// https://syzkaller.appspot.com/bug?id=d2fe5b3c81cd94ff38fe8a4260f651d5ee5cb4f9 // autogenerated by syzkaller (https://github.com/google/syzkaller) #define _GNU_SOURCE #include <endian.h> #include <errno.h> #include <pthread.h> #include <stdint.h> #include <stdio.h> #include <stdlib.h> #include <string.h> #include <sys/syscall.h> #include <sys/types.h> #include <time.h> #include <unistd.h> #include <linux/futex.h> static void sleep_ms(uint64_t ms) { usleep(ms * 1000); } static uint64_t current_time_ms(void) { struct timespec ts; if (clock_gettime(CLOCK_MONOTONIC, &ts)) exit(1); return (uint64_t)ts.tv_sec * 1000 + (uint64_t)ts.tv_nsec / 1000000; } static void thread_start(void* (*fn)(void*), void* arg) { pthread_t th; pthread_attr_t attr; pthread_attr_init(&attr); pthread_attr_setstacksize(&attr, 128 << 10); int i = 0; for (; i < 100; i++) { if (pthread_create(&th, &attr, fn, arg) == 0) { pthread_attr_destroy(&attr); return; } if (errno == EAGAIN) { usleep(50); continue; } break; } exit(1); } typedef struct { int state; } event_t; static void event_init(event_t* ev) { ev->state = 0; } static void event_reset(event_t* ev) { ev->state = 0; } static void event_set(event_t* ev) { if (ev->state) exit(1); __atomic_store_n(&ev->state, 1, __ATOMIC_RELEASE); syscall(SYS_futex, &ev->state, FUTEX_WAKE | FUTEX_PRIVATE_FLAG, 1000000); } static void event_wait(event_t* ev) { while (!__atomic_load_n(&ev->state, __ATOMIC_ACQUIRE)) syscall(SYS_futex, &ev->state, FUTEX_WAIT | FUTEX_PRIVATE_FLAG, 0, 0); } static int event_isset(event_t* ev) { return __atomic_load_n(&ev->state, __ATOMIC_ACQUIRE); } static int event_timedwait(event_t* ev, uint64_t timeout) { uint64_t start = current_time_ms(); uint64_t now = start; for (;;) { uint64_t remain = timeout - (now - start); struct timespec ts; ts.tv_sec = remain / 1000; ts.tv_nsec = (remain % 1000) * 1000 * 1000; syscall(SYS_futex, &ev->state, FUTEX_WAIT | FUTEX_PRIVATE_FLAG, 0, &ts); if (__atomic_load_n(&ev->state, __ATOMIC_ACQUIRE)) return 1; now = current_time_ms(); if (now - start > timeout) return 0; } } struct thread_t { int created, call; event_t ready, done; }; 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 (;;) { event_wait(&th->ready); event_reset(&th->ready); execute_call(th->call); __atomic_fetch_sub(&running, 1, __ATOMIC_RELAXED); event_set(&th->done); } return 0; } static void loop(void) { if (write(1, "executing program\n", sizeof("executing program\n") - 1)) { } int i, call, thread; for (call = 0; call < 6; call++) { for (thread = 0; thread < (int)(sizeof(threads) / sizeof(threads[0])); thread++) { struct thread_t* th = &threads[thread]; if (!th->created) { th->created = 1; event_init(&th->ready); event_init(&th->done); event_set(&th->done); thread_start(thr, th); } if (!event_isset(&th->done)) continue; event_reset(&th->done); th->call = call; __atomic_fetch_add(&running, 1, __ATOMIC_RELAXED); event_set(&th->ready); event_timedwait(&th->done, 50); break; } } for (i = 0; i < 100 && __atomic_load_n(&running, __ATOMIC_RELAXED); i++) sleep_ms(1); } uint64_t r[1] = {0xffffffffffffffff}; void execute_call(int call) { intptr_t res = 0; switch (call) { case 0: memcpy((void*)0x200000000000, "/sys/devices/virtual/block/nbd13/queue/wbt_lat_usec\000", 52); syscall(__NR_openat, /*fd=*/0xffffffffffffff9cul, /*file=*/0x200000000000ul, /*flags=O_RDWR*/ 2, /*mode=*/0); break; case 1: syscall(__NR_mmap, /*addr=*/0ul, /*len=*/0x400008ul, /*prot=*/0xdful, /*flags=*/0x9b72ul, /*fd=*/2, /*off=*/0x8000ul); break; case 2: res = syscall(__NR_socket, /*domain=AF_NETLINK*/ 0x10ul, /*type=SOCK_DGRAM*/ 2ul, /*proto=*/0); if (res != -1) r[0] = res; break; case 3: *(uint64_t*)0x200000000240 = 0; *(uint32_t*)0x200000000248 = 0; *(uint64_t*)0x200000000250 = 0x200000000200; *(uint64_t*)0x200000000200 = 0x200000000300; memcpy((void*)0x200000000300, " \000\000\000", 4); memcpy((void*)0x200000000304, "\x12\x00", 2); memset((void*)0x200000000306, 93, 1); *(uint64_t*)0x200000000208 = 0x1ac; *(uint64_t*)0x200000000258 = 1; *(uint64_t*)0x200000000260 = 0; *(uint64_t*)0x200000000268 = 0; *(uint32_t*)0x200000000270 = 0; syscall(__NR_sendmsg, /*fd=*/r[0], /*msg=*/0x200000000240ul, /*f=MSG_BATCH*/ 0x40000ul); break; case 4: *(uint64_t*)0x200000000140 = 0; *(uint32_t*)0x200000000148 = 1; *(uint64_t*)0x200000000150 = 0x200000000080; *(uint64_t*)0x200000000080 = 0; *(uint64_t*)0x200000000088 = 0x400; *(uint64_t*)0x200000000158 = 5; *(uint64_t*)0x200000000160 = 0; *(uint64_t*)0x200000000168 = 0x200002; *(uint32_t*)0x200000000170 = 8; *(uint32_t*)0x200000000178 = 0x803; syscall(__NR_recvmmsg, /*fd=*/r[0], /*mmsg=*/0x200000000140ul, /*vlen=*/0xfffffff9, /*flags=*/0x10, /*timeout=*/0ul); break; case 5: syscall(__NR_write, /*fd=*/3, /*buf=*/0ul, /*count=*/0xfffffdeful); break; } } int main(void) { syscall(__NR_mmap, /*addr=*/0x1ffffffff000ul, /*len=*/0x1000ul, /*prot=*/0ul, /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul, /*fd=*/(intptr_t)-1, /*offset=*/0ul); syscall(__NR_mmap, /*addr=*/0x200000000000ul, /*len=*/0x1000000ul, /*prot=PROT_WRITE|PROT_READ|PROT_EXEC*/ 7ul, /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul, /*fd=*/(intptr_t)-1, /*offset=*/0ul); syscall(__NR_mmap, /*addr=*/0x200001000000ul, /*len=*/0x1000ul, /*prot=*/0ul, /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul, /*fd=*/(intptr_t)-1, /*offset=*/0ul); const char* reason; (void)reason; loop(); return 0; }