Merge patch series "uaccess/sockptr: copy_struct_ fixes and more helpers"

Stefan Metzmacher <metze@samba.org> says:

Here are some patches related to
copy_struct_{from,to}_{user,sockptr}()
I collected during my work on an IPPROTO_SMBDIRECT
implementation wrapping the smbdirect code used
by cifs.ko and ksmbd.ko.

The first patch fixes copy_struct_to_user()
to behave like documented.

The 2nd patch fixes the case where
copy_struct_from_user() is called by
copy_struct_from_sockptr().

The 3rd patch introduces
copy_struct_{from,to}_bounce_buffer()
as a result of a discussion about the
IPPROTO_QUIC driver in order to
be future prove when handling msg_control
messages in sendmsg and recvmsg.
But I'll likely also use them in my
IPPROTO_SMBDIRECT driver.

The 4th patch makes copy_struct_from_sockptr()
a trivial wrapper switching between
copy_struct_from_user() and
copy_struct_from_bounce_buffer()

The 5th patch introduces copy_struct_to_sockptr()
which I'll also use in my IPPROTO_SMBDIRECT driver.

* patches from https://patch.msgid.link/cover.1775576651.git.metze@samba.org:
  sockptr: introduce copy_struct_to_sockptr()
  sockptr: let copy_struct_from_sockptr() use copy_struct_from_bounce_buffer()
  uaccess: add copy_struct_{from,to}_bounce_buffer() helpers
  sockptr: fix usize check in copy_struct_from_sockptr() for user pointers
  uaccess: fix ignored_trailing logic in copy_struct_to_user()

Link: https://patch.msgid.link/cover.1775576651.git.metze@samba.org
Signed-off-by: Christian Brauner <brauner@kernel.org>