Commit 5abcd76f authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge branch 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 

Pull x86 bootup changes from Ingo Molnar:
 "Deal with bootloaders which fail to initialize unknown fields in
  boot_params to zero, by sanitizing boot params passed in.

  This unbreaks versions of kexec-utils.  Other bootloaders do not
  appear to show sensitivity to this change, but it's a possibility for
  breakage nevertheless."

* 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86, boot: Sanitize boot_params if not zeroed on creation
parents a57ed936 5dcd14ec

arch/x86/boot/compressed/misc.c

+2 −0
Original line number Diff line number Diff line
@@ -325,6 +325,8 @@ asmlinkage void decompress_kernel(void *rmode, memptr heap, 
{

	real_mode = rmode;



	sanitize_boot_params(real_mode);



	if (real_mode->screen_info.orig_video_mode == 7) {

		vidmem = (char *) 0xb0000;

		vidport = 0x3b4;

arch/x86/boot/compressed/misc.h

+1 −0
Original line number Diff line number Diff line
@@ -18,6 +18,7 @@ 
#include <asm/page.h>

#include <asm/boot.h>

#include <asm/bootparam.h>

#include <asm/bootparam_utils.h>



#define BOOT_BOOT_H

#include "../ctype.h"

arch/x86/include/asm/bootparam_utils.h

0 → 100644
+38 −0
Original line number Diff line number Diff line 
#ifndef _ASM_X86_BOOTPARAM_UTILS_H

#define _ASM_X86_BOOTPARAM_UTILS_H



#include <asm/bootparam.h>



/*

 * This file is included from multiple environments.  Do not

 * add completing #includes to make it standalone.

 */



/*

 * Deal with bootloaders which fail to initialize unknown fields in

 * boot_params to zero.  The list fields in this list are taken from

 * analysis of kexec-tools; if other broken bootloaders initialize a

 * different set of fields we will need to figure out how to disambiguate.

 *

 */

static void sanitize_boot_params(struct boot_params *boot_params)

{

	if (boot_params->sentinel) {

		/*fields in boot_params are not valid, clear them */

		memset(&boot_params->olpc_ofw_header, 0,

		       (char *)&boot_params->alt_mem_k -

			(char *)&boot_params->olpc_ofw_header);

		memset(&boot_params->kbd_status, 0,

		       (char *)&boot_params->hdr -

		       (char *)&boot_params->kbd_status);

		memset(&boot_params->_pad7[0], 0,

		       (char *)&boot_params->edd_mbr_sig_buffer[0] -

			(char *)&boot_params->_pad7[0]);

		memset(&boot_params->_pad8[0], 0,

		       (char *)&boot_params->eddbuf[0] -

			(char *)&boot_params->_pad8[0]);

		memset(&boot_params->_pad9[0], 0, sizeof(boot_params->_pad9));

	}

}



#endif /* _ASM_X86_BOOTPARAM_UTILS_H */

arch/x86/kernel/head32.c

+3 −0
Original line number Diff line number Diff line
@@ -18,6 +18,7 @@ 
#include <asm/io_apic.h>

#include <asm/bios_ebda.h>

#include <asm/tlbflush.h>

#include <asm/bootparam_utils.h>



static void __init i386_default_early_setup(void)

{
@@ -30,6 +31,8 @@ static void __init i386_default_early_setup(void) 


void __init i386_start_kernel(void)

{

	sanitize_boot_params(&boot_params);



	memblock_reserve(__pa_symbol(&_text),

			 __pa_symbol(&__bss_stop) - __pa_symbol(&_text));

arch/x86/kernel/head64.c

+2 −0
Original line number Diff line number Diff line
@@ -25,6 +25,7 @@ 
#include <asm/kdebug.h>

#include <asm/e820.h>

#include <asm/bios_ebda.h>

#include <asm/bootparam_utils.h>



static void __init zap_identity_mappings(void)

{
@@ -46,6 +47,7 @@ static void __init copy_bootdata(char *real_mode_data) 
	char * command_line;



	memcpy(&boot_params, real_mode_data, sizeof boot_params);

	sanitize_boot_params(&boot_params);

	if (boot_params.hdr.cmd_line_ptr) {

		command_line = __va(boot_params.hdr.cmd_line_ptr);

		memcpy(boot_command_line, command_line, COMMAND_LINE_SIZE);

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