From 696feaf10c9339a57d177a913e847ddb488ece69 Mon Sep 17 00:00:00 2001 From: Nicolas Lacasse Date: Thu, 23 Apr 2020 17:32:59 -0700 Subject: Port devpts to VFS2. PiperOrigin-RevId: 308164359 --- pkg/sentry/fsimpl/devtmpfs/devtmpfs.go | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-) (limited to 'pkg/sentry/fsimpl/devtmpfs/devtmpfs.go') diff --git a/pkg/sentry/fsimpl/devtmpfs/devtmpfs.go b/pkg/sentry/fsimpl/devtmpfs/devtmpfs.go index 64f1b142c..142ee53b0 100644 --- a/pkg/sentry/fsimpl/devtmpfs/devtmpfs.go +++ b/pkg/sentry/fsimpl/devtmpfs/devtmpfs.go @@ -163,16 +163,25 @@ func (a *Accessor) CreateDeviceFile(ctx context.Context, pathname string, kind v func (a *Accessor) UserspaceInit(ctx context.Context) error { actx := a.wrapContext(ctx) - // systemd: src/shared/dev-setup.c:dev_setup() + // Initialize symlinks. for _, symlink := range []struct { source string target string }{ - // /proc/kcore is not implemented. + // systemd: src/shared/dev-setup.c:dev_setup() {source: "fd", target: "/proc/self/fd"}, {source: "stdin", target: "/proc/self/fd/0"}, {source: "stdout", target: "/proc/self/fd/1"}, {source: "stderr", target: "/proc/self/fd/2"}, + // /proc/kcore is not implemented. + + // Linux implements /dev/ptmx as a device node, but advises + // container implementations to create /dev/ptmx as a symlink + // to pts/ptmx (Documentation/filesystems/devpts.txt). Systemd + // follows this advice (src/nspawn/nspawn.c:setup_pts()), while + // LXC tries to create a bind mount and falls back to a symlink + // (src/lxc/conf.c:lxc_setup_devpts()). + {source: "ptmx", target: "pts/ptmx"}, } { if err := a.vfsObj.SymlinkAt(actx, a.creds, a.pathOperationAt(symlink.source), symlink.target); err != nil { return fmt.Errorf("failed to create symlink %q => %q: %v", symlink.source, symlink.target, err) -- cgit v1.2.3