diff options
| author | Ayush Ranjan <ayushranjan@google.com> | 2021-10-08 14:46:16 -0700 |
|---|---|---|
| committer | gVisor bot <gvisor-bot@google.com> | 2021-10-08 14:48:35 -0700 |
| commit | da41ecc5be8a25d116b520da2c3d424ef488b159 (patch) | |
| tree | 52166d53f4474cf834c3408e06bdf85194ccf7fe /pkg/sentry/fsimpl/gofer/gofer.go | |
| parent | e44b100654ca639d11221e547384f699e461296d (diff) | |
Disallow "trusted" namespace xattr in VFS2 gofer client.
Allowing this namespace makes way for a lot of GetXattr RPCs to the gofer
process when the gofer filesystem is the lower layer of an overlay.
The overlay filesystem aggressively queries for "trusted.overlay.opaque" which
in practice is never found in the lower layer gofer. But leads to a lot of
wasted work.
A consequence is that mutable gofer upper layer is not supported anymore but
that is still consistent with VFS1. We can revisit when need arises.
PiperOrigin-RevId: 401860585
Diffstat (limited to 'pkg/sentry/fsimpl/gofer/gofer.go')
| -rw-r--r-- | pkg/sentry/fsimpl/gofer/gofer.go | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/pkg/sentry/fsimpl/gofer/gofer.go b/pkg/sentry/fsimpl/gofer/gofer.go index 7bef8242f..2dd9226c1 100644 --- a/pkg/sentry/fsimpl/gofer/gofer.go +++ b/pkg/sentry/fsimpl/gofer/gofer.go @@ -1595,7 +1595,10 @@ func (d *dentry) checkXattrPermissions(creds *auth.Credentials, name string, ats // (b/148380782). Allow all other extended attributes to be passed through // to the remote filesystem. This is inconsistent with Linux's 9p client, // but consistent with other filesystems (e.g. FUSE). - if strings.HasPrefix(name, linux.XATTR_SECURITY_PREFIX) || strings.HasPrefix(name, linux.XATTR_SYSTEM_PREFIX) { + // + // NOTE(b/202533394): Also disallow "trusted" namespace for now. This is + // consistent with the VFS1 gofer client. + if strings.HasPrefix(name, linux.XATTR_SECURITY_PREFIX) || strings.HasPrefix(name, linux.XATTR_SYSTEM_PREFIX) || strings.HasPrefix(name, linux.XATTR_TRUSTED_PREFIX) { return linuxerr.EOPNOTSUPP } mode := linux.FileMode(atomic.LoadUint32(&d.mode)) |