Merge branch 'x86-kaslr-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 kernel address space randomization support from Peter Anvin: "This enables kernel address space randomization for x86" * 'x86-kaslr-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86, kaslr: Clarify RANDOMIZE_BASE_MAX_OFFSET x86, kaslr: Remove unused including <linux/version.h> x86, kaslr: Use char array to gain sizeof sanity x86, kaslr: Add a circular multiply for better bit diffusion x86, kaslr: Mix entropy sources together as needed x86/relocs: Add percpu fixup for GNU ld 2.23 x86, boot: Rename get_flags() and check_flags() to *_cpuflags() x86, kaslr: Raise the maximum virtual address to -1 GiB on x86_64 x86, kaslr: Report kernel offset on panic x86, kaslr: Select random position from e820 maps x86, kaslr: Provide randomness functions x86, kaslr: Return location from decompress_kernel x86, boot: Move CPU flags out of cpucheck x86, relocs: Add more per-cpu gold special cases
This commit is contained in:
Linus Torvalds
commit
f4bcd8ccdd
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|
@ -2017,6 +2017,10 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
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noapic [SMP,APIC] Tells the kernel to not make use of any
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IOAPICs that may be present in the system.
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nokaslr [X86]
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Disable kernel base offset ASLR (Address Space
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Layout Randomization) if built into the kernel.
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noautogroup Disable scheduler automatic task group creation.
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nobats [PPC] Do not use BATs for mapping kernel lowmem
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|
|
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@ -1693,16 +1693,67 @@ config RELOCATABLE
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Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
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it has been loaded at and the compile time physical address
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(CONFIG_PHYSICAL_START) is ignored.
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(CONFIG_PHYSICAL_START) is used as the minimum location.
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# Relocation on x86-32 needs some additional build support
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config RANDOMIZE_BASE
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bool "Randomize the address of the kernel image"
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depends on RELOCATABLE
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depends on !HIBERNATION
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default n
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---help---
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Randomizes the physical and virtual address at which the
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kernel image is decompressed, as a security feature that
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deters exploit attempts relying on knowledge of the location
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of kernel internals.
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Entropy is generated using the RDRAND instruction if it is
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supported. If RDTSC is supported, it is used as well. If
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neither RDRAND nor RDTSC are supported, then randomness is
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read from the i8254 timer.
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The kernel will be offset by up to RANDOMIZE_BASE_MAX_OFFSET,
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and aligned according to PHYSICAL_ALIGN. Since the kernel is
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built using 2GiB addressing, and PHYSICAL_ALGIN must be at a
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minimum of 2MiB, only 10 bits of entropy is theoretically
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possible. At best, due to page table layouts, 64-bit can use
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9 bits of entropy and 32-bit uses 8 bits.
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If unsure, say N.
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config RANDOMIZE_BASE_MAX_OFFSET
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hex "Maximum kASLR offset allowed" if EXPERT
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depends on RANDOMIZE_BASE
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range 0x0 0x20000000 if X86_32
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default "0x20000000" if X86_32
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range 0x0 0x40000000 if X86_64
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default "0x40000000" if X86_64
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---help---
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The lesser of RANDOMIZE_BASE_MAX_OFFSET and available physical
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memory is used to determine the maximal offset in bytes that will
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be applied to the kernel when kernel Address Space Layout
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Randomization (kASLR) is active. This must be a multiple of
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PHYSICAL_ALIGN.
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On 32-bit this is limited to 512MiB by page table layouts. The
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default is 512MiB.
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On 64-bit this is limited by how the kernel fixmap page table is
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positioned, so this cannot be larger than 1GiB currently. Without
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RANDOMIZE_BASE, there is a 512MiB to 1.5GiB split between kernel
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and modules. When RANDOMIZE_BASE_MAX_OFFSET is above 512MiB, the
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modules area will shrink to compensate, up to the current maximum
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1GiB to 1GiB split. The default is 1GiB.
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If unsure, leave at the default value.
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# Relocation on x86 needs some additional build support
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config X86_NEED_RELOCS
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def_bool y
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depends on X86_32 && RELOCATABLE
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depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE)
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config PHYSICAL_ALIGN
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hex "Alignment value to which kernel should be aligned"
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default "0x1000000"
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default "0x200000"
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range 0x2000 0x1000000 if X86_32
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range 0x200000 0x1000000 if X86_64
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---help---
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|
|
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|
@ -20,7 +20,7 @@ targets := vmlinux.bin setup.bin setup.elf bzImage
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targets += fdimage fdimage144 fdimage288 image.iso mtools.conf
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subdir- := compressed
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setup-y += a20.o bioscall.o cmdline.o copy.o cpu.o cpucheck.o
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setup-y += a20.o bioscall.o cmdline.o copy.o cpu.o cpuflags.o cpucheck.o
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setup-y += early_serial_console.o edd.o header.o main.o mca.o memory.o
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setup-y += pm.o pmjump.o printf.o regs.o string.o tty.o video.o
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setup-y += video-mode.o version.o
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|
|
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|
|
@ -26,9 +26,8 @@
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|||
#include <asm/boot.h>
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#include <asm/setup.h>
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#include "bitops.h"
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#include <asm/cpufeature.h>
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#include <asm/processor-flags.h>
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#include "ctype.h"
|
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#include "cpuflags.h"
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|
||||
/* Useful macros */
|
||||
#define BUILD_BUG_ON(condition) ((void)sizeof(char[1 - 2*!!(condition)]))
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|
|
@ -307,14 +306,7 @@ static inline int cmdline_find_option_bool(const char *option)
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return __cmdline_find_option_bool(cmd_line_ptr, option);
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||||
}
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|
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|
||||
/* cpu.c, cpucheck.c */
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||||
struct cpu_features {
|
||||
int level; /* Family, or 64 for x86-64 */
|
||||
int model;
|
||||
u32 flags[NCAPINTS];
|
||||
};
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||||
extern struct cpu_features cpu;
|
||||
int check_cpu(int *cpu_level_ptr, int *req_level_ptr, u32 **err_flags_ptr);
|
||||
int validate_cpu(void);
|
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|
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|
|
|
|||
|
|
@ -28,7 +28,7 @@ HOST_EXTRACFLAGS += -I$(srctree)/tools/include
|
|||
|
||||
VMLINUX_OBJS = $(obj)/vmlinux.lds $(obj)/head_$(BITS).o $(obj)/misc.o \
|
||||
$(obj)/string.o $(obj)/cmdline.o $(obj)/early_serial_console.o \
|
||||
$(obj)/piggy.o
|
||||
$(obj)/piggy.o $(obj)/cpuflags.o $(obj)/aslr.o
|
||||
|
||||
$(obj)/eboot.o: KBUILD_CFLAGS += -fshort-wchar -mno-red-zone
|
||||
|
||||
|
|
|
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|
|
@ -0,0 +1,316 @@
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|||
#include "misc.h"
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||||
|
||||
#ifdef CONFIG_RANDOMIZE_BASE
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#include <asm/msr.h>
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#include <asm/archrandom.h>
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||||
#include <asm/e820.h>
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||||
|
||||
#include <generated/compile.h>
|
||||
#include <linux/module.h>
|
||||
#include <linux/uts.h>
|
||||
#include <linux/utsname.h>
|
||||
#include <generated/utsrelease.h>
|
||||
|
||||
/* Simplified build-specific string for starting entropy. */
|
||||
static const char build_str[] = UTS_RELEASE " (" LINUX_COMPILE_BY "@"
|
||||
LINUX_COMPILE_HOST ") (" LINUX_COMPILER ") " UTS_VERSION;
|
||||
|
||||
#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_PORT_CONTROL,
|
||||
I8254_CMD_READBACK | I8254_SELECT_COUNTER0);
|
||||
status = inb(I8254_PORT_COUNTER0);
|
||||
timer = inb(I8254_PORT_COUNTER0);
|
||||
timer |= inb(I8254_PORT_COUNTER0) << 8;
|
||||
} while (status & I8254_STATUS_NOTREADY);
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||||
|
||||
return timer;
|
||||
}
|
||||
|
||||
static unsigned long rotate_xor(unsigned long hash, const void *area,
|
||||
size_t size)
|
||||
{
|
||||
size_t i;
|
||||
unsigned long *ptr = (unsigned long *)area;
|
||||
|
||||
for (i = 0; i < size / sizeof(hash); i++) {
|
||||
/* Rotate by odd number of bits and XOR. */
|
||||
hash = (hash << ((sizeof(hash) * 8) - 7)) | (hash >> 7);
|
||||
hash ^= ptr[i];
|
||||
}
|
||||
|
||||
return hash;
|
||||
}
|
||||
|
||||
/* Attempt to create a simple but unpredictable starting entropy. */
|
||||
static unsigned long get_random_boot(void)
|
||||
{
|
||||
unsigned long hash = 0;
|
||||
|
||||
hash = rotate_xor(hash, build_str, sizeof(build_str));
|
||||
hash = rotate_xor(hash, real_mode, sizeof(*real_mode));
|
||||
|
||||
return hash;
|
||||
}
|
||||
|
||||
static unsigned long get_random_long(void)
|
||||
{
|
||||
#ifdef CONFIG_X86_64
|
||||
const unsigned long mix_const = 0x5d6008cbf3848dd3UL;
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||||
#else
|
||||
const unsigned long mix_const = 0x3f39e593UL;
|
||||
#endif
|
||||
unsigned long raw, random = get_random_boot();
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bool use_i8254 = true;
|
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|
||||
debug_putstr("KASLR using");
|
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|
||||
if (has_cpuflag(X86_FEATURE_RDRAND)) {
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||||
debug_putstr(" RDRAND");
|
||||
if (rdrand_long(&raw)) {
|
||||
random ^= raw;
|
||||
use_i8254 = false;
|
||||
}
|
||||
}
|
||||
|
||||
if (has_cpuflag(X86_FEATURE_TSC)) {
|
||||
debug_putstr(" RDTSC");
|
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rdtscll(raw);
|
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|
||||
random ^= raw;
|
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use_i8254 = false;
|
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}
|
||||
|
||||
if (use_i8254) {
|
||||
debug_putstr(" i8254");
|
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random ^= i8254();
|
||||
}
|
||||
|
||||
/* Circular multiply for better bit diffusion */
|
||||
asm("mul %3"
|
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: "=a" (random), "=d" (raw)
|
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: "a" (random), "rm" (mix_const));
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random += raw;
|
||||
|
||||
debug_putstr("...\n");
|
||||
|
||||
return random;
|
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}
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|
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struct mem_vector {
|
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unsigned long start;
|
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unsigned long size;
|
||||
};
|
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|
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#define MEM_AVOID_MAX 5
|
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struct mem_vector mem_avoid[MEM_AVOID_MAX];
|
||||
|
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static bool mem_contains(struct mem_vector *region, struct mem_vector *item)
|
||||
{
|
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/* Item at least partially before region. */
|
||||
if (item->start < region->start)
|
||||
return false;
|
||||
/* Item at least partially after region. */
|
||||
if (item->start + item->size > region->start + region->size)
|
||||
return false;
|
||||
return true;
|
||||
}
|
||||
|
||||
static bool mem_overlaps(struct mem_vector *one, struct mem_vector *two)
|
||||
{
|
||||
/* Item one is entirely before item two. */
|
||||
if (one->start + one->size <= two->start)
|
||||
return false;
|
||||
/* Item one is entirely after item two. */
|
||||
if (one->start >= two->start + two->size)
|
||||
return false;
|
||||
return true;
|
||||
}
|
||||
|
||||
static void mem_avoid_init(unsigned long input, unsigned long input_size,
|
||||
unsigned long output, unsigned long output_size)
|
||||
{
|
||||
u64 initrd_start, initrd_size;
|
||||
u64 cmd_line, cmd_line_size;
|
||||
unsigned long unsafe, unsafe_len;
|
||||
char *ptr;
|
||||
|
||||
/*
|
||||
* Avoid the region that is unsafe to overlap during
|
||||
* decompression (see calculations at top of misc.c).
|
||||
*/
|
||||
unsafe_len = (output_size >> 12) + 32768 + 18;
|
||||
unsafe = (unsigned long)input + input_size - unsafe_len;
|
||||
mem_avoid[0].start = unsafe;
|
||||
mem_avoid[0].size = unsafe_len;
|
||||
|
||||
/* Avoid initrd. */
|
||||
initrd_start = (u64)real_mode->ext_ramdisk_image << 32;
|
||||
initrd_start |= real_mode->hdr.ramdisk_image;
|
||||
initrd_size = (u64)real_mode->ext_ramdisk_size << 32;
|
||||
initrd_size |= real_mode->hdr.ramdisk_size;
|
||||
mem_avoid[1].start = initrd_start;
|
||||
mem_avoid[1].size = initrd_size;
|
||||
|
||||
/* Avoid kernel command line. */
|
||||
cmd_line = (u64)real_mode->ext_cmd_line_ptr << 32;
|
||||
cmd_line |= real_mode->hdr.cmd_line_ptr;
|
||||
/* Calculate size of cmd_line. */
|
||||
ptr = (char *)(unsigned long)cmd_line;
|
||||
for (cmd_line_size = 0; ptr[cmd_line_size++]; )
|
||||
;
|
||||
mem_avoid[2].start = cmd_line;
|
||||
mem_avoid[2].size = cmd_line_size;
|
||||
|
||||
/* Avoid heap memory. */
|
||||
mem_avoid[3].start = (unsigned long)free_mem_ptr;
|
||||
mem_avoid[3].size = BOOT_HEAP_SIZE;
|
||||
|
||||
/* Avoid stack memory. */
|
||||
mem_avoid[4].start = (unsigned long)free_mem_end_ptr;
|
||||
mem_avoid[4].size = BOOT_STACK_SIZE;
|
||||
}
|
||||
|
||||
/* Does this memory vector overlap a known avoided area? */
|
||||
bool mem_avoid_overlap(struct mem_vector *img)
|
||||
{
|
||||
int i;
|
||||
|
||||
for (i = 0; i < MEM_AVOID_MAX; i++) {
|
||||
if (mem_overlaps(img, &mem_avoid[i]))
|
||||
return true;
|
||||
}
|
||||
|
||||
return false;
|
||||
}
|
||||
|
||||
unsigned long slots[CONFIG_RANDOMIZE_BASE_MAX_OFFSET / CONFIG_PHYSICAL_ALIGN];
|
||||
unsigned long slot_max = 0;
|
||||
|
||||
static void slots_append(unsigned long addr)
|
||||
{
|
||||
/* Overflowing the slots list should be impossible. */
|
||||
if (slot_max >= CONFIG_RANDOMIZE_BASE_MAX_OFFSET /
|
||||
CONFIG_PHYSICAL_ALIGN)
|
||||
return;
|
||||
|
||||
slots[slot_max++] = addr;
|
||||
}
|
||||
|
||||
static unsigned long slots_fetch_random(void)
|
||||
{
|
||||
/* Handle case of no slots stored. */
|
||||
if (slot_max == 0)
|
||||
return 0;
|
||||
|
||||
return slots[get_random_long() % slot_max];
|
||||
}
|
||||
|
||||
static void process_e820_entry(struct e820entry *entry,
|
||||
unsigned long minimum,
|
||||
unsigned long image_size)
|
||||
{
|
||||
struct mem_vector region, img;
|
||||
|
||||
/* Skip non-RAM entries. */
|
||||
if (entry->type != E820_RAM)
|
||||
return;
|
||||
|
||||
/* Ignore entries entirely above our maximum. */
|
||||
if (entry->addr >= CONFIG_RANDOMIZE_BASE_MAX_OFFSET)
|
||||
return;
|
||||
|
||||
/* Ignore entries entirely below our minimum. */
|
||||
if (entry->addr + entry->size < minimum)
|
||||
return;
|
||||
|
||||
region.start = entry->addr;
|
||||
region.size = entry->size;
|
||||
|
||||
/* Potentially raise address to minimum location. */
|
||||
if (region.start < minimum)
|
||||
region.start = minimum;
|
||||
|
||||
/* Potentially raise address to meet alignment requirements. */
|
||||
region.start = ALIGN(region.start, CONFIG_PHYSICAL_ALIGN);
|
||||
|
||||
/* Did we raise the address above the bounds of this e820 region? */
|
||||
if (region.start > entry->addr + entry->size)
|
||||
return;
|
||||
|
||||
/* Reduce size by any delta from the original address. */
|
||||
region.size -= region.start - entry->addr;
|
||||
|
||||
/* Reduce maximum size to fit end of image within maximum limit. */
|
||||
if (region.start + region.size > CONFIG_RANDOMIZE_BASE_MAX_OFFSET)
|
||||
region.size = CONFIG_RANDOMIZE_BASE_MAX_OFFSET - region.start;
|
||||
|
||||
/* Walk each aligned slot and check for avoided areas. */
|
||||
for (img.start = region.start, img.size = image_size ;
|
||||
mem_contains(®ion, &img) ;
|
||||
img.start += CONFIG_PHYSICAL_ALIGN) {
|
||||
if (mem_avoid_overlap(&img))
|
||||
continue;
|
||||
slots_append(img.start);
|
||||
}
|
||||
}
|
||||
|
||||
static unsigned long find_random_addr(unsigned long minimum,
|
||||
unsigned long size)
|
||||
{
|
||||
int i;
|
||||
unsigned long addr;
|
||||
|
||||
/* Make sure minimum is aligned. */
|
||||
minimum = ALIGN(minimum, CONFIG_PHYSICAL_ALIGN);
|
||||
|
||||
/* Verify potential e820 positions, appending to slots list. */
|
||||
for (i = 0; i < real_mode->e820_entries; i++) {
|
||||
process_e820_entry(&real_mode->e820_map[i], minimum, size);
|
||||
}
|
||||
|
||||
return slots_fetch_random();
|
||||
}
|
||||
|
||||
unsigned char *choose_kernel_location(unsigned char *input,
|
||||
unsigned long input_size,
|
||||
unsigned char *output,
|
||||
unsigned long output_size)
|
||||
{
|
||||
unsigned long choice = (unsigned long)output;
|
||||
unsigned long random;
|
||||
|
||||
if (cmdline_find_option_bool("nokaslr")) {
|
||||
debug_putstr("KASLR disabled...\n");
|
||||
goto out;
|
||||
}
|
||||
|
||||
/* Record the various known unsafe memory ranges. */
|
||||
mem_avoid_init((unsigned long)input, input_size,
|
||||
(unsigned long)output, output_size);
|
||||
|
||||
/* Walk e820 and find a random address. */
|
||||
random = find_random_addr(choice, output_size);
|
||||
if (!random) {
|
||||
debug_putstr("KASLR could not find suitable E820 region...\n");
|
||||
goto out;
|
||||
}
|
||||
|
||||
/* Always enforce the minimum. */
|
||||
if (random < choice)
|
||||
goto out;
|
||||
|
||||
choice = random;
|
||||
out:
|
||||
return (unsigned char *)choice;
|
||||
}
|
||||
|
||||
#endif /* CONFIG_RANDOMIZE_BASE */
|
||||
|
|
@ -1,6 +1,6 @@
|
|||
#include "misc.h"
|
||||
|
||||
#ifdef CONFIG_EARLY_PRINTK
|
||||
#if CONFIG_EARLY_PRINTK || CONFIG_RANDOMIZE_BASE
|
||||
|
||||
static unsigned long fs;
|
||||
static inline void set_fs(unsigned long seg)
|
||||
|
|
|
|||
|
|
@ -0,0 +1,12 @@
|
|||
#ifdef CONFIG_RANDOMIZE_BASE
|
||||
|
||||
#include "../cpuflags.c"
|
||||
|
||||
bool has_cpuflag(int flag)
|
||||
{
|
||||
get_cpuflags();
|
||||
|
||||
return test_bit(flag, cpu.flags);
|
||||
}
|
||||
|
||||
#endif
|
||||
|
|
@ -117,9 +117,11 @@ preferred_addr:
|
|||
addl %eax, %ebx
|
||||
notl %eax
|
||||
andl %eax, %ebx
|
||||
#else
|
||||
movl $LOAD_PHYSICAL_ADDR, %ebx
|
||||
cmpl $LOAD_PHYSICAL_ADDR, %ebx
|
||||
jge 1f
|
||||
#endif
|
||||
movl $LOAD_PHYSICAL_ADDR, %ebx
|
||||
1:
|
||||
|
||||
/* Target address to relocate to for decompression */
|
||||
addl $z_extract_offset, %ebx
|
||||
|
|
@ -191,14 +193,14 @@ relocated:
|
|||
leal boot_heap(%ebx), %eax
|
||||
pushl %eax /* heap area */
|
||||
pushl %esi /* real mode pointer */
|
||||
call decompress_kernel
|
||||
call decompress_kernel /* returns kernel location in %eax */
|
||||
addl $24, %esp
|
||||
|
||||
/*
|
||||
* Jump to the decompressed kernel.
|
||||
*/
|
||||
xorl %ebx, %ebx
|
||||
jmp *%ebp
|
||||
jmp *%eax
|
||||
|
||||
/*
|
||||
* Stack and heap for uncompression
|
||||
|
|
|
|||
|
|
@ -94,9 +94,11 @@ ENTRY(startup_32)
|
|||
addl %eax, %ebx
|
||||
notl %eax
|
||||
andl %eax, %ebx
|
||||
#else
|
||||
movl $LOAD_PHYSICAL_ADDR, %ebx
|
||||
cmpl $LOAD_PHYSICAL_ADDR, %ebx
|
||||
jge 1f
|
||||
#endif
|
||||
movl $LOAD_PHYSICAL_ADDR, %ebx
|
||||
1:
|
||||
|
||||
/* Target address to relocate to for decompression */
|
||||
addl $z_extract_offset, %ebx
|
||||
|
|
@ -269,9 +271,11 @@ preferred_addr:
|
|||
addq %rax, %rbp
|
||||
notq %rax
|
||||
andq %rax, %rbp
|
||||
#else
|
||||
movq $LOAD_PHYSICAL_ADDR, %rbp
|
||||
cmpq $LOAD_PHYSICAL_ADDR, %rbp
|
||||
jge 1f
|
||||
#endif
|
||||
movq $LOAD_PHYSICAL_ADDR, %rbp
|
||||
1:
|
||||
|
||||
/* Target address to relocate to for decompression */
|
||||
leaq z_extract_offset(%rbp), %rbx
|
||||
|
|
@ -339,13 +343,13 @@ relocated:
|
|||
movl $z_input_len, %ecx /* input_len */
|
||||
movq %rbp, %r8 /* output target address */
|
||||
movq $z_output_len, %r9 /* decompressed length */
|
||||
call decompress_kernel
|
||||
call decompress_kernel /* returns kernel location in %rax */
|
||||
popq %rsi
|
||||
|
||||
/*
|
||||
* Jump to the decompressed kernel.
|
||||
*/
|
||||
jmp *%rbp
|
||||
jmp *%rax
|
||||
|
||||
.code32
|
||||
no_longmode:
|
||||
|
|
|
|||
|
|
@ -112,14 +112,8 @@ struct boot_params *real_mode; /* Pointer to real-mode data */
|
|||
void *memset(void *s, int c, size_t n);
|
||||
void *memcpy(void *dest, const void *src, size_t n);
|
||||
|
||||
#ifdef CONFIG_X86_64
|
||||
#define memptr long
|
||||
#else
|
||||
#define memptr unsigned
|
||||
#endif
|
||||
|
||||
static memptr free_mem_ptr;
|
||||
static memptr free_mem_end_ptr;
|
||||
memptr free_mem_ptr;
|
||||
memptr free_mem_end_ptr;
|
||||
|
||||
static char *vidmem;
|
||||
static int vidport;
|
||||
|
|
@ -395,7 +389,7 @@ static void parse_elf(void *output)
|
|||
free(phdrs);
|
||||
}
|
||||
|
||||
asmlinkage void decompress_kernel(void *rmode, memptr heap,
|
||||
asmlinkage void *decompress_kernel(void *rmode, memptr heap,
|
||||
unsigned char *input_data,
|
||||
unsigned long input_len,
|
||||
unsigned char *output,
|
||||
|
|
@ -422,6 +416,10 @@ asmlinkage void decompress_kernel(void *rmode, memptr heap,
|
|||
free_mem_ptr = heap; /* Heap */
|
||||
free_mem_end_ptr = heap + BOOT_HEAP_SIZE;
|
||||
|
||||
output = choose_kernel_location(input_data, input_len,
|
||||
output, output_len);
|
||||
|
||||
/* Validate memory location choices. */
|
||||
if ((unsigned long)output & (MIN_KERNEL_ALIGN - 1))
|
||||
error("Destination address inappropriately aligned");
|
||||
#ifdef CONFIG_X86_64
|
||||
|
|
@ -441,5 +439,5 @@ asmlinkage void decompress_kernel(void *rmode, memptr heap,
|
|||
parse_elf(output);
|
||||
handle_relocations(output, output_len);
|
||||
debug_putstr("done.\nBooting the kernel.\n");
|
||||
return;
|
||||
return output;
|
||||
}
|
||||
|
|
|
|||
|
|
@ -23,7 +23,15 @@
|
|||
#define BOOT_BOOT_H
|
||||
#include "../ctype.h"
|
||||
|
||||
#ifdef CONFIG_X86_64
|
||||
#define memptr long
|
||||
#else
|
||||
#define memptr unsigned
|
||||
#endif
|
||||
|
||||
/* misc.c */
|
||||
extern memptr free_mem_ptr;
|
||||
extern memptr free_mem_end_ptr;
|
||||
extern struct boot_params *real_mode; /* Pointer to real-mode data */
|
||||
void __putstr(const char *s);
|
||||
#define error_putstr(__x) __putstr(__x)
|
||||
|
|
@ -39,23 +47,40 @@ static inline void debug_putstr(const char *s)
|
|||
|
||||
#endif
|
||||
|
||||
#ifdef CONFIG_EARLY_PRINTK
|
||||
|
||||
#if CONFIG_EARLY_PRINTK || CONFIG_RANDOMIZE_BASE
|
||||
/* cmdline.c */
|
||||
int cmdline_find_option(const char *option, char *buffer, int bufsize);
|
||||
int cmdline_find_option_bool(const char *option);
|
||||
#endif
|
||||
|
||||
|
||||
#if CONFIG_RANDOMIZE_BASE
|
||||
/* aslr.c */
|
||||
unsigned char *choose_kernel_location(unsigned char *input,
|
||||
unsigned long input_size,
|
||||
unsigned char *output,
|
||||
unsigned long output_size);
|
||||
/* cpuflags.c */
|
||||
bool has_cpuflag(int flag);
|
||||
#else
|
||||
static inline
|
||||
unsigned char *choose_kernel_location(unsigned char *input,
|
||||
unsigned long input_size,
|
||||
unsigned char *output,
|
||||
unsigned long output_size)
|
||||
{
|
||||
return output;
|
||||
}
|
||||
#endif
|
||||
|
||||
#ifdef CONFIG_EARLY_PRINTK
|
||||
/* early_serial_console.c */
|
||||
extern int early_serial_base;
|
||||
void console_init(void);
|
||||
|
||||
#else
|
||||
|
||||
/* early_serial_console.c */
|
||||
static const int early_serial_base;
|
||||
static inline void console_init(void)
|
||||
{ }
|
||||
|
||||
#endif
|
||||
|
||||
#endif
|
||||
|
|
|
|||
|
|
@ -28,8 +28,6 @@
|
|||
#include <asm/required-features.h>
|
||||
#include <asm/msr-index.h>
|
||||
|
||||
struct cpu_features cpu;
|
||||
static u32 cpu_vendor[3];
|
||||
static u32 err_flags[NCAPINTS];
|
||||
|
||||
static const int req_level = CONFIG_X86_MINIMUM_CPU_FAMILY;
|
||||
|
|
@ -69,92 +67,8 @@ static int is_transmeta(void)
|
|||
cpu_vendor[2] == A32('M', 'x', '8', '6');
|
||||
}
|
||||
|
||||
static int has_fpu(void)
|
||||
{
|
||||
u16 fcw = -1, fsw = -1;
|
||||
u32 cr0;
|
||||
|
||||
asm("movl %%cr0,%0" : "=r" (cr0));
|
||||
if (cr0 & (X86_CR0_EM|X86_CR0_TS)) {
|
||||
cr0 &= ~(X86_CR0_EM|X86_CR0_TS);
|
||||
asm volatile("movl %0,%%cr0" : : "r" (cr0));
|
||||
}
|
||||
|
||||
asm volatile("fninit ; fnstsw %0 ; fnstcw %1"
|
||||
: "+m" (fsw), "+m" (fcw));
|
||||
|
||||
return fsw == 0 && (fcw & 0x103f) == 0x003f;
|
||||
}
|
||||
|
||||
static int has_eflag(u32 mask)
|
||||
{
|
||||
u32 f0, f1;
|
||||
|
||||
asm("pushfl ; "
|
||||
"pushfl ; "
|
||||
"popl %0 ; "
|
||||
"movl %0,%1 ; "
|
||||
"xorl %2,%1 ; "
|
||||
"pushl %1 ; "
|
||||
"popfl ; "
|
||||
"pushfl ; "
|
||||
"popl %1 ; "
|
||||
"popfl"
|
||||
: "=&r" (f0), "=&r" (f1)
|
||||
: "ri" (mask));
|
||||
|
||||
return !!((f0^f1) & mask);
|
||||
}
|
||||
|
||||
static void get_flags(void)
|
||||
{
|
||||
u32 max_intel_level, max_amd_level;
|
||||
u32 tfms;
|
||||
|
||||
if (has_fpu())
|
||||
set_bit(X86_FEATURE_FPU, cpu.flags);
|
||||
|
||||
if (has_eflag(X86_EFLAGS_ID)) {
|
||||
asm("cpuid"
|
||||
: "=a" (max_intel_level),
|
||||
"=b" (cpu_vendor[0]),
|
||||
"=d" (cpu_vendor[1]),
|
||||
"=c" (cpu_vendor[2])
|
||||
: "a" (0));
|
||||
|
||||
if (max_intel_level >= 0x00000001 &&
|
||||
max_intel_level <= 0x0000ffff) {
|
||||
asm("cpuid"
|
||||
: "=a" (tfms),
|
||||
"=c" (cpu.flags[4]),
|
||||
"=d" (cpu.flags[0])
|
||||
: "a" (0x00000001)
|
||||
: "ebx");
|
||||
cpu.level = (tfms >> 8) & 15;
|
||||
cpu.model = (tfms >> 4) & 15;
|
||||
if (cpu.level >= 6)
|
||||
cpu.model += ((tfms >> 16) & 0xf) << 4;
|
||||
}
|
||||
|
||||
asm("cpuid"
|
||||
: "=a" (max_amd_level)
|
||||
: "a" (0x80000000)
|
||||
: "ebx", "ecx", "edx");
|
||||
|
||||
if (max_amd_level >= 0x80000001 &&
|
||||
max_amd_level <= 0x8000ffff) {
|
||||
u32 eax = 0x80000001;
|
||||
asm("cpuid"
|
||||
: "+a" (eax),
|
||||
"=c" (cpu.flags[6]),
|
||||
"=d" (cpu.flags[1])
|
||||
: : "ebx");
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
/* Returns a bitmask of which words we have error bits in */
|
||||
static int check_flags(void)
|
||||
static int check_cpuflags(void)
|
||||
{
|
||||
u32 err;
|
||||
int i;
|
||||
|
|
@ -187,8 +101,8 @@ int check_cpu(int *cpu_level_ptr, int *req_level_ptr, u32 **err_flags_ptr)
|
|||
if (has_eflag(X86_EFLAGS_AC))
|
||||
cpu.level = 4;
|
||||
|
||||
get_flags();
|
||||
err = check_flags();
|
||||
get_cpuflags();
|
||||
err = check_cpuflags();
|
||||
|
||||
if (test_bit(X86_FEATURE_LM, cpu.flags))
|
||||
cpu.level = 64;
|
||||
|
|
@ -207,8 +121,8 @@ int check_cpu(int *cpu_level_ptr, int *req_level_ptr, u32 **err_flags_ptr)
|
|||
eax &= ~(1 << 15);
|
||||
asm("wrmsr" : : "a" (eax), "d" (edx), "c" (ecx));
|
||||
|
||||
get_flags(); /* Make sure it really did something */
|
||||
err = check_flags();
|
||||
get_cpuflags(); /* Make sure it really did something */
|
||||
err = check_cpuflags();
|
||||
} else if (err == 0x01 &&
|
||||
!(err_flags[0] & ~(1 << X86_FEATURE_CX8)) &&
|
||||
is_centaur() && cpu.model >= 6) {
|
||||
|
|
@ -223,7 +137,7 @@ int check_cpu(int *cpu_level_ptr, int *req_level_ptr, u32 **err_flags_ptr)
|
|||
asm("wrmsr" : : "a" (eax), "d" (edx), "c" (ecx));
|
||||
|
||||
set_bit(X86_FEATURE_CX8, cpu.flags);
|
||||
err = check_flags();
|
||||
err = check_cpuflags();
|
||||
} else if (err == 0x01 && is_transmeta()) {
|
||||
/* Transmeta might have masked feature bits in word 0 */
|
||||
|
||||
|
|
@ -238,7 +152,7 @@ int check_cpu(int *cpu_level_ptr, int *req_level_ptr, u32 **err_flags_ptr)
|
|||
: : "ecx", "ebx");
|
||||
asm("wrmsr" : : "a" (eax), "d" (edx), "c" (ecx));
|
||||
|
||||
err = check_flags();
|
||||
err = check_cpuflags();
|
||||
}
|
||||
|
||||
if (err_flags_ptr)
|
||||
|
|
|
|||
|
|
@ -0,0 +1,104 @@
|
|||
#include <linux/types.h>
|
||||
#include "bitops.h"
|
||||
|
||||
#include <asm/processor-flags.h>
|
||||
#include <asm/required-features.h>
|
||||
#include <asm/msr-index.h>
|
||||
#include "cpuflags.h"
|
||||
|
||||
struct cpu_features cpu;
|
||||
u32 cpu_vendor[3];
|
||||
|
||||
static bool loaded_flags;
|
||||
|
||||
static int has_fpu(void)
|
||||
{
|
||||
u16 fcw = -1, fsw = -1;
|
||||
unsigned long cr0;
|
||||
|
||||
asm volatile("mov %%cr0,%0" : "=r" (cr0));
|
||||
if (cr0 & (X86_CR0_EM|X86_CR0_TS)) {
|
||||
cr0 &= ~(X86_CR0_EM|X86_CR0_TS);
|
||||
asm volatile("mov %0,%%cr0" : : "r" (cr0));
|
||||
}
|
||||
|
||||
asm volatile("fninit ; fnstsw %0 ; fnstcw %1"
|
||||
: "+m" (fsw), "+m" (fcw));
|
||||
|
||||
return fsw == 0 && (fcw & 0x103f) == 0x003f;
|
||||
}
|
||||
|
||||
int has_eflag(unsigned long mask)
|
||||
{
|
||||
unsigned long f0, f1;
|
||||
|
||||
asm volatile("pushf \n\t"
|
||||
"pushf \n\t"
|
||||
"pop %0 \n\t"
|
||||
"mov %0,%1 \n\t"
|
||||
"xor %2,%1 \n\t"
|
||||
"push %1 \n\t"
|
||||
"popf \n\t"
|
||||
"pushf \n\t"
|
||||
"pop %1 \n\t"
|
||||
"popf"
|
||||
: "=&r" (f0), "=&r" (f1)
|
||||
: "ri" (mask));
|
||||
|
||||
return !!((f0^f1) & mask);
|
||||
}
|
||||
|
||||
/* Handle x86_32 PIC using ebx. */
|
||||
#if defined(__i386__) && defined(__PIC__)
|
||||
# define EBX_REG "=r"
|
||||
#else
|
||||
# define EBX_REG "=b"
|
||||
#endif
|
||||
|
||||
static inline void cpuid(u32 id, u32 *a, u32 *b, u32 *c, u32 *d)
|
||||
{
|
||||
asm volatile(".ifnc %%ebx,%3 ; movl %%ebx,%3 ; .endif \n\t"
|
||||
"cpuid \n\t"
|
||||
".ifnc %%ebx,%3 ; xchgl %%ebx,%3 ; .endif \n\t"
|
||||
: "=a" (*a), "=c" (*c), "=d" (*d), EBX_REG (*b)
|
||||
: "a" (id)
|
||||
);
|
||||
}
|
||||
|
||||
void get_cpuflags(void)
|
||||
{
|
||||
u32 max_intel_level, max_amd_level;
|
||||
u32 tfms;
|
||||
u32 ignored;
|
||||
|
||||
if (loaded_flags)
|
||||
return;
|
||||
loaded_flags = true;
|
||||
|
||||
if (has_fpu())
|
||||
set_bit(X86_FEATURE_FPU, cpu.flags);
|
||||
|
||||
if (has_eflag(X86_EFLAGS_ID)) {
|
||||
cpuid(0x0, &max_intel_level, &cpu_vendor[0], &cpu_vendor[2],
|
||||
&cpu_vendor[1]);
|
||||
|
||||
if (max_intel_level >= 0x00000001 &&
|
||||
max_intel_level <= 0x0000ffff) {
|
||||
cpuid(0x1, &tfms, &ignored, &cpu.flags[4],
|
||||
&cpu.flags[0]);
|
||||
cpu.level = (tfms >> 8) & 15;
|
||||
cpu.model = (tfms >> 4) & 15;
|
||||
if (cpu.level >= 6)
|
||||
cpu.model += ((tfms >> 16) & 0xf) << 4;
|
||||
}
|
||||
|
||||
cpuid(0x80000000, &max_amd_level, &ignored, &ignored,
|
||||
&ignored);
|
||||
|
||||
if (max_amd_level >= 0x80000001 &&
|
||||
max_amd_level <= 0x8000ffff) {
|
||||
cpuid(0x80000001, &ignored, &ignored, &cpu.flags[6],
|
||||
&cpu.flags[1]);
|
||||
}
|
||||
}
|
||||
}
|
||||
|
|
@ -0,0 +1,19 @@
|
|||
#ifndef BOOT_CPUFLAGS_H
|
||||
#define BOOT_CPUFLAGS_H
|
||||
|
||||
#include <asm/cpufeature.h>
|
||||
#include <asm/processor-flags.h>
|
||||
|
||||
struct cpu_features {
|
||||
int level; /* Family, or 64 for x86-64 */
|
||||
int model;
|
||||
u32 flags[NCAPINTS];
|
||||
};
|
||||
|
||||
extern struct cpu_features cpu;
|
||||
extern u32 cpu_vendor[3];
|
||||
|
||||
int has_eflag(unsigned long mask);
|
||||
void get_cpuflags(void);
|
||||
|
||||
#endif
|
||||
|
|
@ -39,6 +39,20 @@
|
|||
|
||||
#ifdef CONFIG_ARCH_RANDOM
|
||||
|
||||
/* Instead of arch_get_random_long() when alternatives haven't run. */
|
||||
static inline int rdrand_long(unsigned long *v)
|
||||
{
|
||||
int ok;
|
||||
asm volatile("1: " RDRAND_LONG "\n\t"
|
||||
"jc 2f\n\t"
|
||||
"decl %0\n\t"
|
||||
"jnz 1b\n\t"
|
||||
"2:"
|
||||
: "=r" (ok), "=a" (*v)
|
||||
: "0" (RDRAND_RETRY_LOOPS));
|
||||
return ok;
|
||||
}
|
||||
|
||||
#define GET_RANDOM(name, type, rdrand, nop) \
|
||||
static inline int name(type *v) \
|
||||
{ \
|
||||
|
|
@ -68,6 +82,13 @@ GET_RANDOM(arch_get_random_int, unsigned int, RDRAND_INT, ASM_NOP3);
|
|||
|
||||
#endif /* CONFIG_X86_64 */
|
||||
|
||||
#else
|
||||
|
||||
static inline int rdrand_long(unsigned long *v)
|
||||
{
|
||||
return 0;
|
||||
}
|
||||
|
||||
#endif /* CONFIG_ARCH_RANDOM */
|
||||
|
||||
extern void x86_init_rdrand(struct cpuinfo_x86 *c);
|
||||
|
|
|
|||
|
|
@ -39,9 +39,18 @@
|
|||
#define __VIRTUAL_MASK_SHIFT 47
|
||||
|
||||
/*
|
||||
* Kernel image size is limited to 512 MB (see level2_kernel_pgt in
|
||||
* arch/x86/kernel/head_64.S), and it is mapped here:
|
||||
* Kernel image size is limited to 1GiB due to the fixmap living in the
|
||||
* next 1GiB (see level2_kernel_pgt in arch/x86/kernel/head_64.S). Use
|
||||
* 512MiB by default, leaving 1.5GiB for modules once the page tables
|
||||
* are fully set up. If kernel ASLR is configured, it can extend the
|
||||
* kernel page table mapping, reducing the size of the modules area.
|
||||
*/
|
||||
#define KERNEL_IMAGE_SIZE (512 * 1024 * 1024)
|
||||
#define KERNEL_IMAGE_SIZE_DEFAULT (512 * 1024 * 1024)
|
||||
#if defined(CONFIG_RANDOMIZE_BASE) && \
|
||||
CONFIG_RANDOMIZE_BASE_MAX_OFFSET > KERNEL_IMAGE_SIZE_DEFAULT
|
||||
#define KERNEL_IMAGE_SIZE CONFIG_RANDOMIZE_BASE_MAX_OFFSET
|
||||
#else
|
||||
#define KERNEL_IMAGE_SIZE KERNEL_IMAGE_SIZE_DEFAULT
|
||||
#endif
|
||||
|
||||
#endif /* _ASM_X86_PAGE_64_DEFS_H */
|
||||
|
|
|
|||
|
|
@ -58,7 +58,7 @@ typedef struct { pteval_t pte; } pte_t;
|
|||
#define VMALLOC_START _AC(0xffffc90000000000, UL)
|
||||
#define VMALLOC_END _AC(0xffffe8ffffffffff, UL)
|
||||
#define VMEMMAP_START _AC(0xffffea0000000000, UL)
|
||||
#define MODULES_VADDR _AC(0xffffffffa0000000, UL)
|
||||
#define MODULES_VADDR (__START_KERNEL_map + KERNEL_IMAGE_SIZE)
|
||||
#define MODULES_END _AC(0xffffffffff000000, UL)
|
||||
#define MODULES_LEN (MODULES_END - MODULES_VADDR)
|
||||
|
||||
|
|
|
|||
|
|
@ -31,20 +31,6 @@ static int __init x86_rdrand_setup(char *s)
|
|||
}
|
||||
__setup("nordrand", x86_rdrand_setup);
|
||||
|
||||
/* We can't use arch_get_random_long() here since alternatives haven't run */
|
||||
static inline int rdrand_long(unsigned long *v)
|
||||
{
|
||||
int ok;
|
||||
asm volatile("1: " RDRAND_LONG "\n\t"
|
||||
"jc 2f\n\t"
|
||||
"decl %0\n\t"
|
||||
"jnz 1b\n\t"
|
||||
"2:"
|
||||
: "=r" (ok), "=a" (*v)
|
||||
: "0" (RDRAND_RETRY_LOOPS));
|
||||
return ok;
|
||||
}
|
||||
|
||||
/*
|
||||
* Force a reseed cycle; we are architecturally guaranteed a reseed
|
||||
* after no more than 512 128-bit chunks of random data. This also
|
||||
|
|
|
|||
|
|
@ -827,6 +827,20 @@ static void __init trim_low_memory_range(void)
|
|||
memblock_reserve(0, ALIGN(reserve_low, PAGE_SIZE));
|
||||
}
|
||||
|
||||
/*
|
||||
* Dump out kernel offset information on panic.
|
||||
*/
|
||||
static int
|
||||
dump_kernel_offset(struct notifier_block *self, unsigned long v, void *p)
|
||||
{
|
||||
pr_emerg("Kernel Offset: 0x%lx from 0x%lx "
|
||||
"(relocation range: 0x%lx-0x%lx)\n",
|
||||
(unsigned long)&_text - __START_KERNEL, __START_KERNEL,
|
||||
__START_KERNEL_map, MODULES_VADDR-1);
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
/*
|
||||
* Determine if we were loaded by an EFI loader. If so, then we have also been
|
||||
* passed the efi memmap, systab, etc., so we should use these data structures
|
||||
|
|
@ -1252,3 +1266,15 @@ void __init i386_reserve_resources(void)
|
|||
}
|
||||
|
||||
#endif /* CONFIG_X86_32 */
|
||||
|
||||
static struct notifier_block kernel_offset_notifier = {
|
||||
.notifier_call = dump_kernel_offset
|
||||
};
|
||||
|
||||
static int __init register_kernel_offset_dumper(void)
|
||||
{
|
||||
atomic_notifier_chain_register(&panic_notifier_list,
|
||||
&kernel_offset_notifier);
|
||||
return 0;
|
||||
}
|
||||
__initcall(register_kernel_offset_dumper);
|
||||
|
|
|
|||
|
|
@ -806,6 +806,9 @@ void __init mem_init(void)
|
|||
BUILD_BUG_ON(VMALLOC_START >= VMALLOC_END);
|
||||
#undef high_memory
|
||||
#undef __FIXADDR_TOP
|
||||
#ifdef CONFIG_RANDOMIZE_BASE
|
||||
BUILD_BUG_ON(CONFIG_RANDOMIZE_BASE_MAX_OFFSET > KERNEL_IMAGE_SIZE);
|
||||
#endif
|
||||
|
||||
#ifdef CONFIG_HIGHMEM
|
||||
BUG_ON(PKMAP_BASE + LAST_PKMAP*PAGE_SIZE > FIXADDR_START);
|
||||
|
|
|
|||
|
|
@ -722,15 +722,25 @@ static void percpu_init(void)
|
|||
|
||||
/*
|
||||
* Check to see if a symbol lies in the .data..percpu section.
|
||||
* For some as yet not understood reason the "__init_begin"
|
||||
* symbol which immediately preceeds the .data..percpu section
|
||||
* also shows up as it it were part of it so we do an explict
|
||||
* check for that symbol name and ignore it.
|
||||
*
|
||||
* The linker incorrectly associates some symbols with the
|
||||
* .data..percpu section so we also need to check the symbol
|
||||
* name to make sure that we classify the symbol correctly.
|
||||
*
|
||||
* The GNU linker incorrectly associates:
|
||||
* __init_begin
|
||||
* __per_cpu_load
|
||||
*
|
||||
* The "gold" linker incorrectly associates:
|
||||
* init_per_cpu__irq_stack_union
|
||||
* init_per_cpu__gdt_page
|
||||
*/
|
||||
static int is_percpu_sym(ElfW(Sym) *sym, const char *symname)
|
||||
{
|
||||
return (sym->st_shndx == per_cpu_shndx) &&
|
||||
strcmp(symname, "__init_begin");
|
||||
strcmp(symname, "__init_begin") &&
|
||||
strcmp(symname, "__per_cpu_load") &&
|
||||
strncmp(symname, "init_per_cpu_", 13);
|
||||
}
|
||||
|
||||
|
||||
|
|
|
|||
Loading…
Reference in New Issue