// https://syzkaller.appspot.com/bug?id=b2e1556716a64f70e53256feb878d22a288f483e // autogenerated by syzkaller (https://github.com/google/syzkaller) #define _GNU_SOURCE #include #include #include #include #include #include #include #include #include #include #include #include static void sleep_ms(uint64_t ms) { usleep(ms * 1000); } static uint64_t current_time_ms(void) { struct timespec ts; if (clock_gettime(CLOCK_MONOTONIC, &ts)) exit(1); return (uint64_t)ts.tv_sec * 1000 + (uint64_t)ts.tv_nsec / 1000000; } static void thread_start(void* (*fn)(void*), void* arg) { pthread_t th; pthread_attr_t attr; pthread_attr_init(&attr); pthread_attr_setstacksize(&attr, 128 << 10); int i = 0; for (; i < 100; i++) { if (pthread_create(&th, &attr, fn, arg) == 0) { pthread_attr_destroy(&attr); return; } if (errno == EAGAIN) { usleep(50); continue; } break; } exit(1); } typedef struct { int state; } event_t; static void event_init(event_t* ev) { ev->state = 0; } static void event_reset(event_t* ev) { ev->state = 0; } static void event_set(event_t* ev) { if (ev->state) exit(1); __atomic_store_n(&ev->state, 1, __ATOMIC_RELEASE); syscall(SYS_futex, &ev->state, FUTEX_WAKE | FUTEX_PRIVATE_FLAG, 1000000); } static void event_wait(event_t* ev) { while (!__atomic_load_n(&ev->state, __ATOMIC_ACQUIRE)) syscall(SYS_futex, &ev->state, FUTEX_WAIT | FUTEX_PRIVATE_FLAG, 0, 0); } static int event_isset(event_t* ev) { return __atomic_load_n(&ev->state, __ATOMIC_ACQUIRE); } static int event_timedwait(event_t* ev, uint64_t timeout) { uint64_t start = current_time_ms(); uint64_t now = start; for (;;) { uint64_t remain = timeout - (now - start); struct timespec ts; ts.tv_sec = remain / 1000; ts.tv_nsec = (remain % 1000) * 1000 * 1000; syscall(SYS_futex, &ev->state, FUTEX_WAIT | FUTEX_PRIVATE_FLAG, 0, &ts); if (__atomic_load_n(&ev->state, __ATOMIC_ACQUIRE)) return 1; now = current_time_ms(); if (now - start > timeout) return 0; } } struct thread_t { int created, call; event_t ready, done; }; 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 (;;) { event_wait(&th->ready); event_reset(&th->ready); execute_call(th->call); __atomic_fetch_sub(&running, 1, __ATOMIC_RELAXED); event_set(&th->done); } return 0; } static void loop(void) { int i, call, thread; for (call = 0; call < 8; call++) { for (thread = 0; thread < (int)(sizeof(threads) / sizeof(threads[0])); thread++) { struct thread_t* th = &threads[thread]; if (!th->created) { th->created = 1; event_init(&th->ready); event_init(&th->done); event_set(&th->done); thread_start(thr, th); } if (!event_isset(&th->done)) continue; event_reset(&th->done); th->call = call; __atomic_fetch_add(&running, 1, __ATOMIC_RELAXED); event_set(&th->ready); event_timedwait(&th->done, 50); break; } } for (i = 0; i < 100 && __atomic_load_n(&running, __ATOMIC_RELAXED); i++) sleep_ms(1); } uint64_t r[3] = {0xffffffffffffffff, 0x0, 0x0}; void execute_call(int call) { intptr_t res = 0; switch (call) { case 0: memcpy((void*)0x20000400, "./file0\000", 8); syscall(__NR_mkdir, /*path=*/0x20000400ul, /*mode=*/0ul); break; case 1: memcpy((void*)0x20000040, "/dev/fuse\000", 10); res = syscall(__NR_openat, /*fd=*/0xffffffffffffff9cul, /*file=*/0x20000040ul, /*flags=*/0x42ul, /*mode=*/0ul); if (res != -1) r[0] = res; break; case 2: memcpy((void*)0x20000000, "./file0\000", 8); memcpy((void*)0x20002100, "fuse\000", 5); memcpy((void*)0x20002140, "fd=", 3); sprintf((char*)0x20002143, "0x%016llx", (long long)r[0]); memcpy((void*)0x20002155, ",rootmode=0000000000000000040000,user_id=", 41); sprintf((char*)0x2000217e, "%020llu", (long long)0); memcpy((void*)0x20002192, ",group_id=", 10); sprintf((char*)0x2000219c, "%020llu", (long long)0); syscall(__NR_mount, /*src=*/0ul, /*dst=*/0x20000000ul, /*type=*/0x20002100ul, /*flags=*/0ul, /*opts=*/0x20002140ul); break; case 3: res = syscall(__NR_read, /*fd=*/r[0], /*buf=*/0x200021c0ul, /*len=*/0x2020ul); if (res != -1) r[1] = *(uint64_t*)0x200021c8; break; case 4: memcpy((void*)0x20000200, "./file0/../file0/file0/file0\000", 29); syscall(__NR_mount, /*src=*/0ul, /*dst=*/0x20000200ul, /*type=*/0ul, /*flags=*/0ul, /*opts=*/0ul); break; case 5: *(uint32_t*)0x20004200 = 0x50; *(uint32_t*)0x20004204 = 0; *(uint64_t*)0x20004208 = r[1]; *(uint32_t*)0x20004210 = 7; *(uint32_t*)0x20004214 = 0x27; *(uint32_t*)0x20004218 = 0; *(uint32_t*)0x2000421c = 0; *(uint16_t*)0x20004220 = 0; *(uint16_t*)0x20004222 = 0; *(uint32_t*)0x20004224 = 0; *(uint32_t*)0x20004228 = 0; *(uint16_t*)0x2000422c = 0; *(uint16_t*)0x2000422e = 0; memset((void*)0x20004230, 0, 32); syscall(__NR_write, /*fd=*/r[0], /*arg=*/0x20004200ul, /*len=*/0x50ul); break; case 6: res = syscall(__NR_read, /*fd=*/r[0], /*buf=*/0x2000a280ul, /*len=*/0x2020ul); if (res != -1) r[2] = *(uint64_t*)0x2000a288; break; case 7: *(uint32_t*)0x20000240 = 0xa0; *(uint32_t*)0x20000244 = 0; *(uint64_t*)0x20000248 = r[2]; *(uint64_t*)0x20000250 = 2; *(uint64_t*)0x20000258 = 3; *(uint64_t*)0x20000260 = 1; *(uint64_t*)0x20000268 = 7; *(uint32_t*)0x20000270 = 8; *(uint32_t*)0x20000274 = 3; *(uint64_t*)0x20000278 = 6; *(uint64_t*)0x20000280 = 0x138; *(uint64_t*)0x20000288 = 6; *(uint64_t*)0x20000290 = 0xffffffff; *(uint64_t*)0x20000298 = 1; *(uint64_t*)0x200002a0 = 0xfff; *(uint32_t*)0x200002a8 = 0xfa; *(uint32_t*)0x200002ac = 0xffff0a82; *(uint32_t*)0x200002b0 = 0x101; *(uint32_t*)0x200002b4 = 0x8000; *(uint32_t*)0x200002b8 = 0x6e; *(uint32_t*)0x200002bc = 0; *(uint32_t*)0x200002c0 = 0; *(uint32_t*)0x200002c4 = 0x80000000; *(uint32_t*)0x200002c8 = 0x401; *(uint32_t*)0x200002cc = 0; *(uint64_t*)0x200002d0 = 0; *(uint32_t*)0x200002d8 = 0x10; *(uint32_t*)0x200002dc = 0; syscall(__NR_write, /*fd=*/r[0], /*arg=*/0x20000240ul, /*len=*/0xa0ul); break; } } int main(void) { syscall(__NR_mmap, /*addr=*/0x1ffff000ul, /*len=*/0x1000ul, /*prot=*/0ul, /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul, /*fd=*/-1, /*offset=*/0ul); syscall(__NR_mmap, /*addr=*/0x20000000ul, /*len=*/0x1000000ul, /*prot=PROT_WRITE|PROT_READ|PROT_EXEC*/ 7ul, /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul, /*fd=*/-1, /*offset=*/0ul); syscall(__NR_mmap, /*addr=*/0x21000000ul, /*len=*/0x1000ul, /*prot=*/0ul, /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul, /*fd=*/-1, /*offset=*/0ul); loop(); return 0; }