Commit fb9a307d authored May 31, 2017 by Chenbo Feng Committed by David S. Miller Jun 02, 2017

bpf: Allow CGROUP_SKB eBPF program to access sk_buff



This allows cgroup eBPF program to classify packet based on their
protocol or other detail information. Currently program need
CAP_NET_ADMIN privilege to attach a cgroup eBPF program, and A
process with CAP_NET_ADMIN can already see all packets on the system,
for example, by creating an iptables rules that causes the packet to
be passed to userspace via NFLOG.

Signed-off-by: Chenbo Feng <fengc@google.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

parent d0a65400

kernel/bpf/verifier.c

+1 −0

Original line number	Diff line number	Diff line
		@@ -2426,6 +2426,7 @@ static bool may_access_skb(enum bpf_prog_type type)
		case BPF_PROG_TYPE_SOCKET_FILTER:
		case BPF_PROG_TYPE_SCHED_CLS:
		case BPF_PROG_TYPE_SCHED_ACT:
		case BPF_PROG_TYPE_CGROUP_SKB:
		return true;
		default:
		return false;