1 files changed, 324 insertions, 87 deletions

diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index a692626c19e4..2e62e0d6373a 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -2277,51 +2277,72 @@ EXPORT_SYMBOL(tcp_v4_destroy_sock);
 #ifdef CONFIG_PROC_FS
 /* Proc filesystem TCP sock list dumping. */
 
-/*
- * Get next listener socket follow cur.  If cur is NULL, get first socket
- * starting from bucket given in st->bucket; when st->bucket is zero the
- * very first socket in the hash table is returned.
+static unsigned short seq_file_family(const struct seq_file *seq);
+
+static bool seq_sk_match(struct seq_file *seq, const struct sock *sk)
+{
+	unsigned short family = seq_file_family(seq);
+
+	/* AF_UNSPEC is used as a match all */
+	return ((family == AF_UNSPEC || family == sk->sk_family) &&
+		net_eq(sock_net(sk), seq_file_net(seq)));
+}
+
+/* Find a non empty bucket (starting from st->bucket)
+ * and return the first sk from it.
  */
-static void *listening_get_next(struct seq_file *seq, void *cur)
+static void *listening_get_first(struct seq_file *seq)
 {
-	struct tcp_seq_afinfo *afinfo;
 	struct tcp_iter_state *st = seq->private;
-	struct net *net = seq_file_net(seq);
-	struct inet_listen_hashbucket *ilb;
-	struct hlist_nulls_node *node;
-	struct sock *sk = cur;
 
-	if (st->bpf_seq_afinfo)
-		afinfo = st->bpf_seq_afinfo;
-	else
-		afinfo = PDE_DATA(file_inode(seq->file));
+	st->offset = 0;
+	for (; st->bucket <= tcp_hashinfo.lhash2_mask; st->bucket++) {
+		struct inet_listen_hashbucket *ilb2;
+		struct inet_connection_sock *icsk;
+		struct sock *sk;
 
-	if (!sk) {
-get_head:
-		ilb = &tcp_hashinfo.listening_hash[st->bucket];
-		spin_lock(&ilb->lock);
-		sk = sk_nulls_head(&ilb->nulls_head);
-		st->offset = 0;
-		goto get_sk;
+		ilb2 = &tcp_hashinfo.lhash2[st->bucket];
+		if (hlist_empty(&ilb2->head))
+			continue;
+
+		spin_lock(&ilb2->lock);
+		inet_lhash2_for_each_icsk(icsk, &ilb2->head) {
+			sk = (struct sock *)icsk;
+			if (seq_sk_match(seq, sk))
+				return sk;
+		}
+		spin_unlock(&ilb2->lock);
 	}
-	ilb = &tcp_hashinfo.listening_hash[st->bucket];
+
+	return NULL;
+}
+
+/* Find the next sk of "cur" within the same bucket (i.e. st->bucket).
+ * If "cur" is the last one in the st->bucket,
+ * call listening_get_first() to return the first sk of the next
+ * non empty bucket.
+ */
+static void *listening_get_next(struct seq_file *seq, void *cur)
+{
+	struct tcp_iter_state *st = seq->private;
+	struct inet_listen_hashbucket *ilb2;
+	struct inet_connection_sock *icsk;
+	struct sock *sk = cur;
+
 	++st->num;
 	++st->offset;
 
-	sk = sk_nulls_next(sk);
-get_sk:
-	sk_nulls_for_each_from(sk, node) {
-		if (!net_eq(sock_net(sk), net))
-			continue;
-		if (afinfo->family == AF_UNSPEC ||
-		    sk->sk_family == afinfo->family)
+	icsk = inet_csk(sk);
+	inet_lhash2_for_each_icsk_continue(icsk) {
+		sk = (struct sock *)icsk;
+		if (seq_sk_match(seq, sk))
 			return sk;
 	}
-	spin_unlock(&ilb->lock);
-	st->offset = 0;
-	if (++st->bucket < INET_LHTABLE_SIZE)
-		goto get_head;
-	return NULL;
+
+	ilb2 = &tcp_hashinfo.lhash2[st->bucket];
+	spin_unlock(&ilb2->lock);
+	++st->bucket;
+	return listening_get_first(seq);
 }
 
 static void *listening_get_idx(struct seq_file *seq, loff_t *pos)
@@ -2331,7 +2352,7 @@ static void *listening_get_idx(struct seq_file *seq, loff_t *pos)
 
 	st->bucket = 0;
 	st->offset = 0;
-	rc = listening_get_next(seq, NULL);
+	rc = listening_get_first(seq);
 
 	while (rc && *pos) {
 		rc = listening_get_next(seq, rc);
@@ -2351,15 +2372,7 @@ static inline bool empty_bucket(const struct tcp_iter_state *st)
  */
 static void *established_get_first(struct seq_file *seq)
 {
-	struct tcp_seq_afinfo *afinfo;
 	struct tcp_iter_state *st = seq->private;
-	struct net *net = seq_file_net(seq);
-	void *rc = NULL;
-
-	if (st->bpf_seq_afinfo)
-		afinfo = st->bpf_seq_afinfo;
-	else
-		afinfo = PDE_DATA(file_inode(seq->file));
 
 	st->offset = 0;
 	for (; st->bucket <= tcp_hashinfo.ehash_mask; ++st->bucket) {
@@ -2373,32 +2386,20 @@ static void *established_get_first(struct seq_file *seq)
 
 		spin_lock_bh(lock);
 		sk_nulls_for_each(sk, node, &tcp_hashinfo.ehash[st->bucket].chain) {
-			if ((afinfo->family != AF_UNSPEC &&
-			     sk->sk_family != afinfo->family) ||
-			    !net_eq(sock_net(sk), net)) {
-				continue;
-			}
-			rc = sk;
-			goto out;
+			if (seq_sk_match(seq, sk))
+				return sk;
 		}
 		spin_unlock_bh(lock);
 	}
-out:
-	return rc;
+
+	return NULL;
 }
 
 static void *established_get_next(struct seq_file *seq, void *cur)
 {
-	struct tcp_seq_afinfo *afinfo;
 	struct sock *sk = cur;
 	struct hlist_nulls_node *node;
 	struct tcp_iter_state *st = seq->private;
-	struct net *net = seq_file_net(seq);
-
-	if (st->bpf_seq_afinfo)
-		afinfo = st->bpf_seq_afinfo;
-	else
-		afinfo = PDE_DATA(file_inode(seq->file));
 
 	++st->num;
 	++st->offset;
@@ -2406,9 +2407,7 @@ static void *established_get_next(struct seq_file *seq, void *cur)
 	sk = sk_nulls_next(sk);
 
 	sk_nulls_for_each_from(sk, node) {
-		if ((afinfo->family == AF_UNSPEC ||
-		     sk->sk_family == afinfo->family) &&
-		    net_eq(sock_net(sk), net))
+		if (seq_sk_match(seq, sk))
 			return sk;
 	}
 
@@ -2451,17 +2450,18 @@ static void *tcp_get_idx(struct seq_file *seq, loff_t pos)
 static void *tcp_seek_last_pos(struct seq_file *seq)
 {
 	struct tcp_iter_state *st = seq->private;
+	int bucket = st->bucket;
 	int offset = st->offset;
 	int orig_num = st->num;
 	void *rc = NULL;
 
 	switch (st->state) {
 	case TCP_SEQ_STATE_LISTENING:
-		if (st->bucket >= INET_LHTABLE_SIZE)
+		if (st->bucket > tcp_hashinfo.lhash2_mask)
 			break;
 		st->state = TCP_SEQ_STATE_LISTENING;
-		rc = listening_get_next(seq, NULL);
-		while (offset-- && rc)
+		rc = listening_get_first(seq);
+		while (offset-- && rc && bucket == st->bucket)
 			rc = listening_get_next(seq, rc);
 		if (rc)
 			break;
@@ -2472,7 +2472,7 @@ static void *tcp_seek_last_pos(struct seq_file *seq)
 		if (st->bucket > tcp_hashinfo.ehash_mask)
 			break;
 		rc = established_get_first(seq);
-		while (offset-- && rc)
+		while (offset-- && rc && bucket == st->bucket)
 			rc = established_get_next(seq, rc);
 	}
 
@@ -2542,7 +2542,7 @@ void tcp_seq_stop(struct seq_file *seq, void *v)
 	switch (st->state) {
 	case TCP_SEQ_STATE_LISTENING:
 		if (v != SEQ_START_TOKEN)
-			spin_unlock(&tcp_hashinfo.listening_hash[st->bucket].lock);
+			spin_unlock(&tcp_hashinfo.lhash2[st->bucket].lock);
 		break;
 	case TCP_SEQ_STATE_ESTABLISHED:
 		if (v)
@@ -2687,6 +2687,15 @@ out:
 }
 
 #ifdef CONFIG_BPF_SYSCALL
+struct bpf_tcp_iter_state {
+	struct tcp_iter_state state;
+	unsigned int cur_sk;
+	unsigned int end_sk;
+	unsigned int max_sk;
+	struct sock **batch;
+	bool st_bucket_done;
+};
+
 struct bpf_iter__tcp {
 	__bpf_md_ptr(struct bpf_iter_meta *, meta);
 	__bpf_md_ptr(struct sock_common *, sk_common);
@@ -2705,16 +2714,204 @@ static int tcp_prog_seq_show(struct bpf_prog *prog, struct bpf_iter_meta *meta,
 	return bpf_iter_run_prog(prog, &ctx);
 }
 
+static void bpf_iter_tcp_put_batch(struct bpf_tcp_iter_state *iter)
+{
+	while (iter->cur_sk < iter->end_sk)
+		sock_put(iter->batch[iter->cur_sk++]);
+}
+
+static int bpf_iter_tcp_realloc_batch(struct bpf_tcp_iter_state *iter,
+				      unsigned int new_batch_sz)
+{
+	struct sock **new_batch;
+
+	new_batch = kvmalloc(sizeof(*new_batch) * new_batch_sz,
+			     GFP_USER | __GFP_NOWARN);
+	if (!new_batch)
+		return -ENOMEM;
+
+	bpf_iter_tcp_put_batch(iter);
+	kvfree(iter->batch);
+	iter->batch = new_batch;
+	iter->max_sk = new_batch_sz;
+
+	return 0;
+}
+
+static unsigned int bpf_iter_tcp_listening_batch(struct seq_file *seq,
+						 struct sock *start_sk)
+{
+	struct bpf_tcp_iter_state *iter = seq->private;
+	struct tcp_iter_state *st = &iter->state;
+	struct inet_connection_sock *icsk;
+	unsigned int expected = 1;
+	struct sock *sk;
+
+	sock_hold(start_sk);
+	iter->batch[iter->end_sk++] = start_sk;
+
+	icsk = inet_csk(start_sk);
+	inet_lhash2_for_each_icsk_continue(icsk) {
+		sk = (struct sock *)icsk;
+		if (seq_sk_match(seq, sk)) {
+			if (iter->end_sk < iter->max_sk) {
+				sock_hold(sk);
+				iter->batch[iter->end_sk++] = sk;
+			}
+			expected++;
+		}
+	}
+	spin_unlock(&tcp_hashinfo.lhash2[st->bucket].lock);
+
+	return expected;
+}
+
+static unsigned int bpf_iter_tcp_established_batch(struct seq_file *seq,
+						   struct sock *start_sk)
+{
+	struct bpf_tcp_iter_state *iter = seq->private;
+	struct tcp_iter_state *st = &iter->state;
+	struct hlist_nulls_node *node;
+	unsigned int expected = 1;
+	struct sock *sk;
+
+	sock_hold(start_sk);
+	iter->batch[iter->end_sk++] = start_sk;
+
+	sk = sk_nulls_next(start_sk);
+	sk_nulls_for_each_from(sk, node) {
+		if (seq_sk_match(seq, sk)) {
+			if (iter->end_sk < iter->max_sk) {
+				sock_hold(sk);
+				iter->batch[iter->end_sk++] = sk;
+			}
+			expected++;
+		}
+	}
+	spin_unlock_bh(inet_ehash_lockp(&tcp_hashinfo, st->bucket));
+
+	return expected;
+}
+
+static struct sock *bpf_iter_tcp_batch(struct seq_file *seq)
+{
+	struct bpf_tcp_iter_state *iter = seq->private;
+	struct tcp_iter_state *st = &iter->state;
+	unsigned int expected;
+	bool resized = false;
+	struct sock *sk;
+
+	/* The st->bucket is done.  Directly advance to the next
+	 * bucket instead of having the tcp_seek_last_pos() to skip
+	 * one by one in the current bucket and eventually find out
+	 * it has to advance to the next bucket.
+	 */
+	if (iter->st_bucket_done) {
+		st->offset = 0;
+		st->bucket++;
+		if (st->state == TCP_SEQ_STATE_LISTENING &&
+		    st->bucket > tcp_hashinfo.lhash2_mask) {
+			st->state = TCP_SEQ_STATE_ESTABLISHED;
+			st->bucket = 0;
+		}
+	}
+
+again:
+	/* Get a new batch */
+	iter->cur_sk = 0;
+	iter->end_sk = 0;
+	iter->st_bucket_done = false;
+
+	sk = tcp_seek_last_pos(seq);
+	if (!sk)
+		return NULL; /* Done */
+
+	if (st->state == TCP_SEQ_STATE_LISTENING)
+		expected = bpf_iter_tcp_listening_batch(seq, sk);
+	else
+		expected = bpf_iter_tcp_established_batch(seq, sk);
+
+	if (iter->end_sk == expected) {
+		iter->st_bucket_done = true;
+		return sk;
+	}
+
+	if (!resized && !bpf_iter_tcp_realloc_batch(iter, expected * 3 / 2)) {
+		resized = true;
+		goto again;
+	}
+
+	return sk;
+}
+
+static void *bpf_iter_tcp_seq_start(struct seq_file *seq, loff_t *pos)
+{
+	/* bpf iter does not support lseek, so it always
+	 * continue from where it was stop()-ped.
+	 */
+	if (*pos)
+		return bpf_iter_tcp_batch(seq);
+
+	return SEQ_START_TOKEN;
+}
+
+static void *bpf_iter_tcp_seq_next(struct seq_file *seq, void *v, loff_t *pos)
+{
+	struct bpf_tcp_iter_state *iter = seq->private;
+	struct tcp_iter_state *st = &iter->state;
+	struct sock *sk;
+
+	/* Whenever seq_next() is called, the iter->cur_sk is
+	 * done with seq_show(), so advance to the next sk in
+	 * the batch.
+	 */
+	if (iter->cur_sk < iter->end_sk) {
+		/* Keeping st->num consistent in tcp_iter_state.
+		 * bpf_iter_tcp does not use st->num.
+		 * meta.seq_num is used instead.
+		 */
+		st->num++;
+		/* Move st->offset to the next sk in the bucket such that
+		 * the future start() will resume at st->offset in
+		 * st->bucket.  See tcp_seek_last_pos().
+		 */
+		st->offset++;
+		sock_put(iter->batch[iter->cur_sk++]);
+	}
+
+	if (iter->cur_sk < iter->end_sk)
+		sk = iter->batch[iter->cur_sk];
+	else
+		sk = bpf_iter_tcp_batch(seq);
+
+	++*pos;
+	/* Keeping st->last_pos consistent in tcp_iter_state.
+	 * bpf iter does not do lseek, so st->last_pos always equals to *pos.
+	 */
+	st->last_pos = *pos;
+	return sk;
+}
+
 static int bpf_iter_tcp_seq_show(struct seq_file *seq, void *v)
 {
 	struct bpf_iter_meta meta;
 	struct bpf_prog *prog;
 	struct sock *sk = v;
+	bool slow;
 	uid_t uid;
+	int ret;
 
 	if (v == SEQ_START_TOKEN)
 		return 0;
 
+	if (sk_fullsock(sk))
+		slow = lock_sock_fast(sk);
+
+	if (unlikely(sk_unhashed(sk))) {
+		ret = SEQ_SKIP;
+		goto unlock;
+	}
+
 	if (sk->sk_state == TCP_TIME_WAIT) {
 		uid = 0;
 	} else if (sk->sk_state == TCP_NEW_SYN_RECV) {
@@ -2728,11 +2925,18 @@ static int bpf_iter_tcp_seq_show(struct seq_file *seq, void *v)
 
 	meta.seq = seq;
 	prog = bpf_iter_get_info(&meta, false);
-	return tcp_prog_seq_show(prog, &meta, v, uid);
+	ret = tcp_prog_seq_show(prog, &meta, v, uid);
+
+unlock:
+	if (sk_fullsock(sk))
+		unlock_sock_fast(sk, slow);
+	return ret;
+
 }
 
 static void bpf_iter_tcp_seq_stop(struct seq_file *seq, void *v)
 {
+	struct bpf_tcp_iter_state *iter = seq->private;
 	struct bpf_iter_meta meta;
 	struct bpf_prog *prog;
 
@@ -2743,16 +2947,33 @@ static void bpf_iter_tcp_seq_stop(struct seq_file *seq, void *v)
 			(void)tcp_prog_seq_show(prog, &meta, v, 0);
 	}
 
-	tcp_seq_stop(seq, v);
+	if (iter->cur_sk < iter->end_sk) {
+		bpf_iter_tcp_put_batch(iter);
+		iter->st_bucket_done = false;
+	}
 }
 
 static const struct seq_operations bpf_iter_tcp_seq_ops = {
 	.show		= bpf_iter_tcp_seq_show,
-	.start		= tcp_seq_start,
-	.next		= tcp_seq_next,
+	.start		= bpf_iter_tcp_seq_start,
+	.next		= bpf_iter_tcp_seq_next,
 	.stop		= bpf_iter_tcp_seq_stop,
 };
 #endif
+static unsigned short seq_file_family(const struct seq_file *seq)
+{
+	const struct tcp_seq_afinfo *afinfo;
+
+#ifdef CONFIG_BPF_SYSCALL
+	/* Iterated from bpf_iter.  Let the bpf prog to filter instead. */
+	if (seq->op == &bpf_iter_tcp_seq_ops)
+		return AF_UNSPEC;
+#endif
+
+	/* Iterated from proc fs */
+	afinfo = PDE_DATA(file_inode(seq->file));
+	return afinfo->family;
+}
 
 static const struct seq_operations tcp4_seq_ops = {
 	.show		= tcp4_seq_show,
@@ -2964,7 +3185,6 @@ static int __net_init tcp_sk_init(struct net *net)
 	net->ipv4.sysctl_tcp_comp_sack_slack_ns = 100 * NSEC_PER_USEC;
 	net->ipv4.sysctl_tcp_comp_sack_nr = 44;
 	net->ipv4.sysctl_tcp_fastopen = TFO_CLIENT_ENABLE;
-	spin_lock_init(&net->ipv4.tcp_fastopen_ctx_lock);
 	net->ipv4.sysctl_tcp_fastopen_blackhole_timeout = 0;
 	atomic_set(&net->ipv4.tfo_active_disable_times, 0);
 
@@ -3003,39 +3223,55 @@ static struct pernet_operations __net_initdata tcp_sk_ops = {
 DEFINE_BPF_ITER_FUNC(tcp, struct bpf_iter_meta *meta,
 		     struct sock_common *sk_common, uid_t uid)
 
+#define INIT_BATCH_SZ 16
+
 static int bpf_iter_init_tcp(void *priv_data, struct bpf_iter_aux_info *aux)
 {
-	struct tcp_iter_state *st = priv_data;
-	struct tcp_seq_afinfo *afinfo;
-	int ret;
+	struct bpf_tcp_iter_state *iter = priv_data;
+	int err;
 
-	afinfo = kmalloc(sizeof(*afinfo), GFP_USER | __GFP_NOWARN);
-	if (!afinfo)
-		return -ENOMEM;
+	err = bpf_iter_init_seq_net(priv_data, aux);
+	if (err)
+		return err;
 
-	afinfo->family = AF_UNSPEC;
-	st->bpf_seq_afinfo = afinfo;
-	ret = bpf_iter_init_seq_net(priv_data, aux);
-	if (ret)
-		kfree(afinfo);
-	return ret;
+	err = bpf_iter_tcp_realloc_batch(iter, INIT_BATCH_SZ);
+	if (err) {
+		bpf_iter_fini_seq_net(priv_data);
+		return err;
+	}
+
+	return 0;
 }
 
 static void bpf_iter_fini_tcp(void *priv_data)
 {
-	struct tcp_iter_state *st = priv_data;
+	struct bpf_tcp_iter_state *iter = priv_data;
 
-	kfree(st->bpf_seq_afinfo);
 	bpf_iter_fini_seq_net(priv_data);
+	kvfree(iter->batch);
 }
 
 static const struct bpf_iter_seq_info tcp_seq_info = {
 	.seq_ops		= &bpf_iter_tcp_seq_ops,
 	.init_seq_private	= bpf_iter_init_tcp,
 	.fini_seq_private	= bpf_iter_fini_tcp,
-	.seq_priv_size		= sizeof(struct tcp_iter_state),
+	.seq_priv_size		= sizeof(struct bpf_tcp_iter_state),
 };
 
+static const struct bpf_func_proto *
+bpf_iter_tcp_get_func_proto(enum bpf_func_id func_id,
+			    const struct bpf_prog *prog)
+{
+	switch (func_id) {
+	case BPF_FUNC_setsockopt:
+		return &bpf_sk_setsockopt_proto;
+	case BPF_FUNC_getsockopt:
+		return &bpf_sk_getsockopt_proto;
+	default:
+		return NULL;
+	}
+}
+
 static struct bpf_iter_reg tcp_reg_info = {
 	.target			= "tcp",
 	.ctx_arg_info_size	= 1,
@@ -3043,6 +3279,7 @@ static struct bpf_iter_reg tcp_reg_info = {
 		{ offsetof(struct bpf_iter__tcp, sk_common),
 		  PTR_TO_BTF_ID_OR_NULL },
 	},
+	.get_func_proto		= bpf_iter_tcp_get_func_proto,
 	.seq_info		= &tcp_seq_info,
 };