Commit f4e3ec0d authored May 03, 2018 by Jakub Kicinski Committed by Daniel Borkmann May 04, 2018

bpf: replace map pointer loads before calling into offloads



Offloads may find host map pointers more useful than map fds.
Map pointers can be used to identify the map, while fds are
only valid within the context of loading process.

Jump to skip_full_check on error in case verifier log overflow
has to be handled (replace_map_fd_with_map_ptr() prints to the
log, driver prep may do that too in the future).

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Reviewed-by: Jiong Wang <jiong.wang@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

parent 6cb5fb38

kernel/bpf/verifier.c

+5 −5

Original line number	Diff line number	Diff line
		@@ -5741,15 +5741,15 @@ int bpf_check(struct bpf_prog *prog, union bpf_attr attr)
		if (!IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS))
		env->strict_alignment = true;

		ret = replace_map_fd_with_map_ptr(env);
		if (ret < 0)
		goto skip_full_check;

		if (bpf_prog_is_dev_bound(env->prog->aux)) {
		ret = bpf_prog_offload_verifier_prep(env);
		if (ret)
		goto err_unlock;
		}

		ret = replace_map_fd_with_map_ptr(env);
		if (ret < 0)
		goto skip_full_check;
		}

		env->explored_states = kcalloc(env->prog->len,
		sizeof(struct bpf_verifier_state_list *),