[PATCH 5.18 0185/1095] netfilter: nf_tables: add rescheduling points during loop detection walks

Greg Kroah-Hartman
2022-08-15T20:32:40Z

From: Florian Westphal <fw@strlen.de>

[ Upstream commit 81ea010667417ef3f218dfd99b69769fe66c2b67 ]

Add explicit rescheduling points during ruleset walk.

Switching to a faster algorithm is possible but this is a much
smaller change, suitable for nf tree.

Link: https://bugzilla.netfilter.org/show_bug.cgi?id=1460
Signed-off-by: Florian Westphal <fw@strlen.de>
Acked-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
net/netfilter/nf_tables_api.c | 6 ++++++
1 file changed, 6 insertions(+)

diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c
index 2b60923cf87b..7eac496961a7 100644
--- a/net/netfilter/nf_tables_api.c
+++ b/net/netfilter/nf_tables_api.c
@@ -3343,6 +3343,8 @@ int nft_chain_validate(const struct nft_ctx *ctx, const struct nft_chain *chain)
if (err < 0)
return err;
}
+
+ cond_resched();
}

return 0;
@@ -9371,9 +9373,13 @@ static int nf_tables_check_loops(const struct nft_ctx *ctx,
break;
}
}
+
+ cond_resched();
}

list_for_each_entry(set, &ctx->table->sets, list) {
+ cond_resched();
+
if (!nft_is_active_next(ctx->net, set))
continue;
if (!(set->flags & NFT_SET_MAP) ||
--
2.35.1