New tests for prior memory protections (EXEC_RODATA), new tests for upcoming
kernel self-protections (USERCOPY_HEAP_SIZE_TO, USERCOPY_HEAP_SIZE_FROM, USERCOPY_HEAP_FLAG_TO, USERCOPY_HEAP_FLAG_FROM, USERCOPY_STACK_FRAME_TO, USERCOPY_STACK_FRAME_FROM, USERCOPY_STACK_BEYOND), and updated tests (ATOMIC_UNDERFLOW, ATOMIC_OVERFLOW). -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 Comment: Kees Cook <kees@outflux.net> iQIcBAABCgAGBQJXW0bEAAoJEIly9N/cbcAmgiwP/2/vQMRJ087Mbf6EUewaA5Aw URwAhaXYtLH8wSTclQ9S1VNxWkpZHqCKyM0WnZ9S1LN1JhK8Nh1fDp1efsDOLJ2H f8I0Pbycpk5MnTqzuMdbH71bvNeAnCAkCsOyT+CHyy9fNfwMd8hlbWGPX1Pozz4b j5qBMHI8TCRMU6p6BbwEBo6gEPmPiMgfOTaMBFgijvI9RtBd0DJLwDpkn0pxwM74 m1T0AiBpZ2trKG0LeGVkcW/UvFJ8cD7i/ytSK3tel9ghKMPGzQNG16XPumGyXhZ3 r5Z+6Hj8H9UGBJNVmFOgG+Dxw3BQeZJyrKCGtadCC8Ml3qryQ1CZ/knGfpMMl3e5 ynmKXMLpsu6yD/Fnp7CVDR7yI2zaqpG7IunZgP8jVAk6FxgqV7Mei31G0L9sgQ+I pJlX58VRl/8wLeDuBpqJ3JOQrKUGWJV0+h08SDauY5pqdrMUtCQgOrJR7wHBUx/f ci/JqnfT98GAmZYsjW46y6KsK3x5nNHFYKhSKvytIONZNsv8RMnvwbNsC65q9W7D R6zwyPNNhgFEuiNNVW7Iy7eQsM4Fk0gp2Pd0pdB5nXMd3yl7AAXv2S1C0SFTuZ19 nGvB4K6yQNvM9Uba0bLfCHgVto/vTOySPdFPQ2WaaPkSlaYx+ZvD16LA1s+UawQm Z4yW5oDQPLVC2PY5XvQc =LUgp -----END PGP SIGNATURE----- Merge tag 'lkdtm-next' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux into char-misc-testing Kees writes: New tests for prior memory protections (EXEC_RODATA), new tests for upcoming kernel self-protections (USERCOPY_HEAP_SIZE_TO, USERCOPY_HEAP_SIZE_FROM, USERCOPY_HEAP_FLAG_TO, USERCOPY_HEAP_FLAG_FROM, USERCOPY_STACK_FRAME_TO, USERCOPY_STACK_FRAME_FROM, USERCOPY_STACK_BEYOND), and updated tests (ATOMIC_UNDERFLOW, ATOMIC_OVERFLOW).
This commit is contained in:
Greg Kroah-Hartman
commit
dc1392727e
5 changed files with 341 additions and 20 deletions
|
|
@ -6954,7 +6954,7 @@ T: git git://git.kernel.org/pub/scm/linux/kernel/git/jikos/livepatching.git
|
|||
LINUX KERNEL DUMP TEST MODULE (LKDTM)
|
||||
M: Kees Cook <keescook@chromium.org>
|
||||
S: Maintained
|
||||
F: drivers/misc/lkdtm.c
|
||||
F: drivers/misc/lkdtm*
|
||||
|
||||
LLC (802.2)
|
||||
M: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
|
||||
|
|
|
|||
|
|
@ -57,3 +57,13 @@ obj-$(CONFIG_ECHO) += echo/
|
|||
obj-$(CONFIG_VEXPRESS_SYSCFG) += vexpress-syscfg.o
|
||||
obj-$(CONFIG_CXL_BASE) += cxl/
|
||||
obj-$(CONFIG_PANEL) += panel.o
|
||||
|
||||
lkdtm-$(CONFIG_LKDTM) += lkdtm_core.o
|
||||
lkdtm-$(CONFIG_LKDTM) += lkdtm_rodata_objcopy.o
|
||||
|
||||
OBJCOPYFLAGS :=
|
||||
OBJCOPYFLAGS_lkdtm_rodata_objcopy.o := \
|
||||
--set-section-flags .text=alloc,readonly \
|
||||
--rename-section .text=.rodata
|
||||
$(obj)/lkdtm_rodata_objcopy.o: $(obj)/lkdtm_rodata.o
|
||||
$(call if_changed,objcopy)
|
||||
|
|
|
|||
6
drivers/misc/lkdtm.h
Normal file
6
drivers/misc/lkdtm.h
Normal file
|
|
@ -0,0 +1,6 @@
|
|||
#ifndef __LKDTM_H
|
||||
#define __LKDTM_H
|
||||
|
||||
void lkdtm_rodata_do_nothing(void);
|
||||
|
||||
#endif
|
||||
|
|
@ -1,5 +1,9 @@
|
|||
/*
|
||||
* Kprobe module for testing crash dumps
|
||||
* Linux Kernel Dump Test Module for testing kernel crashes conditions:
|
||||
* induces system failures at predefined crashpoints and under predefined
|
||||
* operational conditions in order to evaluate the reliability of kernel
|
||||
* sanity checking and crash dumps obtained using different dumping
|
||||
* solutions.
|
||||
*
|
||||
* This program is free software; you can redistribute it and/or modify
|
||||
* it under the terms of the GNU General Public License as published by
|
||||
|
|
@ -19,10 +23,6 @@
|
|||
*
|
||||
* Author: Ankita Garg <ankita@in.ibm.com>
|
||||
*
|
||||
* This module induces system failures at predefined crashpoints to
|
||||
* evaluate the reliability of crash dumps obtained using different dumping
|
||||
* solutions.
|
||||
*
|
||||
* It is adapted from the Linux Kernel Dump Test Tool by
|
||||
* Fernando Luis Vazquez Cao <http://lkdtt.sourceforge.net>
|
||||
*
|
||||
|
|
@ -30,7 +30,7 @@
|
|||
*
|
||||
* See Documentation/fault-injection/provoke-crashes.txt for instructions
|
||||
*/
|
||||
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
|
||||
#define pr_fmt(fmt) "lkdtm: " fmt
|
||||
|
||||
#include <linux/kernel.h>
|
||||
#include <linux/fs.h>
|
||||
|
|
@ -52,6 +52,8 @@
|
|||
#include <linux/ide.h>
|
||||
#endif
|
||||
|
||||
#include "lkdtm.h"
|
||||
|
||||
/*
|
||||
* Make sure our attempts to over run the kernel stack doesn't trigger
|
||||
* a compiler warning when CONFIG_FRAME_WARN is set. Then make sure we
|
||||
|
|
@ -103,12 +105,21 @@ enum ctype {
|
|||
CT_EXEC_STACK,
|
||||
CT_EXEC_KMALLOC,
|
||||
CT_EXEC_VMALLOC,
|
||||
CT_EXEC_RODATA,
|
||||
CT_EXEC_USERSPACE,
|
||||
CT_ACCESS_USERSPACE,
|
||||
CT_WRITE_RO,
|
||||
CT_WRITE_RO_AFTER_INIT,
|
||||
CT_WRITE_KERN,
|
||||
CT_WRAP_ATOMIC
|
||||
CT_ATOMIC_UNDERFLOW,
|
||||
CT_ATOMIC_OVERFLOW,
|
||||
CT_USERCOPY_HEAP_SIZE_TO,
|
||||
CT_USERCOPY_HEAP_SIZE_FROM,
|
||||
CT_USERCOPY_HEAP_FLAG_TO,
|
||||
CT_USERCOPY_HEAP_FLAG_FROM,
|
||||
CT_USERCOPY_STACK_FRAME_TO,
|
||||
CT_USERCOPY_STACK_FRAME_FROM,
|
||||
CT_USERCOPY_STACK_BEYOND,
|
||||
};
|
||||
|
||||
static char* cp_name[] = {
|
||||
|
|
@ -145,12 +156,21 @@ static char* cp_type[] = {
|
|||
"EXEC_STACK",
|
||||
"EXEC_KMALLOC",
|
||||
"EXEC_VMALLOC",
|
||||
"EXEC_RODATA",
|
||||
"EXEC_USERSPACE",
|
||||
"ACCESS_USERSPACE",
|
||||
"WRITE_RO",
|
||||
"WRITE_RO_AFTER_INIT",
|
||||
"WRITE_KERN",
|
||||
"WRAP_ATOMIC"
|
||||
"ATOMIC_UNDERFLOW",
|
||||
"ATOMIC_OVERFLOW",
|
||||
"USERCOPY_HEAP_SIZE_TO",
|
||||
"USERCOPY_HEAP_SIZE_FROM",
|
||||
"USERCOPY_HEAP_FLAG_TO",
|
||||
"USERCOPY_HEAP_FLAG_FROM",
|
||||
"USERCOPY_STACK_FRAME_TO",
|
||||
"USERCOPY_STACK_FRAME_FROM",
|
||||
"USERCOPY_STACK_BEYOND",
|
||||
};
|
||||
|
||||
static struct jprobe lkdtm;
|
||||
|
|
@ -162,6 +182,8 @@ static char* cpoint_name;
|
|||
static char* cpoint_type;
|
||||
static int cpoint_count = DEFAULT_COUNT;
|
||||
static int recur_count = REC_NUM_DEFAULT;
|
||||
static int alloc_size = 1024;
|
||||
static size_t cache_size;
|
||||
|
||||
static enum cname cpoint = CN_INVALID;
|
||||
static enum ctype cptype = CT_NONE;
|
||||
|
|
@ -170,7 +192,9 @@ static DEFINE_SPINLOCK(count_lock);
|
|||
static DEFINE_SPINLOCK(lock_me_up);
|
||||
|
||||
static u8 data_area[EXEC_SIZE];
|
||||
static struct kmem_cache *bad_cache;
|
||||
|
||||
static const unsigned char test_text[] = "This is a test.\n";
|
||||
static const unsigned long rodata = 0xAA55AA55;
|
||||
static unsigned long ro_after_init __ro_after_init = 0x55AA5500;
|
||||
|
||||
|
|
@ -184,6 +208,9 @@ MODULE_PARM_DESC(cpoint_type, " Crash Point Type, action to be taken on "\
|
|||
module_param(cpoint_count, int, 0644);
|
||||
MODULE_PARM_DESC(cpoint_count, " Crash Point Count, number of times the "\
|
||||
"crash point is to be hit to trigger action");
|
||||
module_param(alloc_size, int, 0644);
|
||||
MODULE_PARM_DESC(alloc_size, " Size of allocation for user copy tests "\
|
||||
"(from 1 to PAGE_SIZE)");
|
||||
|
||||
static unsigned int jp_do_irq(unsigned int irq)
|
||||
{
|
||||
|
|
@ -346,15 +373,18 @@ static noinline void corrupt_stack(void)
|
|||
memset((void *)data, 0, 64);
|
||||
}
|
||||
|
||||
static void noinline execute_location(void *dst)
|
||||
static noinline void execute_location(void *dst, bool write)
|
||||
{
|
||||
void (*func)(void) = dst;
|
||||
|
||||
pr_info("attempting ok execution at %p\n", do_nothing);
|
||||
do_nothing();
|
||||
|
||||
memcpy(dst, do_nothing, EXEC_SIZE);
|
||||
flush_icache_range((unsigned long)dst, (unsigned long)dst + EXEC_SIZE);
|
||||
if (write) {
|
||||
memcpy(dst, do_nothing, EXEC_SIZE);
|
||||
flush_icache_range((unsigned long)dst,
|
||||
(unsigned long)dst + EXEC_SIZE);
|
||||
}
|
||||
pr_info("attempting bad execution at %p\n", func);
|
||||
func();
|
||||
}
|
||||
|
|
@ -374,6 +404,228 @@ static void execute_user_location(void *dst)
|
|||
func();
|
||||
}
|
||||
|
||||
/*
|
||||
* Instead of adding -Wno-return-local-addr, just pass the stack address
|
||||
* through a function to obfuscate it from the compiler.
|
||||
*/
|
||||
static noinline unsigned char *trick_compiler(unsigned char *stack)
|
||||
{
|
||||
return stack + 0;
|
||||
}
|
||||
|
||||
static noinline unsigned char *do_usercopy_stack_callee(int value)
|
||||
{
|
||||
unsigned char buf[32];
|
||||
int i;
|
||||
|
||||
/* Exercise stack to avoid everything living in registers. */
|
||||
for (i = 0; i < sizeof(buf); i++) {
|
||||
buf[i] = value & 0xff;
|
||||
}
|
||||
|
||||
return trick_compiler(buf);
|
||||
}
|
||||
|
||||
static noinline void do_usercopy_stack(bool to_user, bool bad_frame)
|
||||
{
|
||||
unsigned long user_addr;
|
||||
unsigned char good_stack[32];
|
||||
unsigned char *bad_stack;
|
||||
int i;
|
||||
|
||||
/* Exercise stack to avoid everything living in registers. */
|
||||
for (i = 0; i < sizeof(good_stack); i++)
|
||||
good_stack[i] = test_text[i % sizeof(test_text)];
|
||||
|
||||
/* This is a pointer to outside our current stack frame. */
|
||||
if (bad_frame) {
|
||||
bad_stack = do_usercopy_stack_callee(alloc_size);
|
||||
} else {
|
||||
/* Put start address just inside stack. */
|
||||
bad_stack = task_stack_page(current) + THREAD_SIZE;
|
||||
bad_stack -= sizeof(unsigned long);
|
||||
}
|
||||
|
||||
user_addr = vm_mmap(NULL, 0, PAGE_SIZE,
|
||||
PROT_READ | PROT_WRITE | PROT_EXEC,
|
||||
MAP_ANONYMOUS | MAP_PRIVATE, 0);
|
||||
if (user_addr >= TASK_SIZE) {
|
||||
pr_warn("Failed to allocate user memory\n");
|
||||
return;
|
||||
}
|
||||
|
||||
if (to_user) {
|
||||
pr_info("attempting good copy_to_user of local stack\n");
|
||||
if (copy_to_user((void __user *)user_addr, good_stack,
|
||||
sizeof(good_stack))) {
|
||||
pr_warn("copy_to_user failed unexpectedly?!\n");
|
||||
goto free_user;
|
||||
}
|
||||
|
||||
pr_info("attempting bad copy_to_user of distant stack\n");
|
||||
if (copy_to_user((void __user *)user_addr, bad_stack,
|
||||
sizeof(good_stack))) {
|
||||
pr_warn("copy_to_user failed, but lacked Oops\n");
|
||||
goto free_user;
|
||||
}
|
||||
} else {
|
||||
/*
|
||||
* There isn't a safe way to not be protected by usercopy
|
||||
* if we're going to write to another thread's stack.
|
||||
*/
|
||||
if (!bad_frame)
|
||||
goto free_user;
|
||||
|
||||
pr_info("attempting good copy_from_user of local stack\n");
|
||||
if (copy_from_user(good_stack, (void __user *)user_addr,
|
||||
sizeof(good_stack))) {
|
||||
pr_warn("copy_from_user failed unexpectedly?!\n");
|
||||
goto free_user;
|
||||
}
|
||||
|
||||
pr_info("attempting bad copy_from_user of distant stack\n");
|
||||
if (copy_from_user(bad_stack, (void __user *)user_addr,
|
||||
sizeof(good_stack))) {
|
||||
pr_warn("copy_from_user failed, but lacked Oops\n");
|
||||
goto free_user;
|
||||
}
|
||||
}
|
||||
|
||||
free_user:
|
||||
vm_munmap(user_addr, PAGE_SIZE);
|
||||
}
|
||||
|
||||
static void do_usercopy_heap_size(bool to_user)
|
||||
{
|
||||
unsigned long user_addr;
|
||||
unsigned char *one, *two;
|
||||
size_t size = clamp_t(int, alloc_size, 1, PAGE_SIZE);
|
||||
|
||||
one = kmalloc(size, GFP_KERNEL);
|
||||
two = kmalloc(size, GFP_KERNEL);
|
||||
if (!one || !two) {
|
||||
pr_warn("Failed to allocate kernel memory\n");
|
||||
goto free_kernel;
|
||||
}
|
||||
|
||||
user_addr = vm_mmap(NULL, 0, PAGE_SIZE,
|
||||
PROT_READ | PROT_WRITE | PROT_EXEC,
|
||||
MAP_ANONYMOUS | MAP_PRIVATE, 0);
|
||||
if (user_addr >= TASK_SIZE) {
|
||||
pr_warn("Failed to allocate user memory\n");
|
||||
goto free_kernel;
|
||||
}
|
||||
|
||||
memset(one, 'A', size);
|
||||
memset(two, 'B', size);
|
||||
|
||||
if (to_user) {
|
||||
pr_info("attempting good copy_to_user of correct size\n");
|
||||
if (copy_to_user((void __user *)user_addr, one, size)) {
|
||||
pr_warn("copy_to_user failed unexpectedly?!\n");
|
||||
goto free_user;
|
||||
}
|
||||
|
||||
pr_info("attempting bad copy_to_user of too large size\n");
|
||||
if (copy_to_user((void __user *)user_addr, one, 2 * size)) {
|
||||
pr_warn("copy_to_user failed, but lacked Oops\n");
|
||||
goto free_user;
|
||||
}
|
||||
} else {
|
||||
pr_info("attempting good copy_from_user of correct size\n");
|
||||
if (copy_from_user(one, (void __user *)user_addr,
|
||||
size)) {
|
||||
pr_warn("copy_from_user failed unexpectedly?!\n");
|
||||
goto free_user;
|
||||
}
|
||||
|
||||
pr_info("attempting bad copy_from_user of too large size\n");
|
||||
if (copy_from_user(one, (void __user *)user_addr, 2 * size)) {
|
||||
pr_warn("copy_from_user failed, but lacked Oops\n");
|
||||
goto free_user;
|
||||
}
|
||||
}
|
||||
|
||||
free_user:
|
||||
vm_munmap(user_addr, PAGE_SIZE);
|
||||
free_kernel:
|
||||
kfree(one);
|
||||
kfree(two);
|
||||
}
|
||||
|
||||
static void do_usercopy_heap_flag(bool to_user)
|
||||
{
|
||||
unsigned long user_addr;
|
||||
unsigned char *good_buf = NULL;
|
||||
unsigned char *bad_buf = NULL;
|
||||
|
||||
/* Make sure cache was prepared. */
|
||||
if (!bad_cache) {
|
||||
pr_warn("Failed to allocate kernel cache\n");
|
||||
return;
|
||||
}
|
||||
|
||||
/*
|
||||
* Allocate one buffer from each cache (kmalloc will have the
|
||||
* SLAB_USERCOPY flag already, but "bad_cache" won't).
|
||||
*/
|
||||
good_buf = kmalloc(cache_size, GFP_KERNEL);
|
||||
bad_buf = kmem_cache_alloc(bad_cache, GFP_KERNEL);
|
||||
if (!good_buf || !bad_buf) {
|
||||
pr_warn("Failed to allocate buffers from caches\n");
|
||||
goto free_alloc;
|
||||
}
|
||||
|
||||
/* Allocate user memory we'll poke at. */
|
||||
user_addr = vm_mmap(NULL, 0, PAGE_SIZE,
|
||||
PROT_READ | PROT_WRITE | PROT_EXEC,
|
||||
MAP_ANONYMOUS | MAP_PRIVATE, 0);
|
||||
if (user_addr >= TASK_SIZE) {
|
||||
pr_warn("Failed to allocate user memory\n");
|
||||
goto free_alloc;
|
||||
}
|
||||
|
||||
memset(good_buf, 'A', cache_size);
|
||||
memset(bad_buf, 'B', cache_size);
|
||||
|
||||
if (to_user) {
|
||||
pr_info("attempting good copy_to_user with SLAB_USERCOPY\n");
|
||||
if (copy_to_user((void __user *)user_addr, good_buf,
|
||||
cache_size)) {
|
||||
pr_warn("copy_to_user failed unexpectedly?!\n");
|
||||
goto free_user;
|
||||
}
|
||||
|
||||
pr_info("attempting bad copy_to_user w/o SLAB_USERCOPY\n");
|
||||
if (copy_to_user((void __user *)user_addr, bad_buf,
|
||||
cache_size)) {
|
||||
pr_warn("copy_to_user failed, but lacked Oops\n");
|
||||
goto free_user;
|
||||
}
|
||||
} else {
|
||||
pr_info("attempting good copy_from_user with SLAB_USERCOPY\n");
|
||||
if (copy_from_user(good_buf, (void __user *)user_addr,
|
||||
cache_size)) {
|
||||
pr_warn("copy_from_user failed unexpectedly?!\n");
|
||||
goto free_user;
|
||||
}
|
||||
|
||||
pr_info("attempting bad copy_from_user w/o SLAB_USERCOPY\n");
|
||||
if (copy_from_user(bad_buf, (void __user *)user_addr,
|
||||
cache_size)) {
|
||||
pr_warn("copy_from_user failed, but lacked Oops\n");
|
||||
goto free_user;
|
||||
}
|
||||
}
|
||||
|
||||
free_user:
|
||||
vm_munmap(user_addr, PAGE_SIZE);
|
||||
free_alloc:
|
||||
if (bad_buf)
|
||||
kmem_cache_free(bad_cache, bad_buf);
|
||||
kfree(good_buf);
|
||||
}
|
||||
|
||||
static void lkdtm_do_action(enum ctype which)
|
||||
{
|
||||
switch (which) {
|
||||
|
|
@ -551,25 +803,28 @@ static void lkdtm_do_action(enum ctype which)
|
|||
schedule();
|
||||
break;
|
||||
case CT_EXEC_DATA:
|
||||
execute_location(data_area);
|
||||
execute_location(data_area, true);
|
||||
break;
|
||||
case CT_EXEC_STACK: {
|
||||
u8 stack_area[EXEC_SIZE];
|
||||
execute_location(stack_area);
|
||||
execute_location(stack_area, true);
|
||||
break;
|
||||
}
|
||||
case CT_EXEC_KMALLOC: {
|
||||
u32 *kmalloc_area = kmalloc(EXEC_SIZE, GFP_KERNEL);
|
||||
execute_location(kmalloc_area);
|
||||
execute_location(kmalloc_area, true);
|
||||
kfree(kmalloc_area);
|
||||
break;
|
||||
}
|
||||
case CT_EXEC_VMALLOC: {
|
||||
u32 *vmalloc_area = vmalloc(EXEC_SIZE);
|
||||
execute_location(vmalloc_area);
|
||||
execute_location(vmalloc_area, true);
|
||||
vfree(vmalloc_area);
|
||||
break;
|
||||
}
|
||||
case CT_EXEC_RODATA:
|
||||
execute_location(lkdtm_rodata_do_nothing, false);
|
||||
break;
|
||||
case CT_EXEC_USERSPACE: {
|
||||
unsigned long user_addr;
|
||||
|
||||
|
|
@ -658,17 +913,50 @@ static void lkdtm_do_action(enum ctype which)
|
|||
do_overwritten();
|
||||
break;
|
||||
}
|
||||
case CT_WRAP_ATOMIC: {
|
||||
case CT_ATOMIC_UNDERFLOW: {
|
||||
atomic_t under = ATOMIC_INIT(INT_MIN);
|
||||
|
||||
pr_info("attempting good atomic increment\n");
|
||||
atomic_inc(&under);
|
||||
atomic_dec(&under);
|
||||
|
||||
pr_info("attempting bad atomic underflow\n");
|
||||
atomic_dec(&under);
|
||||
break;
|
||||
}
|
||||
case CT_ATOMIC_OVERFLOW: {
|
||||
atomic_t over = ATOMIC_INIT(INT_MAX);
|
||||
|
||||
pr_info("attempting atomic underflow\n");
|
||||
atomic_dec(&under);
|
||||
pr_info("attempting atomic overflow\n");
|
||||
pr_info("attempting good atomic decrement\n");
|
||||
atomic_dec(&over);
|
||||
atomic_inc(&over);
|
||||
|
||||
pr_info("attempting bad atomic overflow\n");
|
||||
atomic_inc(&over);
|
||||
|
||||
return;
|
||||
}
|
||||
case CT_USERCOPY_HEAP_SIZE_TO:
|
||||
do_usercopy_heap_size(true);
|
||||
break;
|
||||
case CT_USERCOPY_HEAP_SIZE_FROM:
|
||||
do_usercopy_heap_size(false);
|
||||
break;
|
||||
case CT_USERCOPY_HEAP_FLAG_TO:
|
||||
do_usercopy_heap_flag(true);
|
||||
break;
|
||||
case CT_USERCOPY_HEAP_FLAG_FROM:
|
||||
do_usercopy_heap_flag(false);
|
||||
break;
|
||||
case CT_USERCOPY_STACK_FRAME_TO:
|
||||
do_usercopy_stack(true, true);
|
||||
break;
|
||||
case CT_USERCOPY_STACK_FRAME_FROM:
|
||||
do_usercopy_stack(false, true);
|
||||
break;
|
||||
case CT_USERCOPY_STACK_BEYOND:
|
||||
do_usercopy_stack(true, false);
|
||||
break;
|
||||
case CT_NONE:
|
||||
default:
|
||||
break;
|
||||
|
|
@ -961,6 +1249,11 @@ static int __init lkdtm_module_init(void)
|
|||
/* Make sure we can write to __ro_after_init values during __init */
|
||||
ro_after_init |= 0xAA;
|
||||
|
||||
/* Prepare cache that lacks SLAB_USERCOPY flag. */
|
||||
cache_size = clamp_t(int, alloc_size, 1, PAGE_SIZE);
|
||||
bad_cache = kmem_cache_create("lkdtm-no-usercopy", cache_size, 0,
|
||||
0, NULL);
|
||||
|
||||
/* Register debugfs interface */
|
||||
lkdtm_debugfs_root = debugfs_create_dir("provoke-crash", NULL);
|
||||
if (!lkdtm_debugfs_root) {
|
||||
|
|
@ -1012,6 +1305,8 @@ static void __exit lkdtm_module_exit(void)
|
|||
{
|
||||
debugfs_remove_recursive(lkdtm_debugfs_root);
|
||||
|
||||
kmem_cache_destroy(bad_cache);
|
||||
|
||||
unregister_jprobe(&lkdtm);
|
||||
pr_info("Crash point unregistered\n");
|
||||
}
|
||||
10
drivers/misc/lkdtm_rodata.c
Normal file
10
drivers/misc/lkdtm_rodata.c
Normal file
|
|
@ -0,0 +1,10 @@
|
|||
/*
|
||||
* This includes functions that are meant to live entirely in .rodata
|
||||
* (via objcopy tricks), to validate the non-executability of .rodata.
|
||||
*/
|
||||
#include <linux/kernel.h>
|
||||
|
||||
void lkdtm_rodata_do_nothing(void)
|
||||
{
|
||||
/* Does nothing. We just want an architecture agnostic "return". */
|
||||
}
|
||||
Loading…
Reference in a new issue