feat: add ReadFileWithSizeLimit and use it on x/wasm (#696)

* Add `ReadFileWithSizeLimit` and use it on `x/wasm`

* Update CHANGELOG.md

* Refactor internal/os into x/wasm

* Revert "Refactor internal/os into x/wasm"

This reverts commit 200df68.

* Use `ReadFileWithSizeLimit` on `x/distribution`

* Modify to one liner

CHANGELOG.md

@@ -73,6 +73,7 @@ Ref: https://keepachangelog.com/en/1.0.0/
 * (refactor) [\#685](https://github.com/line/lbm-sdk/pull/685) remove x/foundation UpdateValidatorAuthsProposal
 * (x/foundation) [\#686](https://github.com/line/lbm-sdk/pull/686) remove `Minthreshold` and `MinPercentage` from x/foundation config
 * (x/foundation) [\#693](https://github.com/line/lbm-sdk/pull/693) add pool to the state of x/foundation
+* (x/wasm,distribution) [\#696](https://github.com/line/lbm-sdk/pull/696) x/wasm,distribution - add checking a file size before reading it
 * (x/foundation) [\#698](https://github.com/line/lbm-sdk/pull/698) update x/group relevant logic in x/foundation
 
 ### Bug Fixes

internal/os/file.go

@@ -0,0 +1,58 @@
+package os
+
+import (
+	"fmt"
+	"io"
+	"os"
+)
+
+// ReadFileWithSizeLimit expanded os.ReadFile for checking the file size before reading it
+func ReadFileWithSizeLimit(name string, sizeLimit int64) ([]byte, error) {
+	f, err := os.Open(name)
+	if err != nil {
+		return nil, err
+	}
+	defer func() {
+		err := f.Close()
+		if err != nil {
+			fmt.Printf("Cannot close the file: %s\n", name)
+		}
+	}()
+
+	var size int
+	if info, err := f.Stat(); err == nil {
+		size64 := info.Size()
+		// Check the file size
+		if size64 > sizeLimit {
+			return nil, fmt.Errorf("the file is too large: %s, size limit over > %d", name, sizeLimit)
+		}
+		if int64(int(size64)) == size64 {
+			size = int(size64)
+		}
+	}
+	size++ // one byte for final read at EOF
+
+	// If a file claims a small size, read at least 512 bytes.
+	// In particular, files in Linux's /proc claim size 0 but
+	// then do not work right if read in small pieces,
+	// so an initial read of 1 byte would not work correctly.
+	if size < 512 {
+		size = 512
+	}
+
+	data := make([]byte, 0, size)
+	for {
+		if len(data) >= cap(data) {
+			d := append(data[:cap(data)], 0)
+			data = d[:len(data)]
+		}
+		n, err := f.Read(data[len(data):cap(data)])
+		data = data[:len(data)+n]
+		if err != nil {
+			if err == io.EOF {
+				err = nil
+			}
+			return data, err
+		}
+	}
+}

internal/os/file_test.go

@@ -0,0 +1,42 @@
+package os
+
+import (
+	"os"
+	"reflect"
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+func TestReadFileWithSizeLimit(t *testing.T) {
+	filename := "file.go"
+	file, err := os.ReadFile(filename)
+	require.NoError(t, err)
+
+	type args struct {
+		name      string
+		sizeLimit int64
+	}
+	tests := []struct {
+		name    string
+		args    args
+		want    []byte
+		wantErr bool
+	}{
+		{"cannot open error", args{"", 0}, nil, true},
+		{"size limit over error", args{filename, 0}, nil, true},
+		{"simple reading file success", args{filename, 100000}, file, false},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			got, err := ReadFileWithSizeLimit(tt.args.name, tt.args.sizeLimit)
+			if (err != nil) != tt.wantErr {
+				t.Errorf("ReadFileWithSizeLimit() error = %v, wantErr %v", err, tt.wantErr)
+				return
+			}
+			if !reflect.DeepEqual(got, tt.want) {
+				t.Errorf("ReadFileWithSizeLimit() got = %v, want %v", got, tt.want)
+			}
+		})
+	}
+}

x/distribution/client/cli/utils.go

@@ -1,17 +1,19 @@
 package cli
 
 import (
-	"os"
-
 	"github.com/line/lbm-sdk/codec"
+	"github.com/line/lbm-sdk/internal/os"
 	"github.com/line/lbm-sdk/x/distribution/types"
 )
 
 // ParseCommunityPoolSpendProposalWithDeposit reads and parses a CommunityPoolSpendProposalWithDeposit from a file.
 func ParseCommunityPoolSpendProposalWithDeposit(cdc codec.JSONCodec, proposalFile string) (types.CommunityPoolSpendProposalWithDeposit, error) {
 	proposal := types.CommunityPoolSpendProposalWithDeposit{}
 
-	contents, err := os.ReadFile(proposalFile)
+	// 2M size limit is enough for a proposal.
+	// Check the proposals:
+	// https://hubble.figment.io/cosmos/chains/cosmoshub-4/governance
+	contents, err := os.ReadFileWithSizeLimit(proposalFile, 2*1024*1024)
 	if err != nil {
 		return proposal, err
 	}

x/wasm/client/cli/tx.go

@@ -3,9 +3,10 @@ package cli
 import (
 	"errors"
 	"fmt"
-	"os"
 	"strconv"
 
+	"github.com/line/lbm-sdk/internal/os"
+
 	"github.com/spf13/cobra"
 	flag "github.com/spf13/pflag"
 
@@ -82,7 +83,7 @@ func StoreCodeCmd() *cobra.Command {
 }
 
 func parseStoreCodeArgs(file string, sender sdk.AccAddress, flags *flag.FlagSet) (types.MsgStoreCode, error) {
-	wasm, err := os.ReadFile(file)
+	wasm, err := os.ReadFileWithSizeLimit(file, int64(types.MaxWasmSize))
 	if err != nil {
 		return types.MsgStoreCode{}, err
 	}
@@ -264,7 +265,7 @@ func StoreCodeAndInstantiateContractCmd() *cobra.Command {
 }
 
 func parseStoreCodeAndInstantiateContractArgs(file string, initMsg string, sender sdk.AccAddress, flags *flag.FlagSet) (lbmtypes.MsgStoreCodeAndInstantiateContract, error) {
-	wasm, err := os.ReadFile(file)
+	wasm, err := os.ReadFileWithSizeLimit(file, int64(types.MaxWasmSize))
 	if err != nil {
 		return lbmtypes.MsgStoreCodeAndInstantiateContract{}, err
 	}