--- a/pkg/controllers/srimports.go	Fri Jan 31 17:11:30 2020 +0100
+++ b/pkg/controllers/srimports.go	Fri Jan 31 23:17:37 2020 +0100
@@ -40,7 +40,7 @@
 
 const (
 	soundingResultName    = "soundingresult"
-	maxSoundingResultSize = 25 * 1024 * 1024
+	maxSoundingResultSize = 50 * 1024 * 1024
 )
 
 func fetchSoundingResult(req *http.Request) (string, error) {
@@ -63,11 +63,12 @@
 		return dst, nil
 	}
 
-	return misc.StoreUploadedFile(
+	return misc.StoreUploadedFileCheck(
 		req,
 		soundingResultName,
 		"sr.zip",
 		maxSoundingResultSize,
+		true,
 	)
 }
 
@@ -194,11 +195,12 @@
 func uploadSoundingResult(req *http.Request) (jr mw.JSONResult, err error) {
 
 	var dir string
-	if dir, err = misc.StoreUploadedFile(
+	if dir, err = misc.StoreUploadedFileCheck(
 		req,
 		soundingResultName,
 		"sr.zip",
 		maxSoundingResultSize,
+		true,
 	); err != nil {
 		return
 	}

--- a/pkg/misc/http.go	Fri Jan 31 17:11:30 2020 +0100
+++ b/pkg/misc/http.go	Fri Jan 31 23:17:37 2020 +0100
@@ -15,6 +15,7 @@
 
 import (
 	"bufio"
+	"fmt"
 	"io"
 	"io/ioutil"
 	"net/http"
@@ -30,7 +31,14 @@
 // the given file name.
 // If the file is long than the given limit maxSize
 // this function returns an error.
-func StoreUploadedFile(req *http.Request, field, fname string, maxSize int64) (string, error) {
+func StoreUploadedFile(
+	req *http.Request,
+	field, fname string,
+	maxSize int64) (string, error) {
+	return StoreUploadedFileCheck(req, field, fname, maxSize, false)
+}
+
+func StoreUploadedFileCheck(req *http.Request, field, fname string, maxSize int64, errorOverMax bool) (string, error) {
 
 	// Check for direct upload.
 	f, _, err := req.FormFile(field)
@@ -52,14 +60,34 @@
 
 	out := bufio.NewWriter(o)
 
-	if _, err = io.Copy(out, io.LimitReader(f, maxSize)); err != nil {
+	// Little trick to check if we are over the limit.
+	size := maxSize
+	if errorOverMax {
+		size++
+	}
+
+	cleanup := func() {
 		o.Close()
 		os.RemoveAll(dir)
+	}
+
+	r, err := io.Copy(out, io.LimitReader(f, size))
+	if err != nil {
+		cleanup()
 		return "", err
 	}
 
+	if errorOverMax && r > maxSize {
+		cleanup()
+		return "", fmt.Errorf("upload exceeded limit of %d bytes", maxSize)
+	}
+
 	if err = out.Flush(); err != nil {
-		o.Close()
+		cleanup()
+		return "", err
+	}
+
+	if err := o.Close(); err != nil {
 		os.RemoveAll(dir)
 		return "", err
 	}