NOMERGE: go1.25.5.unalign fix

VERSION

@@ -1,2 +1,2 @@
-go1.25rc2
-time 2025-07-02T21:52:16Z
+go1.25.5-kb
+time 2025-12-18T10:09:51Z

doc/go_spec.html

@@ -1,6 +1,6 @@
 <!--{
 	"Title": "The Go Programming Language Specification",
-	"Subtitle": "Language version go1.25 (Feb 25, 2025)",
+	"Subtitle": "Language version go1.25 (Aug 12, 2025)",
 	"Path": "/ref/spec"
 }-->
 

doc/godebug.md

@@ -153,6 +153,16 @@ for example,
 see the [runtime documentation](/pkg/runtime#hdr-Environment_Variables)
 and the [go command documentation](/cmd/go#hdr-Build_and_test_caching).
 
+### Go 1.26
+
+Go 1.26 added a new `httpcookiemaxnum` setting that controls the maximum number
+of cookies that net/http will accept when parsing HTTP headers. If the number of
+cookie in a header exceeds the number set in `httpcookiemaxnum`, cookie parsing
+will fail early. The default value is `httpcookiemaxnum=3000`. Setting
+`httpcookiemaxnum=0` will allow the cookie parsing to accept an indefinite
+number of cookies. To avoid denial of service attacks, this setting and default
+was backported to Go 1.25.2 and Go 1.24.8.
+
 ### Go 1.25
 
 Go 1.25 added a new `decoratemappings` setting that controls whether the Go

lib/fips140/fips140.sum

@@ -9,4 +9,4 @@
 #
 #	go test cmd/go/internal/fips140 -update
 #
-v1.0.0.zip b50508feaeff05d22516b21e1fd210bbf5d6a1e422eaf2cfa23fe379342713b8
+v1.0.0-c2097c7c.zip daf3614e0406f67ae6323c902db3f953a1effb199142362a039e7526dfb9368b

lib/fips140/inprocess.txt

@@ -1 +1 @@
-v1.0.0
+v1.0.0-c2097c7c

lib/fips140/v1.0.0.txt

@@ -0,0 +1 @@
+v1.0.0-c2097c7c

src/archive/tar/common.go

@@ -39,6 +39,7 @@ var (
 	errMissData        = errors.New("archive/tar: sparse file references non-existent data")
 	errUnrefData       = errors.New("archive/tar: sparse file contains unreferenced data")
 	errWriteHole       = errors.New("archive/tar: write non-NUL byte in sparse hole")
+	errSparseTooLong   = errors.New("archive/tar: sparse map too long")
 )
 
 type headerError []string

src/archive/tar/reader.go

@@ -531,12 +531,17 @@ func readGNUSparseMap1x0(r io.Reader) (sparseDatas, error) {
 		cntNewline int64
 		buf        bytes.Buffer
 		blk        block
+		totalSize  int
 	)
 
 	// feedTokens copies data in blocks from r into buf until there are
 	// at least cnt newlines in buf. It will not read more blocks than needed.
 	feedTokens := func(n int64) error {
 		for cntNewline < n {
+			totalSize += len(blk)
+			if totalSize > maxSpecialFileSize {
+				return errSparseTooLong
+			}
 			if _, err := mustReadFull(r, blk[:]); err != nil {
 				return err
 			}
@@ -569,8 +574,8 @@ func readGNUSparseMap1x0(r io.Reader) (sparseDatas, error) {
 	}
 
 	// Parse for all member entries.
-	// numEntries is trusted after this since a potential attacker must have
-	// committed resources proportional to what this library used.
+	// numEntries is trusted after this since feedTokens limits the number of
+	// tokens based on maxSpecialFileSize.
 	if err := feedTokens(2 * numEntries); err != nil {
 		return nil, err
 	}

src/archive/tar/reader_test.go

@@ -621,6 +621,11 @@ func TestReader(t *testing.T) {
 			},
 			Format: FormatPAX,
 		}},
+	}, {
+		// Small compressed file that uncompresses to
+		// a file with a very large GNU 1.0 sparse map.
+		file: "testdata/gnu-sparse-many-zeros.tar.bz2",
+		err:  errSparseTooLong,
 	}}
 
 	for _, v := range vectors {

src/cmd/cgo/internal/testout/out_test.go

@@ -0,0 +1,144 @@
+// Copyright 2025 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package out_test
+
+import (
+	"bufio"
+	"bytes"
+	"fmt"
+	"internal/testenv"
+	"internal/goarch"
+	"os"
+	"path/filepath"
+	"regexp"
+	"strconv"
+	"strings"
+	"testing"
+)
+
+type methodAlign struct {
+	Method string
+	Align  int
+}
+
+var wantAligns = map[string]int{
+	"ReturnEmpty":         1,
+	"ReturnOnlyUint8":     1,
+	"ReturnOnlyUint16":    2,
+	"ReturnOnlyUint32":    4,
+	"ReturnOnlyUint64":    goarch.PtrSize,
+	"ReturnOnlyInt":       goarch.PtrSize,
+	"ReturnOnlyPtr":       goarch.PtrSize,
+	"ReturnByteSlice":     goarch.PtrSize,
+	"ReturnString":        goarch.PtrSize,
+	"InputAndReturnUint8": 1,
+	"MixedTypes":          goarch.PtrSize,
+}
+
+// TestAligned tests that the generated _cgo_export.c file has the wanted
+// align attributes for struct types used as arguments or results of
+// //exported functions.
+func TestAligned(t *testing.T) {
+	testenv.MustHaveGoRun(t)
+	testenv.MustHaveCGO(t)
+
+	testdata, err := filepath.Abs("testdata")
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	objDir := t.TempDir()
+
+	cmd := testenv.Command(t, testenv.GoToolPath(t), "tool", "cgo",
+		"-objdir", objDir,
+		filepath.Join(testdata, "aligned.go"))
+	cmd.Stderr = new(bytes.Buffer)
+
+	err = cmd.Run()
+	if err != nil {
+		t.Fatalf("%#q: %v\n%s", cmd, err, cmd.Stderr)
+	}
+
+	haveAligns, err := parseAlign(filepath.Join(objDir, "_cgo_export.c"))
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	// Check that we have all the wanted methods
+	if len(haveAligns) != len(wantAligns) {
+		t.Fatalf("have %d methods with aligned, want %d", len(haveAligns), len(wantAligns))
+	}
+
+	for i := range haveAligns {
+		method := haveAligns[i].Method
+		haveAlign := haveAligns[i].Align
+
+		wantAlign, ok := wantAligns[method]
+		if !ok {
+			t.Errorf("method %s: have aligned %d, want missing entry", method, haveAlign)
+		} else if haveAlign != wantAlign {
+			t.Errorf("method %s: have aligned %d, want %d", method, haveAlign, wantAlign)
+		}
+	}
+}
+
+func parseAlign(filename string) ([]methodAlign, error) {
+	file, err := os.Open(filename)
+	if err != nil {
+		return nil, fmt.Errorf("failed to open file: %w", err)
+	}
+	defer file.Close()
+
+	var results []methodAlign
+	scanner := bufio.NewScanner(file)
+
+	// Regex to match function declarations like "struct MethodName_return MethodName("
+	funcRegex := regexp.MustCompile(`^struct\s+(\w+)_return\s+(\w+)\(`)
+	// Regex to match simple function declarations like "GoSlice MethodName("
+	simpleFuncRegex := regexp.MustCompile(`^Go\w+\s+(\w+)\(`)
+	// Regex to match void-returning exported functions like "void ReturnEmpty("
+	voidFuncRegex := regexp.MustCompile(`^void\s+(\w+)\(`)
+	// Regex to match align attributes like "__attribute__((aligned(8)))"
+	alignRegex := regexp.MustCompile(`__attribute__\(\(aligned\((\d+)\)\)\)`)
+
+	var currentMethod string
+
+	for scanner.Scan() {
+		line := strings.TrimSpace(scanner.Text())
+
+		// Check if this line declares a function with struct return type
+		if matches := funcRegex.FindStringSubmatch(line); matches != nil {
+			currentMethod = matches[2] // Extract the method name
+		} else if matches := simpleFuncRegex.FindStringSubmatch(line); matches != nil {
+			// Check if this line declares a function with simple return type (like GoSlice)
+			currentMethod = matches[1] // Extract the method name
+		} else if matches := voidFuncRegex.FindStringSubmatch(line); matches != nil {
+			// Check if this line declares a void-returning function
+			currentMethod = matches[1] // Extract the method name
+		}
+
+		// Check if this line contains align information
+		if alignMatches := alignRegex.FindStringSubmatch(line); alignMatches != nil && currentMethod != "" {
+			alignStr := alignMatches[1]
+			align, err := strconv.Atoi(alignStr)
+			if err != nil {
+				// Skip this entry if we can't parse the align as integer
+				currentMethod = ""
+				continue
+			}
+			results = append(results, methodAlign{
+				Method: currentMethod,
+				Align:  align,
+			})
+			currentMethod = "" // Reset for next method
+		}
+	}
+
+	if err := scanner.Err(); err != nil {
+		return nil, fmt.Errorf("error reading file: %w", err)
+	}
+
+	return results, nil
+}

src/cmd/cgo/internal/testout/testdata/aligned.go

@@ -0,0 +1,63 @@
+// Copyright 2025 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import "C"
+
+//export ReturnEmpty
+func ReturnEmpty() {
+	return
+}
+
+//export ReturnOnlyUint8
+func ReturnOnlyUint8() (uint8, uint8, uint8) {
+	return 1, 2, 3
+}
+
+//export ReturnOnlyUint16
+func ReturnOnlyUint16() (uint16, uint16, uint16) {
+	return 1, 2, 3
+}
+
+//export ReturnOnlyUint32
+func ReturnOnlyUint32() (uint32, uint32, uint32) {
+	return 1, 2, 3
+}
+
+//export ReturnOnlyUint64
+func ReturnOnlyUint64() (uint64, uint64, uint64) {
+	return 1, 2, 3
+}
+
+//export ReturnOnlyInt
+func ReturnOnlyInt() (int, int, int) {
+	return 1, 2, 3
+}
+
+//export ReturnOnlyPtr
+func ReturnOnlyPtr() (*int, *int, *int) {
+	a, b, c := 1, 2, 3
+	return &a, &b, &c
+}
+
+//export ReturnString
+func ReturnString() string {
+	return "hello"
+}
+
+//export ReturnByteSlice
+func ReturnByteSlice() []byte {
+	return []byte{1, 2, 3}
+}
+
+//export InputAndReturnUint8
+func InputAndReturnUint8(a, b, c uint8) (uint8, uint8, uint8) {
+	return a, b, c
+}
+
+//export MixedTypes
+func MixedTypes(a uint8, b uint16, c uint32, d uint64, e int, f *int) (uint8, uint16, uint32, uint64, int, *int) {
+	return a, b, c, d, e, f
+}

src/cmd/cgo/out.go

@@ -949,6 +949,8 @@ func (p *Package) writeExports(fgo2, fm, fgcc, fgcch io.Writer) {
 		fmt.Fprintf(gotype, "struct {\n")
 		off := int64(0)
 		npad := 0
+		// the align is at least 1 (for char)
+		maxAlign := int64(1)
 		argField := func(typ ast.Expr, namePat string, args ...interface{}) {
 			name := fmt.Sprintf(namePat, args...)
 			t := p.cgoType(typ)
@@ -963,6 +965,11 @@ func (p *Package) writeExports(fgo2, fm, fgcc, fgcch io.Writer) {
 			noSourceConf.Fprint(gotype, fset, typ)
 			fmt.Fprintf(gotype, "\n")
 			off += t.Size
+			// keep track of the maximum alignment among all fields
+			// so that we can align the struct correctly
+			if t.Align > maxAlign {
+				maxAlign = t.Align
+			}
 		}
 		if fn.Recv != nil {
 			argField(fn.Recv.List[0].Type, "recv")
@@ -1051,7 +1058,11 @@ func (p *Package) writeExports(fgo2, fm, fgcc, fgcch io.Writer) {
 		// string.h for memset, and is also robust to C++
 		// types with constructors. Both GCC and LLVM optimize
 		// this into just zeroing _cgo_a.
-		fmt.Fprintf(fgcc, "\ttypedef %s %v _cgo_argtype;\n", ctype.String(), p.packedAttribute())
+		//
+		// The struct should be aligned to the maximum alignment
+		// of any of its fields. This to avoid alignment
+		// issues.
+		fmt.Fprintf(fgcc, "\ttypedef %s %v __attribute__((aligned(%d))) _cgo_argtype;\n", ctype.String(), p.packedAttribute(), maxAlign)
 		fmt.Fprintf(fgcc, "\tstatic _cgo_argtype _cgo_zero;\n")
 		fmt.Fprintf(fgcc, "\t_cgo_argtype _cgo_a = _cgo_zero;\n")
 		if gccResult != "void" && (len(fntype.Results.List) > 1 || len(fntype.Results.List[0].Names) > 1) {

src/cmd/compile/internal/dwarfgen/dwarf.go

@@ -128,14 +128,29 @@ func Info(ctxt *obj.Link, fnsym *obj.LSym, infosym *obj.LSym, curfn obj.Func) (s
 	// already referenced by a dwarf var, attach an R_USETYPE relocation to
 	// the function symbol to insure that the type included in DWARF
 	// processing during linking.
+	// Do the same with R_USEIFACE relocations from the function symbol for the
+	// same reason.
+	// All these R_USETYPE relocations are only looked at if the function
+	// survives deadcode elimination in the linker.
 	typesyms := []*obj.LSym{}
 	for t := range fnsym.Func().Autot {
 		typesyms = append(typesyms, t)
 	}
+	for i := range fnsym.R {
+		if fnsym.R[i].Type == objabi.R_USEIFACE && !strings.HasPrefix(fnsym.R[i].Sym.Name, "go:itab.") {
+			// Types referenced through itab will be referenced from somewhere else
+			typesyms = append(typesyms, fnsym.R[i].Sym)
+		}
+	}
 	slices.SortFunc(typesyms, func(a, b *obj.LSym) int {
 		return strings.Compare(a.Name, b.Name)
 	})
+	var lastsym *obj.LSym
 	for _, sym := range typesyms {
+		if sym == lastsym {
+			continue
+		}
+		lastsym = sym
 		infosym.AddRel(ctxt, obj.Reloc{Type: objabi.R_USETYPE, Sym: sym})
 	}
 	fnsym.Func().Autot = nil