Commit 3f935c75 authored by Paolo Abeni's avatar Paolo Abeni Committed by David S. Miller
Browse files

inet_diag: support for wider protocol numbers 



After commit bf976514 ("sock: Make sk_protocol a 16-bit value")
the current size of 'sdiag_protocol' is not sufficient to represent
the possible protocol values.

This change introduces a new inet diag request attribute to let
user space specify the relevant protocol number using u32 values.

The attribute is parsed by inet diag core on get/dump command
and the extended protocol value, if available, is preferred to
'sdiag_protocol' to lookup the diag handler.

The parse attributed are exposed to all the diag handlers via
the cb->data.

Note that inet_diag_dump_one_icsk() is left unmodified, as it
will not be used by protocol using the extended attribute.

Suggested-by: default avatarDavid S. Miller <davem@davemloft.net>
Co-developed-by: default avatarChristoph Paasch <cpaasch@apple.com>
Signed-off-by: default avatarChristoph Paasch <cpaasch@apple.com>
Acked-by: default avatarMat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: default avatarPaolo Abeni <pabeni@redhat.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 5ca670e5

include/uapi/linux/inet_diag.h

+1 −0
Original line number Diff line number Diff line
@@ -65,6 +65,7 @@ enum { 
	INET_DIAG_REQ_NONE,

	INET_DIAG_REQ_BYTECODE,

	INET_DIAG_REQ_SK_BPF_STORAGES,

	INET_DIAG_REQ_PROTOCOL,

	__INET_DIAG_REQ_MAX,

};

net/core/sock.c

+1 −0
Original line number Diff line number Diff line
@@ -3566,6 +3566,7 @@ int sock_load_diag_module(int family, int protocol) 
#ifdef CONFIG_INET

	if (family == AF_INET &&

	    protocol != IPPROTO_RAW &&

	    protocol < MAX_INET_PROTOS &&

	    !rcu_access_pointer(inet_protos[protocol]))

		return -ENOENT;

#endif

net/ipv4/inet_diag.c

+48 −17
Original line number Diff line number Diff line
@@ -52,6 +52,11 @@ static DEFINE_MUTEX(inet_diag_table_mutex); 


static const struct inet_diag_handler *inet_diag_lock_handler(int proto)

{

	if (proto < 0 || proto >= IPPROTO_MAX) {

		mutex_lock(&inet_diag_table_mutex);

		return ERR_PTR(-ENOENT);

	}



	if (!inet_diag_table[proto])

		sock_load_diag_module(AF_INET, proto);
@@ -181,6 +186,28 @@ errout: 
}

EXPORT_SYMBOL_GPL(inet_diag_msg_attrs_fill);



static void inet_diag_parse_attrs(const struct nlmsghdr *nlh, int hdrlen,

				  struct nlattr **req_nlas)

{

	struct nlattr *nla;

	int remaining;



	nlmsg_for_each_attr(nla, nlh, hdrlen, remaining) {

		int type = nla_type(nla);



		if (type < __INET_DIAG_REQ_MAX)

			req_nlas[type] = nla;

	}

}



static int inet_diag_get_protocol(const struct inet_diag_req_v2 *req,

				  const struct inet_diag_dump_data *data)

{

	if (data->req_nlas[INET_DIAG_REQ_PROTOCOL])

		return nla_get_u32(data->req_nlas[INET_DIAG_REQ_PROTOCOL]);

	return req->sdiag_protocol;

}



#define MAX_DUMP_ALLOC_SIZE (KMALLOC_MAX_SIZE - SKB_DATA_ALIGN(sizeof(struct skb_shared_info)))



int inet_sk_diag_fill(struct sock *sk, struct inet_connection_sock *icsk,
@@ -198,7 +225,7 @@ int inet_sk_diag_fill(struct sock *sk, struct inet_connection_sock *icsk, 
	void *info = NULL;



	cb_data = cb->data;

	handler = inet_diag_table[req->sdiag_protocol];

	handler = inet_diag_table[inet_diag_get_protocol(req, cb_data)];

	BUG_ON(!handler);



	nlh = nlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
@@ -539,20 +566,25 @@ EXPORT_SYMBOL_GPL(inet_diag_dump_one_icsk); 


static int inet_diag_cmd_exact(int cmd, struct sk_buff *in_skb,

			       const struct nlmsghdr *nlh,

			       int hdrlen,

			       const struct inet_diag_req_v2 *req)

{

	const struct inet_diag_handler *handler;

	int err;

	struct inet_diag_dump_data dump_data;

	int err, protocol;



	handler = inet_diag_lock_handler(req->sdiag_protocol);

	memset(&dump_data, 0, sizeof(dump_data));

	inet_diag_parse_attrs(nlh, hdrlen, dump_data.req_nlas);

	protocol = inet_diag_get_protocol(req, &dump_data);



	handler = inet_diag_lock_handler(protocol);

	if (IS_ERR(handler)) {

		err = PTR_ERR(handler);

	} else if (cmd == SOCK_DIAG_BY_FAMILY) {

		struct inet_diag_dump_data empty_dump_data = {};

		struct netlink_callback cb = {

			.nlh = nlh,

			.skb = in_skb,

			.data = &empty_dump_data,

			.data = &dump_data,

		};

		err = handler->dump_one(&cb, req);

	} else if (cmd == SOCK_DESTROY && handler->destroy) {
@@ -1103,13 +1135,16 @@ EXPORT_SYMBOL_GPL(inet_diag_dump_icsk); 
static int __inet_diag_dump(struct sk_buff *skb, struct netlink_callback *cb,

			    const struct inet_diag_req_v2 *r)

{

	struct inet_diag_dump_data *cb_data = cb->data;

	const struct inet_diag_handler *handler;

	u32 prev_min_dump_alloc;

	int err = 0;

	int protocol, err = 0;



	protocol = inet_diag_get_protocol(r, cb_data);



again:

	prev_min_dump_alloc = cb->min_dump_alloc;

	handler = inet_diag_lock_handler(r->sdiag_protocol);

	handler = inet_diag_lock_handler(protocol);

	if (!IS_ERR(handler))

		handler->dump(skb, cb, r);

	else
@@ -1139,19 +1174,13 @@ static int __inet_diag_dump_start(struct netlink_callback *cb, int hdrlen) 
	struct inet_diag_dump_data *cb_data;

	struct sk_buff *skb = cb->skb;

	struct nlattr *nla;

	int rem, err;

	int err;



	cb_data = kzalloc(sizeof(*cb_data), GFP_KERNEL);

	if (!cb_data)

		return -ENOMEM;



	nla_for_each_attr(nla, nlmsg_attrdata(nlh, hdrlen),

			  nlmsg_attrlen(nlh, hdrlen), rem) {

		int type = nla_type(nla);



		if (type < __INET_DIAG_REQ_MAX)

			cb_data->req_nlas[type] = nla;

	}

	inet_diag_parse_attrs(nlh, hdrlen, cb_data->req_nlas);



	nla = cb_data->inet_diag_nla_bc;

	if (nla) {
@@ -1237,7 +1266,8 @@ static int inet_diag_get_exact_compat(struct sk_buff *in_skb, 
	req.idiag_states = rc->idiag_states;

	req.id = rc->id;



	return inet_diag_cmd_exact(SOCK_DIAG_BY_FAMILY, in_skb, nlh, &req);

	return inet_diag_cmd_exact(SOCK_DIAG_BY_FAMILY, in_skb, nlh,

				   sizeof(struct inet_diag_req), &req);

}



static int inet_diag_rcv_msg_compat(struct sk_buff *skb, struct nlmsghdr *nlh)
@@ -1279,7 +1309,8 @@ static int inet_diag_handler_cmd(struct sk_buff *skb, struct nlmsghdr *h) 
		return netlink_dump_start(net->diag_nlsk, skb, h, &c);

	}



	return inet_diag_cmd_exact(h->nlmsg_type, skb, h, nlmsg_data(h));

	return inet_diag_cmd_exact(h->nlmsg_type, skb, h, hdrlen,

				   nlmsg_data(h));

}



static

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