diff --git a/Kernel/Net/IPv4Socket.h b/Kernel/Net/IPv4Socket.h
index e9ef4eef59..48d5e3301e 100644
--- a/Kernel/Net/IPv4Socket.h
+++ b/Kernel/Net/IPv4Socket.h
@@ -90,6 +90,8 @@ protected:
     static ErrorOr<NonnullOwnPtr<DoubleBuffer>> try_create_receive_buffer();
     void drop_receive_buffer();
 
+    size_t available_space_in_receive_buffer() const { return m_receive_buffer ? m_receive_buffer->space_for_writing() : 0; }
+
 private:
     virtual bool is_ipv4() const override { return true; }
 
diff --git a/Kernel/Net/TCPSocket.cpp b/Kernel/Net/TCPSocket.cpp
index fbf69fae05..1e5caa2599 100644
--- a/Kernel/Net/TCPSocket.cpp
+++ b/Kernel/Net/TCPSocket.cpp
@@ -260,7 +260,7 @@ ErrorOr<void> TCPSocket::send_tcp_packet(u16 flags, UserOrKernelBuffer const* pa
     VERIFY(local_port());
     tcp_packet.set_source_port(local_port());
     tcp_packet.set_destination_port(peer_port());
-    tcp_packet.set_window_size(NumericLimits<u16>::max());
+    tcp_packet.set_window_size(min(available_space_in_receive_buffer(), NumericLimits<u16>::max()));
     tcp_packet.set_sequence_number(m_sequence_number);
     tcp_packet.set_data_offset(tcp_header_size / sizeof(u32));
     tcp_packet.set_flags(flags);