netfilter: nf_tables_offload: avoid excessive stack usage

The nft_offload_ctx structure is much too large to put on the
stack:

net/netfilter/nf_tables_offload.c:31:23: error: stack frame size of 1200 bytes in function 'nft_flow_rule_create' [-Werror,-Wframe-larger-than=]

Use dynamic allocation here, as we do elsewhere in the same
function.

Fixes: c9626a2cbd ("netfilter: nf_tables: add hardware offload support")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This commit is contained in:
Arnd Bergmann 2019-09-06 17:12:30 +02:00 committed by Pablo Neira Ayuso
parent b74ae9618b
commit b44492afd2

View file

@ -30,11 +30,7 @@ static struct nft_flow_rule *nft_flow_rule_alloc(int num_actions)
struct nft_flow_rule *nft_flow_rule_create(const struct nft_rule *rule)
{
struct nft_offload_ctx ctx = {
.dep = {
.type = NFT_OFFLOAD_DEP_UNSPEC,
},
};
struct nft_offload_ctx *ctx;
struct nft_flow_rule *flow;
int num_actions = 0, err;
struct nft_expr *expr;
@ -52,21 +48,31 @@ struct nft_flow_rule *nft_flow_rule_create(const struct nft_rule *rule)
return ERR_PTR(-ENOMEM);
expr = nft_expr_first(rule);
ctx = kzalloc(sizeof(struct nft_offload_ctx), GFP_KERNEL);
if (!ctx) {
err = -ENOMEM;
goto err_out;
}
ctx->dep.type = NFT_OFFLOAD_DEP_UNSPEC;
while (expr->ops && expr != nft_expr_last(rule)) {
if (!expr->ops->offload) {
err = -EOPNOTSUPP;
goto err_out;
}
err = expr->ops->offload(&ctx, flow, expr);
err = expr->ops->offload(ctx, flow, expr);
if (err < 0)
goto err_out;
expr = nft_expr_next(expr);
}
flow->proto = ctx.dep.l3num;
flow->proto = ctx->dep.l3num;
kfree(ctx);
return flow;
err_out:
kfree(ctx);
nft_flow_rule_destroy(flow);
return ERR_PTR(err);