Use new reference count utility throughout gvisor.

This uses the refs_vfs2 template in vfs2 as well as objects common to vfs1 and
vfs2. Note that vfs1-only refcounts are not replaced, since vfs1 will be deleted
soon anyway.

The following structs now use the new tool, with leak check enabled:
devpts:rootInode
fuse:inode
kernfs:Dentry
kernfs:dir
kernfs:readonlyDir
kernfs:StaticDirectory
proc:fdDirInode
proc:fdInfoDirInode
proc:subtasksInode
proc:taskInode
proc:tasksInode
vfs:FileDescription
vfs:MountNamespace
vfs:Filesystem
sys:dir
kernel:FSContext
kernel:ProcessGroup
kernel:Session
shm:Shm
mm:aioMappable
mm:SpecialMappable
transport:queue

And the following use the template, but because they currently are not leak
checked, a TODO is left instead of enabling leak check in this patch:
kernel:FDTable
tun:tunEndpoint

Updates #1486.

PiperOrigin-RevId: 328460377

1 files changed, 12 insertions, 0 deletions

diff --git a/pkg/sentry/fsimpl/kernfs/kernfs_test.go b/pkg/sentry/fsimpl/kernfs/kernfs_test.go
index e5c28c0e4..e376d1736 100644
--- a/pkg/sentry/fsimpl/kernfs/kernfs_test.go
+++ b/pkg/sentry/fsimpl/kernfs/kernfs_test.go
@@ -96,6 +96,7 @@ func (*attrs) SetStat(context.Context, *vfs.Filesystem, *auth.Credentials, vfs.S
 }
 
 type readonlyDir struct {
+	readonlyDirRefs
 	attrs
 	kernfs.InodeNotSymlink
 	kernfs.InodeNoDynamicLookup
@@ -111,6 +112,7 @@ func (fs *filesystem) newReadonlyDir(creds *auth.Credentials, mode linux.FileMod
 	dir := &readonlyDir{}
 	dir.attrs.Init(creds, 0 /* devMajor */, 0 /* devMinor */, fs.NextIno(), linux.ModeDirectory|mode)
 	dir.OrderedChildren.Init(kernfs.OrderedChildrenOptions{})
+	dir.EnableLeakCheck()
 	dir.dentry.Init(dir)
 
 	dir.IncLinks(dir.OrderedChildren.Populate(&dir.dentry, contents))
@@ -128,7 +130,12 @@ func (d *readonlyDir) Open(ctx context.Context, rp *vfs.ResolvingPath, vfsd *vfs
 	return fd.VFSFileDescription(), nil
 }
 
+func (d *readonlyDir) DecRef(context.Context) {
+	d.readonlyDirRefs.DecRef(d.Destroy)
+}
+
 type dir struct {
+	dirRefs
 	attrs
 	kernfs.InodeNotSymlink
 	kernfs.InodeNoDynamicLookup
@@ -145,6 +152,7 @@ func (fs *filesystem) newDir(creds *auth.Credentials, mode linux.FileMode, conte
 	dir.fs = fs
 	dir.attrs.Init(creds, 0 /* devMajor */, 0 /* devMinor */, fs.NextIno(), linux.ModeDirectory|mode)
 	dir.OrderedChildren.Init(kernfs.OrderedChildrenOptions{Writable: true})
+	dir.EnableLeakCheck()
 	dir.dentry.Init(dir)
 
 	dir.IncLinks(dir.OrderedChildren.Populate(&dir.dentry, contents))
@@ -162,6 +170,10 @@ func (d *dir) Open(ctx context.Context, rp *vfs.ResolvingPath, vfsd *vfs.Dentry,
 	return fd.VFSFileDescription(), nil
 }
 
+func (d *dir) DecRef(context.Context) {
+	d.dirRefs.DecRef(d.Destroy)
+}
+
 func (d *dir) NewDir(ctx context.Context, name string, opts vfs.MkdirOptions) (*vfs.Dentry, error) {
 	creds := auth.CredentialsFromContext(ctx)
 	dir := d.fs.newDir(creds, opts.Mode, nil)