diff options
author | gVisor bot <gvisor-bot@google.com> | 2020-08-21 21:33:02 +0000 |
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committer | gVisor bot <gvisor-bot@google.com> | 2020-08-21 21:33:02 +0000 |
commit | 1b1de470fa39ce55df3559c2e4901a74d3084f13 (patch) | |
tree | bfffb7fbe247127b9a28c0f83f5689a601ef80ad /pkg/sentry/vfs | |
parent | bb26261d7bf19ace95bad78a7e5b88df75618997 (diff) | |
parent | 5ec3d4ed3e3cda8944e851ef845f6d275999858a (diff) |
Merge release-20200810.0-83-g5ec3d4ed3 (automated)
Diffstat (limited to 'pkg/sentry/vfs')
-rw-r--r-- | pkg/sentry/vfs/context.go | 24 | ||||
-rw-r--r-- | pkg/sentry/vfs/mount.go | 19 |
2 files changed, 39 insertions, 4 deletions
diff --git a/pkg/sentry/vfs/context.go b/pkg/sentry/vfs/context.go index c9e724fef..97018651f 100644 --- a/pkg/sentry/vfs/context.go +++ b/pkg/sentry/vfs/context.go @@ -40,6 +40,30 @@ func MountNamespaceFromContext(ctx context.Context) *MountNamespace { return nil } +type mountNamespaceContext struct { + context.Context + mntns *MountNamespace +} + +// Value implements Context.Value. +func (mc mountNamespaceContext) Value(key interface{}) interface{} { + switch key { + case CtxMountNamespace: + mc.mntns.IncRef() + return mc.mntns + default: + return mc.Context.Value(key) + } +} + +// WithMountNamespace returns a copy of ctx with the given MountNamespace. +func WithMountNamespace(ctx context.Context, mntns *MountNamespace) context.Context { + return &mountNamespaceContext{ + Context: ctx, + mntns: mntns, + } +} + // RootFromContext returns the VFS root used by ctx. It takes a reference on // the returned VirtualDentry. If ctx does not have a specific VFS root, // RootFromContext returns a zero-value VirtualDentry. diff --git a/pkg/sentry/vfs/mount.go b/pkg/sentry/vfs/mount.go index 714af6907..09fea3628 100644 --- a/pkg/sentry/vfs/mount.go +++ b/pkg/sentry/vfs/mount.go @@ -263,16 +263,20 @@ func (vfs *VirtualFilesystem) ConnectMountAt(ctx context.Context, creds *auth.Cr } // MountAt creates and mounts a Filesystem configured by the given arguments. -func (vfs *VirtualFilesystem) MountAt(ctx context.Context, creds *auth.Credentials, source string, target *PathOperation, fsTypeName string, opts *MountOptions) error { +// The VirtualFilesystem will hold a reference to the Mount until it is unmounted. +// +// This method returns the mounted Mount without a reference, for convenience +// during VFS setup when there is no chance of racing with unmount. +func (vfs *VirtualFilesystem) MountAt(ctx context.Context, creds *auth.Credentials, source string, target *PathOperation, fsTypeName string, opts *MountOptions) (*Mount, error) { mnt, err := vfs.MountDisconnected(ctx, creds, source, fsTypeName, opts) if err != nil { - return err + return nil, err } defer mnt.DecRef(ctx) if err := vfs.ConnectMountAt(ctx, creds, mnt, target); err != nil { - return err + return nil, err } - return nil + return mnt, nil } // UmountAt removes the Mount at the given path. @@ -657,6 +661,13 @@ retryFirst: return VirtualDentry{mnt, d} } +// SetMountReadOnly sets the mount as ReadOnly. +func (vfs *VirtualFilesystem) SetMountReadOnly(mnt *Mount, ro bool) error { + vfs.mountMu.Lock() + defer vfs.mountMu.Unlock() + return mnt.setReadOnlyLocked(ro) +} + // CheckBeginWrite increments the counter of in-progress write operations on // mnt. If mnt is mounted MS_RDONLY, CheckBeginWrite does nothing and returns // EROFS. |