On Tue, 10 Nov 2020, Pablo Neira Ayuso wrote:
> Hi Casey,
>
> On Wed, Nov 04, 2020 at 04:49:17PM -0800, Casey Schaufler wrote:
> > Change netlink netfilter interfaces to use lsmcontext
> > pointers, and remove scaffolding.
> >
> > Reviewed-by: Kees Cook <keescook@xxxxxxxxxxxx>
> > Reviewed-by: John Johansen <john.johansen@xxxxxxxxxxxxx>
> > Acked-by: Stephen Smalley <sds@xxxxxxxxxxxxx>
> > Signed-off-by: Casey Schaufler <casey@xxxxxxxxxxxxxxxx>
> > Cc: netdev@xxxxxxxxxxxxxxx
> > Cc: netfilter-devel@xxxxxxxxxxxxxxx
>
> You can carry this tag in your follow up patches.
>
> Acked-by: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>
Thanks for the review!
>
> Thanks.
>
> > ---
> > net/netfilter/nfnetlink_queue.c | 37 +++++++++++++--------------------
> > 1 file changed, 14 insertions(+), 23 deletions(-)
> >
> > diff --git a/net/netfilter/nfnetlink_queue.c b/net/netfilter/nfnetlink_queue.c
> > index 84be5a49a157..0d8b83d84422 100644
> > --- a/net/netfilter/nfnetlink_queue.c
> > +++ b/net/netfilter/nfnetlink_queue.c
> > @@ -301,15 +301,13 @@ static int nfqnl_put_sk_uidgid(struct sk_buff *skb, struct sock *sk)
> > return -1;
> > }
> >
> > -static u32 nfqnl_get_sk_secctx(struct sk_buff *skb, char **secdata)
> > +static void nfqnl_get_sk_secctx(struct sk_buff *skb, struct lsmcontext *context)
> > {
> > - u32 seclen = 0;
> > #if IS_ENABLED(CONFIG_NETWORK_SECMARK)
> > struct lsmblob blob;
> > - struct lsmcontext context = { };
> >
> > if (!skb || !sk_fullsock(skb->sk))
> > - return 0;
> > + return;
> >
> > read_lock_bh(&skb->sk->sk_callback_lock);
> >
> > @@ -318,14 +316,12 @@ static u32 nfqnl_get_sk_secctx(struct sk_buff *skb, char **secdata)
> > * blob. security_secid_to_secctx() will know which security
> > * module to use to create the secctx. */
> > lsmblob_init(&blob, skb->secmark);
> > - security_secid_to_secctx(&blob, &context);
> > - *secdata = context.context;
> > + security_secid_to_secctx(&blob, context);
> > }
> >
> > read_unlock_bh(&skb->sk->sk_callback_lock);
> > - seclen = context.len;
> > #endif
> > - return seclen;
> > + return;
> > }
> >
> > static u32 nfqnl_get_bridge_size(struct nf_queue_entry *entry)
> > @@ -398,12 +394,10 @@ nfqnl_build_packet_message(struct net *net, struct nfqnl_instance *queue,
> > struct net_device *indev;
> > struct net_device *outdev;
> > struct nf_conn *ct = NULL;
> > + struct lsmcontext context = { };
> > enum ip_conntrack_info ctinfo;
> > struct nfnl_ct_hook *nfnl_ct;
> > bool csum_verify;
> > - struct lsmcontext scaff; /* scaffolding */
> > - char *secdata = NULL;
> > - u32 seclen = 0;
> >
> > size = nlmsg_total_size(sizeof(struct nfgenmsg))
> > + nla_total_size(sizeof(struct nfqnl_msg_packet_hdr))
> > @@ -469,9 +463,9 @@ nfqnl_build_packet_message(struct net *net, struct nfqnl_instance *queue,
> > }
> >
> > if ((queue->flags & NFQA_CFG_F_SECCTX) && entskb->sk) {
> > - seclen = nfqnl_get_sk_secctx(entskb, &secdata);
> > - if (seclen)
> > - size += nla_total_size(seclen);
> > + nfqnl_get_sk_secctx(entskb, &context);
> > + if (context.len)
> > + size += nla_total_size(context.len);
> > }
> >
> > skb = alloc_skb(size, GFP_ATOMIC);
> > @@ -604,7 +598,8 @@ nfqnl_build_packet_message(struct net *net, struct nfqnl_instance *queue,
> > nfqnl_put_sk_uidgid(skb, entskb->sk) < 0)
> > goto nla_put_failure;
> >
> > - if (seclen && nla_put(skb, NFQA_SECCTX, seclen, secdata))
> > + if (context.len &&
> > + nla_put(skb, NFQA_SECCTX, context.len, context.context))
> > goto nla_put_failure;
> >
> > if (ct && nfnl_ct->build(skb, ct, ctinfo, NFQA_CT, NFQA_CT_INFO) < 0)
> > @@ -632,10 +627,8 @@ nfqnl_build_packet_message(struct net *net, struct nfqnl_instance *queue,
> > }
> >
> > nlh->nlmsg_len = skb->len;
> > - if (seclen) {
> > - lsmcontext_init(&scaff, secdata, seclen, 0);
> > - security_release_secctx(&scaff);
> > - }
> > + if (context.len)
> > + security_release_secctx(&context);
> > return skb;
> >
> > nla_put_failure:
> > @@ -643,10 +636,8 @@ nfqnl_build_packet_message(struct net *net, struct nfqnl_instance *queue,
> > kfree_skb(skb);
> > net_err_ratelimited("nf_queue: error creating packet message\n");
> > nlmsg_failure:
> > - if (seclen) {
> > - lsmcontext_init(&scaff, secdata, seclen, 0);
> > - security_release_secctx(&scaff);
> > - }
> > + if (context.len)
> > + security_release_secctx(&context);
> > return NULL;
> > }
> >
> > --
> > 2.24.1
> >
>
--
James Morris
<jmorris@xxxxxxxxx>
