On Sun, Jul 26, 2020 at 06:04:01PM +0200, Christoph Hellwig wrote: > Fold the misaligned u64 workarounds into the main quotactl flow instead > of implementing a separate compat syscall handler. I can live with that (and drop the local quota-related stuff from copy_in_user/compat_alloc_user_space elimination series). One question, though: > +static int compat_copy_fs_qfilestat(struct compat_fs_qfilestat __user *to, > + struct fs_qfilestat *from) > +{ > + if (copy_to_user(to, from, sizeof(*to)) || > + put_user(from->qfs_nextents, &to->qfs_nextents)) > + return -EFAULT; > + return 0; > +} do we have any need of that put_user()? Note that you don't even call that thing unless compat_need_64bit_alignment_fixup() is true. And AFAICS all such cases are little-endian...