On Wed, Apr 03, 2019 at 07:45:36AM +0300, Yury Norov wrote: > Currently we parse user data byte after byte which leads to > overcomplification of parsing algorithm. The only user of > bitmap_parselist_user() is not performance-critical, and so we > can copy user data to kernel buffer and simply call > bitmap_parselist(). This rework lets us unify and simplify > bitmap_parselist() and bitmap_parselist_user(), which is done > in the following patch.
> + buf = kmalloc(ulen + 1, GFP_KERNEL); > + if (!buf) > + return -ENOMEM; > + > + buf[ulen] = 0; > + > + ret = copy_from_user(buf, ubuf, ulen); > + if (ret) > + goto out; Why not memdup_user() ? -- With Best Regards, Andy Shevchenko
