From f67c5a2fd67459b219cc8c455e72c9ebbd37cf81 Mon Sep 17 00:00:00 2001 From: Jakob Borg Date: Sat, 17 Dec 2016 19:48:33 +0000 Subject: [PATCH] lib/model: Don't send symlinks to old devices that can't handle them (fixes #3802) GitHub-Pull-Request: https://github.com/syncthing/syncthing/pull/3811 --- lib/model/model.go | 28 +++++++++++++++++++++++----- 1 file changed, 23 insertions(+), 5 deletions(-) diff --git a/lib/model/model.go b/lib/model/model.go index 6472c4d79..5d3097ff6 100644 --- a/lib/model/model.go +++ b/lib/model/model.go @@ -35,6 +35,7 @@ import ( "github.com/syncthing/syncthing/lib/stats" "github.com/syncthing/syncthing/lib/symlinks" "github.com/syncthing/syncthing/lib/sync" + "github.com/syncthing/syncthing/lib/upgrade" "github.com/syncthing/syncthing/lib/versioner" "github.com/thejerf/suture" ) @@ -764,6 +765,7 @@ func (m *Model) ClusterConfig(deviceID protocol.DeviceID, cm protocol.ClusterCon m.pmut.RLock() conn, ok := m.conn[deviceID] + hello := m.helloMessages[deviceID] m.pmut.RUnlock() if !ok { panic("bug: ClusterConfig called on closed or nonexistent connection") @@ -771,6 +773,14 @@ func (m *Model) ClusterConfig(deviceID protocol.DeviceID, cm protocol.ClusterCon dbLocation := filepath.Dir(m.db.Location()) + // See issue #3802 - in short, we can't send modern symlink entries to older + // clients. + dropSymlinks := false + if hello.ClientName == m.clientName && upgrade.CompareVersions(hello.ClientVersion, "v0.14.14") < 0 { + l.Warnln("Not sending symlinks to old client", deviceID, "- please upgrade to v0.14.14 or newer") + dropSymlinks = true + } + m.fmut.Lock() for _, folder := range cm.Folders { if !m.folderSharedWithLocked(folder.ID, deviceID) { @@ -857,7 +867,7 @@ func (m *Model) ClusterConfig(deviceID protocol.DeviceID, cm protocol.ClusterCon } } - go sendIndexes(conn, folder.ID, fs, m.folderIgnores[folder.ID], startSequence, dbLocation) + go sendIndexes(conn, folder.ID, fs, m.folderIgnores[folder.ID], startSequence, dbLocation, dropSymlinks) } // This breaks if we send multiple CM messages during the same connection. @@ -1434,7 +1444,7 @@ func (m *Model) receivedFile(folder string, file protocol.FileInfo) { m.folderStatRef(folder).ReceivedFile(file.Name, file.IsDeleted()) } -func sendIndexes(conn protocol.Connection, folder string, fs *db.FileSet, ignores *ignore.Matcher, startSequence int64, dbLocation string) { +func sendIndexes(conn protocol.Connection, folder string, fs *db.FileSet, ignores *ignore.Matcher, startSequence int64, dbLocation string, dropSymlinks bool) { deviceID := conn.ID() name := conn.Name() var err error @@ -1442,7 +1452,7 @@ func sendIndexes(conn protocol.Connection, folder string, fs *db.FileSet, ignore l.Debugf("sendIndexes for %s-%s/%q starting (slv=%d)", deviceID, name, folder, startSequence) defer l.Debugf("sendIndexes for %s-%s/%q exiting: %v", deviceID, name, folder, err) - minSequence, err := sendIndexTo(startSequence, conn, folder, fs, ignores, dbLocation) + minSequence, err := sendIndexTo(startSequence, conn, folder, fs, ignores, dbLocation, dropSymlinks) // Subscribe to LocalIndexUpdated (we have new information to send) and // DeviceDisconnected (it might be us who disconnected, so we should @@ -1465,7 +1475,7 @@ func sendIndexes(conn protocol.Connection, folder string, fs *db.FileSet, ignore continue } - minSequence, err = sendIndexTo(minSequence, conn, folder, fs, ignores, dbLocation) + minSequence, err = sendIndexTo(minSequence, conn, folder, fs, ignores, dbLocation, dropSymlinks) // Wait a short amount of time before entering the next loop. If there // are continuous changes happening to the local index, this gives us @@ -1474,7 +1484,7 @@ func sendIndexes(conn protocol.Connection, folder string, fs *db.FileSet, ignore } } -func sendIndexTo(minSequence int64, conn protocol.Connection, folder string, fs *db.FileSet, ignores *ignore.Matcher, dbLocation string) (int64, error) { +func sendIndexTo(minSequence int64, conn protocol.Connection, folder string, fs *db.FileSet, ignores *ignore.Matcher, dbLocation string, dropSymlinks bool) (int64, error) { deviceID := conn.ID() name := conn.Name() batch := make([]protocol.FileInfo, 0, indexBatchSize) @@ -1496,6 +1506,14 @@ func sendIndexTo(minSequence int64, conn protocol.Connection, folder string, fs maxSequence = f.Sequence } + if dropSymlinks && f.IsSymlink() { + // Do not send index entries with symlinks to clients that can't + // handle it. Fixes issue #3802. Once both sides are upgraded, a + // rescan (i.e., change) of the symlink is required for it to + // sync again, due to delta indexes. + return true + } + sorter.Append(f) return true })