Hi Florian,
El 19 de agosto de 2019 13:55:27 CEST, Florian Westphal <fw@xxxxxxxxx> escribió:
>Fernando Fernandez Mancera <ffmancera@xxxxxxxxxx> wrote:
>> This is a WIP patch version. I still having some issues in userspace
>but I
>> would like to get feedback about the kernel-side patch. Thanks!
>>
>> Signed-off-by: Fernando Fernandez Mancera <ffmancera@xxxxxxxxxx>
>> ---
>> include/net/netfilter/nf_tables.h | 6 +++
>> net/netfilter/nf_tables_api.c | 73
>++++++++++++++++++++++++++++---
>> 2 files changed, 72 insertions(+), 7 deletions(-)
>>
>> diff --git a/include/net/netfilter/nf_tables.h
>b/include/net/netfilter/nf_tables.h
>> index dc301e3d6739..dc4e32040ea9 100644
>> --- a/include/net/netfilter/nf_tables.h
>> +++ b/include/net/netfilter/nf_tables.h
>> @@ -1123,6 +1123,9 @@ struct nft_object_ops {
>> int (*dump)(struct sk_buff *skb,
>> struct nft_object *obj,
>> bool reset);
>> + int (*update)(const struct nft_ctx *ctx,
>> + const struct nlattr *const tb[],
>> + struct nft_object *obj);
>> const struct nft_object_type *type;
>> };
>>
>> @@ -1405,10 +1408,13 @@ struct nft_trans_elem {
>>
>> struct nft_trans_obj {
>> struct nft_object *obj;
>> + bool update;
>> };
>>
>> #define nft_trans_obj(trans) \
>> (((struct nft_trans_obj *)trans->data)->obj)
>> +#define nft_trans_obj_update(trans) \
>> + (((struct nft_trans_obj *)trans->data)->update)
>>
>> struct nft_trans_flowtable {
>> struct nft_flowtable *flowtable;
>> diff --git a/net/netfilter/nf_tables_api.c
>b/net/netfilter/nf_tables_api.c
>> index fe3b7b0c6c66..d7b94904599c 100644
>> --- a/net/netfilter/nf_tables_api.c
>> +++ b/net/netfilter/nf_tables_api.c
>> @@ -5122,6 +5122,48 @@ nft_obj_type_get(struct net *net, u32 objtype)
>> return ERR_PTR(-ENOENT);
>> }
>>
>> +static int nf_tables_updobj(const struct nft_ctx *ctx,
>> + const struct nft_object_type *type,
>> + const struct nlattr *attr,
>> + struct nft_object *obj)
>> +{
>> + struct nft_trans *trans;
>> + struct nlattr **tb;
>> + int err = -ENOMEM;
>> +
>> + trans = nft_trans_alloc(ctx, NFT_MSG_NEWOBJ,
>> + sizeof(struct nft_trans_obj));
>> + if (!trans)
>> + return -ENOMEM;
>> +
>> + tb = kmalloc_array(type->maxattr + 1, sizeof(*tb), GFP_KERNEL);
>
>You can use kcalloc here and then remove the memset().
>p
>> + err = obj->ops->update(ctx, (const struct nlattr * const *)tb,
>obj);
>> + if (err < 0)
>> + goto err;
>
>This looks wrong, see below.
>
>> @@ -5161,7 +5203,13 @@ static int nf_tables_newobj(struct net *net,
>struct sock *nlsk,
>> NL_SET_BAD_ATTR(extack, nla[NFTA_OBJ_NAME]);
>> return -EEXIST;
>> }
>> - return 0;
>> + if (nlh->nlmsg_flags & NLM_F_REPLACE)
>> + return -EOPNOTSUPP;
>> +
>> + type = nft_obj_type_get(net, objtype);
>> + nft_ctx_init(&ctx, net, skb, nlh, family, table, NULL, nla);
>> +
>> + return nf_tables_updobj(&ctx, type, nla[NFTA_OBJ_DATA], obj);
>> }
>>
>> case NFT_MSG_NEWOBJ:
>> - nft_clear(net, nft_trans_obj(trans));
>> - nf_tables_obj_notify(&trans->ctx, nft_trans_obj(trans),
>> - NFT_MSG_NEWOBJ);
>> - nft_trans_destroy(trans);
>> + if (nft_trans_obj_update(trans)) {
>> + nf_tables_obj_notify(&trans->ctx,
>> + nft_trans_obj(trans),
>> + NFT_MSG_NEWOBJ);
>
>I would have expected the ->update() here, when committing the batch.
>Under what conditions can an update() fail?
It depends on the object type. In the quota case it can fail if the quota have invalid values.
