// https://syzkaller.appspot.com/bug?id=c2be48c653fee8b658c47350c317e480b50ced41 // 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 #include #include #include #include #include #include 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); } #define BITMASK(bf_off, bf_len) (((1ull << (bf_len)) - 1) << (bf_off)) #define STORE_BY_BITMASK(type, htobe, addr, val, bf_off, bf_len) \ *(type*)(addr) = \ htobe((htobe(*(type*)(addr)) & ~BITMASK((bf_off), (bf_len))) | \ (((type)(val) << (bf_off)) & BITMASK((bf_off), (bf_len)))) 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 nlmsg { char* pos; int nesting; struct nlattr* nested[8]; char buf[4096]; }; static void netlink_init(struct nlmsg* nlmsg, int typ, int flags, const void* data, int size) { memset(nlmsg, 0, sizeof(*nlmsg)); struct nlmsghdr* hdr = (struct nlmsghdr*)nlmsg->buf; hdr->nlmsg_type = typ; hdr->nlmsg_flags = NLM_F_REQUEST | NLM_F_ACK | flags; memcpy(hdr + 1, data, size); nlmsg->pos = (char*)(hdr + 1) + NLMSG_ALIGN(size); } static void netlink_attr(struct nlmsg* nlmsg, int typ, const void* data, int size) { struct nlattr* attr = (struct nlattr*)nlmsg->pos; attr->nla_len = sizeof(*attr) + size; attr->nla_type = typ; if (size > 0) memcpy(attr + 1, data, size); nlmsg->pos += NLMSG_ALIGN(attr->nla_len); } static int netlink_send_ext(struct nlmsg* nlmsg, int sock, uint16_t reply_type, int* reply_len, bool dofail) { if (nlmsg->pos > nlmsg->buf + sizeof(nlmsg->buf) || nlmsg->nesting) exit(1); struct nlmsghdr* hdr = (struct nlmsghdr*)nlmsg->buf; hdr->nlmsg_len = nlmsg->pos - nlmsg->buf; struct sockaddr_nl addr; memset(&addr, 0, sizeof(addr)); addr.nl_family = AF_NETLINK; ssize_t n = sendto(sock, nlmsg->buf, hdr->nlmsg_len, 0, (struct sockaddr*)&addr, sizeof(addr)); if (n != (ssize_t)hdr->nlmsg_len) { if (dofail) exit(1); return -1; } n = recv(sock, nlmsg->buf, sizeof(nlmsg->buf), 0); if (reply_len) *reply_len = 0; if (n < 0) { if (dofail) exit(1); return -1; } if (n < (ssize_t)sizeof(struct nlmsghdr)) { errno = EINVAL; if (dofail) exit(1); return -1; } if (hdr->nlmsg_type == NLMSG_DONE) return 0; if (reply_len && hdr->nlmsg_type == reply_type) { *reply_len = n; return 0; } if (n < (ssize_t)(sizeof(struct nlmsghdr) + sizeof(struct nlmsgerr))) { errno = EINVAL; if (dofail) exit(1); return -1; } if (hdr->nlmsg_type != NLMSG_ERROR) { errno = EINVAL; if (dofail) exit(1); return -1; } errno = -((struct nlmsgerr*)(hdr + 1))->error; return -errno; } static int netlink_query_family_id(struct nlmsg* nlmsg, int sock, const char* family_name, bool dofail) { struct genlmsghdr genlhdr; memset(&genlhdr, 0, sizeof(genlhdr)); genlhdr.cmd = CTRL_CMD_GETFAMILY; netlink_init(nlmsg, GENL_ID_CTRL, 0, &genlhdr, sizeof(genlhdr)); netlink_attr(nlmsg, CTRL_ATTR_FAMILY_NAME, family_name, strnlen(family_name, GENL_NAMSIZ - 1) + 1); int n = 0; int err = netlink_send_ext(nlmsg, sock, GENL_ID_CTRL, &n, dofail); if (err < 0) { return -1; } uint16_t id = 0; struct nlattr* attr = (struct nlattr*)(nlmsg->buf + NLMSG_HDRLEN + NLMSG_ALIGN(sizeof(genlhdr))); for (; (char*)attr < nlmsg->buf + n; attr = (struct nlattr*)((char*)attr + NLMSG_ALIGN(attr->nla_len))) { if (attr->nla_type == CTRL_ATTR_FAMILY_ID) { id = *(uint16_t*)(attr + 1); break; } } if (!id) { errno = EINVAL; return -1; } recv(sock, nlmsg->buf, sizeof(nlmsg->buf), 0); return id; } static long syz_genetlink_get_family_id(volatile long name, volatile long sock_arg) { bool dofail = false; int fd = sock_arg; if (fd < 0) { dofail = true; fd = socket(AF_NETLINK, SOCK_RAW, NETLINK_GENERIC); if (fd == -1) { return -1; } } struct nlmsg nlmsg_tmp; int ret = netlink_query_family_id(&nlmsg_tmp, fd, (char*)name, dofail); if ((int)sock_arg < 0) close(fd); if (ret < 0) { return -1; } return ret; } 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) { int i, call, thread; 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); event_timedwait(&th->done, 50); break; } } for (i = 0; i < 100 && __atomic_load_n(&running, __ATOMIC_RELAXED); i++) sleep_ms(1); } uint64_t r[3] = {0xffffffffffffffff, 0xffffffffffffffff, 0x0}; void execute_call(int call) { intptr_t res = 0; switch (call) { case 0: res = syscall(__NR_socket, 2ul, 1ul, 0x106); if (res != -1) r[0] = res; break; case 1: syscall(__NR_listen, r[0], 0); break; case 2: syscall(__NR_accept, r[0], 0ul, 0ul); break; case 3: syscall(__NR_connect, r[0], 0ul, 0ul); break; case 4: res = syscall(__NR_socket, 0x10ul, 3ul, 0x10); if (res != -1) r[1] = res; break; case 5: memcpy((void*)0x20000040, "mptcp_pm\000", 9); res = -1; res = syz_genetlink_get_family_id(0x20000040, -1); if (res != -1) r[2] = res; break; case 6: *(uint64_t*)0x20000100 = 0; *(uint32_t*)0x20000108 = 0; *(uint64_t*)0x20000110 = 0x20000000; *(uint64_t*)0x20000000 = 0x20001640; *(uint32_t*)0x20001640 = 0x34; *(uint16_t*)0x20001644 = r[2]; *(uint16_t*)0x20001646 = 0x5625; *(uint32_t*)0x20001648 = 0; *(uint32_t*)0x2000164c = 0; *(uint8_t*)0x20001650 = 2; *(uint8_t*)0x20001651 = 0; *(uint16_t*)0x20001652 = 0; *(uint16_t*)0x20001654 = 0x20; STORE_BY_BITMASK(uint16_t, , 0x20001656, 1, 0, 14); STORE_BY_BITMASK(uint16_t, , 0x20001657, 0, 6, 1); STORE_BY_BITMASK(uint16_t, , 0x20001657, 1, 7, 1); *(uint16_t*)0x20001658 = 0x14; *(uint16_t*)0x2000165a = 4; memset((void*)0x2000165c, 0, 10); memset((void*)0x20001666, 255, 2); *(uint32_t*)0x20001668 = htobe32(0); *(uint16_t*)0x2000166c = 6; *(uint16_t*)0x2000166e = 1; *(uint16_t*)0x20001670 = 0xa; *(uint64_t*)0x20000008 = 0x34; *(uint64_t*)0x20000118 = 1; *(uint64_t*)0x20000120 = 0; *(uint64_t*)0x20000128 = 0; *(uint32_t*)0x20000130 = 0; syscall(__NR_sendmsg, r[1], 0x20000100ul, 0ul); break; } } int main(void) { syscall(__NR_mmap, 0x1ffff000ul, 0x1000ul, 0ul, 0x32ul, -1, 0ul); syscall(__NR_mmap, 0x20000000ul, 0x1000000ul, 7ul, 0x32ul, -1, 0ul); syscall(__NR_mmap, 0x21000000ul, 0x1000ul, 0ul, 0x32ul, -1, 0ul); loop(); return 0; }