diff --git a/core/future.hh b/core/future.hh
index 067b384c57..c716840234 100644
--- a/core/future.hh
+++ b/core/future.hh
@@ -341,6 +341,9 @@ private:
     friend class future;
 };
 
+template<>
+class promise<void> : public promise<> {};
+
 template <typename... T> struct is_future : std::false_type {};
 template <typename... T> struct is_future<future<T...>> : std::true_type {};
 
diff --git a/core/xen/xenstore.hh b/core/xen/xenstore.hh
index fe60682dea..a496a80c59 100644
--- a/core/xen/xenstore.hh
+++ b/core/xen/xenstore.hh
@@ -22,6 +22,8 @@
 #ifndef XENSTORE_HH_
 #define XENSTORE_HH_
 
+#include <list>
+
 extern "C" {
     #include <xenstore.h>
 }
diff --git a/net/tcp.hh b/net/tcp.hh
index 648846a0cc..188acb6d5b 100644
--- a/net/tcp.hh
+++ b/net/tcp.hh
@@ -915,8 +915,9 @@ void tcp<InetTraits>::tcb::init_from_options(tcp_hdr* th, uint8_t* opt_start, ui
 
 template <typename InetTraits>
 void tcp<InetTraits>::tcb::input_handle_listen_state(tcp_hdr* th, packet p) {
-    auto opt_start = p.get_header<uint8_t>(sizeof(tcp_hdr));
-    auto opt_end = opt_start + th->data_offset * 4;
+    auto opt_len = th->data_offset * 4 - sizeof(tcp_hdr);
+    auto opt_start = reinterpret_cast<uint8_t*>(p.get_header(0, th->data_offset * 4)) + sizeof(tcp_hdr);
+    auto opt_end = opt_start + opt_len;
     p.trim_front(th->data_offset * 4);
     tcp_seq seg_seq = th->seq;
 
@@ -943,8 +944,9 @@ void tcp<InetTraits>::tcb::input_handle_listen_state(tcp_hdr* th, packet p) {
 
 template <typename InetTraits>
 void tcp<InetTraits>::tcb::input_handle_syn_sent_state(tcp_hdr* th, packet p) {
-    auto opt_start = p.get_header<uint8_t>(sizeof(tcp_hdr));
-    auto opt_end = opt_start + th->data_offset * 4;
+    auto opt_len = th->data_offset * 4 - sizeof(tcp_hdr);
+    auto opt_start = reinterpret_cast<uint8_t*>(p.get_header(0, th->data_offset * 4)) + sizeof(tcp_hdr);
+    auto opt_end = opt_start + opt_len;
     p.trim_front(th->data_offset * 4);
     tcp_seq seg_seq = th->seq;
     auto seg_ack = th->ack;
diff --git a/net/virtio.cc b/net/virtio.cc
index 0c09543948..72185fddd9 100644
--- a/net/virtio.cc
+++ b/net/virtio.cc
@@ -554,6 +554,7 @@ protected:
     private:
         future<> prepare_buffers();
         void complete_buffer(single_buffer&& b, size_t len);
+        void debug_mode_adjust_fragments();
     };
 protected:
     device* _dev;
@@ -666,6 +667,22 @@ qp::rxq::prepare_buffers() {
     });
 }
 
+void
+qp::rxq::debug_mode_adjust_fragments() {
+#ifdef DEBUG
+    // For debug mode, reallocate last fragment to detect buffer overruns
+    auto last = _fragments.back();
+    auto sz = last.size;
+    std::unique_ptr<char[], free_deleter> buf(reinterpret_cast<char*>(malloc(sz)));
+    if (!buf) {
+        throw std::bad_alloc();
+    }
+    std::copy_n(last.base, sz, buf.get());
+    _fragments.back() = { buf.get(), sz };
+    _buffers.back() = std::move(buf);
+#endif
+}
+
 void
 qp::rxq::complete_buffer(single_buffer&& bc, size_t len) {
     auto&& sb = bc[0];
@@ -690,6 +707,7 @@ qp::rxq::complete_buffer(single_buffer&& bc, size_t len) {
 
     // Last buffer
     if (_remaining_buffers == 0) {
+        debug_mode_adjust_fragments();
         deleter del;
         if (_buffers.size() == 1) {
             del = make_free_deleter(_buffers[0].release());