netdevsim: Add debugfs toggle to reject BPF programs in verifier (e4ff5aa4) · Commits · 戴 / test

This adds a new debugfs toggle ('bpf_bind_verifier_accept') that can be used to make netdevsim reject BPF programs from being accepted by the verifier. If this toggle (which defaults to true) is set to false, nsim_bpf_verify_insn() will return EOPNOTSUPP on the last instruction (after outputting the 'Hello from netdevsim' verifier message). This makes it possible to check the verification callback in the driver from test_offload.py in selftests, since the verifier now clears the verifier log on a successful load, hiding the message from the driver. Fixes: ("bpf: Make verifier log more relevant by default") Signed-off-by:

Toke Høiland-Jørgensen <toke@redhat.com> Signed-off-by:

Daniel Borkmann <daniel@iogearbox.net> Acked-by:

Jakub Kicinski <kuba@kernel.org> Link: https://lore.kernel.org/bpf/160752225964.110217.12584017165318065332.stgit@toke.dk

drivers/net/netdevsim/bpf.c

+10 −2

Original line number	Diff line number	Diff line
		@@ -63,15 +63,20 @@ static int
		nsim_bpf_verify_insn(struct bpf_verifier_env *env, int insn_idx, int prev_insn)
		{
		struct nsim_bpf_bound_prog *state;
		int ret = 0;

		state = env->prog->aux->offload->dev_priv;
		if (state->nsim_dev->bpf_bind_verifier_delay && !insn_idx)
		msleep(state->nsim_dev->bpf_bind_verifier_delay);

		if (insn_idx == env->prog->len - 1)
		if (insn_idx == env->prog->len - 1) {
		pr_vlog(env, "Hello from netdevsim!\n");

		return 0;
		if (!state->nsim_dev->bpf_bind_verifier_accept)
		ret = -EOPNOTSUPP;
		}

		return ret;
		}

		static int nsim_bpf_finalize(struct bpf_verifier_env *env)
		@@ -595,6 +600,9 @@ int nsim_bpf_dev_init(struct nsim_dev *nsim_dev)
		&nsim_dev->bpf_bind_accept);
		debugfs_create_u32("bpf_bind_verifier_delay", 0600, nsim_dev->ddir,
		&nsim_dev->bpf_bind_verifier_delay);
		nsim_dev->bpf_bind_verifier_accept = true;
		debugfs_create_bool("bpf_bind_verifier_accept", 0600, nsim_dev->ddir,
		&nsim_dev->bpf_bind_verifier_accept);
		return 0;
		}

drivers/net/netdevsim/netdevsim.h

+1 −0

Original line number	Diff line number	Diff line
		@@ -189,6 +189,7 @@ struct nsim_dev {
		struct dentry *take_snapshot;
		struct bpf_offload_dev *bpf_dev;
		bool bpf_bind_accept;
		bool bpf_bind_verifier_accept;
		u32 bpf_bind_verifier_delay;
		struct dentry *ddir_bpf_bound_progs;
		u32 prog_id_gen;

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