diff options
| author | Kevin Krakauer <krakauer@google.com> | 2021-03-23 15:40:17 -0700 |
|---|---|---|
| committer | gVisor bot <gvisor-bot@google.com> | 2021-03-23 15:42:12 -0700 |
| commit | 92374e51976c8a47e4705943f73cecbc6a27073b (patch) | |
| tree | 5f267314a82b8dbdc4638c8eb1e2c5b062890ca0 /pkg/sentry/fsimpl/gofer/regular_file.go | |
| parent | acb4c62885629d6d3ee977b93c27282abed0b33f (diff) | |
setgid directory support in goferfs
Also adds support for clearing the setuid bit when appropriate (writing,
truncating, changing size, changing UID, or changing GID).
VFS2 only.
PiperOrigin-RevId: 364661835
Diffstat (limited to 'pkg/sentry/fsimpl/gofer/regular_file.go')
| -rw-r--r-- | pkg/sentry/fsimpl/gofer/regular_file.go | 14 |
1 files changed, 14 insertions, 0 deletions
diff --git a/pkg/sentry/fsimpl/gofer/regular_file.go b/pkg/sentry/fsimpl/gofer/regular_file.go index 283b220bb..4f1ad0c88 100644 --- a/pkg/sentry/fsimpl/gofer/regular_file.go +++ b/pkg/sentry/fsimpl/gofer/regular_file.go @@ -266,6 +266,20 @@ func (fd *regularFileFD) pwrite(ctx context.Context, src usermem.IOSequence, off return 0, offset, err } } + + // As with Linux, writing clears the setuid and setgid bits. + if n > 0 { + oldMode := atomic.LoadUint32(&d.mode) + // If setuid or setgid were set, update d.mode and propagate + // changes to the host. + if newMode := vfs.ClearSUIDAndSGID(oldMode); newMode != oldMode { + atomic.StoreUint32(&d.mode, newMode) + if err := d.file.setAttr(ctx, p9.SetAttrMask{Permissions: true}, p9.SetAttr{Permissions: p9.FileMode(newMode)}); err != nil { + return 0, offset, err + } + } + } + return n, offset + n, nil } |