// 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 __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 uint64_t current_time_ms() { struct timespec ts; if (clock_gettime(CLOCK_MONOTONIC, &ts)) fail("clock_gettime failed"); return (uint64_t)ts.tv_sec * 1000 + (uint64_t)ts.tv_nsec / 1000000; } static void test(); void loop() { int iter; for (iter = 0;; iter++) { int pid = fork(); if (pid < 0) fail("loop fork failed"); if (pid == 0) { prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0); setpgrp(); test(); doexit(0); } int status = 0; uint64_t start = current_time_ms(); for (;;) { int res = waitpid(-1, &status, __WALL | WNOHANG); if (res == pid) break; usleep(1000); if (current_time_ms() - start > 5 * 1000) { kill(-pid, SIGKILL); kill(pid, SIGKILL); while (waitpid(-1, &status, __WALL) != pid) { } break; } } } } 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_openat #define __NR_openat 295 #endif #ifndef __NR_ioctl #define __NR_ioctl 54 #endif #ifndef __NR_clock_gettime #define __NR_clock_gettime 265 #endif #undef __NR_mmap #define __NR_mmap __NR_mmap2 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*)0x20000ff7, "/dev/kvm", 9); r[0] = syscall(__NR_openat, 0xffffff9c, 0x20000ff7, 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: syscall(__NR_clock_gettime, 0, 0x20000000); break; case 5: *(uint32_t*)0x20001000 = 0x10005; *(uint32_t*)0x20001004 = 0; *(uint64_t*)0x20001008 = 0; *(uint64_t*)0x20001010 = 0x2000; *(uint32_t*)0x20001018 = 0x20000000; syscall(__NR_ioctl, r[1], 0x4020ae46, 0x20001000); break; case 6: syscall(__NR_ioctl, r[2], 0xaeb7); 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 (;;) { loop(); } } } sleep(1000000); return 0; }