// https://syzkaller.appspot.com/bug?id=fbdd184fa117ff48a7928f7b3d8d30792c8e4ba8 // 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 __attribute__((noreturn)) static void doexit(int status) { volatile unsigned i; syscall(__NR_exit_group, status); for (i = 0;; i++) { } } #include #include const int kFailStatus = 67; const int kRetryStatus = 69; static void fail(const char* msg, ...) { int e = errno; 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; \ } 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 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 #define PATH_PREFIX \ "PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin " #define PATH_PREFIX_LEN (sizeof(PATH_PREFIX) - 1) static void execute_command(const char* format, ...) { va_list args; char command[PATH_PREFIX_LEN + COMMAND_MAX_LEN]; int rv; va_start(args, format); memcpy(command, PATH_PREFIX, PATH_PREFIX_LEN); vsnprintf_check(command + PATH_PREFIX_LEN, COMMAND_MAX_LEN, 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; static int tun_frags_enabled; #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" #define IFF_NAPI 0x0010 #define IFF_NAPI_FRAGS 0x0020 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 | 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) fail("tun: ioctl(TUNSETIFF) failed"); } if (ioctl(tunfd, TUNGETIFF, (void*)&ifr) < 0) fail("tun: ioctl(TUNGETIFF) failed"); tun_frags_enabled = (ifr.ifr_flags & IFF_NAPI_FRAGS) != 0; 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); } #define MAX_FRAGS 4 struct vnet_fragmentation { uint32_t full; uint32_t count; uint32_t frags[MAX_FRAGS]; }; static uintptr_t syz_emit_ethernet(uintptr_t a0, uintptr_t a1, uintptr_t a2) { if (tunfd < 0) return (uintptr_t)-1; uint32_t length = a0; char* data = (char*)a1; struct vnet_fragmentation* frags = (struct vnet_fragmentation*)a2; struct iovec vecs[MAX_FRAGS + 1]; uint32_t nfrags = 0; if (!tun_frags_enabled || frags == NULL) { vecs[nfrags].iov_base = data; vecs[nfrags].iov_len = length; nfrags++; } else { bool full = true; uint32_t i, count = 0; full = frags->full; count = frags->count; if (count > MAX_FRAGS) count = MAX_FRAGS; for (i = 0; i < count && length != 0; i++) { uint32_t size = 0; size = frags->frags[i]; if (size > length) size = length; vecs[nfrags].iov_base = data; vecs[nfrags].iov_len = size; nfrags++; data += size; length -= size; } if (length != 0 && (full || nfrags == 0)) { vecs[nfrags].iov_base = data; vecs[nfrags].iov_len = length; nfrags++; } } return writev(tunfd, vecs, nfrags); } long r[219]; void loop() { memset(r, -1, sizeof(r)); r[0] = syscall(__NR_mmap, 0x20000000ul, 0xfff000ul, 0x3ul, 0x32ul, 0xfffffffffffffffful, 0x0ul); *(uint32_t*)0x20000000 = (uint32_t)0x2; *(uint32_t*)0x20000004 = (uint32_t)0x2; *(uint32_t*)0x20000008 = (uint32_t)0x3; *(uint32_t*)0x2000000c = (uint32_t)0x1; *(uint32_t*)0x20000010 = (uint32_t)0x20040; *(uint32_t*)0x20000014 = (uint32_t)0xffffffffffffffff; *(uint32_t*)0x20000018 = (uint32_t)0x6; *(uint8_t*)0x2000001c = (uint8_t)0x0; *(uint8_t*)0x2000001d = (uint8_t)0x0; *(uint8_t*)0x2000001e = (uint8_t)0x0; *(uint8_t*)0x2000001f = (uint8_t)0x0; *(uint8_t*)0x20000020 = (uint8_t)0x0; *(uint8_t*)0x20000021 = (uint8_t)0x0; *(uint8_t*)0x20000022 = (uint8_t)0x0; *(uint8_t*)0x20000023 = (uint8_t)0x0; *(uint8_t*)0x20000024 = (uint8_t)0x0; *(uint8_t*)0x20000025 = (uint8_t)0x0; *(uint8_t*)0x20000026 = (uint8_t)0x0; *(uint8_t*)0x20000027 = (uint8_t)0x0; *(uint8_t*)0x20000028 = (uint8_t)0x0; *(uint8_t*)0x20000029 = (uint8_t)0x0; *(uint8_t*)0x2000002a = (uint8_t)0x0; *(uint8_t*)0x2000002b = (uint8_t)0x0; *(uint8_t*)0x2000002c = (uint8_t)0x0; *(uint8_t*)0x2000002d = (uint8_t)0x0; *(uint8_t*)0x2000002e = (uint8_t)0x0; *(uint8_t*)0x2000002f = (uint8_t)0x0; *(uint8_t*)0x20000030 = (uint8_t)0x0; *(uint8_t*)0x20000031 = (uint8_t)0x0; *(uint8_t*)0x20000032 = (uint8_t)0x0; *(uint8_t*)0x20000033 = (uint8_t)0x0; *(uint8_t*)0x20000034 = (uint8_t)0x0; *(uint8_t*)0x20000035 = (uint8_t)0x0; *(uint8_t*)0x20000036 = (uint8_t)0x0; *(uint8_t*)0x20000037 = (uint8_t)0x0; *(uint8_t*)0x20000038 = (uint8_t)0x0; *(uint8_t*)0x20000039 = (uint8_t)0x0; *(uint8_t*)0x2000003a = (uint8_t)0x0; *(uint8_t*)0x2000003b = (uint8_t)0x0; *(uint8_t*)0x2000003c = (uint8_t)0x0; *(uint8_t*)0x2000003d = (uint8_t)0x0; *(uint8_t*)0x2000003e = (uint8_t)0x0; *(uint8_t*)0x2000003f = (uint8_t)0x0; *(uint8_t*)0x20000040 = (uint8_t)0x0; *(uint8_t*)0x20000041 = (uint8_t)0x0; *(uint8_t*)0x20000042 = (uint8_t)0x0; *(uint8_t*)0x20000043 = (uint8_t)0x0; *(uint8_t*)0x20000044 = (uint8_t)0x0; *(uint8_t*)0x20000045 = (uint8_t)0x0; *(uint8_t*)0x20000046 = (uint8_t)0x0; *(uint8_t*)0x20000047 = (uint8_t)0x0; *(uint8_t*)0x20000048 = (uint8_t)0x0; *(uint8_t*)0x20000049 = (uint8_t)0x0; *(uint8_t*)0x2000004a = (uint8_t)0x0; *(uint8_t*)0x2000004b = (uint8_t)0x0; *(uint8_t*)0x2000004c = (uint8_t)0x0; *(uint8_t*)0x2000004d = (uint8_t)0x0; *(uint8_t*)0x2000004e = (uint8_t)0x0; *(uint8_t*)0x2000004f = (uint8_t)0x0; *(uint8_t*)0x20000050 = (uint8_t)0x0; *(uint8_t*)0x20000051 = (uint8_t)0x0; *(uint8_t*)0x20000052 = (uint8_t)0x0; *(uint8_t*)0x20000053 = (uint8_t)0x0; *(uint8_t*)0x20000054 = (uint8_t)0x0; *(uint8_t*)0x20000055 = (uint8_t)0x0; *(uint8_t*)0x20000056 = (uint8_t)0x0; *(uint8_t*)0x20000057 = (uint8_t)0x0; *(uint8_t*)0x20000058 = (uint8_t)0x0; *(uint8_t*)0x20000059 = (uint8_t)0x0; *(uint8_t*)0x2000005a = (uint8_t)0x0; *(uint8_t*)0x2000005b = (uint8_t)0x0; r[72] = syscall(__NR_ioctl, 0xfffffffffffffffful, 0xc0605345ul, 0x20000000ul); memcpy((void*)0x20858eaa, "\xe0\x36\x97\x10\xc5\x5e", 6); memcpy((void*)0x20858eb0, "\x51\xf9\x58\x2a\x2d\x52", 6); *(uint16_t*)0x20858eb6 = (uint16_t)0x91; STORE_BY_BITMASK(uint16_t, 0x20858eb8, 0xa0a, 0, 3); STORE_BY_BITMASK(uint16_t, 0x20858eb8, 0x80000000, 3, 1); STORE_BY_BITMASK(uint16_t, 0x20858eb8, 0x2, 4, 12); *(uint16_t*)0x20858eba = (uint16_t)0x81; STORE_BY_BITMASK(uint16_t, 0x20858ebc, 0x9, 0, 3); STORE_BY_BITMASK(uint16_t, 0x20858ebc, 0x2, 3, 1); STORE_BY_BITMASK(uint16_t, 0x20858ebc, 0xde4, 4, 12); *(uint16_t*)0x20858ebe = (uint16_t)0xffef; STORE_BY_BITMASK(uint8_t, 0x20858ec0, 0x19, 0, 4); STORE_BY_BITMASK(uint8_t, 0x20858ec0, 0x4, 4, 4); STORE_BY_BITMASK(uint8_t, 0x20858ec1, 0x1, 0, 2); STORE_BY_BITMASK(uint8_t, 0x20858ec1, 0x6, 2, 6); *(uint16_t*)0x20858ec2 = (uint16_t)0xd800; *(uint16_t*)0x20858ec4 = (uint16_t)0x6600; *(uint16_t*)0x20858ec6 = (uint16_t)0xe400; *(uint8_t*)0x20858ec8 = (uint8_t)0x6e; *(uint8_t*)0x20858ec9 = (uint8_t)0x33; *(uint16_t*)0x20858eca = (uint16_t)0x0; *(uint8_t*)0x20858ecc = (uint8_t)0xac; *(uint8_t*)0x20858ecd = (uint8_t)0x14; *(uint8_t*)0x20858ece = (uint8_t)0x0; *(uint8_t*)0x20858ecf = (uint8_t)0xbb; *(uint32_t*)0x20858ed0 = (uint32_t)0x10000e0; *(uint8_t*)0x20858ed4 = (uint8_t)0x94; *(uint8_t*)0x20858ed5 = (uint8_t)0x6; *(uint32_t*)0x20858ed6 = (uint32_t)0x1000000; *(uint8_t*)0x20858eda = (uint8_t)0x0; *(uint8_t*)0x20858edb = (uint8_t)0x86; *(uint8_t*)0x20858edc = (uint8_t)0x10; *(uint32_t*)0x20858edd = (uint32_t)0xff0f0000; *(uint8_t*)0x20858ee1 = (uint8_t)0x7; *(uint8_t*)0x20858ee2 = (uint8_t)0x2; *(uint8_t*)0x20858ee3 = (uint8_t)0x3; *(uint8_t*)0x20858ee4 = (uint8_t)0x2; *(uint8_t*)0x20858ee5 = (uint8_t)0x0; *(uint8_t*)0x20858ee6 = (uint8_t)0x2; *(uint8_t*)0x20858ee7 = (uint8_t)0x7; *(uint8_t*)0x20858ee8 = (uint8_t)0x2; *(uint8_t*)0x20858ee9 = (uint8_t)0x0; *(uint8_t*)0x20858eea = (uint8_t)0x2; *(uint8_t*)0x20858eeb = (uint8_t)0x83; *(uint8_t*)0x20858eec = (uint8_t)0xf; *(uint8_t*)0x20858eed = (uint8_t)0x1; *(uint32_t*)0x20858eee = (uint32_t)0x0; *(uint32_t*)0x20858ef2 = (uint32_t)0xffffffff; *(uint32_t*)0x20858ef6 = (uint32_t)0xffffffff; *(uint8_t*)0x20858efa = (uint8_t)0x44; *(uint8_t*)0x20858efb = (uint8_t)0x28; *(uint8_t*)0x20858efc = (uint8_t)0x2; STORE_BY_BITMASK(uint8_t, 0x20858efd, 0x1, 0, 4); STORE_BY_BITMASK(uint8_t, 0x20858efd, 0x1, 4, 4); *(uint32_t*)0x20858efe = (uint32_t)0x100007f; *(uint32_t*)0x20858f02 = (uint32_t)0x5000000; *(uint8_t*)0x20858f06 = (uint8_t)0xac; *(uint8_t*)0x20858f07 = (uint8_t)0x14; *(uint8_t*)0x20858f08 = (uint8_t)0x0; *(uint8_t*)0x20858f09 = (uint8_t)0xaa; *(uint32_t*)0x20858f0a = (uint32_t)0x8000000; *(uint32_t*)0x20858f0e = (uint32_t)0xff030000; *(uint32_t*)0x20858f12 = (uint32_t)0x20000e0; *(uint32_t*)0x20858f16 = (uint32_t)0xff7f0000; *(uint8_t*)0x20858f1a = (uint8_t)0xac; *(uint8_t*)0x20858f1b = (uint8_t)0x14; *(uint8_t*)0x20858f1c = (uint8_t)0x0; *(uint8_t*)0x20858f1d = (uint8_t)0xaa; *(uint32_t*)0x20858f1e = (uint32_t)0x1000000; *(uint8_t*)0x20858f22 = (uint8_t)0x0; *(uint8_t*)0x20858f24 = (uint8_t)0xc; *(uint8_t*)0x20858f25 = (uint8_t)0x0; *(uint16_t*)0x20858f26 = (uint16_t)0x0; *(uint8_t*)0x20858f28 = (uint8_t)0xffffffff00000000; *(uint8_t*)0x20858f29 = (uint8_t)0x3; *(uint16_t*)0x20858f2a = (uint16_t)0x0; STORE_BY_BITMASK(uint8_t, 0x20858f2c, 0x1b, 0, 4); STORE_BY_BITMASK(uint8_t, 0x20858f2c, 0x4, 4, 4); STORE_BY_BITMASK(uint8_t, 0x20858f2d, 0x3f, 0, 2); STORE_BY_BITMASK(uint8_t, 0x20858f2d, 0x9, 2, 6); *(uint16_t*)0x20858f2e = (uint16_t)0x400; *(uint16_t*)0x20858f30 = (uint16_t)0x6400; *(uint16_t*)0x20858f32 = (uint16_t)0x8000; *(uint8_t*)0x20858f34 = (uint8_t)0x1; *(uint8_t*)0x20858f35 = (uint8_t)0x5d; *(uint16_t*)0x20858f36 = (uint16_t)0x8000; *(uint32_t*)0x20858f38 = (uint32_t)0x20000e0; *(uint32_t*)0x20858f3c = (uint32_t)0xffffffff; *(uint8_t*)0x20858f40 = (uint8_t)0x7; *(uint8_t*)0x20858f41 = (uint8_t)0x13; *(uint8_t*)0x20858f42 = (uint8_t)0x6; *(uint32_t*)0x20858f43 = (uint32_t)0x20000e0; *(uint8_t*)0x20858f47 = (uint8_t)0xac; *(uint8_t*)0x20858f48 = (uint8_t)0x14; *(uint8_t*)0x20858f49 = (uint8_t)0x0; *(uint8_t*)0x20858f4a = (uint8_t)0xaa; *(uint32_t*)0x20858f4b = (uint32_t)0xffffffff; *(uint8_t*)0x20858f4f = (uint8_t)0xac; *(uint8_t*)0x20858f50 = (uint8_t)0x14; *(uint8_t*)0x20858f51 = (uint8_t)0x0; *(uint8_t*)0x20858f52 = (uint8_t)0xbb; *(uint8_t*)0x20858f53 = (uint8_t)0x86; *(uint8_t*)0x20858f54 = (uint8_t)0x12; *(uint32_t*)0x20858f55 = (uint32_t)0x80000000; *(uint8_t*)0x20858f59 = (uint8_t)0x5; *(uint8_t*)0x20858f5a = (uint8_t)0x2; *(uint8_t*)0x20858f5b = (uint8_t)0x5; *(uint8_t*)0x20858f5c = (uint8_t)0x2; *(uint8_t*)0x20858f5d = (uint8_t)0x5; *(uint8_t*)0x20858f5e = (uint8_t)0x2; *(uint8_t*)0x20858f5f = (uint8_t)0x6; *(uint8_t*)0x20858f60 = (uint8_t)0x2; *(uint8_t*)0x20858f61 = (uint8_t)0x7; *(uint8_t*)0x20858f62 = (uint8_t)0x2; *(uint8_t*)0x20858f63 = (uint8_t)0x2; *(uint8_t*)0x20858f64 = (uint8_t)0x2; *(uint8_t*)0x20858f65 = (uint8_t)0x94; *(uint8_t*)0x20858f66 = (uint8_t)0x6; *(uint32_t*)0x20858f67 = (uint32_t)0x5000000; *(uint8_t*)0x20858f6b = (uint8_t)0x0; *(uint8_t*)0x20858f6c = (uint8_t)0x94; *(uint8_t*)0x20858f6d = (uint8_t)0x6; *(uint32_t*)0x20858f6e = (uint32_t)0x3000000; *(uint8_t*)0x20858f72 = (uint8_t)0x83; *(uint8_t*)0x20858f73 = (uint8_t)0x7; *(uint8_t*)0x20858f74 = (uint8_t)0xe9; *(uint32_t*)0x20858f75 = (uint32_t)0x0; *(uint8_t*)0x20858f79 = (uint8_t)0x86; *(uint8_t*)0x20858f7a = (uint8_t)0x8; *(uint32_t*)0x20858f7b = (uint32_t)0x1000000; *(uint8_t*)0x20858f7f = (uint8_t)0x5; *(uint8_t*)0x20858f80 = (uint8_t)0x2; *(uint8_t*)0x20858f81 = (uint8_t)0x7; *(uint8_t*)0x20858f82 = (uint8_t)0x7; *(uint8_t*)0x20858f83 = (uint8_t)0x100; *(uint32_t*)0x20858f84 = (uint32_t)0xffffffff; *(uint8_t*)0x20858f88 = (uint8_t)0x83; *(uint8_t*)0x20858f89 = (uint8_t)0x2; *(uint8_t*)0x20858f8a = (uint8_t)0x83; *(uint8_t*)0x20858f8b = (uint8_t)0xb; *(uint8_t*)0x20858f8c = (uint8_t)0x2; *(uint32_t*)0x20858f8d = (uint32_t)0x10000e0; *(uint32_t*)0x20858f91 = (uint32_t)0x20000e0; struct csum_inet csum_216; csum_inet_init(&csum_216); csum_inet_update(&csum_216, (const uint8_t*)0x20858f24, 116); *(uint16_t*)0x20858f26 = csum_inet_digest(&csum_216); struct csum_inet csum_217; csum_inet_init(&csum_217); csum_inet_update(&csum_217, (const uint8_t*)0x20858ec0, 100); *(uint16_t*)0x20858eca = csum_inet_digest(&csum_217); r[218] = syz_emit_ethernet(0xeeul, 0x20858eaaul, 0x20000000ul); } int main() { setup_tun(0, true); loop(); return 0; }