diff options
| author | Dean Deng <deandeng@google.com> | 2020-06-17 11:32:23 -0700 |
|---|---|---|
| committer | gVisor bot <gvisor-bot@google.com> | 2020-06-17 11:34:06 -0700 |
| commit | e5d97cbcc1e64185b8fab1cf563c8754edd2e52e (patch) | |
| tree | c621fe72067125d2b5c34bfd18cd52a428cd924b | |
| parent | 50afec55c75dfd5bb88d100f77e17048dfbb3322 (diff) | |
Refactor host.canMap.
Simplify the canMap check. We do not have plans to allow mmap for anything
beyond regular files, so we can just inline canMap() as a simple file mode
check.
Updates #1672.
PiperOrigin-RevId: 316929654
| -rw-r--r-- | pkg/sentry/fsimpl/host/host.go | 4 | ||||
| -rw-r--r-- | pkg/sentry/fsimpl/host/util.go | 10 |
2 files changed, 3 insertions, 11 deletions
diff --git a/pkg/sentry/fsimpl/host/host.go b/pkg/sentry/fsimpl/host/host.go index 7906242c9..2b084860e 100644 --- a/pkg/sentry/fsimpl/host/host.go +++ b/pkg/sentry/fsimpl/host/host.go @@ -91,7 +91,9 @@ func NewFD(ctx context.Context, mnt *vfs.Mount, hostFD int, opts *NewFDOptions) isTTY: opts.IsTTY, wouldBlock: wouldBlock(uint32(fileType)), seekable: seekable, - canMap: canMap(uint32(fileType)), + // NOTE(b/38213152): Technically, some obscure char devices can be memory + // mapped, but we only allow regular files. + canMap: fileType == linux.S_IFREG, } i.pf.inode = i diff --git a/pkg/sentry/fsimpl/host/util.go b/pkg/sentry/fsimpl/host/util.go index 2bc757b1a..412bdb2eb 100644 --- a/pkg/sentry/fsimpl/host/util.go +++ b/pkg/sentry/fsimpl/host/util.go @@ -49,16 +49,6 @@ func wouldBlock(fileType uint32) bool { return fileType == syscall.S_IFIFO || fileType == syscall.S_IFCHR || fileType == syscall.S_IFSOCK } -// canMap returns true if a file with fileType is allowed to be memory mapped. -// This is ported over from VFS1, but it's probably not the best way for us -// to check if a file can be memory mapped. -func canMap(fileType uint32) bool { - // TODO(gvisor.dev/issue/1672): Also allow "special files" to be mapped (see fs/host:canMap()). - // - // TODO(b/38213152): Some obscure character devices can be mapped. - return fileType == syscall.S_IFREG -} - // isBlockError checks if an error is EAGAIN or EWOULDBLOCK. // If so, they can be transformed into syserror.ErrWouldBlock. func isBlockError(err error) bool { |