rtnetlink: fix rtnl_vfinfo_size

commit 7e75f74a171a8146cc3ee92d5562878b40c25fb5 upstream.

The size reported by rtnl_vfinfo_size doesn't match the space used by
rtnl_fill_vfinfo.

rtnl_vfinfo_size currently doesn't account for the nest attributes
used by statistics (added in commit 3b766cd83232), nor for struct
ifla_vf_tx_rate (since commit ed616689a3d9, which added ifla_vf_rate
to the dump without removing ifla_vf_tx_rate, but replaced
ifla_vf_tx_rate with ifla_vf_rate in the size computation).

Fixes: 3b766cd83232 ("net/core: Add reading VF statistics through the PF netdevice")
Fixes: ed616689a3d9 ("net-next:v4: Add support to configure SR-IOV VF minimum and maximum Tx rate through ip tool")
Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
[bwh: Backported to 3.16: only need to add space for IFLA_VF_TX_RATE]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index 7544529999751aa412d86bdf2f671d6ada3ad1bc..96e9c5f517042dd2962fb2b2a054f0b171b30a66 100644 (file)
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -794,12 +794,13 @@ static inline int rtnl_vfinfo_size(const struct net_device *dev,
        if (dev->dev.parent && dev_is_pci(dev->dev.parent) &&
            (ext_filter_mask & RTEXT_FILTER_VF)) {
                int num_vfs = dev_num_vf(dev->dev.parent);
-               size_t size = nla_total_size(sizeof(struct nlattr));
-               size += nla_total_size(num_vfs * sizeof(struct nlattr));
+               size_t size = nla_total_size(0);
                size += num_vfs *
-                       (nla_total_size(sizeof(struct ifla_vf_mac)) +
+                       (nla_total_size(0) +
+                        nla_total_size(sizeof(struct ifla_vf_mac)) +
                         nla_total_size(sizeof(struct ifla_vf_vlan)) +
                         nla_total_size(sizeof(struct ifla_vf_spoofchk)) +
+                        nla_total_size(sizeof(struct ifla_vf_tx_rate)) +
                         nla_total_size(sizeof(struct ifla_vf_rate)) +
                         nla_total_size(sizeof(struct ifla_vf_link_state)));
                return size;