scripts/gdb/linux/kasan.py

   1 # SPDX-License-Identifier: GPL-2.0
   2 #
   3 # Copyright 2024 Canonical Ltd.
   4 #
   5 # Authors:
   6 #  Kuan-Ying Lee <[email protected]>
   7 #
   8
   9 import gdb
  10 from linux import constants, mm
  11
  12 def help():
  13     t = """Usage: lx-kasan_mem_to_shadow [Hex memory addr]
  14     Example:
  15         lx-kasan_mem_to_shadow 0xffff000008eca008\n"""
  16     gdb.write("Unrecognized command\n")
  17     raise gdb.GdbError(t)
  18
  19 class KasanMemToShadow(gdb.Command):
  20     """Translate memory address to kasan shadow address"""
  21
  22     p_ops = None
  23
  24     def __init__(self):
  25         if constants.LX_CONFIG_KASAN_GENERIC or constants.LX_CONFIG_KASAN_SW_TAGS:
  26             super(KasanMemToShadow, self).__init__("lx-kasan_mem_to_shadow", gdb.COMMAND_SUPPORT)
  27
  28     def invoke(self, args, from_tty):
  29         if not constants.LX_CONFIG_KASAN_GENERIC or constants.LX_CONFIG_KASAN_SW_TAGS:
  30             raise gdb.GdbError('CONFIG_KASAN_GENERIC or CONFIG_KASAN_SW_TAGS is not set')
  31
  32         argv = gdb.string_to_argv(args)
  33         if len(argv) == 1:
  34             if self.p_ops is None:
  35                 self.p_ops = mm.page_ops().ops
  36             addr = int(argv[0], 16)
  37             shadow_addr = self.kasan_mem_to_shadow(addr)
  38             gdb.write('shadow addr: 0x%x\n' % shadow_addr)
  39         else:
  40             help()
  41     def kasan_mem_to_shadow(self, addr):
  42         return (addr >> self.p_ops.KASAN_SHADOW_SCALE_SHIFT) + self.p_ops.KASAN_SHADOW_OFFSET
  43
  44 KasanMemToShadow()