Subject: Re: [PATCH v2 5/6] bna: Avoid clashing function prototypes

From: "Gustavo A. R. Silva" <[email-masked]>
Date: Mon, 31 Oct 2022 16:04:57 -0500

On Sat, Oct 29, 2022 at 12:12:26AM -0700, Kees Cook wrote:
> On Thu, Oct 27, 2022 at 03:20:47PM -0500, Gustavo A. R. Silva wrote:
> > When built with Control Flow Integrity, function prototypes between
> > caller and function declaration must match. These mismatches are visible
> > at compile time with the new -Wcast-function-type-strict in Clang[1].
> > 
> > Fix a total of 227 warnings like these:
> > 
> > drivers/net/ethernet/brocade/bna/bna_enet.c:519:3: warning: cast from 'void (*)(struct bna_ethport *, enum bna_ethport_event)' to 'bfa_fsm_t' (aka 'void (*)(void *, int)') converts to incompatible function type [-Wcast-function-type-strict]
> >                 bfa_fsm_set_state(ethport, bna_ethport_sm_down);
> >                 ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> > 
> > The bna state machine code heavily overloads its state machine functions,
> > so these have been separated into their own sets of structs, enums,
> > typedefs, and helper functions. There are almost zero binary code changes,
> > all seem to be related to header file line numbers changing, or the
> > addition of the new stats helper.
> 
> This looks like it borrowed from
> https://lore.kernel.org/linux-hardening/[email-masked]/
> Nice to get a couple hundred more fixed. :)

Yep; you're right. That's exactly the patch I was staring at
while doing these changes. :)

> 
> > [1] https://reviews.llvm.org/D134831
> > Signed-off-by: Gustavo A. R. Silva <[email-masked]>
> > ---
> > Changes in v2:
> >  - None. This patch is new in the series.
> 
> This is relatively stand-alone (not an iw_handler patch), so it could
> also go separately too.

My criteria here was that all these patches avoid clashing function
prototypes. So, they could be put together into a series, regardless
if they are "iw_handler" related patches.

> Reviewed-by: Kees Cook <[email-masked]>

Thanks!
--
Gustavo