From 11b35d650d279000b2207549100001e089e637c6 Mon Sep 17 00:00:00 2001
From: Jakob Borg <jakob@kastelo.net>
Date: Fri, 16 Dec 2016 11:21:22 +0000
Subject: [PATCH] lib/model: Accept scan requests of paths ending in slash
 (fixes #3804)

GitHub-Pull-Request: https://github.com/syncthing/syncthing/pull/3805
---
 lib/model/model.go      |  5 ++++-
 lib/model/model_test.go | 15 +++++++++++++++
 2 files changed, 19 insertions(+), 1 deletion(-)

diff --git a/lib/model/model.go b/lib/model/model.go
index 66161d3cb..2d536824f 100644
--- a/lib/model/model.go
+++ b/lib/model/model.go
@@ -1690,7 +1690,10 @@ func (m *Model) internalScanFolderSubdirs(folder string, subDirs []string) error
 	for i, sub := range subDirs {
 		sub = osutil.NativeFilename(sub)
 		// We test each path by joining with "root". What we join with is
-		// not relevant, we just want the dotdot escape detection here.
+		// not relevant, we just want the dotdot escape detection here. For
+		// historical reasons we may get paths that end in a slash. We
+		// remove that first to allow the rootedJoinedPath to pass.
+		sub = strings.TrimRight(sub, string(os.PathSeparator))
 		if _, err := rootedJoinedPath("root", sub); err != nil {
 			return errors.New("invalid subpath")
 		}
diff --git a/lib/model/model_test.go b/lib/model/model_test.go
index 17e245c84..27fdaffd7 100644
--- a/lib/model/model_test.go
+++ b/lib/model/model_test.go
@@ -2166,6 +2166,21 @@ func TestIssue3496(t *testing.T) {
 	}
 }
 
+func TestIssue3804(t *testing.T) {
+	dbi := db.OpenMemory()
+	m := NewModel(defaultConfig, protocol.LocalDeviceID, "device", "syncthing", "dev", dbi, nil)
+	m.AddFolder(defaultFolderConfig)
+	m.StartFolder("default")
+	m.ServeBackground()
+	defer m.Stop()
+
+	// Subdirs ending in slash should be accepted
+
+	if err := m.ScanFolderSubdirs("default", []string{"baz/", "foo"}); err != nil {
+		t.Error("Unexpected error:", err)
+	}
+}
+
 func TestRootedJoinedPath(t *testing.T) {
 	type testcase struct {
 		root   string