// https://syzkaller.appspot.com/bug?id=466bb327d275b50e6a283ef3cdfc9ae875bd837d // autogenerated by syzkaller (http://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 const int kFailStatus = 67; const int kRetryStatus = 69; __attribute__((noreturn)) static void doexit(int status) { volatile unsigned i; syscall(__NR_exit_group, status); for (i = 0;; i++) { } } __attribute__((noreturn)) static void fail(const char* msg, ...) { int e = errno; fflush(stdout); va_list args; va_start(args, msg); vfprintf(stderr, msg, args); va_end(args); fprintf(stderr, " (errno %d)\n", e); doexit((e == ENOMEM || e == EAGAIN) ? kRetryStatus : kFailStatus); } #define BITMASK_LEN(type, bf_len) (type)((1ull << (bf_len)) - 1) #define BITMASK_LEN_OFF(type, bf_off, bf_len) \ (type)(BITMASK_LEN(type, (bf_len)) << (bf_off)) #define STORE_BY_BITMASK(type, addr, val, bf_off, bf_len) \ if ((bf_off) == 0 && (bf_len) == 0) { \ *(type*)(addr) = (type)(val); \ } else { \ type new_val = *(type*)(addr); \ new_val &= ~BITMASK_LEN_OFF(type, (bf_off), (bf_len)); \ new_val |= ((type)(val)&BITMASK_LEN(type, (bf_len))) << (bf_off); \ *(type*)(addr) = new_val; \ } static void use_temporary_dir() { char tmpdir_template[] = "./syzkaller.XXXXXX"; char* tmpdir = mkdtemp(tmpdir_template); if (!tmpdir) fail("failed to mkdtemp"); if (chmod(tmpdir, 0777)) fail("failed to chmod"); if (chdir(tmpdir)) fail("failed to chdir"); } static void vsnprintf_check(char* str, size_t size, const char* format, va_list args) { int rv; rv = vsnprintf(str, size, format, args); if (rv < 0) fail("tun: snprintf failed"); if ((size_t)rv >= size) fail("tun: string '%s...' doesn't fit into buffer", str); } static void snprintf_check(char* str, size_t size, const char* format, ...) { va_list args; va_start(args, format); vsnprintf_check(str, size, format, args); va_end(args); } #define COMMAND_MAX_LEN 128 static void execute_command(const char* format, ...) { va_list args; char command[COMMAND_MAX_LEN]; int rv; va_start(args, format); vsnprintf_check(command, sizeof(command), format, args); rv = system(command); if (rv != 0) fail("tun: command \"%s\" failed with code %d", &command[0], rv); va_end(args); } static int tunfd = -1; #define SYZ_TUN_MAX_PACKET_SIZE 1000 #define MAX_PIDS 32 #define ADDR_MAX_LEN 32 #define LOCAL_MAC "aa:aa:aa:aa:aa:%02hx" #define REMOTE_MAC "bb:bb:bb:bb:bb:%02hx" #define LOCAL_IPV4 "172.20.%d.170" #define REMOTE_IPV4 "172.20.%d.187" #define LOCAL_IPV6 "fe80::%02hxaa" #define REMOTE_IPV6 "fe80::%02hxbb" static void initialize_tun(uint64_t pid) { if (pid >= MAX_PIDS) fail("tun: no more than %d executors", MAX_PIDS); int id = pid; tunfd = open("/dev/net/tun", O_RDWR | O_NONBLOCK); if (tunfd == -1) fail("tun: can't open /dev/net/tun"); char iface[IFNAMSIZ]; snprintf_check(iface, sizeof(iface), "syz%d", id); struct ifreq ifr; memset(&ifr, 0, sizeof(ifr)); strncpy(ifr.ifr_name, iface, IFNAMSIZ); ifr.ifr_flags = IFF_TAP | IFF_NO_PI; if (ioctl(tunfd, TUNSETIFF, (void*)&ifr) < 0) fail("tun: ioctl(TUNSETIFF) failed"); char local_mac[ADDR_MAX_LEN]; snprintf_check(local_mac, sizeof(local_mac), LOCAL_MAC, id); char remote_mac[ADDR_MAX_LEN]; snprintf_check(remote_mac, sizeof(remote_mac), REMOTE_MAC, id); char local_ipv4[ADDR_MAX_LEN]; snprintf_check(local_ipv4, sizeof(local_ipv4), LOCAL_IPV4, id); char remote_ipv4[ADDR_MAX_LEN]; snprintf_check(remote_ipv4, sizeof(remote_ipv4), REMOTE_IPV4, id); char local_ipv6[ADDR_MAX_LEN]; snprintf_check(local_ipv6, sizeof(local_ipv6), LOCAL_IPV6, id); char remote_ipv6[ADDR_MAX_LEN]; snprintf_check(remote_ipv6, sizeof(remote_ipv6), REMOTE_IPV6, id); execute_command("sysctl -w net.ipv6.conf.%s.accept_dad=0", iface); execute_command("sysctl -w net.ipv6.conf.%s.router_solicitations=0", iface); execute_command("ip link set dev %s address %s", iface, local_mac); execute_command("ip addr add %s/24 dev %s", local_ipv4, iface); execute_command("ip -6 addr add %s/120 dev %s", local_ipv6, iface); execute_command("ip neigh add %s lladdr %s dev %s nud permanent", remote_ipv4, remote_mac, iface); execute_command("ip -6 neigh add %s lladdr %s dev %s nud permanent", remote_ipv6, remote_mac, iface); execute_command("ip link set dev %s up", iface); } static void setup_tun(uint64_t pid, bool enable_tun) { if (enable_tun) initialize_tun(pid); } struct csum_inet { uint32_t acc; }; static void csum_inet_init(struct csum_inet* csum) { csum->acc = 0; } static void csum_inet_update(struct csum_inet* csum, const uint8_t* data, size_t length) { if (length == 0) return; size_t i; for (i = 0; i < length - 1; i += 2) csum->acc += *(uint16_t*)&data[i]; if (length & 1) csum->acc += (uint16_t)data[length - 1]; while (csum->acc > 0xffff) csum->acc = (csum->acc & 0xffff) + (csum->acc >> 16); } static uint16_t csum_inet_digest(struct csum_inet* csum) { return ~csum->acc; } static uintptr_t syz_emit_ethernet(uintptr_t a0, uintptr_t a1) { if (tunfd < 0) return (uintptr_t)-1; int64_t length = a0; char* data = (char*)a1; return write(tunfd, data, length); } 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 = 128 << 20; setrlimit(RLIMIT_AS, &rlim); rlim.rlim_cur = rlim.rlim_max = 8 << 20; setrlimit(RLIMIT_MEMLOCK, &rlim); rlim.rlim_cur = rlim.rlim_max = 1 << 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); unshare(CLONE_NEWNS); unshare(CLONE_NEWIPC); unshare(CLONE_IO); } 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) { close(fd); return false; } close(fd); return true; } static int real_uid; static int real_gid; static int epid; static bool etun; __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)) fail("write of /proc/self/uid_map failed"); if (!write_file("/proc/self/gid_map", "0 %d 1\n", real_gid)) fail("write of /proc/self/gid_map failed"); setup_tun(epid, etun); if (mkdir("./syz-tmp", 0777)) fail("mkdir(syz-tmp) failed"); if (mount("", "./syz-tmp", "tmpfs", 0, NULL)) fail("mount(tmpfs) failed"); if (mkdir("./syz-tmp/newroot", 0777)) fail("mkdir failed"); if (mkdir("./syz-tmp/newroot/dev", 0700)) fail("mkdir failed"); if (mount("/dev", "./syz-tmp/newroot/dev", NULL, MS_BIND | MS_REC | MS_PRIVATE, NULL)) fail("mount(dev) failed"); if (mkdir("./syz-tmp/newroot/proc", 0700)) fail("mkdir failed"); if (mount(NULL, "./syz-tmp/newroot/proc", "proc", 0, NULL)) fail("mount(proc) failed"); if (mkdir("./syz-tmp/pivot", 0777)) fail("mkdir failed"); if (syscall(SYS_pivot_root, "./syz-tmp", "./syz-tmp/pivot")) { if (chdir("./syz-tmp")) fail("chdir failed"); } else { if (chdir("/")) fail("chdir failed"); if (umount2("./pivot", MNT_DETACH)) fail("umount failed"); } if (chroot("./newroot")) fail("chroot failed"); if (chdir("/")) fail("chdir failed"); 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)) fail("capget failed"); 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)) fail("capset failed"); loop(); doexit(1); } static int do_sandbox_namespace(int executor_pid, bool enable_tun) { real_uid = getuid(); real_gid = getgid(); epid = executor_pid; etun = enable_tun; mprotect(sandbox_stack, 4096, PROT_NONE); return clone( namespace_sandbox_proc, &sandbox_stack[sizeof(sandbox_stack) - 64], CLONE_NEWUSER | CLONE_NEWPID | CLONE_NEWUTS | CLONE_NEWNET, NULL); } long r[132]; void loop() { memset(r, -1, sizeof(r)); r[0] = syscall(__NR_mmap, 0x20000000ul, 0xfff000ul, 0x3ul, 0x32ul, 0xfffffffffffffffful, 0x0ul); *(uint8_t*)0x200d8000 = (uint8_t)0xbb; *(uint8_t*)0x200d8001 = (uint8_t)0xbb; *(uint8_t*)0x200d8002 = (uint8_t)0xbb; *(uint8_t*)0x200d8003 = (uint8_t)0xbb; *(uint8_t*)0x200d8004 = (uint8_t)0xbb; *(uint8_t*)0x200d8005 = (uint8_t)0x0; *(uint8_t*)0x200d8006 = (uint8_t)0xaa; *(uint8_t*)0x200d8007 = (uint8_t)0xaa; *(uint8_t*)0x200d8008 = (uint8_t)0xaa; *(uint8_t*)0x200d8009 = (uint8_t)0xaa; *(uint8_t*)0x200d800a = (uint8_t)0xaa; *(uint8_t*)0x200d800b = (uint8_t)0x0; *(uint16_t*)0x200d800c = (uint16_t)0xdd86; STORE_BY_BITMASK(uint8_t, 0x200d800e, 0x0, 0, 4); STORE_BY_BITMASK(uint8_t, 0x200d800e, 0x6, 4, 4); memcpy((void*)0x200d800f, "\xa2\x28\xaf", 3); *(uint16_t*)0x200d8012 = (uint16_t)0x2200; *(uint8_t*)0x200d8014 = (uint8_t)0x0; *(uint8_t*)0x200d8015 = (uint8_t)0x0; *(uint8_t*)0x200d8016 = (uint8_t)0xfe; *(uint8_t*)0x200d8017 = (uint8_t)0x80; *(uint8_t*)0x200d8018 = (uint8_t)0x0; *(uint8_t*)0x200d8019 = (uint8_t)0x0; *(uint8_t*)0x200d801a = (uint8_t)0x0; *(uint8_t*)0x200d801b = (uint8_t)0x0; *(uint8_t*)0x200d801c = (uint8_t)0x0; *(uint8_t*)0x200d801d = (uint8_t)0x0; *(uint8_t*)0x200d801e = (uint8_t)0x0; *(uint8_t*)0x200d801f = (uint8_t)0x0; *(uint8_t*)0x200d8020 = (uint8_t)0x0; *(uint8_t*)0x200d8021 = (uint8_t)0x0; *(uint8_t*)0x200d8022 = (uint8_t)0x0; *(uint8_t*)0x200d8023 = (uint8_t)0x0; *(uint8_t*)0x200d8024 = (uint8_t)0x0; *(uint8_t*)0x200d8025 = (uint8_t)0xaa; *(uint8_t*)0x200d8026 = (uint8_t)0xfe; *(uint8_t*)0x200d8027 = (uint8_t)0x80; *(uint8_t*)0x200d8028 = (uint8_t)0x0; *(uint8_t*)0x200d8029 = (uint8_t)0x0; *(uint8_t*)0x200d802a = (uint8_t)0x0; *(uint8_t*)0x200d802b = (uint8_t)0x0; *(uint8_t*)0x200d802c = (uint8_t)0x0; *(uint8_t*)0x200d802d = (uint8_t)0x0; *(uint8_t*)0x200d802e = (uint8_t)0x0; *(uint8_t*)0x200d802f = (uint8_t)0x0; *(uint8_t*)0x200d8030 = (uint8_t)0x0; *(uint8_t*)0x200d8031 = (uint8_t)0x0; *(uint8_t*)0x200d8032 = (uint8_t)0x0; *(uint8_t*)0x200d8033 = (uint8_t)0x0; *(uint8_t*)0x200d8034 = (uint8_t)0x0; *(uint8_t*)0x200d8035 = (uint8_t)0xaa; *(uint8_t*)0x200d8036 = (uint8_t)0x2f; *(uint8_t*)0x200d8037 = (uint8_t)0x1; *(uint8_t*)0x200d8038 = (uint8_t)0x0; *(uint8_t*)0x200d8039 = (uint8_t)0x0; *(uint8_t*)0x200d803a = (uint8_t)0x0; *(uint8_t*)0x200d803b = (uint8_t)0x0; *(uint8_t*)0x200d803c = (uint8_t)0x0; *(uint8_t*)0x200d803d = (uint8_t)0x0; *(uint8_t*)0x200d803e = (uint8_t)0x5; *(uint8_t*)0x200d803f = (uint8_t)0x0; *(uint8_t*)0x200d8040 = (uint8_t)0xff; *(uint8_t*)0x200d8041 = (uint8_t)0x0; *(uint8_t*)0x200d8042 = (uint8_t)0x7; *(uint8_t*)0x200d8043 = (uint8_t)0x0; *(uint8_t*)0x200d8044 = (uint8_t)0xff; *(uint8_t*)0x200d8045 = (uint8_t)0x0; *(uint8_t*)0x200d8046 = (uint8_t)0x1; *(uint8_t*)0x200d8047 = (uint8_t)0x0; *(uint8_t*)0x200d8048 = (uint8_t)0x4; *(uint8_t*)0x200d8049 = (uint8_t)0x0; *(uint8_t*)0x200d804a = (uint8_t)0x0; *(uint8_t*)0x200d804b = (uint8_t)0x0; *(uint8_t*)0x200d804c = (uint8_t)0x0; *(uint8_t*)0x200d804d = (uint8_t)0x0; *(uint8_t*)0x200d804e = (uint8_t)0x0; *(uint8_t*)0x200d804f = (uint8_t)0x0; *(uint16_t*)0x200d8050 = (uint16_t)0x204e; *(uint16_t*)0x200d8052 = (uint16_t)0x204e; *(uint16_t*)0x200d8054 = (uint16_t)0x800; *(uint16_t*)0x200d8056 = (uint16_t)0x0; struct csum_inet csum_82; csum_inet_init(&csum_82); csum_inet_update(&csum_82, (const uint8_t*)0x200d8016, 16); csum_inet_update(&csum_82, (const uint8_t*)0x200d8026, 16); uint32_t csum_82_chunk_2 = 0x8000000; csum_inet_update(&csum_82, (const uint8_t*)&csum_82_chunk_2, 4); uint32_t csum_82_chunk_3 = 0x11000000; csum_inet_update(&csum_82, (const uint8_t*)&csum_82_chunk_3, 4); csum_inet_update(&csum_82, (const uint8_t*)0x200d8050, 8); *(uint16_t*)0x200d8056 = csum_inet_digest(&csum_82); r[83] = syz_emit_ethernet(0x58ul, 0x200d8000ul); r[84] = syscall(__NR_socket, 0x11ul, 0x10000000803ul, 0x0ul); memcpy((void*)0x2008e000, "\x20\x6f\x01\x00", 4); r[86] = syscall(__NR_setsockopt, r[84], 0x107ul, 0xful, 0x2008e000ul, 0x4ul); *(uint64_t*)0x20cf4f90 = (uint64_t)0x202b0000; *(uint32_t*)0x20cf4f98 = (uint32_t)0x60; *(uint64_t*)0x20cf4fa0 = (uint64_t)0x20da0fc0; *(uint64_t*)0x20cf4fa8 = (uint64_t)0x3; *(uint64_t*)0x20cf4fb0 = (uint64_t)0x208adf10; *(uint64_t*)0x20cf4fb8 = (uint64_t)0x10; *(uint32_t*)0x20cf4fc0 = (uint32_t)0x20000000; *(uint64_t*)0x20cf4fc8 = (uint64_t)0x20d06000; *(uint32_t*)0x20cf4fd0 = (uint32_t)0x60; *(uint64_t*)0x20cf4fd8 = (uint64_t)0x20b8bfb0; *(uint64_t*)0x20cf4fe0 = (uint64_t)0x0; *(uint64_t*)0x20cf4fe8 = (uint64_t)0x20d06fd8; *(uint64_t*)0x20cf4ff0 = (uint64_t)0x10; *(uint32_t*)0x20cf4ff8 = (uint32_t)0x10; *(uint16_t*)0x202b0000 = (uint16_t)0x27; *(uint32_t*)0x202b0004 = (uint32_t)0x4; *(uint32_t*)0x202b0008 = (uint32_t)0x0; *(uint32_t*)0x202b000c = (uint32_t)0x0; *(uint8_t*)0x202b0010 = (uint8_t)0x0; *(uint8_t*)0x202b0011 = (uint8_t)0x0; memcpy((void*)0x202b0012, "\xa2\x84\x02\x7e\x94\x77\x5b\xb0\xa6\x1c\x0a\x37\xf9\x8a\x86" "\xd1\x53\x9b\xce\xf0\x5a\x11\x31\x1b\x56\xeb\x8e\x51\x3a\xfa" "\x21\x84\x79\xb8\xc5\x41\x21\x27\x6c\x0a\x00\x67\x15\xb1\xdd" "\x24\xab\x77\xa3\x9e\xd8\xc2\xa4\xda\x5a\xb8\x2a\xfb\x82\x03" "\x30\xe4\xfe", 63); *(uint64_t*)0x202b0058 = (uint64_t)0x0; *(uint64_t*)0x20da0fc0 = (uint64_t)0x20d06fe3; *(uint64_t*)0x20da0fc8 = (uint64_t)0x1d; *(uint64_t*)0x20da0fd0 = (uint64_t)0x204bd000; *(uint64_t*)0x20da0fd8 = (uint64_t)0x0; *(uint64_t*)0x20da0fe0 = (uint64_t)0x20d06f69; *(uint64_t*)0x20da0fe8 = (uint64_t)0x97; memcpy((void*)0x20d06fe3, "\xcb\x2f\x11\x60\x01\xf8\x13\xbc\xfb\xe7" "\xa8\xd2\x8f\x40\xde\xe9\xcf\xb5\x47\x3c" "\x58\x35\x64\xd2\x5a\xc8\x57\x61\xa0", 29); memcpy((void*)0x20d06f69, "\x0a\x25\x17\x51\xc4\xa4\x0c\x9c\x56\x95\xc2\xec\x3b\x59\x41" "\x82\xc1\x54\x9c\x40\x89\xe1\xa6\x65\xe9\xe0\x17\x46\x37\x32" "\x4d\xdb\xd7\x7a\xb6\x23\x3d\x8f\x8b\x8d\x8d\xcc\xe8\x46\xdc" "\xb7\xf3\xa9\xf5\x61\xc2\x9d\x06\xe5\xc3\x8f\xa4\x06\x9f\xd4" "\xd6\x71\xc4\x1c\x71\x77\x47\x20\x4f\x3c\xde\xeb\xf9\x6d\x81" "\x8d\x63\x77\x5f\xec\x91\x45\xd7\xa9\xff\xc3\x99\x71\xfd\x69" "\x87\x61\xdc\x6d\x55\x78\x6c\xd8\x33\x5f\x2b\xe4\x98\x69\x94" "\x56\x68\x74\x1e\xa2\x8c\xd8\x97\x70\x3d\x09\x74\xd8\xf9\xe8" "\x6e\xd3\x5d\x09\xc6\x7a\xa4\x44\x30\x5d\xf2\xdf\xa4\x41\x15" "\xab\x43\x8c\xc7\x8b\xfc\x7a\x13\xe0\x32\x17\x47\x96\xa2\xbd" "\xf9", 151); *(uint64_t*)0x208adf10 = (uint64_t)0x10; *(uint32_t*)0x208adf18 = (uint32_t)0x88; *(uint32_t*)0x208adf1c = (uint32_t)0x8; *(uint16_t*)0x20d06000 = (uint16_t)0x27; *(uint32_t*)0x20d06004 = (uint32_t)0xec3; *(uint32_t*)0x20d06008 = (uint32_t)0x4; *(uint32_t*)0x20d0600c = (uint32_t)0x5; *(uint8_t*)0x20d06010 = (uint8_t)0x9; *(uint8_t*)0x20d06011 = (uint8_t)0x9e5; memcpy((void*)0x20d06012, "\xde\xc4\x26\x86\x83\x59\x0a\x3f\xbd\xd1\x9e\x53\x47\xa5\xf6" "\xf9\x2d\x04\x5a\x6c\xf9\x0b\x5d\x4f\x75\x58\x79\x0b\xf3\x3e" "\x31\x0d\x6d\x1c\x86\x6e\xdf\xc3\x62\x31\x65\xe0\x18\x41\x63" "\x39\x6d\x47\x6e\xc8\xe2\x9d\x07\x4e\x0e\xc7\xa0\xf3\xde\x8e" "\x40\xbe\xa3", 63); *(uint64_t*)0x20d06058 = (uint64_t)0xa6; *(uint64_t*)0x20d06fd8 = (uint64_t)0x10; *(uint32_t*)0x20d06fe0 = (uint32_t)0x0; *(uint32_t*)0x20d06fe4 = (uint32_t)0x401; r[131] = syscall(__NR_sendmmsg, r[84], 0x20cf4f90ul, 0x2ul, 0x5ul); } int main() { use_temporary_dir(); int pid = do_sandbox_namespace(0, true); int status = 0; while (waitpid(pid, &status, __WALL) != pid) { } return 0; }