// https://syzkaller.appspot.com/bug?id=f99edaeec58ad40380ed5813d89e205861be2896 // 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 __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(bool panic, 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 (panic && 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 TUN_IFACE "syz_tun" #define LOCAL_MAC "aa:aa:aa:aa:aa:aa" #define REMOTE_MAC "aa:aa:aa:aa:aa:bb" #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 = 252; if (dup2(tunfd, kTunFd) < 0) fail("dup2(tunfd, kTunFd) failed"); 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) 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; execute_command(1, "sysctl -w net.ipv6.conf.%s.accept_dad=0", TUN_IFACE); execute_command(1, "sysctl -w net.ipv6.conf.%s.router_solicitations=0", TUN_IFACE); execute_command(1, "ip link set dev %s address %s", TUN_IFACE, LOCAL_MAC); execute_command(1, "ip addr add %s/24 dev %s", LOCAL_IPV4, TUN_IFACE); execute_command(1, "ip -6 addr add %s/120 dev %s", LOCAL_IPV6, TUN_IFACE); execute_command(1, "ip neigh add %s lladdr %s dev %s nud permanent", REMOTE_IPV4, REMOTE_MAC, TUN_IFACE); execute_command(1, "ip -6 neigh add %s lladdr %s dev %s nud permanent", REMOTE_IPV6, REMOTE_MAC, TUN_IFACE); execute_command(1, "ip link set dev %s up", TUN_IFACE); } #define DEV_IPV4 "172.20.20.%d" #define DEV_IPV6 "fe80::%02hx" #define DEV_MAC "aa:aa:aa:aa:aa:%02hx" static void initialize_netdevices(void) { unsigned i; const char* devtypes[] = {"ip6gretap", "bridge", "vcan", "bond", "veth"}; const char* devnames[] = {"lo", "sit0", "bridge0", "vcan0", "tunl0", "gre0", "gretap0", "ip_vti0", "ip6_vti0", "ip6tnl0", "ip6gre0", "ip6gretap0", "erspan0", "bond0", "veth0", "veth1"}; for (i = 0; i < sizeof(devtypes) / (sizeof(devtypes[0])); i++) execute_command(0, "ip link add dev %s0 type %s", devtypes[i], devtypes[i]); execute_command(0, "ip link add dev veth1 type veth"); for (i = 0; i < sizeof(devnames) / (sizeof(devnames[0])); i++) { char addr[32]; snprintf_check(addr, sizeof(addr), DEV_IPV4, i + 10); execute_command(0, "ip -4 addr add %s/24 dev %s", addr, devnames[i]); snprintf_check(addr, sizeof(addr), DEV_IPV6, i + 10); execute_command(0, "ip -6 addr add %s/120 dev %s", addr, devnames[i]); snprintf_check(addr, sizeof(addr), DEV_MAC, i + 10); execute_command(0, "ip link set dev %s address %s", devnames[i], addr); execute_command(0, "ip link set dev %s up", devnames[i]); } } #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); } 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); #define CLONE_NEWCGROUP 0x02000000 if (unshare(CLONE_NEWNS)) { } if (unshare(CLONE_NEWIPC)) { } if (unshare(CLONE_NEWCGROUP)) { } if (unshare(CLONE_NEWUTS)) { } if (unshare(CLONE_SYSVSEM)) { } } static int do_sandbox_none(void) { if (unshare(CLONE_NEWPID)) { } int pid = fork(); if (pid < 0) fail("sandbox fork failed"); if (pid) return pid; sandbox_common(); if (unshare(CLONE_NEWNET)) { } initialize_tun(); initialize_netdevices(); loop(); doexit(1); } static void test(); void loop() { while (1) { test(); } } struct thread_t { int created, running, call; pthread_t th; }; static struct thread_t threads[16]; static void execute_call(int call); static int running; static int collide; static void* thr(void* arg) { struct thread_t* th = (struct thread_t*)arg; for (;;) { while (!__atomic_load_n(&th->running, __ATOMIC_ACQUIRE)) syscall(SYS_futex, &th->running, FUTEX_WAIT, 0, 0); execute_call(th->call); __atomic_fetch_sub(&running, 1, __ATOMIC_RELAXED); __atomic_store_n(&th->running, 0, __ATOMIC_RELEASE); syscall(SYS_futex, &th->running, FUTEX_WAKE); } return 0; } static void execute(int num_calls) { int call, thread; running = 0; for (call = 0; call < num_calls; call++) { for (thread = 0; thread < sizeof(threads) / sizeof(threads[0]); thread++) { struct thread_t* th = &threads[thread]; if (!th->created) { th->created = 1; pthread_attr_t attr; pthread_attr_init(&attr); pthread_attr_setstacksize(&attr, 128 << 10); pthread_create(&th->th, &attr, thr, th); } if (!__atomic_load_n(&th->running, __ATOMIC_ACQUIRE)) { th->call = call; __atomic_fetch_add(&running, 1, __ATOMIC_RELAXED); __atomic_store_n(&th->running, 1, __ATOMIC_RELEASE); syscall(SYS_futex, &th->running, FUTEX_WAKE); if (collide && call % 2) break; struct timespec ts; ts.tv_sec = 0; ts.tv_nsec = 20 * 1000 * 1000; syscall(SYS_futex, &th->running, FUTEX_WAIT, 1, &ts); if (running) usleep((call == num_calls - 1) ? 10000 : 1000); break; } } } } uint64_t r[3] = {0xffffffffffffffff, 0xffffffffffffffff, 0xffffffffffffffff}; uint64_t procid; void execute_call(int call) { long res; switch (call) { case 0: res = syscall(__NR_socket, 0xa, 2, 0); if (res != -1) r[0] = res; break; case 1: memcpy((void*)0x200004c0, "\x66\x69\x6c\x74\x65\x72\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x0e\x00\x00\x00\x04\x00\x00\x00\xae\xcd\x75\x26\x6d\x05\xd8\x03" "\x00\x00\xff\xff\xff\xff\xf0\x00\x00\x00\xf0\x00\x00\x00\xf0\x00" "\x00\x00\xff\xff\xff\xff\xff\xff\xff\x87\xe7\x28\xff\x08\x03\x00" "\x00\x08\x03\x00\x00\x08\x03\x00\x00\xff\xff", 91); *(uint64_t*)0x2000051b = 0x20000040; syscall(__NR_setsockopt, r[0], 0x29, 0x40, 0x200004c0, 3); break; case 2: memcpy((void*)0x203e4f72, "\xcd\x39\x0b\x08\x1b\xf2", 6); *(uint8_t*)0x203e4f78 = -1; *(uint8_t*)0x203e4f79 = -1; *(uint8_t*)0x203e4f7a = -1; *(uint8_t*)0x203e4f7b = -1; *(uint8_t*)0x203e4f7c = -1; *(uint8_t*)0x203e4f7d = -1; *(uint16_t*)0x203e4f7e = htobe16(0x86dd); STORE_BY_BITMASK(uint8_t, 0x203e4f80, 0, 0, 4); STORE_BY_BITMASK(uint8_t, 0x203e4f80, 6, 4, 4); memcpy((void*)0x203e4f81, "\x0f\x29\x02", 3); *(uint16_t*)0x203e4f84 = htobe16(8); *(uint8_t*)0x203e4f86 = 0x3a; *(uint8_t*)0x203e4f87 = 0; *(uint8_t*)0x203e4f88 = 0; *(uint8_t*)0x203e4f89 = 0; *(uint8_t*)0x203e4f8a = 0; *(uint8_t*)0x203e4f8b = 0; *(uint8_t*)0x203e4f8c = 0; *(uint8_t*)0x203e4f8d = 0; *(uint8_t*)0x203e4f8e = 0; *(uint8_t*)0x203e4f8f = 0; *(uint8_t*)0x203e4f90 = 0; *(uint8_t*)0x203e4f91 = 0; *(uint8_t*)0x203e4f92 = -1; *(uint8_t*)0x203e4f93 = -1; *(uint32_t*)0x203e4f94 = htobe32(0); *(uint8_t*)0x203e4f98 = 0xfe; *(uint8_t*)0x203e4f99 = 0x80; *(uint8_t*)0x203e4f9a = 0; *(uint8_t*)0x203e4f9b = 0; *(uint8_t*)0x203e4f9c = 0; *(uint8_t*)0x203e4f9d = 0; *(uint8_t*)0x203e4f9e = 0; *(uint8_t*)0x203e4f9f = 0; *(uint8_t*)0x203e4fa0 = 0; *(uint8_t*)0x203e4fa1 = 0; *(uint8_t*)0x203e4fa2 = 0; *(uint8_t*)0x203e4fa3 = 0; *(uint8_t*)0x203e4fa4 = 0; *(uint8_t*)0x203e4fa5 = 0; *(uint8_t*)0x203e4fa6 = 0; *(uint8_t*)0x203e4fa7 = 0; *(uint16_t*)0x203e4fa8 = htobe16(0x4e20); *(uint16_t*)0x203e4faa = htobe16(0x4e20); *(uint16_t*)0x203e4fac = htobe16(8); *(uint16_t*)0x203e4fae = 0; struct csum_inet csum_1; csum_inet_init(&csum_1); csum_inet_update(&csum_1, (const uint8_t*)0x203e4f88, 16); csum_inet_update(&csum_1, (const uint8_t*)0x203e4f98, 16); uint32_t csum_1_chunk_2 = 0x8000000; csum_inet_update(&csum_1, (const uint8_t*)&csum_1_chunk_2, 4); uint32_t csum_1_chunk_3 = 0x11000000; csum_inet_update(&csum_1, (const uint8_t*)&csum_1_chunk_3, 4); csum_inet_update(&csum_1, (const uint8_t*)0x203e4fa8, 8); *(uint16_t*)0x203e4fae = csum_inet_digest(&csum_1); syz_emit_ethernet(0x3e, 0x203e4f72, 0); break; case 3: res = syscall(__NR_socket, 0xa, 2, 0); if (res != -1) r[1] = res; break; case 4: res = syscall(__NR_socket, 0x10, 3, 6); if (res != -1) r[2] = res; break; case 5: *(uint16_t*)0x20c63ff4 = 0x10; *(uint16_t*)0x20c63ff6 = 0; *(uint32_t*)0x20c63ff8 = 0; *(uint32_t*)0x20c63ffc = 3; syscall(__NR_bind, r[2], 0x20c63ff4, 0xc); break; case 6: *(uint16_t*)0x2052f000 = 0xa; *(uint16_t*)0x2052f002 = htobe16(0x4e20); *(uint32_t*)0x2052f004 = 0; *(uint8_t*)0x2052f008 = -1; *(uint8_t*)0x2052f009 = 2; *(uint8_t*)0x2052f00a = 0; *(uint8_t*)0x2052f00b = 0; *(uint8_t*)0x2052f00c = 0; *(uint8_t*)0x2052f00d = 0; *(uint8_t*)0x2052f00e = 0; *(uint8_t*)0x2052f00f = 0; *(uint8_t*)0x2052f010 = 0; *(uint8_t*)0x2052f011 = 0; *(uint8_t*)0x2052f012 = 0; *(uint8_t*)0x2052f013 = 0; *(uint8_t*)0x2052f014 = 0; *(uint8_t*)0x2052f015 = 0; *(uint8_t*)0x2052f016 = 0; *(uint8_t*)0x2052f017 = 1; *(uint32_t*)0x2052f018 = 7; syscall(__NR_connect, r[1], 0x2052f000, 0x1c); break; case 7: *(uint32_t*)0x20c9af18 = htobe32(0); *(uint8_t*)0x20c9af28 = 0xfe; *(uint8_t*)0x20c9af29 = 0x80; *(uint8_t*)0x20c9af2a = 0; *(uint8_t*)0x20c9af2b = 0; *(uint8_t*)0x20c9af2c = 0; *(uint8_t*)0x20c9af2d = 0; *(uint8_t*)0x20c9af2e = 0; *(uint8_t*)0x20c9af2f = 0; *(uint8_t*)0x20c9af30 = 0; *(uint8_t*)0x20c9af31 = 0; *(uint8_t*)0x20c9af32 = 0; *(uint8_t*)0x20c9af33 = 0; *(uint8_t*)0x20c9af34 = 0; *(uint8_t*)0x20c9af35 = 0; *(uint8_t*)0x20c9af36 = 0; *(uint8_t*)0x20c9af37 = 0; *(uint16_t*)0x20c9af38 = htobe16(0x4e20); *(uint16_t*)0x20c9af3a = htobe16(0); *(uint16_t*)0x20c9af3c = htobe16(0x4e20); *(uint16_t*)0x20c9af3e = htobe16(0); *(uint16_t*)0x20c9af40 = 0xa; *(uint8_t*)0x20c9af42 = 0; *(uint8_t*)0x20c9af43 = 0; *(uint8_t*)0x20c9af44 = 0; *(uint32_t*)0x20c9af48 = 0; *(uint32_t*)0x20c9af4c = 0; *(uint64_t*)0x20c9af50 = 0; *(uint64_t*)0x20c9af58 = 0; *(uint64_t*)0x20c9af60 = 0; *(uint64_t*)0x20c9af68 = 0; *(uint64_t*)0x20c9af70 = 0; *(uint64_t*)0x20c9af78 = 0; *(uint64_t*)0x20c9af80 = 0; *(uint64_t*)0x20c9af88 = 0; *(uint64_t*)0x20c9af90 = 0; *(uint64_t*)0x20c9af98 = 0; *(uint64_t*)0x20c9afa0 = 0; *(uint64_t*)0x20c9afa8 = 0; *(uint32_t*)0x20c9afb0 = 0; *(uint32_t*)0x20c9afb4 = 0; *(uint8_t*)0x20c9afb8 = 1; *(uint8_t*)0x20c9afb9 = 0; *(uint8_t*)0x20c9afba = 0; *(uint8_t*)0x20c9afbb = 0; *(uint32_t*)0x20c9afc0 = htobe32(0xe0000002); *(uint32_t*)0x20c9afd0 = htobe32(0); *(uint8_t*)0x20c9afd4 = 0x3c; *(uint16_t*)0x20c9afd8 = 0; *(uint8_t*)0x20c9afdc = 0; *(uint8_t*)0x20c9afdd = 0; *(uint8_t*)0x20c9afde = 0; *(uint8_t*)0x20c9afdf = 0; *(uint8_t*)0x20c9afe0 = 0; *(uint8_t*)0x20c9afe1 = 0; *(uint8_t*)0x20c9afe2 = 0; *(uint8_t*)0x20c9afe3 = 0; *(uint8_t*)0x20c9afe4 = 0; *(uint8_t*)0x20c9afe5 = 0; *(uint8_t*)0x20c9afe6 = -1; *(uint8_t*)0x20c9afe7 = -1; *(uint8_t*)0x20c9afe8 = 0xac; *(uint8_t*)0x20c9afe9 = 0x14; *(uint8_t*)0x20c9afea = -1; *(uint8_t*)0x20c9afeb = 0xbb; *(uint32_t*)0x20c9afec = 0; *(uint8_t*)0x20c9aff0 = 0; *(uint8_t*)0x20c9aff1 = 0; *(uint8_t*)0x20c9aff2 = 0xfd; *(uint32_t*)0x20c9aff4 = 0; *(uint32_t*)0x20c9aff8 = 0; *(uint32_t*)0x20c9affc = 0; syscall(__NR_setsockopt, r[1], 0x29, 0x23, 0x20c9af18, 0xe8); break; case 8: *(uint64_t*)0x200024c0 = 0; *(uint32_t*)0x200024c8 = 0; *(uint64_t*)0x200024d0 = 0x20002400; *(uint64_t*)0x200024d8 = 0; *(uint64_t*)0x200024e0 = 0; *(uint64_t*)0x200024e8 = 0; *(uint32_t*)0x200024f0 = 0; syscall(__NR_sendmsg, r[1], 0x200024c0, 0); break; } } void test() { execute(9); collide = 1; execute(9); } int main() { syscall(__NR_mmap, 0x20000000, 0x1000000, 3, 0x32, -1, 0); for (procid = 0; procid < 8; procid++) { if (fork() == 0) { for (;;) { int pid = do_sandbox_none(); int status = 0; while (waitpid(pid, &status, __WALL) != pid) { } } } } sleep(1000000); return 0; }