[PATCH] rtnetlink: fix uninitialized variable

From: Gustavo A. R. Silva
Date: Tue Jul 17 2018 - 09:43:45 EST


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>
---
net/core/rtnetlink.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index e03258e..648c984 100644
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -1405,12 +1405,12 @@ static int rtnl_xdp_fill(struct sk_buff *skb, struct net_device *dev)
{
struct nlattr *xdp;
u32 prog_id;
- int err;
+ int err = -EMSGSIZE;
u8 mode;

xdp = nla_nest_start(skb, IFLA_XDP);
if (!xdp)
- return -EMSGSIZE;
+ return err;

prog_id = 0;
mode = XDP_ATTACHED_NONE;
--
2.7.4