diff options
| author | Dean Deng <deandeng@google.com> | 2020-04-28 20:11:43 -0700 |
|---|---|---|
| committer | gVisor bot <gvisor-bot@google.com> | 2020-04-28 20:13:01 -0700 |
| commit | ce19497c1c0829af6ba56f0cc68e3a4cb33cf1c8 (patch) | |
| tree | c8fe75216dfda0345e048e72d0641fc0fadcccbb /pkg/sentry/socket/unix | |
| parent | 24abccbc1c3b7b0dd06b6da97e5b4c90c8c13907 (diff) | |
Fix Unix socket permissions.
Enforce write permission checks in BoundEndpointAt, which corresponds to the
permission checks in Linux (net/unix/af_unix.c:unix_find_other).
Also, create bound socket files with the correct permissions in VFS2.
Fixes #2324.
PiperOrigin-RevId: 308949084
Diffstat (limited to 'pkg/sentry/socket/unix')
| -rw-r--r-- | pkg/sentry/socket/unix/unix.go | 5 | ||||
| -rw-r--r-- | pkg/sentry/socket/unix/unix_vfs2.go | 12 |
2 files changed, 11 insertions, 6 deletions
diff --git a/pkg/sentry/socket/unix/unix.go b/pkg/sentry/socket/unix/unix.go index ddd0eda4b..5b29e9d7f 100644 --- a/pkg/sentry/socket/unix/unix.go +++ b/pkg/sentry/socket/unix/unix.go @@ -323,7 +323,10 @@ func (s *SocketOperations) Bind(t *kernel.Task, sockaddr []byte) *syserr.Error { // Create the socket. // - // TODO(gvisor.dev/issue/2324): Correctly set file permissions. + // Note that the file permissions here are not set correctly (see + // gvisor.dev/issue/2324). There is no convenient way to get permissions + // on the socket referred to by s, so we will leave this discrepancy + // unresolved until VFS2 replaces this code. childDir, err := d.Bind(t, t.FSContext().RootDirectory(), name, bep, fs.FilePermissions{User: fs.PermMask{Read: true}}) if err != nil { return syserr.ErrPortInUse diff --git a/pkg/sentry/socket/unix/unix_vfs2.go b/pkg/sentry/socket/unix/unix_vfs2.go index 433cde9cb..23db93f33 100644 --- a/pkg/sentry/socket/unix/unix_vfs2.go +++ b/pkg/sentry/socket/unix/unix_vfs2.go @@ -197,11 +197,13 @@ func (s *SocketVFS2) Bind(t *kernel.Task, sockaddr []byte) *syserr.Error { Start: start, Path: path, } - err := t.Kernel().VFS().MknodAt(t, t.Credentials(), &pop, &vfs.MknodOptions{ - // TODO(gvisor.dev/issue/2324): The file permissions should be taken - // from s and t.FSContext().Umask() (see net/unix/af_unix.c:unix_bind), - // but VFS1 just always uses 0400. Resolve this inconsistency. - Mode: linux.S_IFSOCK | 0400, + stat, err := s.vfsfd.Stat(t, vfs.StatOptions{Mask: linux.STATX_MODE}) + if err != nil { + return syserr.FromError(err) + } + err = t.Kernel().VFS().MknodAt(t, t.Credentials(), &pop, &vfs.MknodOptions{ + // File permissions correspond to net/unix/af_unix.c:unix_bind. + Mode: linux.FileMode(linux.S_IFSOCK | uint(stat.Mode)&^t.FSContext().Umask()), Endpoint: bep, }) if err == syserror.EEXIST { |