diff options
Diffstat (limited to 'pkg/sentry/vfs')
| -rw-r--r-- | pkg/sentry/vfs/file_description.go | 15 | ||||
| -rw-r--r-- | pkg/sentry/vfs/filesystem.go | 3 | ||||
| -rw-r--r-- | pkg/sentry/vfs/options.go | 19 |
3 files changed, 29 insertions, 8 deletions
diff --git a/pkg/sentry/vfs/file_description.go b/pkg/sentry/vfs/file_description.go index 15cc091e2..418d69b96 100644 --- a/pkg/sentry/vfs/file_description.go +++ b/pkg/sentry/vfs/file_description.go @@ -111,10 +111,10 @@ type FileDescriptionOptions struct { } // Init must be called before first use of fd. If it succeeds, it takes -// references on mnt and d. statusFlags is the initial file description status -// flags, which is usually the full set of flags passed to open(2). -func (fd *FileDescription) Init(impl FileDescriptionImpl, statusFlags uint32, mnt *Mount, d *Dentry, opts *FileDescriptionOptions) error { - writable := MayWriteFileWithOpenFlags(statusFlags) +// references on mnt and d. flags is the initial file description flags, which +// is usually the full set of flags passed to open(2). +func (fd *FileDescription) Init(impl FileDescriptionImpl, flags uint32, mnt *Mount, d *Dentry, opts *FileDescriptionOptions) error { + writable := MayWriteFileWithOpenFlags(flags) if writable { if err := mnt.CheckBeginWrite(); err != nil { return err @@ -122,7 +122,10 @@ func (fd *FileDescription) Init(impl FileDescriptionImpl, statusFlags uint32, mn } fd.refs = 1 - fd.statusFlags = statusFlags + + // Remove "file creation flags" to mirror the behavior from file.f_flags in + // fs/open.c:do_dentry_open + fd.statusFlags = flags &^ (linux.O_CREAT | linux.O_EXCL | linux.O_NOCTTY | linux.O_TRUNC) fd.vd = VirtualDentry{ mount: mnt, dentry: d, @@ -130,7 +133,7 @@ func (fd *FileDescription) Init(impl FileDescriptionImpl, statusFlags uint32, mn mnt.IncRef() d.IncRef() fd.opts = *opts - fd.readable = MayReadFileWithOpenFlags(statusFlags) + fd.readable = MayReadFileWithOpenFlags(flags) fd.writable = writable fd.impl = impl return nil diff --git a/pkg/sentry/vfs/filesystem.go b/pkg/sentry/vfs/filesystem.go index 74577bc2f..20e5bb072 100644 --- a/pkg/sentry/vfs/filesystem.go +++ b/pkg/sentry/vfs/filesystem.go @@ -443,8 +443,7 @@ type FilesystemImpl interface { // Errors: // // - If extended attributes are not supported by the filesystem, - // ListxattrAt returns nil. (See FileDescription.Listxattr for an - // explanation.) + // ListxattrAt returns ENOTSUP. // // - If the size of the list (including a NUL terminating byte after every // entry) would exceed size, ERANGE may be returned. Note that diff --git a/pkg/sentry/vfs/options.go b/pkg/sentry/vfs/options.go index 534528ce6..022bac127 100644 --- a/pkg/sentry/vfs/options.go +++ b/pkg/sentry/vfs/options.go @@ -33,6 +33,25 @@ type GetDentryOptions struct { type MkdirOptions struct { // Mode is the file mode bits for the created directory. Mode linux.FileMode + + // If ForSyntheticMountpoint is true, FilesystemImpl.MkdirAt() may create + // the given directory in memory only (as opposed to persistent storage). + // The created directory should be able to support the creation of + // subdirectories with ForSyntheticMountpoint == true. It does not need to + // support the creation of subdirectories with ForSyntheticMountpoint == + // false, or files of other types. + // + // FilesystemImpls are permitted to ignore the ForSyntheticMountpoint + // option. + // + // The ForSyntheticMountpoint option exists because, unlike mount(2), the + // OCI Runtime Specification permits the specification of mount points that + // do not exist, under the expectation that container runtimes will create + // them. (More accurately, the OCI Runtime Specification completely fails + // to document this feature, but it's implemented by runc.) + // ForSyntheticMountpoint allows such mount points to be created even when + // the underlying persistent filesystem is immutable. + ForSyntheticMountpoint bool } // MknodOptions contains options to VirtualFilesystem.MknodAt() and |