v4.19.13 snapshot.
diff --git a/samples/bpf/sock_flags_kern.c b/samples/bpf/sock_flags_kern.c
new file mode 100644
index 0000000..05dcdf8
--- /dev/null
+++ b/samples/bpf/sock_flags_kern.c
@@ -0,0 +1,49 @@
+#include <uapi/linux/bpf.h>
+#include <linux/socket.h>
+#include <linux/net.h>
+#include <uapi/linux/in.h>
+#include <uapi/linux/in6.h>
+#include "bpf_helpers.h"
+
+SEC("cgroup/sock1")
+int bpf_prog1(struct bpf_sock *sk)
+{
+ char fmt[] = "socket: family %d type %d protocol %d\n";
+ char fmt2[] = "socket: uid %u gid %u\n";
+ __u64 gid_uid = bpf_get_current_uid_gid();
+ __u32 uid = gid_uid & 0xffffffff;
+ __u32 gid = gid_uid >> 32;
+
+ bpf_trace_printk(fmt, sizeof(fmt), sk->family, sk->type, sk->protocol);
+ bpf_trace_printk(fmt2, sizeof(fmt2), uid, gid);
+
+ /* block PF_INET6, SOCK_RAW, IPPROTO_ICMPV6 sockets
+ * ie., make ping6 fail
+ */
+ if (sk->family == PF_INET6 &&
+ sk->type == SOCK_RAW &&
+ sk->protocol == IPPROTO_ICMPV6)
+ return 0;
+
+ return 1;
+}
+
+SEC("cgroup/sock2")
+int bpf_prog2(struct bpf_sock *sk)
+{
+ char fmt[] = "socket: family %d type %d protocol %d\n";
+
+ bpf_trace_printk(fmt, sizeof(fmt), sk->family, sk->type, sk->protocol);
+
+ /* block PF_INET, SOCK_RAW, IPPROTO_ICMP sockets
+ * ie., make ping fail
+ */
+ if (sk->family == PF_INET &&
+ sk->type == SOCK_RAW &&
+ sk->protocol == IPPROTO_ICMP)
+ return 0;
+
+ return 1;
+}
+
+char _license[] SEC("license") = "GPL";