Re: [PATCH 0/2] bpf: Build with -Wcast-function-type

On Mon, Sep 27, 2021 at 11:27 AM Kees Cook [off-list ref] wrote:

Hi,

In order to keep ahead of cases in the kernel where Control Flow Integrity
(CFI) may trip over function call casts, enabling -Wcast-function-type
is helpful. To that end, replace BPF_CAST_CALL() as it triggers warnings
with this option and is now one of the last places in the kernel in need
of fixing.

Thanks,

-Kees

Kees Cook (2):
  bpf: Replace "want address" users of BPF_CAST_CALL with BPF_CALL_IMM
  bpf: Replace callers of BPF_CAST_CALL with proper function typedef

Both patches look good to me. For the series:

Acked-by: Andrii Nakryiko <andrii@kernel.org>

 include/linux/bpf.h    |  4 +++-
 include/linux/filter.h |  7 +++----
 kernel/bpf/arraymap.c  |  7 +++----
 kernel/bpf/hashtab.c   | 13 ++++++-------
 kernel/bpf/helpers.c   |  5 ++---
 kernel/bpf/verifier.c  | 26 +++++++++-----------------
 6 files changed, 26 insertions(+), 36 deletions(-)

--
2.30.2