net: act_bpf: fix size mismatch on filter preparation

Similarly as in cls_bpf, also this code needs to reject mismatches.

Reference: http://article.gmane.org/gmane.linux.network/347406
Fixes: d23b8ad8ab23 ("tc: add BPF based action")
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Acked-by: Jiri Pirko <jiri@resnulli.us>
Acked-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 3 insertions, 0 deletions

diff --git a/net/sched/act_bpf.c b/net/sched/act_bpf.c
index 1bd257e473a9..82c5d7fc1988 100644
--- a/net/sched/act_bpf.c
+++ b/net/sched/act_bpf.c
@@ -122,6 +122,9 @@ static int tcf_bpf_init(struct net *net, struct nlattr *nla,
                 return -EINVAL;
 
         bpf_size = bpf_num_ops * sizeof(*bpf_ops);
+        if (bpf_size != nla_len(tb[TCA_ACT_BPF_OPS]))
+                return -EINVAL;
+
         bpf_ops = kzalloc(bpf_size, GFP_KERNEL);
         if (!bpf_ops)
                 return -ENOMEM;