// https://syzkaller.appspot.com/bug?id=1c0bea493ac82d5f3642dd27710c4492463efa83 // 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 #ifndef __NR_bpf #define __NR_bpf 321 #endif 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 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; } #define BITMASK(bf_off, bf_len) (((1ull << (bf_len)) - 1) << (bf_off)) #define STORE_BY_BITMASK(type, htobe, addr, val, bf_off, bf_len) \ *(type*)(addr) = \ htobe((htobe(*(type*)(addr)) & ~BITMASK((bf_off), (bf_len))) | \ (((type)(val) << (bf_off)) & BITMASK((bf_off), (bf_len)))) 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 struct nlmsg nlmsg; #define MAX_FDS 30 #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_gadgetfs(); static void setup_binderfs(); static void setup_fusectl(); static void sandbox_common_mount_tmpfs(void) { write_file("/proc/sys/fs/mount-max", "100000"); 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("syz-proc", "./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); if (mount("/sys/kernel/debug", "./syz-tmp/newroot/sys/kernel/debug", NULL, bind_mount_flags, NULL) && errno != ENOENT) exit(1); if (mount("/sys/fs/smackfs", "./syz-tmp/newroot/sys/fs/smackfs", NULL, bind_mount_flags, NULL) && errno != ENOENT) exit(1); if (mount("/proc/sys/fs/binfmt_misc", "./syz-tmp/newroot/proc/sys/fs/binfmt_misc", NULL, bind_mount_flags, NULL) && errno != ENOENT) exit(1); if (mkdir("./syz-tmp/newroot/syz-inputs", 0700)) exit(1); if (mount("/syz-inputs", "./syz-tmp/newroot/syz-inputs", NULL, bind_mount_flags | MS_RDONLY, NULL) && errno != ENOENT) exit(1); 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); setup_gadgetfs(); setup_binderfs(); setup_fusectl(); } static void setup_gadgetfs() { if (mkdir("/dev/gadgetfs", 0777)) { } if (mount("gadgetfs", "/dev/gadgetfs", "gadgetfs", 0, NULL)) { } } static void setup_fusectl() { 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)) { } if (symlink("/dev/binderfs", "./binderfs")) { } } static void loop(); static void sandbox_common() { prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0); if (getppid() == 1) exit(1); 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); initialize_vhci(); sandbox_common(); drop_caps(); if (unshare(CLONE_NEWNET)) { } write_file("/proc/sys/net/ipv4/ping_group_range", "0 65535"); sandbox_common_mount_tmpfs(); loop(); exit(1); } static void kill_and_wait(int pid, int* status) { kill(-pid, SIGKILL); kill(pid, SIGKILL); for (int i = 0; i < 100; i++) { if (waitpid(-1, status, WNOHANG | __WALL) == pid) return; usleep(1000); } DIR* dir = opendir("/sys/fs/fuse/connections"); if (dir) { for (;;) { struct dirent* ent = readdir(dir); if (!ent) break; if (strcmp(ent->d_name, ".") == 0 || strcmp(ent->d_name, "..") == 0) continue; char abort[300]; snprintf(abort, sizeof(abort), "/sys/fs/fuse/connections/%s/abort", ent->d_name); int fd = open(abort, O_WRONLY); if (fd == -1) { continue; } if (write(fd, abort, 1) < 0) { } close(fd); } closedir(dir); } else { } while (waitpid(-1, status, __WALL) != pid) { } } static void setup_test() { prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0); setpgrp(); write_file("/proc/self/oom_score_adj", "1000"); } static void close_fds() { for (int fd = 3; fd < MAX_FDS; fd++) close(fd); } #define NL802154_CMD_SET_SHORT_ADDR 11 #define NL802154_ATTR_IFINDEX 3 #define NL802154_ATTR_SHORT_ADDR 10 static const char* setup_802154() { const char* error = NULL; int sock_generic = -1; int sock_route = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE); if (sock_route == -1) { error = "socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE) failed"; goto fail; } sock_generic = socket(AF_NETLINK, SOCK_RAW, NETLINK_GENERIC); if (sock_generic == -1) { error = "socket(AF_NETLINK, SOCK_RAW, NETLINK_GENERIC) failed"; goto fail; } { int nl802154_family_id = netlink_query_family_id(&nlmsg, sock_generic, "nl802154", true); if (nl802154_family_id < 0) { error = "netlink_query_family_id failed"; goto fail; } 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)); if (netlink_send(&nlmsg, sock_generic) < 0) { error = "NL802154_CMD_SET_SHORT_ADDR failed"; goto fail; } 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)); if (netlink_send(&nlmsg, sock_route) < 0) { error = "netlink: adding device lowpan0 type lowpan link wpan0"; goto fail; } } } } fail: close(sock_route); close(sock_generic); return error; } static void execute_one(void); #define WAIT_FLAGS __WALL static void loop(void) { int iter = 0; for (;; iter++) { int pid = fork(); if (pid < 0) exit(1); if (pid == 0) { setup_test(); execute_one(); close_fds(); exit(0); } int status = 0; uint64_t start = current_time_ms(); for (;;) { sleep_ms(10); if (waitpid(-1, &status, WNOHANG | WAIT_FLAGS) == pid) break; if (current_time_ms() - start < 5000) continue; kill_and_wait(pid, &status); break; } } } uint64_t r[2] = {0xffffffffffffffff, 0xffffffffffffffff}; void execute_one(void) { intptr_t res = 0; if (write(1, "executing program\n", sizeof("executing program\n") - 1)) { } // bpf$BPF_PROG_RAW_TRACEPOINT_LOAD arguments: [ // cmd: const = 0x5 (8 bytes) // arg: ptr[in, bpf_prog_t[flags[bpf_raw_tracepoint_prog_types, int32], // const[0, int32], const[0, int32], const[0, int32]]] { // bpf_prog_t[flags[bpf_raw_tracepoint_prog_types, int32], const[0, // int32], const[0, int32], const[0, int32]] { // type: bpf_raw_tracepoint_prog_types = 0x18 (4 bytes) // ninsn: bytesize8 = 0x5 (4 bytes) // insns: ptr[inout, array[ANYUNION]] { // array[ANYUNION] { // union ANYUNION { // ANYBLOB: buffer: {18 01 00 00 21 00 00 00 00 00 00 00 3b 81 00 // 00 85 00 00 00 6d 00 00 00 85 00 00 00 50 00 00 00 95} (length // 0x21) // } // } // } // license: ptr[in, buffer] { // buffer: {73 79 7a 6b 61 6c 6c 65 72 00} (length 0xa) // } // loglev: int32 = 0x0 (4 bytes) // logsize: len = 0x0 (4 bytes) // log: nil // kern_version: bpf_kern_version = 0x0 (4 bytes) // flags: bpf_prog_load_flags = 0x4 (4 bytes) // prog_name: buffer: {00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00} // (length 0x10) prog_ifindex: ifindex (resource) expected_attach_type: // const = 0x2 (4 bytes) btf_fd: fd_btf (resource) func_info_rec_size: // const = 0x8 (4 bytes) func_info: nil func_info_cnt: len = 0x0 (4 // bytes) line_info_rec_size: const = 0x10 (4 bytes) line_info: nil // line_info_cnt: len = 0x0 (4 bytes) // attach_btf_id: const = 0x0 (4 bytes) // attach_prog_fd: const = 0x0 (4 bytes) // core_relo_cnt: len = 0x0 (4 bytes) // fd_array: nil // core_relos: nil // core_relo_rec_size: const = 0x10 (4 bytes) // log_true_size: int32 = 0x0 (4 bytes) // prog_token_fd: union // _bpf_prog_t[flags[bpf_raw_tracepoint_prog_types, int32], const[0, // int32], const[0, int32], const[0, int32]]_prog_token_fd_wrapper { // void: buffer: {} (length 0x0) // } // pad: union _bpf_prog_t[flags[bpf_raw_tracepoint_prog_types, int32], // const[0, int32], const[0, int32], const[0, int32]]_pad_wrapper { // value: const = 0x0 (4 bytes) // } // } // } // size: len = 0x94 (8 bytes) // ] // returns fd_bpf_prog_raw_tracepoint NONFAILING(*(uint32_t*)0x200000000180 = 0x18); NONFAILING(*(uint32_t*)0x200000000184 = 5); NONFAILING(*(uint64_t*)0x200000000188 = 0x200000000480); NONFAILING(memcpy( (void*)0x200000000480, "\x18\x01\x00\x00\x21\x00\x00\x00\x00\x00\x00\x00\x3b\x81\x00\x00\x85\x00" "\x00\x00\x6d\x00\x00\x00\x85\x00\x00\x00\x50\x00\x00\x00\x95", 33)); NONFAILING(*(uint64_t*)0x200000000190 = 0x200000000040); NONFAILING(memcpy((void*)0x200000000040, "syzkaller\000", 10)); NONFAILING(*(uint32_t*)0x200000000198 = 0); NONFAILING(*(uint32_t*)0x20000000019c = 0); NONFAILING(*(uint64_t*)0x2000000001a0 = 0); NONFAILING(*(uint32_t*)0x2000000001a8 = 0); NONFAILING(*(uint32_t*)0x2000000001ac = 4); NONFAILING(memset((void*)0x2000000001b0, 0, 16)); NONFAILING(*(uint32_t*)0x2000000001c0 = 0); NONFAILING(*(uint32_t*)0x2000000001c4 = 2); NONFAILING(*(uint32_t*)0x2000000001c8 = -1); NONFAILING(*(uint32_t*)0x2000000001cc = 8); NONFAILING(*(uint64_t*)0x2000000001d0 = 0); NONFAILING(*(uint32_t*)0x2000000001d8 = 0); NONFAILING(*(uint32_t*)0x2000000001dc = 0x10); NONFAILING(*(uint64_t*)0x2000000001e0 = 0); NONFAILING(*(uint32_t*)0x2000000001e8 = 0); NONFAILING(*(uint32_t*)0x2000000001ec = 0); NONFAILING(*(uint32_t*)0x2000000001f0 = 0); NONFAILING(*(uint32_t*)0x2000000001f4 = 0); NONFAILING(*(uint64_t*)0x2000000001f8 = 0); NONFAILING(*(uint64_t*)0x200000000200 = 0); NONFAILING(*(uint32_t*)0x200000000208 = 0x10); NONFAILING(*(uint32_t*)0x20000000020c = 0); NONFAILING(*(uint32_t*)0x200000000210 = 0); res = syscall(__NR_bpf, /*cmd=*/5ul, /*arg=*/0x200000000180ul, /*size=*/0x94ul); if (res != -1) r[0] = res; // close arguments: [ // fd: fd (resource) // ] syscall(__NR_close, /*fd=*/r[0]); // bpf$PROG_LOAD_XDP arguments: [ // cmd: const = 0x5 (8 bytes) // arg: ptr[in, bpf_prog_t[const[BPF_PROG_TYPE_XDP, int32], const[BPF_XDP, // int32], const[0, int32], const[0, int32]]] { // bpf_prog_t[const[BPF_PROG_TYPE_XDP, int32], const[BPF_XDP, int32], // const[0, int32], const[0, int32]] { // type: const = 0x18 (4 bytes) // ninsn: bytesize8 = 0x6 (4 bytes) // insns: ptr[in, bpf_instructions] { // union bpf_instructions { // framed: bpf_framed_program { // initr0: bpf_insn_init_r0 { // code: const = 0x18 (1 bytes) // dst: const = 0x0 (0 bytes) // src: const = 0x0 (1 bytes) // off: const = 0x0 (2 bytes) // imm: int32 = 0x0 (4 bytes) // code2: const = 0x0 (1 bytes) // regs2: const = 0x0 (1 bytes) // off2: const = 0x0 (2 bytes) // imm2: int32 = 0x80ffffff (4 bytes) // } // body: array[bpf_insn] { // union bpf_insn { // jmp: bpf_insn_jmp { // code_class: const = 0x5 (0 bytes) // code_s: int8 = 0x0 (0 bytes) // code_op: bpf_jmp_op = 0x849aee721dcc84be (1 bytes) // dst: bpf_reg = 0x0 (0 bytes) // src: bpf_reg = 0x0 (1 bytes) // off: bpf_insn_offsets = 0x2 (2 bytes) // imm: bpf_insn_immediates = 0x0 (4 bytes) // } // } // union bpf_insn { // jmp: bpf_insn_jmp { // code_class: const = 0x5 (0 bytes) // code_s: int8 = 0x0 (0 bytes) // code_op: bpf_jmp_op = 0xc (1 bytes) // dst: bpf_reg = 0x0 (0 bytes) // src: bpf_reg = 0x0 (1 bytes) // off: bpf_insn_offsets = 0xfffffffffffffffc (2 bytes) // imm: bpf_insn_immediates = 0x0 (4 bytes) // } // } // union bpf_insn { // jmp: bpf_insn_jmp { // code_class: const = 0x5 (0 bytes) // code_s: int8 = 0x0 (0 bytes) // code_op: bpf_jmp_op = 0x8 (1 bytes) // dst: bpf_reg = 0x0 (0 bytes) // src: bpf_reg = 0x0 (1 bytes) // off: bpf_insn_offsets = 0xfffffffffffffffe (2 bytes) // imm: bpf_insn_immediates = 0xd1 (4 bytes) // } // } // } // exit: bpf_insn_exit { // code: const = 0x95 (1 bytes) // regs: const = 0x0 (1 bytes) // off: const = 0x0 (2 bytes) // imm: const = 0x0 (4 bytes) // } // } // } // } // license: ptr[in, buffer] { // buffer: {47 50 4c 00} (length 0x4) // } // loglev: int32 = 0x5 (4 bytes) // logsize: len = 0x0 (4 bytes) // log: nil // kern_version: bpf_kern_version = 0x0 (4 bytes) // flags: bpf_prog_load_flags = 0x8 (4 bytes) // prog_name: buffer: {00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00} // (length 0x10) prog_ifindex: ifindex (resource) expected_attach_type: // const = 0x25 (4 bytes) btf_fd: fd_btf (resource) func_info_rec_size: // const = 0x8 (4 bytes) func_info: nil func_info_cnt: len = 0x0 (4 // bytes) line_info_rec_size: const = 0x10 (4 bytes) line_info: nil // line_info_cnt: len = 0x0 (4 bytes) // attach_btf_id: const = 0x0 (4 bytes) // attach_prog_fd: const = 0x0 (4 bytes) // core_relo_cnt: len = 0x0 (4 bytes) // fd_array: nil // core_relos: nil // core_relo_rec_size: const = 0x10 (4 bytes) // log_true_size: int32 = 0x4 (4 bytes) // prog_token_fd: union _bpf_prog_t[const[BPF_PROG_TYPE_XDP, int32], // const[BPF_XDP, int32], const[0, int32], const[0, // int32]]_prog_token_fd_wrapper { // void: buffer: {} (length 0x0) // } // pad: union _bpf_prog_t[const[BPF_PROG_TYPE_XDP, int32], // const[BPF_XDP, int32], const[0, int32], const[0, int32]]_pad_wrapper // { // value: const = 0x0 (4 bytes) // } // } // } // size: len = 0x94 (8 bytes) // ] // returns fd_bpf_prog_xdp NONFAILING(*(uint32_t*)0x200000000100 = 0x18); NONFAILING(*(uint32_t*)0x200000000104 = 6); NONFAILING(*(uint64_t*)0x200000000108 = 0x2000000001c0); NONFAILING(*(uint8_t*)0x2000000001c0 = 0x18); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x2000000001c1, 0, 0, 4)); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x2000000001c1, 0, 4, 4)); NONFAILING(*(uint16_t*)0x2000000001c2 = 0); NONFAILING(*(uint32_t*)0x2000000001c4 = 0); NONFAILING(*(uint8_t*)0x2000000001c8 = 0); NONFAILING(*(uint8_t*)0x2000000001c9 = 0); NONFAILING(*(uint16_t*)0x2000000001ca = 0); NONFAILING(*(uint32_t*)0x2000000001cc = 0x80ffffff); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x2000000001d0, 5, 0, 3)); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x2000000001d0, 0, 3, 1)); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x2000000001d0, 0xbe, 4, 4)); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x2000000001d1, 0, 0, 4)); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x2000000001d1, 0, 4, 4)); NONFAILING(*(uint16_t*)0x2000000001d2 = 2); NONFAILING(*(uint32_t*)0x2000000001d4 = 0); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x2000000001d8, 5, 0, 3)); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x2000000001d8, 0, 3, 1)); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x2000000001d8, 0xc, 4, 4)); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x2000000001d9, 0, 0, 4)); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x2000000001d9, 0, 4, 4)); NONFAILING(*(uint16_t*)0x2000000001da = 0xfffc); NONFAILING(*(uint32_t*)0x2000000001dc = 0); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x2000000001e0, 5, 0, 3)); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x2000000001e0, 0, 3, 1)); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x2000000001e0, 8, 4, 4)); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x2000000001e1, 0, 0, 4)); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x2000000001e1, 0, 4, 4)); NONFAILING(*(uint16_t*)0x2000000001e2 = 0xfffe); NONFAILING(*(uint32_t*)0x2000000001e4 = 0xd1); NONFAILING(*(uint8_t*)0x2000000001e8 = 0x95); NONFAILING(*(uint8_t*)0x2000000001e9 = 0); NONFAILING(*(uint16_t*)0x2000000001ea = 0); NONFAILING(*(uint32_t*)0x2000000001ec = 0); NONFAILING(*(uint64_t*)0x200000000110 = 0x2000000000c0); NONFAILING(memcpy((void*)0x2000000000c0, "GPL\000", 4)); NONFAILING(*(uint32_t*)0x200000000118 = 5); NONFAILING(*(uint32_t*)0x20000000011c = 0); NONFAILING(*(uint64_t*)0x200000000120 = 0); NONFAILING(*(uint32_t*)0x200000000128 = 0); NONFAILING(*(uint32_t*)0x20000000012c = 8); NONFAILING(memset((void*)0x200000000130, 0, 16)); NONFAILING(*(uint32_t*)0x200000000140 = 0); NONFAILING(*(uint32_t*)0x200000000144 = 0x25); NONFAILING(*(uint32_t*)0x200000000148 = -1); NONFAILING(*(uint32_t*)0x20000000014c = 8); NONFAILING(*(uint64_t*)0x200000000150 = 0); NONFAILING(*(uint32_t*)0x200000000158 = 0); NONFAILING(*(uint32_t*)0x20000000015c = 0x10); NONFAILING(*(uint64_t*)0x200000000160 = 0); NONFAILING(*(uint32_t*)0x200000000168 = 0); NONFAILING(*(uint32_t*)0x20000000016c = 0); NONFAILING(*(uint32_t*)0x200000000170 = 0); NONFAILING(*(uint32_t*)0x200000000174 = 0); NONFAILING(*(uint64_t*)0x200000000178 = 0); NONFAILING(*(uint64_t*)0x200000000180 = 0); NONFAILING(*(uint32_t*)0x200000000188 = 0x10); NONFAILING(*(uint32_t*)0x20000000018c = 4); NONFAILING(*(uint32_t*)0x200000000190 = 0); syscall(__NR_bpf, /*cmd=*/5ul, /*arg=*/0x200000000100ul, /*size=*/0x94ul); // bpf$BPF_RAW_TRACEPOINT_OPEN arguments: [ // cmd: const = 0x11 (8 bytes) // arg: ptr[in, bpf_raw_tracepoint] { // bpf_raw_tracepoint { // name: ptr[in, buffer] { // buffer: {76 69 72 74 69 6f 5f 74 72 61 6e 73 70 6f 72 74 5f 61 6c // 6c 6f 63 5f 70 6b 74 00} (length 0x1b) // } // prog_fd: fd_bpf_prog_raw_tracepoint (resource) // pad: const = 0x0 (4 bytes) // cookie: int64 = 0x0 (8 bytes) // } // } // size: len = 0x18 (8 bytes) // ] // returns fd_perf_base NONFAILING(*(uint64_t*)0x2000000000c0 = 0x200000000040); NONFAILING( memcpy((void*)0x200000000040, "virtio_transport_alloc_pkt\000", 27)); NONFAILING(*(uint32_t*)0x2000000000c8 = r[0]); NONFAILING(*(uint32_t*)0x2000000000cc = 0); NONFAILING(*(uint64_t*)0x2000000000d0 = 0); syscall(__NR_bpf, /*cmd=*/0x11ul, /*arg=*/0x2000000000c0ul, /*size=*/0x18ul); // socket$vsock_stream arguments: [ // domain: const = 0x28 (8 bytes) // type: const = 0x1 (8 bytes) // proto: const = 0x0 (4 bytes) // ] // returns sock_vsock_stream res = syscall(__NR_socket, /*domain=*/0x28ul, /*type=*/1ul, /*proto=*/0); if (res != -1) r[1] = res; // connect$vsock_stream arguments: [ // fd: sock_vsock_stream (resource) // addr: ptr[in, sockaddr_vm] { // sockaddr_vm { // svm_family: const = 0x28 (2 bytes) // svm_reserved1: const = 0x0 (2 bytes) // svm_port: vmaddr_port = 0x0 (4 bytes) // svm_cid: union vmaddr_cid { // local: const = 0x1 (4 bytes) // } // svm_zero: const = 0x0 (4 bytes) // } // } // addrlen: len = 0x10 (8 bytes) // ] NONFAILING(*(uint16_t*)0x200000000100 = 0x28); NONFAILING(*(uint16_t*)0x200000000102 = 0); NONFAILING(*(uint32_t*)0x200000000104 = 0); NONFAILING(*(uint32_t*)0x200000000108 = 1); NONFAILING(*(uint32_t*)0x20000000010c = 0); syscall(__NR_connect, /*fd=*/r[1], /*addr=*/0x200000000100ul, /*addrlen=*/0x10ul); } int main(void) { syscall(__NR_mmap, /*addr=*/0x1ffffffff000ul, /*len=*/0x1000ul, /*prot=*/0ul, /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul, /*fd=*/(intptr_t)-1, /*offset=*/0ul); syscall(__NR_mmap, /*addr=*/0x200000000000ul, /*len=*/0x1000000ul, /*prot=PROT_WRITE|PROT_READ|PROT_EXEC*/ 7ul, /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul, /*fd=*/(intptr_t)-1, /*offset=*/0ul); syscall(__NR_mmap, /*addr=*/0x200001000000ul, /*len=*/0x1000ul, /*prot=*/0ul, /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul, /*fd=*/(intptr_t)-1, /*offset=*/0ul); const char* reason; (void)reason; if ((reason = setup_802154())) printf("the reproducer may not work as expected: 802154 injection setup " "failed: %s\n", reason); install_segv_handler(); do_sandbox_none(); return 0; }