Re: [PATCH] rtnetlink: fix uninitialized variable

From: Jakub Kicinski
Date: Tue Jul 17 2018 - 13:57:33 EST


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@xxxxxxxxxxxxxx>

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