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Diffstat (limited to 'pkg/sentry/fsimpl/gofer/gofer.go')
-rw-r--r--pkg/sentry/fsimpl/gofer/gofer.go34
1 files changed, 27 insertions, 7 deletions
diff --git a/pkg/sentry/fsimpl/gofer/gofer.go b/pkg/sentry/fsimpl/gofer/gofer.go
index 8e74e60a5..2b83094cd 100644
--- a/pkg/sentry/fsimpl/gofer/gofer.go
+++ b/pkg/sentry/fsimpl/gofer/gofer.go
@@ -110,6 +110,26 @@ type filesystem struct {
syncMu sync.Mutex
syncableDentries map[*dentry]struct{}
specialFileFDs map[*specialFileFD]struct{}
+
+ // syntheticSeq stores a counter to used to generate unique inodeNumber for
+ // synthetic dentries.
+ syntheticSeq uint64
+}
+
+// inodeNumber represents inode number reported in Dirent.Ino. For regular
+// dentries, it comes from QID.Path from the 9P server. Synthetic dentries
+// have have their inodeNumber generated sequentially, with the MSB reserved to
+// prevent conflicts with regular dentries.
+type inodeNumber uint64
+
+// Reserve MSB for synthetic mounts.
+const syntheticInoMask = uint64(1) << 63
+
+func inoFromPath(path uint64) inodeNumber {
+ if path&syntheticInoMask != 0 {
+ log.Warningf("Dropping MSB from ino, collision is possible. Original: %d, new: %d", path, path&^syntheticInoMask)
+ }
+ return inodeNumber(path &^ syntheticInoMask)
}
type filesystemOptions struct {
@@ -585,11 +605,11 @@ type dentry struct {
// Cached metadata; protected by metadataMu and accessed using atomic
// memory operations unless otherwise specified.
metadataMu sync.Mutex
- ino uint64 // immutable
- mode uint32 // type is immutable, perms are mutable
- uid uint32 // auth.KUID, but stored as raw uint32 for sync/atomic
- gid uint32 // auth.KGID, but ...
- blockSize uint32 // 0 if unknown
+ ino inodeNumber // immutable
+ mode uint32 // type is immutable, perms are mutable
+ uid uint32 // auth.KUID, but stored as raw uint32 for sync/atomic
+ gid uint32 // auth.KGID, but ...
+ blockSize uint32 // 0 if unknown
// Timestamps, all nsecs from the Unix epoch.
atime int64
mtime int64
@@ -704,7 +724,7 @@ func (fs *filesystem) newDentry(ctx context.Context, file p9file, qid p9.QID, ma
d := &dentry{
fs: fs,
file: file,
- ino: qid.Path,
+ ino: inoFromPath(qid.Path),
mode: uint32(attr.Mode),
uid: uint32(fs.opts.dfltuid),
gid: uint32(fs.opts.dfltgid),
@@ -846,7 +866,7 @@ func (d *dentry) statTo(stat *linux.Statx) {
stat.UID = atomic.LoadUint32(&d.uid)
stat.GID = atomic.LoadUint32(&d.gid)
stat.Mode = uint16(atomic.LoadUint32(&d.mode))
- stat.Ino = d.ino
+ stat.Ino = uint64(d.ino)
stat.Size = atomic.LoadUint64(&d.size)
// This is consistent with regularFileFD.Seek(), which treats regular files
// as having no holes.