[Crash-utility] crash: invalid structure member offset with current kernels

[Sebastian Ott]

Hi,

Crash fails to start with current (4.4+) kernels. The following patch
fixes this.

Regards,
Sebastian
----->8

>From ddd809812705ba36796c6750d12a12838b4106ec Mon Sep 17 00:00:00 2001
From: Sebastian Ott <sebott at linux.vnet.ibm.com>
Date: Tue, 19 Jan 2016 14:14:13 +0100
Subject: [PATCH] Fix invalid structure member offset.

Struct module was changed by kernel commit
7523e4dc50 "module: use a structure to encapsulate layout."

Fix the offsets to handle the following crash error:

crash: invalid structure member offset: module_init_text_size
       FILE: symbols.c  LINE: 1668  FUNCTION: store_module_symbols_v2()

[../crash/crash] error trace: 10062e92 => 10109812 => 1014f16e => 101813ac

  101813ac: OFFSET_verify+124
  1014f16e: store_module_symbols_v2+2182
  10109812: module_init+4386
  10062e92: main_loop+410

Signed-off-by: Sebastian Ott <sebott at linux.vnet.ibm.com>
---
 kernel.c | 49 +++++++++++++++++++++++++++++++++++++++----------
 1 file changed, 39 insertions(+), 10 deletions(-)

diff --git a/kernel.c b/kernel.c
index 2d4188a..5ce2fb9 100644
--- a/kernel.c
+++ b/kernel.c
@@ -3291,16 +3291,45 @@ module_init(void)
         	MEMBER_OFFSET_INIT(module_gpl_syms, "module", "gpl_syms");
         	MEMBER_OFFSET_INIT(module_num_gpl_syms, "module", 
 			"num_gpl_syms");
-        	MEMBER_OFFSET_INIT(module_module_core, "module", 
-			"module_core");
-        	MEMBER_OFFSET_INIT(module_core_size, "module", 
-			"core_size");
-        	MEMBER_OFFSET_INIT(module_core_text_size, "module", 
-			"core_text_size");
-		MEMBER_OFFSET_INIT(module_module_init, "module", "module_init");
-		MEMBER_OFFSET_INIT(module_init_size, "module", "init_size");
-		MEMBER_OFFSET_INIT(module_init_text_size, "module", 
-			"init_text_size");
+
+		if (MEMBER_EXISTS("module", "module_core")) {
+			MEMBER_OFFSET_INIT(module_core_size, "module",
+					   "core_size");
+			MEMBER_OFFSET_INIT(module_init_size, "module",
+					   "init_size");
+
+			MEMBER_OFFSET_INIT(module_core_text_size, "module",
+					   "core_text_size");
+			MEMBER_OFFSET_INIT(module_init_text_size, "module",
+					   "init_text_size");
+
+			MEMBER_OFFSET_INIT(module_module_core, "module",
+					   "module_core");
+			MEMBER_OFFSET_INIT(module_module_init, "module",
+					   "module_init");
+		} else {
+			ASSIGN_OFFSET(module_core_size) =
+				MEMBER_OFFSET("module", "core_layout") +
+				MEMBER_OFFSET("module_layout", "size");
+			ASSIGN_OFFSET(module_init_size) =
+				MEMBER_OFFSET("module", "init_layout") +
+				MEMBER_OFFSET("module_layout", "size");
+
+			ASSIGN_OFFSET(module_core_text_size) =
+				MEMBER_OFFSET("module", "core_layout") +
+				MEMBER_OFFSET("module_layout", "text_size");
+			ASSIGN_OFFSET(module_init_text_size) =
+				MEMBER_OFFSET("module", "init_layout") +
+				MEMBER_OFFSET("module_layout", "text_size");
+
+			ASSIGN_OFFSET(module_module_core) =
+				MEMBER_OFFSET("module", "core_layout") +
+				MEMBER_OFFSET("module_layout", "base");
+			ASSIGN_OFFSET(module_module_init) =
+				MEMBER_OFFSET("module", "init_layout") +
+				MEMBER_OFFSET("module_layout", "base");
+		}
+
 		MEMBER_OFFSET_INIT(module_percpu, "module", "percpu");
 
 		/*
-- 
2.3.0