From 4ae9dbbbca1623787ab88a378e17bbfdec99727b Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Simon=20W=C3=B6rner?= <git@simon-woerner.de>
Date: Fri, 21 May 2021 17:07:42 +0200
Subject: [PATCH] fix address underflow on disassemble (#652)

---
 gef.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/gef.py b/gef.py
index eee7cb268..6e98e6777 100644
--- a/gef.py
+++ b/gef.py
@@ -1303,7 +1303,7 @@ def gdb_get_nth_previous_instruction_address(addr, n):
     """Return the address (Integer) of the `n`-th instruction before `addr`."""
     # fixed-length ABI
     if current_arch.instruction_length:
-        return addr - n * current_arch.instruction_length
+        return max(0, addr - n * current_arch.instruction_length)
 
     # variable-length ABI
     cur_insn_addr = gef_current_instruction(addr).address