Date:   Tue, 14 Mar 2023 01:04:04 +0200
From:   Vladimir Oltean <olteanv@gmail.com>
To:     Simon Horman <simon.horman@corigine.com>
Cc:     Danila Chernetsov <listdansp@mail.ru>,
        Andrew Lunn <andrew@lunn.ch>,
        Florian Fainelli <f.fainelli@gmail.com>,
        "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,
        linux-kernel@vger.kernel.org, lvc-project@linuxtesting.org
Subject: Re: [PATCH] net: dsa: vsc73xxx: Fix uninitalized 'val' in
 vsc73xx_adjust_link
Message-ID: <20230313230404.vww27tkxh6xvp24h@skbuf>
References: <20230312155008.7830-1-listdansp@mail.ru>
 <ZA9yj1FT7eLOCU34@corigine.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <ZA9yj1FT7eLOCU34@corigine.com>
Precedence: bulk

On Mon, Mar 13, 2023 at 07:59:27PM +0100, Simon Horman wrote:
> On Sun, Mar 12, 2023 at 03:50:08PM +0000, Danila Chernetsov wrote:
> > Using uninitialized variable after calls vsc73xx_read 
> > without error checking may cause incorrect driver behavior.
> 
> I wonder if it is:
> a) intentional that these calls are not checked for errors

probably no; this is precisely the only vsc73xx_read() call whose return
code is ignores. I'd say it partly has to do with the fact that vsc73xx_adjust_link()
returns void, so the author was thinking there'd be no point in checking
for errors, but there clearly is

> b) errors can occur in these call paths

probably yes; one of the instantiations of vsc73xx is over SPI, where
the controller can time out, etc.