| // general protection fault in dst_dev_put (2) |
| // https://syzkaller.appspot.com/bug?id=2d6a9427fceb9941d6d87128130babe7e40baba0 |
| // status:fixed |
| // autogenerated by syzkaller (https://github.com/google/syzkaller) |
| |
| #define _GNU_SOURCE |
| |
| #include <arpa/inet.h> |
| #include <endian.h> |
| #include <errno.h> |
| #include <fcntl.h> |
| #include <net/if.h> |
| #include <net/if_arp.h> |
| #include <netinet/in.h> |
| #include <sched.h> |
| #include <stdarg.h> |
| #include <stdbool.h> |
| #include <stdint.h> |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <string.h> |
| #include <sys/ioctl.h> |
| #include <sys/mman.h> |
| #include <sys/mount.h> |
| #include <sys/prctl.h> |
| #include <sys/resource.h> |
| #include <sys/socket.h> |
| #include <sys/stat.h> |
| #include <sys/syscall.h> |
| #include <sys/time.h> |
| #include <sys/types.h> |
| #include <sys/uio.h> |
| #include <sys/wait.h> |
| #include <unistd.h> |
| |
| #include <linux/capability.h> |
| #include <linux/genetlink.h> |
| #include <linux/if_addr.h> |
| #include <linux/if_ether.h> |
| #include <linux/if_link.h> |
| #include <linux/if_tun.h> |
| #include <linux/in6.h> |
| #include <linux/ip.h> |
| #include <linux/neighbour.h> |
| #include <linux/net.h> |
| #include <linux/netlink.h> |
| #include <linux/rtnetlink.h> |
| #include <linux/tcp.h> |
| #include <linux/veth.h> |
| |
| unsigned long long procid; |
| |
| 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::%02hx" |
| #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::%02hx:%02hx", 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 long syz_genetlink_get_family_id(long name) |
| { |
| char buf[512] = {0}; |
| struct nlmsghdr* hdr = (struct nlmsghdr*)buf; |
| struct genlmsghdr* genlhdr = (struct genlmsghdr*)NLMSG_DATA(hdr); |
| struct nlattr* attr = (struct nlattr*)(genlhdr + 1); |
| hdr->nlmsg_len = |
| sizeof(*hdr) + sizeof(*genlhdr) + sizeof(*attr) + GENL_NAMSIZ; |
| hdr->nlmsg_type = GENL_ID_CTRL; |
| hdr->nlmsg_flags = NLM_F_REQUEST | NLM_F_ACK; |
| genlhdr->cmd = CTRL_CMD_GETFAMILY; |
| attr->nla_type = CTRL_ATTR_FAMILY_NAME; |
| attr->nla_len = sizeof(*attr) + GENL_NAMSIZ; |
| strncpy((char*)(attr + 1), (char*)name, GENL_NAMSIZ); |
| struct iovec iov = {hdr, hdr->nlmsg_len}; |
| struct sockaddr_nl addr = {0}; |
| addr.nl_family = AF_NETLINK; |
| int fd = socket(AF_NETLINK, SOCK_RAW, NETLINK_GENERIC); |
| if (fd == -1) { |
| return -1; |
| } |
| struct msghdr msg = {&addr, sizeof(addr), &iov, 1, NULL, 0, 0}; |
| if (sendmsg(fd, &msg, 0) == -1) { |
| close(fd); |
| return -1; |
| } |
| ssize_t n = recv(fd, buf, sizeof(buf), 0); |
| close(fd); |
| if (n <= 0) { |
| return -1; |
| } |
| if (hdr->nlmsg_type != GENL_ID_CTRL) { |
| return -1; |
| } |
| for (; (char*)attr < buf + n; |
| attr = (struct nlattr*)((char*)attr + NLMSG_ALIGN(attr->nla_len))) { |
| if (attr->nla_type == CTRL_ATTR_FAMILY_ID) |
| return *(uint16_t*)(attr + 1); |
| } |
| return -1; |
| } |
| |
| static void setup_common() |
| { |
| if (mount(0, "/sys/fs/fuse/connections", "fusectl", 0, 0)) { |
| } |
| } |
| |
| static void loop(); |
| |
| static void sandbox_common() |
| { |
| prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0); |
| setpgrp(); |
| setsid(); |
| 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 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); |
| 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); |
| 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); |
| cap_data[0].effective &= ~(1 << CAP_SYS_PTRACE); |
| cap_data[0].permitted &= ~(1 << CAP_SYS_PTRACE); |
| cap_data[0].inheritable &= ~(1 << CAP_SYS_PTRACE); |
| if (syscall(SYS_capset, &cap_hdr, &cap_data)) |
| exit(1); |
| loop(); |
| exit(1); |
| } |
| |
| #define SYZ_HAVE_SANDBOX_NAMESPACE 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); |
| } |
| |
| uint64_t r[3] = {0xffffffffffffffff, 0xffffffffffffffff, 0x0}; |
| |
| void loop(void) |
| { |
| long res = 0; |
| res = syscall(__NR_socket, 0x10, 3, 0x10); |
| if (res != -1) |
| r[0] = res; |
| res = syscall(__NR_socket, 2, 2, 0x88); |
| if (res != -1) |
| r[1] = res; |
| syscall(__NR_ioctl, r[1], 0x1000008912, 0); |
| memcpy((void*)0x20000040, "TIPCv2\000", 7); |
| res = syz_genetlink_get_family_id(0x20000040); |
| if (res != -1) |
| r[2] = res; |
| *(uint64_t*)0x200000c0 = 0; |
| *(uint32_t*)0x200000c8 = 0; |
| *(uint64_t*)0x200000d0 = 0x20000080; |
| *(uint64_t*)0x20000080 = 0x20000340; |
| *(uint32_t*)0x20000340 = 0x88; |
| *(uint16_t*)0x20000344 = r[2]; |
| *(uint16_t*)0x20000346 = 1; |
| *(uint32_t*)0x20000348 = 0; |
| *(uint32_t*)0x2000034c = 0; |
| *(uint8_t*)0x20000350 = 3; |
| *(uint8_t*)0x20000351 = 0; |
| *(uint16_t*)0x20000352 = 0; |
| *(uint16_t*)0x20000354 = 0x10; |
| *(uint16_t*)0x20000356 = 7; |
| *(uint16_t*)0x20000358 = 0xc; |
| *(uint16_t*)0x2000035a = 3; |
| *(uint64_t*)0x2000035c = 0x1f; |
| *(uint16_t*)0x20000364 = 0x1c; |
| *(uint16_t*)0x20000366 = 9; |
| *(uint16_t*)0x20000368 = 8; |
| *(uint16_t*)0x2000036a = 1; |
| *(uint32_t*)0x2000036c = 0x800; |
| *(uint16_t*)0x20000370 = 8; |
| *(uint16_t*)0x20000372 = 1; |
| *(uint32_t*)0x20000374 = 5; |
| *(uint16_t*)0x20000378 = 8; |
| *(uint16_t*)0x2000037a = 2; |
| *(uint32_t*)0x2000037c = 1; |
| *(uint16_t*)0x20000380 = 0x48; |
| *(uint16_t*)0x20000382 = 1; |
| *(uint16_t*)0x20000384 = 0x10; |
| *(uint16_t*)0x20000386 = 1; |
| memcpy((void*)0x20000388, "udp:syz1\000", 9); |
| *(uint16_t*)0x20000394 = 8; |
| *(uint16_t*)0x20000396 = 3; |
| *(uint32_t*)0x20000398 = 0x8001; |
| *(uint16_t*)0x2000039c = 0x2c; |
| *(uint16_t*)0x2000039e = 4; |
| *(uint16_t*)0x200003a0 = 0x14; |
| *(uint16_t*)0x200003a2 = 1; |
| *(uint16_t*)0x200003a4 = 2; |
| *(uint16_t*)0x200003a6 = htobe16(0x4e22); |
| *(uint8_t*)0x200003a8 = 0xac; |
| *(uint8_t*)0x200003a9 = 0x14; |
| *(uint8_t*)0x200003aa = 0x14; |
| *(uint8_t*)0x200003ab = 0xaa; |
| *(uint16_t*)0x200003b4 = 0x14; |
| *(uint16_t*)0x200003b6 = 2; |
| *(uint16_t*)0x200003b8 = 2; |
| *(uint16_t*)0x200003ba = htobe16(0x4e21); |
| *(uint8_t*)0x200003bc = 0xac; |
| *(uint8_t*)0x200003bd = 0x14; |
| *(uint8_t*)0x200003be = 0x14; |
| *(uint8_t*)0x200003bf = 0xbb; |
| *(uint64_t*)0x20000088 = 0x88; |
| *(uint64_t*)0x200000d8 = 1; |
| *(uint64_t*)0x200000e0 = 0; |
| *(uint64_t*)0x200000e8 = 0; |
| *(uint32_t*)0x200000f0 = 0; |
| syscall(__NR_sendmsg, r[0], 0x200000c0, 0x10); |
| } |
| int main(void) |
| { |
| syscall(__NR_mmap, 0x20000000, 0x1000000, 3, 0x32, -1, 0); |
| use_temporary_dir(); |
| do_sandbox_namespace(); |
| return 0; |
| } |