// https://syzkaller.appspot.com/bug?id=3aaddbe5d3d25b4eacc99024fe9bcee40c587477 // 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 #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 use_temporary_dir(void) { char tmpdir_template[] = "./syzkaller.XXXXXX"; char* tmpdir = mkdtemp(tmpdir_template); if (!tmpdir) exit(1); if (chmod(tmpdir, 0777)) exit(1); if (chdir(tmpdir)) exit(1); } 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; } } 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; } 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 void netlink_nest(struct nlmsg* nlmsg, int typ) { struct nlattr* attr = (struct nlattr*)nlmsg->pos; attr->nla_type = typ; nlmsg->pos += sizeof(*attr); nlmsg->nested[nlmsg->nesting++] = attr; } static void netlink_done(struct nlmsg* nlmsg) { struct nlattr* attr = nlmsg->nested[--nlmsg->nesting]; attr->nla_len = nlmsg->pos - (char*)attr; } 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_send(struct nlmsg* nlmsg, int sock) { return netlink_send_ext(nlmsg, sock, 0, NULL, true); } 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 void netlink_add_device_impl(struct nlmsg* nlmsg, const char* type, const char* name, bool up) { struct ifinfomsg hdr; memset(&hdr, 0, sizeof(hdr)); if (up) hdr.ifi_flags = hdr.ifi_change = IFF_UP; netlink_init(nlmsg, RTM_NEWLINK, NLM_F_EXCL | NLM_F_CREATE, &hdr, sizeof(hdr)); if (name) netlink_attr(nlmsg, IFLA_IFNAME, name, strlen(name)); netlink_nest(nlmsg, IFLA_LINKINFO); netlink_attr(nlmsg, IFLA_INFO_KIND, type, strlen(type)); } static void netlink_device_change(struct nlmsg* nlmsg, int sock, const char* name, bool up, const char* master, const void* mac, int macsize, const char* new_name) { struct ifinfomsg hdr; memset(&hdr, 0, sizeof(hdr)); if (up) hdr.ifi_flags = hdr.ifi_change = IFF_UP; hdr.ifi_index = if_nametoindex(name); netlink_init(nlmsg, RTM_NEWLINK, 0, &hdr, sizeof(hdr)); if (new_name) netlink_attr(nlmsg, IFLA_IFNAME, new_name, strlen(new_name)); if (master) { int ifindex = if_nametoindex(master); netlink_attr(nlmsg, IFLA_MASTER, &ifindex, sizeof(ifindex)); } if (macsize) netlink_attr(nlmsg, IFLA_ADDRESS, mac, macsize); int err = netlink_send(nlmsg, sock); if (err < 0) { } } static int netlink_add_addr(struct nlmsg* nlmsg, int sock, const char* dev, const void* addr, int addrsize) { struct ifaddrmsg hdr; memset(&hdr, 0, sizeof(hdr)); hdr.ifa_family = addrsize == 4 ? AF_INET : AF_INET6; hdr.ifa_prefixlen = addrsize == 4 ? 24 : 120; hdr.ifa_scope = RT_SCOPE_UNIVERSE; hdr.ifa_index = if_nametoindex(dev); netlink_init(nlmsg, RTM_NEWADDR, NLM_F_CREATE | NLM_F_REPLACE, &hdr, sizeof(hdr)); netlink_attr(nlmsg, IFA_LOCAL, addr, addrsize); netlink_attr(nlmsg, IFA_ADDRESS, addr, addrsize); return netlink_send(nlmsg, sock); } static void netlink_add_addr4(struct nlmsg* nlmsg, int sock, const char* dev, const char* addr) { struct in_addr in_addr; inet_pton(AF_INET, addr, &in_addr); int err = netlink_add_addr(nlmsg, sock, dev, &in_addr, sizeof(in_addr)); if (err < 0) { } } static void netlink_add_addr6(struct nlmsg* nlmsg, int sock, const char* dev, const char* addr) { struct in6_addr in6_addr; inet_pton(AF_INET6, addr, &in6_addr); int err = netlink_add_addr(nlmsg, sock, dev, &in6_addr, sizeof(in6_addr)); if (err < 0) { } } static void netlink_add_neigh(struct nlmsg* nlmsg, int sock, const char* name, const void* addr, int addrsize, const void* mac, int macsize) { struct ndmsg hdr; memset(&hdr, 0, sizeof(hdr)); hdr.ndm_family = addrsize == 4 ? AF_INET : AF_INET6; hdr.ndm_ifindex = if_nametoindex(name); hdr.ndm_state = NUD_PERMANENT; netlink_init(nlmsg, RTM_NEWNEIGH, NLM_F_EXCL | NLM_F_CREATE, &hdr, sizeof(hdr)); netlink_attr(nlmsg, NDA_DST, addr, addrsize); netlink_attr(nlmsg, NDA_LLADDR, mac, macsize); int err = netlink_send(nlmsg, sock); if (err < 0) { } } static struct nlmsg nlmsg; static int tunfd = -1; #define TUN_IFACE "syz_tun" #define LOCAL_MAC 0xaaaaaaaaaaaa #define REMOTE_MAC 0xaaaaaaaaaabb #define LOCAL_IPV4 "172.20.20.170" #define REMOTE_IPV4 "172.20.20.187" #define LOCAL_IPV6 "fe80::aa" #define REMOTE_IPV6 "fe80::bb" #define IFF_NAPI 0x0010 static void initialize_tun(void) { tunfd = open("/dev/net/tun", O_RDWR | O_NONBLOCK); if (tunfd == -1) { printf("tun: can't open /dev/net/tun: please enable CONFIG_TUN=y\n"); printf("otherwise fuzzing or reproducing might not work as intended\n"); return; } const int kTunFd = 200; if (dup2(tunfd, kTunFd) < 0) exit(1); close(tunfd); tunfd = kTunFd; struct ifreq ifr; memset(&ifr, 0, sizeof(ifr)); strncpy(ifr.ifr_name, TUN_IFACE, IFNAMSIZ); ifr.ifr_flags = IFF_TAP | IFF_NO_PI; if (ioctl(tunfd, TUNSETIFF, (void*)&ifr) < 0) { exit(1); } char sysctl[64]; sprintf(sysctl, "/proc/sys/net/ipv6/conf/%s/accept_dad", TUN_IFACE); write_file(sysctl, "0"); sprintf(sysctl, "/proc/sys/net/ipv6/conf/%s/router_solicitations", TUN_IFACE); write_file(sysctl, "0"); int sock = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE); if (sock == -1) exit(1); netlink_add_addr4(&nlmsg, sock, TUN_IFACE, LOCAL_IPV4); netlink_add_addr6(&nlmsg, sock, TUN_IFACE, LOCAL_IPV6); uint64_t macaddr = REMOTE_MAC; struct in_addr in_addr; inet_pton(AF_INET, REMOTE_IPV4, &in_addr); netlink_add_neigh(&nlmsg, sock, TUN_IFACE, &in_addr, sizeof(in_addr), &macaddr, ETH_ALEN); struct in6_addr in6_addr; inet_pton(AF_INET6, REMOTE_IPV6, &in6_addr); netlink_add_neigh(&nlmsg, sock, TUN_IFACE, &in6_addr, sizeof(in6_addr), &macaddr, ETH_ALEN); macaddr = LOCAL_MAC; netlink_device_change(&nlmsg, sock, TUN_IFACE, true, 0, &macaddr, ETH_ALEN, NULL); close(sock); } const int kInitNetNsFd = 201; #define WIFI_INITIAL_DEVICE_COUNT 2 #define WIFI_MAC_BASE \ { \ 0x08, 0x02, 0x11, 0x00, 0x00, 0x00 \ } #define WIFI_IBSS_BSSID \ { \ 0x50, 0x50, 0x50, 0x50, 0x50, 0x50 \ } #define WIFI_IBSS_SSID \ { \ 0x10, 0x10, 0x10, 0x10, 0x10, 0x10 \ } #define WIFI_DEFAULT_FREQUENCY 2412 #define WIFI_DEFAULT_SIGNAL 0 #define WIFI_DEFAULT_RX_RATE 1 #define HWSIM_CMD_REGISTER 1 #define HWSIM_CMD_FRAME 2 #define HWSIM_CMD_NEW_RADIO 4 #define HWSIM_ATTR_SUPPORT_P2P_DEVICE 14 #define HWSIM_ATTR_PERM_ADDR 22 #define IF_OPER_UP 6 struct join_ibss_props { int wiphy_freq; bool wiphy_freq_fixed; uint8_t* mac; uint8_t* ssid; int ssid_len; }; static int set_interface_state(const char* interface_name, int on) { struct ifreq ifr; int sock = socket(AF_INET, SOCK_DGRAM, 0); if (sock < 0) { return -1; } memset(&ifr, 0, sizeof(ifr)); strcpy(ifr.ifr_name, interface_name); int ret = ioctl(sock, SIOCGIFFLAGS, &ifr); if (ret < 0) { close(sock); return -1; } if (on) ifr.ifr_flags |= IFF_UP; else ifr.ifr_flags &= ~IFF_UP; ret = ioctl(sock, SIOCSIFFLAGS, &ifr); close(sock); if (ret < 0) { return -1; } return 0; } static int nl80211_set_interface(struct nlmsg* nlmsg, int sock, int nl80211_family, uint32_t ifindex, uint32_t iftype) { struct genlmsghdr genlhdr; memset(&genlhdr, 0, sizeof(genlhdr)); genlhdr.cmd = NL80211_CMD_SET_INTERFACE; netlink_init(nlmsg, nl80211_family, 0, &genlhdr, sizeof(genlhdr)); netlink_attr(nlmsg, NL80211_ATTR_IFINDEX, &ifindex, sizeof(ifindex)); netlink_attr(nlmsg, NL80211_ATTR_IFTYPE, &iftype, sizeof(iftype)); int err = netlink_send(nlmsg, sock); if (err < 0) { } return err; } static int nl80211_join_ibss(struct nlmsg* nlmsg, int sock, int nl80211_family, uint32_t ifindex, struct join_ibss_props* props) { struct genlmsghdr genlhdr; memset(&genlhdr, 0, sizeof(genlhdr)); genlhdr.cmd = NL80211_CMD_JOIN_IBSS; netlink_init(nlmsg, nl80211_family, 0, &genlhdr, sizeof(genlhdr)); netlink_attr(nlmsg, NL80211_ATTR_IFINDEX, &ifindex, sizeof(ifindex)); netlink_attr(nlmsg, NL80211_ATTR_SSID, props->ssid, props->ssid_len); netlink_attr(nlmsg, NL80211_ATTR_WIPHY_FREQ, &(props->wiphy_freq), sizeof(props->wiphy_freq)); if (props->mac) netlink_attr(nlmsg, NL80211_ATTR_MAC, props->mac, ETH_ALEN); if (props->wiphy_freq_fixed) netlink_attr(nlmsg, NL80211_ATTR_FREQ_FIXED, NULL, 0); int err = netlink_send(nlmsg, sock); if (err < 0) { } return err; } static int get_ifla_operstate(struct nlmsg* nlmsg, int ifindex) { struct ifinfomsg info; memset(&info, 0, sizeof(info)); info.ifi_family = AF_UNSPEC; info.ifi_index = ifindex; int sock = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE); if (sock == -1) { return -1; } netlink_init(nlmsg, RTM_GETLINK, 0, &info, sizeof(info)); int n; int err = netlink_send_ext(nlmsg, sock, RTM_NEWLINK, &n, true); close(sock); if (err) { return -1; } struct rtattr* attr = IFLA_RTA(NLMSG_DATA(nlmsg->buf)); for (; RTA_OK(attr, n); attr = RTA_NEXT(attr, n)) { if (attr->rta_type == IFLA_OPERSTATE) return *((int32_t*)RTA_DATA(attr)); } return -1; } static int await_ifla_operstate(struct nlmsg* nlmsg, char* interface, int operstate) { int ifindex = if_nametoindex(interface); while (true) { usleep(1000); int ret = get_ifla_operstate(nlmsg, ifindex); if (ret < 0) return ret; if (ret == operstate) return 0; } return 0; } static int nl80211_setup_ibss_interface(struct nlmsg* nlmsg, int sock, int nl80211_family_id, char* interface, struct join_ibss_props* ibss_props) { int ifindex = if_nametoindex(interface); if (ifindex == 0) { return -1; } int ret = nl80211_set_interface(nlmsg, sock, nl80211_family_id, ifindex, NL80211_IFTYPE_ADHOC); if (ret < 0) { return -1; } ret = set_interface_state(interface, 1); if (ret < 0) { return -1; } ret = nl80211_join_ibss(nlmsg, sock, nl80211_family_id, ifindex, ibss_props); if (ret < 0) { return -1; } return 0; } static int hwsim80211_create_device(struct nlmsg* nlmsg, int sock, int hwsim_family, uint8_t mac_addr[ETH_ALEN]) { struct genlmsghdr genlhdr; memset(&genlhdr, 0, sizeof(genlhdr)); genlhdr.cmd = HWSIM_CMD_NEW_RADIO; netlink_init(nlmsg, hwsim_family, 0, &genlhdr, sizeof(genlhdr)); netlink_attr(nlmsg, HWSIM_ATTR_SUPPORT_P2P_DEVICE, NULL, 0); netlink_attr(nlmsg, HWSIM_ATTR_PERM_ADDR, mac_addr, ETH_ALEN); int err = netlink_send(nlmsg, sock); if (err < 0) { } return err; } static void initialize_wifi_devices(void) { int rfkill = open("/dev/rfkill", O_RDWR); if (rfkill == -1) { if (errno != ENOENT && errno != EACCES) exit(1); } else { struct rfkill_event event = {0}; event.type = RFKILL_TYPE_ALL; event.op = RFKILL_OP_CHANGE_ALL; if (write(rfkill, &event, sizeof(event)) != (ssize_t)(sizeof(event))) exit(1); close(rfkill); } uint8_t mac_addr[6] = WIFI_MAC_BASE; int sock = socket(AF_NETLINK, SOCK_RAW, NETLINK_GENERIC); if (sock < 0) { return; } int hwsim_family_id = netlink_query_family_id(&nlmsg, sock, "MAC80211_HWSIM", true); int nl80211_family_id = netlink_query_family_id(&nlmsg, sock, "nl80211", true); uint8_t ssid[] = WIFI_IBSS_SSID; uint8_t bssid[] = WIFI_IBSS_BSSID; struct join_ibss_props ibss_props = {.wiphy_freq = WIFI_DEFAULT_FREQUENCY, .wiphy_freq_fixed = true, .mac = bssid, .ssid = ssid, .ssid_len = sizeof(ssid)}; for (int device_id = 0; device_id < WIFI_INITIAL_DEVICE_COUNT; device_id++) { mac_addr[5] = device_id; int ret = hwsim80211_create_device(&nlmsg, sock, hwsim_family_id, mac_addr); if (ret < 0) exit(1); char interface[6] = "wlan0"; interface[4] += device_id; if (nl80211_setup_ibss_interface(&nlmsg, sock, nl80211_family_id, interface, &ibss_props) < 0) exit(1); } for (int device_id = 0; device_id < WIFI_INITIAL_DEVICE_COUNT; device_id++) { char interface[6] = "wlan0"; interface[4] += device_id; int ret = await_ifla_operstate(&nlmsg, interface, IF_OPER_UP); if (ret < 0) exit(1); } close(sock); } static int runcmdline(char* cmdline) { int ret = system(cmdline); if (ret) { } return ret; } #define MAX_FDS 30 static long syz_init_net_socket(volatile long domain, volatile long type, volatile long proto) { int netns = open("/proc/self/ns/net", O_RDONLY); if (netns == -1) return netns; if (setns(kInitNetNsFd, 0)) return -1; int sock = syscall(__NR_socket, domain, type, proto); int err = errno; if (setns(netns, 0)) exit(1); close(netns); errno = err; return sock; } #define BTPROTO_HCI 1 #define ACL_LINK 1 #define SCAN_PAGE 2 typedef struct { uint8_t b[6]; } __attribute__((packed)) bdaddr_t; #define HCI_COMMAND_PKT 1 #define HCI_EVENT_PKT 4 #define HCI_VENDOR_PKT 0xff struct hci_command_hdr { uint16_t opcode; uint8_t plen; } __attribute__((packed)); struct hci_event_hdr { uint8_t evt; uint8_t plen; } __attribute__((packed)); #define HCI_EV_CONN_COMPLETE 0x03 struct hci_ev_conn_complete { uint8_t status; uint16_t handle; bdaddr_t bdaddr; uint8_t link_type; uint8_t encr_mode; } __attribute__((packed)); #define HCI_EV_CONN_REQUEST 0x04 struct hci_ev_conn_request { bdaddr_t bdaddr; uint8_t dev_class[3]; uint8_t link_type; } __attribute__((packed)); #define HCI_EV_REMOTE_FEATURES 0x0b struct hci_ev_remote_features { uint8_t status; uint16_t handle; uint8_t features[8]; } __attribute__((packed)); #define HCI_EV_CMD_COMPLETE 0x0e struct hci_ev_cmd_complete { uint8_t ncmd; uint16_t opcode; } __attribute__((packed)); #define HCI_OP_WRITE_SCAN_ENABLE 0x0c1a #define HCI_OP_READ_BUFFER_SIZE 0x1005 struct hci_rp_read_buffer_size { uint8_t status; uint16_t acl_mtu; uint8_t sco_mtu; uint16_t acl_max_pkt; uint16_t sco_max_pkt; } __attribute__((packed)); #define HCI_OP_READ_BD_ADDR 0x1009 struct hci_rp_read_bd_addr { uint8_t status; bdaddr_t bdaddr; } __attribute__((packed)); #define HCI_EV_LE_META 0x3e struct hci_ev_le_meta { uint8_t subevent; } __attribute__((packed)); #define HCI_EV_LE_CONN_COMPLETE 0x01 struct hci_ev_le_conn_complete { uint8_t status; uint16_t handle; uint8_t role; uint8_t bdaddr_type; bdaddr_t bdaddr; uint16_t interval; uint16_t latency; uint16_t supervision_timeout; uint8_t clk_accurancy; } __attribute__((packed)); struct hci_dev_req { uint16_t dev_id; uint32_t dev_opt; }; struct vhci_vendor_pkt_request { uint8_t type; uint8_t opcode; } __attribute__((packed)); struct vhci_pkt { uint8_t type; union { struct { uint8_t opcode; uint16_t id; } __attribute__((packed)) vendor_pkt; struct hci_command_hdr command_hdr; }; } __attribute__((packed)); #define HCIDEVUP _IOW('H', 201, int) #define HCISETSCAN _IOW('H', 221, int) static int vhci_fd = -1; static void rfkill_unblock_all() { int fd = open("/dev/rfkill", O_WRONLY); if (fd < 0) exit(1); struct rfkill_event event = {0}; event.idx = 0; event.type = RFKILL_TYPE_ALL; event.op = RFKILL_OP_CHANGE_ALL; event.soft = 0; event.hard = 0; if (write(fd, &event, sizeof(event)) < 0) exit(1); close(fd); } static void hci_send_event_packet(int fd, uint8_t evt, void* data, size_t data_len) { struct iovec iv[3]; struct hci_event_hdr hdr; hdr.evt = evt; hdr.plen = data_len; uint8_t type = HCI_EVENT_PKT; iv[0].iov_base = &type; iv[0].iov_len = sizeof(type); iv[1].iov_base = &hdr; iv[1].iov_len = sizeof(hdr); iv[2].iov_base = data; iv[2].iov_len = data_len; if (writev(fd, iv, sizeof(iv) / sizeof(struct iovec)) < 0) exit(1); } static void hci_send_event_cmd_complete(int fd, uint16_t opcode, void* data, size_t data_len) { struct iovec iv[4]; struct hci_event_hdr hdr; hdr.evt = HCI_EV_CMD_COMPLETE; hdr.plen = sizeof(struct hci_ev_cmd_complete) + data_len; struct hci_ev_cmd_complete evt_hdr; evt_hdr.ncmd = 1; evt_hdr.opcode = opcode; uint8_t type = HCI_EVENT_PKT; iv[0].iov_base = &type; iv[0].iov_len = sizeof(type); iv[1].iov_base = &hdr; iv[1].iov_len = sizeof(hdr); iv[2].iov_base = &evt_hdr; iv[2].iov_len = sizeof(evt_hdr); iv[3].iov_base = data; iv[3].iov_len = data_len; if (writev(fd, iv, sizeof(iv) / sizeof(struct iovec)) < 0) exit(1); } static bool process_command_pkt(int fd, char* buf, ssize_t buf_size) { struct hci_command_hdr* hdr = (struct hci_command_hdr*)buf; if (buf_size < (ssize_t)sizeof(struct hci_command_hdr) || hdr->plen != buf_size - sizeof(struct hci_command_hdr)) exit(1); switch (hdr->opcode) { case HCI_OP_WRITE_SCAN_ENABLE: { uint8_t status = 0; hci_send_event_cmd_complete(fd, hdr->opcode, &status, sizeof(status)); return true; } case HCI_OP_READ_BD_ADDR: { struct hci_rp_read_bd_addr rp = {0}; rp.status = 0; memset(&rp.bdaddr, 0xaa, 6); hci_send_event_cmd_complete(fd, hdr->opcode, &rp, sizeof(rp)); return false; } case HCI_OP_READ_BUFFER_SIZE: { struct hci_rp_read_buffer_size rp = {0}; rp.status = 0; rp.acl_mtu = 1021; rp.sco_mtu = 96; rp.acl_max_pkt = 4; rp.sco_max_pkt = 6; hci_send_event_cmd_complete(fd, hdr->opcode, &rp, sizeof(rp)); return false; } } char dummy[0xf9] = {0}; hci_send_event_cmd_complete(fd, hdr->opcode, dummy, sizeof(dummy)); return false; } static void* event_thread(void* arg) { while (1) { char buf[1024] = {0}; ssize_t buf_size = read(vhci_fd, buf, sizeof(buf)); if (buf_size < 0) exit(1); if (buf_size > 0 && buf[0] == HCI_COMMAND_PKT) { if (process_command_pkt(vhci_fd, buf + 1, buf_size - 1)) break; } } return NULL; } #define HCI_HANDLE_1 200 #define HCI_HANDLE_2 201 #define HCI_PRIMARY 0 #define HCI_OP_RESET 0x0c03 static void initialize_vhci() { int hci_sock = socket(AF_BLUETOOTH, SOCK_RAW, BTPROTO_HCI); if (hci_sock < 0) exit(1); vhci_fd = open("/dev/vhci", O_RDWR); if (vhci_fd == -1) exit(1); const int kVhciFd = 202; if (dup2(vhci_fd, kVhciFd) < 0) exit(1); close(vhci_fd); vhci_fd = kVhciFd; struct vhci_vendor_pkt_request vendor_pkt_req = {HCI_VENDOR_PKT, HCI_PRIMARY}; if (write(vhci_fd, &vendor_pkt_req, sizeof(vendor_pkt_req)) != sizeof(vendor_pkt_req)) exit(1); struct vhci_pkt vhci_pkt; if (read(vhci_fd, &vhci_pkt, sizeof(vhci_pkt)) != sizeof(vhci_pkt)) exit(1); if (vhci_pkt.type == HCI_COMMAND_PKT && vhci_pkt.command_hdr.opcode == HCI_OP_RESET) { char response[1] = {0}; hci_send_event_cmd_complete(vhci_fd, HCI_OP_RESET, response, sizeof(response)); if (read(vhci_fd, &vhci_pkt, sizeof(vhci_pkt)) != sizeof(vhci_pkt)) exit(1); } if (vhci_pkt.type != HCI_VENDOR_PKT) exit(1); int dev_id = vhci_pkt.vendor_pkt.id; pthread_t th; if (pthread_create(&th, NULL, event_thread, NULL)) exit(1); int ret = ioctl(hci_sock, HCIDEVUP, dev_id); if (ret) { if (errno == ERFKILL) { rfkill_unblock_all(); ret = ioctl(hci_sock, HCIDEVUP, dev_id); } if (ret && errno != EALREADY) exit(1); } struct hci_dev_req dr = {0}; dr.dev_id = dev_id; dr.dev_opt = SCAN_PAGE; if (ioctl(hci_sock, HCISETSCAN, &dr)) exit(1); struct hci_ev_conn_request request; memset(&request, 0, sizeof(request)); memset(&request.bdaddr, 0xaa, 6); *(uint8_t*)&request.bdaddr.b[5] = 0x10; request.link_type = ACL_LINK; hci_send_event_packet(vhci_fd, HCI_EV_CONN_REQUEST, &request, sizeof(request)); struct hci_ev_conn_complete complete; memset(&complete, 0, sizeof(complete)); complete.status = 0; complete.handle = HCI_HANDLE_1; memset(&complete.bdaddr, 0xaa, 6); *(uint8_t*)&complete.bdaddr.b[5] = 0x10; complete.link_type = ACL_LINK; complete.encr_mode = 0; hci_send_event_packet(vhci_fd, HCI_EV_CONN_COMPLETE, &complete, sizeof(complete)); struct hci_ev_remote_features features; memset(&features, 0, sizeof(features)); features.status = 0; features.handle = HCI_HANDLE_1; hci_send_event_packet(vhci_fd, HCI_EV_REMOTE_FEATURES, &features, sizeof(features)); struct { struct hci_ev_le_meta le_meta; struct hci_ev_le_conn_complete le_conn; } le_conn; memset(&le_conn, 0, sizeof(le_conn)); le_conn.le_meta.subevent = HCI_EV_LE_CONN_COMPLETE; memset(&le_conn.le_conn.bdaddr, 0xaa, 6); *(uint8_t*)&le_conn.le_conn.bdaddr.b[5] = 0x11; le_conn.le_conn.role = 1; le_conn.le_conn.handle = HCI_HANDLE_2; hci_send_event_packet(vhci_fd, HCI_EV_LE_META, &le_conn, sizeof(le_conn)); pthread_join(th, NULL); close(hci_sock); } static long syz_genetlink_get_family_id(volatile long name, volatile long sock_arg) { int fd = sock_arg; if (fd < 0) { 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, false); if ((int)sock_arg < 0) close(fd); if (ret < 0) { return -1; } return ret; } static void setup_common() { if (mount(0, "/sys/fs/fuse/connections", "fusectl", 0, 0)) { } } static void setup_binderfs() { if (mkdir("/dev/binderfs", 0777)) { } if (mount("binder", "/dev/binderfs", "binder", 0, NULL)) { } } static void loop(); static void sandbox_common() { prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0); setsid(); int netns = open("/proc/self/ns/net", O_RDONLY); if (netns == -1) exit(1); if (dup2(netns, kInitNetNsFd) < 0) exit(1); close(netns); struct rlimit rlim; rlim.rlim_cur = rlim.rlim_max = (200 << 20); setrlimit(RLIMIT_AS, &rlim); rlim.rlim_cur = rlim.rlim_max = 32 << 20; setrlimit(RLIMIT_MEMLOCK, &rlim); rlim.rlim_cur = rlim.rlim_max = 136 << 20; setrlimit(RLIMIT_FSIZE, &rlim); rlim.rlim_cur = rlim.rlim_max = 1 << 20; setrlimit(RLIMIT_STACK, &rlim); rlim.rlim_cur = rlim.rlim_max = 128 << 20; setrlimit(RLIMIT_CORE, &rlim); rlim.rlim_cur = rlim.rlim_max = 256; setrlimit(RLIMIT_NOFILE, &rlim); if (unshare(CLONE_NEWNS)) { } if (mount(NULL, "/", NULL, MS_REC | MS_PRIVATE, NULL)) { } if (unshare(CLONE_NEWIPC)) { } if (unshare(0x02000000)) { } if (unshare(CLONE_NEWUTS)) { } if (unshare(CLONE_SYSVSEM)) { } typedef struct { const char* name; const char* value; } sysctl_t; static const sysctl_t sysctls[] = { {"/proc/sys/kernel/shmmax", "16777216"}, {"/proc/sys/kernel/shmall", "536870912"}, {"/proc/sys/kernel/shmmni", "1024"}, {"/proc/sys/kernel/msgmax", "8192"}, {"/proc/sys/kernel/msgmni", "1024"}, {"/proc/sys/kernel/msgmnb", "1024"}, {"/proc/sys/kernel/sem", "1024 1048576 500 1024"}, }; unsigned i; for (i = 0; i < sizeof(sysctls) / sizeof(sysctls[0]); i++) write_file(sysctls[i].name, sysctls[i].value); } static int wait_for_loop(int pid) { if (pid < 0) exit(1); int status = 0; while (waitpid(-1, &status, __WALL) != pid) { } return WEXITSTATUS(status); } static void drop_caps(void) { struct __user_cap_header_struct cap_hdr = {}; struct __user_cap_data_struct cap_data[2] = {}; cap_hdr.version = _LINUX_CAPABILITY_VERSION_3; cap_hdr.pid = getpid(); if (syscall(SYS_capget, &cap_hdr, &cap_data)) exit(1); const int drop = (1 << CAP_SYS_PTRACE) | (1 << CAP_SYS_NICE); cap_data[0].effective &= ~drop; cap_data[0].permitted &= ~drop; cap_data[0].inheritable &= ~drop; if (syscall(SYS_capset, &cap_hdr, &cap_data)) exit(1); } static int do_sandbox_none(void) { if (unshare(CLONE_NEWPID)) { } int pid = fork(); if (pid != 0) return wait_for_loop(pid); setup_common(); initialize_vhci(); sandbox_common(); drop_caps(); if (unshare(CLONE_NEWNET)) { } write_file("/proc/sys/net/ipv4/ping_group_range", "0 65535"); initialize_tun(); initialize_wifi_devices(); setup_binderfs(); loop(); exit(1); } static void close_fds() { for (int fd = 3; fd < MAX_FDS; fd++) close(fd); } static void setup_binfmt_misc() { if (mount(0, "/proc/sys/fs/binfmt_misc", "binfmt_misc", 0, 0)) { } write_file("/proc/sys/fs/binfmt_misc/register", ":syz0:M:0:\x01::./file0:"); write_file("/proc/sys/fs/binfmt_misc/register", ":syz1:M:1:\x02::./file0:POC"); } static void setup_usb() { if (chmod("/dev/raw-gadget", 0666)) exit(1); } static void setup_sysctl() { char mypid[32]; snprintf(mypid, sizeof(mypid), "%d", getpid()); struct { const char* name; const char* data; } files[] = { {"/sys/kernel/debug/x86/nmi_longest_ns", "10000000000"}, {"/proc/sys/kernel/hung_task_check_interval_secs", "20"}, {"/proc/sys/net/core/bpf_jit_kallsyms", "1"}, {"/proc/sys/net/core/bpf_jit_harden", "0"}, {"/proc/sys/kernel/kptr_restrict", "0"}, {"/proc/sys/kernel/softlockup_all_cpu_backtrace", "1"}, {"/proc/sys/fs/mount-max", "100"}, {"/proc/sys/vm/oom_dump_tasks", "0"}, {"/proc/sys/debug/exception-trace", "0"}, {"/proc/sys/kernel/printk", "7 4 1 3"}, {"/proc/sys/kernel/keys/gc_delay", "1"}, {"/proc/sys/vm/oom_kill_allocating_task", "1"}, {"/proc/sys/kernel/ctrl-alt-del", "0"}, {"/proc/sys/kernel/cad_pid", mypid}, }; for (size_t i = 0; i < sizeof(files) / sizeof(files[0]); i++) { if (!write_file(files[i].name, files[i].data)) printf("write to %s failed: %s\n", files[i].name, strerror(errno)); } } #define NL802154_CMD_SET_SHORT_ADDR 11 #define NL802154_ATTR_IFINDEX 3 #define NL802154_ATTR_SHORT_ADDR 10 static void setup_802154() { int sock_route = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE); if (sock_route == -1) exit(1); int sock_generic = socket(AF_NETLINK, SOCK_RAW, NETLINK_GENERIC); if (sock_generic < 0) exit(1); int nl802154_family_id = netlink_query_family_id(&nlmsg, sock_generic, "nl802154", true); for (int i = 0; i < 2; i++) { char devname[] = "wpan0"; devname[strlen(devname) - 1] += i; uint64_t hwaddr = 0xaaaaaaaaaaaa0002 + (i << 8); uint16_t shortaddr = 0xaaa0 + i; int ifindex = if_nametoindex(devname); struct genlmsghdr genlhdr; memset(&genlhdr, 0, sizeof(genlhdr)); genlhdr.cmd = NL802154_CMD_SET_SHORT_ADDR; netlink_init(&nlmsg, nl802154_family_id, 0, &genlhdr, sizeof(genlhdr)); netlink_attr(&nlmsg, NL802154_ATTR_IFINDEX, &ifindex, sizeof(ifindex)); netlink_attr(&nlmsg, NL802154_ATTR_SHORT_ADDR, &shortaddr, sizeof(shortaddr)); int err = netlink_send(&nlmsg, sock_generic); if (err < 0) { } netlink_device_change(&nlmsg, sock_route, devname, true, 0, &hwaddr, sizeof(hwaddr), 0); if (i == 0) { netlink_add_device_impl(&nlmsg, "lowpan", "lowpan0", false); netlink_done(&nlmsg); netlink_attr(&nlmsg, IFLA_LINK, &ifindex, sizeof(ifindex)); int err = netlink_send(&nlmsg, sock_route); if (err < 0) { } } } close(sock_route); close(sock_generic); } #define SWAP_FILE "./swap-file" #define SWAP_FILE_SIZE (128 * 1000 * 1000) static void setup_swap() { swapoff(SWAP_FILE); unlink(SWAP_FILE); int fd = open(SWAP_FILE, O_CREAT | O_WRONLY | O_CLOEXEC, 0600); if (fd == -1) { exit(1); return; } fallocate(fd, FALLOC_FL_ZERO_RANGE, 0, SWAP_FILE_SIZE); close(fd); char cmdline[64]; sprintf(cmdline, "mkswap %s", SWAP_FILE); if (runcmdline(cmdline)) { exit(1); return; } if (swapon(SWAP_FILE, SWAP_FLAG_PREFER) == 1) { exit(1); return; } } 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 < 9; 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); close_fds(); } uint64_t r[4] = {0xffffffffffffffff, 0x0, 0xffffffffffffffff, 0x0}; void execute_call(int call) { intptr_t res = 0; switch (call) { case 0: memcpy((void*)0x20000080, "/dev/virtual_nci\000", 17); res = syscall(__NR_openat, /*fd=*/0xffffffffffffff9cul, /*file=*/0x20000080ul, /*flags=*/2ul, /*mode=*/0ul); if (res != -1) r[0] = res; break; case 1: res = syscall(__NR_ioctl, /*fd=*/r[0], /*cmd=*/0, /*arg=*/0x200000c0ul); if (res != -1) r[1] = *(uint32_t*)0x200000c0; break; case 2: res = -1; res = syz_init_net_socket(/*domain=*/0x10, /*type=*/3, /*proto=*/0x10); if (res != -1) r[2] = res; break; case 3: memcpy((void*)0x20000100, "nfc\000", 4); res = -1; res = syz_genetlink_get_family_id(/*name=*/0x20000100, /*fd=*/r[2]); if (res != -1) r[3] = res; break; case 4: *(uint64_t*)0x20000140 = 0; *(uint32_t*)0x20000148 = 0; *(uint64_t*)0x20000150 = 0x20000180; *(uint64_t*)0x20000180 = 0x200001c0; *(uint32_t*)0x200001c0 = 0x1c; *(uint16_t*)0x200001c4 = r[3]; *(uint16_t*)0x200001c6 = 1; *(uint32_t*)0x200001c8 = 0x123; *(uint32_t*)0x200001cc = 0x234; *(uint8_t*)0x200001d0 = 2; *(uint8_t*)0x200001d1 = 0; *(uint16_t*)0x200001d2 = 0; *(uint16_t*)0x200001d4 = 8; *(uint16_t*)0x200001d6 = 1; *(uint32_t*)0x200001d8 = r[1]; *(uint64_t*)0x20000188 = 0x1c; *(uint64_t*)0x20000158 = 1; *(uint64_t*)0x20000160 = 0; *(uint64_t*)0x20000168 = 0; *(uint32_t*)0x20000170 = 0; syscall(__NR_sendmsg, /*fd=*/r[2], /*msg=*/0x20000140ul, /*f=*/0ul); break; case 5: STORE_BY_BITMASK(uint8_t, , 0x20000280, 0, 0, 4); STORE_BY_BITMASK(uint8_t, , 0x20000280, 0, 4, 1); STORE_BY_BITMASK(uint8_t, , 0x20000280, 2, 5, 3); *(uint8_t*)0x20000281 = 0; *(uint8_t*)0x20000282 = 0; *(uint8_t*)0x20000283 = 0; *(uint8_t*)0x20000284 = 0; *(uint8_t*)0x20000285 = 0; syscall(__NR_write, /*fd=*/r[0], /*data=*/0x20000280ul, /*len=*/6ul); break; case 6: STORE_BY_BITMASK(uint8_t, , 0x20000340, 0, 0, 4); STORE_BY_BITMASK(uint8_t, , 0x20000340, 0, 4, 1); STORE_BY_BITMASK(uint8_t, , 0x20000340, 2, 5, 3); *(uint8_t*)0x20000341 = 1; *(uint8_t*)0x20000342 = 0; *(uint8_t*)0x20000343 = 0; *(uint32_t*)0x20000344 = 0; *(uint8_t*)0x20000348 = 0; *(uint8_t*)0x20000349 = 0; *(uint16_t*)0x2000034a = 0; *(uint8_t*)0x2000034c = 0; *(uint16_t*)0x2000034d = 0; *(uint8_t*)0x2000034f = 0; *(uint32_t*)0x20000350 = 0; syscall(__NR_write, /*fd=*/r[0], /*data=*/0x20000340ul, /*len=*/0x14ul); break; case 7: STORE_BY_BITMASK(uint8_t, , 0x20000400, 1, 0, 4); STORE_BY_BITMASK(uint8_t, , 0x20000400, 0, 4, 1); STORE_BY_BITMASK(uint8_t, , 0x20000400, 2, 5, 3); *(uint8_t*)0x20000401 = 0; *(uint8_t*)0x20000402 = 0; *(uint8_t*)0x20000403 = 0; syscall(__NR_write, /*fd=*/r[0], /*data=*/0x20000400ul, /*len=*/4ul); break; case 8: *(uint64_t*)0x20000440 = 0; *(uint32_t*)0x20000448 = 0; *(uint64_t*)0x20000450 = 0x20000480; *(uint64_t*)0x20000480 = 0x200004c0; *(uint32_t*)0x200004c0 = 0x24; *(uint16_t*)0x200004c4 = r[3]; *(uint16_t*)0x200004c6 = 1; *(uint32_t*)0x200004c8 = 0x123; *(uint32_t*)0x200004cc = 0x234; *(uint8_t*)0x200004d0 = 6; *(uint8_t*)0x200004d1 = 0; *(uint16_t*)0x200004d2 = 0; *(uint16_t*)0x200004d4 = 8; *(uint16_t*)0x200004d6 = 1; *(uint32_t*)0x200004d8 = r[1]; *(uint16_t*)0x200004dc = 8; *(uint16_t*)0x200004de = 3; *(uint32_t*)0x200004e0 = -1; *(uint64_t*)0x20000488 = 0x24; *(uint64_t*)0x20000458 = 1; *(uint64_t*)0x20000460 = 0; *(uint64_t*)0x20000468 = 0; *(uint32_t*)0x20000470 = 0; syscall(__NR_sendmsg, /*fd=*/r[2], /*msg=*/0x20000440ul, /*f=*/0ul); break; } } int main(void) { syscall(__NR_mmap, /*addr=*/0x1ffff000ul, /*len=*/0x1000ul, /*prot=*/0ul, /*flags=*/0x32ul, /*fd=*/-1, /*offset=*/0ul); syscall(__NR_mmap, /*addr=*/0x20000000ul, /*len=*/0x1000000ul, /*prot=*/7ul, /*flags=*/0x32ul, /*fd=*/-1, /*offset=*/0ul); syscall(__NR_mmap, /*addr=*/0x21000000ul, /*len=*/0x1000ul, /*prot=*/0ul, /*flags=*/0x32ul, /*fd=*/-1, /*offset=*/0ul); setup_sysctl(); setup_binfmt_misc(); setup_usb(); setup_802154(); setup_swap(); use_temporary_dir(); do_sandbox_none(); return 0; }