You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
kernel_samsung_sm7125/arch/x86/lib/kaslr.c

91 lines
2.1 KiB

x86/mm: Refactor KASLR entropy functions Move the KASLR entropy functions into arch/x86/lib to be used in early kernel boot for KASLR memory randomization. Signed-off-by: Thomas Garnier <thgarnie@google.com> Signed-off-by: Kees Cook <keescook@chromium.org> Cc: Alexander Kuleshov <kuleshovmail@gmail.com> Cc: Alexander Popov <alpopov@ptsecurity.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Cc: Baoquan He <bhe@redhat.com> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Borislav Petkov <bp@suse.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Dave Young <dyoung@redhat.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Jan Beulich <JBeulich@suse.com> Cc: Joerg Roedel <jroedel@suse.de> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Juergen Gross <jgross@suse.com> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Lv Zheng <lv.zheng@intel.com> Cc: Mark Salter <msalter@redhat.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Matt Fleming <matt@codeblueprint.co.uk> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephen Smalley <sds@tycho.nsa.gov> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Toshi Kani <toshi.kani@hpe.com> Cc: Xiao Guangrong <guangrong.xiao@linux.intel.com> Cc: Yinghai Lu <yinghai@kernel.org> Cc: kernel-hardening@lists.openwall.com Cc: linux-doc@vger.kernel.org Link: http://lkml.kernel.org/r/1466556426-32664-2-git-send-email-keescook@chromium.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
9 years ago
/*
* 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/kaslr.h>
#include <asm/msr.h>
#include <asm/archrandom.h>
#include <asm/e820.h>
#include <asm/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)
x86/mm: Refactor KASLR entropy functions Move the KASLR entropy functions into arch/x86/lib to be used in early kernel boot for KASLR memory randomization. Signed-off-by: Thomas Garnier <thgarnie@google.com> Signed-off-by: Kees Cook <keescook@chromium.org> Cc: Alexander Kuleshov <kuleshovmail@gmail.com> Cc: Alexander Popov <alpopov@ptsecurity.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Cc: Baoquan He <bhe@redhat.com> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Borislav Petkov <bp@suse.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Dave Young <dyoung@redhat.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Jan Beulich <JBeulich@suse.com> Cc: Joerg Roedel <jroedel@suse.de> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Juergen Gross <jgross@suse.com> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Lv Zheng <lv.zheng@intel.com> Cc: Mark Salter <msalter@redhat.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Matt Fleming <matt@codeblueprint.co.uk> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephen Smalley <sds@tycho.nsa.gov> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Toshi Kani <toshi.kani@hpe.com> Cc: Xiao Guangrong <guangrong.xiao@linux.intel.com> Cc: Yinghai Lu <yinghai@kernel.org> Cc: kernel-hardening@lists.openwall.com Cc: linux-doc@vger.kernel.org Link: http://lkml.kernel.org/r/1466556426-32664-2-git-send-email-keescook@chromium.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
9 years ago
#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_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);
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;
debug_putstr(purpose);
debug_putstr(" KASLR using");
if (has_cpuflag(X86_FEATURE_RDRAND)) {
debug_putstr(" RDRAND");
if (rdrand_long(&raw)) {
random ^= raw;
use_i8254 = false;
}
}
if (has_cpuflag(X86_FEATURE_TSC)) {
debug_putstr(" RDTSC");
raw = rdtsc();
random ^= raw;
use_i8254 = false;
}
if (use_i8254) {
debug_putstr(" i8254");
random ^= i8254();
}
/* Circular multiply for better bit diffusion */
asm("mul %3"
: "=a" (random), "=d" (raw)
: "a" (random), "rm" (mix_const));
random += raw;
debug_putstr("...\n");
return random;
}