lkdtm: add "EXEC_*" triggers

Add new crash locations that attempt to execute non-executable memory
regions (data segment, stack, kmalloc, vmalloc).

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Kees Cook 2013-07-08 10:01:33 -07:00 committed by Greg Kroah-Hartman
parent 274a5855c0
commit cc33c537c1

View file

@ -43,6 +43,7 @@
#include <linux/slab.h>
#include <scsi/scsi_cmnd.h>
#include <linux/debugfs.h>
#include <linux/vmalloc.h>
#ifdef CONFIG_IDE
#include <linux/ide.h>
@ -50,6 +51,7 @@
#define DEFAULT_COUNT 10
#define REC_NUM_DEFAULT 10
#define EXEC_SIZE 64
enum cname {
CN_INVALID,
@ -80,6 +82,10 @@ enum ctype {
CT_HARDLOCKUP,
CT_SPINLOCKUP,
CT_HUNG_TASK,
CT_EXEC_DATA,
CT_EXEC_STACK,
CT_EXEC_KMALLOC,
CT_EXEC_VMALLOC,
};
static char* cp_name[] = {
@ -109,6 +115,10 @@ static char* cp_type[] = {
"HARDLOCKUP",
"SPINLOCKUP",
"HUNG_TASK",
"EXEC_DATA",
"EXEC_STACK",
"EXEC_KMALLOC",
"EXEC_VMALLOC",
};
static struct jprobe lkdtm;
@ -127,6 +137,8 @@ static int count = DEFAULT_COUNT;
static DEFINE_SPINLOCK(count_lock);
static DEFINE_SPINLOCK(lock_me_up);
static u8 data_area[EXEC_SIZE];
module_param(recur_count, int, 0644);
MODULE_PARM_DESC(recur_count, " Recursion level for the stack overflow test, "\
"default is 10");
@ -280,6 +292,19 @@ static int recursive_loop(int a)
return recursive_loop(a);
}
static void do_nothing(void)
{
return;
}
static void execute_location(void *dst)
{
void (*func)(void) = dst;
memcpy(dst, do_nothing, EXEC_SIZE);
func();
}
static void lkdtm_do_action(enum ctype which)
{
switch (which) {
@ -356,6 +381,26 @@ static void lkdtm_do_action(enum ctype which)
set_current_state(TASK_UNINTERRUPTIBLE);
schedule();
break;
case CT_EXEC_DATA:
execute_location(data_area);
break;
case CT_EXEC_STACK: {
u8 stack_area[EXEC_SIZE];
execute_location(stack_area);
break;
}
case CT_EXEC_KMALLOC: {
u32 *kmalloc_area = kmalloc(EXEC_SIZE, GFP_KERNEL);
execute_location(kmalloc_area);
kfree(kmalloc_area);
break;
}
case CT_EXEC_VMALLOC: {
u32 *vmalloc_area = vmalloc(EXEC_SIZE);
execute_location(vmalloc_area);
vfree(vmalloc_area);
break;
}
case CT_NONE:
default:
break;