Commit 5682d393 authored by Martin KaFai Lau's avatar Martin KaFai Lau Committed by Alexei Starovoitov
Browse files

inet_diag: Refactor inet_sk_diag_fill(), dump(), and dump_one() 



In a latter patch, there is a need to update "cb->min_dump_alloc"
in inet_sk_diag_fill() as it learns the diffierent bpf_sk_storages
stored in a sk while dumping all sk(s) (e.g. tcp_hashinfo).

The inet_sk_diag_fill() currently does not take the "cb" as an argument.
One of the reason is inet_sk_diag_fill() is used by both dump_one()
and dump() (which belong to the "struct inet_diag_handler".  The dump_one()
interface does not pass the "cb" along.

This patch is to make dump_one() pass a "cb".  The "cb" is created in
inet_diag_cmd_exact().  The "nlh" and "in_skb" are stored in "cb" as
the dump() interface does.  The total number of args in
inet_sk_diag_fill() is also cut from 10 to 7 and
that helps many callers to pass fewer args.

In particular,
"struct user_namespace *user_ns", "u32 pid", and "u32 seq"
can be replaced by accessing "cb->nlh" and "cb->skb".

A similar argument reduction is also made to
inet_twsk_diag_fill() and inet_req_diag_fill().

inet_csk_diag_dump() and inet_csk_diag_fill() are also removed.
They are mostly equivalent to inet_sk_diag_fill().  Their repeated
usages are very limited.  Thus, inet_sk_diag_fill() is directly used
in those occasions.

Signed-off-by: default avatarMartin KaFai Lau <kafai@fb.com>
Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
Acked-by: default avatarSong Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20200225230409.1975173-1-kafai@fb.com
parent d7f10df8

include/linux/inet_diag.h

+5 −7
Original line number Diff line number Diff line
@@ -18,8 +18,7 @@ struct inet_diag_handler { 
				const struct inet_diag_req_v2 *r,

				struct nlattr *bc);



	int		(*dump_one)(struct sk_buff *in_skb,

				    const struct nlmsghdr *nlh,

	int		(*dump_one)(struct netlink_callback *cb,

				    const struct inet_diag_req_v2 *req);



	void		(*idiag_get_info)(struct sock *sk,
@@ -42,16 +41,15 @@ struct inet_diag_handler { 


struct inet_connection_sock;

int inet_sk_diag_fill(struct sock *sk, struct inet_connection_sock *icsk,

		      struct sk_buff *skb, const struct inet_diag_req_v2 *req,

		      struct user_namespace *user_ns,

		      u32 pid, u32 seq, u16 nlmsg_flags,

		      const struct nlmsghdr *unlh, bool net_admin);

		      struct sk_buff *skb, struct netlink_callback *cb,

		      const struct inet_diag_req_v2 *req,

		      u16 nlmsg_flags, bool net_admin);

void inet_diag_dump_icsk(struct inet_hashinfo *h, struct sk_buff *skb,

			 struct netlink_callback *cb,

			 const struct inet_diag_req_v2 *r,

			 struct nlattr *bc);

int inet_diag_dump_one_icsk(struct inet_hashinfo *hashinfo,

			    struct sk_buff *in_skb, const struct nlmsghdr *nlh,

			    struct netlink_callback *cb,

			    const struct inet_diag_req_v2 *req);



struct sock *inet_diag_find_one_icsk(struct net *net,

net/dccp/diag.c

+2 −3
Original line number Diff line number Diff line
@@ -51,11 +51,10 @@ static void dccp_diag_dump(struct sk_buff *skb, struct netlink_callback *cb, 
	inet_diag_dump_icsk(&dccp_hashinfo, skb, cb, r, bc);

}



static int dccp_diag_dump_one(struct sk_buff *in_skb,

			      const struct nlmsghdr *nlh,

static int dccp_diag_dump_one(struct netlink_callback *cb,

			      const struct inet_diag_req_v2 *req)

{

	return inet_diag_dump_one_icsk(&dccp_hashinfo, in_skb, nlh, req);

	return inet_diag_dump_one_icsk(&dccp_hashinfo, cb, req);

}



static const struct inet_diag_handler dccp_diag_handler = {

net/ipv4/inet_diag.c

+44 −72
Original line number Diff line number Diff line
@@ -157,11 +157,9 @@ errout: 
EXPORT_SYMBOL_GPL(inet_diag_msg_attrs_fill);



int inet_sk_diag_fill(struct sock *sk, struct inet_connection_sock *icsk,

		      struct sk_buff *skb, const struct inet_diag_req_v2 *req,

		      struct user_namespace *user_ns,

		      u32 portid, u32 seq, u16 nlmsg_flags,

		      const struct nlmsghdr *unlh,

		      bool net_admin)

		      struct sk_buff *skb, struct netlink_callback *cb,

		      const struct inet_diag_req_v2 *req,

		      u16 nlmsg_flags, bool net_admin)

{

	const struct tcp_congestion_ops *ca_ops;

	const struct inet_diag_handler *handler;
@@ -174,8 +172,8 @@ int inet_sk_diag_fill(struct sock *sk, struct inet_connection_sock *icsk, 
	handler = inet_diag_table[req->sdiag_protocol];

	BUG_ON(!handler);



	nlh = nlmsg_put(skb, portid, seq, unlh->nlmsg_type, sizeof(*r),

			nlmsg_flags);

	nlh = nlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,

			cb->nlh->nlmsg_type, sizeof(*r), nlmsg_flags);

	if (!nlh)

		return -EMSGSIZE;
@@ -187,7 +185,9 @@ int inet_sk_diag_fill(struct sock *sk, struct inet_connection_sock *icsk, 
	r->idiag_timer = 0;

	r->idiag_retrans = 0;



	if (inet_diag_msg_attrs_fill(sk, skb, r, ext, user_ns, net_admin))

	if (inet_diag_msg_attrs_fill(sk, skb, r, ext,

				     sk_user_ns(NETLINK_CB(cb->skb).sk),

				     net_admin))

		goto errout;



	if (ext & (1 << (INET_DIAG_MEMINFO - 1))) {
@@ -312,30 +312,19 @@ errout: 
}

EXPORT_SYMBOL_GPL(inet_sk_diag_fill);



static int inet_csk_diag_fill(struct sock *sk,

			      struct sk_buff *skb,

			      const struct inet_diag_req_v2 *req,

			      struct user_namespace *user_ns,

			      u32 portid, u32 seq, u16 nlmsg_flags,

			      const struct nlmsghdr *unlh,

			      bool net_admin)

{

	return inet_sk_diag_fill(sk, inet_csk(sk), skb, req, user_ns,

				 portid, seq, nlmsg_flags, unlh, net_admin);

}



static int inet_twsk_diag_fill(struct sock *sk,

			       struct sk_buff *skb,

			       u32 portid, u32 seq, u16 nlmsg_flags,

			       const struct nlmsghdr *unlh)

			       struct netlink_callback *cb,

			       u16 nlmsg_flags)

{

	struct inet_timewait_sock *tw = inet_twsk(sk);

	struct inet_diag_msg *r;

	struct nlmsghdr *nlh;

	long tmo;



	nlh = nlmsg_put(skb, portid, seq, unlh->nlmsg_type, sizeof(*r),

			nlmsg_flags);

	nlh = nlmsg_put(skb, NETLINK_CB(cb->skb).portid,

			cb->nlh->nlmsg_seq, cb->nlh->nlmsg_type,

			sizeof(*r), nlmsg_flags);

	if (!nlh)

		return -EMSGSIZE;
@@ -359,16 +348,16 @@ static int inet_twsk_diag_fill(struct sock *sk, 
}



static int inet_req_diag_fill(struct sock *sk, struct sk_buff *skb,

			      u32 portid, u32 seq, u16 nlmsg_flags,

			      const struct nlmsghdr *unlh, bool net_admin)

			      struct netlink_callback *cb,

			      u16 nlmsg_flags, bool net_admin)

{

	struct request_sock *reqsk = inet_reqsk(sk);

	struct inet_diag_msg *r;

	struct nlmsghdr *nlh;

	long tmo;



	nlh = nlmsg_put(skb, portid, seq, unlh->nlmsg_type, sizeof(*r),

			nlmsg_flags);

	nlh = nlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,

			cb->nlh->nlmsg_type, sizeof(*r), nlmsg_flags);

	if (!nlh)

		return -EMSGSIZE;
@@ -397,21 +386,18 @@ static int inet_req_diag_fill(struct sock *sk, struct sk_buff *skb, 
}



static int sk_diag_fill(struct sock *sk, struct sk_buff *skb,

			struct netlink_callback *cb,

			const struct inet_diag_req_v2 *r,

			struct user_namespace *user_ns,

			u32 portid, u32 seq, u16 nlmsg_flags,

			const struct nlmsghdr *unlh, bool net_admin)

			u16 nlmsg_flags, bool net_admin)

{

	if (sk->sk_state == TCP_TIME_WAIT)

		return inet_twsk_diag_fill(sk, skb, portid, seq,

					   nlmsg_flags, unlh);

		return inet_twsk_diag_fill(sk, skb, cb, nlmsg_flags);



	if (sk->sk_state == TCP_NEW_SYN_RECV)

		return inet_req_diag_fill(sk, skb, portid, seq,

					  nlmsg_flags, unlh, net_admin);

		return inet_req_diag_fill(sk, skb, cb, nlmsg_flags, net_admin);



	return inet_csk_diag_fill(sk, skb, r, user_ns, portid, seq,

				  nlmsg_flags, unlh, net_admin);

	return inet_sk_diag_fill(sk, inet_csk(sk), skb, cb, r, nlmsg_flags,

				 net_admin);

}



struct sock *inet_diag_find_one_icsk(struct net *net,
@@ -459,10 +445,10 @@ struct sock *inet_diag_find_one_icsk(struct net *net, 
EXPORT_SYMBOL_GPL(inet_diag_find_one_icsk);



int inet_diag_dump_one_icsk(struct inet_hashinfo *hashinfo,

			    struct sk_buff *in_skb,

			    const struct nlmsghdr *nlh,

			    struct netlink_callback *cb,

			    const struct inet_diag_req_v2 *req)

{

	struct sk_buff *in_skb = cb->skb;

	bool net_admin = netlink_net_capable(in_skb, CAP_NET_ADMIN);

	struct net *net = sock_net(in_skb->sk);

	struct sk_buff *rep;
@@ -479,10 +465,7 @@ int inet_diag_dump_one_icsk(struct inet_hashinfo *hashinfo, 
		goto out;

	}



	err = sk_diag_fill(sk, rep, req,

			   sk_user_ns(NETLINK_CB(in_skb).sk),

			   NETLINK_CB(in_skb).portid,

			   nlh->nlmsg_seq, 0, nlh, net_admin);

	err = sk_diag_fill(sk, rep, cb, req, 0, net_admin);

	if (err < 0) {

		WARN_ON(err == -EMSGSIZE);

		nlmsg_free(rep);
@@ -509,14 +492,19 @@ static int inet_diag_cmd_exact(int cmd, struct sk_buff *in_skb, 
	int err;



	handler = inet_diag_lock_handler(req->sdiag_protocol);

	if (IS_ERR(handler))

	if (IS_ERR(handler)) {

		err = PTR_ERR(handler);

	else if (cmd == SOCK_DIAG_BY_FAMILY)

		err = handler->dump_one(in_skb, nlh, req);

	else if (cmd == SOCK_DESTROY && handler->destroy)

	} else if (cmd == SOCK_DIAG_BY_FAMILY) {

		struct netlink_callback cb = {

			.nlh = nlh,

			.skb = in_skb,

		};

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

	} else if (cmd == SOCK_DESTROY && handler->destroy) {

		err = handler->destroy(in_skb, req);

	else

	} else {

		err = -EOPNOTSUPP;

	}

	inet_diag_unlock_handler(handler);



	return err;
@@ -847,23 +835,6 @@ static int inet_diag_bc_audit(const struct nlattr *attr, 
	return len == 0 ? 0 : -EINVAL;

}



static int inet_csk_diag_dump(struct sock *sk,

			      struct sk_buff *skb,

			      struct netlink_callback *cb,

			      const struct inet_diag_req_v2 *r,

			      const struct nlattr *bc,

			      bool net_admin)

{

	if (!inet_diag_bc_sk(bc, sk))

		return 0;



	return inet_csk_diag_fill(sk, skb, r,

				  sk_user_ns(NETLINK_CB(cb->skb).sk),

				  NETLINK_CB(cb->skb).portid,

				  cb->nlh->nlmsg_seq, NLM_F_MULTI, cb->nlh,

				  net_admin);

}



static void twsk_build_assert(void)

{

	BUILD_BUG_ON(offsetof(struct inet_timewait_sock, tw_family) !=
@@ -935,8 +906,12 @@ void inet_diag_dump_icsk(struct inet_hashinfo *hashinfo, struct sk_buff *skb, 
				    r->id.idiag_sport)

					goto next_listen;



				if (inet_csk_diag_dump(sk, skb, cb, r,

						       bc, net_admin) < 0) {

				if (!inet_diag_bc_sk(bc, sk))

					goto next_listen;



				if (inet_sk_diag_fill(sk, inet_csk(sk), skb,

						      cb, r, NLM_F_MULTI,

						      net_admin) < 0) {

					spin_unlock(&ilb->lock);

					goto done;

				}
@@ -1014,11 +989,8 @@ next_normal: 
		res = 0;

		for (idx = 0; idx < accum; idx++) {

			if (res >= 0) {

				res = sk_diag_fill(sk_arr[idx], skb, r,

					   sk_user_ns(NETLINK_CB(cb->skb).sk),

					   NETLINK_CB(cb->skb).portid,

					   cb->nlh->nlmsg_seq, NLM_F_MULTI,

					   cb->nlh, net_admin);

				res = sk_diag_fill(sk_arr[idx], skb, cb, r,

						   NLM_F_MULTI, net_admin);

				if (res < 0)

					num = num_arr[idx];

			}

net/ipv4/raw_diag.c

+6 −12
Original line number Diff line number Diff line
@@ -87,15 +87,16 @@ out_unlock: 
	return sk ? sk : ERR_PTR(-ENOENT);

}



static int raw_diag_dump_one(struct sk_buff *in_skb,

			     const struct nlmsghdr *nlh,

static int raw_diag_dump_one(struct netlink_callback *cb,

			     const struct inet_diag_req_v2 *r)

{

	struct net *net = sock_net(in_skb->sk);

	struct sk_buff *in_skb = cb->skb;

	struct sk_buff *rep;

	struct sock *sk;

	struct net *net;

	int err;



	net = sock_net(in_skb->sk);

	sk = raw_sock_get(net, r);

	if (IS_ERR(sk))

		return PTR_ERR(sk);
@@ -108,10 +109,7 @@ static int raw_diag_dump_one(struct sk_buff *in_skb, 
		return -ENOMEM;

	}



	err = inet_sk_diag_fill(sk, NULL, rep, r,

				sk_user_ns(NETLINK_CB(in_skb).sk),

				NETLINK_CB(in_skb).portid,

				nlh->nlmsg_seq, 0, nlh,

	err = inet_sk_diag_fill(sk, NULL, rep, cb, r, 0,

				netlink_net_capable(in_skb, CAP_NET_ADMIN));

	sock_put(sk);
@@ -136,11 +134,7 @@ static int sk_diag_dump(struct sock *sk, struct sk_buff *skb, 
	if (!inet_diag_bc_sk(bc, sk))

		return 0;



	return inet_sk_diag_fill(sk, NULL, skb, r,

				 sk_user_ns(NETLINK_CB(cb->skb).sk),

				 NETLINK_CB(cb->skb).portid,

				 cb->nlh->nlmsg_seq, NLM_F_MULTI,

				 cb->nlh, net_admin);

	return inet_sk_diag_fill(sk, NULL, skb, cb, r, NLM_F_MULTI, net_admin);

}



static void raw_diag_dump(struct sk_buff *skb, struct netlink_callback *cb,

net/ipv4/tcp_diag.c

+2 −2
Original line number Diff line number Diff line
@@ -184,10 +184,10 @@ static void tcp_diag_dump(struct sk_buff *skb, struct netlink_callback *cb, 
	inet_diag_dump_icsk(&tcp_hashinfo, skb, cb, r, bc);

}



static int tcp_diag_dump_one(struct sk_buff *in_skb, const struct nlmsghdr *nlh,

static int tcp_diag_dump_one(struct netlink_callback *cb,

			     const struct inet_diag_req_v2 *req)

{

	return inet_diag_dump_one_icsk(&tcp_hashinfo, in_skb, nlh, req);

	return inet_diag_dump_one_icsk(&tcp_hashinfo, cb, req);

}



#ifdef CONFIG_INET_DIAG_DESTROY

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