Module Name: src
Committed By: maxv
Date: Fri Aug 18 10:28:53 UTC 2017
Modified Files:
src/sys/arch/amd64/conf: kern.ldscript
src/sys/arch/i386/conf: kern.ldscript kern.ldscript.4MB
Log Message:
Fill the .text padding with 0xcc (int3), in such a way that any jump into
this area will automatically fault. The alignment within the section is
necessary, in order to fill strictly all of the padding (took me a while
to figure this out); but it does not change the kernel size.
Greatly inspired from FreeBSD, but for some reason they decided not to
apply the alignment.
To generate a diff of this commit:
cvs rdiff -u -r1.23 -r1.24 src/sys/arch/amd64/conf/kern.ldscript
cvs rdiff -u -r1.19 -r1.20 src/sys/arch/i386/conf/kern.ldscript
cvs rdiff -u -r1.17 -r1.18 src/sys/arch/i386/conf/kern.ldscript.4MB
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/arch/amd64/conf/kern.ldscript
diff -u src/sys/arch/amd64/conf/kern.ldscript:1.23 src/sys/arch/amd64/conf/kern.ldscript:1.24
--- src/sys/arch/amd64/conf/kern.ldscript:1.23 Wed Jun 14 07:45:45 2017
+++ src/sys/arch/amd64/conf/kern.ldscript Fri Aug 18 10:28:53 2017
@@ -1,4 +1,4 @@
-/* $NetBSD: kern.ldscript,v 1.23 2017/06/14 07:45:45 maxv Exp $ */
+/* $NetBSD: kern.ldscript,v 1.24 2017/08/18 10:28:53 maxv Exp $ */
#include "assym.h"
@@ -13,12 +13,13 @@ __LARGE_PAGE_SIZE = 0x200000 ;
ENTRY(_start)
SECTIONS
{
- .text :
+ .text : AT (ADDR(.text) & 0x0fffffff)
{
*(.text)
*(.text.*)
*(.stub)
- }
+ . = ALIGN(__LARGE_PAGE_SIZE);
+ } =0xCC
_etext = . ;
PROVIDE (etext = .) ;
@@ -79,11 +80,3 @@ SECTIONS
}
}
-SECTIONS
-{
- .text :
- AT (ADDR(.text) & 0x0fffffff)
- {
- *(.text)
- } = 0
-}
Index: src/sys/arch/i386/conf/kern.ldscript
diff -u src/sys/arch/i386/conf/kern.ldscript:1.19 src/sys/arch/i386/conf/kern.ldscript:1.20
--- src/sys/arch/i386/conf/kern.ldscript:1.19 Sat May 14 08:19:42 2016
+++ src/sys/arch/i386/conf/kern.ldscript Fri Aug 18 10:28:53 2017
@@ -1,4 +1,4 @@
-/* $NetBSD: kern.ldscript,v 1.19 2016/05/14 08:19:42 maxv Exp $ */
+/* $NetBSD: kern.ldscript,v 1.20 2017/08/18 10:28:53 maxv Exp $ */
#include "assym.h"
@@ -7,12 +7,13 @@ __PAGE_SIZE = 0x1000 ;
ENTRY(_start)
SECTIONS
{
- .text :
+ .text : AT (ADDR(.text) & 0x0fffffff)
{
*(.text)
*(.text.*)
*(.stub)
- }
+ . = ALIGN(__PAGE_SIZE);
+ } =0xCC
_etext = . ;
PROVIDE (etext = .) ;
@@ -69,11 +70,3 @@ SECTIONS
}
}
-SECTIONS
-{
- .text :
- AT (ADDR(.text) & 0x0fffffff)
- {
- *(.text)
- } = 0
-}
Index: src/sys/arch/i386/conf/kern.ldscript.4MB
diff -u src/sys/arch/i386/conf/kern.ldscript.4MB:1.17 src/sys/arch/i386/conf/kern.ldscript.4MB:1.18
--- src/sys/arch/i386/conf/kern.ldscript.4MB:1.17 Mon May 16 07:52:31 2016
+++ src/sys/arch/i386/conf/kern.ldscript.4MB Fri Aug 18 10:28:53 2017
@@ -1,4 +1,4 @@
-/* $NetBSD: kern.ldscript.4MB,v 1.17 2016/05/16 07:52:31 maxv Exp $ */
+/* $NetBSD: kern.ldscript.4MB,v 1.18 2017/08/18 10:28:53 maxv Exp $ */
#include "assym.h"
@@ -12,12 +12,13 @@ __LARGE_PAGE_SIZE = 0x400000 ;
ENTRY(_start)
SECTIONS
{
- .text :
+ .text : AT (ADDR(.text) & 0x0fffffff)
{
*(.text)
*(.text.*)
*(.stub)
- }
+ . = ALIGN(__LARGE_PAGE_SIZE);
+ } =0xCC
_etext = . ;
PROVIDE (etext = .) ;
@@ -78,11 +79,3 @@ SECTIONS
}
}
-SECTIONS
-{
- .text :
- AT (ADDR(.text) & 0x0fffffff)
- {
- *(.text)
- } = 0
-}
