bpf: allow access to skb->len from offloads

Since we are now doing strict checking of what offloads
may access, make sure skb->len is on that list.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/core/filter.c b/net/core/filter.c
index 7373a08..09e011f 100644 (file)
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -3738,6 +3738,8 @@ tc_cls_act_is_valid_access_analyzer(int off, int size,
                                    struct bpf_insn_access_aux *info)
 {
        switch (off) {
+       case offsetof(struct sk_buff, len):
+               return true;
        case offsetof(struct sk_buff, data):
                info->reg_type = PTR_TO_PACKET;
                return true;