// https://syzkaller.appspot.com/bug?id=3c27eae7bdba97293b68e79c9700ac110f977eed // autogenerated by syzkaller (http://github.com/google/syzkaller) #define _GNU_SOURCE #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include __attribute__((noreturn)) static void doexit(int status) { volatile unsigned i; syscall(__NR_exit_group, status); for (i = 0;; i++) { } } #include #include #include #include #include #include #include const int kFailStatus = 67; const int kRetryStatus = 69; static void fail(const char* msg, ...) { int e = errno; va_list args; va_start(args, msg); vfprintf(stderr, msg, args); va_end(args); fprintf(stderr, " (errno %d)\n", e); doexit((e == ENOMEM || e == EAGAIN) ? kRetryStatus : kFailStatus); } static void use_temporary_dir() { char tmpdir_template[] = "./syzkaller.XXXXXX"; char* tmpdir = mkdtemp(tmpdir_template); if (!tmpdir) fail("failed to mkdtemp"); if (chmod(tmpdir, 0777)) fail("failed to chmod"); if (chdir(tmpdir)) fail("failed to chdir"); } static void loop(); static void sandbox_common() { prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0); setpgrp(); setsid(); struct rlimit rlim; rlim.rlim_cur = rlim.rlim_max = 128 << 20; setrlimit(RLIMIT_AS, &rlim); rlim.rlim_cur = rlim.rlim_max = 8 << 20; setrlimit(RLIMIT_MEMLOCK, &rlim); rlim.rlim_cur = rlim.rlim_max = 32 << 20; setrlimit(RLIMIT_FSIZE, &rlim); rlim.rlim_cur = rlim.rlim_max = 1 << 20; setrlimit(RLIMIT_STACK, &rlim); rlim.rlim_cur = rlim.rlim_max = 0; setrlimit(RLIMIT_CORE, &rlim); if (unshare(CLONE_NEWNS)) { } if (unshare(CLONE_NEWIPC)) { } if (unshare(0x02000000)) { } if (unshare(CLONE_NEWUTS)) { } if (unshare(CLONE_SYSVSEM)) { } } static int do_sandbox_none(void) { if (unshare(CLONE_NEWPID)) { } int pid = fork(); if (pid < 0) fail("sandbox fork failed"); if (pid) return pid; sandbox_common(); if (unshare(CLONE_NEWNET)) { } loop(); doexit(1); } 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 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); 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; } } } } uint64_t r[2] = {0xffffffffffffffff, 0xffffffffffffffff}; void execute_call(int call) { long res; switch (call) { case 0: syscall(__NR_socketpair, 2, 1, 0x84, 0x20000280); break; case 1: memcpy((void*)0x20000000, "-$", 3); *(uint64_t*)0x20664fc0 = 0; *(uint64_t*)0x20664fc8 = 1; *(uint64_t*)0x20664fd0 = 9; *(uint64_t*)0x20664fd8 = 0; *(uint64_t*)0x20664fe0 = 0; *(uint64_t*)0x20664fe8 = 0; *(uint64_t*)0x20664ff0 = 0; *(uint64_t*)0x20664ff8 = 0; syscall(__NR_mq_open, 0x20000000, 0, 0, 0x20664fc0); break; case 2: syscall(__NR_mmap, 0x20000000, 0xe7e000, 3, 0x31, -1, 0); break; case 3: memcpy((void*)0x20000040, "/proc/self/net/pfkey", 21); syscall(__NR_openat, 0xffffffffffffff9c, 0x20000040, 0x200, 0); break; case 4: memcpy((void*)0x20000080, "/selinux/checkreqprot", 22); syscall(__NR_openat, 0xffffffffffffff9c, 0x20000080, 0x20000, 0); break; case 5: res = syscall(__NR_socket, 0xa, 2, 0); if (res != -1) r[0] = res; break; case 6: res = syscall(__NR_socket, 0x18, 1, 1); if (res != -1) r[1] = res; break; case 7: *(uint16_t*)0x205fafd2 = 0x18; *(uint32_t*)0x205fafd4 = 1; *(uint32_t*)0x205fafd8 = 0; *(uint32_t*)0x205fafdc = r[0]; *(uint16_t*)0x205fafe0 = 2; *(uint16_t*)0x205fafe2 = htobe16(0x4e21); *(uint32_t*)0x205fafe4 = htobe32(0xe0000002); *(uint8_t*)0x205fafe8 = 0; *(uint8_t*)0x205fafe9 = 0; *(uint8_t*)0x205fafea = 0; *(uint8_t*)0x205fafeb = 0; *(uint8_t*)0x205fafec = 0; *(uint8_t*)0x205fafed = 0; *(uint8_t*)0x205fafee = 0; *(uint8_t*)0x205fafef = 0; *(uint32_t*)0x205faff0 = 4; *(uint32_t*)0x205faff4 = 0; *(uint32_t*)0x205faff8 = 2; *(uint32_t*)0x205faffc = 0; syscall(__NR_connect, r[1], 0x205fafd2, 0x2e); break; case 8: syscall(__NR_close, r[0]); break; case 9: syscall(__NR_close, r[1]); break; } } void loop() { execute(10); } int main() { syscall(__NR_mmap, 0x20000000, 0x1000000, 3, 0x32, -1, 0); use_temporary_dir(); int pid = do_sandbox_none(); int status = 0; while (waitpid(pid, &status, __WALL) != pid) { } return 0; }