// https://syzkaller.appspot.com/bug?id=7bd6fc42489ba2eb2a9e44977633abd1c2fe0624 // 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 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 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); } long r[146]; void* thr(void* arg) { switch ((long)arg) { case 0: r[0] = syscall(__NR_mmap, 0x20000000ul, 0xfff000ul, 0x3ul, 0x32ul, 0xfffffffffffffffful, 0x0ul); break; case 1: r[1] = syscall(__NR_socket, 0x2ul, 0x1ul, 0x0ul); break; case 2: *(uint16_t*)0x20001000 = (uint16_t)0x2; *(uint16_t*)0x20001002 = (uint16_t)0x204e; *(uint32_t*)0x20001004 = (uint32_t)0x0; *(uint8_t*)0x20001008 = (uint8_t)0x0; *(uint8_t*)0x20001009 = (uint8_t)0x0; *(uint8_t*)0x2000100a = (uint8_t)0x0; *(uint8_t*)0x2000100b = (uint8_t)0x0; *(uint8_t*)0x2000100c = (uint8_t)0x0; *(uint8_t*)0x2000100d = (uint8_t)0x0; *(uint8_t*)0x2000100e = (uint8_t)0x0; *(uint8_t*)0x2000100f = (uint8_t)0x0; r[13] = syscall(__NR_bind, r[1], 0x20001000ul, 0x10ul); break; case 3: r[14] = syscall(__NR_listen, r[1], 0x200000200003fcul); break; case 4: *(uint8_t*)0x20002000 = (uint8_t)0xaa; *(uint8_t*)0x20002001 = (uint8_t)0xaa; *(uint8_t*)0x20002002 = (uint8_t)0xaa; *(uint8_t*)0x20002003 = (uint8_t)0xaa; *(uint8_t*)0x20002004 = (uint8_t)0xaa; *(uint8_t*)0x20002005 = (uint8_t)0x0; memcpy((void*)0x20002006, "\x4c\x61\x12\xcc\x15\xd8", 6); *(uint16_t*)0x2000200c = (uint16_t)0x8; STORE_BY_BITMASK(uint8_t, 0x2000200e, 0x5, 0, 4); STORE_BY_BITMASK(uint8_t, 0x2000200e, 0x4, 4, 4); STORE_BY_BITMASK(uint8_t, 0x2000200f, 0x0, 0, 2); STORE_BY_BITMASK(uint8_t, 0x2000200f, 0x0, 2, 6); *(uint16_t*)0x20002010 = (uint16_t)0x2800; *(uint16_t*)0x20002012 = (uint16_t)0x6400; *(uint16_t*)0x20002014 = (uint16_t)0x0; *(uint8_t*)0x20002016 = (uint8_t)0x0; *(uint8_t*)0x20002017 = (uint8_t)0x6; *(uint16_t*)0x20002018 = (uint16_t)0x0; *(uint8_t*)0x2000201a = (uint8_t)0xac; *(uint8_t*)0x2000201b = (uint8_t)0x14; *(uint8_t*)0x2000201c = (uint8_t)0x0; *(uint8_t*)0x2000201d = (uint8_t)0xbb; *(uint8_t*)0x2000201e = (uint8_t)0xac; *(uint8_t*)0x2000201f = (uint8_t)0x14; *(uint8_t*)0x20002020 = (uint8_t)0x0; *(uint8_t*)0x20002021 = (uint8_t)0xaa; *(uint16_t*)0x20002022 = (uint16_t)0x214e; *(uint16_t*)0x20002024 = (uint16_t)0x204e; *(uint32_t*)0x20002026 = (uint32_t)0x42424242; *(uint32_t*)0x2000202a = (uint32_t)0x42424242; STORE_BY_BITMASK(uint8_t, 0x2000202e, 0x0, 0, 1); STORE_BY_BITMASK(uint8_t, 0x2000202e, 0x0, 1, 3); STORE_BY_BITMASK(uint8_t, 0x2000202e, 0x5, 4, 4); *(uint8_t*)0x2000202f = (uint8_t)0x2; *(uint16_t*)0x20002030 = (uint16_t)0x0; *(uint16_t*)0x20002032 = (uint16_t)0x0; *(uint16_t*)0x20002034 = (uint16_t)0x0; struct csum_inet csum_52; csum_inet_init(&csum_52); csum_inet_update(&csum_52, (const uint8_t*)0x2000201a, 4); csum_inet_update(&csum_52, (const uint8_t*)0x2000201e, 4); uint16_t csum_52_chunk_2 = 0x600; csum_inet_update(&csum_52, (const uint8_t*)&csum_52_chunk_2, 2); uint16_t csum_52_chunk_3 = 0x1400; csum_inet_update(&csum_52, (const uint8_t*)&csum_52_chunk_3, 2); csum_inet_update(&csum_52, (const uint8_t*)0x20002022, 20); *(uint16_t*)0x20002032 = csum_inet_digest(&csum_52); struct csum_inet csum_53; csum_inet_init(&csum_53); csum_inet_update(&csum_53, (const uint8_t*)0x2000200e, 20); *(uint16_t*)0x20002018 = csum_inet_digest(&csum_53); r[54] = syz_emit_ethernet(0x36ul, 0x20002000ul); break; case 5: *(uint8_t*)0x2001a000 = (uint8_t)0x0; *(uint8_t*)0x2001a001 = (uint8_t)0x0; *(uint8_t*)0x2001a002 = (uint8_t)0x0; *(uint8_t*)0x2001a003 = (uint8_t)0x0; *(uint8_t*)0x2001a004 = (uint8_t)0x0; *(uint8_t*)0x2001a005 = (uint8_t)0x0; *(uint8_t*)0x2001a006 = (uint8_t)0x0; *(uint8_t*)0x2001a007 = (uint8_t)0x0; *(uint8_t*)0x2001a008 = (uint8_t)0x0; *(uint8_t*)0x2001a009 = (uint8_t)0x0; *(uint8_t*)0x2001a00a = (uint8_t)0x0; *(uint8_t*)0x2001a00b = (uint8_t)0x0; *(uint8_t*)0x2001a00c = (uint8_t)0x0; *(uint8_t*)0x2001a00d = (uint8_t)0x0; *(uint8_t*)0x2001a00e = (uint8_t)0x0; *(uint8_t*)0x2001a00f = (uint8_t)0x0; *(uint8_t*)0x2001a010 = (uint8_t)0xfe; *(uint8_t*)0x2001a011 = (uint8_t)0x80; *(uint8_t*)0x2001a012 = (uint8_t)0x0; *(uint8_t*)0x2001a013 = (uint8_t)0x0; *(uint8_t*)0x2001a014 = (uint8_t)0x0; *(uint8_t*)0x2001a015 = (uint8_t)0x0; *(uint8_t*)0x2001a016 = (uint8_t)0x0; *(uint8_t*)0x2001a017 = (uint8_t)0x0; *(uint8_t*)0x2001a018 = (uint8_t)0x0; *(uint8_t*)0x2001a019 = (uint8_t)0x0; *(uint8_t*)0x2001a01a = (uint8_t)0x0; *(uint8_t*)0x2001a01b = (uint8_t)0x0; *(uint8_t*)0x2001a01c = (uint8_t)0x0; *(uint8_t*)0x2001a01d = (uint8_t)0x0; *(uint8_t*)0x2001a01e = (uint8_t)0x0; *(uint8_t*)0x2001a01f = (uint8_t)0xbb; *(uint16_t*)0x2001a020 = (uint16_t)0x204e; *(uint16_t*)0x2001a022 = (uint16_t)0x40000000000000; *(uint16_t*)0x2001a024 = (uint16_t)0x204e; *(uint16_t*)0x2001a026 = (uint16_t)0x0; *(uint16_t*)0x2001a028 = (uint16_t)0xa; *(uint8_t*)0x2001a02a = (uint8_t)0x0; *(uint8_t*)0x2001a02b = (uint8_t)0x0; *(uint8_t*)0x2001a02c = (uint8_t)0x0; *(uint32_t*)0x2001a030 = (uint32_t)0x0; *(uint32_t*)0x2001a034 = (uint32_t)0x0; *(uint64_t*)0x2001a038 = (uint64_t)0x0; *(uint64_t*)0x2001a040 = (uint64_t)0xfffffffffffffffe; *(uint64_t*)0x2001a048 = (uint64_t)0x8; *(uint64_t*)0x2001a050 = (uint64_t)0x0; *(uint64_t*)0x2001a058 = (uint64_t)0x1; *(uint64_t*)0x2001a060 = (uint64_t)0x0; *(uint64_t*)0x2001a068 = (uint64_t)0x0; *(uint64_t*)0x2001a070 = (uint64_t)0x0; *(uint64_t*)0x2001a078 = (uint64_t)0x5; *(uint64_t*)0x2001a080 = (uint64_t)0x4; *(uint64_t*)0x2001a088 = (uint64_t)0x0; *(uint64_t*)0x2001a090 = (uint64_t)0x0; *(uint32_t*)0x2001a098 = (uint32_t)0x0; *(uint32_t*)0x2001a09c = (uint32_t)0x0; *(uint8_t*)0x2001a0a0 = (uint8_t)0x1; *(uint8_t*)0x2001a0a1 = (uint8_t)0x0; *(uint8_t*)0x2001a0a2 = (uint8_t)0x0; *(uint8_t*)0x2001a0a3 = (uint8_t)0x0; *(uint8_t*)0x2001a0a8 = (uint8_t)0xfe; *(uint8_t*)0x2001a0a9 = (uint8_t)0x80; *(uint8_t*)0x2001a0aa = (uint8_t)0x0; *(uint8_t*)0x2001a0ab = (uint8_t)0x0; *(uint8_t*)0x2001a0ac = (uint8_t)0x0; *(uint8_t*)0x2001a0ad = (uint8_t)0x0; *(uint8_t*)0x2001a0ae = (uint8_t)0x0; *(uint8_t*)0x2001a0af = (uint8_t)0x0; *(uint8_t*)0x2001a0b0 = (uint8_t)0x0; *(uint8_t*)0x2001a0b1 = (uint8_t)0x0; *(uint8_t*)0x2001a0b2 = (uint8_t)0x0; *(uint8_t*)0x2001a0b3 = (uint8_t)0x0; *(uint8_t*)0x2001a0b4 = (uint8_t)0x0; *(uint8_t*)0x2001a0b5 = (uint8_t)0x0; *(uint8_t*)0x2001a0b6 = (uint8_t)0x0; *(uint8_t*)0x2001a0b7 = (uint8_t)0xaa; *(uint32_t*)0x2001a0b8 = (uint32_t)0x0; *(uint8_t*)0x2001a0bc = (uint8_t)0x0; *(uint16_t*)0x2001a0c0 = (uint16_t)0x0; *(uint8_t*)0x2001a0c4 = (uint8_t)0xac; *(uint8_t*)0x2001a0c5 = (uint8_t)0x14; *(uint8_t*)0x2001a0c6 = (uint8_t)0x0; *(uint8_t*)0x2001a0c7 = (uint8_t)0xbb; *(uint32_t*)0x2001a0d4 = (uint32_t)0x0; *(uint8_t*)0x2001a0d8 = (uint8_t)0x0; *(uint8_t*)0x2001a0d9 = (uint8_t)0x0; *(uint8_t*)0x2001a0da = (uint8_t)0x0; *(uint32_t*)0x2001a0dc = (uint32_t)0x81; *(uint32_t*)0x2001a0e0 = (uint32_t)0x81; *(uint32_t*)0x2001a0e4 = (uint32_t)0xd746; r[145] = syscall(__NR_setsockopt, r[1], 0x0ul, 0x11ul, 0x2001a000ul, 0xe8ul); break; } return 0; } void loop() { long i; pthread_t th[12]; memset(r, -1, sizeof(r)); srand(getpid()); for (i = 0; i < 6; i++) { pthread_create(&th[i], 0, thr, (void*)i); usleep(rand() % 10000); } for (i = 0; i < 6; i++) { pthread_create(&th[6 + i], 0, thr, (void*)i); if (rand() % 2) usleep(rand() % 10000); } usleep(rand() % 100000); } int main() { setup_tun(0, true); loop(); return 0; }