[PATCH 5.4 015/203] netfilter: nft_flow_offload: fix underflow in flowtable reference counter

From: Greg Kroah-Hartman
Date: Thu Jan 16 2020 - 18:20:29 EST


From: wenxu <wenxu@xxxxxxxxx>

commit 8ca79606cdfde2e37ee4f0707b9d1874a6f0eb38 upstream.

The .deactivate and .activate interfaces already deal with the reference
counter. Otherwise, this results in spurious "Device is busy" errors.

Fixes: a3c90f7a2323 ("netfilter: nf_tables: flow offload expression")
Signed-off-by: wenxu <wenxu@xxxxxxxxx>
Signed-off-by: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
net/netfilter/nft_flow_offload.c | 3 ---
1 file changed, 3 deletions(-)

--- a/net/netfilter/nft_flow_offload.c
+++ b/net/netfilter/nft_flow_offload.c
@@ -197,9 +197,6 @@ static void nft_flow_offload_activate(co
static void nft_flow_offload_destroy(const struct nft_ctx *ctx,
const struct nft_expr *expr)
{
- struct nft_flow_offload *priv = nft_expr_priv(expr);
-
- priv->flowtable->use--;
nf_ct_netns_put(ctx->net, ctx->family);
}