diff options
Diffstat (limited to 'pkg/sentry/fsimpl/gofer/filesystem.go')
| -rw-r--r-- | pkg/sentry/fsimpl/gofer/filesystem.go | 14 |
1 files changed, 12 insertions, 2 deletions
diff --git a/pkg/sentry/fsimpl/gofer/filesystem.go b/pkg/sentry/fsimpl/gofer/filesystem.go index 91d5dc174..8f95473b6 100644 --- a/pkg/sentry/fsimpl/gofer/filesystem.go +++ b/pkg/sentry/fsimpl/gofer/filesystem.go @@ -36,16 +36,26 @@ import ( // Sync implements vfs.FilesystemImpl.Sync. func (fs *filesystem) Sync(ctx context.Context) error { // Snapshot current syncable dentries and special file FDs. + fs.renameMu.RLock() fs.syncMu.Lock() ds := make([]*dentry, 0, len(fs.syncableDentries)) for d := range fs.syncableDentries { + // It's safe to use IncRef here even though fs.syncableDentries doesn't + // hold references since we hold fs.renameMu. Note that we can't use + // TryIncRef since cached dentries at zero references should still be + // synced. d.IncRef() ds = append(ds, d) } + fs.renameMu.RUnlock() sffds := make([]*specialFileFD, 0, len(fs.specialFileFDs)) for sffd := range fs.specialFileFDs { - sffd.vfsfd.IncRef() - sffds = append(sffds, sffd) + // As above, fs.specialFileFDs doesn't hold references. However, unlike + // dentries, an FD that has reached zero references can't be + // resurrected, so we can use TryIncRef. + if sffd.vfsfd.TryIncRef() { + sffds = append(sffds, sffd) + } } fs.syncMu.Unlock() |