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Date: Tue, 17 Dec 2024 12:30:36 -0800
From: Kees Cook <kees@kernel.org>
To: Willem de Bruijn <willemdebruijn.kernel@gmail.com>
Cc: "David S. Miller" <davem@davemloft.net>,
	Eric Dumazet <edumazet@google.com>,
	Jakub Kicinski <kuba@kernel.org>, Paolo Abeni <pabeni@redhat.com>,
	netdev@vger.kernel.org, Simon Horman <horms@kernel.org>,
	David Ahern <dsahern@kernel.org>,
	Sebastian Andrzej Siewior <bigeasy@linutronix.de>,
	Lorenzo Bianconi <lorenzo@kernel.org>,
	Joe Damato <jdamato@fastly.com>,
	Alexander Lobakin <aleksander.lobakin@intel.com>,
	linux-kernel@vger.kernel.org, linux-hardening@vger.kernel.org
Subject: Re: [PATCH] net: core: dev.c confirmed to use classic sockaddr
Message-ID: <202412171230.824B83D@keescook>
References: <20241217012445.work.979-kees@kernel.org>
 <67619a5029d2c_a046929426@willemb.c.googlers.com.notmuch>
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In-Reply-To: <67619a5029d2c_a046929426@willemb.c.googlers.com.notmuch>

On Tue, Dec 17, 2024 at 10:35:44AM -0500, Willem de Bruijn wrote:
> Kees Cook wrote:
> > As part of trying to clean up struct sock_addr, add comments about the
> > sockaddr arguments of dev_[gs]et_mac_address() being actual classic "max
> > 14 bytes in sa_data" sockaddr instances and not struct sockaddr_storage.
> 
> What is this assertion based on?
> 
> I see various non-Ethernet .ndo_set_mac_address implementations, which
> dev_set_mac_address calls. And dev_set_mac_addr_user is called from
> rtnetlink do_setlink. Which kmalloc's sa based on dev->addr_len.

Yeah, I was clearly missing several cases. Please ignore this patch. I
will re-examine this.

-- 
Kees Cook