mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-12-22 18:44:44 +08:00
adb5680b8d
lib/kaslr.c is used by both the main kernel and the boot stub. It
includes asm/io.h which is supposed to be used in the main kernel. It
leads to build warnings like this with clang 13:
warning: implicit declaration of function 'outl' is invalid in C99 [-Wimplicit-function-declaration]
Replace <asm/io.h> with <asm/shared/io.h> which is suitable for both
cases.
Fixes: 1e8f93e183 ("x86: Consolidate port I/O helpers")
Reported-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lore.kernel.org/r/20220410200025.3stf4jjvwfe5oxew@box.shutemov.name
99 lines
2.2 KiB
C
99 lines
2.2 KiB
C
// SPDX-License-Identifier: GPL-2.0
|
|
/*
|
|
* Entropy functions used on early boot for KASLR base and memory
|
|
* randomization. The base randomization is done in the compressed
|
|
* kernel and memory randomization is done early when the regular
|
|
* kernel starts. This file is included in the compressed kernel and
|
|
* normally linked in the regular.
|
|
*/
|
|
#include <asm/asm.h>
|
|
#include <asm/kaslr.h>
|
|
#include <asm/msr.h>
|
|
#include <asm/archrandom.h>
|
|
#include <asm/e820/api.h>
|
|
#include <asm/shared/io.h>
|
|
|
|
/*
|
|
* When built for the regular kernel, several functions need to be stubbed out
|
|
* or changed to their regular kernel equivalent.
|
|
*/
|
|
#ifndef KASLR_COMPRESSED_BOOT
|
|
#include <asm/cpufeature.h>
|
|
#include <asm/setup.h>
|
|
|
|
#define debug_putstr(v) early_printk("%s", v)
|
|
#define has_cpuflag(f) boot_cpu_has(f)
|
|
#define get_boot_seed() kaslr_offset()
|
|
#endif
|
|
|
|
#define I8254_PORT_CONTROL 0x43
|
|
#define I8254_PORT_COUNTER0 0x40
|
|
#define I8254_CMD_READBACK 0xC0
|
|
#define I8254_SELECT_COUNTER0 0x02
|
|
#define I8254_STATUS_NOTREADY 0x40
|
|
static inline u16 i8254(void)
|
|
{
|
|
u16 status, timer;
|
|
|
|
do {
|
|
outb(I8254_CMD_READBACK | I8254_SELECT_COUNTER0,
|
|
I8254_PORT_CONTROL);
|
|
status = inb(I8254_PORT_COUNTER0);
|
|
timer = inb(I8254_PORT_COUNTER0);
|
|
timer |= inb(I8254_PORT_COUNTER0) << 8;
|
|
} while (status & I8254_STATUS_NOTREADY);
|
|
|
|
return timer;
|
|
}
|
|
|
|
unsigned long kaslr_get_random_long(const char *purpose)
|
|
{
|
|
#ifdef CONFIG_X86_64
|
|
const unsigned long mix_const = 0x5d6008cbf3848dd3UL;
|
|
#else
|
|
const unsigned long mix_const = 0x3f39e593UL;
|
|
#endif
|
|
unsigned long raw, random = get_boot_seed();
|
|
bool use_i8254 = true;
|
|
|
|
if (purpose) {
|
|
debug_putstr(purpose);
|
|
debug_putstr(" KASLR using");
|
|
}
|
|
|
|
if (has_cpuflag(X86_FEATURE_RDRAND)) {
|
|
if (purpose)
|
|
debug_putstr(" RDRAND");
|
|
if (rdrand_long(&raw)) {
|
|
random ^= raw;
|
|
use_i8254 = false;
|
|
}
|
|
}
|
|
|
|
if (has_cpuflag(X86_FEATURE_TSC)) {
|
|
if (purpose)
|
|
debug_putstr(" RDTSC");
|
|
raw = rdtsc();
|
|
|
|
random ^= raw;
|
|
use_i8254 = false;
|
|
}
|
|
|
|
if (use_i8254) {
|
|
if (purpose)
|
|
debug_putstr(" i8254");
|
|
random ^= i8254();
|
|
}
|
|
|
|
/* Circular multiply for better bit diffusion */
|
|
asm(_ASM_MUL "%3"
|
|
: "=a" (random), "=d" (raw)
|
|
: "a" (random), "rm" (mix_const));
|
|
random += raw;
|
|
|
|
if (purpose)
|
|
debug_putstr("...\n");
|
|
|
|
return random;
|
|
}
|