// https://syzkaller.appspot.com/bug?id=61c21a013edfca17cbd4ece3b3799967c56b5024 // 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 #ifndef SYS_compat_50_mknod #define SYS_compat_50_mknod 14 #endif #ifndef SYS_ioctl #define SYS_ioctl 54 #endif #ifndef SYS_mmap #define SYS_mmap 197 #endif #ifndef SYS_open #define SYS_open 5 #endif #ifndef SYS_openat #define SYS_openat 468 #endif static unsigned long long procid; static void kill_and_wait(int pid, int* status) { kill(pid, SIGKILL); while (waitpid(-1, status, 0) != pid) { } } 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 use_temporary_dir(void) { char tmpdir_template[] = "./syzkaller.XXXXXX"; char* tmpdir = mkdtemp(tmpdir_template); if (!tmpdir) exit(1); if (chmod(tmpdir, 0777)) exit(1); if (chdir(tmpdir)) exit(1); } static void __attribute__((noinline)) remove_dir(const char* dir) { DIR* dp = opendir(dir); if (dp == NULL) { if (errno == EACCES) { if (rmdir(dir)) exit(1); return; } exit(1); } struct dirent* ep = 0; while ((ep = readdir(dp))) { if (strcmp(ep->d_name, ".") == 0 || strcmp(ep->d_name, "..") == 0) continue; char filename[FILENAME_MAX]; snprintf(filename, sizeof(filename), "%s/%s", dir, ep->d_name); struct stat st; if (lstat(filename, &st)) exit(1); if (S_ISDIR(st.st_mode)) { remove_dir(filename); continue; } if (unlink(filename)) exit(1); } closedir(dp); if (rmdir(dir)) exit(1); } static void sandbox_common() { if (setsid() == -1) exit(1); struct rlimit 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); rlim.rlim_cur = rlim.rlim_max = 256; setrlimit(RLIMIT_NOFILE, &rlim); } static void loop(); static int do_sandbox_none(void) { sandbox_common(); loop(); return 0; } static void execute_one(void); #define WAIT_FLAGS 0 static void loop(void) { int iter = 0; for (;; iter++) { char cwdbuf[32]; sprintf(cwdbuf, "./%d", iter); if (mkdir(cwdbuf, 0777)) exit(1); int pid = fork(); if (pid < 0) exit(1); if (pid == 0) { if (chdir(cwdbuf)) exit(1); 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; } remove_dir(cwdbuf); } } uint64_t r[1] = {0xffffffffffffffff}; void execute_one(void) { intptr_t res = 0; memcpy((void*)0x20000000, "./file0\000", 8); syscall(SYS_compat_50_mknod, 0x20000000ul, 0x2000ul, 0x3000); memcpy((void*)0x20000280, "./file0\000", 8); syscall(SYS_openat, 0xffffff9c, 0x20000280ul, 0ul, 0x80ul); memcpy((void*)0x20000040, "./file0\000", 8); res = syscall(SYS_open, 0x20000040ul, 0x611ul, 0ul); if (res != -1) r[0] = res; *(uint32_t*)0x20000080 = 0; syscall(SYS_ioctl, r[0], 0x8004667cul, 0x20000080ul); } int main(void) { syscall(SYS_mmap, 0x20000000ul, 0x1000000ul, 3ul, 0x1012ul, -1, 0ul, 0ul); for (procid = 0; procid < 6; procid++) { if (fork() == 0) { use_temporary_dir(); do_sandbox_none(); } } sleep(1000000); return 0; }