What version of Go are you using (go version)?

1.20

Does this issue reproduce with the latest release?

Yep

What operating system and processor architecture are you using (go env)?

Windows and Linux

What did you do?

package main
import (
	"crypto/cipher"
	"crypto/rand"
	"crypto/aes"
	"bytes"
	"encoding/hex"
	"flag"
	"fmt"
	"crypto/sha256"
	"golang.org/x/crypto/pbkdf2"
	"io"
	"log"
	"os"
)

	var dec = flag.Bool("d", false, "Decrypt instead Encrypt.")
	var iter = flag.Int("i", 1024, "Iterations. (for PBKDF2)")
	var key = flag.String("k", "", "128-bit key to Encrypt/Decrypt.")
	var pbkdf = flag.String("p", "", "PBKDF2.")
	var salt = flag.String("s", "", "Salt. (for PBKDF2)")

func main() {
    flag.Parse()

        if (len(os.Args) < 1) {
	fmt.Println("Usage of",os.Args[0]+":")
        flag.PrintDefaults()
        os.Exit(1)
        }
	
	var keyHex string
	var prvRaw []byte
	if *pbkdf != "" {
	prvRaw = pbkdf2.Key([]byte(*pbkdf), []byte(*salt), *iter, 32, sha256.New)
	keyHex = hex.EncodeToString(prvRaw)
	} else {
	keyHex = *key
	}
	var key []byte
	var err error
	if keyHex == "" {
		key = make([]byte, 32)
		_, err = io.ReadFull(rand.Reader, key)
		if err != nil {
                        log.Fatal(err)
		}
		fmt.Fprintln(os.Stderr, "Key=", hex.EncodeToString(key))
	} else {
		key, err = hex.DecodeString(keyHex)
		if err != nil {
                        log.Fatal(err)
		}
		if len(key) != 32 {
                        log.Fatal(err)
		}
	}

	block, err := aes.NewCipher(key)
	if err != nil {
		panic(err.Error())
	}

	aead, err := cipher.NewGCM(block)
	if err != nil {
		panic(err.Error())
	}

	if *dec == false {
		buf := bytes.NewBuffer(nil)
		data := os.Stdin 
		io.Copy(buf, data)
		msg := buf.Bytes()

		nonce := make([]byte, aead.NonceSize(), aead.NonceSize()+len(msg)+aead.Overhead())

		out := aead.Seal(nonce, nonce, msg, nil)
		fmt.Printf("%s", out)

	        os.Exit(0)
	}

	if *dec == true {
		buf := bytes.NewBuffer(nil)
		data := os.Stdin 
		io.Copy(buf, data)
		msg := buf.Bytes()

		nonce, msg := msg[:aead.NonceSize()], msg[aead.NonceSize():]

		out, err := aead.Open(nil, nonce, msg, nil)
		if err != nil {
			panic(err)
		}
		fmt.Printf("%s", out)

	        os.Exit(0)
	}
}

What did you expect to see?

Based on NIST SP 800-38D (GCM) section 5.2.1.1, it seems that the maximum length of plaintext is 2^39-256 bits ~ 64 GB.

What did you see instead?

Files larger than 1.5GB 250MB will result in a memory error with any AEAD operating mode, it is not possible to encrypt 1.5GB 250MB files:

runtime: out of memory: cannot allocate 1073741824-byte block (1077837824 in use)
fatal error: out of memory

runtime stack:
runtime.throw(0x4d9c26, 0xd)
c:/go/src/runtime/panic.go:617 +0x64
runtime.largeAlloc(0x3ffffe00, 0x11c10101, 0x11c1e000)
c:/go/src/runtime/malloc.go:1057 +0x10f
runtime.mallocgc.func1()
c:/go/src/runtime/malloc.go:950 +0x39
runtime.systemstack(0x447245)
c:/go/src/runtime/asm_386.s:396 +0x53
runtime.mstart()
c:/go/src/runtime/proc.go:1153

goroutine 1 [running]:
runtime.systemstack_switch()
c:/go/src/runtime/asm_386.s:357 fp=0x11c56d94 sp=0x11c56d90 pc=0x447300
runtime.mallocgc(0x3ffffe00, 0x4c0340, 0x1, 0x11c56e00)
c:/go/src/runtime/malloc.go:949 +0x65b fp=0x11c56de8 sp=0x11c56d94 pc=0x40968b
runtime.makeslice(0x4c0340, 0x3ffffe00, 0x3ffffe00, 0x527ffe00)
c:/go/src/runtime/slice.go:49 +0x4f fp=0x11c56dfc sp=0x11c56de8 pc=0x43521f
bytes.makeSlice(0x3ffffe00, 0x0, 0x0, 0x0)
c:/go/src/bytes/buffer.go:232 +0x61 fp=0x11c56e10 sp=0x11c56dfc pc=0x491821
bytes.(*Buffer).grow(0x11c3bb60, 0x200, 0x10000000)
c:/go/src/bytes/buffer.go:145 +0x12a fp=0x11c56e38 sp=0x11c56e10 pc=0x4913ca
bytes.(*Buffer).ReadFrom(0x11c3bb60, 0x4f5920, 0x11c380d8, 0x3880e0, 0x11c3bb60, 0x1, 0x75)
c:/go/src/bytes/buffer.go:205 +0x45 fp=0x11c56e74 sp=0x11c56e38 pc=0x491645
io.copyBuffer(0x4f5880, 0x11c3bb60, 0x4f5920, 0x11c380d8, 0x0, 0x0, 0x0, 0x0, 0x0, 0x4d8408, ...)
c:/go/src/io/io.go:388 +0x29a fp=0x11c56eb4 sp=0x11c56e74 pc=0x44e65a
io.Copy(...)
c:/go/src/io/io.go:364
main.main()
H:/PGMM/crypter/aes-gcm/main.go:93 +0x5c6 fp=0x11c56fd0 sp=0x11c56eb4 pc=0x4a9366
runtime.main()
c:/go/src/runtime/proc.go:200 +0x1d7 fp=0x11c56ff0 sp=0x11c56fd0 pc=0x427937
runtime.goexit()
c:/go/src/runtime/asm_386.s:1321 +0x1 fp=0x11c56ff4 sp=0x11c56ff0 pc=0x448b21