DTLS: Sanity check on return value from DtlsTransport.Receive

bcgit · Feb 5, 2024 · 601768c · 601768c
1 parent 0b52881
commit 601768c
Showing 1 changed file with 9 additions and 7 deletions.
diff --git a/crypto/src/tls/DtlsRecordLayer.cs b/crypto/src/tls/DtlsRecordLayer.cs
@@ -654,25 +654,27 @@ private int ReceiveDatagram(byte[] buf, int off, int len, int waitMillis)
         {
             try
             {
-                return m_transport.Receive(buf, off, len, waitMillis);
+                // NOTE: the buffer is sized to support m_transport.GetReceiveLimit().
+                int received = m_transport.Receive(buf, off, len, waitMillis);
+
+                // Check the transport returned a sensible value, otherwise discard the datagram.
+                if (received <= len)
+                    return received;
             }
             catch (TlsTimeoutException)
             {
-                return -1;
             }
-            catch (SocketException e)
+            catch (SocketException e) when (TlsUtilities.IsTimeout(e))
             {
-                if (TlsUtilities.IsTimeout(e))
-                    return -1;
-
-                throw;
             }
             // TODO[tls-port] Can we support interrupted IO on .NET?
             //catch (InterruptedIOException e)
             //{
             //    e.bytesTransferred = 0;
             //    throw;
             //}
+
+            return -1;
         }
 
         // TODO Include 'currentTimeMillis' as an argument, use with Timeout, resetHeartbeat