lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  PHC 
Open Source and information security mailing list archives
Hash Suite for Android: free password hash cracker in your pocket
[<prev] [next>] [thread-next>] [day] [month] [year] [list]
Date:   Fri, 30 Sep 2016 18:13:49 +0200
From:   Arnd Bergmann <>
To:     "David S. Miller" <>
Cc:     Arnd Bergmann <>,
        Roopa Prabhu <>,
        Nicolas Dichtel <>,
        Nikolay Aleksandrov <>,
        Jiri Pirko <>,
        Eric Dumazet <>,
        Brenden Blanco <>,
        Hannes Frederic Sowa <>,
        Nogah Frankel <>,,
Subject: [PATCH] net: rtnl: avoid uninitialized data in IFLA_VF_VLAN_LIST handling

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

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 <>
 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)
+		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)

Powered by blists - more mailing lists