Reverted logic change, removed GNU_STACK missing text

Author: devx00

pwnlib/elf/elf.py

@@ -1924,7 +1924,7 @@ def nx(self):
                 return False
             return None
         elif self.arch == 'amd64':
-            return missing or non_exec
+            return True if non_exec else None
         elif self.arch == 'powerpc':
             return not missing
         elif self.arch == 'powerpc64':
@@ -2074,7 +2074,7 @@ def checksec(self, banner=True, color=True):
             "NX:".ljust(12) + {
                 True:  green("NX enabled"),
                 False: red("NX disabled"),
-                None: yellow("NX unknown - GNU_STACK missing"),
+                None: yellow("NX unknown"),
             }[self.nx],
             "PIE:".ljust(12) + {
                 True: green("PIE enabled"),