fix(packages): validate module version in goproxy ParsePackage (#38104)

**Unvalidated version in goproxy ParsePackage**
The module version is read straight from the zip directory path and
never checked, so a crafted upload can leave a newline in it;
`EnumeratePackageVersions` then writes each stored version on its own
line for the `@v/list` endpoint, letting a module advertise fabricated
versions to `go` clients. Validated the parsed version with
`semver.IsValid` inside the parser, matching the version checks the
other package parsers already do.

Co-authored-by: Lunny Xiao <xiaolunwen@gmail.com>

modules/packages/goproxy/metadata.go

@@ -10,6 +10,8 @@ import (
 	"strings"
 
 	"gitea.dev/modules/util"
+
+	"golang.org/x/mod/semver"
 )
 
 const (
@@ -20,6 +22,7 @@ const (
 
 var (
 	ErrInvalidStructure  = util.NewInvalidArgumentErrorf("package has invalid structure")
+	ErrInvalidVersion    = util.NewInvalidArgumentErrorf("package version is invalid")
 	ErrGoModFileTooLarge = util.NewInvalidArgumentErrorf("go.mod file is too large")
 )
 
@@ -54,6 +57,13 @@ func ParsePackage(r io.ReaderAt, size int64) (*Package, error) {
 				Name:    strings.TrimSuffix(nameAndVersion, "@"+parts[1]),
 				Version: versionParts[0],
 			}
+
+			// the version is taken verbatim from the zip path and later written
+			// one per line into the @v/list proxy response, so it has to be a
+			// valid module version (no newlines or other stray characters)
+			if !semver.IsValid(p.Version) {
+				return nil, ErrInvalidVersion
+			}
 		}
 
 		if len(versionParts) > 1 {