Randomize the link order of .o files in the kernel on octeon.

Unlike on some other architectures, it is not possible to unmap
the early boot code. Instead, the code is smashed during boot.

Input from deraadt@

diff --git a/sys/arch/octeon/conf/Makefile.octeon b/sys/arch/octeon/conf/Makefile.octeon
index e291ac3..bb47dec 100644 (file)
--- a/sys/arch/octeon/conf/Makefile.octeon
+++ b/sys/arch/octeon/conf/Makefile.octeon
@@ -1,4 +1,4 @@
-#      $OpenBSD: Makefile.octeon,v 1.32 2017/06/05 12:43:59 deraadt Exp $
+#      $OpenBSD: Makefile.octeon,v 1.33 2017/06/05 15:23:11 visa Exp $
 
 # For instructions on building kernels consult the config(8) and options(4)
 # manual pages.
@@ -36,9 +36,13 @@ CWARNFLAGS=  -Werror -Wall -Wimplicit-function-declaration \
 
 CMACHFLAGS=    -mno-abicalls ${ABI} -msoft-float -G 0
 CMACHFLAGS+=   -ffreestanding ${NOPIE_FLAGS}
+SORTR=         sort -R
 .if ${IDENT:M-DNO_PROPOLICE}
 CMACHFLAGS+=   -fno-stack-protector
 .endif
+.if ${IDENT:M-DSMALL_KERNEL}
+SORTR=         cat
+.endif
 
 DEBUG?=                -g
 COPTS?=                -O2
@@ -73,13 +77,14 @@ NORMAL_S=   ${CC} ${AFLAGS} ${CPPFLAGS} -c $<
 #      ${SYSTEM_LD_HEAD}
 #      ${SYSTEM_LD} swapxxx.o
 #      ${SYSTEM_LD_TAIL}
-SYSTEM_HEAD=   locore.o param.o ioconf.o
-SYSTEM_OBJ=    ${SYSTEM_HEAD} ${OBJS}
+SYSTEM_HEAD=   locore0.o gap.o
+SYSTEM_OBJ=    ${SYSTEM_HEAD} ${OBJS} param.o ioconf.o
 SYSTEM_DEP=    Makefile ${SYSTEM_OBJ} ld.script
 SYSTEM_LD_HEAD=        @rm -f $@
 SYSTEM_LD=     @echo ${LD} ${LINKFLAGS} -o $@ '$${SYSTEM_HEAD} vers.o $${OBJS}'; \
                umask 007; \
-               ${LD} ${LINKFLAGS} -o $@ ${SYSTEM_HEAD} vers.o ${OBJS}
+               echo ${OBJS} param.o ioconf.o vers.o | tr " " "\n" | ${SORTR} > lorder; \
+               ${LD} ${LINKFLAGS} -o $@ ${SYSTEM_HEAD} `cat lorder`
 SYSTEM_LD_TAIL=        @${SIZE} $@
 
 .if ${DEBUG} == "-g"
@@ -126,8 +131,15 @@ vers.o: ${SYSTEM_DEP} ${SYSTEM_SWAP_DEP}
        sh $S/conf/newvers.sh
        ${CC} ${CFLAGS} ${CPPFLAGS} ${PROF} -c vers.c
 
+gap.S: ${SYSTEM_SWAP_DEP} Makefile $S/conf/makegap.sh
+       umask 007; sh $S/conf/makegap.sh 0xef > gap.S
+
+gap.o: gap.S
+       umask 007; ${CC} ${AFLAGS} ${CPPFLAGS} ${PROF} -c gap.S
+
 clean:
-       rm -f *bsd *bsd.gdb *.[dio] [a-z]*.s assym.* ${DB_STRUCTINFO} param.c
+       rm -f *bsd *bsd.gdb *.[dio] [a-z]*.s assym.* ${DB_STRUCTINFO} \
+           gap.S lorder param.c
 
 cleandir: clean
        rm -f Makefile *.h ioconf.c options machine ${_mach} vers.c
@@ -143,8 +155,8 @@ db_structinfo.h: $S/ddb/db_structinfo.c $S/ddb/parse_structinfo.pl
        objdump -g db_structinfo.o | perl $S/ddb/parse_structinfo.pl > $@
        rm -f db_structinfo.o
 
-locore.o: ${_machdir}/${_mach}/locore.S assym.h
-context.o cp0access.o exception.o: assym.h
+locore0.o: ${_machdir}/${_mach}/locore0.S assym.h
+context.o cp0access.o exception.o locore.o: assym.h
 lcore_access.o lcore_ddb.o lcore_float.o tlbhandler.o: assym.h
 mips64r2.o: assym.h
 

diff --git a/sys/arch/octeon/conf/files.octeon b/sys/arch/octeon/conf/files.octeon
index 813cab1..800ff0f 100644 (file)
--- a/sys/arch/octeon/conf/files.octeon
+++ b/sys/arch/octeon/conf/files.octeon
@@ -1,4 +1,4 @@
-#      $OpenBSD: files.octeon,v 1.35 2017/05/02 13:26:49 visa Exp $
+#      $OpenBSD: files.octeon,v 1.36 2017/06/05 15:23:11 visa Exp $
 
 # Standard stanzas config(8) can't run without
 maxpartitions 16
@@ -20,6 +20,7 @@ file  arch/octeon/octeon/conf.c
 file   arch/octeon/octeon/disksubr.c           disk
 file   arch/octeon/octeon/machdep.c
 file   arch/octeon/octeon/cn3xxx_dts.S
+file   arch/octeon/octeon/locore.S
 
 include "dev/ata/files.ata"
 include "dev/atapiscsi/files.atapiscsi"

diff --git a/sys/arch/octeon/octeon/locore.S b/sys/arch/octeon/octeon/locore.S
index 3ef892a..579a2eb 100644 (file)
--- a/sys/arch/octeon/octeon/locore.S
+++ b/sys/arch/octeon/octeon/locore.S
@@ -1,4 +1,4 @@
-/*     $OpenBSD: locore.S,v 1.12 2017/05/09 15:11:33 visa Exp $ */
+/*     $OpenBSD: locore.S,v 1.13 2017/06/05 15:23:11 visa Exp $ */
 
 /*
  * Copyright (c) 2001-2004 Opsycon AB  (www.opsycon.se / www.opsycon.com)
@@ -44,10 +44,8 @@
 
        .set    noreorder               # Noreorder is default style!
        .set    mips64r2
-       .globl  start
-       .globl  kernel_text
-kernel_text = start
-start:
+       .globl  locore_start
+locore_start:
 /* initialize ebase */
        dla     t0, 0xffffffff80000000
        mtc0    t0, COP_0_EBASE
@@ -123,6 +121,17 @@ start:
        blt     t0, t1, 1b
        sd      v0, -8(t0)                      # store to randomdata
 
+       /*
+        * Smash the very early boot code by overwriting it.
+        */
+       li      v0, 0x00000034                  # TEQ zero, zero
+       LA      t0, start
+       LA      t1, endboot
+1:
+       daddu   t0, t0, 4
+       blt     t0, t1, 1b
+       sw      v0, -4(t0)
+
        /*
         * Initialize stack and call machine startup.
         */

diff --git a/sys/arch/octeon/octeon/locore0.S b/sys/arch/octeon/octeon/locore0.S
new file mode 100644 (file)
index 0000000..b57089f
--- /dev/null
+++ b/sys/arch/octeon/octeon/locore0.S
@@ -0,0 +1,41 @@
+/*     $OpenBSD: locore0.S,v 1.1 2017/06/05 15:23:11 visa Exp $        */
+
+/*
+ * Copyright (c) 2001-2004 Opsycon AB  (www.opsycon.se / www.opsycon.com)
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS
+ * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
+ * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ */
+
+#include <machine/param.h>
+#include <machine/asm.h>
+
+#include "assym.h"
+
+       .set    noreorder               # Noreorder is default style!
+       .set    mips64r2
+       .globl  start
+       .globl  kernel_text
+kernel_text = start
+start:
+       j       locore_start
+       nop