// https://syzkaller.appspot.com/bug?id=f62d236e2fceaeb104f4e8f77d2324ef9da4b41b // 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 __attribute__((noreturn)) static void doexit(int status) { volatile unsigned i; syscall(__NR_exit_group, status); for (i = 0;; i++) { } } #include #include #include #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); va_end(args); rv = system(command); if (rv) { if (panic) fail("command '%s' failed: %d", &command[0], rv); } } 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", "team"}; const char* devnames[] = {"lo", "sit0", "bridge0", "vcan0", "tunl0", "gre0", "gretap0", "ip_vti0", "ip6_vti0", "ip6tnl0", "ip6gre0", "ip6gretap0", "erspan0", "bond0", "veth0", "veth1", "team0", "veth0_to_bridge", "veth1_to_bridge", "veth0_to_bond", "veth1_to_bond", "veth0_to_team", "veth1_to_team"}; const char* devmasters[] = {"bridge", "bond", "team"}; 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 type veth"); for (i = 0; i < sizeof(devmasters) / (sizeof(devmasters[0])); i++) { execute_command( 0, "ip link add name %s_slave_0 type veth peer name veth0_to_%s", devmasters[i], devmasters[i]); execute_command( 0, "ip link add name %s_slave_1 type veth peer name veth1_to_%s", devmasters[i], devmasters[i]); execute_command(0, "ip link set %s_slave_0 master %s0", devmasters[i], devmasters[i]); execute_command(0, "ip link set %s_slave_1 master %s0", devmasters[i], devmasters[i]); execute_command(0, "ip link set veth0_to_%s up", devmasters[i]); execute_command(0, "ip link set veth1_to_%s up", devmasters[i]); } execute_command(0, "ip link set bridge_slave_0 up"); execute_command(0, "ip link set bridge_slave_1 up"); 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 = 160 << 20; setrlimit(RLIMIT_AS, &rlim); rlim.rlim_cur = rlim.rlim_max = 8 << 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); if (unshare(CLONE_NEWNS)) { } if (unshare(CLONE_NEWIPC)) { } if (unshare(0x02000000)) { } 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); } uint64_t r[1] = {0xffffffffffffffff}; void loop() { long res = 0; *(uint8_t*)0x20015e15 = -1; *(uint8_t*)0x20015e16 = -1; *(uint8_t*)0x20015e17 = -1; *(uint8_t*)0x20015e18 = -1; *(uint8_t*)0x20015e19 = -1; *(uint8_t*)0x20015e1a = -1; *(uint8_t*)0x20015e1b = 0xaa; *(uint8_t*)0x20015e1c = 0xaa; *(uint8_t*)0x20015e1d = 0xaa; *(uint8_t*)0x20015e1e = 0xaa; *(uint8_t*)0x20015e1f = 0; *(uint8_t*)0x20015e20 = -1; *(uint16_t*)0x20015e21 = htobe16(0x86dd); STORE_BY_BITMASK(uint8_t, 0x20015e23, 0, 0, 4); STORE_BY_BITMASK(uint8_t, 0x20015e23, 6, 4, 4); memcpy((void*)0x20015e24, "v`Q", 3); *(uint16_t*)0x20015e27 = htobe16(0x30); *(uint8_t*)0x20015e29 = 0x3a; *(uint8_t*)0x20015e2a = -1; *(uint8_t*)0x20015e2b = 0xfe; *(uint8_t*)0x20015e2c = 0x80; *(uint8_t*)0x20015e2d = 0; *(uint8_t*)0x20015e2e = 0; *(uint8_t*)0x20015e2f = 0; *(uint8_t*)0x20015e30 = 0; *(uint8_t*)0x20015e31 = 0; *(uint8_t*)0x20015e32 = 0; *(uint8_t*)0x20015e33 = 0; *(uint8_t*)0x20015e34 = 0; *(uint8_t*)0x20015e35 = 0; *(uint8_t*)0x20015e36 = 0; *(uint8_t*)0x20015e37 = 0; *(uint8_t*)0x20015e38 = 0; *(uint8_t*)0x20015e39 = 0; *(uint8_t*)0x20015e3a = -1; *(uint8_t*)0x20015e3b = -1; *(uint8_t*)0x20015e3c = 2; *(uint8_t*)0x20015e3d = 0; *(uint8_t*)0x20015e3e = 0; *(uint8_t*)0x20015e3f = 0; *(uint8_t*)0x20015e40 = 0; *(uint8_t*)0x20015e41 = 0; *(uint8_t*)0x20015e42 = 0; *(uint8_t*)0x20015e43 = 0; *(uint8_t*)0x20015e44 = 0; *(uint8_t*)0x20015e45 = 0; *(uint8_t*)0x20015e46 = 0; *(uint8_t*)0x20015e47 = 0; *(uint8_t*)0x20015e48 = 0; *(uint8_t*)0x20015e49 = 0; *(uint8_t*)0x20015e4a = 1; *(uint8_t*)0x20015e4b = 0x89; *(uint8_t*)0x20015e4c = 0; *(uint16_t*)0x20015e4d = 0; *(uint8_t*)0x20015e4f = 0; *(uint8_t*)0x20015e50 = 0x14; *(uint8_t*)0x20015e51 = 0; *(uint8_t*)0x20015e52 = 0; STORE_BY_BITMASK(uint8_t, 0x20015e53, 0, 0, 4); STORE_BY_BITMASK(uint8_t, 0x20015e53, 6, 4, 4); memcpy((void*)0x20015e54, "\xc5\x96\x1e", 3); *(uint16_t*)0x20015e57 = htobe16(0); *(uint8_t*)0x20015e59 = 0; *(uint8_t*)0x20015e5a = 0; *(uint8_t*)0x20015e5b = -1; *(uint8_t*)0x20015e5c = 1; *(uint8_t*)0x20015e5d = 0; *(uint8_t*)0x20015e5e = 0; *(uint8_t*)0x20015e5f = 0; *(uint8_t*)0x20015e60 = 0; *(uint8_t*)0x20015e61 = 0; *(uint8_t*)0x20015e62 = 0; *(uint8_t*)0x20015e63 = 0x18; *(uint8_t*)0x20015e64 = 3; *(uint8_t*)0x20015e65 = 0; *(uint8_t*)0x20015e66 = 0; *(uint8_t*)0x20015e67 = 0; *(uint8_t*)0x20015e68 = 0; *(uint8_t*)0x20015e69 = 0; *(uint8_t*)0x20015e6a = 1; *(uint8_t*)0x20015e6b = -1; *(uint8_t*)0x20015e6c = 2; *(uint8_t*)0x20015e6d = 0; *(uint8_t*)0x20015e6e = 0; *(uint8_t*)0x20015e6f = 0; *(uint8_t*)0x20015e70 = 0; *(uint8_t*)0x20015e71 = 0; *(uint8_t*)0x20015e72 = 0; *(uint8_t*)0x20015e73 = 0; *(uint8_t*)0x20015e74 = 0; *(uint8_t*)0x20015e75 = 0; *(uint8_t*)0x20015e76 = 0; *(uint8_t*)0x20015e77 = 0; *(uint8_t*)0x20015e78 = 0; *(uint8_t*)0x20015e79 = 0; *(uint8_t*)0x20015e7a = 1; struct csum_inet csum_1; csum_inet_init(&csum_1); csum_inet_update(&csum_1, (const uint8_t*)0x20015e2b, 16); csum_inet_update(&csum_1, (const uint8_t*)0x20015e3b, 16); uint32_t csum_1_chunk_2 = 0x30000000; csum_inet_update(&csum_1, (const uint8_t*)&csum_1_chunk_2, 4); uint32_t csum_1_chunk_3 = 0x3a000000; csum_inet_update(&csum_1, (const uint8_t*)&csum_1_chunk_3, 4); csum_inet_update(&csum_1, (const uint8_t*)0x20015e4b, 48); *(uint16_t*)0x20015e4d = csum_inet_digest(&csum_1); syz_emit_ethernet(0x66, 0x20015e15, 0); res = syscall(__NR_socket, 0x11, 0x4000000000080003, 0); if (res != -1) r[0] = res; *(uint64_t*)0x20003e80 = 0x20000040; *(uint16_t*)0x20000040 = 0xa; *(uint16_t*)0x20000042 = htobe16(0); *(uint32_t*)0x20000044 = 3; *(uint8_t*)0x20000048 = -1; *(uint8_t*)0x20000049 = 1; *(uint8_t*)0x2000004a = 0; *(uint8_t*)0x2000004b = 0; *(uint8_t*)0x2000004c = 0; *(uint8_t*)0x2000004d = 0; *(uint8_t*)0x2000004e = 0; *(uint8_t*)0x2000004f = 0; *(uint8_t*)0x20000050 = 0; *(uint8_t*)0x20000051 = 0; *(uint8_t*)0x20000052 = 0; *(uint8_t*)0x20000053 = 0; *(uint8_t*)0x20000054 = 0; *(uint8_t*)0x20000055 = 0; *(uint8_t*)0x20000056 = 0; *(uint8_t*)0x20000057 = 1; *(uint32_t*)0x20000058 = 0; *(uint32_t*)0x20003e88 = 0x1c; *(uint64_t*)0x20003e90 = 0x20000300; *(uint64_t*)0x20003e98 = 0; *(uint64_t*)0x20003ea0 = 0x20000140; *(uint64_t*)0x20003ea8 = 0; *(uint32_t*)0x20003eb0 = 0; *(uint32_t*)0x20003eb8 = 0; *(uint64_t*)0x20003ec0 = 0x20000e80; *(uint16_t*)0x20000e80 = 4; *(uint16_t*)0x20000e82 = htobe16(0); *(uint32_t*)0x20000e84 = htobe32(0); memcpy((void*)0x20000e88, "\x85\x01\x6d\xfe\x9b\x78", 6); *(uint8_t*)0x20000e8e = 0; *(uint8_t*)0x20000e8f = 0; *(uint32_t*)0x20003ec8 = 0x20000e90; *(uint64_t*)0x20003ed0 = 0x20000f80; *(uint64_t*)0x20003ed8 = 0; *(uint64_t*)0x20003ee0 = 0x20002480; *(uint64_t*)0x20003ee8 = 0; *(uint32_t*)0x20003ef0 = 0; *(uint32_t*)0x20003ef8 = 0; syscall(__NR_sendmmsg, r[0], 0x20003e80, 2, 0); } int main() { syscall(__NR_mmap, 0x20000000, 0x1000000, 3, 0x32, -1, 0); int pid = do_sandbox_none(); int status = 0; while (waitpid(pid, &status, __WALL) != pid) { } return 0; }