// https://syzkaller.appspot.com/bug?id=81a0ddeb9cf1a8abde405132be80e5a3ef4c3a62 // 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 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); } 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_RELAXED)) 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[1024]; }; static struct nlmsg nlmsg; 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; 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 (hdr->nlmsg_type == NLMSG_DONE) { *reply_len = 0; 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_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_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 int tunfd = -1; static int tun_frags_enabled; #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 #define IFF_NAPI_FRAGS 0x0020 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 | IFF_NAPI | IFF_NAPI_FRAGS; if (ioctl(tunfd, TUNSETIFF, (void*)&ifr) < 0) { ifr.ifr_flags = IFF_TAP | IFF_NO_PI; if (ioctl(tunfd, TUNSETIFF, (void*)&ifr) < 0) exit(1); } if (ioctl(tunfd, TUNGETIFF, (void*)&ifr) < 0) exit(1); tun_frags_enabled = (ifr.ifr_flags & IFF_NAPI_FRAGS) != 0; 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 = 239; #define DEVLINK_FAMILY_NAME "devlink" #define DEVLINK_CMD_PORT_GET 5 #define DEVLINK_CMD_RELOAD 37 #define DEVLINK_ATTR_BUS_NAME 1 #define DEVLINK_ATTR_DEV_NAME 2 #define DEVLINK_ATTR_NETDEV_NAME 7 #define DEVLINK_ATTR_NETNS_FD 137 static int netlink_devlink_id_get(struct nlmsg* nlmsg, int sock) { struct genlmsghdr genlhdr; struct nlattr* attr; int err, n; uint16_t id = 0; 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, DEVLINK_FAMILY_NAME, strlen(DEVLINK_FAMILY_NAME) + 1); err = netlink_send_ext(nlmsg, sock, GENL_ID_CTRL, &n); if (err) { return -1; } 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); /* recv ack */ return id; } static void netlink_devlink_netns_move(const char* bus_name, const char* dev_name, int netns_fd) { struct genlmsghdr genlhdr; int sock; int id; sock = socket(AF_NETLINK, SOCK_RAW, NETLINK_GENERIC); if (sock == -1) exit(1); id = netlink_devlink_id_get(&nlmsg, sock); if (id == -1) goto error; memset(&genlhdr, 0, sizeof(genlhdr)); genlhdr.cmd = DEVLINK_CMD_RELOAD; netlink_init(&nlmsg, id, 0, &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); netlink_attr(&nlmsg, DEVLINK_ATTR_NETNS_FD, &netns_fd, sizeof(netns_fd)); netlink_send(&nlmsg, sock); error: close(sock); } 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_devlink_id_get(&nlmsg, sock); 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) { 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); } static void initialize_devlink_pci(void) { int netns = open("/proc/self/ns/net", O_RDONLY); if (netns == -1) exit(1); int ret = setns(kInitNetNsFd, 0); if (ret == -1) exit(1); netlink_devlink_netns_move("pci", "0000:00:10.0", netns); ret = setns(netns, 0); if (ret == -1) exit(1); close(netns); initialize_devlink_ports("pci", "0000:00:10.0", "netpci"); } #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); write_file("/sys/bus/netdevsim/new_device", buf); snprintf(buf, sizeof(buf), "netdevsim%d", addr); initialize_devlink_ports("netdevsim", buf, "netdevsim"); } 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}, }; const char* devmasters[] = {"bridge", "bond", "team"}; 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}, }; 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); netdevsim_add((int)procid, 4); 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) return -1; if (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_common() { if (mount(0, "/sys/fs/fuse/connections", "fusectl", 0, 0)) { } } static void loop(); static void sandbox_common() { prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0); setpgrp(); 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 = 0; setrlimit(RLIMIT_CORE, &rlim); rlim.rlim_cur = rlim.rlim_max = 256; setrlimit(RLIMIT_NOFILE, &rlim); if (unshare(CLONE_NEWNS)) { } 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); } 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_devlink_pci(); initialize_tun(); initialize_netdevices(); loop(); exit(1); } 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"); flush_tun(); } static void close_fds() { int fd; for (fd = 3; fd < MAX_FDS; fd++) close(fd); } 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 < 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, 45); 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) { 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: res = syscall(__NR_socket, 0x2000000000000021ul, 2ul, 2); if (res != -1) r[0] = res; break; case 1: res = syscall(__NR_socket, 0x2000000000000021ul, 2ul, 2); if (res != -1) r[1] = res; break; case 2: *(uint16_t*)0x20000040 = 0x21; *(uint16_t*)0x20000042 = 0; *(uint16_t*)0x20000044 = 2; *(uint16_t*)0x20000046 = 0x10; *(uint16_t*)0x20000048 = 2; *(uint16_t*)0x2000004a = htobe16(0x4e21); *(uint32_t*)0x2000004c = htobe32(0x7f000001); syscall(__NR_connect, r[1], 0x20000040ul, 0x24ul); break; case 3: *(uint64_t*)0x20005c00 = 0; *(uint32_t*)0x20005c08 = 0; *(uint64_t*)0x20005c10 = 0; *(uint64_t*)0x20005c18 = 0; *(uint64_t*)0x20005c20 = 0x20000600; memcpy( (void*)0x20000600, "\x18\x00\x00\x00\x00\x00\x00\x00\x10\x01\x00\x00\x01\x00\x00\x00\x77" "\x00\x00\xf2\x00\x00\x00\x00\xa6\xe2\x17\xb9\x1c\x3b\x0d\x87\x37\x22" "\xb4\x1a\xfb\x8e\xd5\x8f\x21\x09\xe4\x48\xe6\xcc\x4b\xd0\xf1\x1a\x26" "\xf4\x23\x3e\x3b\xa1\xff\x40\xe0\x62\xa4\x3f\x80\xb1\xba\xe2\x72\x83" "\x16\xe6\x3e\x58\xaf\xdf\x28\x47\x32\xbd\x1e\x19\x70\x88\x1d\xdd\x3c" "\x9f\x31\x0f\x82\x7c\x19\x5f\x3c\x5d\x57\xc6\x7a\x08\x46\x65\x17\xba" "\x13\x00\x00\x00\x00\x85\x80\x03\xff\xff\xff\xff\xff\xff\xff\xff\x3e" "\x26\xb5\xca\x26\xbb\x43\x4d\xbd\x0e\x48\x85\xc2\x14\xe5\x77\xbb\x08" "\x18\x76\xe6\x3e\x7c\x28\x34\x57\x39\x25\xdb\x8b\x54\xb3\x3d\xa7\xb9" "\xc7\xae\xfc\xa1\xf9\xc4\x9c\x64\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x00\x61\xe2\x44\x8f\x23\xa7\xe4\x97\x36\xa3\x35\x44\x0c\x5b" "\x76\x81\xc5\x8d\xc6\x47\x49\x4f\x0d\xbc\x81\x1b\xec\xd7\xc4\x87\xd2" "\x83\xb2\xd0\x57\x45\x10\xc4\xfd\xbb\x54\xc6\x1b\xa9\xe6\x35\xc0\xb3" "\xa3\xdf\x61\x0d\x99\x75\xd1\xd9\x57\x0b\x38\x02\x6b\x25\x98\x15\xdb" "\xa5\x98\xff\xa0\x69\xc0\x1b\x3d\x38\x6c\x15\xd3\x4a\x59\x18\xd6\x90" "\x91\x92\xec\x97\x03\x2c\x32\x00\x44\xfa\x93\x4b\xf9\x44\xd6\xd5\xce" "\x62\x1d\x91\xc1\x7f\x1c\x43\x77\xa5\x4c\x7f\xeb\xb4\x6f\x83\xa7\x84" "\x7a\x97\x25\x9b\x8f\x1f\xca\x2c\x28\x16\x02\x3b\x60\x41\x73\x88\x19" "\x6a\x22\x09\x1c\xdf\x82\xe8\xe0\x29\x1f\x40\x82\xd9\x2d\x0a\xe7\x6b" "\x94\xa1\x86\x47\xbb\x44\xcb\xe9\x36\x6a\x08\xfb\x3f\x05\x02\x64\x43" "\x07\xc5\x10\x85\xf7\x21\x5f\xd4\x46\x35\xe5\x96\x7f\x21\xe8\xf5\x9b" "\xd0\x21\xf3\x09\xd9\x10\xcb\x5d\x37\xcb\x16\x45\x02\x44\xef\x26\x1a" "\x37\x25\x5a\x06\xc9\x7f\x19\xfa\x0e\x68\x83\x65\x43\x17\x47\x45\x68" "\x40\x37\xcc\x7b\xba\x99\xaa\x1c\xbe\xfc\xdd\x62\xf7\x99\xa5\xfb\x35" "\xab\xc5\xaf\x3a\xb4\x3a\x5f\xc4\x0e\xb3\x52\xe6\xff\x07\x8f\xad\x68" "\x18\x28\x45\xf1\xf6\xb7\xff\x6c\x20\x0c\x10\x3b\x64\x60\x84\x04\xb4" "\x1f\xce\x73\x18\x6e\x55\x19\x3d\x3d\x96\xfa\xab\x58\x74\x48\x34\x9b" "\x35\xe4\x31\x91\x4b\xfd\xe3\xc0\x7f\x14\x19\xda\xc1\x19\x95\xad\xed" "\x30\xb4\x4e\xad\x71\x42\xa7\xb3\x97\xa9\x13\xf6\xba\xc2\xea\xc4\x1c" "\x32\xd1\x08\x63\xc3\xe6\xdd\x9e\x88\xd4\x48\x42\x95\x1e\x15\xd6\xd6" "\x31\x99\x5f\x07\x14\x34", 516); *(uint64_t*)0x20005c28 = 0x18; *(uint32_t*)0x20005c30 = 0; *(uint32_t*)0x20005c38 = 0; syscall(__NR_sendmmsg, r[1], 0x20005c00ul, 1ul, 0x4048000ul); break; case 4: *(uint64_t*)0x20003180 = 0; *(uint32_t*)0x20003188 = 0; *(uint64_t*)0x20003190 = 0; *(uint64_t*)0x20003198 = 0; *(uint64_t*)0x200031a0 = 0; *(uint64_t*)0x200031a8 = 0; *(uint32_t*)0x200031b0 = 0; *(uint32_t*)0x200031b8 = 0x40; *(uint64_t*)0x200031c0 = 0; *(uint32_t*)0x200031c8 = 0; *(uint64_t*)0x200031d0 = 0; *(uint64_t*)0x200031d8 = 0; *(uint64_t*)0x200031e0 = 0; *(uint64_t*)0x200031e8 = 0; *(uint32_t*)0x200031f0 = 0; *(uint32_t*)0x200031f8 = 2; syscall(__NR_recvmmsg, r[1], 0x20003180ul, 2ul, 0ul, 0ul); break; case 5: *(uint16_t*)0x20000040 = 0x21; *(uint16_t*)0x20000042 = 0; *(uint16_t*)0x20000044 = 2; *(uint16_t*)0x20000046 = 0x10; *(uint16_t*)0x20000048 = 2; *(uint16_t*)0x2000004a = htobe16(0x4e21); *(uint32_t*)0x2000004c = htobe32(0); syscall(__NR_connect, r[0], 0x20000040ul, 0x24ul); break; case 6: *(uint64_t*)0x20005c00 = 0; *(uint32_t*)0x20005c08 = 0; *(uint64_t*)0x20005c10 = 0; *(uint64_t*)0x20005c18 = 0; *(uint64_t*)0x20005c20 = 0x20000080; memcpy( (void*)0x20000080, "\x18\x00\x00\x00\x00\x00\x00\x00\x10\x01\x00\x00\x01\x00\x00\x00\x77" "\x00\x00\xf2\x00\x00\x00\x00\xa6\xe2\x17\xb9\x1c\x3b\x0d\x87\x37\x22" "\xb4\x1a\xfb\x8e\xd5\x8f\x21\x09\xe4\x4c\xe6\xcc\x4b\xd0\xf1\x1a\x26" "\xf4\x23\x3e\x3b\xa1\xff\x40\xe0\x62\xa4\x3f\x80\xb1\xba\xe2\x72\x83" "\x16\xe6\x3e\x58\xaf\xdf\x28\x47\x32\xbd\x1e\x19\x70\x88\x1d\xdd\x3c" "\x9f\x31\x0f\x82\x7c\x19\x5f\x3c\x5d\x57\xc6\x7a\x08\x46\x65\x17\xba" "\x13\x00\x00\x00\x00\x85\x80\x03\xff\xff\xff\xff\xff\xff\xff\xff\x3e" "\x26\xb5\xca\x26\xbb\x43\x4d\xbd\x0e\x48\x85\xc2\x14\xe5\x77\xbb\x08" "\x18\x76\x7c\x28\x34\x57\x20\x00\x00\x00\x00\x00\x00\x00\xb9\xc7\xae" "\xfc\xa1\xf9\xc4\x9c\x64\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x61\xe2\x44\x8f\x23\xa7\xe4\x97\x36\xa3\x35\x44\x0c\x5b\x76\x81" "\xc5\x8d\xc6\x47\x49\x4f\x0d\xbc\x81\x1b\xec\xd7\xc4\x87\xd2\x83\xb2" "\xd0\x57\x45\x10\xc4\xfd\xbb\x54\xc6\x1b\xa9\xe6\x35\xc0\xb3\xa3\xdf" "\x61\x0d\x99\x75\xd1\xd9\x57\x0b\x38\x02\x6b\x25\x98\x15\xdb\xa5\x98" "\xff\xa0\x69\xc0\x1b\x3d\x38\x6c\x15\xd3\x47\x29\x49\x47\xa8\x3b\xe6" "\x97\x97\x03\x2c\x32\x00\x44\xfa\x93\x4b\xf9\x44\xd6\xd5\xce\x62\x1d" "\x91\xc1\x7f\x1c\x43\x77\xa5\x4c\x7f\xeb\xb4\x6f\x83\xa7\x84\x7a\x97" "\x25\x9b\x8f\x1f\xca\x2c\x28\x16\x02\x3b\x60\x41\x73\x88\x19\x68\x22" "\x09\x1c\xdf\x82\xe8\xe0\x29\x1f\x40\x82\xd9\x2d\x0a\xe7\x6b\x94\xa1" "\x86\x47\xbb\x44\xcb\xe9\x36\x6a\x08\xfb\x3f\x05\x02\x64\x43\x07\xc5" "\x10\x85\xf7\x21\x5f\xd4\x46\x35\xe5\x96\x7f\x21\xe8\xf5\x9b\xd0\x21" "\xf3\x09\xd9\x10\xcb\x5d\x37\xcb\x16\x45\x02\x44\xef\x26\x1a\x37\x25" "\x5a\x06\xc9\x7f\x19\xfa\x0e\x68\x83\x65\x43\x17\x47\x45\x68\x40\x37" "\xcc\x7b\xba\x99\xaa\x1c\xbe\xfc\xdd\x62\xf7\x99\xa5\xfb\x35\xab\xc5" "\xaf\x3a\xb4\x3a\x5f\xc4\x0e\xb3\x52\xe6\xff\x07\x8f\xad\x68\x18\x28" "\x45\xf1\xf6\xb7\xff\x6c\x20\x0c\x10\x3b\x64\x60\x84\x04\xb4\x1f\xce" "\x73\x18\x6e\x55\x19\x3d\x3d\x96\xfa\xab\x58\x74\x48\x34\x9b\x35\xe4" "\x31\x91\x4b\xfd\xe3\xc0\x7f\x14\x19\xda\xc1\x19\x95\xad\xed\x30\xb4" "\x4e\xad\x71\x42\xa7\xb3\x97\xb1\x13\xf6\xba\xc2\xea\xc4\x1c\x32\xd1" "\x08\x63\xc3\xe6\xdd\x9e\x88\xd4\x48\x42\x95\x1e\x15\xd6\xd6\x31\x99" "\x5f\x07\x14\x34\x00\x00\x67\x6f\x25\x1e\x6d\x98\xf2\x88\x73\x78\x37" "\x75\x3a\x0a\xa6\x86\x76\x04\xdd\x59\x14\x20\x25\xa0\x96\x1a\xe7\xb4" "\x7a\x4c\xd3\x44\xbd\x68\x4b\xfe\xfc\xd5\x5d\x6f\x8e\x10\x4f\x83\x81" "\x0b\x8a\x4d\xe6\xd0\xd1\xcc\x60\xf5\x1d\x44\x3f\x68\x68\xe7\x89\x0d" "\x35\xdf\x92\x16\x31\xea\xf9\xfa\xd0\xa8\xbd\x0b\xd2\x2a\x34\xc8\xd3" "\x15\x5b\x3a\x47\xf0\x78\xd3\xb3\xec\x7b\xb4\x2d\x49\x3c\xf5\xd1\xea" "\xb7\xdf\xfb\x3f\xb2\x1c\x2f\xf1\x4b\xee\x85\x24\x90\x1c\xf5\xd6\x2a" "\xe4\xa3\x6c\xa5\x07\xa6\xb2\x0e\xee\x19\x4a\xf3\x5f\xf4\x00\x92\xc7" "\xc4\xe2\x97\xa2\x5b\x20\x09\x0b\x01\x04\x85\x9c\xdd\xdf\xbd\x65\x0d" "\xec\xdd\xff\xb8\x23\x1f\x70", 670); *(uint64_t*)0x20005c28 = 0x18; *(uint32_t*)0x20005c30 = 0; *(uint32_t*)0x20005c38 = 0; syscall(__NR_sendmmsg, r[0], 0x20005c00ul, 1ul, 0x4048000ul); break; } } int main(void) { syscall(__NR_mmap, 0x20000000ul, 0x1000000ul, 3ul, 0x32ul, -1, 0); for (procid = 0; procid < 6; procid++) { if (fork() == 0) { do_sandbox_none(); } } sleep(1000000); return 0; }