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501009 |
/*
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Packit Service |
501009 |
* kaslr_helper - helper for kaslr offset calculation
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501009 |
*
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501009 |
* Copyright (c) 2011 FUJITSU LIMITED
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501009 |
* Copyright (c) 2018 Red Hat Inc.
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501009 |
*
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501009 |
* This program is free software; you can redistribute it and/or modify
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501009 |
* it under the terms of the GNU General Public License as published by
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501009 |
* the Free Software Foundation; either version 2 of the License, or
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501009 |
* (at your option) any later version.
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501009 |
*
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501009 |
* This program is distributed in the hope that it will be useful,
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501009 |
* but WITHOUT ANY WARRANTY; without even the implied warranty of
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501009 |
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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501009 |
* GNU General Public License for more details.
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501009 |
*
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501009 |
* Authors: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com>
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501009 |
* INDOH Takao <indou.takao@jp.fujitsu.com>
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501009 |
* Sergio Lopez <slp@redhat.com>
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501009 |
*/
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501009 |
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501009 |
#include "defs.h"
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501009 |
#include <elf.h>
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501009 |
#include <inttypes.h>
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501009 |
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501009 |
#ifdef X86_64
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501009 |
/*
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501009 |
* Get address of vector0 interrupt handler (Devide Error) from Interrupt
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501009 |
* Descriptor Table.
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501009 |
*/
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501009 |
static ulong
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501009 |
get_vec0_addr(ulong idtr)
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501009 |
{
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501009 |
struct gate_struct64 {
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501009 |
uint16_t offset_low;
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501009 |
uint16_t segment;
|
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501009 |
uint32_t ist : 3, zero0 : 5, type : 5, dpl : 2, p : 1;
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501009 |
uint16_t offset_middle;
|
|
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501009 |
uint32_t offset_high;
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501009 |
uint32_t zero1;
|
|
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501009 |
} __attribute__((packed)) gate;
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501009 |
|
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501009 |
readmem(idtr, PHYSADDR, &gate, sizeof(gate), "idt_table", FAULT_ON_ERROR);
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|
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return ((ulong)gate.offset_high << 32)
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+ ((ulong)gate.offset_middle << 16)
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|
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+ gate.offset_low;
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}
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501009 |
|
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501009 |
/*
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501009 |
* Parse a string of [size[KMG] ]offset[KMG]
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501009 |
* Import from Linux kernel(lib/cmdline.c)
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*/
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static ulong
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501009 |
memparse(char *ptr, char **retptr)
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|
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501009 |
{
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501009 |
char *endptr;
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501009 |
|
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501009 |
unsigned long long ret = strtoull(ptr, &endptr, 0);
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501009 |
|
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501009 |
switch (*endptr) {
|
|
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501009 |
case 'E':
|
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501009 |
case 'e':
|
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501009 |
ret <<= 10;
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|
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501009 |
case 'P':
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501009 |
case 'p':
|
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501009 |
ret <<= 10;
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|
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501009 |
case 'T':
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501009 |
case 't':
|
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501009 |
ret <<= 10;
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|
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501009 |
case 'G':
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501009 |
case 'g':
|
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501009 |
ret <<= 10;
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|
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501009 |
case 'M':
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501009 |
case 'm':
|
|
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501009 |
ret <<= 10;
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|
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501009 |
case 'K':
|
|
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501009 |
case 'k':
|
|
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501009 |
ret <<= 10;
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|
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501009 |
endptr++;
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|
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501009 |
default:
|
|
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501009 |
break;
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|
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501009 |
}
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|
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501009 |
|
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501009 |
if (retptr)
|
|
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501009 |
*retptr = endptr;
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|
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501009 |
|
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501009 |
return ret;
|
|
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501009 |
}
|
|
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501009 |
|
|
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501009 |
/*
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501009 |
* Find "elfcorehdr=" in the boot parameter of kernel and return the address
|
|
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501009 |
* of elfcorehdr.
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|
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501009 |
*/
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501009 |
static ulong
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501009 |
get_elfcorehdr(ulong kaslr_offset)
|
|
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501009 |
{
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|
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501009 |
char cmdline[BUFSIZE], *ptr;
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|
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501009 |
ulong cmdline_vaddr;
|
|
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501009 |
ulong cmdline_paddr;
|
|
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501009 |
ulong buf_vaddr, buf_paddr;
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|
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501009 |
char *end;
|
|
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501009 |
ulong elfcorehdr_addr = 0, elfcorehdr_size = 0;
|
|
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501009 |
int verbose = CRASHDEBUG(1)? 1: 0;
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|
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501009 |
|
|
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501009 |
cmdline_vaddr = st->saved_command_line_vmlinux + kaslr_offset;
|
|
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501009 |
if (!kvtop(NULL, cmdline_vaddr, &cmdline_paddr, verbose))
|
|
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501009 |
return 0;
|
|
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501009 |
|
|
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501009 |
if (CRASHDEBUG(1)) {
|
|
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501009 |
fprintf(fp, "cmdline vaddr=%lx\n", cmdline_vaddr);
|
|
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501009 |
fprintf(fp, "cmdline paddr=%lx\n", cmdline_paddr);
|
|
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501009 |
}
|
|
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501009 |
|
|
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501009 |
if (!readmem(cmdline_paddr, PHYSADDR, &buf_vaddr, sizeof(ulong),
|
|
Packit Service |
501009 |
"saved_command_line", RETURN_ON_ERROR))
|
|
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501009 |
return 0;
|
|
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501009 |
|
|
Packit Service |
501009 |
if (!kvtop(NULL, buf_vaddr, &buf_paddr, verbose))
|
|
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501009 |
return 0;
|
|
Packit Service |
501009 |
|
|
Packit Service |
501009 |
if (CRASHDEBUG(1)) {
|
|
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501009 |
fprintf(fp, "cmdline buffer vaddr=%lx\n", buf_vaddr);
|
|
Packit Service |
501009 |
fprintf(fp, "cmdline buffer paddr=%lx\n", buf_paddr);
|
|
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501009 |
}
|
|
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501009 |
|
|
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501009 |
memset(cmdline, 0, BUFSIZE);
|
|
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501009 |
if (!readmem(buf_paddr, PHYSADDR, cmdline, BUFSIZE,
|
|
Packit Service |
501009 |
"saved_command_line", RETURN_ON_ERROR))
|
|
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501009 |
return 0;
|
|
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501009 |
|
|
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501009 |
ptr = strstr(cmdline, "elfcorehdr=");
|
|
Packit Service |
501009 |
if (!ptr)
|
|
Packit Service |
501009 |
return 0;
|
|
Packit Service |
501009 |
|
|
Packit Service |
501009 |
if (CRASHDEBUG(1))
|
|
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501009 |
fprintf(fp, "2nd kernel detected\n");
|
|
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501009 |
|
|
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501009 |
ptr += strlen("elfcorehdr=");
|
|
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501009 |
elfcorehdr_addr = memparse(ptr, &end;;
|
|
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501009 |
if (*end == '@') {
|
|
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501009 |
elfcorehdr_size = elfcorehdr_addr;
|
|
Packit Service |
501009 |
elfcorehdr_addr = memparse(end + 1, &end;;
|
|
Packit Service |
501009 |
}
|
|
Packit Service |
501009 |
|
|
Packit Service |
501009 |
if (CRASHDEBUG(1)) {
|
|
Packit Service |
501009 |
fprintf(fp, "elfcorehdr_addr=%lx\n", elfcorehdr_addr);
|
|
Packit Service |
501009 |
fprintf(fp, "elfcorehdr_size=%lx\n", elfcorehdr_size);
|
|
Packit Service |
501009 |
}
|
|
Packit Service |
501009 |
|
|
Packit Service |
501009 |
return elfcorehdr_addr;
|
|
Packit Service |
501009 |
}
|
|
Packit Service |
501009 |
|
|
Packit Service |
501009 |
/*
|
|
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501009 |
* Get vmcoreinfo from elfcorehdr.
|
|
Packit Service |
501009 |
* Some codes are imported from Linux kernel(fs/proc/vmcore.c)
|
|
Packit Service |
501009 |
*/
|
|
Packit Service |
501009 |
static int
|
|
Packit Service |
501009 |
get_vmcoreinfo(ulong elfcorehdr, ulong *addr, int *len)
|
|
Packit Service |
501009 |
{
|
|
Packit Service |
501009 |
unsigned char e_ident[EI_NIDENT];
|
|
Packit Service |
501009 |
Elf64_Ehdr ehdr;
|
|
Packit Service |
501009 |
Elf64_Phdr phdr;
|
|
Packit Service |
501009 |
Elf64_Nhdr nhdr;
|
|
Packit Service |
501009 |
ulong ptr;
|
|
Packit Service |
501009 |
ulong nhdr_offset = 0;
|
|
Packit Service |
501009 |
int i;
|
|
Packit Service |
501009 |
|
|
Packit Service |
501009 |
if (!readmem(elfcorehdr, PHYSADDR, e_ident, EI_NIDENT,
|
|
Packit Service |
501009 |
"EI_NIDENT", RETURN_ON_ERROR))
|
|
Packit Service |
501009 |
return FALSE;
|
|
Packit Service |
501009 |
|
|
Packit Service |
501009 |
if (e_ident[EI_CLASS] != ELFCLASS64) {
|
|
Packit Service |
501009 |
error(INFO, "Only ELFCLASS64 is supportd\n");
|
|
Packit Service |
501009 |
return FALSE;
|
|
Packit Service |
501009 |
}
|
|
Packit Service |
501009 |
|
|
Packit Service |
501009 |
if (!readmem(elfcorehdr, PHYSADDR, &ehdr, sizeof(ehdr),
|
|
Packit Service |
501009 |
"Elf64_Ehdr", RETURN_ON_ERROR))
|
|
Packit Service |
501009 |
return FALSE;
|
|
Packit Service |
501009 |
|
|
Packit Service |
501009 |
/* Sanity Check */
|
|
Packit Service |
501009 |
if (memcmp(ehdr.e_ident, ELFMAG, SELFMAG) != 0 ||
|
|
Packit Service |
501009 |
(ehdr.e_type != ET_CORE) ||
|
|
Packit Service |
501009 |
ehdr.e_ident[EI_CLASS] != ELFCLASS64 ||
|
|
Packit Service |
501009 |
ehdr.e_ident[EI_VERSION] != EV_CURRENT ||
|
|
Packit Service |
501009 |
ehdr.e_version != EV_CURRENT ||
|
|
Packit Service |
501009 |
ehdr.e_ehsize != sizeof(Elf64_Ehdr) ||
|
|
Packit Service |
501009 |
ehdr.e_phentsize != sizeof(Elf64_Phdr) ||
|
|
Packit Service |
501009 |
ehdr.e_phnum == 0) {
|
|
Packit Service |
501009 |
error(INFO, "Invalid elf header\n");
|
|
Packit Service |
501009 |
return FALSE;
|
|
Packit Service |
501009 |
}
|
|
Packit Service |
501009 |
|
|
Packit Service |
501009 |
ptr = elfcorehdr + ehdr.e_phoff;
|
|
Packit Service |
501009 |
for (i = 0; i < ehdr.e_phnum; i++) {
|
|
Packit Service |
501009 |
ulong offset;
|
|
Packit Service |
501009 |
char name[16];
|
|
Packit Service |
501009 |
|
|
Packit Service |
501009 |
if (!readmem(ptr, PHYSADDR, &phdr, sizeof(phdr),
|
|
Packit Service |
501009 |
"Elf64_Phdr", RETURN_ON_ERROR))
|
|
Packit Service |
501009 |
return FALSE;
|
|
Packit Service |
501009 |
|
|
Packit Service |
501009 |
ptr += sizeof(phdr);
|
|
Packit Service |
501009 |
if (phdr.p_type != PT_NOTE)
|
|
Packit Service |
501009 |
continue;
|
|
Packit Service |
501009 |
|
|
Packit Service |
501009 |
offset = phdr.p_offset;
|
|
Packit Service |
501009 |
if (!readmem(offset, PHYSADDR, &nhdr, sizeof(nhdr),
|
|
Packit Service |
501009 |
"Elf64_Nhdr", RETURN_ON_ERROR))
|
|
Packit Service |
501009 |
return FALSE;
|
|
Packit Service |
501009 |
|
|
Packit Service |
501009 |
offset += DIV_ROUND_UP(sizeof(Elf64_Nhdr), sizeof(Elf64_Word))*
|
|
Packit Service |
501009 |
sizeof(Elf64_Word);
|
|
Packit Service |
501009 |
memset(name, 0, sizeof(name));
|
|
Packit Service |
501009 |
if (!readmem(offset, PHYSADDR, name, sizeof(name),
|
|
Packit Service |
501009 |
"Elf64_Nhdr name", RETURN_ON_ERROR))
|
|
Packit Service |
501009 |
return FALSE;
|
|
Packit Service |
501009 |
|
|
Packit Service |
501009 |
if(!strcmp(name, "VMCOREINFO")) {
|
|
Packit Service |
501009 |
nhdr_offset = offset;
|
|
Packit Service |
501009 |
break;
|
|
Packit Service |
501009 |
}
|
|
Packit Service |
501009 |
}
|
|
Packit Service |
501009 |
|
|
Packit Service |
501009 |
if (!nhdr_offset)
|
|
Packit Service |
501009 |
return FALSE;
|
|
Packit Service |
501009 |
|
|
Packit Service |
501009 |
*addr = nhdr_offset +
|
|
Packit Service |
501009 |
DIV_ROUND_UP(nhdr.n_namesz, sizeof(Elf64_Word))*
|
|
Packit Service |
501009 |
sizeof(Elf64_Word);
|
|
Packit Service |
501009 |
*len = nhdr.n_descsz;
|
|
Packit Service |
501009 |
|
|
Packit Service |
501009 |
if (CRASHDEBUG(1)) {
|
|
Packit Service |
501009 |
fprintf(fp, "vmcoreinfo addr=%lx\n", *addr);
|
|
Packit Service |
501009 |
fprintf(fp, "vmcoreinfo len=%d\n", *len);
|
|
Packit Service |
501009 |
}
|
|
Packit Service |
501009 |
|
|
Packit Service |
501009 |
return TRUE;
|
|
Packit Service |
501009 |
}
|
|
Packit Service |
501009 |
|
|
Packit Service |
501009 |
static int
|
|
Packit Service |
501009 |
qemu_get_cr3_idtr(ulong *cr3, ulong *idtr)
|
|
Packit Service |
501009 |
{
|
|
Packit Service |
501009 |
QEMUCPUState *cpustat;
|
|
Packit Service |
501009 |
|
|
Packit Service |
501009 |
if (DISKDUMP_DUMPFILE()) {
|
|
Packit Service |
501009 |
cpustat = diskdump_get_qemucpustate(0);
|
|
Packit Service |
501009 |
} else if (KDUMP_DUMPFILE()) {
|
|
Packit Service |
501009 |
cpustat = kdump_get_qemucpustate(0);
|
|
Packit Service |
501009 |
} else {
|
|
Packit Service |
501009 |
return FALSE;
|
|
Packit Service |
501009 |
}
|
|
Packit Service |
501009 |
|
|
Packit Service |
501009 |
if (!cpustat) {
|
|
Packit Service |
501009 |
return FALSE;
|
|
Packit Service |
501009 |
}
|
|
Packit Service |
501009 |
|
|
Packit Service |
501009 |
*cr3 = cpustat->cr[3];
|
|
Packit Service |
501009 |
*idtr = cpustat->idt.base;
|
|
Packit Service |
501009 |
|
|
Packit Service |
501009 |
return TRUE;
|
|
Packit Service |
501009 |
}
|
|
Packit Service |
501009 |
|
|
Packit Service |
501009 |
/*
|
|
Packit Service |
501009 |
* Check if current kaslr_offset/phys_base is for 1st kernel or 2nd kernel.
|
|
Packit Service |
501009 |
* If we are in 2nd kernel, get kaslr_offset/phys_base from vmcoreinfo.
|
|
Packit Service |
501009 |
*
|
|
Packit Service |
501009 |
* 1. Get command line and try to retrieve "elfcorehdr=" boot parameter
|
|
Packit Service |
501009 |
* 2. If "elfcorehdr=" is not found in command line, we are in 1st kernel.
|
|
Packit Service |
501009 |
* There is nothing to do.
|
|
Packit Service |
501009 |
* 3. If "elfcorehdr=" is found, we are in 2nd kernel. Find vmcoreinfo
|
|
Packit Service |
501009 |
* using "elfcorehdr=" and retrieve kaslr_offset/phys_base from vmcoreinfo.
|
|
Packit Service |
501009 |
*/
|
|
Packit Service |
501009 |
static int
|
|
Packit Service |
501009 |
get_kaslr_offset_from_vmcoreinfo(ulong orig_kaslr_offset,
|
|
Packit Service |
501009 |
ulong *kaslr_offset, ulong *phys_base)
|
|
Packit Service |
501009 |
{
|
|
Packit Service |
501009 |
ulong elfcorehdr_addr = 0;
|
|
Packit Service |
501009 |
ulong vmcoreinfo_addr;
|
|
Packit Service |
501009 |
int vmcoreinfo_len;
|
|
Packit Service |
501009 |
char *buf, *pos;
|
|
Packit Service |
501009 |
int ret = FALSE;
|
|
Packit Service |
501009 |
|
|
Packit Service |
501009 |
/* Find "elfcorehdr=" in the kernel boot parameter */
|
|
Packit Service |
501009 |
elfcorehdr_addr = get_elfcorehdr(orig_kaslr_offset);
|
|
Packit Service |
501009 |
if (!elfcorehdr_addr)
|
|
Packit Service |
501009 |
return FALSE;
|
|
Packit Service |
501009 |
|
|
Packit Service |
501009 |
/* Get vmcoreinfo from the address of "elfcorehdr=" */
|
|
Packit Service |
501009 |
if (!get_vmcoreinfo(elfcorehdr_addr, &vmcoreinfo_addr, &vmcoreinfo_len))
|
|
Packit Service |
501009 |
return FALSE;
|
|
Packit Service |
501009 |
|
|
Packit Service |
501009 |
if (!vmcoreinfo_len)
|
|
Packit Service |
501009 |
return FALSE;
|
|
Packit Service |
501009 |
|
|
Packit Service |
501009 |
if (CRASHDEBUG(1))
|
|
Packit Service |
501009 |
fprintf(fp, "Find vmcoreinfo in kdump memory\n");
|
|
Packit Service |
501009 |
|
|
Packit Service |
501009 |
buf = GETBUF(vmcoreinfo_len);
|
|
Packit Service |
501009 |
if (!readmem(vmcoreinfo_addr, PHYSADDR, buf, vmcoreinfo_len,
|
|
Packit Service |
501009 |
"vmcoreinfo", RETURN_ON_ERROR))
|
|
Packit Service |
501009 |
goto quit;
|
|
Packit Service |
501009 |
|
|
Packit Service |
501009 |
/* Get phys_base form vmcoreinfo */
|
|
Packit Service |
501009 |
pos = strstr(buf, "NUMBER(phys_base)=");
|
|
Packit Service |
501009 |
if (!pos)
|
|
Packit Service |
501009 |
goto quit;
|
|
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501009 |
*phys_base = strtoull(pos + strlen("NUMBER(phys_base)="), NULL, 0);
|
|
Packit Service |
501009 |
|
|
Packit Service |
501009 |
/* Get kaslr_offset form vmcoreinfo */
|
|
Packit Service |
501009 |
pos = strstr(buf, "KERNELOFFSET=");
|
|
Packit Service |
501009 |
if (!pos)
|
|
Packit Service |
501009 |
goto quit;
|
|
Packit Service |
501009 |
*kaslr_offset = strtoull(pos + strlen("KERNELOFFSET="), NULL, 16);
|
|
Packit Service |
501009 |
|
|
Packit Service |
501009 |
ret = TRUE;
|
|
Packit Service |
501009 |
|
|
Packit Service |
501009 |
quit:
|
|
Packit Service |
501009 |
FREEBUF(buf);
|
|
Packit Service |
501009 |
return ret;
|
|
Packit Service |
501009 |
}
|
|
Packit Service |
501009 |
|
|
Packit Service |
501009 |
/*
|
|
Packit Service |
501009 |
* Calculate kaslr_offset and phys_base
|
|
Packit Service |
501009 |
*
|
|
Packit Service |
501009 |
* kaslr_offset:
|
|
Packit Service |
501009 |
* The difference between original address in System.map or vmlinux and
|
|
Packit Service |
501009 |
* actual address placed randomly by kaslr feature. To be more accurate,
|
|
Packit Service |
501009 |
* kaslr_offset = actual address - original address
|
|
Packit Service |
501009 |
*
|
|
Packit Service |
501009 |
* phys_base:
|
|
Packit Service |
501009 |
* Physical address where the kerenel is placed. In other words, it's a
|
|
Packit Service |
501009 |
* physical address of __START_KERNEL_map. This is also decided randomly by
|
|
Packit Service |
501009 |
* kaslr.
|
|
Packit Service |
501009 |
*
|
|
Packit Service |
501009 |
* kaslr offset and phys_base are calculated as follows:
|
|
Packit Service |
501009 |
*
|
|
Packit Service |
501009 |
* kaslr_offset:
|
|
Packit Service |
501009 |
* 1) Get IDTR and CR3 value from the dump header.
|
|
Packit Service |
501009 |
* 2) Get a virtual address of IDT from IDTR value
|
|
Packit Service |
501009 |
* --- (A)
|
|
Packit Service |
501009 |
* 3) Translate (A) to physical address using CR3, the upper 52 bits
|
|
Packit Service |
501009 |
* of which points a top of page table.
|
|
Packit Service |
501009 |
* --- (B)
|
|
Packit Service |
501009 |
* 4) Get an address of vector0 (Devide Error) interrupt handler from
|
|
Packit Service |
501009 |
* IDT, which are pointed by (B).
|
|
Packit Service |
501009 |
* --- (C)
|
|
Packit Service |
501009 |
* 5) Get an address of symbol "divide_error" form vmlinux
|
|
Packit Service |
501009 |
* --- (D)
|
|
Packit Service |
501009 |
*
|
|
Packit Service |
501009 |
* Now we have two addresses:
|
|
Packit Service |
501009 |
* (C)-> Actual address of "divide_error"
|
|
Packit Service |
501009 |
* (D)-> Original address of "divide_error" in the vmlinux
|
|
Packit Service |
501009 |
*
|
|
Packit Service |
501009 |
* kaslr_offset can be calculated by the difference between these two
|
|
Packit Service |
501009 |
* value.
|
|
Packit Service |
501009 |
*
|
|
Packit Service |
501009 |
* phys_base;
|
|
Packit Service |
501009 |
* 1) Get IDT virtual address from vmlinux
|
|
Packit Service |
501009 |
* --- (E)
|
|
Packit Service |
501009 |
*
|
|
Packit Service |
501009 |
* So phys_base can be calculated using relationship of directly mapped
|
|
Packit Service |
501009 |
* address.
|
|
Packit Service |
501009 |
*
|
|
Packit Service |
501009 |
* phys_base =
|
|
Packit Service |
501009 |
* Physical address(B) -
|
|
Packit Service |
501009 |
* (Virtual address(E) + kaslr_offset - __START_KERNEL_map)
|
|
Packit Service |
501009 |
*
|
|
Packit Service |
501009 |
* Note that the address (A) cannot be used instead of (E) because (A) is
|
|
Packit Service |
501009 |
* not direct map address, it's a fixed map address.
|
|
Packit Service |
501009 |
*
|
|
Packit Service |
501009 |
* This solution works in most every case, but does not work in the
|
|
Packit Service |
501009 |
* following case.
|
|
Packit Service |
501009 |
*
|
|
Packit Service |
501009 |
* 1) If the dump is captured on early stage of kernel boot, IDTR points
|
|
Packit Service |
501009 |
* early IDT table(early_idts) instead of normal IDT(idt_table).
|
|
Packit Service |
501009 |
* 2) If the dump is captured whle kdump is working, IDTR points
|
|
Packit Service |
501009 |
* IDT table of 2nd kernel, not 1st kernel.
|
|
Packit Service |
501009 |
*
|
|
Packit Service |
501009 |
* Current implementation does not support the case 1), need
|
|
Packit Service |
501009 |
* enhancement in the future. For the case 2), get kaslr_offset and
|
|
Packit Service |
501009 |
* phys_base as follows.
|
|
Packit Service |
501009 |
*
|
|
Packit Service |
501009 |
* 1) Get kaslr_offset and phys_base using the above solution.
|
|
Packit Service |
501009 |
* 2) Get kernel boot parameter from "saved_command_line"
|
|
Packit Service |
501009 |
* 3) If "elfcorehdr=" is not included in boot parameter, we are in the
|
|
Packit Service |
501009 |
* first kernel, nothing to do any more.
|
|
Packit Service |
501009 |
* 4) If "elfcorehdr=" is included in boot parameter, we are in the 2nd
|
|
Packit Service |
501009 |
* kernel. Retrieve vmcoreinfo from address of "elfcorehdr=" and
|
|
Packit Service |
501009 |
* get kaslr_offset and phys_base from vmcoreinfo.
|
|
Packit Service |
501009 |
*/
|
|
Packit Service |
501009 |
#define PTI_USER_PGTABLE_BIT PAGE_SHIFT
|
|
Packit Service |
501009 |
#define PTI_USER_PGTABLE_MASK (1 << PTI_USER_PGTABLE_BIT)
|
|
Packit Service |
501009 |
#define CR3_PCID_MASK 0xFFFull
|
|
Packit Service |
501009 |
int
|
|
Packit Service |
2efe25 |
calc_kaslr_offset(ulong *ko, ulong *pb)
|
|
Packit Service |
501009 |
{
|
|
Packit Service |
501009 |
uint64_t cr3 = 0, idtr = 0, pgd = 0, idtr_paddr;
|
|
Packit Service |
501009 |
ulong divide_error_vmcore;
|
|
Packit Service |
2efe25 |
ulong kaslr_offset, phys_base;
|
|
Packit Service |
501009 |
ulong kaslr_offset_kdump, phys_base_kdump;
|
|
Packit Service |
501009 |
int ret = FALSE;
|
|
Packit Service |
501009 |
int verbose = CRASHDEBUG(1)? 1: 0;
|
|
Packit Service |
501009 |
|
|
Packit Service |
501009 |
if (!machine_type("X86_64"))
|
|
Packit Service |
501009 |
return FALSE;
|
|
Packit Service |
501009 |
|
|
Packit Service |
2efe25 |
retry:
|
|
Packit Service |
501009 |
if (SADUMP_DUMPFILE()) {
|
|
Packit Service |
501009 |
if (!sadump_get_cr3_idtr(&cr3, &idtr))
|
|
Packit Service |
501009 |
return FALSE;
|
|
Packit Service |
501009 |
} else if (QEMU_MEM_DUMP_NO_VMCOREINFO()) {
|
|
Packit Service |
501009 |
if (!qemu_get_cr3_idtr(&cr3, &idtr))
|
|
Packit Service |
501009 |
return FALSE;
|
|
Packit Service |
501009 |
} else if (VMSS_DUMPFILE()) {
|
|
Packit Service |
501009 |
if (!vmware_vmss_get_cr3_idtr(&cr3, &idtr))
|
|
Packit Service |
501009 |
return FALSE;
|
|
Packit Service |
501009 |
} else
|
|
Packit Service |
501009 |
return FALSE;
|
|
Packit Service |
501009 |
|
|
Packit Service |
501009 |
if (st->pti_init_vmlinux || st->kaiser_init_vmlinux)
|
|
Packit Service |
501009 |
pgd = cr3 & ~(CR3_PCID_MASK|PTI_USER_PGTABLE_MASK);
|
|
Packit Service |
501009 |
else
|
|
Packit Service |
501009 |
pgd = cr3 & ~CR3_PCID_MASK;
|
|
Packit Service |
501009 |
|
|
Packit Service |
501009 |
/*
|
|
Packit Service |
501009 |
* Set up for kvtop.
|
|
Packit Service |
501009 |
*
|
|
Packit Service |
501009 |
* calc_kaslr_offset() is called before machdep_init(PRE_GDB), so some
|
|
Packit Service |
501009 |
* variables are not initialized yet. Set up them here to call kvtop().
|
|
Packit Service |
501009 |
*
|
|
Packit Service |
501009 |
* TODO: XEN and 5-level is not supported
|
|
Packit Service |
501009 |
*/
|
|
Packit Service |
501009 |
vt->kernel_pgd[0] = pgd;
|
|
Packit Service |
501009 |
machdep->last_pgd_read = vt->kernel_pgd[0];
|
|
Packit Service |
501009 |
machdep->machspec->physical_mask_shift = __PHYSICAL_MASK_SHIFT_2_6;
|
|
Packit Service |
501009 |
machdep->machspec->pgdir_shift = PGDIR_SHIFT;
|
|
Packit Service |
501009 |
machdep->machspec->ptrs_per_pgd = PTRS_PER_PGD;
|
|
Packit Service |
501009 |
if (!readmem(pgd, PHYSADDR, machdep->pgd, PAGESIZE(),
|
|
Packit Service |
2efe25 |
"pgd", RETURN_ON_ERROR)) {
|
|
Packit Service |
2efe25 |
if (SADUMP_DUMPFILE())
|
|
Packit Service |
2efe25 |
goto retry;
|
|
Packit Service |
2efe25 |
else
|
|
Packit Service |
2efe25 |
goto quit;
|
|
Packit Service |
2efe25 |
}
|
|
Packit Service |
501009 |
|
|
Packit Service |
501009 |
/* Convert virtual address of IDT table to physical address */
|
|
Packit Service |
2efe25 |
if (!kvtop(NULL, idtr, &idtr_paddr, verbose)) {
|
|
Packit Service |
2efe25 |
if (SADUMP_DUMPFILE())
|
|
Packit Service |
2efe25 |
goto retry;
|
|
Packit Service |
2efe25 |
else
|
|
Packit Service |
2efe25 |
goto quit;
|
|
Packit Service |
2efe25 |
}
|
|
Packit Service |
501009 |
|
|
Packit Service |
501009 |
/* Now we can calculate kaslr_offset and phys_base */
|
|
Packit Service |
501009 |
divide_error_vmcore = get_vec0_addr(idtr_paddr);
|
|
Packit Service |
2efe25 |
kaslr_offset = divide_error_vmcore - st->divide_error_vmlinux;
|
|
Packit Service |
2efe25 |
phys_base = idtr_paddr -
|
|
Packit Service |
2efe25 |
(st->idt_table_vmlinux + kaslr_offset - __START_KERNEL_map);
|
|
Packit Service |
2efe25 |
|
|
Packit Service |
2efe25 |
if (SADUMP_DUMPFILE()) {
|
|
Packit Service |
2efe25 |
char buf[sizeof("Linux version")];
|
|
Packit Service |
2efe25 |
ulong linux_banner_paddr;
|
|
Packit Service |
2efe25 |
|
|
Packit Service |
2efe25 |
if (!kvtop(NULL,
|
|
Packit Service |
2efe25 |
st->linux_banner_vmlinux + kaslr_offset,
|
|
Packit Service |
2efe25 |
&linux_banner_paddr,
|
|
Packit Service |
2efe25 |
verbose))
|
|
Packit Service |
2efe25 |
goto retry;
|
|
Packit Service |
2efe25 |
|
|
Packit Service |
2efe25 |
if (!readmem(linux_banner_paddr,
|
|
Packit Service |
2efe25 |
PHYSADDR,
|
|
Packit Service |
2efe25 |
buf,
|
|
Packit Service |
2efe25 |
sizeof(buf),
|
|
Packit Service |
2efe25 |
"linux_banner",
|
|
Packit Service |
2efe25 |
RETURN_ON_ERROR))
|
|
Packit Service |
2efe25 |
goto retry;
|
|
Packit Service |
2efe25 |
|
|
Packit Service |
2efe25 |
if (!STRNEQ(buf, "Linux version"))
|
|
Packit Service |
2efe25 |
goto retry;
|
|
Packit Service |
2efe25 |
}
|
|
Packit Service |
501009 |
|
|
Packit Service |
501009 |
if (CRASHDEBUG(1)) {
|
|
Packit Service |
501009 |
fprintf(fp, "calc_kaslr_offset: idtr=%lx\n", idtr);
|
|
Packit Service |
501009 |
fprintf(fp, "calc_kaslr_offset: pgd=%lx\n", pgd);
|
|
Packit Service |
501009 |
fprintf(fp, "calc_kaslr_offset: idtr(phys)=%lx\n", idtr_paddr);
|
|
Packit Service |
501009 |
fprintf(fp, "calc_kaslr_offset: divide_error(vmlinux): %lx\n",
|
|
Packit Service |
501009 |
st->divide_error_vmlinux);
|
|
Packit Service |
501009 |
fprintf(fp, "calc_kaslr_offset: divide_error(vmcore): %lx\n",
|
|
Packit Service |
501009 |
divide_error_vmcore);
|
|
Packit Service |
501009 |
}
|
|
Packit Service |
501009 |
|
|
Packit Service |
501009 |
/*
|
|
Packit Service |
501009 |
* Check if current kaslr_offset/phys_base is for 1st kernel or 2nd
|
|
Packit Service |
501009 |
* kernel. If we are in 2nd kernel, get kaslr_offset/phys_base
|
|
Packit Service |
501009 |
* from vmcoreinfo
|
|
Packit Service |
501009 |
*/
|
|
Packit Service |
501009 |
if (get_kaslr_offset_from_vmcoreinfo(
|
|
Packit Service |
2efe25 |
kaslr_offset, &kaslr_offset_kdump, &phys_base_kdump)) {
|
|
Packit Service |
2efe25 |
kaslr_offset = kaslr_offset_kdump;
|
|
Packit Service |
2efe25 |
phys_base = phys_base_kdump;
|
|
Packit Service |
501009 |
} else if (CRASHDEBUG(1)) {
|
|
Packit Service |
501009 |
fprintf(fp, "kaslr_helper: failed to determine which kernel was running at crash,\n");
|
|
Packit Service |
501009 |
fprintf(fp, "kaslr_helper: asssuming the kdump 1st kernel.\n");
|
|
Packit Service |
501009 |
}
|
|
Packit Service |
501009 |
|
|
Packit Service |
501009 |
if (CRASHDEBUG(1)) {
|
|
Packit Service |
501009 |
fprintf(fp, "calc_kaslr_offset: kaslr_offset=%lx\n",
|
|
Packit Service |
2efe25 |
kaslr_offset);
|
|
Packit Service |
2efe25 |
fprintf(fp, "calc_kaslr_offset: phys_base=%lx\n", phys_base);
|
|
Packit Service |
501009 |
}
|
|
Packit Service |
501009 |
|
|
Packit Service |
2efe25 |
*ko = kaslr_offset;
|
|
Packit Service |
2efe25 |
*pb = phys_base;
|
|
Packit Service |
2efe25 |
|
|
Packit Service |
501009 |
ret = TRUE;
|
|
Packit Service |
501009 |
quit:
|
|
Packit Service |
501009 |
vt->kernel_pgd[0] = 0;
|
|
Packit Service |
501009 |
machdep->last_pgd_read = 0;
|
|
Packit Service |
501009 |
return ret;
|
|
Packit Service |
501009 |
}
|
|
Packit Service |
501009 |
#else
|
|
Packit Service |
501009 |
int
|
|
Packit Service |
501009 |
calc_kaslr_offset(ulong *kaslr_offset, ulong *phys_page)
|
|
Packit Service |
501009 |
{
|
|
Packit Service |
501009 |
return FALSE;
|
|
Packit Service |
501009 |
}
|
|
Packit Service |
501009 |
#endif /* X86_64 */
|