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Date: Tue, 5 Nov 2024 17:16:07 -0800
From: Jakub Kicinski <kuba@kernel.org>
To: Kees Cook <kees@kernel.org>
Cc: "Gustavo A. R. Silva" <gustavoars@kernel.org>,
 linux-kernel@vger.kernel.org, netdev@vger.kernel.org,
 linux-hardening@vger.kernel.org
Subject: Re: [PATCH RFC 0/5] sockaddr usage removal
Message-ID: <20241105171607.48c0c24d@kernel.org>
In-Reply-To: <20241104221450.work.053-kees@kernel.org>
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On Mon,  4 Nov 2024 14:25:02 -0800 Kees Cook wrote:
> I think for getname() (and similar interfaces) we *do* want to use
> sockaddr_storage, but there is kind of an argument to instead use
> a struct with a flexible array, e.g.:
> 
> struct sockaddr_unspec {
>         sa_family_t	sa_family;
> 	char		sa_data[];
> };
> 
> If this was done, then all these APIs would switch their casts from
> "(struct sockaddr *)" to "(struct sockaddr_unspec *)", even though in
> most cases the object is actully a struct sockaddr_storage.

struct sockaddr_unspec was my knee-jerk reaction but looking at the code
- indeed passing struct sockaddr_storage seems cleaner.

> What do folks think?

Looks nice, and feels like the right direction :)

FWIW if the conversion work is too tedious I think I can find some
people that could help.