The bpf_ksock_send() kfunc eventually calls security_socket_sendmsg(),
thus creating a possible recursion if a program calling the kfunc is
attached on that specific hook. A filter is added on the kfunc
registration to prevent that at load time from the verifier. This test
exercises that the verifier will reject such program on that attach
point.
Signed-off-by: Mahe Tardy <mahe.tardy@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Acked-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/bpf/20260813110540.103550-5-mahe.tardy@gmail.com
Add a selftest that exercises the ksock kfuncs end-to-end. One syscall
BPF setup program creates a ksock context and connects the socket.
Another LSM sleepable BPF program looks up the context and send test
data. The userspace harness creates a network namespace and a new socket
on loopback, run the setup syscall prog and send LSM BPF prog then check
that the userspace socket received the data from BPF.
Signed-off-by: Mahe Tardy <mahe.tardy@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Jiayuan Chen <jiayuan.chen@linux.dev>
Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Link: https://lore.kernel.org/bpf/20260813110540.103550-4-mahe.tardy@gmail.com
