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
Signed-off-by: Kuan-Ying Lee <kuan-ying.lee@xxxxxxxxxxxxx>
---
scripts/gdb/linux/kasan.py | 44 ++++++++++++++++++++++++++++++++++++++
scripts/gdb/vmlinux-gdb.py | 1 +
2 files changed, 45 insertions(+)
create mode 100644 scripts/gdb/linux/kasan.py
diff --git a/scripts/gdb/linux/kasan.py b/scripts/gdb/linux/kasan.py
new file mode 100644
index 000000000000..56730b3fde0b
--- /dev/null
+++ b/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()
diff --git a/scripts/gdb/vmlinux-gdb.py b/scripts/gdb/vmlinux-gdb.py
index fc53cdf286f1..d4eeed4506fd 100644
--- a/scripts/gdb/vmlinux-gdb.py
+++ b/scripts/gdb/vmlinux-gdb.py
@@ -49,3 +49,4 @@ else:
import linux.page_owner
import linux.slab
import linux.vmalloc
+ import linux.kasan
--
2.34.1
