// https://syzkaller.appspot.com/bug?id=788ed2c7e973b69fd551ba6b5e21848dba2c1670 // 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 static unsigned long long procid; static __thread int skip_segv; static __thread jmp_buf segv_env; static void segv_handler(int sig, siginfo_t* info, void* ctx) { uintptr_t addr = (uintptr_t)info->si_addr; const uintptr_t prog_start = 1 << 20; const uintptr_t prog_end = 100 << 20; int skip = __atomic_load_n(&skip_segv, __ATOMIC_RELAXED) != 0; int valid = addr < prog_start || addr > prog_end; if (skip && valid) { _longjmp(segv_env, 1); } exit(sig); } static void install_segv_handler(void) { struct sigaction sa; memset(&sa, 0, sizeof(sa)); sa.sa_handler = SIG_IGN; syscall(SYS_rt_sigaction, 0x20, &sa, NULL, 8); syscall(SYS_rt_sigaction, 0x21, &sa, NULL, 8); memset(&sa, 0, sizeof(sa)); sa.sa_sigaction = segv_handler; sa.sa_flags = SA_NODEFER | SA_SIGINFO; sigaction(SIGSEGV, &sa, NULL); sigaction(SIGBUS, &sa, NULL); } #define NONFAILING(...) \ ({ \ int ok = 1; \ __atomic_fetch_add(&skip_segv, 1, __ATOMIC_SEQ_CST); \ if (_setjmp(segv_env) == 0) { \ __VA_ARGS__; \ } else \ ok = 0; \ __atomic_fetch_sub(&skip_segv, 1, __ATOMIC_SEQ_CST); \ ok; \ }) 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); } 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) { 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; unsigned n = sendto(sock, nlmsg->buf, hdr->nlmsg_len, 0, (struct sockaddr*)&addr, sizeof(addr)); if (n != hdr->nlmsg_len) exit(1); n = recv(sock, nlmsg->buf, sizeof(nlmsg->buf), 0); if (reply_len) *reply_len = 0; if (hdr->nlmsg_type == NLMSG_DONE) return 0; if (n < sizeof(struct nlmsghdr)) exit(1); if (reply_len && hdr->nlmsg_type == reply_type) { *reply_len = n; return 0; } if (n < sizeof(struct nlmsghdr) + sizeof(struct nlmsgerr)) exit(1); if (hdr->nlmsg_type != NLMSG_ERROR) exit(1); return ((struct nlmsgerr*)(hdr + 1))->error; } static int netlink_send(struct nlmsg* nlmsg, int sock) { return netlink_send_ext(nlmsg, sock, 0, NULL); } static int netlink_query_family_id(struct nlmsg* nlmsg, int sock, const char* family_name) { 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); 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) { return -1; } recv(sock, nlmsg->buf, sizeof(nlmsg->buf), 0); return id; } static int netlink_next_msg(struct nlmsg* nlmsg, unsigned int offset, unsigned int total_len) { struct nlmsghdr* hdr = (struct nlmsghdr*)(nlmsg->buf + offset); if (offset == total_len || offset + hdr->nlmsg_len > total_len) return -1; return hdr->nlmsg_len; } static void netlink_add_device_impl(struct nlmsg* nlmsg, const char* type, const char* name) { struct ifinfomsg hdr; memset(&hdr, 0, sizeof(hdr)); 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_add_device(struct nlmsg* nlmsg, int sock, const char* type, const char* name) { netlink_add_device_impl(nlmsg, type, name); netlink_done(nlmsg); int err = netlink_send(nlmsg, sock); (void)err; } static void netlink_add_veth(struct nlmsg* nlmsg, int sock, const char* name, const char* peer) { netlink_add_device_impl(nlmsg, "veth", name); netlink_nest(nlmsg, IFLA_INFO_DATA); netlink_nest(nlmsg, VETH_INFO_PEER); nlmsg->pos += sizeof(struct ifinfomsg); netlink_attr(nlmsg, IFLA_IFNAME, peer, strlen(peer)); netlink_done(nlmsg); netlink_done(nlmsg); netlink_done(nlmsg); int err = netlink_send(nlmsg, sock); (void)err; } static void netlink_add_hsr(struct nlmsg* nlmsg, int sock, const char* name, const char* slave1, const char* slave2) { netlink_add_device_impl(nlmsg, "hsr", name); netlink_nest(nlmsg, IFLA_INFO_DATA); int ifindex1 = if_nametoindex(slave1); netlink_attr(nlmsg, IFLA_HSR_SLAVE1, &ifindex1, sizeof(ifindex1)); int ifindex2 = if_nametoindex(slave2); netlink_attr(nlmsg, IFLA_HSR_SLAVE2, &ifindex2, sizeof(ifindex2)); netlink_done(nlmsg); netlink_done(nlmsg); int err = netlink_send(nlmsg, sock); (void)err; } static void netlink_add_linked(struct nlmsg* nlmsg, int sock, const char* type, const char* name, const char* link) { netlink_add_device_impl(nlmsg, type, name); netlink_done(nlmsg); int ifindex = if_nametoindex(link); netlink_attr(nlmsg, IFLA_LINK, &ifindex, sizeof(ifindex)); int err = netlink_send(nlmsg, sock); (void)err; } static void netlink_add_vlan(struct nlmsg* nlmsg, int sock, const char* name, const char* link, uint16_t id, uint16_t proto) { netlink_add_device_impl(nlmsg, "vlan", name); netlink_nest(nlmsg, IFLA_INFO_DATA); netlink_attr(nlmsg, IFLA_VLAN_ID, &id, sizeof(id)); netlink_attr(nlmsg, IFLA_VLAN_PROTOCOL, &proto, sizeof(proto)); netlink_done(nlmsg); netlink_done(nlmsg); int ifindex = if_nametoindex(link); netlink_attr(nlmsg, IFLA_LINK, &ifindex, sizeof(ifindex)); int err = netlink_send(nlmsg, sock); (void)err; } static void netlink_add_macvlan(struct nlmsg* nlmsg, int sock, const char* name, const char* link) { netlink_add_device_impl(nlmsg, "macvlan", name); netlink_nest(nlmsg, IFLA_INFO_DATA); uint32_t mode = MACVLAN_MODE_BRIDGE; netlink_attr(nlmsg, IFLA_MACVLAN_MODE, &mode, sizeof(mode)); netlink_done(nlmsg); netlink_done(nlmsg); int ifindex = if_nametoindex(link); netlink_attr(nlmsg, IFLA_LINK, &ifindex, sizeof(ifindex)); int err = netlink_send(nlmsg, sock); (void)err; } static void netlink_add_geneve(struct nlmsg* nlmsg, int sock, const char* name, uint32_t vni, struct in_addr* addr4, struct in6_addr* addr6) { netlink_add_device_impl(nlmsg, "geneve", name); netlink_nest(nlmsg, IFLA_INFO_DATA); netlink_attr(nlmsg, IFLA_GENEVE_ID, &vni, sizeof(vni)); if (addr4) netlink_attr(nlmsg, IFLA_GENEVE_REMOTE, addr4, sizeof(*addr4)); if (addr6) netlink_attr(nlmsg, IFLA_GENEVE_REMOTE6, addr6, sizeof(*addr6)); netlink_done(nlmsg); netlink_done(nlmsg); int err = netlink_send(nlmsg, sock); (void)err; } #define IFLA_IPVLAN_FLAGS 2 #define IPVLAN_MODE_L3S 2 #undef IPVLAN_F_VEPA #define IPVLAN_F_VEPA 2 static void netlink_add_ipvlan(struct nlmsg* nlmsg, int sock, const char* name, const char* link, uint16_t mode, uint16_t flags) { netlink_add_device_impl(nlmsg, "ipvlan", name); netlink_nest(nlmsg, IFLA_INFO_DATA); netlink_attr(nlmsg, IFLA_IPVLAN_MODE, &mode, sizeof(mode)); netlink_attr(nlmsg, IFLA_IPVLAN_FLAGS, &flags, sizeof(flags)); netlink_done(nlmsg); netlink_done(nlmsg); int ifindex = if_nametoindex(link); netlink_attr(nlmsg, IFLA_LINK, &ifindex, sizeof(ifindex)); int err = netlink_send(nlmsg, sock); (void)err; } 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); (void)err; } 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)); (void)err; } 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)); (void)err; } 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); (void)err; } 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 = 240; 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); } #define DEVLINK_FAMILY_NAME "devlink" #define DEVLINK_CMD_PORT_GET 5 #define DEVLINK_ATTR_BUS_NAME 1 #define DEVLINK_ATTR_DEV_NAME 2 #define DEVLINK_ATTR_NETDEV_NAME 7 static struct nlmsg nlmsg2; static void initialize_devlink_ports(const char* bus_name, const char* dev_name, const char* netdev_prefix) { struct genlmsghdr genlhdr; int len, total_len, id, err, offset; uint16_t netdev_index; int sock = socket(AF_NETLINK, SOCK_RAW, NETLINK_GENERIC); if (sock == -1) exit(1); int rtsock = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE); if (rtsock == -1) exit(1); id = netlink_query_family_id(&nlmsg, sock, DEVLINK_FAMILY_NAME); if (id == -1) goto error; memset(&genlhdr, 0, sizeof(genlhdr)); genlhdr.cmd = DEVLINK_CMD_PORT_GET; netlink_init(&nlmsg, id, NLM_F_DUMP, &genlhdr, sizeof(genlhdr)); netlink_attr(&nlmsg, DEVLINK_ATTR_BUS_NAME, bus_name, strlen(bus_name) + 1); netlink_attr(&nlmsg, DEVLINK_ATTR_DEV_NAME, dev_name, strlen(dev_name) + 1); err = netlink_send_ext(&nlmsg, sock, id, &total_len); if (err < 0) { goto error; } offset = 0; netdev_index = 0; while ((len = netlink_next_msg(&nlmsg, offset, total_len)) != -1) { struct nlattr* attr = (struct nlattr*)(nlmsg.buf + offset + NLMSG_HDRLEN + NLMSG_ALIGN(sizeof(genlhdr))); for (; (char*)attr < nlmsg.buf + offset + len; attr = (struct nlattr*)((char*)attr + NLMSG_ALIGN(attr->nla_len))) { if (attr->nla_type == DEVLINK_ATTR_NETDEV_NAME) { char* port_name; char netdev_name[IFNAMSIZ]; port_name = (char*)(attr + 1); snprintf(netdev_name, sizeof(netdev_name), "%s%d", netdev_prefix, netdev_index); netlink_device_change(&nlmsg2, rtsock, port_name, true, 0, 0, 0, netdev_name); break; } } offset += len; netdev_index++; } error: close(rtsock); close(sock); } #define DEV_IPV4 "172.20.20.%d" #define DEV_IPV6 "fe80::%02x" #define DEV_MAC 0x00aaaaaaaaaa static void netdevsim_add(unsigned int addr, unsigned int port_count) { char buf[16]; sprintf(buf, "%u %u", addr, port_count); if (write_file("/sys/bus/netdevsim/new_device", buf)) { snprintf(buf, sizeof(buf), "netdevsim%d", addr); initialize_devlink_ports("netdevsim", buf, "netdevsim"); } } #define WG_GENL_NAME "wireguard" enum wg_cmd { WG_CMD_GET_DEVICE, WG_CMD_SET_DEVICE, }; enum wgdevice_attribute { WGDEVICE_A_UNSPEC, WGDEVICE_A_IFINDEX, WGDEVICE_A_IFNAME, WGDEVICE_A_PRIVATE_KEY, WGDEVICE_A_PUBLIC_KEY, WGDEVICE_A_FLAGS, WGDEVICE_A_LISTEN_PORT, WGDEVICE_A_FWMARK, WGDEVICE_A_PEERS, }; enum wgpeer_attribute { WGPEER_A_UNSPEC, WGPEER_A_PUBLIC_KEY, WGPEER_A_PRESHARED_KEY, WGPEER_A_FLAGS, WGPEER_A_ENDPOINT, WGPEER_A_PERSISTENT_KEEPALIVE_INTERVAL, WGPEER_A_LAST_HANDSHAKE_TIME, WGPEER_A_RX_BYTES, WGPEER_A_TX_BYTES, WGPEER_A_ALLOWEDIPS, WGPEER_A_PROTOCOL_VERSION, }; enum wgallowedip_attribute { WGALLOWEDIP_A_UNSPEC, WGALLOWEDIP_A_FAMILY, WGALLOWEDIP_A_IPADDR, WGALLOWEDIP_A_CIDR_MASK, }; static void netlink_wireguard_setup(void) { const char ifname_a[] = "wg0"; const char ifname_b[] = "wg1"; const char ifname_c[] = "wg2"; const char private_a[] = "\xa0\x5c\xa8\x4f\x6c\x9c\x8e\x38\x53\xe2\xfd\x7a" "\x70\xae\x0f\xb2\x0f\xa1\x52\x60\x0c\xb0\x08\x45" "\x17\x4f\x08\x07\x6f\x8d\x78\x43"; const char private_b[] = "\xb0\x80\x73\xe8\xd4\x4e\x91\xe3\xda\x92\x2c\x22" "\x43\x82\x44\xbb\x88\x5c\x69\xe2\x69\xc8\xe9\xd8" "\x35\xb1\x14\x29\x3a\x4d\xdc\x6e"; const char private_c[] = "\xa0\xcb\x87\x9a\x47\xf5\xbc\x64\x4c\x0e\x69\x3f" "\xa6\xd0\x31\xc7\x4a\x15\x53\xb6\xe9\x01\xb9\xff" "\x2f\x51\x8c\x78\x04\x2f\xb5\x42"; const char public_a[] = "\x97\x5c\x9d\x81\xc9\x83\xc8\x20\x9e\xe7\x81\x25\x4b" "\x89\x9f\x8e\xd9\x25\xae\x9f\x09\x23\xc2\x3c\x62\xf5" "\x3c\x57\xcd\xbf\x69\x1c"; const char public_b[] = "\xd1\x73\x28\x99\xf6\x11\xcd\x89\x94\x03\x4d\x7f\x41" "\x3d\xc9\x57\x63\x0e\x54\x93\xc2\x85\xac\xa4\x00\x65" "\xcb\x63\x11\xbe\x69\x6b"; const char public_c[] = "\xf4\x4d\xa3\x67\xa8\x8e\xe6\x56\x4f\x02\x02\x11\x45" "\x67\x27\x08\x2f\x5c\xeb\xee\x8b\x1b\xf5\xeb\x73\x37" "\x34\x1b\x45\x9b\x39\x22"; const uint16_t listen_a = 20001; const uint16_t listen_b = 20002; const uint16_t listen_c = 20003; const uint16_t af_inet = AF_INET; const uint16_t af_inet6 = AF_INET6; const struct sockaddr_in endpoint_b_v4 = { .sin_family = AF_INET, .sin_port = htons(listen_b), .sin_addr = {htonl(INADDR_LOOPBACK)}}; const struct sockaddr_in endpoint_c_v4 = { .sin_family = AF_INET, .sin_port = htons(listen_c), .sin_addr = {htonl(INADDR_LOOPBACK)}}; struct sockaddr_in6 endpoint_a_v6 = {.sin6_family = AF_INET6, .sin6_port = htons(listen_a)}; endpoint_a_v6.sin6_addr = in6addr_loopback; struct sockaddr_in6 endpoint_c_v6 = {.sin6_family = AF_INET6, .sin6_port = htons(listen_c)}; endpoint_c_v6.sin6_addr = in6addr_loopback; const struct in_addr first_half_v4 = {0}; const struct in_addr second_half_v4 = {(uint32_t)htonl(128 << 24)}; const struct in6_addr first_half_v6 = {{{0}}}; const struct in6_addr second_half_v6 = {{{0x80}}}; const uint8_t half_cidr = 1; const uint16_t persistent_keepalives[] = {1, 3, 7, 9, 14, 19}; struct genlmsghdr genlhdr = {.cmd = WG_CMD_SET_DEVICE, .version = 1}; int sock; int id, err; sock = socket(AF_NETLINK, SOCK_RAW, NETLINK_GENERIC); if (sock == -1) { return; } id = netlink_query_family_id(&nlmsg, sock, WG_GENL_NAME); if (id == -1) goto error; netlink_init(&nlmsg, id, 0, &genlhdr, sizeof(genlhdr)); netlink_attr(&nlmsg, WGDEVICE_A_IFNAME, ifname_a, strlen(ifname_a) + 1); netlink_attr(&nlmsg, WGDEVICE_A_PRIVATE_KEY, private_a, 32); netlink_attr(&nlmsg, WGDEVICE_A_LISTEN_PORT, &listen_a, 2); netlink_nest(&nlmsg, NLA_F_NESTED | WGDEVICE_A_PEERS); netlink_nest(&nlmsg, NLA_F_NESTED | 0); netlink_attr(&nlmsg, WGPEER_A_PUBLIC_KEY, public_b, 32); netlink_attr(&nlmsg, WGPEER_A_ENDPOINT, &endpoint_b_v4, sizeof(endpoint_b_v4)); netlink_attr(&nlmsg, WGPEER_A_PERSISTENT_KEEPALIVE_INTERVAL, &persistent_keepalives[0], 2); netlink_nest(&nlmsg, NLA_F_NESTED | WGPEER_A_ALLOWEDIPS); netlink_nest(&nlmsg, NLA_F_NESTED | 0); netlink_attr(&nlmsg, WGALLOWEDIP_A_FAMILY, &af_inet, 2); netlink_attr(&nlmsg, WGALLOWEDIP_A_IPADDR, &first_half_v4, sizeof(first_half_v4)); netlink_attr(&nlmsg, WGALLOWEDIP_A_CIDR_MASK, &half_cidr, 1); netlink_done(&nlmsg); netlink_nest(&nlmsg, NLA_F_NESTED | 0); netlink_attr(&nlmsg, WGALLOWEDIP_A_FAMILY, &af_inet6, 2); netlink_attr(&nlmsg, WGALLOWEDIP_A_IPADDR, &first_half_v6, sizeof(first_half_v6)); netlink_attr(&nlmsg, WGALLOWEDIP_A_CIDR_MASK, &half_cidr, 1); netlink_done(&nlmsg); netlink_done(&nlmsg); netlink_done(&nlmsg); netlink_nest(&nlmsg, NLA_F_NESTED | 0); netlink_attr(&nlmsg, WGPEER_A_PUBLIC_KEY, public_c, 32); netlink_attr(&nlmsg, WGPEER_A_ENDPOINT, &endpoint_c_v6, sizeof(endpoint_c_v6)); netlink_attr(&nlmsg, WGPEER_A_PERSISTENT_KEEPALIVE_INTERVAL, &persistent_keepalives[1], 2); netlink_nest(&nlmsg, NLA_F_NESTED | WGPEER_A_ALLOWEDIPS); netlink_nest(&nlmsg, NLA_F_NESTED | 0); netlink_attr(&nlmsg, WGALLOWEDIP_A_FAMILY, &af_inet, 2); netlink_attr(&nlmsg, WGALLOWEDIP_A_IPADDR, &second_half_v4, sizeof(second_half_v4)); netlink_attr(&nlmsg, WGALLOWEDIP_A_CIDR_MASK, &half_cidr, 1); netlink_done(&nlmsg); netlink_nest(&nlmsg, NLA_F_NESTED | 0); netlink_attr(&nlmsg, WGALLOWEDIP_A_FAMILY, &af_inet6, 2); netlink_attr(&nlmsg, WGALLOWEDIP_A_IPADDR, &second_half_v6, sizeof(second_half_v6)); netlink_attr(&nlmsg, WGALLOWEDIP_A_CIDR_MASK, &half_cidr, 1); netlink_done(&nlmsg); netlink_done(&nlmsg); netlink_done(&nlmsg); netlink_done(&nlmsg); err = netlink_send(&nlmsg, sock); if (err < 0) { } netlink_init(&nlmsg, id, 0, &genlhdr, sizeof(genlhdr)); netlink_attr(&nlmsg, WGDEVICE_A_IFNAME, ifname_b, strlen(ifname_b) + 1); netlink_attr(&nlmsg, WGDEVICE_A_PRIVATE_KEY, private_b, 32); netlink_attr(&nlmsg, WGDEVICE_A_LISTEN_PORT, &listen_b, 2); netlink_nest(&nlmsg, NLA_F_NESTED | WGDEVICE_A_PEERS); netlink_nest(&nlmsg, NLA_F_NESTED | 0); netlink_attr(&nlmsg, WGPEER_A_PUBLIC_KEY, public_a, 32); netlink_attr(&nlmsg, WGPEER_A_ENDPOINT, &endpoint_a_v6, sizeof(endpoint_a_v6)); netlink_attr(&nlmsg, WGPEER_A_PERSISTENT_KEEPALIVE_INTERVAL, &persistent_keepalives[2], 2); netlink_nest(&nlmsg, NLA_F_NESTED | WGPEER_A_ALLOWEDIPS); netlink_nest(&nlmsg, NLA_F_NESTED | 0); netlink_attr(&nlmsg, WGALLOWEDIP_A_FAMILY, &af_inet, 2); netlink_attr(&nlmsg, WGALLOWEDIP_A_IPADDR, &first_half_v4, sizeof(first_half_v4)); netlink_attr(&nlmsg, WGALLOWEDIP_A_CIDR_MASK, &half_cidr, 1); netlink_done(&nlmsg); netlink_nest(&nlmsg, NLA_F_NESTED | 0); netlink_attr(&nlmsg, WGALLOWEDIP_A_FAMILY, &af_inet6, 2); netlink_attr(&nlmsg, WGALLOWEDIP_A_IPADDR, &first_half_v6, sizeof(first_half_v6)); netlink_attr(&nlmsg, WGALLOWEDIP_A_CIDR_MASK, &half_cidr, 1); netlink_done(&nlmsg); netlink_done(&nlmsg); netlink_done(&nlmsg); netlink_nest(&nlmsg, NLA_F_NESTED | 0); netlink_attr(&nlmsg, WGPEER_A_PUBLIC_KEY, public_c, 32); netlink_attr(&nlmsg, WGPEER_A_ENDPOINT, &endpoint_c_v4, sizeof(endpoint_c_v4)); netlink_attr(&nlmsg, WGPEER_A_PERSISTENT_KEEPALIVE_INTERVAL, &persistent_keepalives[3], 2); netlink_nest(&nlmsg, NLA_F_NESTED | WGPEER_A_ALLOWEDIPS); netlink_nest(&nlmsg, NLA_F_NESTED | 0); netlink_attr(&nlmsg, WGALLOWEDIP_A_FAMILY, &af_inet, 2); netlink_attr(&nlmsg, WGALLOWEDIP_A_IPADDR, &second_half_v4, sizeof(second_half_v4)); netlink_attr(&nlmsg, WGALLOWEDIP_A_CIDR_MASK, &half_cidr, 1); netlink_done(&nlmsg); netlink_nest(&nlmsg, NLA_F_NESTED | 0); netlink_attr(&nlmsg, WGALLOWEDIP_A_FAMILY, &af_inet6, 2); netlink_attr(&nlmsg, WGALLOWEDIP_A_IPADDR, &second_half_v6, sizeof(second_half_v6)); netlink_attr(&nlmsg, WGALLOWEDIP_A_CIDR_MASK, &half_cidr, 1); netlink_done(&nlmsg); netlink_done(&nlmsg); netlink_done(&nlmsg); netlink_done(&nlmsg); err = netlink_send(&nlmsg, sock); if (err < 0) { } netlink_init(&nlmsg, id, 0, &genlhdr, sizeof(genlhdr)); netlink_attr(&nlmsg, WGDEVICE_A_IFNAME, ifname_c, strlen(ifname_c) + 1); netlink_attr(&nlmsg, WGDEVICE_A_PRIVATE_KEY, private_c, 32); netlink_attr(&nlmsg, WGDEVICE_A_LISTEN_PORT, &listen_c, 2); netlink_nest(&nlmsg, NLA_F_NESTED | WGDEVICE_A_PEERS); netlink_nest(&nlmsg, NLA_F_NESTED | 0); netlink_attr(&nlmsg, WGPEER_A_PUBLIC_KEY, public_a, 32); netlink_attr(&nlmsg, WGPEER_A_ENDPOINT, &endpoint_a_v6, sizeof(endpoint_a_v6)); netlink_attr(&nlmsg, WGPEER_A_PERSISTENT_KEEPALIVE_INTERVAL, &persistent_keepalives[4], 2); netlink_nest(&nlmsg, NLA_F_NESTED | WGPEER_A_ALLOWEDIPS); netlink_nest(&nlmsg, NLA_F_NESTED | 0); netlink_attr(&nlmsg, WGALLOWEDIP_A_FAMILY, &af_inet, 2); netlink_attr(&nlmsg, WGALLOWEDIP_A_IPADDR, &first_half_v4, sizeof(first_half_v4)); netlink_attr(&nlmsg, WGALLOWEDIP_A_CIDR_MASK, &half_cidr, 1); netlink_done(&nlmsg); netlink_nest(&nlmsg, NLA_F_NESTED | 0); netlink_attr(&nlmsg, WGALLOWEDIP_A_FAMILY, &af_inet6, 2); netlink_attr(&nlmsg, WGALLOWEDIP_A_IPADDR, &first_half_v6, sizeof(first_half_v6)); netlink_attr(&nlmsg, WGALLOWEDIP_A_CIDR_MASK, &half_cidr, 1); netlink_done(&nlmsg); netlink_done(&nlmsg); netlink_done(&nlmsg); netlink_nest(&nlmsg, NLA_F_NESTED | 0); netlink_attr(&nlmsg, WGPEER_A_PUBLIC_KEY, public_b, 32); netlink_attr(&nlmsg, WGPEER_A_ENDPOINT, &endpoint_b_v4, sizeof(endpoint_b_v4)); netlink_attr(&nlmsg, WGPEER_A_PERSISTENT_KEEPALIVE_INTERVAL, &persistent_keepalives[5], 2); netlink_nest(&nlmsg, NLA_F_NESTED | WGPEER_A_ALLOWEDIPS); netlink_nest(&nlmsg, NLA_F_NESTED | 0); netlink_attr(&nlmsg, WGALLOWEDIP_A_FAMILY, &af_inet, 2); netlink_attr(&nlmsg, WGALLOWEDIP_A_IPADDR, &second_half_v4, sizeof(second_half_v4)); netlink_attr(&nlmsg, WGALLOWEDIP_A_CIDR_MASK, &half_cidr, 1); netlink_done(&nlmsg); netlink_nest(&nlmsg, NLA_F_NESTED | 0); netlink_attr(&nlmsg, WGALLOWEDIP_A_FAMILY, &af_inet6, 2); netlink_attr(&nlmsg, WGALLOWEDIP_A_IPADDR, &second_half_v6, sizeof(second_half_v6)); netlink_attr(&nlmsg, WGALLOWEDIP_A_CIDR_MASK, &half_cidr, 1); netlink_done(&nlmsg); netlink_done(&nlmsg); netlink_done(&nlmsg); netlink_done(&nlmsg); err = netlink_send(&nlmsg, sock); if (err < 0) { } error: close(sock); } static void initialize_netdevices(void) { char netdevsim[16]; sprintf(netdevsim, "netdevsim%d", (int)procid); struct { const char* type; const char* dev; } devtypes[] = { {"ip6gretap", "ip6gretap0"}, {"bridge", "bridge0"}, {"vcan", "vcan0"}, {"bond", "bond0"}, {"team", "team0"}, {"dummy", "dummy0"}, {"nlmon", "nlmon0"}, {"caif", "caif0"}, {"batadv", "batadv0"}, {"vxcan", "vxcan1"}, {"netdevsim", netdevsim}, {"veth", 0}, {"xfrm", "xfrm0"}, {"wireguard", "wg0"}, {"wireguard", "wg1"}, {"wireguard", "wg2"}, }; const char* devmasters[] = {"bridge", "bond", "team", "batadv"}; struct { const char* name; int macsize; bool noipv6; } devices[] = { {"lo", ETH_ALEN}, {"sit0", 0}, {"bridge0", ETH_ALEN}, {"vcan0", 0, true}, {"tunl0", 0}, {"gre0", 0}, {"gretap0", ETH_ALEN}, {"ip_vti0", 0}, {"ip6_vti0", 0}, {"ip6tnl0", 0}, {"ip6gre0", 0}, {"ip6gretap0", ETH_ALEN}, {"erspan0", ETH_ALEN}, {"bond0", ETH_ALEN}, {"veth0", ETH_ALEN}, {"veth1", ETH_ALEN}, {"team0", ETH_ALEN}, {"veth0_to_bridge", ETH_ALEN}, {"veth1_to_bridge", ETH_ALEN}, {"veth0_to_bond", ETH_ALEN}, {"veth1_to_bond", ETH_ALEN}, {"veth0_to_team", ETH_ALEN}, {"veth1_to_team", ETH_ALEN}, {"veth0_to_hsr", ETH_ALEN}, {"veth1_to_hsr", ETH_ALEN}, {"hsr0", 0}, {"dummy0", ETH_ALEN}, {"nlmon0", 0}, {"vxcan0", 0, true}, {"vxcan1", 0, true}, {"caif0", ETH_ALEN}, {"batadv0", ETH_ALEN}, {netdevsim, ETH_ALEN}, {"xfrm0", ETH_ALEN}, {"veth0_virt_wifi", ETH_ALEN}, {"veth1_virt_wifi", ETH_ALEN}, {"virt_wifi0", ETH_ALEN}, {"veth0_vlan", ETH_ALEN}, {"veth1_vlan", ETH_ALEN}, {"vlan0", ETH_ALEN}, {"vlan1", ETH_ALEN}, {"macvlan0", ETH_ALEN}, {"macvlan1", ETH_ALEN}, {"ipvlan0", ETH_ALEN}, {"ipvlan1", ETH_ALEN}, {"veth0_macvtap", ETH_ALEN}, {"veth1_macvtap", ETH_ALEN}, {"macvtap0", ETH_ALEN}, {"macsec0", ETH_ALEN}, {"veth0_to_batadv", ETH_ALEN}, {"veth1_to_batadv", ETH_ALEN}, {"batadv_slave_0", ETH_ALEN}, {"batadv_slave_1", ETH_ALEN}, {"geneve0", ETH_ALEN}, {"geneve1", ETH_ALEN}, {"wg0", 0}, {"wg1", 0}, {"wg2", 0}, }; int sock = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE); if (sock == -1) exit(1); unsigned i; for (i = 0; i < sizeof(devtypes) / sizeof(devtypes[0]); i++) netlink_add_device(&nlmsg, sock, devtypes[i].type, devtypes[i].dev); for (i = 0; i < sizeof(devmasters) / (sizeof(devmasters[0])); i++) { char master[32], slave0[32], veth0[32], slave1[32], veth1[32]; sprintf(slave0, "%s_slave_0", devmasters[i]); sprintf(veth0, "veth0_to_%s", devmasters[i]); netlink_add_veth(&nlmsg, sock, slave0, veth0); sprintf(slave1, "%s_slave_1", devmasters[i]); sprintf(veth1, "veth1_to_%s", devmasters[i]); netlink_add_veth(&nlmsg, sock, slave1, veth1); sprintf(master, "%s0", devmasters[i]); netlink_device_change(&nlmsg, sock, slave0, false, master, 0, 0, NULL); netlink_device_change(&nlmsg, sock, slave1, false, master, 0, 0, NULL); } netlink_device_change(&nlmsg, sock, "bridge_slave_0", true, 0, 0, 0, NULL); netlink_device_change(&nlmsg, sock, "bridge_slave_1", true, 0, 0, 0, NULL); netlink_add_veth(&nlmsg, sock, "hsr_slave_0", "veth0_to_hsr"); netlink_add_veth(&nlmsg, sock, "hsr_slave_1", "veth1_to_hsr"); netlink_add_hsr(&nlmsg, sock, "hsr0", "hsr_slave_0", "hsr_slave_1"); netlink_device_change(&nlmsg, sock, "hsr_slave_0", true, 0, 0, 0, NULL); netlink_device_change(&nlmsg, sock, "hsr_slave_1", true, 0, 0, 0, NULL); netlink_add_veth(&nlmsg, sock, "veth0_virt_wifi", "veth1_virt_wifi"); netlink_add_linked(&nlmsg, sock, "virt_wifi", "virt_wifi0", "veth1_virt_wifi"); netlink_add_veth(&nlmsg, sock, "veth0_vlan", "veth1_vlan"); netlink_add_vlan(&nlmsg, sock, "vlan0", "veth0_vlan", 0, htons(ETH_P_8021Q)); netlink_add_vlan(&nlmsg, sock, "vlan1", "veth0_vlan", 1, htons(ETH_P_8021AD)); netlink_add_macvlan(&nlmsg, sock, "macvlan0", "veth1_vlan"); netlink_add_macvlan(&nlmsg, sock, "macvlan1", "veth1_vlan"); netlink_add_ipvlan(&nlmsg, sock, "ipvlan0", "veth0_vlan", IPVLAN_MODE_L2, 0); netlink_add_ipvlan(&nlmsg, sock, "ipvlan1", "veth0_vlan", IPVLAN_MODE_L3S, IPVLAN_F_VEPA); netlink_add_veth(&nlmsg, sock, "veth0_macvtap", "veth1_macvtap"); netlink_add_linked(&nlmsg, sock, "macvtap", "macvtap0", "veth0_macvtap"); netlink_add_linked(&nlmsg, sock, "macsec", "macsec0", "veth1_macvtap"); char addr[32]; sprintf(addr, DEV_IPV4, 14 + 10); struct in_addr geneve_addr4; if (inet_pton(AF_INET, addr, &geneve_addr4) <= 0) exit(1); struct in6_addr geneve_addr6; if (inet_pton(AF_INET6, "fc00::01", &geneve_addr6) <= 0) exit(1); netlink_add_geneve(&nlmsg, sock, "geneve0", 0, &geneve_addr4, 0); netlink_add_geneve(&nlmsg, sock, "geneve1", 1, 0, &geneve_addr6); netdevsim_add((int)procid, 4); netlink_wireguard_setup(); for (i = 0; i < sizeof(devices) / (sizeof(devices[0])); i++) { char addr[32]; sprintf(addr, DEV_IPV4, i + 10); netlink_add_addr4(&nlmsg, sock, devices[i].name, addr); if (!devices[i].noipv6) { sprintf(addr, DEV_IPV6, i + 10); netlink_add_addr6(&nlmsg, sock, devices[i].name, addr); } uint64_t macaddr = DEV_MAC + ((i + 10ull) << 40); netlink_device_change(&nlmsg, sock, devices[i].name, true, 0, &macaddr, devices[i].macsize, NULL); } close(sock); } static void initialize_netdevices_init(void) { int sock = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE); if (sock == -1) exit(1); struct { const char* type; int macsize; bool noipv6; bool noup; } devtypes[] = { {"nr", 7, true}, {"rose", 5, true, true}, }; unsigned i; for (i = 0; i < sizeof(devtypes) / sizeof(devtypes[0]); i++) { char dev[32], addr[32]; sprintf(dev, "%s%d", devtypes[i].type, (int)procid); sprintf(addr, "172.30.%d.%d", i, (int)procid + 1); netlink_add_addr4(&nlmsg, sock, dev, addr); if (!devtypes[i].noipv6) { sprintf(addr, "fe88::%02x:%02x", i, (int)procid + 1); netlink_add_addr6(&nlmsg, sock, dev, addr); } int macsize = devtypes[i].macsize; uint64_t macaddr = 0xbbbbbb + ((unsigned long long)i << (8 * (macsize - 2))) + (procid << (8 * (macsize - 1))); netlink_device_change(&nlmsg, sock, dev, !devtypes[i].noup, 0, &macaddr, macsize, NULL); } close(sock); } static int read_tun(char* data, int size) { if (tunfd < 0) return -1; int rv = read(tunfd, data, size); if (rv < 0) { if (errno == EAGAIN || errno == EBADFD) return -1; exit(1); } return rv; } static void flush_tun() { char data[1000]; while (read_tun(&data[0], sizeof(data)) != -1) { } } #define MAX_FDS 30 static void setup_cgroups() { if (mkdir("/syzcgroup", 0777)) { } if (mkdir("/syzcgroup/unified", 0777)) { } if (mount("none", "/syzcgroup/unified", "cgroup2", 0, NULL)) { } if (chmod("/syzcgroup/unified", 0777)) { } write_file("/syzcgroup/unified/cgroup.subtree_control", "+cpu +memory +io +pids +rdma"); if (mkdir("/syzcgroup/cpu", 0777)) { } if (mount("none", "/syzcgroup/cpu", "cgroup", 0, "cpuset,cpuacct,perf_event,hugetlb")) { } write_file("/syzcgroup/cpu/cgroup.clone_children", "1"); write_file("/syzcgroup/cpu/cpuset.memory_pressure_enabled", "1"); if (chmod("/syzcgroup/cpu", 0777)) { } if (mkdir("/syzcgroup/net", 0777)) { } if (mount("none", "/syzcgroup/net", "cgroup", 0, "net_cls,net_prio,devices,freezer")) { } if (chmod("/syzcgroup/net", 0777)) { } } static void setup_cgroups_loop() { int pid = getpid(); char file[128]; char cgroupdir[64]; snprintf(cgroupdir, sizeof(cgroupdir), "/syzcgroup/unified/syz%llu", procid); if (mkdir(cgroupdir, 0777)) { } snprintf(file, sizeof(file), "%s/pids.max", cgroupdir); write_file(file, "32"); snprintf(file, sizeof(file), "%s/memory.low", cgroupdir); write_file(file, "%d", 298 << 20); snprintf(file, sizeof(file), "%s/memory.high", cgroupdir); write_file(file, "%d", 299 << 20); snprintf(file, sizeof(file), "%s/memory.max", cgroupdir); write_file(file, "%d", 300 << 20); snprintf(file, sizeof(file), "%s/cgroup.procs", cgroupdir); write_file(file, "%d", pid); snprintf(cgroupdir, sizeof(cgroupdir), "/syzcgroup/cpu/syz%llu", procid); if (mkdir(cgroupdir, 0777)) { } snprintf(file, sizeof(file), "%s/cgroup.procs", cgroupdir); write_file(file, "%d", pid); snprintf(cgroupdir, sizeof(cgroupdir), "/syzcgroup/net/syz%llu", procid); if (mkdir(cgroupdir, 0777)) { } snprintf(file, sizeof(file), "%s/cgroup.procs", cgroupdir); write_file(file, "%d", pid); } static void setup_cgroups_test() { char cgroupdir[64]; snprintf(cgroupdir, sizeof(cgroupdir), "/syzcgroup/unified/syz%llu", procid); if (symlink(cgroupdir, "./cgroup")) { } snprintf(cgroupdir, sizeof(cgroupdir), "/syzcgroup/cpu/syz%llu", procid); if (symlink(cgroupdir, "./cgroup.cpu")) { } snprintf(cgroupdir, sizeof(cgroupdir), "/syzcgroup/net/syz%llu", procid); if (symlink(cgroupdir, "./cgroup.net")) { } } static void setup_common() { if (mount(0, "/sys/fs/fuse/connections", "fusectl", 0, 0)) { } setup_cgroups(); } static void loop(); static void sandbox_common() { prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0); setsid(); 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 = 0; 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(); sandbox_common(); drop_caps(); initialize_netdevices_init(); if (unshare(CLONE_NEWNET)) { } initialize_tun(); initialize_netdevices(); loop(); exit(1); } #define FS_IOC_SETFLAGS _IOW('f', 2, long) static void remove_dir(const char* dir) { int iter = 0; DIR* dp = 0; retry: while (umount2(dir, MNT_DETACH) == 0) { } dp = opendir(dir); if (dp == NULL) { if (errno == EMFILE) { exit(1); } exit(1); } struct dirent* ep = 0; while ((ep = readdir(dp))) { if (strcmp(ep->d_name, ".") == 0 || strcmp(ep->d_name, "..") == 0) continue; char filename[FILENAME_MAX]; snprintf(filename, sizeof(filename), "%s/%s", dir, ep->d_name); while (umount2(filename, MNT_DETACH) == 0) { } struct stat st; if (lstat(filename, &st)) exit(1); if (S_ISDIR(st.st_mode)) { remove_dir(filename); continue; } int i; for (i = 0;; i++) { if (unlink(filename) == 0) break; if (errno == EPERM) { int fd = open(filename, O_RDONLY); if (fd != -1) { long flags = 0; if (ioctl(fd, FS_IOC_SETFLAGS, &flags) == 0) { } close(fd); continue; } } if (errno == EROFS) { break; } if (errno != EBUSY || i > 100) exit(1); if (umount2(filename, MNT_DETACH)) exit(1); } } closedir(dp); for (int i = 0;; i++) { if (rmdir(dir) == 0) break; if (i < 100) { if (errno == EPERM) { int fd = open(dir, O_RDONLY); if (fd != -1) { long flags = 0; if (ioctl(fd, FS_IOC_SETFLAGS, &flags) == 0) { } close(fd); continue; } } if (errno == EROFS) { break; } if (errno == EBUSY) { if (umount2(dir, MNT_DETACH)) exit(1); continue; } if (errno == ENOTEMPTY) { if (iter < 100) { iter++; goto retry; } } } exit(1); } } static void kill_and_wait(int pid, int* status) { kill(-pid, SIGKILL); kill(pid, SIGKILL); for (int 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_loop() { setup_cgroups_loop(); } static void setup_test() { prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0); setpgrp(); setup_cgroups_test(); write_file("/proc/self/oom_score_adj", "1000"); flush_tun(); } static void close_fds() { for (int fd = 3; fd < MAX_FDS; fd++) close(fd); } static void setup_usb() { if (chmod("/dev/raw-gadget", 0666)) exit(1); } static void setup_sysctl() { static 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_enable", "1"}, {"/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/net/ipv4/ping_group_range", "0 65535"}, {"/proc/sys/kernel/keys/gc_delay", "1"}, {"/proc/sys/vm/nr_overcommit_hugepages", "4"}, {"/proc/sys/vm/oom_kill_allocating_task", "1"}, }; 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)); } } 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; for (call = 0; call < 2; 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(); } static void execute_one(void); #define WAIT_FLAGS __WALL static void loop(void) { setup_loop(); int iter = 0; for (;; iter++) { char cwdbuf[32]; sprintf(cwdbuf, "./%d", iter); if (mkdir(cwdbuf, 0777)) exit(1); int pid = fork(); if (pid < 0) exit(1); if (pid == 0) { if (chdir(cwdbuf)) exit(1); 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 < 5000) { continue; } kill_and_wait(pid, &status); break; } remove_dir(cwdbuf); } } uint64_t r[1] = {0xffffffffffffffff}; void execute_call(int call) { intptr_t res = 0; switch (call) { case 0: NONFAILING(memcpy((void*)0x20000300, "/dev/uhid\000", 10)); res = syscall(__NR_openat, 0xffffffffffffff9cul, 0x20000300ul, 2ul, 0ul); if (res != -1) r[0] = res; break; case 1: NONFAILING(*(uint32_t*)0x20000000 = 0); NONFAILING(memcpy((void*)0x20000004, "syz1\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\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\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", 128)); NONFAILING(memcpy((void*)0x20000084, "syz1\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\000\000\000\000\000\000\000\000\000\000\000\000\000" "\000\000\000\000\000", 64)); NONFAILING(memcpy((void*)0x200000c4, "syz0\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\000\000\000\000\000\000\000\000\000\000\000\000\000" "\000\000\000\000\000", 64)); NONFAILING(*(uint64_t*)0x20000104 = 0x200004c0); NONFAILING(*(uint16_t*)0x2000010c = 0x1000); NONFAILING(*(uint16_t*)0x2000010e = 0); NONFAILING(*(uint32_t*)0x20000110 = 0); NONFAILING(*(uint32_t*)0x20000114 = 0); NONFAILING(*(uint32_t*)0x20000118 = 0); NONFAILING(*(uint32_t*)0x2000011c = 0); syscall(__NR_write, r[0], 0x20000000ul, 0x120ul); 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); setup_sysctl(); setup_usb(); install_segv_handler(); for (procid = 0; procid < 6; procid++) { if (fork() == 0) { use_temporary_dir(); do_sandbox_none(); } } sleep(1000000); return 0; }