From: Arnd Bergmann <arnd@arndb.de>
To: "David S. Miller" <davem@davemloft.net>
Cc: Arnd Bergmann <arnd@arndb.de>,
Roopa Prabhu <roopa@cumulusnetworks.com>,
Nicolas Dichtel <nicolas.dichtel@6wind.com>,
Nikolay Aleksandrov <nikolay@cumulusnetworks.com>,
Jiri Pirko <jiri@mellanox.com>,
Eric Dumazet <edumazet@google.com>,
Brenden Blanco <bblanco@plumgrid.com>,
Hannes Frederic Sowa <hannes@stressinduktion.org>,
Nogah Frankel <nogahf@mellanox.com>,
netdev@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: [PATCH] net: rtnl: avoid uninitialized data in IFLA_VF_VLAN_LIST handling
Date: Fri, 30 Sep 2016 18:13:49 +0200 [thread overview]
Message-ID: <20160930161416.18660-1-arnd@arndb.de> (raw)
With the newly added support for IFLA_VF_VLAN_LIST netlink messages,
we get a warning about potential uninitialized variable use in
the parsing of the user input when enabling the -Wmaybe-uninitialized
warning:
net/core/rtnetlink.c: In function 'do_setvfinfo':
net/core/rtnetlink.c:1756:9: error: 'ivvl$' may be used uninitialized in this function [-Werror=maybe-uninitialized]
I have not been able to prove whether it is possible to arrive in
this code with an empty IFLA_VF_VLAN_LIST block, but if we do,
then ndo_set_vf_vlan gets called with uninitialized arguments.
This adds an explicit check for an empty list, making it obvious
to the reader and the compiler that this cannot happen.
Fixes: 79aab093a0b5 ("net: Update API for VF vlan protocol 802.1ad support")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
net/core/rtnetlink.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index 3ac8946bf244..b06d2f46b83e 100644
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -1753,6 +1753,9 @@ static int do_setvfinfo(struct net_device *dev, struct nlattr **tb)
len++;
}
+ if (len == 0)
+ return -EINVAL;
+
err = ops->ndo_set_vf_vlan(dev, ivvl[0]->vf, ivvl[0]->vlan,
ivvl[0]->qos, ivvl[0]->vlan_proto);
if (err < 0)
--
2.9.0
next reply other threads:[~2016-09-30 16:14 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-09-30 16:13 Arnd Bergmann [this message]
2016-09-30 16:23 ` [PATCH] net: rtnl: avoid uninitialized data in IFLA_VF_VLAN_LIST handling Eric Dumazet
2016-09-30 16:38 ` Arnd Bergmann
2016-10-02 9:03 ` Tariq Toukan
2016-09-30 20:12 ` Or Gerlitz
2016-10-03 5:32 ` David Miller
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