// https://syzkaller.appspot.com/bug?id=2b6a5e7ed9c189aadc974fc5ff168b131c005947 // 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 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 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 = 1 << 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); #define CLONE_NEWCGROUP 0x02000000 unshare(CLONE_NEWNS); unshare(CLONE_NEWIPC); unshare(CLONE_NEWCGROUP); unshare(CLONE_NEWNET); unshare(CLONE_NEWUTS); unshare(CLONE_SYSVSEM); } static int do_sandbox_none(int executor_pid, bool enable_tun) { unshare(CLONE_NEWPID); int pid = fork(); if (pid < 0) fail("sandbox fork failed"); if (pid) return pid; sandbox_common(); loop(); doexit(1); } 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; } } } } long r[3]; 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*)0x2099fff7, "/dev/kvm", 9); r[0] = syscall(__NR_openat, 0xffffffffffffff9c, 0x2099fff7, 0, 0); break; case 2: r[1] = syscall(__NR_ioctl, r[0], 0xae01, 0); break; case 3: r[2] = syscall(__NR_ioctl, r[1], 0xae41, 0); break; case 4: *(uint32_t*)0x20c18000 = 0x10000; *(uint32_t*)0x20c18004 = 0; *(uint64_t*)0x20c18008 = 0; *(uint64_t*)0x20c18010 = 0x1000; *(uint64_t*)0x20c18018 = 0x20a98000; syscall(__NR_ioctl, r[1], 0x4020ae46, 0x20c18000); break; case 5: syscall(__NR_ioctl, r[2], 0xaeb7); break; case 6: *(uint32_t*)0x20609000 = 0x3fffd; *(uint32_t*)0x20609004 = 0; *(uint64_t*)0x20609008 = 0; *(uint64_t*)0x20609010 = 0; *(uint64_t*)0x20609018 = 0; *(uint64_t*)0x20609020 = 3; *(uint64_t*)0x20609028 = 1; *(uint64_t*)0x20609030 = 0; *(uint64_t*)0x20609038 = 0; *(uint64_t*)0x20609040 = 3; syscall(__NR_ioctl, r[2], 0x4048ae9b, 0x20609000); break; case 7: syscall(__NR_ioctl, r[2], 0xae80, 0); break; case 8: syscall(__NR_ioctl, r[2], 0xae80, 0); break; } } void test() { memset(r, -1, sizeof(r)); execute(9); collide = 1; execute(9); } int main() { for (procid = 0; procid < 8; procid++) { if (fork() == 0) { for (;;) { int pid = do_sandbox_none(procid, false); int status = 0; while (waitpid(pid, &status, __WALL) != pid) { } } } } sleep(1000000); return 0; }