Merge pull request #10598

12098ff p2p: restore safe sync mode when target height drops (selsta)

ACKs: SChernykh, thomasbuilds, j-berman

src/cryptonote_protocol/cryptonote_protocol_handler.inl

@@ -2841,6 +2841,8 @@ skip:
     {
       MINFO("Target height decreasing from " << previous_target << " to " << target);
       m_core.set_target_blockchain_height(target);
+      if (target < m_core.get_current_blockchain_height() + 5)
+        m_core.safesyncmode(true);
       if (target == 0 && context.m_state > cryptonote_connection_context::state_before_handshake && !m_stopping)
       {
         MCWARNING("global", "monerod is now disconnected from the network");