// https://syzkaller.appspot.com/bug?id=a5cbfef4c4ab02f7d63f18f9c3b36812c4d2cc9b // autogenerated by syzkaller (http://github.com/google/syzkaller) #define _GNU_SOURCE #include #include #include #include #include #include #include #include #include #include #include #include #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 uintptr_t syz_fuse_mount(uintptr_t a0, uintptr_t a1, uintptr_t a2, uintptr_t a3, uintptr_t a4, uintptr_t a5) { uint64_t target = a0; uint64_t mode = a1; uint64_t uid = a2; uint64_t gid = a3; uint64_t maxread = a4; uint64_t flags = a5; int fd = open("/dev/fuse", O_RDWR); if (fd == -1) return fd; char buf[1024]; sprintf(buf, "fd=%d,user_id=%ld,group_id=%ld,rootmode=0%o", fd, (long)uid, (long)gid, (unsigned)mode & ~3u); if (maxread != 0) sprintf(buf + strlen(buf), ",max_read=%ld", (long)maxread); if (mode & 1) strcat(buf, ",default_permissions"); if (mode & 2) strcat(buf, ",allow_other"); syscall(SYS_mount, "", target, "fuse", flags, buf); return fd; } 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; } } } } uint64_t r[1] = {0xffffffffffffffff}; void execute_call(int call) { long res; switch (call) { case 0: memcpy((void*)0x20000840, "./file0", 8); syscall(__NR_mknod, 0x20000840, 0, 0); break; case 1: memcpy((void*)0x20000080, "./file0", 8); res = syz_fuse_mount(0x20000080, 0x8000, 0, 0, 0, 0); if (res != -1) r[0] = res; break; case 2: memcpy((void*)0x20000000, "./file0", 8); syscall(__NR_mkdir, 0x20000000, 0); break; case 3: *(uint32_t*)0x2000a000 = 6; *(uint32_t*)0x2000a004 = 0x78; *(uint8_t*)0x2000a008 = 0; *(uint8_t*)0x2000a009 = 0; *(uint8_t*)0x2000a00a = 0; *(uint8_t*)0x2000a00b = 0; *(uint32_t*)0x2000a00c = 0; *(uint64_t*)0x2000a010 = 0; *(uint64_t*)0x2000a018 = 0; *(uint64_t*)0x2000a020 = 0; STORE_BY_BITMASK(uint64_t, 0x2000a028, 0, 0, 1); STORE_BY_BITMASK(uint64_t, 0x2000a028, 0, 1, 1); STORE_BY_BITMASK(uint64_t, 0x2000a028, 0, 2, 1); STORE_BY_BITMASK(uint64_t, 0x2000a028, 0, 3, 1); STORE_BY_BITMASK(uint64_t, 0x2000a028, 0, 4, 1); STORE_BY_BITMASK(uint64_t, 0x2000a028, 0, 5, 1); STORE_BY_BITMASK(uint64_t, 0x2000a028, 0, 6, 1); STORE_BY_BITMASK(uint64_t, 0x2000a028, 0, 7, 1); STORE_BY_BITMASK(uint64_t, 0x2000a028, 0, 8, 1); STORE_BY_BITMASK(uint64_t, 0x2000a028, 0, 9, 1); STORE_BY_BITMASK(uint64_t, 0x2000a028, 0, 10, 1); STORE_BY_BITMASK(uint64_t, 0x2000a028, 0, 11, 1); STORE_BY_BITMASK(uint64_t, 0x2000a028, 0, 12, 1); STORE_BY_BITMASK(uint64_t, 0x2000a028, 0, 13, 1); STORE_BY_BITMASK(uint64_t, 0x2000a028, 0, 14, 1); STORE_BY_BITMASK(uint64_t, 0x2000a028, 0, 15, 2); STORE_BY_BITMASK(uint64_t, 0x2000a028, 0, 17, 1); STORE_BY_BITMASK(uint64_t, 0x2000a028, 0, 18, 1); STORE_BY_BITMASK(uint64_t, 0x2000a028, 0, 19, 1); STORE_BY_BITMASK(uint64_t, 0x2000a028, 0, 20, 1); STORE_BY_BITMASK(uint64_t, 0x2000a028, 0, 21, 1); STORE_BY_BITMASK(uint64_t, 0x2000a028, 0, 22, 1); STORE_BY_BITMASK(uint64_t, 0x2000a028, 0, 23, 1); STORE_BY_BITMASK(uint64_t, 0x2000a028, 0, 24, 1); STORE_BY_BITMASK(uint64_t, 0x2000a028, 0, 25, 1); STORE_BY_BITMASK(uint64_t, 0x2000a028, 0, 26, 1); STORE_BY_BITMASK(uint64_t, 0x2000a028, 0, 27, 1); STORE_BY_BITMASK(uint64_t, 0x2000a028, 0, 28, 1); STORE_BY_BITMASK(uint64_t, 0x2000a028, 0, 29, 35); *(uint32_t*)0x2000a030 = 0; *(uint32_t*)0x2000a034 = 0; *(uint64_t*)0x2000a038 = 0x20000000; *(uint64_t*)0x2000a040 = 0; *(uint64_t*)0x2000a048 = 0; *(uint64_t*)0x2000a050 = 0; *(uint32_t*)0x2000a058 = 0; *(uint32_t*)0x2000a05c = 0; *(uint64_t*)0x2000a060 = 0; *(uint32_t*)0x2000a068 = 0; *(uint16_t*)0x2000a06c = 0; *(uint16_t*)0x2000a06e = 0; syscall(__NR_perf_event_open, 0x2000a000, 0, 0, -1, 0); break; case 4: *(uint64_t*)0x20000100 = 0x200000c0; *(uint64_t*)0x20000108 = 0x37; syscall(__NR_preadv, r[0], 0x20000100, 1, 0); break; case 5: memcpy((void*)0x20000200, "./file0", 8); syscall(__NR_umount2, 0x20000200, 0); break; } } void loop() { execute(6); } int main() { syscall(__NR_mmap, 0x20000000, 0x1000000, 3, 0x32, -1, 0); loop(); return 0; }