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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>
void crash1(void);
void crashnostack(void);
void maybeabort(void);
int do_action(const char* arg);
static void debuggerd_connect()
{
char tmp[1];
int s;
sprintf(tmp, "%d", gettid());
s = socket_local_client("android:debuggerd",
ANDROID_SOCKET_NAMESPACE_ABSTRACT, SOCK_STREAM);
if(s >= 0) {
read(s, tmp, 1);
close(s);
}
}
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 unpredicatable
// 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]);
}
void test_call1()
{
*((int*) 32) = 1;
}
void *test_thread(void *x)
{
printf("crasher: thread pid=%d tid=%d\n", getpid(), gettid());
sleep(1);
test_call1();
printf("goodbye\n");
return 0;
}
void *noisy(void *x)
{
char c = (unsigned) x;
for(;;) {
usleep(250*1000);
write(2, &c, 1);
if(c == 'C') *((unsigned*) 0) = 42;
}
return 0;
}
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*) do_action((const char*) raw_arg);
}
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) result;
}
__attribute__((noinline)) int crash3(int a) {
*((int*) 0xdead) = a;
return a*4;
}
__attribute__((noinline)) int crash2(int a) {
a = crash3(a) + 2;
return a*3;
}
__attribute__((noinline)) int crash(int a) {
a = crash2(a) + 1;
return a*2;
}
int do_action(const char* arg)
{
if(!strncmp(arg, "thread-", strlen("thread-"))) {
return do_action_on_thread(arg + strlen("thread-"));
}
if(!strcmp(arg,"smash-stack")) return smash_stack(42);
if(!strcmp(arg,"nostack")) crashnostack();
if(!strcmp(arg,"ctest")) return ctest();
if(!strcmp(arg,"exit")) exit(1);
if(!strcmp(arg,"crash")) return crash(42);
if(!strcmp(arg,"abort")) maybeabort();
pthread_t thr;
pthread_attr_t attr;
pthread_attr_init(&attr);
pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
pthread_create(&thr, &attr, test_thread, 0);
while(1) sleep(1);
}
int main(int argc, char **argv)
{
fprintf(stderr,"crasher: built at " __TIME__ "!@\n");
fprintf(stderr,"crasher: init pid=%d tid=%d\n", getpid(), gettid());
if(argc > 1) {
return do_action(argv[1]);
} else {
crash1();
// *((int*) 0) = 42;
}
return 0;
}
void maybeabort()
{
if(time(0) != 42) abort();
}
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