netfilter: nft_set_hash: mark set element as dead when deleting from packet path

Set on the NFT_SET_ELEM_DEAD_BIT flag on this element, instead of
performing element removal which might race with an ongoing transaction.
Enable gc when dynamic flag is set on since dynset deletion requires
garbage collection after this patch.

Fixes: d0a8d877da97 ("netfilter: nft_dynset: support for element deletion")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

diff --git a/net/netfilter/nft_set_hash.c b/net/netfilter/nft_set_hash.c
index 2f067e4596b02ee1d9ab13d143bbbdecf44ba162..cef5df84600095079f003adff53de8911d6db9ba 100644 (file)
--- a/net/netfilter/nft_set_hash.c
+++ b/net/netfilter/nft_set_hash.c
@@ -249,7 +249,9 @@ static bool nft_rhash_delete(const struct nft_set *set,
        if (he == NULL)
                return false;
 
-       return rhashtable_remove_fast(&priv->ht, &he->node, nft_rhash_params) == 0;
+       nft_set_elem_dead(&he->ext);
+
+       return true;
 }
 
 static void nft_rhash_walk(const struct nft_ctx *ctx, struct nft_set *set,
@@ -412,7 +414,7 @@ static int nft_rhash_init(const struct nft_set *set,
                return err;
 
        INIT_DEFERRABLE_WORK(&priv->gc_work, nft_rhash_gc);
-       if (set->flags & NFT_SET_TIMEOUT)
+       if (set->flags & (NFT_SET_TIMEOUT | NFT_SET_EVAL))
                nft_rhash_gc_init(set);
 
        return 0;