Now it's impossible to test all branches of cgroup_skb bpf program which
accesses skb->family and skb->{local,remote}_ip{4,6} fields because they
are zeroed during socket allocation. This commit fills socket family and
addresses from related fields in constructed skb.
v2:
- fix build without CONFIG_IPV6 (kernel test robot <lkp@xxxxxxxxx>)
v3:
- check skb length before access to inet headers (Eric Dumazet)
v4:
- do not use pskb_may_pull() in skb length checking (Alexei Starovoitov)
Signed-off-by: Dmitry Yakunin <zeil@xxxxxxxxxxxxxx>
---
net/bpf/test_run.c | 21 +++++++++++++++++++++
1 file changed, 21 insertions(+)
diff --git a/net/bpf/test_run.c b/net/bpf/test_run.c
index b03c469..736a596 100644
--- a/net/bpf/test_run.c
+++ b/net/bpf/test_run.c
@@ -449,6 +449,27 @@ int bpf_prog_test_run_skb(struct bpf_prog *prog, const union bpf_attr *kattr,
skb->protocol = eth_type_trans(skb, current->nsproxy->net_ns->loopback_dev);
skb_reset_network_header(skb);
+ switch (skb->protocol) {
+ case htons(ETH_P_IP):
+ sk->sk_family = AF_INET;
+ if (sizeof(struct iphdr) <= skb_headlen(skb)) {
+ sk->sk_rcv_saddr = ip_hdr(skb)->saddr;
+ sk->sk_daddr = ip_hdr(skb)->daddr;
+ }
+ break;
+#if IS_ENABLED(CONFIG_IPV6)
+ case htons(ETH_P_IPV6):
+ sk->sk_family = AF_INET6;
+ if (sizeof(struct ipv6hdr) <= skb_headlen(skb)) {
+ sk->sk_v6_rcv_saddr = ipv6_hdr(skb)->saddr;
+ sk->sk_v6_daddr = ipv6_hdr(skb)->daddr;
+ }
+ break;
+#endif
+ default:
+ break;
+ }
+
if (is_l2)
__skb_push(skb, hh_len);
if (is_direct_pkt_access)
--
2.7.4
