+ scripts-gdb-add-lx-kasan_mem_to_shadow-command.patch added to mm-nonmm-unstable branch

+ scripts-gdb-add-lx-kasan_mem_to_shadow-command.patch added to mm-nonmm-unstable branch

[Andrew Morton]

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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branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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------------------------------------------------------
From: Kuan-Ying Lee <kuan-ying.lee@canonical.com>
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@canonical.com
Signed-off-by: Kuan-Ying Lee <kuan-ying.lee@canonical.com>
Cc: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Kieran Bingham <kbingham@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 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@canonical.com>
+#
+
+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@canonical.com 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