over all lines
 	fileScanner := bufio.NewScanner(file)
@@ -60,6 +59,7 @@ func (e Editor) DisableOption(optionName string) error {
 			outLines = append(outLines, line)
 		}
 	}
+	file.Close()
 
 	// Write all lines back to boot config file
 	return e.writeNewBootFile(outLines)
@@ -72,7 +72,6 @@ func (e Editor) SetOption(optionName string, value string) error {
 		logging.Error.Printf("Failed to open boot file %s: %s", e.FilePath, err)
 		return err
 	}
-	defer file.Close()
 
 	// Scan over all lines
 	fileScanner := bufio.NewScanner(file)
@@ -91,6 +90,7 @@ func (e Editor) SetOption(optionName string, value string) error {
 			outLines = append(outLines, line)
 		}
 	}
+	file.Close()
 
 	// No option found, add it
 	if !found {