netfilter: nf_tables: nft_obj_filter fits into cb->ctx

[ Upstream commit 5a893b9cdf ]

No need to allocate it if one may just use struct netlink_callback's
scratch area for it.

Signed-off-by: Phil Sutter <phil@nwl.cc>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Stable-dep-of: bd662c4218 ("netfilter: nf_tables: Add locking for NFT_MSG_GETOBJ_RESET requests")
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Phil Sutter 2023-10-20 19:34:32 +02:00 committed by Greg Kroah-Hartman
parent 959c9bf85f
commit f3b7dc8b6c

View File

@ -7726,7 +7726,7 @@ struct nft_obj_dump_ctx {
static int nf_tables_dump_obj(struct sk_buff *skb, struct netlink_callback *cb)
{
const struct nfgenmsg *nfmsg = nlmsg_data(cb->nlh);
struct nft_obj_dump_ctx *ctx = cb->data;
struct nft_obj_dump_ctx *ctx = (void *)cb->ctx;
struct net *net = sock_net(skb->sk);
int family = nfmsg->nfgen_family;
struct nftables_pernet *nft_net;
@ -7788,34 +7788,28 @@ cont:
static int nf_tables_dump_obj_start(struct netlink_callback *cb)
{
struct nft_obj_dump_ctx *ctx = (void *)cb->ctx;
const struct nlattr * const *nla = cb->data;
struct nft_obj_dump_ctx *ctx = NULL;
ctx = kzalloc(sizeof(*ctx), GFP_ATOMIC);
if (!ctx)
return -ENOMEM;
BUILD_BUG_ON(sizeof(*ctx) > sizeof(cb->ctx));
if (nla[NFTA_OBJ_TABLE]) {
ctx->table = nla_strdup(nla[NFTA_OBJ_TABLE], GFP_ATOMIC);
if (!ctx->table) {
kfree(ctx);
if (!ctx->table)
return -ENOMEM;
}
}
if (nla[NFTA_OBJ_TYPE])
ctx->type = ntohl(nla_get_be32(nla[NFTA_OBJ_TYPE]));
cb->data = ctx;
return 0;
}
static int nf_tables_dump_obj_done(struct netlink_callback *cb)
{
struct nft_obj_dump_ctx *ctx = cb->data;
struct nft_obj_dump_ctx *ctx = (void *)cb->ctx;
kfree(ctx->table);
kfree(ctx);
return 0;
}