Re: [PATCH bpf-next] samples/bpf: check detach prog exist or not in xdp_fwd

[Toke Høiland-Jørgensen]

Zhengchao Shao <shaozhengchao@xxxxxxxxxx> writes:

> Before detach the prog, we should check detach prog exist or not.

If we're adding such a check we should also check that it's the *right*
program. I.e., query the ID for the program name and check that it
matches what the program attached, then obtain an fd and pass that as
XDP_EXPECTED_FD on detach to make sure it wasn't swapped out in the
meantime...

-Toke