diff options
Diffstat (limited to 'pkg/sentry/fs/ext/ext.go')
| -rw-r--r-- | pkg/sentry/fs/ext/ext.go | 23 |
1 files changed, 11 insertions, 12 deletions
diff --git a/pkg/sentry/fs/ext/ext.go b/pkg/sentry/fs/ext/ext.go index 2380f15da..d303dd122 100644 --- a/pkg/sentry/fs/ext/ext.go +++ b/pkg/sentry/fs/ext/ext.go @@ -19,9 +19,9 @@ import ( "errors" "fmt" "io" - "os" "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/fd" "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/fs/ext/disklayout" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" @@ -35,11 +35,11 @@ type filesystemType struct{} // Compiles only if filesystemType implements vfs.FilesystemType. var _ vfs.FilesystemType = (*filesystemType)(nil) -// getDeviceFd returns the read seeker to the underlying device. +// getDeviceFd returns an io.ReaderAt to the underlying device. // Currently there are two ways of mounting an ext(2/3/4) fs: // 1. Specify a mount with our internal special MountType in the OCI spec. // 2. Expose the device to the container and mount it from application layer. -func getDeviceFd(source string, opts vfs.NewFilesystemOptions) (io.ReadSeeker, error) { +func getDeviceFd(source string, opts vfs.NewFilesystemOptions) (io.ReaderAt, error) { if opts.InternalData == nil { // User mount call. // TODO(b/134676337): Open the device specified by `source` and return that. @@ -47,20 +47,19 @@ func getDeviceFd(source string, opts vfs.NewFilesystemOptions) (io.ReadSeeker, e } // NewFilesystem call originated from within the sentry. - fd, ok := opts.InternalData.(uintptr) + devFd, ok := opts.InternalData.(int) if !ok { - return nil, errors.New("internal data for ext fs must be a uintptr containing the file descriptor to device") + return nil, errors.New("internal data for ext fs must be an int containing the file descriptor to device") } - // We do not close this file because that would close the underlying device - // file descriptor (which is required for reading the fs from disk). - // TODO(b/134676337): Use pkg/fd instead. - deviceFile := os.NewFile(fd, source) - if deviceFile == nil { - return nil, fmt.Errorf("ext4 device file descriptor is not valid: %d", fd) + if devFd < 0 { + return nil, fmt.Errorf("ext device file descriptor is not valid: %d", devFd) } - return deviceFile, nil + // The fd.ReadWriter returned from fd.NewReadWriter() does not take ownership + // of the file descriptor and hence will not close it when it is garbage + // collected. + return fd.NewReadWriter(devFd), nil } // NewFilesystem implements vfs.FilesystemType.NewFilesystem. |