The patch titled
Subject: scripts/gdb: add 'lx-kasan_mem_to_shadow' command
has been added to the -mm mm-nonmm-unstable branch. Its filename is
scripts-gdb-add-lx-kasan_mem_to_shadow-command.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/scripts-gdb-add-lx-kasan_mem_to_shadow-command.patch
This patch will later appear in the mm-nonmm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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------------------------------------------------------
From: Kuan-Ying Lee <kuan-ying.lee@xxxxxxxxxxxxx>
Subject: scripts/gdb: add 'lx-kasan_mem_to_shadow' command
Date: Tue, 23 Jul 2024 14:49:01 +0800
This command allows users to quickly translate memory address to the kasan
shadow memory address.
Example output:
(gdb) lx-kasan_mem_to_shadow 0xffff000019acc008
shadow addr: 0xffff600003359801
Link: https://lkml.kernel.org/r/20240723064902.124154-6-kuan-ying.lee@xxxxxxxxxxxxx
Signed-off-by: Kuan-Ying Lee <kuan-ying.lee@xxxxxxxxxxxxx>
Cc: Jan Kiszka <jan.kiszka@xxxxxxxxxxx>
Cc: Kieran Bingham <kbingham@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
scripts/gdb/linux/kasan.py | 44 +++++++++++++++++++++++++++++++++++
scripts/gdb/vmlinux-gdb.py | 1
2 files changed, 45 insertions(+)
--- /dev/null
+++ a/scripts/gdb/linux/kasan.py
@@ -0,0 +1,44 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# Copyright 2024 Canonical Ltd.
+#
+# Authors:
+# Kuan-Ying Lee <kuan-ying.lee@xxxxxxxxxxxxx>
+#
+
+import gdb
+from linux import constants, mm
+
+def help():
+ t = """Usage: lx-kasan_mem_to_shadow [Hex memory addr]
+ Example:
+ lx-kasan_mem_to_shadow 0xffff000008eca008\n"""
+ gdb.write("Unrecognized command\n")
+ raise gdb.GdbError(t)
+
+class KasanMemToShadow(gdb.Command):
+ """Translate memory address to kasan shadow address"""
+
+ p_ops = None
+
+ def __init__(self):
+ if constants.LX_CONFIG_KASAN_GENERIC or constants.LX_CONFIG_KASAN_SW_TAGS:
+ super(KasanMemToShadow, self).__init__("lx-kasan_mem_to_shadow", gdb.COMMAND_SUPPORT)
+
+ def invoke(self, args, from_tty):
+ if not constants.LX_CONFIG_KASAN_GENERIC or constants.LX_CONFIG_KASAN_SW_TAGS:
+ raise gdb.GdbError('CONFIG_KASAN_GENERIC or CONFIG_KASAN_SW_TAGS is not set')
+
+ argv = gdb.string_to_argv(args)
+ if len(argv) == 1:
+ if self.p_ops is None:
+ self.p_ops = mm.page_ops().ops
+ addr = int(argv[0], 16)
+ shadow_addr = self.kasan_mem_to_shadow(addr)
+ gdb.write('shadow addr: 0x%x\n' % shadow_addr)
+ else:
+ help()
+ def kasan_mem_to_shadow(self, addr):
+ return (addr >> self.p_ops.KASAN_SHADOW_SCALE_SHIFT) + self.p_ops.KASAN_SHADOW_OFFSET
+
+KasanMemToShadow()
--- a/scripts/gdb/vmlinux-gdb.py~scripts-gdb-add-lx-kasan_mem_to_shadow-command
+++ a/scripts/gdb/vmlinux-gdb.py
@@ -49,3 +49,4 @@ else:
import linux.page_owner
import linux.slab
import linux.vmalloc
+ import linux.kasan
_
Patches currently in -mm which might be from kuan-ying.lee@xxxxxxxxxxxxx are
scripts-gdb-fix-timerlist-parsing-issue.patch
scripts-gdb-add-iteration-function-for-rbtree.patch
scripts-gdb-fix-lx-mounts-command-error.patch
scripts-gdb-add-lx-stack_depot_lookup-command.patch
scripts-gdb-add-lx-kasan_mem_to_shadow-command.patch
