net/http: fix nil body causing ParseMultipartForm to panic
ParseMultipartForm relies on a valid multipartReader, if the request body is nil,
the multipartReader should return an error. This way ParseMultipartForm can return
an error instead of causing mr.ReadForm(maxMemory) to panic
Fixes #48206
Change-Id: Ief906f2340c7ab29cacbd5f56892117202a0b911
Reviewed-on: https://go-review.googlesource.com/c/go/+/384454
Trust: Damien Neil <dneil@google.com>
Run-TryBot: Damien Neil <dneil@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org> Reviewed-by: Damien Neil <dneil@google.com> Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Trust: Brad Fitzpatrick <bradfitz@golang.org>