// https://syzkaller.appspot.com/bug?id=c3c1820847d4446bca796c13af7332da1ee757ef // 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 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 bool write_file(const char* file, const char* what, ...) { char buf[1024]; va_list args; va_start(args, what); vsnprintf(buf, sizeof(buf), what, args); va_end(args); buf[sizeof(buf) - 1] = 0; int len = strlen(buf); int fd = open(file, O_WRONLY | O_CLOEXEC); if (fd == -1) return false; if (write(fd, buf, len) != len) { int err = errno; close(fd); errno = err; return false; } close(fd); return true; } static struct { char* pos; int nesting; struct nlattr* nested[8]; char buf[1024]; } nlmsg; static void netlink_init(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(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(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(void) { struct nlattr* attr = nlmsg.nested[--nlmsg.nesting]; attr->nla_len = nlmsg.pos - (char*)attr; } static int netlink_send(int sock) { 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 (n < sizeof(struct nlmsghdr) + sizeof(struct nlmsgerr)) exit(1); if (hdr->nlmsg_type != NLMSG_ERROR) exit(1); return -((struct nlmsgerr*)(hdr + 1))->error; } static void netlink_add_device_impl(const char* type, const char* name) { struct ifinfomsg hdr; memset(&hdr, 0, sizeof(hdr)); netlink_init(RTM_NEWLINK, NLM_F_EXCL | NLM_F_CREATE, &hdr, sizeof(hdr)); if (name) netlink_attr(IFLA_IFNAME, name, strlen(name)); netlink_nest(IFLA_LINKINFO); netlink_attr(IFLA_INFO_KIND, type, strlen(type)); } static void netlink_add_device(int sock, const char* type, const char* name) { netlink_add_device_impl(type, name); netlink_done(); int err = netlink_send(sock); (void)err; } static void netlink_add_veth(int sock, const char* name, const char* peer) { netlink_add_device_impl("veth", name); netlink_nest(IFLA_INFO_DATA); netlink_nest(VETH_INFO_PEER); nlmsg.pos += sizeof(struct ifinfomsg); netlink_attr(IFLA_IFNAME, peer, strlen(peer)); netlink_done(); netlink_done(); netlink_done(); int err = netlink_send(sock); (void)err; } static void netlink_add_hsr(int sock, const char* name, const char* slave1, const char* slave2) { netlink_add_device_impl("hsr", name); netlink_nest(IFLA_INFO_DATA); int ifindex1 = if_nametoindex(slave1); netlink_attr(IFLA_HSR_SLAVE1, &ifindex1, sizeof(ifindex1)); int ifindex2 = if_nametoindex(slave2); netlink_attr(IFLA_HSR_SLAVE2, &ifindex2, sizeof(ifindex2)); netlink_done(); netlink_done(); int err = netlink_send(sock); (void)err; } static void netlink_device_change(int sock, const char* name, bool up, const char* master, const void* mac, int macsize) { struct ifinfomsg hdr; memset(&hdr, 0, sizeof(hdr)); if (up) hdr.ifi_flags = hdr.ifi_change = IFF_UP; netlink_init(RTM_NEWLINK, 0, &hdr, sizeof(hdr)); netlink_attr(IFLA_IFNAME, name, strlen(name)); if (master) { int ifindex = if_nametoindex(master); netlink_attr(IFLA_MASTER, &ifindex, sizeof(ifindex)); } if (macsize) netlink_attr(IFLA_ADDRESS, mac, macsize); int err = netlink_send(sock); (void)err; } static int netlink_add_addr(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(RTM_NEWADDR, NLM_F_CREATE | NLM_F_REPLACE, &hdr, sizeof(hdr)); netlink_attr(IFA_LOCAL, addr, addrsize); netlink_attr(IFA_ADDRESS, addr, addrsize); return netlink_send(sock); } static void netlink_add_addr4(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(sock, dev, &in_addr, sizeof(in_addr)); (void)err; } static void netlink_add_addr6(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(sock, dev, &in6_addr, sizeof(in6_addr)); (void)err; } static void netlink_add_neigh(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(RTM_NEWNEIGH, NLM_F_EXCL | NLM_F_CREATE, &hdr, sizeof(hdr)); netlink_attr(NDA_DST, addr, addrsize); netlink_attr(NDA_LLADDR, mac, macsize); int err = netlink_send(sock); (void)err; } static int tunfd = -1; static int tun_frags_enabled; #define SYZ_TUN_MAX_PACKET_SIZE 1000 #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(sock, TUN_IFACE, LOCAL_IPV4); netlink_add_addr6(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(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(sock, TUN_IFACE, &in6_addr, sizeof(in6_addr), &macaddr, ETH_ALEN); macaddr = LOCAL_MAC; netlink_device_change(sock, TUN_IFACE, true, 0, &macaddr, ETH_ALEN); close(sock); } #define DEV_IPV4 "172.20.20.%d" #define DEV_IPV6 "fe80::%02x" #define DEV_MAC 0x00aaaaaaaaaa 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}, {"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(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(sock, slave0, veth0); sprintf(slave1, "%s_slave_1", devmasters[i]); sprintf(veth1, "veth1_to_%s", devmasters[i]); netlink_add_veth(sock, slave1, veth1); sprintf(master, "%s0", devmasters[i]); netlink_device_change(sock, slave0, false, master, 0, 0); netlink_device_change(sock, slave1, false, master, 0, 0); } netlink_device_change(sock, "bridge_slave_0", true, 0, 0, 0); netlink_device_change(sock, "bridge_slave_1", true, 0, 0, 0); netlink_add_veth(sock, "hsr_slave_0", "veth0_to_hsr"); netlink_add_veth(sock, "hsr_slave_1", "veth1_to_hsr"); netlink_add_hsr(sock, "hsr0", "hsr_slave_0", "hsr_slave_1"); netlink_device_change(sock, "hsr_slave_0", true, 0, 0, 0); netlink_device_change(sock, "hsr_slave_1", true, 0, 0, 0); for (i = 0; i < sizeof(devices) / (sizeof(devices[0])); i++) { char addr[32]; sprintf(addr, DEV_IPV4, i + 10); netlink_add_addr4(sock, devices[i].name, addr); if (!devices[i].noipv6) { sprintf(addr, DEV_IPV6, i + 10); netlink_add_addr6(sock, devices[i].name, addr); } uint64_t macaddr = DEV_MAC + ((i + 10ull) << 40); netlink_device_change(sock, devices[i].name, true, 0, &macaddr, devices[i].macsize); } 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(sock, dev, addr); if (!devtypes[i].noipv6) { sprintf(addr, "fe88::%02x:%02x", i, (int)procid + 1); netlink_add_addr6(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(sock, dev, !devtypes[i].noup, 0, &macaddr, macsize); } 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[SYZ_TUN_MAX_PACKET_SIZE]; while (read_tun(&data[0], sizeof(data)) != -1) { } } #define USB_DEBUG 0 #define USB_MAX_IFACE_NUM 4 #define USB_MAX_EP_NUM 32 struct usb_iface_index { struct usb_interface_descriptor* iface; struct usb_endpoint_descriptor* eps[USB_MAX_EP_NUM]; unsigned eps_num; }; struct usb_device_index { struct usb_device_descriptor* dev; struct usb_config_descriptor* config; unsigned config_length; struct usb_iface_index ifaces[USB_MAX_IFACE_NUM]; unsigned ifaces_num; }; static bool parse_usb_descriptor(char* buffer, size_t length, struct usb_device_index* index) { if (length < sizeof(*index->dev) + sizeof(*index->config)) return false; memset(index, 0, sizeof(*index)); index->dev = (struct usb_device_descriptor*)buffer; index->config = (struct usb_config_descriptor*)(buffer + sizeof(*index->dev)); index->config_length = length - sizeof(*index->dev); size_t offset = 0; while (true) { if (offset + 1 >= length) break; uint8_t desc_length = buffer[offset]; uint8_t desc_type = buffer[offset + 1]; if (desc_length <= 2) break; if (offset + desc_length > length) break; if (desc_type == USB_DT_INTERFACE && index->ifaces_num < USB_MAX_IFACE_NUM) { struct usb_interface_descriptor* iface = (struct usb_interface_descriptor*)(buffer + offset); index->ifaces[index->ifaces_num++].iface = iface; } if (desc_type == USB_DT_ENDPOINT && index->ifaces_num > 0) { struct usb_iface_index* iface = &index->ifaces[index->ifaces_num - 1]; if (iface->eps_num < USB_MAX_EP_NUM) iface->eps[iface->eps_num++] = (struct usb_endpoint_descriptor*)(buffer + offset); } offset += desc_length; } return true; } enum usb_fuzzer_event_type { USB_FUZZER_EVENT_INVALID, USB_FUZZER_EVENT_CONNECT, USB_FUZZER_EVENT_DISCONNECT, USB_FUZZER_EVENT_SUSPEND, USB_FUZZER_EVENT_RESUME, USB_FUZZER_EVENT_CONTROL, }; struct usb_fuzzer_event { uint32_t type; uint32_t length; char data[0]; }; struct usb_fuzzer_init { uint64_t speed; const char* driver_name; const char* device_name; }; struct usb_fuzzer_ep_io { uint16_t ep; uint16_t flags; uint32_t length; char data[0]; }; #define USB_FUZZER_IOCTL_INIT _IOW('U', 0, struct usb_fuzzer_init) #define USB_FUZZER_IOCTL_RUN _IO('U', 1) #define USB_FUZZER_IOCTL_EVENT_FETCH _IOR('U', 2, struct usb_fuzzer_event) #define USB_FUZZER_IOCTL_EP0_WRITE _IOW('U', 3, struct usb_fuzzer_ep_io) #define USB_FUZZER_IOCTL_EP0_READ _IOWR('U', 4, struct usb_fuzzer_ep_io) #define USB_FUZZER_IOCTL_EP_ENABLE _IOW('U', 5, struct usb_endpoint_descriptor) #define USB_FUZZER_IOCTL_EP_WRITE _IOW('U', 7, struct usb_fuzzer_ep_io) #define USB_FUZZER_IOCTL_EP_READ _IOWR('U', 8, struct usb_fuzzer_ep_io) #define USB_FUZZER_IOCTL_CONFIGURE _IO('U', 9) #define USB_FUZZER_IOCTL_VBUS_DRAW _IOW('U', 10, uint32_t) int usb_fuzzer_open() { return open("/sys/kernel/debug/usb-fuzzer", O_RDWR); } int usb_fuzzer_init(int fd, uint32_t speed, const char* driver, const char* device) { struct usb_fuzzer_init arg; arg.speed = speed; arg.driver_name = driver; arg.device_name = device; return ioctl(fd, USB_FUZZER_IOCTL_INIT, &arg); } int usb_fuzzer_run(int fd) { return ioctl(fd, USB_FUZZER_IOCTL_RUN, 0); } int usb_fuzzer_event_fetch(int fd, struct usb_fuzzer_event* event) { return ioctl(fd, USB_FUZZER_IOCTL_EVENT_FETCH, event); } int usb_fuzzer_ep0_write(int fd, struct usb_fuzzer_ep_io* io) { return ioctl(fd, USB_FUZZER_IOCTL_EP0_WRITE, io); } int usb_fuzzer_ep0_read(int fd, struct usb_fuzzer_ep_io* io) { return ioctl(fd, USB_FUZZER_IOCTL_EP0_READ, io); } int usb_fuzzer_ep_write(int fd, struct usb_fuzzer_ep_io* io) { return ioctl(fd, USB_FUZZER_IOCTL_EP_WRITE, io); } int usb_fuzzer_ep_read(int fd, struct usb_fuzzer_ep_io* io) { return ioctl(fd, USB_FUZZER_IOCTL_EP_READ, io); } int usb_fuzzer_ep_enable(int fd, struct usb_endpoint_descriptor* desc) { return ioctl(fd, USB_FUZZER_IOCTL_EP_ENABLE, desc); } int usb_fuzzer_configure(int fd) { return ioctl(fd, USB_FUZZER_IOCTL_CONFIGURE, 0); } int usb_fuzzer_vbus_draw(int fd, uint32_t power) { return ioctl(fd, USB_FUZZER_IOCTL_VBUS_DRAW, power); } #define USB_MAX_PACKET_SIZE 1024 struct usb_fuzzer_control_event { struct usb_fuzzer_event inner; struct usb_ctrlrequest ctrl; char data[USB_MAX_PACKET_SIZE]; }; struct usb_fuzzer_ep_io_data { struct usb_fuzzer_ep_io inner; char data[USB_MAX_PACKET_SIZE]; }; struct vusb_connect_string_descriptor { uint32_t len; char* str; } __attribute__((packed)); struct vusb_connect_descriptors { uint32_t qual_len; char* qual; uint32_t bos_len; char* bos; uint32_t strs_len; struct vusb_connect_string_descriptor strs[0]; } __attribute__((packed)); static const char default_string[] = {8, USB_DT_STRING, 's', 0, 'y', 0, 'z', 0}; static const char default_lang_id[] = {4, USB_DT_STRING, 0x09, 0x04}; static bool lookup_connect_response(struct vusb_connect_descriptors* descs, struct usb_device_index* index, struct usb_ctrlrequest* ctrl, char** response_data, uint32_t* response_length) { uint8_t str_idx; switch (ctrl->bRequestType & USB_TYPE_MASK) { case USB_TYPE_STANDARD: switch (ctrl->bRequest) { case USB_REQ_GET_DESCRIPTOR: switch (ctrl->wValue >> 8) { case USB_DT_DEVICE: *response_data = (char*)index->dev; *response_length = sizeof(*index->dev); return true; case USB_DT_CONFIG: *response_data = (char*)index->config; *response_length = index->config_length; return true; case USB_DT_STRING: str_idx = (uint8_t)ctrl->wValue; if (descs && str_idx < descs->strs_len) { *response_data = descs->strs[str_idx].str; *response_length = descs->strs[str_idx].len; return true; } if (str_idx == 0) { *response_data = (char*)&default_lang_id[0]; *response_length = default_lang_id[0]; return true; } *response_data = (char*)&default_string[0]; *response_length = default_string[0]; return true; case USB_DT_BOS: *response_data = descs->bos; *response_length = descs->bos_len; return true; case USB_DT_DEVICE_QUALIFIER: if (!descs->qual) { struct usb_qualifier_descriptor* qual = (struct usb_qualifier_descriptor*)response_data; qual->bLength = sizeof(*qual); qual->bDescriptorType = USB_DT_DEVICE_QUALIFIER; qual->bcdUSB = index->dev->bcdUSB; qual->bDeviceClass = index->dev->bDeviceClass; qual->bDeviceSubClass = index->dev->bDeviceSubClass; qual->bDeviceProtocol = index->dev->bDeviceProtocol; qual->bMaxPacketSize0 = index->dev->bMaxPacketSize0; qual->bNumConfigurations = index->dev->bNumConfigurations; qual->bRESERVED = 0; *response_length = sizeof(*qual); return true; } *response_data = descs->qual; *response_length = descs->qual_len; return true; default: exit(1); return false; } break; default: exit(1); return false; } break; default: exit(1); return false; } return false; } static volatile long syz_usb_connect(volatile long a0, volatile long a1, volatile long a2, volatile long a3) { uint64_t speed = a0; uint64_t dev_len = a1; char* dev = (char*)a2; struct vusb_connect_descriptors* descs = (struct vusb_connect_descriptors*)a3; if (!dev) { return -1; } struct usb_device_index index; memset(&index, 0, sizeof(index)); int rv = 0; rv = parse_usb_descriptor(dev, dev_len, &index); if (!rv) { return rv; } int fd = usb_fuzzer_open(); if (fd < 0) { return fd; } char device[32]; sprintf(&device[0], "dummy_udc.%llu", procid); rv = usb_fuzzer_init(fd, speed, "dummy_udc", &device[0]); if (rv < 0) { return rv; } rv = usb_fuzzer_run(fd); if (rv < 0) { return rv; } bool done = false; while (!done) { struct usb_fuzzer_control_event event; event.inner.type = 0; event.inner.length = sizeof(event.ctrl); rv = usb_fuzzer_event_fetch(fd, (struct usb_fuzzer_event*)&event); if (rv < 0) { return rv; } if (event.inner.type != USB_FUZZER_EVENT_CONTROL) continue; bool response_found = false; char* response_data = NULL; uint32_t response_length = 0; if (event.ctrl.bRequestType & USB_DIR_IN) { response_found = lookup_connect_response( descs, &index, &event.ctrl, &response_data, &response_length); if (!response_found) { return -1; } } else { if ((event.ctrl.bRequestType & USB_TYPE_MASK) != USB_TYPE_STANDARD || event.ctrl.bRequest != USB_REQ_SET_CONFIGURATION) { exit(1); return -1; } done = true; } if (done) { rv = usb_fuzzer_vbus_draw(fd, index.config->bMaxPower); if (rv < 0) { return rv; } rv = usb_fuzzer_configure(fd); if (rv < 0) { return rv; } unsigned ep; for (ep = 0; ep < index.ifaces[0].eps_num; ep++) { rv = usb_fuzzer_ep_enable(fd, index.ifaces[0].eps[ep]); if (rv < 0) { } else { } } } struct usb_fuzzer_ep_io_data response; response.inner.ep = 0; response.inner.flags = 0; if (response_length > sizeof(response.data)) response_length = 0; if (event.ctrl.wLength < response_length) response_length = event.ctrl.wLength; response.inner.length = response_length; if (response_data) memcpy(&response.data[0], response_data, response_length); else memset(&response.data[0], 0, response_length); if (event.ctrl.bRequestType & USB_DIR_IN) { rv = usb_fuzzer_ep0_write(fd, (struct usb_fuzzer_ep_io*)&response); } else { rv = usb_fuzzer_ep0_read(fd, (struct usb_fuzzer_ep_io*)&response); } if (rv < 0) { return rv; } } sleep_ms(200); return fd; } static long syz_open_dev(volatile long a0, volatile long a1, volatile long a2) { if (a0 == 0xc || a0 == 0xb) { char buf[128]; sprintf(buf, "/dev/%s/%d:%d", a0 == 0xc ? "char" : "block", (uint8_t)a1, (uint8_t)a2); return open(buf, O_RDWR, 0); } else { char buf[1024]; char* hash; strncpy(buf, (char*)a0, sizeof(buf) - 1); buf[sizeof(buf) - 1] = 0; while ((hash = strchr(buf, '#'))) { *hash = '0' + (char)(a1 % 10); a1 /= 10; } return open(buf, a2, 0); } } 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"); 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")) { } } void initialize_cgroups() { if (mkdir("./syz-tmp/newroot/syzcgroup", 0700)) exit(1); if (mkdir("./syz-tmp/newroot/syzcgroup/unified", 0700)) exit(1); if (mkdir("./syz-tmp/newroot/syzcgroup/cpu", 0700)) exit(1); if (mkdir("./syz-tmp/newroot/syzcgroup/net", 0700)) exit(1); unsigned bind_mount_flags = MS_BIND | MS_REC | MS_PRIVATE; if (mount("/syzcgroup/unified", "./syz-tmp/newroot/syzcgroup/unified", NULL, bind_mount_flags, NULL)) { } if (mount("/syzcgroup/cpu", "./syz-tmp/newroot/syzcgroup/cpu", NULL, bind_mount_flags, NULL)) { } if (mount("/syzcgroup/net", "./syz-tmp/newroot/syzcgroup/net", NULL, bind_mount_flags, NULL)) { } } 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); setpgrp(); 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 (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 real_uid; static int real_gid; __attribute__((aligned(64 << 10))) static char sandbox_stack[1 << 20]; static int namespace_sandbox_proc(void* arg) { sandbox_common(); write_file("/proc/self/setgroups", "deny"); if (!write_file("/proc/self/uid_map", "0 %d 1\n", real_uid)) exit(1); if (!write_file("/proc/self/gid_map", "0 %d 1\n", real_gid)) exit(1); initialize_netdevices_init(); if (unshare(CLONE_NEWNET)) exit(1); initialize_tun(); initialize_netdevices(); if (mkdir("./syz-tmp", 0777)) exit(1); if (mount("", "./syz-tmp", "tmpfs", 0, NULL)) exit(1); if (mkdir("./syz-tmp/newroot", 0777)) exit(1); if (mkdir("./syz-tmp/newroot/dev", 0700)) exit(1); unsigned bind_mount_flags = MS_BIND | MS_REC | MS_PRIVATE; if (mount("/dev", "./syz-tmp/newroot/dev", NULL, bind_mount_flags, NULL)) exit(1); if (mkdir("./syz-tmp/newroot/proc", 0700)) exit(1); if (mount(NULL, "./syz-tmp/newroot/proc", "proc", 0, NULL)) exit(1); if (mkdir("./syz-tmp/newroot/selinux", 0700)) exit(1); const char* selinux_path = "./syz-tmp/newroot/selinux"; if (mount("/selinux", selinux_path, NULL, bind_mount_flags, NULL)) { if (errno != ENOENT) exit(1); if (mount("/sys/fs/selinux", selinux_path, NULL, bind_mount_flags, NULL) && errno != ENOENT) exit(1); } if (mkdir("./syz-tmp/newroot/sys", 0700)) exit(1); if (mount("/sys", "./syz-tmp/newroot/sys", 0, bind_mount_flags, NULL)) exit(1); initialize_cgroups(); if (mkdir("./syz-tmp/pivot", 0777)) exit(1); if (syscall(SYS_pivot_root, "./syz-tmp", "./syz-tmp/pivot")) { if (chdir("./syz-tmp")) exit(1); } else { if (chdir("/")) exit(1); if (umount2("./pivot", MNT_DETACH)) exit(1); } if (chroot("./newroot")) exit(1); if (chdir("/")) exit(1); drop_caps(); loop(); exit(1); } static int do_sandbox_namespace(void) { int pid; setup_common(); real_uid = getuid(); real_gid = getgid(); mprotect(sandbox_stack, 4096, PROT_NONE); pid = clone(namespace_sandbox_proc, &sandbox_stack[sizeof(sandbox_stack) - 64], CLONE_NEWUSER | CLONE_NEWPID, 0); return wait_for_loop(pid); } #define FS_IOC_SETFLAGS _IOW('f', 2, long) static void remove_dir(const char* dir) { DIR* dp; struct dirent* ep; int iter = 0; retry: while (umount2(dir, MNT_DETACH) == 0) { } dp = opendir(dir); if (dp == NULL) { if (errno == EMFILE) { exit(1); } exit(1); } 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); int i; for (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); 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_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() { int fd; for (fd = 3; fd < 30; fd++) close(fd); } static void execute_one(void); #define WAIT_FLAGS __WALL static void loop(void) { setup_loop(); int iter; for (iter = 0;; 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(); close_fds(); 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; } remove_dir(cwdbuf); } } void execute_one(void) { *(uint8_t*)0x20000000 = 0x12; *(uint8_t*)0x20000001 = 1; *(uint16_t*)0x20000002 = 0; *(uint8_t*)0x20000004 = 0x11; *(uint8_t*)0x20000005 = 0xf7; *(uint8_t*)0x20000006 = 0x9a; *(uint8_t*)0x20000007 = 8; *(uint16_t*)0x20000008 = 0xa07; *(uint16_t*)0x2000000a = 0xda; *(uint16_t*)0x2000000c = 0xad48; *(uint8_t*)0x2000000e = 0; *(uint8_t*)0x2000000f = 0; *(uint8_t*)0x20000010 = 0; *(uint8_t*)0x20000011 = 1; *(uint8_t*)0x20000012 = 9; *(uint8_t*)0x20000013 = 2; *(uint16_t*)0x20000014 = 0x24; *(uint8_t*)0x20000016 = 1; *(uint8_t*)0x20000017 = 0; *(uint8_t*)0x20000018 = 0; *(uint8_t*)0x20000019 = 0; *(uint8_t*)0x2000001a = 0; *(uint8_t*)0x2000001b = 9; *(uint8_t*)0x2000001c = 4; *(uint8_t*)0x2000001d = 0xb9; *(uint8_t*)0x2000001e = 0; *(uint8_t*)0x2000001f = 2; *(uint8_t*)0x20000020 = 0xc7; *(uint8_t*)0x20000021 = 0x50; *(uint8_t*)0x20000022 = 0xdc; *(uint8_t*)0x20000023 = 0; *(uint8_t*)0x20000024 = 9; *(uint8_t*)0x20000025 = 5; *(uint8_t*)0x20000026 = 0x85; *(uint8_t*)0x20000027 = 0xb; *(uint16_t*)0x20000028 = 0; *(uint8_t*)0x2000002a = 0; *(uint8_t*)0x2000002b = 0; *(uint8_t*)0x2000002c = 0; *(uint8_t*)0x2000002d = 9; *(uint8_t*)0x2000002e = 5; *(uint8_t*)0x2000002f = 1; *(uint8_t*)0x20000030 = 3; *(uint16_t*)0x20000031 = 0; *(uint8_t*)0x20000033 = 0; *(uint8_t*)0x20000034 = 0; *(uint8_t*)0x20000035 = 0; syz_usb_connect(0, 0x36, 0x20000000, 0); syz_open_dev(0xc, 0xb4, 0); } int main(void) { syscall(__NR_mmap, 0x20000000, 0x1000000, 3, 0x32, -1, 0); use_temporary_dir(); do_sandbox_namespace(); return 0; }