// https://syzkaller.appspot.com/bug?id=4d86d7ffb1fd63cc638602b45d9998323856981c // autogenerated by syzkaller (https://github.com/google/syzkaller) #define _GNU_SOURCE #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include static unsigned long long procid; 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; for (i = 0; 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; } } static bool write_file(const char* file, const char* what, ...) { char buf[1024]; va_list args; va_start(args, what); vsnprintf(buf, sizeof(buf), what, args); va_end(args); buf[sizeof(buf) - 1] = 0; int len = strlen(buf); int fd = open(file, O_WRONLY | O_CLOEXEC); if (fd == -1) return false; if (write(fd, buf, len) != len) { int err = errno; close(fd); errno = err; return false; } close(fd); return true; } static void kill_and_wait(int pid, int* status) { kill(-pid, SIGKILL); kill(pid, SIGKILL); int i; for (i = 0; i < 100; i++) { if (waitpid(-1, status, WNOHANG | __WALL) == pid) return; usleep(1000); } DIR* dir = opendir("/sys/fs/fuse/connections"); if (dir) { for (;;) { struct dirent* ent = readdir(dir); if (!ent) break; if (strcmp(ent->d_name, ".") == 0 || strcmp(ent->d_name, "..") == 0) continue; char abort[300]; snprintf(abort, sizeof(abort), "/sys/fs/fuse/connections/%s/abort", ent->d_name); int fd = open(abort, O_WRONLY); if (fd == -1) { continue; } if (write(fd, abort, 1) < 0) { } close(fd); } closedir(dir); } else { } while (waitpid(-1, status, __WALL) != pid) { } } static void setup_test() { prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0); setpgrp(); write_file("/proc/self/oom_score_adj", "1000"); } 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 execute_one(void) { int i, call, thread; int collide = 0; again: for (call = 0; call < 7; 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); if (collide && (call % 2) == 0) break; event_timedwait(&th->done, 45); break; } } for (i = 0; i < 100 && __atomic_load_n(&running, __ATOMIC_RELAXED); i++) sleep_ms(1); if (!collide) { collide = 1; goto again; } } static void execute_one(void); #define WAIT_FLAGS __WALL static void loop(void) { int iter; for (iter = 0;; iter++) { int pid = fork(); if (pid < 0) exit(1); if (pid == 0) { setup_test(); execute_one(); exit(0); } int status = 0; uint64_t start = current_time_ms(); for (;;) { if (waitpid(-1, &status, WNOHANG | WAIT_FLAGS) == pid) break; sleep_ms(1); if (current_time_ms() - start < 5 * 1000) continue; kill_and_wait(pid, &status); break; } } } uint64_t r[2] = {0xffffffffffffffff, 0xffffffffffffffff}; void execute_call(int call) { intptr_t res; switch (call) { case 0: syscall(__NR_socket, 0xaul, 1ul, 0); break; case 1: syscall(__NR_mmap, 0x20000000ul, 0xb36000ul, 3ul, 0x8031ul, -1, 0ul); break; case 2: res = syscall(__NR_socket, 0x26ul, 5ul, 0); if (res != -1) r[0] = res; break; case 3: *(uint16_t*)0x20000280 = 0x26; memcpy((void*)0x20000282, "hash\000\000\000\000\000\000\000\000\000\000", 14); *(uint32_t*)0x20000290 = 0; *(uint32_t*)0x20000294 = 0; memcpy((void*)0x20000298, "cryptd(sha224-generic)" "\000\000\000\000\000\000\000\000\000\000\000\000" "\000\000\000\000\000\000\000\000\000\000\000\000" "\000\000\000\000\000\000\000\000\000\000\000\000" "\000\000\000\000\000\000", 64); syscall(__NR_bind, r[0], 0x20000280ul, 0x58ul); break; case 4: res = syscall(__NR_accept4, r[0], 0ul, 0ul, 0ul); if (res != -1) r[1] = res; break; case 5: *(uint64_t*)0x200002c0 = 0x20000000; *(uint16_t*)0x20000000 = 0x10; *(uint16_t*)0x20000002 = 0; *(uint32_t*)0x20000004 = 0; *(uint32_t*)0x20000008 = 0; *(uint32_t*)0x200002c8 = 0xc; *(uint64_t*)0x200002d0 = 0x20000280; *(uint64_t*)0x20000280 = 0x20000100; memcpy((void*)0x20000100, "\xb1\xaa\x26\x11\x86\x95\x81\x81\x10\x50\x5f\x5f\x38\xa4\x08\x00" "\x00\x00\x0f\x6f\x87\x97\xe2\x34\x50\xba\xc0\x73\x1d\xba\xc2\xf1" "\x3f\x7e\x74\x54\xaf\x4f\x58\x53\xc9\x88\xbd\xd2\xdd\xb4\x01\x8c" "\x5a\x53\x65\x16\xe0\xa8\x56\xd1\x10\x23\x4b\xf6\x01\x00\x00\x00" "\x00\x00\x00\x45\xa5\x44\x8b\xe4\xc4\xf3\x7c\x8c\xcb\x37\xe4\x5f" "\x13\x6c\x97\x65\x34\xe1\x89\xfe\x31\x04\x7d\xe8\x03\xf7\x68\x9e" "\x00\x00\x00\x1f\x00\x00\x00\x00\x00\x00\x00\x00\x00\xc2\xe3\x8f" "\x0b\xdb\x5a\x01\x49\x4a\x34\x3b\xd2\x2e\x43\x7f\x61\xb9\x7f\xef" "\x0f\xe7\x59\xcf\xb3\xef\x52\xef\xcd\x30\xe2\xd3\xac\x1c\x92\x49" "\x8b\x69\xde\x06\xe1\x0c\xc8\x9b\xe1\xdb\x8a\xcd\xa4\x61\xe8\xce" "\x61\x02\x00\x8f\x32\x56\xf4\x08\xbb\x30\xb9\x05\x59\x09\x2a\x9d" "\x0a\xdf\x4a\x64\x59\x4b\x84\xc2\x5e\x10\xed\x28\x90\x7d\xa5\xab" "\xb1\x01", 194); *(uint64_t*)0x20000288 = 0x20002154; *(uint64_t*)0x200002d8 = 1; *(uint64_t*)0x200002e0 = 0; *(uint64_t*)0x200002e8 = 0; *(uint32_t*)0x200002f0 = 0; syscall(__NR_sendmsg, r[1], 0x200002c0ul, 0ul); break; case 6: syscall(__NR_madvise, 0x20000000ul, 0x600003ul, 9ul); break; } } int main(void) { syscall(__NR_mmap, 0x20000000ul, 0x1000000ul, 3ul, 0x32ul, -1, 0ul); for (procid = 0; procid < 6; procid++) { if (fork() == 0) { loop(); } } sleep(1000000); return 0; }