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
......@@ -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;
......
......@@ -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"
......
#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 */
......@@ -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));
......
......@@ -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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