diff --git a/src/sim/syscall_emul.hh b/src/sim/syscall_emul.hh
index 8a73cb2..e2f2fc2 100644
--- a/src/sim/syscall_emul.hh
+++ b/src/sim/syscall_emul.hh
@@ -1338,7 +1338,7 @@
     int tgt_fd = p->getSyscallArg(tc, index);
     Addr bufPtr = p->getSyscallArg(tc, index);
 
-    auto ffdp = std::dynamic_pointer_cast<FileFDEntry>((*p->fds)[tgt_fd]);
+    auto ffdp = std::dynamic_pointer_cast<HBFDEntry>((*p->fds)[tgt_fd]);
     if (!ffdp)
         return -EBADF;
     int sim_fd = ffdp->getSimFD();