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Date: Thu, 11 Nov 2021 09:54:44 -0800
From: Jakub Kicinski <kuba@kernel.org>
To: Tadeusz Struk <tadeusz.struk@linaro.org>, "David S. Miller"
 <davem@davemloft.net>
Cc: Marco Elver <elver@google.com>, Nathan Chancellor <nathan@kernel.org>,
 Nick Desaulniers <ndesaulniers@google.com>, Jonathan Lemon
 <jonathan.lemon@gmail.com>, Alexander Lobakin <alobakin@pm.me>, Willem de
 Bruijn <willemb@google.com>, Paolo Abeni <pabeni@redhat.com>, Cong Wang
 <cong.wang@bytedance.com>, Kevin Hao <haokexin@gmail.com>, Ilias Apalodimas
 <ilias.apalodimas@linaro.org>, netdev@vger.kernel.org,
 linux-kernel@vger.kernel.org, llvm@lists.linux.dev, Kees Cook
 <keescook@chromium.org>, Eric Dumazet <edumazet@google.com>
Subject: Re: [PATCH] skbuff: suppress clang object-size-mismatch error
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On Thu, 11 Nov 2021 08:01:26 -0800 Tadeusz Struk wrote:
> > That general advice might not be compatible with what the kernel
> > wants, especially since UBSAN_OBJECT_SIZE is normally disabled and I
> > think known to cause these issues in the kernel.
> > 
> > I'll defer to maintainers to decide what would be the preferred way of
> > handling this.  
> 
> Sure, I would also like to know if there is a better way of fixing this.
> Thanks for your feedback.

I remember Dave was working thru the tree at some point to clean up all
skb->next/skb->prev accesses so that we can switch over to using normal
list helpers.

I'm not sure if that stalled due to lack of time or some fundamental
problems.

Seems like finishing that would let us clean up such misuses?