From e50be6f7bab47c271e718dabae027c9c3590e4b9 Mon Sep 17 00:00:00 2001
From: Tamir Duberstein <tamird@google.com>
Date: Fri, 28 Aug 2020 05:31:46 -0700
Subject: Add test demonstrating accept bug

Updates #3780.

PiperOrigin-RevId: 328922573
---
 test/syscalls/linux/socket_inet_loopback.cc | 76 +++++++++++++++++++++++++++++
 1 file changed, 76 insertions(+)

diff --git a/test/syscalls/linux/socket_inet_loopback.cc b/test/syscalls/linux/socket_inet_loopback.cc
index 67893033c..425084228 100644
--- a/test/syscalls/linux/socket_inet_loopback.cc
+++ b/test/syscalls/linux/socket_inet_loopback.cc
@@ -1111,6 +1111,82 @@ TEST_P(SocketInetLoopbackTest, AcceptedInheritsTCPUserTimeout) {
   EXPECT_EQ(get, kUserTimeout);
 }
 
+TEST_P(SocketInetLoopbackTest, TCPAcceptAfterReset) {
+  auto const& param = GetParam();
+  TestAddress const& listener = param.listener;
+  TestAddress const& connector = param.connector;
+
+  // Create the listening socket.
+  const FileDescriptor listen_fd = ASSERT_NO_ERRNO_AND_VALUE(
+      Socket(listener.family(), SOCK_STREAM, IPPROTO_TCP));
+  sockaddr_storage listen_addr = listener.addr;
+  ASSERT_THAT(bind(listen_fd.get(), reinterpret_cast<sockaddr*>(&listen_addr),
+                   listener.addr_len),
+              SyscallSucceeds());
+  ASSERT_THAT(listen(listen_fd.get(), SOMAXCONN), SyscallSucceeds());
+
+  // Get the port bound by the listening socket.
+  {
+    socklen_t addrlen = listener.addr_len;
+    ASSERT_THAT(
+        getsockname(listen_fd.get(), reinterpret_cast<sockaddr*>(&listen_addr),
+                    &addrlen),
+        SyscallSucceeds());
+  }
+
+  const uint16_t port =
+      ASSERT_NO_ERRNO_AND_VALUE(AddrPort(listener.family(), listen_addr));
+
+  // Connect to the listening socket.
+  FileDescriptor conn_fd = ASSERT_NO_ERRNO_AND_VALUE(
+      Socket(connector.family(), SOCK_STREAM, IPPROTO_TCP));
+
+  sockaddr_storage conn_addr = connector.addr;
+  ASSERT_NO_ERRNO(SetAddrPort(connector.family(), &conn_addr, port));
+  ASSERT_THAT(RetryEINTR(connect)(conn_fd.get(),
+                                  reinterpret_cast<sockaddr*>(&conn_addr),
+                                  connector.addr_len),
+              SyscallSucceeds());
+
+  // Trigger a RST by turning linger off and closing the socket.
+  struct linger opt = {
+      .l_onoff = 1,
+      .l_linger = 0,
+  };
+  ASSERT_THAT(
+      setsockopt(conn_fd.get(), SOL_SOCKET, SO_LINGER, &opt, sizeof(opt)),
+      SyscallSucceeds());
+  ASSERT_THAT(close(conn_fd.release()), SyscallSucceeds());
+
+  // TODO(gvisor.dev/issue/3780): Remove this.
+  if (IsRunningOnGvisor()) {
+    // Wait for the RST to be observed.
+    absl::SleepFor(absl::Milliseconds(100));
+  }
+
+  sockaddr_storage accept_addr;
+  socklen_t addrlen = sizeof(accept_addr);
+
+  // TODO(gvisor.dev/issue/3780): Remove this.
+  if (IsRunningOnGvisor()) {
+    ASSERT_THAT(accept(listen_fd.get(),
+                       reinterpret_cast<sockaddr*>(&accept_addr), &addrlen),
+                SyscallFailsWithErrno(ENOTCONN));
+    return;
+  }
+
+  conn_fd = ASSERT_NO_ERRNO_AND_VALUE(Accept(
+      listen_fd.get(), reinterpret_cast<sockaddr*>(&accept_addr), &addrlen));
+  ASSERT_EQ(addrlen, listener.addr_len);
+
+  int err;
+  socklen_t optlen = sizeof(err);
+  ASSERT_THAT(getsockopt(conn_fd.get(), SOL_SOCKET, SO_ERROR, &err, &optlen),
+              SyscallSucceeds());
+  ASSERT_EQ(err, ECONNRESET);
+  ASSERT_EQ(optlen, sizeof(err));
+}
+
 // TODO(gvisor.dev/issue/1688): Partially completed passive endpoints are not
 // saved. Enable S/R once issue is fixed.
 TEST_P(SocketInetLoopbackTest, TCPDeferAccept_NoRandomSave) {
-- 
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