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> unsigned int scaling; > + int ret; > > - if (cnt > 15) > - cnt = 15; > - > - if (copy_from_user(&buf, ubuf, cnt)) > - return -EFAULT; > - buf[cnt] = '\0'; > - > - if (kstrtouint(buf, 10, &scaling)) > - return -EINVAL; > + ret = kstrtouint_from_user(ubuf, cnt, 10, &scaling); > + if (ret < 0) > + return ret; This thing returns 0 on success, so I think you could better do: if (ret) return ret; With that, for the series: Suggested-by: Yury Norov Reviewed-by: Yury Norov Thanks, Yury > > if (scaling >= SCHED_TUNABLESCALING_END) > return -EINVAL; > -- > 2.36.1 >