// https://syzkaller.appspot.com/bug?id=3c1f47967b7cbd399d3ba3e65f297a29aa1c5f92 // autogenerated by syzkaller (http://github.com/google/syzkaller) #define _GNU_SOURCE #include #include #include #include #include #include #include #include #include #include #include #include static uintptr_t syz_open_dev(uintptr_t a0, uintptr_t a1, uintptr_t a2) { if (a0 == 0xc || a0 == 0xb) { char buf[128]; sprintf(buf, "/dev/%s/%d:%d", a0 == 0xc ? "char" : "block", (uint8_t)a1, (uint8_t)a2); return open(buf, O_RDWR, 0); } else { char buf[1024]; char* hash; strncpy(buf, (char*)a0, sizeof(buf)); buf[sizeof(buf) - 1] = 0; while ((hash = strchr(buf, '#'))) { *hash = '0' + (char)(a1 % 10); a1 /= 10; } return open(buf, a2, 0); } } static void test(); void loop() { while (1) { test(); } } struct thread_t { int created, running, call; pthread_t th; }; static struct thread_t threads[16]; static void execute_call(int call); static int running; static int collide; static void* thr(void* arg) { struct thread_t* th = (struct thread_t*)arg; for (;;) { while (!__atomic_load_n(&th->running, __ATOMIC_ACQUIRE)) syscall(SYS_futex, &th->running, FUTEX_WAIT, 0, 0); execute_call(th->call); __atomic_fetch_sub(&running, 1, __ATOMIC_RELAXED); __atomic_store_n(&th->running, 0, __ATOMIC_RELEASE); syscall(SYS_futex, &th->running, FUTEX_WAKE); } return 0; } static void execute(int num_calls) { int call, thread; running = 0; for (call = 0; call < num_calls; call++) { for (thread = 0; thread < sizeof(threads) / sizeof(threads[0]); thread++) { struct thread_t* th = &threads[thread]; if (!th->created) { th->created = 1; pthread_attr_t attr; pthread_attr_init(&attr); pthread_attr_setstacksize(&attr, 128 << 10); pthread_create(&th->th, &attr, thr, th); } if (!__atomic_load_n(&th->running, __ATOMIC_ACQUIRE)) { th->call = call; __atomic_fetch_add(&running, 1, __ATOMIC_RELAXED); __atomic_store_n(&th->running, 1, __ATOMIC_RELEASE); syscall(SYS_futex, &th->running, FUTEX_WAKE); if (collide && call % 2) break; struct timespec ts; ts.tv_sec = 0; ts.tv_nsec = 20 * 1000 * 1000; syscall(SYS_futex, &th->running, FUTEX_WAIT, 1, &ts); if (running) usleep((call == num_calls - 1) ? 10000 : 1000); break; } } } } #ifndef __NR_mmap #define __NR_mmap 192 #endif #ifndef __NR_write #define __NR_write 4 #endif #ifndef __NR_readv #define __NR_readv 145 #endif #undef __NR_mmap #define __NR_mmap __NR_mmap2 long r[1]; uint64_t procid; void execute_call(int call) { switch (call) { case 0: syscall(__NR_mmap, 0x20000000, 0xfff000, 3, 0x32, -1, 0); break; case 1: memcpy((void*)0x20005000, "/dev/sg#", 9); r[0] = syz_open_dev(0x20005000, 0, 0x8002); break; case 2: memcpy((void*)0x20a75f9f, "\xb6\x3d\xb8\x5e\x1e\x8d\x00\x00\x00\x01\xb2\x9d\x00\x54\x06\xec" "\xff\xff\xff\x00\x00\x00\x00\x00\x06\x01\x9b\x97\x2d\x21\x07\x4d" "\x87\x30\x67\x8f\xe2\x2c\x9b\x16\x00\x00\x01\x00\xae\x1a\x56\x9d" "\xa1\xad\x47\x25\x19\x62\x88\x5f\x4e\x42\x8d\xaa\xc5\x67\x15\x49" "\xe2\x57\x22\xd0\xc7\x7a\x03\x76\x7e\x0b\x52\xd0\x9e\xc4\xa3\xff" "\xcf\x48\x88\xd4\xe2\x22\x42\xb7\x18\xcb\x3f\x09\xee\x42\x96\x39", 96); syscall(__NR_write, r[0], 0x20a75f9f, 0x60); break; case 3: *(uint32_t*)0x204d7fa0 = 0x20aaaf6b; *(uint32_t*)0x204d7fa4 = 0x95; syscall(__NR_readv, r[0], 0x204d7fa0, 1); break; } } void test() { memset(r, -1, sizeof(r)); execute(4); collide = 1; execute(4); } int main() { for (procid = 0; procid < 8; procid++) { if (fork() == 0) { for (;;) { loop(); } } } sleep(1000000); return 0; }