xdp: XDP_REDIRECT should check IFF_UP and MTU

Otherwise we end up with attempting to send packets from down devices
or to send oversized packets, which may cause unexpected driver/device
behaviour. Generic XDP has already done this check, so reuse the logic
in native XDP.

Fixes: 814abfabef ("xdp: add bpf_redirect helper function")
Signed-off-by: Toshiaki Makita <makita.toshiaki@lab.ntt.co.jp>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
This commit is contained in:
Toshiaki Makita
2018-07-06 11:49:00 +09:00
committed by Alexei Starovoitov
parent 4fb126cbcb
commit d8d7218ad8
3 changed files with 16 additions and 6 deletions

View File

@@ -765,8 +765,8 @@ static inline bool bpf_dump_raw_ok(void)
struct bpf_prog *bpf_patch_insn_single(struct bpf_prog *prog, u32 off,
const struct bpf_insn *patch, u32 len);
static inline int __xdp_generic_ok_fwd_dev(struct sk_buff *skb,
struct net_device *fwd)
static inline int xdp_ok_fwd_dev(const struct net_device *fwd,
unsigned int pktlen)
{
unsigned int len;
@@ -774,7 +774,7 @@ static inline int __xdp_generic_ok_fwd_dev(struct sk_buff *skb,
return -ENETDOWN;
len = fwd->mtu + fwd->hard_header_len + VLAN_HLEN;
if (skb->len > len)
if (pktlen > len)
return -EMSGSIZE;
return 0;