diff options
| author | Dean Deng <deandeng@google.com> | 2020-10-14 09:52:05 -0700 |
|---|---|---|
| committer | gVisor bot <gvisor-bot@google.com> | 2020-10-14 09:54:05 -0700 |
| commit | fc1e653973c97a857582b8f3651399673343589a (patch) | |
| tree | 0c66c65ddce71cadcdf4fe8940bad5d12fc139e7 /pkg/sentry/syscalls/linux | |
| parent | a7b7b7b9804e9968c1fed5f7b3849233f585a88b (diff) | |
Fix SCM Rights reference leaks.
Control messages should be released on Read (which ignores the control message)
or zero-byte Send. Otherwise, open fds sent through the control messages will
be leaked.
PiperOrigin-RevId: 337110774
Diffstat (limited to 'pkg/sentry/syscalls/linux')
| -rw-r--r-- | pkg/sentry/syscalls/linux/sys_socket.go | 4 | ||||
| -rw-r--r-- | pkg/sentry/syscalls/linux/vfs2/socket.go | 4 |
2 files changed, 6 insertions, 2 deletions
diff --git a/pkg/sentry/syscalls/linux/sys_socket.go b/pkg/sentry/syscalls/linux/sys_socket.go index 9feaca0da..9cd052c3d 100644 --- a/pkg/sentry/syscalls/linux/sys_socket.go +++ b/pkg/sentry/syscalls/linux/sys_socket.go @@ -1052,7 +1052,9 @@ func sendSingleMsg(t *kernel.Task, s socket.Socket, file *fs.File, msgPtr userme // Call the syscall implementation. n, e := s.SendMsg(t, src, to, int(flags), haveDeadline, deadline, controlMessages) err = handleIOError(t, n != 0, e.ToError(), syserror.ERESTARTSYS, "sendmsg", file) - if err != nil { + // Control messages should be released on error as well as for zero-length + // messages, which are discarded by the receiver. + if n == 0 || err != nil { controlMessages.Release(t) } return uintptr(n), err diff --git a/pkg/sentry/syscalls/linux/vfs2/socket.go b/pkg/sentry/syscalls/linux/vfs2/socket.go index bfae6b7e9..7b33b3f59 100644 --- a/pkg/sentry/syscalls/linux/vfs2/socket.go +++ b/pkg/sentry/syscalls/linux/vfs2/socket.go @@ -1055,7 +1055,9 @@ func sendSingleMsg(t *kernel.Task, s socket.SocketVFS2, file *vfs.FileDescriptio // Call the syscall implementation. n, e := s.SendMsg(t, src, to, int(flags), haveDeadline, deadline, controlMessages) err = slinux.HandleIOErrorVFS2(t, n != 0, e.ToError(), syserror.ERESTARTSYS, "sendmsg", file) - if err != nil { + // Control messages should be released on error as well as for zero-length + // messages, which are discarded by the receiver. + if n == 0 || err != nil { controlMessages.Release(t) } return uintptr(n), err |