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Date:   Tue, 17 Jul 2018 10:57:25 -0700
From:   Jakub Kicinski <jakub.kicinski@netronome.com>
To:     "Gustavo A. R. Silva" <gustavo@embeddedor.com>
Cc:     "David S. Miller" <davem@davemloft.net>, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] rtnetlink: fix uninitialized variable
Message-ID: <20180717105725.5cb8a405@cakuba.lan>
In-Reply-To: <20180717134314.GA31127@embeddedor.com>
References: <20180717134314.GA31127@embeddedor.com>
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On Tue, 17 Jul 2018 08:43:14 -0500, Gustavo A. R. Silva wrote:
> Currently, there are execution paths in which variable err is
> returned without being properly initialized previously:
> 
> 1417        if (rtnl_xdp_report_one(skb, dev, &prog_id, &mode, XDP_ATTACHED_SKB,
> 1418                                IFLA_XDP_SKB_PROG_ID, rtnl_xdp_prog_skb))
> 1419                goto err_cancel;
> 1420        if (rtnl_xdp_report_one(skb, dev, &prog_id, &mode, XDP_ATTACHED_DRV,
> 1421                                IFLA_XDP_DRV_PROG_ID, rtnl_xdp_prog_drv))
> 1422                goto err_cancel;
> 1423        if (rtnl_xdp_report_one(skb, dev, &prog_id, &mode, XDP_ATTACHED_HW,
> 1424                                IFLA_XDP_HW_PROG_ID, rtnl_xdp_prog_hw))
> 1425                goto err_cancel;
> 
> Fix this by initializing variable err to -EMSGSIZE.
> 
> Addresses-Coverity-ID: 1471831 ("Uninitialized scalar variable")
> Fixes: a25717d2b604 ("xdp: support simultaneous driver and hw XDP attachment")
> Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>

Looks like duplicate of:

http://patchwork.ozlabs.org/patch/944662/

Strage GCC doesn't catch this even with W=1, the code is fairly
straightforward :S