Merge release-20211019.0-44-g7b8f19dc7 (automated)

7 files changed, 11 insertions, 42 deletions

diff --git a/pkg/sentry/fsimpl/mqfs/registry.go b/pkg/sentry/fsimpl/mqfs/registry.go
index e470ffadc..69182965c 100644
--- a/pkg/sentry/fsimpl/mqfs/registry.go
+++ b/pkg/sentry/fsimpl/mqfs/registry.go
@@ -71,10 +71,7 @@ func NewRegistryImpl(ctx context.Context, vfsObj *vfs.VirtualFilesystem, creds *
 	var dentry kernfs.Dentry
 	dentry.InitRoot(&fs.Filesystem, fs.newRootInode(ctx, creds))
 
-	mount, err := vfsObj.NewDisconnectedMount(vfsfs, dentry.VFSDentry(), &vfs.MountOptions{})
-	if err != nil {
-		return nil, err
-	}
+	mount := vfsObj.NewDisconnectedMount(vfsfs, dentry.VFSDentry(), &vfs.MountOptions{})
 
 	return &RegistryImpl{
 		root:  &dentry,
diff --git a/pkg/sentry/fsimpl/overlay/overlay.go b/pkg/sentry/fsimpl/overlay/overlay.go
index 46d9f1f1d..327c37477 100644
--- a/pkg/sentry/fsimpl/overlay/overlay.go
+++ b/pkg/sentry/fsimpl/overlay/overlay.go
@@ -314,10 +314,7 @@ func clonePrivateMount(vfsObj *vfs.VirtualFilesystem, vd vfs.VirtualDentry, forc
 	if forceReadOnly {
 		opts.ReadOnly = true
 	}
-	newmnt, err := vfsObj.NewDisconnectedMount(oldmnt.Filesystem(), vd.Dentry(), &opts)
-	if err != nil {
-		return vfs.VirtualDentry{}, err
-	}
+	newmnt := vfsObj.NewDisconnectedMount(oldmnt.Filesystem(), vd.Dentry(), &opts)
 	// Take a reference on the dentry which will be owned by the returned
 	// VirtualDentry.
 	d := vd.Dentry()
diff --git a/pkg/sentry/kernel/kernel.go b/pkg/sentry/kernel/kernel.go
index d4851ccda..83299a9fb 100644
--- a/pkg/sentry/kernel/kernel.go
+++ b/pkg/sentry/kernel/kernel.go
@@ -418,10 +418,7 @@ func (k *Kernel) Init(args InitKernelArgs) error {
 			return fmt.Errorf("failed to create pipefs filesystem: %v", err)
 		}
 		defer pipeFilesystem.DecRef(ctx)
-		pipeMount, err := k.vfs.NewDisconnectedMount(pipeFilesystem, nil, &vfs.MountOptions{})
-		if err != nil {
-			return fmt.Errorf("failed to create pipefs mount: %v", err)
-		}
+		pipeMount := k.vfs.NewDisconnectedMount(pipeFilesystem, nil, &vfs.MountOptions{})
 		k.pipeMount = pipeMount
 
 		tmpfsFilesystem, tmpfsRoot, err := tmpfs.NewFilesystem(ctx, &k.vfs, auth.NewRootCredentials(k.rootUserNamespace))
@@ -430,22 +427,14 @@ func (k *Kernel) Init(args InitKernelArgs) error {
 		}
 		defer tmpfsFilesystem.DecRef(ctx)
 		defer tmpfsRoot.DecRef(ctx)
-		shmMount, err := k.vfs.NewDisconnectedMount(tmpfsFilesystem, tmpfsRoot, &vfs.MountOptions{})
-		if err != nil {
-			return fmt.Errorf("failed to create tmpfs mount: %v", err)
-		}
-		k.shmMount = shmMount
+		k.shmMount = k.vfs.NewDisconnectedMount(tmpfsFilesystem, tmpfsRoot, &vfs.MountOptions{})
 
 		socketFilesystem, err := sockfs.NewFilesystem(&k.vfs)
 		if err != nil {
 			return fmt.Errorf("failed to create sockfs filesystem: %v", err)
 		}
 		defer socketFilesystem.DecRef(ctx)
-		socketMount, err := k.vfs.NewDisconnectedMount(socketFilesystem, nil, &vfs.MountOptions{})
-		if err != nil {
-			return fmt.Errorf("failed to create sockfs mount: %v", err)
-		}
-		k.socketMount = socketMount
+		k.socketMount = k.vfs.NewDisconnectedMount(socketFilesystem, nil, &vfs.MountOptions{})
 
 		k.socketsVFS2 = make(map[*vfs.FileDescription]*SocketRecord)
 
diff --git a/pkg/sentry/vfs/mount.go b/pkg/sentry/vfs/mount.go
index 05a416775..9ab9a8fca 100644
--- a/pkg/sentry/vfs/mount.go
+++ b/pkg/sentry/vfs/mount.go
@@ -178,12 +178,12 @@ func (vfs *VirtualFilesystem) NewMountNamespace(ctx context.Context, creds *auth
 // (which may be nil). The new Mount is not associated with any MountNamespace
 // and is not connected to any other Mounts. References are taken on fs and
 // root.
-func (vfs *VirtualFilesystem) NewDisconnectedMount(fs *Filesystem, root *Dentry, opts *MountOptions) (*Mount, error) {
+func (vfs *VirtualFilesystem) NewDisconnectedMount(fs *Filesystem, root *Dentry, opts *MountOptions) *Mount {
 	fs.IncRef()
 	if root != nil {
 		root.IncRef()
 	}
-	return newMount(vfs, fs, root, nil /* mntns */, opts), nil
+	return newMount(vfs, fs, root, nil /* mntns */, opts)
 }
 
 // MountDisconnected creates a Filesystem configured by the given arguments,
@@ -201,9 +201,7 @@ func (vfs *VirtualFilesystem) MountDisconnected(ctx context.Context, creds *auth
 	if err != nil {
 		return nil, err
 	}
-	defer root.DecRef(ctx)
-	defer fs.DecRef(ctx)
-	return vfs.NewDisconnectedMount(fs, root, opts)
+	return newMount(vfs, fs, root, nil /* mntns */, opts), nil
 }
 
 // ConnectMountAt connects mnt at the path represented by target.
diff --git a/pkg/sentry/vfs/vfs.go b/pkg/sentry/vfs/vfs.go
index 1b2a668c0..9c1ee549a 100644
--- a/pkg/sentry/vfs/vfs.go
+++ b/pkg/sentry/vfs/vfs.go
@@ -150,12 +150,7 @@ func (vfs *VirtualFilesystem) Init(ctx context.Context) error {
 	}
 	anonfs.vfsfs.Init(vfs, &anonFilesystemType{}, &anonfs)
 	defer anonfs.vfsfs.DecRef(ctx)
-	anonMount, err := vfs.NewDisconnectedMount(&anonfs.vfsfs, nil, &MountOptions{})
-	if err != nil {
-		// We should not be passing any MountOptions that would cause
-		// construction of this mount to fail.
-		panic(fmt.Sprintf("VirtualFilesystem.Init: anonfs mount failed: %v", err))
-	}
+	anonMount := vfs.NewDisconnectedMount(&anonfs.vfsfs, nil, &MountOptions{})
 	vfs.anonMount = anonMount
 
 	return nil
diff --git a/runsc/boot/loader.go b/runsc/boot/loader.go
index dbb02fdf4..247f0d54a 100644
--- a/runsc/boot/loader.go
+++ b/runsc/boot/loader.go
@@ -411,11 +411,7 @@ func New(args Args) (*Loader, error) {
 			return nil, fmt.Errorf("failed to create hostfs filesystem: %w", err)
 		}
 		defer hostFilesystem.DecRef(k.SupervisorContext())
-		hostMount, err := k.VFS().NewDisconnectedMount(hostFilesystem, nil, &vfs.MountOptions{})
-		if err != nil {
-			return nil, fmt.Errorf("failed to create hostfs mount: %w", err)
-		}
-		k.SetHostMount(hostMount)
+		k.SetHostMount(k.VFS().NewDisconnectedMount(hostFilesystem, nil, &vfs.MountOptions{}))
 	}
 
 	eid := execID{cid: args.ID}
diff --git a/runsc/boot/vfs.go b/runsc/boot/vfs.go
index 9f0d1ae36..4d0cfc94a 100644
--- a/runsc/boot/vfs.go
+++ b/runsc/boot/vfs.go
@@ -769,10 +769,7 @@ func (c *containerMounter) mountSharedSubmountVFS2(ctx context.Context, conf *co
 	if err != nil {
 		return nil, err
 	}
-	newMnt, err := c.k.VFS().NewDisconnectedMount(source.vfsMount.Filesystem(), source.vfsMount.Root(), opts)
-	if err != nil {
-		return nil, err
-	}
+	newMnt := c.k.VFS().NewDisconnectedMount(source.vfsMount.Filesystem(), source.vfsMount.Root(), opts)
 	defer newMnt.DecRef(ctx)
 
 	root := mns.Root()