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//#include <cutils/misc.h>
#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sched.h>
#include <errno.h>
#include <signal.h>
#include <sys/ptrace.h>
#include <sys/wait.h>
#include <sys/socket.h>
#include <pthread.h>
#include <cutils/sockets.h>
extern const char* __progname;
void crash1(void);
void crashnostack(void);
static int do_action(const char* arg);
static void maybeabort() {
if(time(0) != 42) {
abort();
}
}
static int smash_stack(int i) {
printf("crasher: deliberately corrupting stack...\n");
// Unless there's a "big enough" buffer on the stack, gcc
// doesn't bother inserting checks.
char buf[8];
// If we don't write something relatively unpredictable
// into the buffer and then do something with it, gcc
// optimizes everything away and just returns a constant.
*(int*)(&buf[7]) = (uintptr_t) &buf[0];
return *(int*)(&buf[0]);
}
static void* global = 0; // So GCC doesn't optimize the tail recursion out of overflow_stack.
__attribute__((noinline)) static void overflow_stack(void* p) {
void* buf[1];
buf[0] = p;
global = buf;
overflow_stack(&buf);
}
static void test_call1()
{
*((int*) 32) = 1;
}
static void *noisy(void *x)
{
char c = (uintptr_t) x;
for(;;) {
usleep(250*1000);
write(2, &c, 1);
if(c == 'C') *((unsigned*) 0) = 42;
}
return NULL;
}
static int ctest()
{
pthread_t thr;
pthread_attr_t attr;
pthread_attr_init(&attr);
pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
pthread_create(&thr, &attr, noisy, (void*) 'A');
pthread_create(&thr, &attr, noisy, (void*) 'B');
pthread_create(&thr, &attr, noisy, (void*) 'C');
for(;;) ;
return 0;
}
static void* thread_callback(void* raw_arg)
{
return (void*) (uintptr_t) do_action((const char*) raw_arg);
}
static int do_action_on_thread(const char* arg)
{
pthread_t t;
pthread_create(&t, NULL, thread_callback, (void*) arg);
void* result = NULL;
pthread_join(t, &result);
return (int) (uintptr_t) result;
}
__attribute__((noinline)) static int crash3(int a) {
*((int*) 0xdead) = a;
return a*4;
}
__attribute__((noinline)) static int crash2(int a) {
a = crash3(a) + 2;
return a*3;
}
__attribute__((noinline)) static int crash(int a) {
a = crash2(a) + 1;
return a*2;
}
static void abuse_heap() {
char buf[16];
free((void*) buf); // GCC is smart enough to warn about this, but we're doing it deliberately.
}
static int do_action(const char* arg)
{
fprintf(stderr,"crasher: init pid=%d tid=%d\n", getpid(), gettid());
if (!strncmp(arg, "thread-", strlen("thread-"))) {
return do_action_on_thread(arg + strlen("thread-"));
} else if (!strcmp(arg,"smash-stack")) {
return smash_stack(42);
} else if (!strcmp(arg,"stack-overflow")) {
overflow_stack(NULL);
} else if (!strcmp(arg,"nostack")) {
crashnostack();
} else if (!strcmp(arg,"ctest")) {
return ctest();
} else if (!strcmp(arg,"exit")) {
exit(1);
} else if (!strcmp(arg,"crash")) {
return crash(42);
} else if (!strcmp(arg,"abort")) {
maybeabort();
} else if (!strcmp(arg, "heap-usage")) {
abuse_heap();
}
fprintf(stderr, "%s OP\n", __progname);
fprintf(stderr, "where OP is:\n");
fprintf(stderr, " smash-stack overwrite a stack-guard canary\n");
fprintf(stderr, " stack-overflow recurse until the stack overflows\n");
fprintf(stderr, " heap-corruption cause a libc abort by corrupting the heap\n");
fprintf(stderr, " heap-usage cause a libc abort by abusing a heap function\n");
fprintf(stderr, " nostack crash with a NULL stack pointer\n");
fprintf(stderr, " ctest (obsoleted by thread-crash?)\n");
fprintf(stderr, " exit call exit(1)\n");
fprintf(stderr, " crash cause a SIGSEGV\n");
fprintf(stderr, " abort call abort()\n");
fprintf(stderr, "prefix any of the above with 'thread-' to not run\n");
fprintf(stderr, "on the process' main thread.\n");
return EXIT_SUCCESS;
}
int main(int argc, char **argv)
{
fprintf(stderr,"crasher: built at " __TIME__ "!@\n");
if(argc > 1) {
return do_action(argv[1]);
} else {
crash1();
}
return 0;
}
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