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| author | Hou Tao <houtao1@huawei.com> | 2024-12-06 19:06:16 +0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2024-12-14 20:03:19 +0100 |
| commit | 81ec3c6ceb7c9e67aeed32efff97009362088b8a (patch) | |
| tree | 2d90630efbfa0a88fb39b9c9f3bb93639c8ff669 /kernel/bpf | |
| parent | 0d8658c0cb599a5a2de809f88e335072c38d463d (diff) | |
| download | linux-81ec3c6ceb7c9e67aeed32efff97009362088b8a.tar.gz linux-81ec3c6ceb7c9e67aeed32efff97009362088b8a.tar.bz2 linux-81ec3c6ceb7c9e67aeed32efff97009362088b8a.zip | |
bpf: Handle BPF_EXIST and BPF_NOEXIST for LPM trie
[ Upstream commit eae6a075e9537dd69891cf77ca5a88fa8a28b4a1 ]
Add the currently missing handling for the BPF_EXIST and BPF_NOEXIST
flags. These flags can be specified by users and are relevant since LPM
trie supports exact matches during update.
Fixes: b95a5c4db09b ("bpf: add a longest prefix match trie map implementation")
Reviewed-by: Toke Høiland-Jørgensen <toke@redhat.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Hou Tao <houtao1@huawei.com>
Link: https://lore.kernel.org/r/20241206110622.1161752-4-houtao@huaweicloud.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'kernel/bpf')
| -rw-r--r-- | kernel/bpf/lpm_trie.c | 23 |
1 files changed, 20 insertions, 3 deletions
diff --git a/kernel/bpf/lpm_trie.c b/kernel/bpf/lpm_trie.c index 9b60eda0f727..a82cf3693778 100644 --- a/kernel/bpf/lpm_trie.c +++ b/kernel/bpf/lpm_trie.c @@ -376,6 +376,10 @@ static long trie_update_elem(struct bpf_map *map, * simply assign the @new_node to that slot and be done. */ if (!node) { + if (flags == BPF_EXIST) { + ret = -ENOENT; + goto out; + } rcu_assign_pointer(*slot, new_node); goto out; } @@ -384,18 +388,31 @@ static long trie_update_elem(struct bpf_map *map, * which already has the correct data array set. */ if (node->prefixlen == matchlen) { + if (!(node->flags & LPM_TREE_NODE_FLAG_IM)) { + if (flags == BPF_NOEXIST) { + ret = -EEXIST; + goto out; + } + trie->n_entries--; + } else if (flags == BPF_EXIST) { + ret = -ENOENT; + goto out; + } + new_node->child[0] = node->child[0]; new_node->child[1] = node->child[1]; - if (!(node->flags & LPM_TREE_NODE_FLAG_IM)) - trie->n_entries--; - rcu_assign_pointer(*slot, new_node); free_node = node; goto out; } + if (flags == BPF_EXIST) { + ret = -ENOENT; + goto out; + } + /* If the new node matches the prefix completely, it must be inserted * as an ancestor. Simply insert it between @node and *@slot. */ |