On 3/30/23 8:17 AM, Aditi Ghag wrote:
+/* bpf_sock_destroy: Destroy the given socket with ECONNABORTED error code.
+ *
+ * The helper expects a non-NULL pointer to a socket. It invokes the
+ * protocol specific socket destroy handlers.
+ *
+ * The helper can only be called from BPF contexts that have acquired the socket
+ * locks.
+ *
+ * Parameters:
+ * @sock: Pointer to socket to be destroyed
+ *
+ * Return:
+ * On error, may return EPROTONOSUPPORT, EINVAL.
+ * EPROTONOSUPPORT if protocol specific destroy handler is not implemented.
+ * 0 otherwise
+ */
+__bpf_kfunc int bpf_sock_destroy(struct sock_common *sock)
+{
+ struct sock *sk = (struct sock *)sock;
+
+ if (!sk)
+ return -EINVAL;
+
+ /* The locking semantics that allow for synchronous execution of the
+ * destroy handlers are only supported for TCP and UDP.
+ */
+ if (!sk->sk_prot->diag_destroy || sk->sk_protocol == IPPROTO_RAW)
+ return -EOPNOTSUPP;
+
+ return sk->sk_prot->diag_destroy(sk, ECONNABORTED);
+}
+
+__diag_pop()
+
+BTF_SET8_START(sock_destroy_kfunc_set)
+BTF_ID_FLAGS(func, bpf_sock_destroy)
+BTF_SET8_END(sock_destroy_kfunc_set)
+
+static const struct btf_kfunc_id_set bpf_sock_destroy_kfunc_set = {
+ .owner = THIS_MODULE,
+ .set = &sock_destroy_kfunc_set,
+};
+
+static int init_subsystem(void)
+{
+ return register_btf_kfunc_id_set(BPF_PROG_TYPE_TRACING, &bpf_sock_destroy_kfunc_set);
This still needs to be restricted to BPF_TRACE_ITER which has held the
lock_sock. May be adding BTF_KFUNC_HOOK_TRACING_ITER. Then,
register_btf_kfunc_id_set() and btf_kfunc_id_set_contains() need to consider the
prog->expected_attach_type also?
