// https://syzkaller.appspot.com/bug?id=8da93ee4eda48fa44e821d8f73fda27bb8737b45 // autogenerated by syzkaller (https://github.com/google/syzkaller) #define _GNU_SOURCE #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include static unsigned long long procid; static __thread int clone_ongoing; static __thread int skip_segv; static __thread jmp_buf segv_env; static void segv_handler(int sig, siginfo_t* info, void* ctx) { if (__atomic_load_n(&clone_ongoing, __ATOMIC_RELAXED) != 0) { exit(sig); } 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 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; } struct nlmsg { char* pos; int nesting; struct nlattr* nested[8]; char buf[4096]; }; static void netlink_init(struct nlmsg* nlmsg, int typ, int flags, const void* data, int size) { memset(nlmsg, 0, sizeof(*nlmsg)); struct nlmsghdr* hdr = (struct nlmsghdr*)nlmsg->buf; hdr->nlmsg_type = typ; hdr->nlmsg_flags = NLM_F_REQUEST | NLM_F_ACK | flags; memcpy(hdr + 1, data, size); nlmsg->pos = (char*)(hdr + 1) + NLMSG_ALIGN(size); } static void netlink_attr(struct nlmsg* nlmsg, int typ, const void* data, int size) { struct nlattr* attr = (struct nlattr*)nlmsg->pos; attr->nla_len = sizeof(*attr) + size; attr->nla_type = typ; if (size > 0) memcpy(attr + 1, data, size); nlmsg->pos += NLMSG_ALIGN(attr->nla_len); } static void netlink_nest(struct nlmsg* nlmsg, int typ) { struct nlattr* attr = (struct nlattr*)nlmsg->pos; attr->nla_type = typ; nlmsg->pos += sizeof(*attr); nlmsg->nested[nlmsg->nesting++] = attr; } static void netlink_done(struct nlmsg* nlmsg) { struct nlattr* attr = nlmsg->nested[--nlmsg->nesting]; attr->nla_len = nlmsg->pos - (char*)attr; } static int netlink_send_ext(struct nlmsg* nlmsg, int sock, uint16_t reply_type, int* reply_len, bool dofail) { if (nlmsg->pos > nlmsg->buf + sizeof(nlmsg->buf) || nlmsg->nesting) exit(1); struct nlmsghdr* hdr = (struct nlmsghdr*)nlmsg->buf; hdr->nlmsg_len = nlmsg->pos - nlmsg->buf; struct sockaddr_nl addr; memset(&addr, 0, sizeof(addr)); addr.nl_family = AF_NETLINK; ssize_t n = sendto(sock, nlmsg->buf, hdr->nlmsg_len, 0, (struct sockaddr*)&addr, sizeof(addr)); if (n != (ssize_t)hdr->nlmsg_len) { if (dofail) exit(1); return -1; } n = recv(sock, nlmsg->buf, sizeof(nlmsg->buf), 0); if (reply_len) *reply_len = 0; if (n < 0) { if (dofail) exit(1); return -1; } if (n < (ssize_t)sizeof(struct nlmsghdr)) { errno = EINVAL; if (dofail) exit(1); return -1; } if (hdr->nlmsg_type == NLMSG_DONE) return 0; if (reply_len && hdr->nlmsg_type == reply_type) { *reply_len = n; return 0; } if (n < (ssize_t)(sizeof(struct nlmsghdr) + sizeof(struct nlmsgerr))) { errno = EINVAL; if (dofail) exit(1); return -1; } if (hdr->nlmsg_type != NLMSG_ERROR) { errno = EINVAL; if (dofail) exit(1); return -1; } errno = -((struct nlmsgerr*)(hdr + 1))->error; return -errno; } static int netlink_send(struct nlmsg* nlmsg, int sock) { return netlink_send_ext(nlmsg, sock, 0, NULL, true); } static int netlink_query_family_id(struct nlmsg* nlmsg, int sock, const char* family_name, bool dofail) { struct genlmsghdr genlhdr; memset(&genlhdr, 0, sizeof(genlhdr)); genlhdr.cmd = CTRL_CMD_GETFAMILY; netlink_init(nlmsg, GENL_ID_CTRL, 0, &genlhdr, sizeof(genlhdr)); netlink_attr(nlmsg, CTRL_ATTR_FAMILY_NAME, family_name, strnlen(family_name, GENL_NAMSIZ - 1) + 1); int n = 0; int err = netlink_send_ext(nlmsg, sock, GENL_ID_CTRL, &n, dofail); if (err < 0) { return -1; } uint16_t id = 0; struct nlattr* attr = (struct nlattr*)(nlmsg->buf + NLMSG_HDRLEN + NLMSG_ALIGN(sizeof(genlhdr))); for (; (char*)attr < nlmsg->buf + n; attr = (struct nlattr*)((char*)attr + NLMSG_ALIGN(attr->nla_len))) { if (attr->nla_type == CTRL_ATTR_FAMILY_ID) { id = *(uint16_t*)(attr + 1); break; } } if (!id) { errno = EINVAL; return -1; } recv(sock, nlmsg->buf, sizeof(nlmsg->buf), 0); return id; } static void netlink_add_device_impl(struct nlmsg* nlmsg, const char* type, const char* name, bool up) { struct ifinfomsg hdr; memset(&hdr, 0, sizeof(hdr)); if (up) hdr.ifi_flags = hdr.ifi_change = IFF_UP; netlink_init(nlmsg, RTM_NEWLINK, NLM_F_EXCL | NLM_F_CREATE, &hdr, sizeof(hdr)); if (name) netlink_attr(nlmsg, IFLA_IFNAME, name, strlen(name)); netlink_nest(nlmsg, IFLA_LINKINFO); netlink_attr(nlmsg, IFLA_INFO_KIND, type, strlen(type)); } static void netlink_device_change(struct nlmsg* nlmsg, int sock, const char* name, bool up, const char* master, const void* mac, int macsize, const char* new_name) { struct ifinfomsg hdr; memset(&hdr, 0, sizeof(hdr)); if (up) hdr.ifi_flags = hdr.ifi_change = IFF_UP; hdr.ifi_index = if_nametoindex(name); netlink_init(nlmsg, RTM_NEWLINK, 0, &hdr, sizeof(hdr)); if (new_name) netlink_attr(nlmsg, IFLA_IFNAME, new_name, strlen(new_name)); if (master) { int ifindex = if_nametoindex(master); netlink_attr(nlmsg, IFLA_MASTER, &ifindex, sizeof(ifindex)); } if (macsize) netlink_attr(nlmsg, IFLA_ADDRESS, mac, macsize); int err = netlink_send(nlmsg, sock); if (err < 0) { } } static int netlink_add_addr(struct nlmsg* nlmsg, int sock, const char* dev, const void* addr, int addrsize) { struct ifaddrmsg hdr; memset(&hdr, 0, sizeof(hdr)); hdr.ifa_family = addrsize == 4 ? AF_INET : AF_INET6; hdr.ifa_prefixlen = addrsize == 4 ? 24 : 120; hdr.ifa_scope = RT_SCOPE_UNIVERSE; hdr.ifa_index = if_nametoindex(dev); netlink_init(nlmsg, RTM_NEWADDR, NLM_F_CREATE | NLM_F_REPLACE, &hdr, sizeof(hdr)); netlink_attr(nlmsg, IFA_LOCAL, addr, addrsize); netlink_attr(nlmsg, IFA_ADDRESS, addr, addrsize); return netlink_send(nlmsg, sock); } static void netlink_add_addr4(struct nlmsg* nlmsg, int sock, const char* dev, const char* addr) { struct in_addr in_addr; inet_pton(AF_INET, addr, &in_addr); int err = netlink_add_addr(nlmsg, sock, dev, &in_addr, sizeof(in_addr)); if (err < 0) { } } static void netlink_add_addr6(struct nlmsg* nlmsg, int sock, const char* dev, const char* addr) { struct in6_addr in6_addr; inet_pton(AF_INET6, addr, &in6_addr); int err = netlink_add_addr(nlmsg, sock, dev, &in6_addr, sizeof(in6_addr)); if (err < 0) { } } static void netlink_add_neigh(struct nlmsg* nlmsg, int sock, const char* name, const void* addr, int addrsize, const void* mac, int macsize) { struct ndmsg hdr; memset(&hdr, 0, sizeof(hdr)); hdr.ndm_family = addrsize == 4 ? AF_INET : AF_INET6; hdr.ndm_ifindex = if_nametoindex(name); hdr.ndm_state = NUD_PERMANENT; netlink_init(nlmsg, RTM_NEWNEIGH, NLM_F_EXCL | NLM_F_CREATE, &hdr, sizeof(hdr)); netlink_attr(nlmsg, NDA_DST, addr, addrsize); netlink_attr(nlmsg, NDA_LLADDR, mac, macsize); int err = netlink_send(nlmsg, sock); if (err < 0) { } } static struct nlmsg nlmsg; static int tunfd = -1; #define TUN_IFACE "syz_tun" #define LOCAL_MAC 0xaaaaaaaaaaaa #define REMOTE_MAC 0xaaaaaaaaaabb #define LOCAL_IPV4 "172.20.20.170" #define REMOTE_IPV4 "172.20.20.187" #define LOCAL_IPV6 "fe80::aa" #define REMOTE_IPV6 "fe80::bb" #define IFF_NAPI 0x0010 static void initialize_tun(void) { tunfd = open("/dev/net/tun", O_RDWR | O_NONBLOCK); if (tunfd == -1) { printf("tun: can't open /dev/net/tun: please enable CONFIG_TUN=y\n"); printf("otherwise fuzzing or reproducing might not work as intended\n"); return; } const int kTunFd = 200; if (dup2(tunfd, kTunFd) < 0) exit(1); close(tunfd); tunfd = kTunFd; struct ifreq ifr; memset(&ifr, 0, sizeof(ifr)); strncpy(ifr.ifr_name, TUN_IFACE, IFNAMSIZ); ifr.ifr_flags = IFF_TAP | IFF_NO_PI; if (ioctl(tunfd, TUNSETIFF, (void*)&ifr) < 0) { exit(1); } char sysctl[64]; sprintf(sysctl, "/proc/sys/net/ipv6/conf/%s/accept_dad", TUN_IFACE); write_file(sysctl, "0"); sprintf(sysctl, "/proc/sys/net/ipv6/conf/%s/router_solicitations", TUN_IFACE); write_file(sysctl, "0"); int sock = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE); if (sock == -1) exit(1); netlink_add_addr4(&nlmsg, sock, TUN_IFACE, LOCAL_IPV4); netlink_add_addr6(&nlmsg, sock, TUN_IFACE, LOCAL_IPV6); uint64_t macaddr = REMOTE_MAC; struct in_addr in_addr; inet_pton(AF_INET, REMOTE_IPV4, &in_addr); netlink_add_neigh(&nlmsg, sock, TUN_IFACE, &in_addr, sizeof(in_addr), &macaddr, ETH_ALEN); struct in6_addr in6_addr; inet_pton(AF_INET6, REMOTE_IPV6, &in6_addr); netlink_add_neigh(&nlmsg, sock, TUN_IFACE, &in6_addr, sizeof(in6_addr), &macaddr, ETH_ALEN); macaddr = LOCAL_MAC; netlink_device_change(&nlmsg, sock, TUN_IFACE, true, 0, &macaddr, ETH_ALEN, NULL); close(sock); } #define MAX_FDS 30 #define USB_MAX_IFACE_NUM 4 #define USB_MAX_EP_NUM 32 #define USB_MAX_FDS 6 struct usb_endpoint_index { struct usb_endpoint_descriptor desc; int handle; }; struct usb_iface_index { struct usb_interface_descriptor* iface; uint8_t bInterfaceNumber; uint8_t bAlternateSetting; uint8_t bInterfaceClass; struct usb_endpoint_index eps[USB_MAX_EP_NUM]; int eps_num; }; struct usb_device_index { struct usb_device_descriptor* dev; struct usb_config_descriptor* config; uint8_t bDeviceClass; uint8_t bMaxPower; int config_length; struct usb_iface_index ifaces[USB_MAX_IFACE_NUM]; int ifaces_num; int iface_cur; }; struct usb_info { int fd; struct usb_device_index index; }; static struct usb_info usb_devices[USB_MAX_FDS]; static struct usb_device_index* lookup_usb_index(int fd) { for (int i = 0; i < USB_MAX_FDS; i++) { if (__atomic_load_n(&usb_devices[i].fd, __ATOMIC_ACQUIRE) == fd) return &usb_devices[i].index; } return NULL; } static int usb_devices_num; static bool parse_usb_descriptor(const 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->bDeviceClass = index->dev->bDeviceClass; index->bMaxPower = index->config->bMaxPower; index->config_length = length - sizeof(*index->dev); index->iface_cur = -1; 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; index->ifaces[index->ifaces_num].bInterfaceNumber = iface->bInterfaceNumber; index->ifaces[index->ifaces_num].bAlternateSetting = iface->bAlternateSetting; index->ifaces[index->ifaces_num].bInterfaceClass = iface->bInterfaceClass; index->ifaces_num++; } 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) { memcpy(&iface->eps[iface->eps_num].desc, buffer + offset, sizeof(iface->eps[iface->eps_num].desc)); iface->eps_num++; } } offset += desc_length; } return true; } static struct usb_device_index* add_usb_index(int fd, const char* dev, size_t dev_len) { int i = __atomic_fetch_add(&usb_devices_num, 1, __ATOMIC_RELAXED); if (i >= USB_MAX_FDS) return NULL; if (!parse_usb_descriptor(dev, dev_len, &usb_devices[i].index)) return NULL; __atomic_store_n(&usb_devices[i].fd, fd, __ATOMIC_RELEASE); return &usb_devices[i].index; } 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_in(int fd, const struct vusb_connect_descriptors* descs, const struct usb_ctrlrequest* ctrl, struct usb_qualifier_descriptor* qual, char** response_data, uint32_t* response_length) { struct usb_device_index* index = lookup_usb_index(fd); uint8_t str_idx; if (!index) return false; 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) { 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_data = (char*)qual; *response_length = sizeof(*qual); return true; } *response_data = descs->qual; *response_length = descs->qual_len; return true; default: break; } break; default: break; } break; default: break; } return false; } typedef bool (*lookup_connect_out_response_t)( int fd, const struct vusb_connect_descriptors* descs, const struct usb_ctrlrequest* ctrl, bool* done); static bool lookup_connect_response_out_generic( int fd, const struct vusb_connect_descriptors* descs, const struct usb_ctrlrequest* ctrl, bool* done) { switch (ctrl->bRequestType & USB_TYPE_MASK) { case USB_TYPE_STANDARD: switch (ctrl->bRequest) { case USB_REQ_SET_CONFIGURATION: *done = true; return true; default: break; } break; } return false; } #define UDC_NAME_LENGTH_MAX 128 struct usb_raw_init { __u8 driver_name[UDC_NAME_LENGTH_MAX]; __u8 device_name[UDC_NAME_LENGTH_MAX]; __u8 speed; }; enum usb_raw_event_type { USB_RAW_EVENT_INVALID = 0, USB_RAW_EVENT_CONNECT = 1, USB_RAW_EVENT_CONTROL = 2, }; struct usb_raw_event { __u32 type; __u32 length; __u8 data[0]; }; struct usb_raw_ep_io { __u16 ep; __u16 flags; __u32 length; __u8 data[0]; }; #define USB_RAW_EPS_NUM_MAX 30 #define USB_RAW_EP_NAME_MAX 16 #define USB_RAW_EP_ADDR_ANY 0xff struct usb_raw_ep_caps { __u32 type_control : 1; __u32 type_iso : 1; __u32 type_bulk : 1; __u32 type_int : 1; __u32 dir_in : 1; __u32 dir_out : 1; }; struct usb_raw_ep_limits { __u16 maxpacket_limit; __u16 max_streams; __u32 reserved; }; struct usb_raw_ep_info { __u8 name[USB_RAW_EP_NAME_MAX]; __u32 addr; struct usb_raw_ep_caps caps; struct usb_raw_ep_limits limits; }; struct usb_raw_eps_info { struct usb_raw_ep_info eps[USB_RAW_EPS_NUM_MAX]; }; #define USB_RAW_IOCTL_INIT _IOW('U', 0, struct usb_raw_init) #define USB_RAW_IOCTL_RUN _IO('U', 1) #define USB_RAW_IOCTL_EVENT_FETCH _IOR('U', 2, struct usb_raw_event) #define USB_RAW_IOCTL_EP0_WRITE _IOW('U', 3, struct usb_raw_ep_io) #define USB_RAW_IOCTL_EP0_READ _IOWR('U', 4, struct usb_raw_ep_io) #define USB_RAW_IOCTL_EP_ENABLE _IOW('U', 5, struct usb_endpoint_descriptor) #define USB_RAW_IOCTL_EP_DISABLE _IOW('U', 6, __u32) #define USB_RAW_IOCTL_EP_WRITE _IOW('U', 7, struct usb_raw_ep_io) #define USB_RAW_IOCTL_EP_READ _IOWR('U', 8, struct usb_raw_ep_io) #define USB_RAW_IOCTL_CONFIGURE _IO('U', 9) #define USB_RAW_IOCTL_VBUS_DRAW _IOW('U', 10, __u32) #define USB_RAW_IOCTL_EPS_INFO _IOR('U', 11, struct usb_raw_eps_info) #define USB_RAW_IOCTL_EP0_STALL _IO('U', 12) #define USB_RAW_IOCTL_EP_SET_HALT _IOW('U', 13, __u32) #define USB_RAW_IOCTL_EP_CLEAR_HALT _IOW('U', 14, __u32) #define USB_RAW_IOCTL_EP_SET_WEDGE _IOW('U', 15, __u32) static int usb_raw_open() { return open("/dev/raw-gadget", O_RDWR); } static int usb_raw_init(int fd, uint32_t speed, const char* driver, const char* device) { struct usb_raw_init arg; strncpy((char*)&arg.driver_name[0], driver, sizeof(arg.driver_name)); strncpy((char*)&arg.device_name[0], device, sizeof(arg.device_name)); arg.speed = speed; return ioctl(fd, USB_RAW_IOCTL_INIT, &arg); } static int usb_raw_run(int fd) { return ioctl(fd, USB_RAW_IOCTL_RUN, 0); } static int usb_raw_configure(int fd) { return ioctl(fd, USB_RAW_IOCTL_CONFIGURE, 0); } static int usb_raw_vbus_draw(int fd, uint32_t power) { return ioctl(fd, USB_RAW_IOCTL_VBUS_DRAW, power); } static int usb_raw_ep0_write(int fd, struct usb_raw_ep_io* io) { return ioctl(fd, USB_RAW_IOCTL_EP0_WRITE, io); } static int usb_raw_ep0_read(int fd, struct usb_raw_ep_io* io) { return ioctl(fd, USB_RAW_IOCTL_EP0_READ, io); } static int usb_raw_event_fetch(int fd, struct usb_raw_event* event) { return ioctl(fd, USB_RAW_IOCTL_EVENT_FETCH, event); } static int usb_raw_ep_enable(int fd, struct usb_endpoint_descriptor* desc) { return ioctl(fd, USB_RAW_IOCTL_EP_ENABLE, desc); } static int usb_raw_ep_disable(int fd, int ep) { return ioctl(fd, USB_RAW_IOCTL_EP_DISABLE, ep); } static int usb_raw_ep0_stall(int fd) { return ioctl(fd, USB_RAW_IOCTL_EP0_STALL, 0); } #define USB_MAX_PACKET_SIZE 4096 struct usb_raw_control_event { struct usb_raw_event inner; struct usb_ctrlrequest ctrl; char data[USB_MAX_PACKET_SIZE]; }; struct usb_raw_ep_io_data { struct usb_raw_ep_io inner; char data[USB_MAX_PACKET_SIZE]; }; static void set_interface(int fd, int n) { struct usb_device_index* index = lookup_usb_index(fd); if (!index) return; if (index->iface_cur >= 0 && index->iface_cur < index->ifaces_num) { for (int ep = 0; ep < index->ifaces[index->iface_cur].eps_num; ep++) { int rv = usb_raw_ep_disable( fd, index->ifaces[index->iface_cur].eps[ep].handle); if (rv < 0) { } else { } } } if (n >= 0 && n < index->ifaces_num) { for (int ep = 0; ep < index->ifaces[n].eps_num; ep++) { int rv = usb_raw_ep_enable(fd, &index->ifaces[n].eps[ep].desc); if (rv < 0) { } else { index->ifaces[n].eps[ep].handle = rv; } } index->iface_cur = n; } } static int configure_device(int fd) { struct usb_device_index* index = lookup_usb_index(fd); if (!index) return -1; int rv = usb_raw_vbus_draw(fd, index->bMaxPower); if (rv < 0) { return rv; } rv = usb_raw_configure(fd); if (rv < 0) { return rv; } set_interface(fd, 0); return 0; } static volatile long syz_usb_connect_impl(uint64_t speed, uint64_t dev_len, const char* dev, const struct vusb_connect_descriptors* descs, lookup_connect_out_response_t lookup_connect_response_out) { if (!dev) { return -1; } int fd = usb_raw_open(); if (fd < 0) { return fd; } if (fd >= MAX_FDS) { close(fd); return -1; } struct usb_device_index* index = add_usb_index(fd, dev, dev_len); if (!index) { return -1; } char device[32]; sprintf(&device[0], "dummy_udc.%llu", procid); int rv = usb_raw_init(fd, speed, "dummy_udc", &device[0]); if (rv < 0) { return rv; } rv = usb_raw_run(fd); if (rv < 0) { return rv; } bool done = false; while (!done) { struct usb_raw_control_event event; event.inner.type = 0; event.inner.length = sizeof(event.ctrl); rv = usb_raw_event_fetch(fd, (struct usb_raw_event*)&event); if (rv < 0) { return rv; } if (event.inner.type != USB_RAW_EVENT_CONTROL) continue; char* response_data = NULL; uint32_t response_length = 0; struct usb_qualifier_descriptor qual; if (event.ctrl.bRequestType & USB_DIR_IN) { if (!lookup_connect_response_in(fd, descs, &event.ctrl, &qual, &response_data, &response_length)) { usb_raw_ep0_stall(fd); continue; } } else { if (!lookup_connect_response_out(fd, descs, &event.ctrl, &done)) { usb_raw_ep0_stall(fd); continue; } response_data = NULL; response_length = event.ctrl.wLength; } if ((event.ctrl.bRequestType & USB_TYPE_MASK) == USB_TYPE_STANDARD && event.ctrl.bRequest == USB_REQ_SET_CONFIGURATION) { rv = configure_device(fd); if (rv < 0) { return rv; } } struct usb_raw_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_raw_ep0_write(fd, (struct usb_raw_ep_io*)&response); } else { rv = usb_raw_ep0_read(fd, (struct usb_raw_ep_io*)&response); } if (rv < 0) { return rv; } } sleep_ms(200); return fd; } 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; const char* dev = (const char*)a2; const struct vusb_connect_descriptors* descs = (const struct vusb_connect_descriptors*)a3; return syz_usb_connect_impl(speed, dev_len, dev, descs, &lookup_connect_response_out_generic); } #define BTPROTO_HCI 1 #define ACL_LINK 1 #define SCAN_PAGE 2 typedef struct { uint8_t b[6]; } __attribute__((packed)) bdaddr_t; #define HCI_COMMAND_PKT 1 #define HCI_EVENT_PKT 4 #define HCI_VENDOR_PKT 0xff struct hci_command_hdr { uint16_t opcode; uint8_t plen; } __attribute__((packed)); struct hci_event_hdr { uint8_t evt; uint8_t plen; } __attribute__((packed)); #define HCI_EV_CONN_COMPLETE 0x03 struct hci_ev_conn_complete { uint8_t status; uint16_t handle; bdaddr_t bdaddr; uint8_t link_type; uint8_t encr_mode; } __attribute__((packed)); #define HCI_EV_CONN_REQUEST 0x04 struct hci_ev_conn_request { bdaddr_t bdaddr; uint8_t dev_class[3]; uint8_t link_type; } __attribute__((packed)); #define HCI_EV_REMOTE_FEATURES 0x0b struct hci_ev_remote_features { uint8_t status; uint16_t handle; uint8_t features[8]; } __attribute__((packed)); #define HCI_EV_CMD_COMPLETE 0x0e struct hci_ev_cmd_complete { uint8_t ncmd; uint16_t opcode; } __attribute__((packed)); #define HCI_OP_WRITE_SCAN_ENABLE 0x0c1a #define HCI_OP_READ_BUFFER_SIZE 0x1005 struct hci_rp_read_buffer_size { uint8_t status; uint16_t acl_mtu; uint8_t sco_mtu; uint16_t acl_max_pkt; uint16_t sco_max_pkt; } __attribute__((packed)); #define HCI_OP_READ_BD_ADDR 0x1009 struct hci_rp_read_bd_addr { uint8_t status; bdaddr_t bdaddr; } __attribute__((packed)); #define HCI_EV_LE_META 0x3e struct hci_ev_le_meta { uint8_t subevent; } __attribute__((packed)); #define HCI_EV_LE_CONN_COMPLETE 0x01 struct hci_ev_le_conn_complete { uint8_t status; uint16_t handle; uint8_t role; uint8_t bdaddr_type; bdaddr_t bdaddr; uint16_t interval; uint16_t latency; uint16_t supervision_timeout; uint8_t clk_accurancy; } __attribute__((packed)); struct hci_dev_req { uint16_t dev_id; uint32_t dev_opt; }; struct vhci_vendor_pkt_request { uint8_t type; uint8_t opcode; } __attribute__((packed)); struct vhci_pkt { uint8_t type; union { struct { uint8_t opcode; uint16_t id; } __attribute__((packed)) vendor_pkt; struct hci_command_hdr command_hdr; }; } __attribute__((packed)); #define HCIDEVUP _IOW('H', 201, int) #define HCISETSCAN _IOW('H', 221, int) static int vhci_fd = -1; static void rfkill_unblock_all() { int fd = open("/dev/rfkill", O_WRONLY); if (fd < 0) exit(1); struct rfkill_event event = {0}; event.idx = 0; event.type = RFKILL_TYPE_ALL; event.op = RFKILL_OP_CHANGE_ALL; event.soft = 0; event.hard = 0; if (write(fd, &event, sizeof(event)) < 0) exit(1); close(fd); } static void hci_send_event_packet(int fd, uint8_t evt, void* data, size_t data_len) { struct iovec iv[3]; struct hci_event_hdr hdr; hdr.evt = evt; hdr.plen = data_len; uint8_t type = HCI_EVENT_PKT; iv[0].iov_base = &type; iv[0].iov_len = sizeof(type); iv[1].iov_base = &hdr; iv[1].iov_len = sizeof(hdr); iv[2].iov_base = data; iv[2].iov_len = data_len; if (writev(fd, iv, sizeof(iv) / sizeof(struct iovec)) < 0) exit(1); } static void hci_send_event_cmd_complete(int fd, uint16_t opcode, void* data, size_t data_len) { struct iovec iv[4]; struct hci_event_hdr hdr; hdr.evt = HCI_EV_CMD_COMPLETE; hdr.plen = sizeof(struct hci_ev_cmd_complete) + data_len; struct hci_ev_cmd_complete evt_hdr; evt_hdr.ncmd = 1; evt_hdr.opcode = opcode; uint8_t type = HCI_EVENT_PKT; iv[0].iov_base = &type; iv[0].iov_len = sizeof(type); iv[1].iov_base = &hdr; iv[1].iov_len = sizeof(hdr); iv[2].iov_base = &evt_hdr; iv[2].iov_len = sizeof(evt_hdr); iv[3].iov_base = data; iv[3].iov_len = data_len; if (writev(fd, iv, sizeof(iv) / sizeof(struct iovec)) < 0) exit(1); } static bool process_command_pkt(int fd, char* buf, ssize_t buf_size) { struct hci_command_hdr* hdr = (struct hci_command_hdr*)buf; if (buf_size < (ssize_t)sizeof(struct hci_command_hdr) || hdr->plen != buf_size - sizeof(struct hci_command_hdr)) exit(1); switch (hdr->opcode) { case HCI_OP_WRITE_SCAN_ENABLE: { uint8_t status = 0; hci_send_event_cmd_complete(fd, hdr->opcode, &status, sizeof(status)); return true; } case HCI_OP_READ_BD_ADDR: { struct hci_rp_read_bd_addr rp = {0}; rp.status = 0; memset(&rp.bdaddr, 0xaa, 6); hci_send_event_cmd_complete(fd, hdr->opcode, &rp, sizeof(rp)); return false; } case HCI_OP_READ_BUFFER_SIZE: { struct hci_rp_read_buffer_size rp = {0}; rp.status = 0; rp.acl_mtu = 1021; rp.sco_mtu = 96; rp.acl_max_pkt = 4; rp.sco_max_pkt = 6; hci_send_event_cmd_complete(fd, hdr->opcode, &rp, sizeof(rp)); return false; } } char dummy[0xf9] = {0}; hci_send_event_cmd_complete(fd, hdr->opcode, dummy, sizeof(dummy)); return false; } static void* event_thread(void* arg) { while (1) { char buf[1024] = {0}; ssize_t buf_size = read(vhci_fd, buf, sizeof(buf)); if (buf_size < 0) exit(1); if (buf_size > 0 && buf[0] == HCI_COMMAND_PKT) { if (process_command_pkt(vhci_fd, buf + 1, buf_size - 1)) break; } } return NULL; } #define HCI_HANDLE_1 200 #define HCI_HANDLE_2 201 #define HCI_PRIMARY 0 #define HCI_OP_RESET 0x0c03 static void initialize_vhci() { int hci_sock = socket(AF_BLUETOOTH, SOCK_RAW, BTPROTO_HCI); if (hci_sock < 0) exit(1); vhci_fd = open("/dev/vhci", O_RDWR); if (vhci_fd == -1) exit(1); const int kVhciFd = 202; if (dup2(vhci_fd, kVhciFd) < 0) exit(1); close(vhci_fd); vhci_fd = kVhciFd; struct vhci_vendor_pkt_request vendor_pkt_req = {HCI_VENDOR_PKT, HCI_PRIMARY}; if (write(vhci_fd, &vendor_pkt_req, sizeof(vendor_pkt_req)) != sizeof(vendor_pkt_req)) exit(1); struct vhci_pkt vhci_pkt; if (read(vhci_fd, &vhci_pkt, sizeof(vhci_pkt)) != sizeof(vhci_pkt)) exit(1); if (vhci_pkt.type == HCI_COMMAND_PKT && vhci_pkt.command_hdr.opcode == HCI_OP_RESET) { char response[1] = {0}; hci_send_event_cmd_complete(vhci_fd, HCI_OP_RESET, response, sizeof(response)); if (read(vhci_fd, &vhci_pkt, sizeof(vhci_pkt)) != sizeof(vhci_pkt)) exit(1); } if (vhci_pkt.type != HCI_VENDOR_PKT) exit(1); int dev_id = vhci_pkt.vendor_pkt.id; pthread_t th; if (pthread_create(&th, NULL, event_thread, NULL)) exit(1); int ret = ioctl(hci_sock, HCIDEVUP, dev_id); if (ret) { if (errno == ERFKILL) { rfkill_unblock_all(); ret = ioctl(hci_sock, HCIDEVUP, dev_id); } if (ret && errno != EALREADY) exit(1); } struct hci_dev_req dr = {0}; dr.dev_id = dev_id; dr.dev_opt = SCAN_PAGE; if (ioctl(hci_sock, HCISETSCAN, &dr)) exit(1); struct hci_ev_conn_request request; memset(&request, 0, sizeof(request)); memset(&request.bdaddr, 0xaa, 6); *(uint8_t*)&request.bdaddr.b[5] = 0x10; request.link_type = ACL_LINK; hci_send_event_packet(vhci_fd, HCI_EV_CONN_REQUEST, &request, sizeof(request)); struct hci_ev_conn_complete complete; memset(&complete, 0, sizeof(complete)); complete.status = 0; complete.handle = HCI_HANDLE_1; memset(&complete.bdaddr, 0xaa, 6); *(uint8_t*)&complete.bdaddr.b[5] = 0x10; complete.link_type = ACL_LINK; complete.encr_mode = 0; hci_send_event_packet(vhci_fd, HCI_EV_CONN_COMPLETE, &complete, sizeof(complete)); struct hci_ev_remote_features features; memset(&features, 0, sizeof(features)); features.status = 0; features.handle = HCI_HANDLE_1; hci_send_event_packet(vhci_fd, HCI_EV_REMOTE_FEATURES, &features, sizeof(features)); struct { struct hci_ev_le_meta le_meta; struct hci_ev_le_conn_complete le_conn; } le_conn; memset(&le_conn, 0, sizeof(le_conn)); le_conn.le_meta.subevent = HCI_EV_LE_CONN_COMPLETE; memset(&le_conn.le_conn.bdaddr, 0xaa, 6); *(uint8_t*)&le_conn.le_conn.bdaddr.b[5] = 0x11; le_conn.le_conn.role = 1; le_conn.le_conn.handle = HCI_HANDLE_2; hci_send_event_packet(vhci_fd, HCI_EV_LE_META, &le_conn, sizeof(le_conn)); pthread_join(th, NULL); close(hci_sock); } static void setup_common() { if (mount(0, "/sys/fs/fuse/connections", "fusectl", 0, 0)) { } } static void setup_binderfs() { if (mkdir("/dev/binderfs", 0777)) { } if (mount("binder", "/dev/binderfs", "binder", 0, NULL)) { } } static void loop(); static void sandbox_common() { prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0); setsid(); struct rlimit rlim; rlim.rlim_cur = rlim.rlim_max = (200 << 20); setrlimit(RLIMIT_AS, &rlim); rlim.rlim_cur = rlim.rlim_max = 32 << 20; setrlimit(RLIMIT_MEMLOCK, &rlim); rlim.rlim_cur = rlim.rlim_max = 136 << 20; setrlimit(RLIMIT_FSIZE, &rlim); rlim.rlim_cur = rlim.rlim_max = 1 << 20; setrlimit(RLIMIT_STACK, &rlim); rlim.rlim_cur = rlim.rlim_max = 128 << 20; setrlimit(RLIMIT_CORE, &rlim); rlim.rlim_cur = rlim.rlim_max = 256; setrlimit(RLIMIT_NOFILE, &rlim); if (unshare(CLONE_NEWNS)) { } if (mount(NULL, "/", NULL, MS_REC | MS_PRIVATE, NULL)) { } if (unshare(CLONE_NEWIPC)) { } if (unshare(0x02000000)) { } if (unshare(CLONE_NEWUTS)) { } if (unshare(CLONE_SYSVSEM)) { } typedef struct { const char* name; const char* value; } sysctl_t; static const sysctl_t sysctls[] = { {"/proc/sys/kernel/shmmax", "16777216"}, {"/proc/sys/kernel/shmall", "536870912"}, {"/proc/sys/kernel/shmmni", "1024"}, {"/proc/sys/kernel/msgmax", "8192"}, {"/proc/sys/kernel/msgmni", "1024"}, {"/proc/sys/kernel/msgmnb", "1024"}, {"/proc/sys/kernel/sem", "1024 1048576 500 1024"}, }; unsigned i; for (i = 0; i < sizeof(sysctls) / sizeof(sysctls[0]); i++) write_file(sysctls[i].name, sysctls[i].value); } static int wait_for_loop(int pid) { if (pid < 0) exit(1); int status = 0; while (waitpid(-1, &status, __WALL) != pid) { } return WEXITSTATUS(status); } static void drop_caps(void) { struct __user_cap_header_struct cap_hdr = {}; struct __user_cap_data_struct cap_data[2] = {}; cap_hdr.version = _LINUX_CAPABILITY_VERSION_3; cap_hdr.pid = getpid(); if (syscall(SYS_capget, &cap_hdr, &cap_data)) exit(1); const int drop = (1 << CAP_SYS_PTRACE) | (1 << CAP_SYS_NICE); cap_data[0].effective &= ~drop; cap_data[0].permitted &= ~drop; cap_data[0].inheritable &= ~drop; if (syscall(SYS_capset, &cap_hdr, &cap_data)) exit(1); } static int do_sandbox_none(void) { if (unshare(CLONE_NEWPID)) { } int pid = fork(); if (pid != 0) return wait_for_loop(pid); setup_common(); initialize_vhci(); sandbox_common(); drop_caps(); if (unshare(CLONE_NEWNET)) { } write_file("/proc/sys/net/ipv4/ping_group_range", "0 65535"); initialize_tun(); setup_binderfs(); loop(); exit(1); } static void close_fds() { for (int fd = 3; fd < MAX_FDS; fd++) close(fd); } static void setup_binfmt_misc() { if (mount(0, "/proc/sys/fs/binfmt_misc", "binfmt_misc", 0, 0)) { } write_file("/proc/sys/fs/binfmt_misc/register", ":syz0:M:0:\x01::./file0:"); write_file("/proc/sys/fs/binfmt_misc/register", ":syz1:M:1:\x02::./file0:POC"); } static void setup_usb() { if (chmod("/dev/raw-gadget", 0666)) exit(1); } static void setup_sysctl() { char mypid[32]; snprintf(mypid, sizeof(mypid), "%d", getpid()); struct { const char* name; const char* data; } files[] = { {"/sys/kernel/debug/x86/nmi_longest_ns", "10000000000"}, {"/proc/sys/kernel/hung_task_check_interval_secs", "20"}, {"/proc/sys/net/core/bpf_jit_kallsyms", "1"}, {"/proc/sys/net/core/bpf_jit_harden", "0"}, {"/proc/sys/kernel/kptr_restrict", "0"}, {"/proc/sys/kernel/softlockup_all_cpu_backtrace", "1"}, {"/proc/sys/fs/mount-max", "100"}, {"/proc/sys/vm/oom_dump_tasks", "0"}, {"/proc/sys/debug/exception-trace", "0"}, {"/proc/sys/kernel/printk", "7 4 1 3"}, {"/proc/sys/kernel/keys/gc_delay", "1"}, {"/proc/sys/vm/oom_kill_allocating_task", "1"}, {"/proc/sys/kernel/ctrl-alt-del", "0"}, {"/proc/sys/kernel/cad_pid", mypid}, }; for (size_t i = 0; i < sizeof(files) / sizeof(files[0]); i++) { if (!write_file(files[i].name, files[i].data)) printf("write to %s failed: %s\n", files[i].name, strerror(errno)); } } #define NL802154_CMD_SET_SHORT_ADDR 11 #define NL802154_ATTR_IFINDEX 3 #define NL802154_ATTR_SHORT_ADDR 10 static void setup_802154() { int sock_route = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE); if (sock_route == -1) exit(1); int sock_generic = socket(AF_NETLINK, SOCK_RAW, NETLINK_GENERIC); if (sock_generic < 0) exit(1); int nl802154_family_id = netlink_query_family_id(&nlmsg, sock_generic, "nl802154", true); for (int i = 0; i < 2; i++) { char devname[] = "wpan0"; devname[strlen(devname) - 1] += i; uint64_t hwaddr = 0xaaaaaaaaaaaa0002 + (i << 8); uint16_t shortaddr = 0xaaa0 + i; int ifindex = if_nametoindex(devname); struct genlmsghdr genlhdr; memset(&genlhdr, 0, sizeof(genlhdr)); genlhdr.cmd = NL802154_CMD_SET_SHORT_ADDR; netlink_init(&nlmsg, nl802154_family_id, 0, &genlhdr, sizeof(genlhdr)); netlink_attr(&nlmsg, NL802154_ATTR_IFINDEX, &ifindex, sizeof(ifindex)); netlink_attr(&nlmsg, NL802154_ATTR_SHORT_ADDR, &shortaddr, sizeof(shortaddr)); int err = netlink_send(&nlmsg, sock_generic); if (err < 0) { } netlink_device_change(&nlmsg, sock_route, devname, true, 0, &hwaddr, sizeof(hwaddr), 0); if (i == 0) { netlink_add_device_impl(&nlmsg, "lowpan", "lowpan0", false); netlink_done(&nlmsg); netlink_attr(&nlmsg, IFLA_LINK, &ifindex, sizeof(ifindex)); int err = netlink_send(&nlmsg, sock_route); if (err < 0) { } } } close(sock_route); close(sock_generic); } void loop(void) { NONFAILING( memcpy((void*)0x20000000, "\x12\x01\x00\x00\x36\xee\x38\x08\xd3\x0b\x55\x0d\x6a\x69\x40\x00" "\x00\x01\x09\x02\x46\x00\x01\x00\x00\x00\x00\x09\x04\x00\x00\x00" "\x0e\x01\x00\x00\x08\x24\x03\xff\x01\x03\x00\x00\x09\x24\x03", 47)); NONFAILING(*(uint8_t*)0x2000002f = 0); NONFAILING(*(uint16_t*)0x20000030 = -1); NONFAILING(syz_usb_connect(0, 0x58, 0x20000000, 0)); close_fds(); } 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_binfmt_misc(); setup_usb(); setup_802154(); install_segv_handler(); use_temporary_dir(); do_sandbox_none(); return 0; }