net/http: ParseMultipartForm panic when the body==nil #48206
Description
What version of Go are you using (go version)?
go version go1.17 windows/amd64
Does this issue reproduce with the latest release?
yes
What operating system and processor architecture are you using (go env)?
go env Output
set GO111MODULE=auto set GOARCH=amd64 set GOBIN= set GOCACHE=C:\Users\xx\AppData\Local\go-build set GOENV=C:\Users\xx\AppData\Roaming\go\env set GOEXE=.exe set GOEXPERIMENT= set GOFLAGS= set GOHOSTARCH=amd64 set GOHOSTOS=windows set GOINSECURE= set GOMODCACHE=C:\Users\xx\go\pkg\mod set GONOPROXY= set GONOSUMDB= set GOOS=windows set GOPATH=C:\Users\xx\go set GOPRIVATE= set GOPROXY=https://goproxy.io,direct set GOROOT=c:\go set GOSUMDB=sum.golang.org set GOTMPDIR= set GOTOOLDIR=c:\go\pkg\tool\windows_amd64 set GOVCS= set GOVERSION=go1.17 set GCCGO=gccgo set AR=ar set CC=gcc set CXX=g++ set CGO_ENABLED=1 set GOMOD= set CGO_CFLAGS=-g -O2 set CGO_CPPFLAGS= set CGO_CXXFLAGS=-g -O2 set CGO_FFLAGS=-g -O2 set CGO_LDFLAGS=-g -O2 set PKG_CONFIG=pkg-config set GOGCCFLAGS=-m64 -mthreads -fno-caret-diagnostics -Qunused-arguments -fmessage-length=0 -fdebug-prefix-map=C:\Users\xx\AppData\Local\Temp\go-build2679503516=/tmp/go-build -gno-record-gcc-switches
What did you do?
package main
import (
"bytes"
"fmt"
"mime/multipart"
"net/http"
)
func main() {
buf := new(bytes.Buffer)
mw := multipart.NewWriter(buf)
mw.Close()
Request, _ := http.NewRequest("POST", "/", nil)
Request.Header.Set("Content-Type", mw.FormDataContentType())
f, fh, err := Request.FormFile("file")
if err != nil {
fmt.Printf("%#+v\n", err)
return
}
f.Close()
fmt.Printf("%#+v\n", fh)
return
}
What did you expect to see?
I would like to see an error.
errors.New("missing form body")
What did you see instead?
panic: runtime error: invalid memory address or nil pointer dereference
[signal 0xc0000005 code=0x0 addr=0x18 pc=0x77b632]
goroutine 1 [running]:
mime/multipart.(*stickyErrorReader).Read(0xc00005a500, {0xc0000da000, 0x927640, 0x0})
c:/go/src/mime/multipart/multipart.go:127 +0x32
bufio.(*Reader).fill(0xc000066180)
c:/go/src/bufio/bufio.go:101 +0x103
bufio.(*Reader).ReadSlice(0xc000066180, 0x98)
c:/go/src/bufio/bufio.go:360 +0x2f
mime/multipart.(*Reader).nextPart(0xc000022080, 0xf8)
c:/go/src/mime/multipart/multipart.go:335 +0xb6
mime/multipart.(*Reader).NextPart(...)
c:/go/src/mime/multipart/multipart.go:314
mime/multipart.(*Reader).readForm(0xc0000d4000, 0x2000000)
c:/go/src/mime/multipart/formdata.go:52 +0x178
mime/multipart.(*Reader).ReadForm(...)
c:/go/src/mime/multipart/formdata.go:31
net/http.(*Request).ParseMultipartForm(0xc0000d4000, 0x6ad007)
c:/go/src/net/http/request.go:1318 +0xa5
net/http.(*Request).FormFile(0xc0000d4000, {0x7e207c, 0x4})
c:/go/src/net/http/request.go:1376 +0x4f
main.main()
D:/gocode/src/ucenter/app/test/httpformfile/main.go:18 +0x1bb
exit status 2