Bugfixes, make errno better

pwndbg/commands/misc.py

@@ -13,8 +13,8 @@ _errno.errorcode[0] = 'OK'
 @_pwndbg.commands.ParsedCommand
 def errno(err=None):
     if err is None:
-        err = _pwndbg.regs.retval
-        err = _pwndbg.regs[err]
+        # Dont ask.
+        err = int(gdb.parse_and_eval('*((int *(*) (void)) __errno_location) ()'))
 
     err = abs(int(err))
 

pwndbg/disasm/__init__.py

@@ -104,6 +104,9 @@ def get(address, instructions=1):
 def near(address, instructions=1):
     current = one(address)
 
+    if not current:
+        return []
+
     # Try to go backward by seeing which instructions we've returned
     # before, which were followed by this one.
     needle = address