Module Name: src
Committed By: maxv
Date: Thu May 12 07:21:18 UTC 2016
Modified Files:
src/sys/arch/amd64/amd64: locore.S
src/sys/arch/amd64/conf: kern.ldscript
Log Message:
Map the rodata segment independently on amd64, and remove the W permission
on it.
To generate a diff of this commit:
cvs rdiff -u -r1.87 -r1.88 src/sys/arch/amd64/amd64/locore.S
cvs rdiff -u -r1.19 -r1.20 src/sys/arch/amd64/conf/kern.ldscript
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/amd64/locore.S
diff -u src/sys/arch/amd64/amd64/locore.S:1.87 src/sys/arch/amd64/amd64/locore.S:1.88
--- src/sys/arch/amd64/amd64/locore.S:1.87 Thu May 12 06:45:16 2016
+++ src/sys/arch/amd64/amd64/locore.S Thu May 12 07:21:18 2016
@@ -1,4 +1,4 @@
-/* $NetBSD: locore.S,v 1.87 2016/05/12 06:45:16 maxv Exp $ */
+/* $NetBSD: locore.S,v 1.88 2016/05/12 07:21:18 maxv Exp $ */
/*
* Copyright-o-rama!
@@ -564,6 +564,8 @@ no_NOX:
*
* (PROC0 STK + L4 + L3 + L2 + L1) is later referred to as BOOTSTRAP TABLES.
*
+ * Important note: the kernel segments are properly 4k-aligned
+ * (see kern.ldscript), so there's no need to enforce alignment.
*/
/* Find end of kernel image; brings us on (1). */
@@ -616,16 +618,16 @@ no_NOX:
shrl $(PGSHIFT-3),%ecx /* ((n >> PGSHIFT) << 3) for # PDEs */
addl %ecx,%ebx
- /*
- * Compute &__rodata_start - KERNBASE. This can't be > 4G, or we can't
- * deal with it anyway, since we can't load it in 32 bit mode. So use
- * the bottom 32 bits.
- */
- movl $RELOC(__rodata_start),%edx
- andl $~PGOFSET,%edx
+ /* Map the kernel text RX. */
+ movl $RELOC(__rodata_start),%ecx
+ subl %eax,%ecx
+ shrl $PGSHIFT,%ecx
+ orl $(PG_V|PG_KR),%eax
+ fillkpt
- /* Map the kernel text read-only. */
- movl %edx,%ecx
+ /* Map the kernel rodata ROX. */
+ movl $RELOC(__rodata_start),%eax
+ movl $RELOC(__data_start),%ecx
subl %eax,%ecx
shrl $PGSHIFT,%ecx
orl $(PG_V|PG_KR),%eax
@@ -639,11 +641,12 @@ no_NOX:
* +--------+----------+-------------------+------------------+
* We just map everything from < to > with RWX rights.
*/
- leal (PG_V|PG_KW)(%edx),%eax
- movl $TABLESIZE,%ecx
- addl %esi,%ecx /* end of tables */
- subl %edx,%ecx /* subtract end of text */
+ movl $RELOC(__data_start),%eax
+ movl %esi,%ecx /* start of BOOTSTRAP TABLES */
+ addl $TABLESIZE,%ecx /* end of BOOTSTRAP TABLES */
+ subl %eax,%ecx /* subtract start of DATA */
shrl $PGSHIFT,%ecx
+ orl $(PG_V|PG_KW),%eax
fillkpt
/* We are on (4). Map ISA I/O mem (later atdevbase) RWX. */
Index: src/sys/arch/amd64/conf/kern.ldscript
diff -u src/sys/arch/amd64/conf/kern.ldscript:1.19 src/sys/arch/amd64/conf/kern.ldscript:1.20
--- src/sys/arch/amd64/conf/kern.ldscript:1.19 Thu May 12 06:45:16 2016
+++ src/sys/arch/amd64/conf/kern.ldscript Thu May 12 07:21:18 2016
@@ -1,4 +1,4 @@
-/* $NetBSD: kern.ldscript,v 1.19 2016/05/12 06:45:16 maxv Exp $ */
+/* $NetBSD: kern.ldscript,v 1.20 2016/05/12 07:21:18 maxv Exp $ */
#include "assym.h"
@@ -36,6 +36,8 @@ SECTIONS
*(.rodata.*)
}
+ . = ALIGN(__PAGE_SIZE);
+
__data_start = . ;
.data :
{
