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| author | Martin KaFai Lau <martin.lau@kernel.org> | 2023-02-17 23:55:14 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2023-10-10 23:00:42 +0300 |
| commit | 8904d8848b31038b8ede40a0247a6682b0133f7a (patch) | |
| tree | ab4ad9c5d1ce6e39ba0b163bfded316e1750af06 /include/uapi/linux | |
| parent | f82aac8162871e87027692b36af335a2375d4580 (diff) | |
| download | linux-8904d8848b31038b8ede40a0247a6682b0133f7a.tar.xz | |
bpf: Add BPF_FIB_LOOKUP_SKIP_NEIGH for bpf_fib_lookup
[ Upstream commit 31de4105f00d64570139bc5494a201b0bd57349f ]
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: 5baa0433a15e ("neighbour: fix data-races around n->output")
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'include/uapi/linux')
| -rw-r--r-- | include/uapi/linux/bpf.h | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index 53bc48794719..92dbe89dafbf 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -3112,6 +3112,11 @@ union bpf_attr { * **BPF_FIB_LOOKUP_OUTPUT** * Perform lookup from an egress perspective (default is * ingress). + * **BPF_FIB_LOOKUP_SKIP_NEIGH** + * Skip the neighbour table lookup. *params*->dmac + * and *params*->smac will not be set as output. A common + * use case is to call **bpf_redirect_neigh**\ () after + * doing **bpf_fib_lookup**\ (). * * *ctx* is either **struct xdp_md** for XDP programs or * **struct sk_buff** tc cls_act programs. @@ -6678,6 +6683,7 @@ struct bpf_raw_tracepoint_args { enum { BPF_FIB_LOOKUP_DIRECT = (1U << 0), BPF_FIB_LOOKUP_OUTPUT = (1U << 1), + BPF_FIB_LOOKUP_SKIP_NEIGH = (1U << 2), }; enum { |