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Date: Thu, 23 Oct 2025 09:33:20 -0700
From: Kees Cook <kees@kernel.org>
To: David Laight <david.laight.linux@gmail.com>
Cc: Jakub Kicinski <kuba@kernel.org>,
	"Gustavo A. R. Silva" <gustavo@embeddedor.com>,
	Alexei Starovoitov <ast@kernel.org>,
	Daniel Borkmann <daniel@iogearbox.net>,
	John Fastabend <john.fastabend@gmail.com>,
	"David S. Miller" <davem@davemloft.net>,
	Eric Dumazet <edumazet@google.com>, Paolo Abeni <pabeni@redhat.com>,
	Simon Horman <horms@kernel.org>,
	Kuniyuki Iwashima <kuniyu@google.com>,
	Willem de Bruijn <willemb@google.com>, netdev@vger.kernel.org,
	linux-kernel@vger.kernel.org, bpf@vger.kernel.org,
	linux-hardening@vger.kernel.org
Subject: Re: [PATCH v3 1/9] net: Add struct sockaddr_unspec for sockaddr of
 unknown length
Message-ID: <202510230932.25CE49FC8@keescook>
References: <20251020212125.make.115-kees@kernel.org>
 <20251020212639.1223484-1-kees@kernel.org>
 <20251021102600.2838d216@pumpkin>
 <202510211232.77A0F8A@keescook>
 <20251022102624.18d2c6f7@pumpkin>
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In-Reply-To: <20251022102624.18d2c6f7@pumpkin>

On Wed, Oct 22, 2025 at 10:26:24AM +0100, David Laight wrote:
> If you do add a #define, it can generate the size from that of the
> supplied address structure (and error things that are stupidly short).

I have more patches coming that consolidate all the open-coded casting
and size checking into a macro. So far, only a couple places weren't
doing the full checking.

-- 
Kees Cook