Commit d29736d3 authored by Ye Bin's avatar Ye Bin Committed by Felix Fu
Browse files

arm32: kaslr: print kaslr offset when kernel panic 

hulk inclusion
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I8KNA9


CVE: NA

-------------------------------------------------

Signed-off-by: default avatarYe Bin <yebin10@huawei.com>
Signed-off-by: default avatarCui GaoSheng <cuigaosheng1@huawei.com>

Conflicts:
    Merge OLK-5.10 fix patch f59d4739

Signed-off-by: default avatarFelix Fu <fuzhen5@huawei.com>
parent 365a456a

arch/arm/include/asm/memory.h

+14 −0
Original line number Diff line number Diff line
@@ -171,6 +171,20 @@ extern unsigned long vectors_base; 
extern u64 kernel_sec_start;

extern u64 kernel_sec_end;



#ifdef CONFIG_RANDOMIZE_BASE

extern unsigned long __kaslr_offset;



static inline unsigned long kaslr_offset(void)

{

	return __kaslr_offset;

}

#else

static inline unsigned long kaslr_offset(void)

{

	return 0;

}

#endif



/*

 * Physical vs virtual RAM address space conversion.  These are

 * private definitions which should NOT be used outside memory.h

arch/arm/kernel/head.S

+3 −3
Original line number Diff line number Diff line
@@ -119,11 +119,11 @@ ENTRY(stext) 
#ifdef CONFIG_RANDOMIZE_BASE

	str_l	r3, __kaslr_offset, r9	@ offset in r3 if entered via kaslr ep



	.section ".bss", "aw", %nobits

	.pushsection .data		@ data in bss will be cleared

	.align	2

__kaslr_offset:

ENTRY(__kaslr_offset)

	.long	0			@ will be wiped before entering C code

	.previous

	.popsection

#endif



#ifdef CONFIG_ARM_VIRT_EXT

arch/arm/kernel/setup.c

+31 −0
Original line number Diff line number Diff line
@@ -60,6 +60,7 @@ 
#include <asm/memblock.h>

#include <asm/virt.h>

#include <asm/kasan.h>

#include <linux/panic_notifier.h>



#include "atags.h"
@@ -1359,3 +1360,33 @@ const struct seq_operations cpuinfo_op = { 
	.stop	= c_stop,

	.show	= c_show

};



/*

 * Dump out kernel offset information on panic.

 */

static int dump_kernel_offset(struct notifier_block *self, unsigned long v,

			      void *p)

{

	const unsigned long offset = kaslr_offset();



	if (IS_ENABLED(CONFIG_RANDOMIZE_BASE) && offset > 0) {

		pr_emerg("Kernel Offset: 0x%lx from 0x%lx\n",

			 offset, PAGE_OFFSET);



	} else {

		pr_emerg("Kernel Offset: disabled\n");

	}

	return 0;

}



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);