From 02d552d07c4415978d2ce418fb16baf238d0ff78 Mon Sep 17 00:00:00 2001 From: Dean Deng Date: Sat, 27 Jun 2020 14:38:20 -0700 Subject: Support sticky bit in vfs2. Updates #2923. PiperOrigin-RevId: 318648128 --- pkg/sentry/fsimpl/tmpfs/directory.go | 4 ++++ pkg/sentry/fsimpl/tmpfs/filesystem.go | 9 +++++++++ 2 files changed, 13 insertions(+) (limited to 'pkg/sentry/fsimpl/tmpfs') diff --git a/pkg/sentry/fsimpl/tmpfs/directory.go b/pkg/sentry/fsimpl/tmpfs/directory.go index b172abc15..0a1ad4765 100644 --- a/pkg/sentry/fsimpl/tmpfs/directory.go +++ b/pkg/sentry/fsimpl/tmpfs/directory.go @@ -81,6 +81,10 @@ func (dir *directory) removeChildLocked(child *dentry) { dir.iterMu.Unlock() } +func (dir *directory) mayDelete(creds *auth.Credentials, child *dentry) error { + return vfs.CheckDeleteSticky(creds, linux.FileMode(atomic.LoadUint32(&dir.inode.mode)), auth.KUID(atomic.LoadUint32(&child.inode.uid))) +} + type directoryFD struct { fileDescription vfs.DirectoryFileDescriptionDefaultImpl diff --git a/pkg/sentry/fsimpl/tmpfs/filesystem.go b/pkg/sentry/fsimpl/tmpfs/filesystem.go index f766b7ce2..71ac7b8e6 100644 --- a/pkg/sentry/fsimpl/tmpfs/filesystem.go +++ b/pkg/sentry/fsimpl/tmpfs/filesystem.go @@ -492,6 +492,9 @@ func (fs *filesystem) RenameAt(ctx context.Context, rp *vfs.ResolvingPath, oldPa if !ok { return syserror.ENOENT } + if err := oldParentDir.mayDelete(rp.Credentials(), renamed); err != nil { + return err + } // Note that we don't need to call rp.CheckMount(), since if renamed is a // mount point then we want to rename the mount point, not anything in the // mounted filesystem. @@ -606,6 +609,9 @@ func (fs *filesystem) RmdirAt(ctx context.Context, rp *vfs.ResolvingPath) error if !ok { return syserror.ENOENT } + if err := parentDir.mayDelete(rp.Credentials(), child); err != nil { + return err + } childDir, ok := child.inode.impl.(*directory) if !ok { return syserror.ENOTDIR @@ -716,6 +722,9 @@ func (fs *filesystem) UnlinkAt(ctx context.Context, rp *vfs.ResolvingPath) error if !ok { return syserror.ENOENT } + if err := parentDir.mayDelete(rp.Credentials(), child); err != nil { + return err + } if child.inode.isDir() { return syserror.EISDIR } -- cgit v1.2.3