/* * find out whether an object in the current working directory is in use or not * - command: "inuse <name>" */ static int cachefiles_daemon_inuse(struct cachefiles_cache *cache, char *args) { struct path path; const struct cred *saved_cred; int ret; //_enter(",%s", args); if (strchr(args, '/')) goto inval; if (!test_bit(CACHEFILES_READY, &cache->flags)) { pr_err("inuse applied to unready cache\n"); return -EIO; } if (test_bit(CACHEFILES_DEAD, &cache->flags)) { pr_err("inuse applied to dead cache\n"); return -EIO; } /* extract the directory dentry from the cwd */ get_fs_pwd(current->fs, &path); if (!d_can_lookup(path.dentry)) goto notdir; cachefiles_begin_secure(cache, &saved_cred); ret = cachefiles_check_in_use(cache, path.dentry, args); cachefiles_end_secure(cache, saved_cred); path_put(&path); //_leave(" = %d", ret); return ret; notdir: path_put(&path); pr_err("inuse command requires dirfd to be a directory\n"); return -ENOTDIR; inval: pr_err("inuse command requires dirfd and filename\n"); return -EINVAL; }
SYSCALL_DEFINE1(fchdir, unsigned int, fd) { struct fd f = fdget_raw(fd); int error; error = -EBADF; if (!f.file) goto out; error = -ENOTDIR; if (!d_can_lookup(f.file->f_path.dentry)) goto out_putf; error = inode_permission(file_inode(f.file), MAY_EXEC | MAY_CHDIR); if (!error) set_fs_pwd(current->fs, &f.file->f_path); out_putf: fdput(f); out: return error; }