// https://syzkaller.appspot.com/bug?id=6dcd14a729df98f989c7b76d254226ae67084efd // 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 __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 uintptr_t syz_open_dev(uintptr_t a0, uintptr_t a1, uintptr_t a2) { if (a0 == 0xc || a0 == 0xb) { char buf[128]; sprintf(buf, "/dev/%s/%d:%d", a0 == 0xc ? "char" : "block", (uint8_t)a1, (uint8_t)a2); return open(buf, O_RDWR, 0); } else { char buf[1024]; char* hash; strncpy(buf, (char*)a0, sizeof(buf)); buf[sizeof(buf) - 1] = 0; while ((hash = strchr(buf, '#'))) { *hash = '0' + (char)(a1 % 10); a1 /= 10; } return open(buf, a2, 0); } } 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(int executor_pid, bool enable_tun) { if (unshare(CLONE_NEWPID)) { } int pid = fork(); if (pid < 0) fail("sandbox fork failed"); if (pid) return pid; sandbox_common(); if (unshare(CLONE_NEWNET)) { } 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 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); 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; } } } } long r[1]; uint64_t procid; void execute_call(int call) { switch (call) { case 0: syscall(__NR_mmap, 0x20000000, 0xfff000, 3, 0x32, -1, 0); break; case 1: memcpy((void*)0x20d72ff7, "/dev/sg#", 9); r[0] = syz_open_dev(0x20d72ff7, 0, 0x2000000002); break; case 2: *(uint8_t*)0x205b9f9d = 0; *(uint8_t*)0x205b9f9e = 0; *(uint16_t*)0x205b9f9f = 0; *(uint16_t*)0x205b9fa1 = 0; *(uint16_t*)0x205b9fa3 = 0; *(uint16_t*)0x205b9fa5 = 0; STORE_BY_BITMASK(uint8_t, 0x205b9fa7, 5, 0, 4); STORE_BY_BITMASK(uint8_t, 0x205b9fa7, 4, 4, 4); STORE_BY_BITMASK(uint8_t, 0x205b9fa8, 0, 0, 2); STORE_BY_BITMASK(uint8_t, 0x205b9fa8, 0, 2, 6); *(uint16_t*)0x205b9fa9 = htobe16(0x24); *(uint16_t*)0x205b9fab = 0; *(uint16_t*)0x205b9fad = htobe16(0); *(uint8_t*)0x205b9faf = 0; *(uint8_t*)0x205b9fb0 = 0; *(uint16_t*)0x205b9fb1 = 0; *(uint32_t*)0x205b9fb3 = htobe32(0xe0000002); *(uint32_t*)0x205b9fb7 = htobe32(0xe0000001); *(uint16_t*)0x205b9fbb = htobe16(0x4e22 + procid * 4); *(uint16_t*)0x205b9fbd = htobe16(0x4e22 + procid * 4); *(uint8_t*)0x205b9fbf = 4; STORE_BY_BITMASK(uint8_t, 0x205b9fc0, 1, 0, 4); STORE_BY_BITMASK(uint8_t, 0x205b9fc0, 0, 4, 4); *(uint16_t*)0x205b9fc1 = 0; STORE_BY_BITMASK(uint8_t, 0x205b9fc3, 0, 0, 1); STORE_BY_BITMASK(uint8_t, 0x205b9fc3, 0xf, 1, 4); STORE_BY_BITMASK(uint8_t, 0x205b9fc3, 0, 5, 3); memcpy((void*)0x205b9fc4, "\x94\x51\x54", 3); *(uint8_t*)0x205b9fc7 = 0; memcpy((void*)0x205b9fc8, "\xfd\x64\x18", 3); struct csum_inet csum_1; csum_inet_init(&csum_1); csum_inet_update(&csum_1, (const uint8_t*)0x205b9fb3, 4); csum_inet_update(&csum_1, (const uint8_t*)0x205b9fb7, 4); uint16_t csum_1_chunk_2 = 0x2100; csum_inet_update(&csum_1, (const uint8_t*)&csum_1_chunk_2, 2); uint16_t csum_1_chunk_3 = 0x1000; csum_inet_update(&csum_1, (const uint8_t*)&csum_1_chunk_3, 2); csum_inet_update(&csum_1, (const uint8_t*)0x205b9fbb, 16); *(uint16_t*)0x205b9fc1 = csum_inet_digest(&csum_1); struct csum_inet csum_2; csum_inet_init(&csum_2); csum_inet_update(&csum_2, (const uint8_t*)0x205b9fa7, 20); *(uint16_t*)0x205b9fb1 = csum_inet_digest(&csum_2); syscall(__NR_write, r[0], 0x205b9f9d, 0x2e); break; case 3: *(uint64_t*)0x203f8f70 = 0x20adff12; *(uint64_t*)0x203f8f78 = 0x177; syscall(__NR_readv, r[0], 0x203f8f70, 1); break; } } void test() { memset(r, -1, sizeof(r)); execute(4); } int main() { for (procid = 0; procid < 8; procid++) { if (fork() == 0) { for (;;) { int pid = do_sandbox_none(procid, false); int status = 0; while (waitpid(pid, &status, __WALL) != pid) { } } } } sleep(1000000); return 0; }