When handling errors in storageHandler check underlying error (#13178)

Unfortunately there was a mistake in #13164 which fails to handle
os.PathError wrapping an os.ErrNotExist

Signed-off-by: Andrew Thornton <art27@cantab.net>

Co-authored-by: techknowlogick <techknowlogick@gitea.io>

modules/storage/minio.go

@@ -32,7 +32,7 @@ type minioObject struct {
 func (m *minioObject) Stat() (os.FileInfo, error) {
 	oi, err := m.Object.Stat()
 	if err != nil {
-		return nil, err
+		return nil, convertMinioErr(err)
 	}
 
 	return &minioFileInfo{oi}, nil

routers/routes/routes.go

@@ -7,6 +7,7 @@ package routes
 import (
 	"bytes"
 	"encoding/gob"
+	"errors"
 	"fmt"
 	"io"
 	"net/http"
@@ -127,7 +128,7 @@ func storageHandler(storageSetting setting.Storage, prefix string, objStore stor
 			rPath := strings.TrimPrefix(req.RequestURI, "/"+prefix)
 			u, err := objStore.URL(rPath, path.Base(rPath))
 			if err != nil {
-				if err == os.ErrNotExist {
+				if os.IsNotExist(err) || errors.Is(err, os.ErrNotExist) {
 					log.Warn("Unable to find %s %s", prefix, rPath)
 					ctx.Error(404, "file not found")
 					return
@@ -160,7 +161,7 @@ func storageHandler(storageSetting setting.Storage, prefix string, objStore stor
 		//If we have matched and access to release or issue
 		fr, err := objStore.Open(rPath)
 		if err != nil {
-			if err == os.ErrNotExist {
+			if os.IsNotExist(err) || errors.Is(err, os.ErrNotExist) {
 				log.Warn("Unable to find %s %s", prefix, rPath)
 				ctx.Error(404, "file not found")
 				return