bpf: Add BPF_FIB_LOOKUP_SKIP_NEIGH for bpf_fib_lookup
[ Upstream commit 31de4105 ] The bpf_fib_lookup() also looks up the neigh table. This was done before bpf_redirect_neigh() was added. In the use case that does not manage the neigh table and requires bpf_fib_lookup() to lookup a fib to decide if it needs to redirect or not, the bpf prog can depend only on using bpf_redirect_neigh() to lookup the neigh. It also keeps the neigh entries fresh and connected. This patch adds a bpf_fib_lookup flag, SKIP_NEIGH, to avoid the double neigh lookup when the bpf prog always call bpf_redirect_neigh() to do the neigh lookup. The params->smac output is skipped together when SKIP_NEIGH is set because bpf_redirect_neigh() will figure out the smac also. Signed-off-by:Martin KaFai Lau <martin.lau@kernel.org> Signed-off-by:
Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20230217205515.3583372-1-martin.lau@linux.dev Stable-dep-of: 5baa0433 ("neighbour: fix data-races around n->output") Signed-off-by:
Sasha Levin <sashal@kernel.org>
parent
f82aac81
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