From fdcd46d55b2e691a1ab3fd27fe27604b1972c3f2 Mon Sep 17 00:00:00 2001
From: steadytao <mail@steadytao.com>
Date: Fri, 3 Apr 2026 10:12:00 +1000
Subject: [PATCH] logging: add regression coverage for rotated file mode

---
 go.mod                             |  2 +-
 go.sum                             |  4 +--
 modules/logging/filewriter_test.go | 41 ++++++++++++++++++++++++++++++
 3 files changed, 44 insertions(+), 3 deletions(-)

diff --git a/go.mod b/go.mod
index 69a754dba..7b58bd410 100644
--- a/go.mod
+++ b/go.mod
@@ -4,7 +4,7 @@ go 1.25.0
 
 require (
 	github.com/BurntSushi/toml v1.6.0
-	github.com/DeRuina/timberjack v1.4.0
+	github.com/DeRuina/timberjack v1.4.1
 	github.com/KimMachineGun/automemlimit v0.7.5
 	github.com/Masterminds/sprig/v3 v3.3.0
 	github.com/alecthomas/chroma/v2 v2.23.1
diff --git a/go.sum b/go.sum
index da3692ec3..f8ae0e07e 100644
--- a/go.sum
+++ b/go.sum
@@ -28,8 +28,8 @@ github.com/BurntSushi/toml v0.3.1/go.mod h1:xHWCNGjB5oqiDr8zfno3MHue2Ht5sIBksp03
 github.com/BurntSushi/toml v1.5.0/go.mod h1:ukJfTF/6rtPPRCnwkur4qwRxa8vTRFBF0uk2lLoLwho=
 github.com/BurntSushi/toml v1.6.0 h1:dRaEfpa2VI55EwlIW72hMRHdWouJeRF7TPYhI+AUQjk=
 github.com/BurntSushi/toml v1.6.0/go.mod h1:ukJfTF/6rtPPRCnwkur4qwRxa8vTRFBF0uk2lLoLwho=
-github.com/DeRuina/timberjack v1.4.0 h1:Ipw9KjS/6K6A9D1xdhWebYJFqdQez5gXwfzmeKOroqE=
-github.com/DeRuina/timberjack v1.4.0/go.mod h1:RLoeQrwrCGIEF8gO5nV5b/gMD0QIy7bzQhBUgpp1EqE=
+github.com/DeRuina/timberjack v1.4.1 h1:JftM5HN/ITKehAXjtdbGqN5XZIS1biHm7VSjU0Qbtqg=
+github.com/DeRuina/timberjack v1.4.1/go.mod h1:RLoeQrwrCGIEF8gO5nV5b/gMD0QIy7bzQhBUgpp1EqE=
 github.com/KimMachineGun/automemlimit v0.7.5 h1:RkbaC0MwhjL1ZuBKunGDjE/ggwAX43DwZrJqVwyveTk=
 github.com/KimMachineGun/automemlimit v0.7.5/go.mod h1:QZxpHaGOQoYvFhv/r4u3U0JTC2ZcOwbSr11UZF46UBM=
 github.com/Masterminds/goutils v1.1.1 h1:5nUrii3FMTL5diU80unEVvNevw1nH4+ZV4DSLVJLSYI=
diff --git a/modules/logging/filewriter_test.go b/modules/logging/filewriter_test.go
index 915784b53..de46891fa 100644
--- a/modules/logging/filewriter_test.go
+++ b/modules/logging/filewriter_test.go
@@ -174,6 +174,47 @@ func TestFileRotationPreserveMode(t *testing.T) {
 	}
 }
 
+func TestFileRotationPreserveModeWithUmask(t *testing.T) {
+	m := syscall.Umask(0o022)
+	defer syscall.Umask(m)
+
+	dir, err := os.MkdirTemp("", "caddytest")
+	if err != nil {
+		t.Fatalf("failed to create tempdir: %v", err)
+	}
+	defer os.RemoveAll(dir)
+
+	fpath := path.Join(dir, "test.log")
+
+	roll := true
+	mode := fileMode(0o660)
+	fw := FileWriter{
+		Filename:   fpath,
+		Mode:       mode,
+		Roll:       &roll,
+		RollSizeMB: 1,
+	}
+
+	logger, err := fw.OpenWriter()
+	if err != nil {
+		t.Fatalf("failed to create file: %v", err)
+	}
+	defer logger.Close()
+
+	b := make([]byte, 1024*1024-1000)
+	logger.Write(b)
+	logger.Write(b[0:2000])
+
+	st, err := os.Stat(fpath)
+	if err != nil {
+		t.Fatalf("failed to check file permissions: %v", err)
+	}
+
+	if got := st.Mode().Perm(); got != os.FileMode(mode) {
+		t.Errorf("file mode after rotation is %v, want %v", got, mode)
+	}
+}
+
 func TestFileModeConfig(t *testing.T) {
 	tests := []struct {
 		name    string