From 390171590b3934e12f78e27ee879e00174941b42 Mon Sep 17 00:00:00 2001
From: Boris Zbarsky <bzbarsky@apple.com>
Date: Wed, 26 Jul 2023 10:40:32 -0400
Subject: [PATCH] Make sure we clean up properly if StartWatchingSocket fails.
 (#28245)

If StartWatchingSocket failed (e.g. due to us being out of socket watch pool
space), we would leave the UDPEndPointImplSockets in a bad state where its
destructor would try to treat the un-initialized mWatch value as a pointer.

The fix is to make sure we clean up properly on StartWatchingSocket failure.
---
 src/inet/UDPEndPointImplSockets.cpp | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/src/inet/UDPEndPointImplSockets.cpp b/src/inet/UDPEndPointImplSockets.cpp
index 5c9748d0cf32fb..b681a56fabe92f 100644
--- a/src/inet/UDPEndPointImplSockets.cpp
+++ b/src/inet/UDPEndPointImplSockets.cpp
@@ -469,7 +469,14 @@ CHIP_ERROR UDPEndPointImplSockets::GetSocket(IPAddressType addressType)
         {
             return CHIP_ERROR_POSIX(errno);
         }
-        ReturnErrorOnFailure(static_cast<System::LayerSockets *>(&GetSystemLayer())->StartWatchingSocket(mSocket, &mWatch));
+        CHIP_ERROR err = static_cast<System::LayerSockets *>(&GetSystemLayer())->StartWatchingSocket(mSocket, &mWatch);
+        if (err != CHIP_NO_ERROR)
+        {
+            // Our mWatch is not valid; make sure we never use it.
+            close(mSocket);
+            mSocket = kInvalidSocketFd;
+            return err;
+        }
 
         mAddrType = addressType;