// https://syzkaller.appspot.com/bug?id=f036811a07cb0aabc485b4e75d2307bc3d0e4b40 // autogenerated by syzkaller (https://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 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; } } static bool write_file(const char* file, const char* what, ...) { char buf[1024]; va_list args; va_start(args, what); vsnprintf(buf, sizeof(buf), what, args); va_end(args); buf[sizeof(buf) - 1] = 0; int len = strlen(buf); int fd = open(file, O_WRONLY | O_CLOEXEC); if (fd == -1) return false; if (write(fd, buf, len) != len) { int err = errno; close(fd); errno = err; return false; } close(fd); return true; } #define MAX_FDS 30 static void setup_common() { if (mount(0, "/sys/fs/fuse/connections", "fusectl", 0, 0)) { } } static void setup_binderfs() { if (mkdir("/dev/binderfs", 0777)) { } if (mount("binder", "/dev/binderfs", "binder", 0, NULL)) { } if (symlink("/dev/binderfs", "./binderfs")) { } } static void loop(); static void sandbox_common() { prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0); setsid(); struct rlimit rlim; rlim.rlim_cur = rlim.rlim_max = (200 << 20); setrlimit(RLIMIT_AS, &rlim); rlim.rlim_cur = rlim.rlim_max = 32 << 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); rlim.rlim_cur = rlim.rlim_max = 256; setrlimit(RLIMIT_NOFILE, &rlim); if (unshare(CLONE_NEWNS)) { } if (mount(NULL, "/", NULL, MS_REC | MS_PRIVATE, NULL)) { } if (unshare(CLONE_NEWIPC)) { } if (unshare(0x02000000)) { } if (unshare(CLONE_NEWUTS)) { } if (unshare(CLONE_SYSVSEM)) { } typedef struct { const char* name; const char* value; } sysctl_t; static const sysctl_t sysctls[] = { {"/proc/sys/kernel/shmmax", "16777216"}, {"/proc/sys/kernel/shmall", "536870912"}, {"/proc/sys/kernel/shmmni", "1024"}, {"/proc/sys/kernel/msgmax", "8192"}, {"/proc/sys/kernel/msgmni", "1024"}, {"/proc/sys/kernel/msgmnb", "1024"}, {"/proc/sys/kernel/sem", "1024 1048576 500 1024"}, }; unsigned i; for (i = 0; i < sizeof(sysctls) / sizeof(sysctls[0]); i++) write_file(sysctls[i].name, sysctls[i].value); } static int wait_for_loop(int pid) { if (pid < 0) exit(1); int status = 0; while (waitpid(-1, &status, __WALL) != pid) { } return WEXITSTATUS(status); } static void drop_caps(void) { struct __user_cap_header_struct cap_hdr = {}; struct __user_cap_data_struct cap_data[2] = {}; cap_hdr.version = _LINUX_CAPABILITY_VERSION_3; cap_hdr.pid = getpid(); if (syscall(SYS_capget, &cap_hdr, &cap_data)) exit(1); const int drop = (1 << CAP_SYS_PTRACE) | (1 << CAP_SYS_NICE); cap_data[0].effective &= ~drop; cap_data[0].permitted &= ~drop; cap_data[0].inheritable &= ~drop; if (syscall(SYS_capset, &cap_hdr, &cap_data)) exit(1); } static int do_sandbox_none(void) { if (unshare(CLONE_NEWPID)) { } int pid = fork(); if (pid != 0) return wait_for_loop(pid); setup_common(); sandbox_common(); drop_caps(); if (unshare(CLONE_NEWNET)) { } setup_binderfs(); loop(); exit(1); } static void kill_and_wait(int pid, int* status) { kill(-pid, SIGKILL); kill(pid, SIGKILL); for (int i = 0; i < 100; i++) { if (waitpid(-1, status, WNOHANG | __WALL) == pid) return; usleep(1000); } DIR* dir = opendir("/sys/fs/fuse/connections"); if (dir) { for (;;) { struct dirent* ent = readdir(dir); if (!ent) break; if (strcmp(ent->d_name, ".") == 0 || strcmp(ent->d_name, "..") == 0) continue; char abort[300]; snprintf(abort, sizeof(abort), "/sys/fs/fuse/connections/%s/abort", ent->d_name); int fd = open(abort, O_WRONLY); if (fd == -1) { continue; } if (write(fd, abort, 1) < 0) { } close(fd); } closedir(dir); } else { } while (waitpid(-1, status, __WALL) != pid) { } } static void setup_test() { prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0); setpgrp(); write_file("/proc/self/oom_score_adj", "1000"); } static void close_fds() { for (int fd = 3; fd < MAX_FDS; fd++) close(fd); } 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 execute_one(void) { int i, call, thread; for (call = 0; call < 10; 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); close_fds(); } static void execute_one(void); #define WAIT_FLAGS __WALL static void loop(void) { int iter = 0; for (;; iter++) { int pid = fork(); if (pid < 0) exit(1); if (pid == 0) { setup_test(); execute_one(); exit(0); } int status = 0; uint64_t start = current_time_ms(); for (;;) { if (waitpid(-1, &status, WNOHANG | WAIT_FLAGS) == pid) break; sleep_ms(1); if (current_time_ms() - start < 5000) continue; kill_and_wait(pid, &status); break; } } } uint64_t r[4] = {0xffffffffffffffff, 0xffffffffffffffff, 0xffffffffffffffff, 0xffffffffffffffff}; void execute_call(int call) { intptr_t res = 0; switch (call) { case 0: memcpy((void*)0x20000080, "./file0\000", 8); syscall(__NR_mkdir, 0x20000080ul, 0ul); break; case 1: res = syscall(__NR_pipe2, 0x20000240ul, 0ul); if (res != -1) { r[0] = *(uint32_t*)0x20000240; r[1] = *(uint32_t*)0x20000244; } break; case 2: syscall(__NR_close, r[0]); break; case 3: syscall(__NR_socket, 0x10ul, 3ul, 6); break; case 4: memcpy((void*)0x20000200, "/sys/kernel/debug/binder/failed_transaction_log\000", 48); res = syscall(__NR_openat, 0xffffffffffffff9cul, 0x20000200ul, 0ul, 0ul); if (res != -1) r[2] = res; break; case 5: memcpy((void*)0x20000180, "./file0\000", 8); memcpy((void*)0x200001c0, "9p\000", 3); memcpy((void*)0x20000280, "trans=fd,", 9); memcpy((void*)0x20000289, "rfdno", 5); *(uint8_t*)0x2000028e = 0x3d; sprintf((char*)0x2000028f, "0x%016llx", (long long)r[2]); *(uint8_t*)0x200002a1 = 0x2c; memcpy((void*)0x200002a2, "wfdno", 5); *(uint8_t*)0x200002a7 = 0x3d; sprintf((char*)0x200002a8, "0x%016llx", (long long)r[0]); *(uint8_t*)0x200002ba = 0x2c; memcpy((void*)0x200002bb, "fscache", 7); *(uint8_t*)0x200002c2 = 0x2c; memcpy((void*)0x200002c3, "dfltgid", 7); *(uint8_t*)0x200002ca = 0x3d; sprintf((char*)0x200002cb, "0x%016llx", (long long)0xee00); *(uint8_t*)0x200002dd = 0x2c; memcpy((void*)0x200002de, "access=user", 11); *(uint8_t*)0x200002e9 = 0x2c; memcpy((void*)0x200002ea, "access=client", 13); *(uint8_t*)0x200002f7 = 0x2c; memcpy((void*)0x200002f8, "hash", 4); *(uint8_t*)0x200002fc = 0x2c; memcpy((void*)0x200002fd, "fsuuid", 6); *(uint8_t*)0x20000303 = 0x3d; *(uint8_t*)0x20000304 = 0x61; *(uint8_t*)0x20000305 = 0x33; *(uint8_t*)0x20000306 = 0x39; *(uint8_t*)0x20000307 = 0x36; *(uint8_t*)0x20000308 = 0x62; *(uint8_t*)0x20000309 = 0x32; *(uint8_t*)0x2000030a = 0x65; *(uint8_t*)0x2000030b = 0x37; *(uint8_t*)0x2000030c = 0x2d; *(uint8_t*)0x2000030d = 0x65; *(uint8_t*)0x2000030e = 0x33; *(uint8_t*)0x2000030f = 0x33; *(uint8_t*)0x20000310 = 0x30; *(uint8_t*)0x20000311 = 0x2d; *(uint8_t*)0x20000312 = 0x62; *(uint8_t*)0x20000313 = 0x63; *(uint8_t*)0x20000314 = 0x34; *(uint8_t*)0x20000315 = 0x61; *(uint8_t*)0x20000316 = 0x2d; *(uint8_t*)0x20000317 = 0x38; *(uint8_t*)0x20000318 = 0x39; *(uint8_t*)0x20000319 = 0x33; *(uint8_t*)0x2000031a = 0x31; *(uint8_t*)0x2000031b = 0x2d; *(uint8_t*)0x2000031c = 0x63; *(uint8_t*)0x2000031d = 0x65; *(uint8_t*)0x2000031e = 0x63; *(uint8_t*)0x2000031f = 0x32; *(uint8_t*)0x20000320 = 0x34; *(uint8_t*)0x20000321 = 0x34; *(uint8_t*)0x20000322 = 0x31; *(uint8_t*)0x20000323 = 0x32; *(uint8_t*)0x20000324 = 0x2c; memcpy((void*)0x20000325, "appraise", 8); *(uint8_t*)0x2000032d = 0x2c; memcpy((void*)0x2000032e, "fowner>", 7); sprintf((char*)0x20000335, "%020llu", (long long)0); *(uint8_t*)0x20000349 = 0x2c; memcpy((void*)0x2000034a, "fsuuid", 6); *(uint8_t*)0x20000350 = 0x3d; *(uint8_t*)0x20000351 = 0x61; *(uint8_t*)0x20000352 = 0x32; *(uint8_t*)0x20000353 = 0x35; *(uint8_t*)0x20000354 = 0x65; *(uint8_t*)0x20000355 = 0x31; *(uint8_t*)0x20000356 = 0x61; *(uint8_t*)0x20000357 = 0x66; *(uint8_t*)0x20000358 = 0x34; *(uint8_t*)0x20000359 = 0x2d; *(uint8_t*)0x2000035a = 0x42; *(uint8_t*)0x2000035b = 0x31; *(uint8_t*)0x2000035c = 0x31; *(uint8_t*)0x2000035d = 0x38; *(uint8_t*)0x2000035e = 0x2d; *(uint8_t*)0x2000035f = 0x66; *(uint8_t*)0x20000360 = 0x61; *(uint8_t*)0x20000361 = 0x62; *(uint8_t*)0x20000362 = 0x33; *(uint8_t*)0x20000363 = 0x2d; *(uint8_t*)0x20000364 = 0x61; *(uint8_t*)0x20000365 = 0x37; *(uint8_t*)0x20000366 = 0x34; *(uint8_t*)0x20000367 = 0x63; *(uint8_t*)0x20000368 = 0x2d; *(uint8_t*)0x20000369 = 0x32; *(uint8_t*)0x2000036a = 0x66; *(uint8_t*)0x2000036b = 0x61; *(uint8_t*)0x2000036c = 0x32; *(uint8_t*)0x2000036d = 0x34; *(uint8_t*)0x2000036e = 0x37; *(uint8_t*)0x2000036f = 0x32; *(uint8_t*)0x20000370 = 0x33; *(uint8_t*)0x20000371 = 0x2c; memcpy((void*)0x20000372, "fsuuid", 6); *(uint8_t*)0x20000378 = 0x3d; *(uint8_t*)0x20000379 = 0x65; *(uint8_t*)0x2000037a = 0x66; *(uint8_t*)0x2000037b = 0x30; *(uint8_t*)0x2000037c = 0x36; *(uint8_t*)0x2000037d = 0x33; *(uint8_t*)0x2000037e = 0x36; *(uint8_t*)0x2000037f = 0x38; *(uint8_t*)0x20000380 = 0x61; *(uint8_t*)0x20000381 = 0x2d; *(uint8_t*)0x20000382 = 0x61; *(uint8_t*)0x20000383 = 0x61; *(uint8_t*)0x20000384 = 0x64; *(uint8_t*)0x20000385 = 0x30; *(uint8_t*)0x20000386 = 0x2d; *(uint8_t*)0x20000387 = 0x66; *(uint8_t*)0x20000388 = 0x35; *(uint8_t*)0x20000389 = 0x66; *(uint8_t*)0x2000038a = 0x39; *(uint8_t*)0x2000038b = 0x2d; *(uint8_t*)0x2000038c = 0x61; *(uint8_t*)0x2000038d = 0x39; *(uint8_t*)0x2000038e = 0x34; *(uint8_t*)0x2000038f = 0x30; *(uint8_t*)0x20000390 = 0x2d; *(uint8_t*)0x20000391 = 0x33; *(uint8_t*)0x20000392 = 0x64; *(uint8_t*)0x20000393 = 0x30; *(uint8_t*)0x20000394 = 0x64; *(uint8_t*)0x20000395 = 0x38; *(uint8_t*)0x20000396 = 0x37; *(uint8_t*)0x20000397 = 0x65; *(uint8_t*)0x20000398 = 0x34; *(uint8_t*)0x20000399 = 0x2c; *(uint8_t*)0x2000039a = 0; syscall(__NR_mount, 0ul, 0x20000180ul, 0x200001c0ul, 0x10ul, 0x20000280ul); break; case 6: res = syscall(__NR_epoll_create1, 0ul); if (res != -1) r[3] = res; break; case 7: memcpy((void*)0x20000040, "./file0\000", 8); memcpy((void*)0x200000c0, "9p\000", 3); memcpy((void*)0x20000b40, "trans=fd,", 9); memcpy((void*)0x20000b49, "rfdno", 5); *(uint8_t*)0x20000b4e = 0x3d; sprintf((char*)0x20000b4f, "0x%016llx", (long long)r[0]); *(uint8_t*)0x20000b61 = 0x2c; memcpy((void*)0x20000b62, "wfdno", 5); *(uint8_t*)0x20000b67 = 0x3d; sprintf((char*)0x20000b68, "0x%016llx", (long long)r[3]); *(uint8_t*)0x20000b7a = 0x2c; *(uint8_t*)0x20000b7b = 0x6b; syscall(__NR_mount, 0ul, 0x20000040ul, 0x200000c0ul, 0ul, 0x20000b40ul); break; case 8: *(uint32_t*)0x20000000 = 0; *(uint64_t*)0x20000004 = 0; syscall(__NR_epoll_ctl, r[3], 1ul, r[1], 0x20000000ul); break; case 9: memcpy((void*)0x20000040, "./file0\000", 8); memcpy((void*)0x200000c0, "9p\000", 3); memcpy((void*)0x20000b40, "trans=fd,", 9); memcpy((void*)0x20000b49, "rfdno", 5); *(uint8_t*)0x20000b4e = 0x3d; sprintf((char*)0x20000b4f, "0x%016llx", (long long)r[0]); *(uint8_t*)0x20000b61 = 0x2c; memcpy((void*)0x20000b62, "wfdno", 5); *(uint8_t*)0x20000b67 = 0x3d; sprintf((char*)0x20000b68, "0x%016llx", (long long)r[3]); *(uint8_t*)0x20000b7a = 0x2c; *(uint8_t*)0x20000b7b = 0x6b; syscall(__NR_mount, 0ul, 0x20000040ul, 0x200000c0ul, 0ul, 0x20000b40ul); break; } } int main(void) { syscall(__NR_mmap, 0x1ffff000ul, 0x1000ul, 0ul, 0x32ul, -1, 0ul); syscall(__NR_mmap, 0x20000000ul, 0x1000000ul, 7ul, 0x32ul, -1, 0ul); syscall(__NR_mmap, 0x21000000ul, 0x1000ul, 0ul, 0x32ul, -1, 0ul); do_sandbox_none(); return 0; }