From e1d3341b46648ddec59519cc33f50cbb7e8777e7 Mon Sep 17 00:00:00 2001
From: Wolfy-J <wolfy.jd@gmail.com>
Date: Sat, 15 Aug 2026 22:13:42 -0400
Subject: [PATCH] fix manifest decoder bounds

---
 types/io/manifest.go       |  9 +++++++++
 types/io/manifest_test.go  | 37 +++++++++++++++++++++++++++++++++++++
 types/io/reader.go         | 10 ++++++----
 types/io/serialize.go      |  2 --
 types/io/serialize_test.go | 11 +++++++++++
 5 files changed, 63 insertions(+), 6 deletions(-)

diff --git a/types/io/manifest.go b/types/io/manifest.go
index b29743cec..a832ed55f 100644
--- a/types/io/manifest.go
+++ b/types/io/manifest.go
@@ -772,6 +772,9 @@ func DecodeManifest(data []byte) (*Manifest, error) {
 
 	// Types
 	count := r.readUint32()
+	if !r.checkSliceLen(count) {
+		return nil, r.err
+	}
 	for i := uint32(0); i < count; i++ {
 		name := r.readString()
 		m.Types[name] = r.readType()
@@ -779,6 +782,9 @@ func DecodeManifest(data []byte) (*Manifest, error) {
 
 	// Summaries
 	count = r.readUint32()
+	if !r.checkSliceLen(count) {
+		return nil, r.err
+	}
 	for i := uint32(0); i < count; i++ {
 		name := r.readString()
 		m.Summaries[name] = r.readSummary()
@@ -786,6 +792,9 @@ func DecodeManifest(data []byte) (*Manifest, error) {
 
 	// Globals
 	count = r.readUint32()
+	if !r.checkSliceLen(count) {
+		return nil, r.err
+	}
 	for i := uint32(0); i < count; i++ {
 		name := r.readString()
 		m.Globals[name] = r.readType()
diff --git a/types/io/manifest_test.go b/types/io/manifest_test.go
index 4370d4b2b..20bffa2d1 100644
--- a/types/io/manifest_test.go
+++ b/types/io/manifest_test.go
@@ -1,7 +1,10 @@
 package io
 
 import (
+	"bytes"
 	"errors"
+	"fmt"
+	"strings"
 	"testing"
 
 	"github.com/wippyai/go-lua/types/constraint"
@@ -237,6 +240,25 @@ func TestManifest_Encode_Decode(t *testing.T) {
 	}
 }
 
+func TestManifest_Encode_Decode_LargeValidManifest(t *testing.T) {
+	m := NewManifest(strings.Repeat("module/", 32))
+	for i := 0; i < 2048; i++ {
+		m.AddGlobal(fmt.Sprintf("global_%04d", i), typ.String)
+	}
+
+	data, err := m.Encode()
+	if err != nil {
+		t.Fatalf("Encode failed: %v", err)
+	}
+	decoded, err := DecodeManifest(data)
+	if err != nil {
+		t.Fatalf("DecodeManifest failed: %v", err)
+	}
+	if decoded.Path != m.Path || len(decoded.Globals) != len(m.Globals) {
+		t.Fatalf("decoded manifest differs: path=%q globals=%d", decoded.Path, len(decoded.Globals))
+	}
+}
+
 func TestManifest_EnrichedExport_DoesNotApplySummaryToNestedSameName(t *testing.T) {
 	m := NewManifest("test")
 
@@ -331,6 +353,21 @@ func TestDecodeManifest_InvalidMagic(t *testing.T) {
 	}
 }
 
+func TestDecodeManifest_RejectsCollectionLengthBeyondInput(t *testing.T) {
+	var buf bytes.Buffer
+	w := &manifestWriter{typeWriter: &typeWriter{w: &buf}}
+	w.writeUint32(manifestMagic)
+	w.writeByte(manifestVersion)
+	w.writeUint64(0)
+	w.writeString("test")
+	w.writeBool(false)
+	w.writeUint32(1024)
+
+	if _, err := DecodeManifest(buf.Bytes()); !errors.Is(err, ErrCorruptedData) {
+		t.Fatalf("DecodeManifest error = %v", err)
+	}
+}
+
 func TestApplyFunctionSummary_Nil(t *testing.T) {
 	fn := typ.Func().Build()
 	result := ApplyFunctionSummary(fn, nil)
diff --git a/types/io/reader.go b/types/io/reader.go
index 9ce5b13e4..a1138f332 100644
--- a/types/io/reader.go
+++ b/types/io/reader.go
@@ -13,8 +13,10 @@ import (
 	"github.com/wippyai/go-lua/types/typ"
 )
 
-const maxTypeDepth = 32
-const maxTypeNodes = 1024
+const maxTypeDepth = 256
+const maxTypeNodes = 1 << 20
+const maxCollectionLen = 1 << 20
+const maxStringLen = 16 << 20
 
 type typeReader struct {
 	r   *bytes.Reader
@@ -71,7 +73,7 @@ func (r *typeReader) readString() string {
 		return ""
 	}
 
-	if length > maxSliceLen {
+	if length > maxStringLen || uint64(length) > uint64(r.r.Len()) {
 		r.err = ErrCorruptedData
 		return ""
 	}
@@ -87,7 +89,7 @@ func (r *typeReader) readBool() bool {
 }
 
 func (r *typeReader) checkSliceLen(n uint32) bool {
-	if n > maxSliceLen {
+	if n > maxCollectionLen || uint64(n) > uint64(r.r.Len()) {
 		r.err = ErrCorruptedData
 		return false
 	}
diff --git a/types/io/serialize.go b/types/io/serialize.go
index c6c8f0efa..fb342c1b5 100644
--- a/types/io/serialize.go
+++ b/types/io/serialize.go
@@ -42,8 +42,6 @@ var (
 	ErrCorruptedData = errors.New("corrupted type data")
 )
 
-const maxSliceLen = 64
-
 const (
 	annotationArgNil byte = iota
 	annotationArgString
diff --git a/types/io/serialize_test.go b/types/io/serialize_test.go
index 5a125314e..0ba0b6d88 100644
--- a/types/io/serialize_test.go
+++ b/types/io/serialize_test.go
@@ -1397,6 +1397,17 @@ func TestDecode_ReadString_Empty(t *testing.T) {
 	}
 }
 
+func TestDecode_ReadString_RejectsLengthBeyondInput(t *testing.T) {
+	var buf bytes.Buffer
+	tw := &typeWriter{w: &buf}
+	tw.writeUint32(1024)
+
+	r := &typeReader{r: bytes.NewReader(buf.Bytes())}
+	if got := r.readString(); got != "" || !errors.Is(r.err, ErrCorruptedData) {
+		t.Fatalf("readString() = %q, err=%v", got, r.err)
+	}
+}
+
 func TestDecode_Literal_UnknownBase(t *testing.T) {
 	// kind.Literal is 23 (0x17)
 	var buf bytes.Buffer