From 1b0f6fd558ee372b4d44c97de05e1c50bf913c50 Mon Sep 17 00:00:00 2001
From: mehrdadn <mehrdadn@users.noreply.github.com>
Date: Mon, 13 Apr 2020 09:30:01 -0700
Subject: [PATCH] Check AF_UNIX path length (#7951)

---
 python/ray/node.py                | 7 +++++++
 python/ray/tests/test_tempfile.py | 6 ++++++
 src/ray/util/util.cc              | 3 +++
 3 files changed, 16 insertions(+)

diff --git a/python/ray/node.py b/python/ray/node.py
index 8a50ac7c3..884c3f220 100644
--- a/python/ray/node.py
+++ b/python/ray/node.py
@@ -394,6 +394,7 @@ class Node:
             socket_path (string): the socket file to prepare.
         """
         result = socket_path
+        is_mac = sys.platform.startswith("darwin")
         if sys.platform == "win32":
             if socket_path is None:
                 result = "tcp://{}:{}".format(self._localhost,
@@ -407,6 +408,12 @@ class Node:
                     raise RuntimeError(
                         "Socket file {} exists!".format(socket_path))
                 try_to_create_directory(os.path.dirname(socket_path))
+
+            # Check socket path length to make sure it's short enough
+            maxlen = (104 if is_mac else 108) - 1  # sockaddr_un->sun_path
+            if len(result.split("://", 1)[-1].encode("utf-8")) > maxlen:
+                raise OSError("AF_UNIX path length cannot exceed "
+                              "{} bytes: {!r}".format(maxlen, result))
         return result
 
     def start_reaper_process(self):
diff --git a/python/ray/tests/test_tempfile.py b/python/ray/tests/test_tempfile.py
index 0e174fd23..13554632f 100644
--- a/python/ray/tests/test_tempfile.py
+++ b/python/ray/tests/test_tempfile.py
@@ -72,6 +72,12 @@ def test_tempdir_commandline():
         ignore_errors=True)
 
 
+def test_tempdir_long_path():
+    temp_dir = os.path.join(ray.utils.get_user_temp_dir(), "z" * 108)
+    with pytest.raises(OSError):
+        ray.init(temp_dir=temp_dir)  # path should be too long
+
+
 def test_raylet_socket_name(shutdown_only):
     ray.init(
         raylet_socket_name=os.path.join(ray.utils.get_user_temp_dir(),
diff --git a/src/ray/util/util.cc b/src/ray/util/util.cc
index f94a24dc2..df49304b5 100644
--- a/src/ray/util/util.cc
+++ b/src/ray/util/util.cc
@@ -100,6 +100,9 @@ ParseUrlEndpoint(const std::string &endpoint, int default_port) {
   }
   if (scheme == "unix://") {
 #ifdef BOOST_ASIO_HAS_LOCAL_SOCKETS
+    size_t maxlen = sizeof(sockaddr_un().sun_path) / sizeof(*sockaddr_un().sun_path) - 1;
+    RAY_CHECK(address.size() <= maxlen)
+        << "AF_UNIX path length cannot exceed " << maxlen << " bytes: " << address;
     result = boost::asio::local::stream_protocol::endpoint(address);
 #else
     RAY_LOG(FATAL) << "UNIX-domain socket endpoints are not supported: " << endpoint;