netdev - [PATCHv2 RFC net-next 4/7] tcp: replace dst_confirm with sk_dst

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Sat, 28 Jan 2017 16:26:15 +0200
From:   Julian Anastasov <ja@....bg>
To:     netdev@...r.kernel.org
Cc:     linux-sctp@...r.kernel.org, YueHaibing <yuehaibing@...wei.com>
Subject: [PATCHv2 RFC net-next 4/7] tcp: replace dst_confirm with sk_dst_confirm

When same struct dst_entry can be used for many different
neighbours we can not use it for pending confirmations.
Use the new sk_dst_confirm() helper to propagate the
indication from received packets to sock_confirm_neigh().

Reported-by: YueHaibing <yuehaibing@...wei.com>
Fixes: 5110effee8fd ("net: Do delayed neigh confirmation.")
Fixes: f2bb4bedf35d ("ipv4: Cache output routes in fib_info nexthops.")
Signed-off-by: Julian Anastasov <ja@....bg>
---
 net/ipv4/tcp_input.c   | 12 +++---------
 net/ipv4/tcp_metrics.c |  7 ++-----
 net/ipv4/tcp_output.c  |  2 ++
 3 files changed, 7 insertions(+), 14 deletions(-)

diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index 3de6eba..b3e88bb 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -3644,11 +3644,8 @@ static int tcp_ack(struct sock *sk, const struct sk_buff *skb, int flag)
 	if (tp->tlp_high_seq)
 		tcp_process_tlp_ack(sk, ack, flag);
 
-	if ((flag & FLAG_FORWARD_PROGRESS) || !(flag & FLAG_NOT_DUP)) {
-		struct dst_entry *dst = __sk_dst_get(sk);
-		if (dst)
-			dst_confirm(dst);
-	}
+	if ((flag & FLAG_FORWARD_PROGRESS) || !(flag & FLAG_NOT_DUP))
+		sk_dst_confirm(sk);
 
 	if (icsk->icsk_pending == ICSK_TIME_RETRANS)
 		tcp_schedule_loss_probe(sk);
@@ -5995,7 +5992,6 @@ int tcp_rcv_state_process(struct sock *sk, struct sk_buff *skb)
 		break;
 
 	case TCP_FIN_WAIT1: {
-		struct dst_entry *dst;
 		int tmo;
 
 		/* If we enter the TCP_FIN_WAIT1 state and we are a
@@ -6022,9 +6018,7 @@ int tcp_rcv_state_process(struct sock *sk, struct sk_buff *skb)
 		tcp_set_state(sk, TCP_FIN_WAIT2);
 		sk->sk_shutdown |= SEND_SHUTDOWN;
 
-		dst = __sk_dst_get(sk);
-		if (dst)
-			dst_confirm(dst);
+		sk_dst_confirm(sk);
 
 		if (!sock_flag(sk, SOCK_DEAD)) {
 			/* Wake up lingering close() */
diff --git a/net/ipv4/tcp_metrics.c b/net/ipv4/tcp_metrics.c
index b9ed0d5..0f46e5f 100644
--- a/net/ipv4/tcp_metrics.c
+++ b/net/ipv4/tcp_metrics.c
@@ -375,12 +375,10 @@ void tcp_update_metrics(struct sock *sk)
 	u32 val;
 	int m;
 
+	sk_dst_confirm(sk);
 	if (sysctl_tcp_nometrics_save || !dst)
 		return;
 
-	if (dst->flags & DST_HOST)
-		dst_confirm(dst);
-
 	rcu_read_lock();
 	if (icsk->icsk_backoff || !tp->srtt_us) {
 		/* This session failed to estimate rtt. Why?
@@ -493,11 +491,10 @@ void tcp_init_metrics(struct sock *sk)
 	struct tcp_metrics_block *tm;
 	u32 val, crtt = 0; /* cached RTT scaled by 8 */
 
+	sk_dst_confirm(sk);
 	if (!dst)
 		goto reset;
 
-	dst_confirm(dst);
-
 	rcu_read_lock();
 	tm = tcp_get_metrics(sk, dst, true);
 	if (!tm) {
diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
index 671c695..c1f8a59 100644
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -973,6 +973,8 @@ static int tcp_transmit_skb(struct sock *sk, struct sk_buff *skb, int clone_it,
 	skb_set_hash_from_sk(skb, sk);
 	atomic_add(skb->truesize, &sk->sk_wmem_alloc);
 
+	skb_set_dst_pending_confirm(skb, sk->sk_dst_pending_confirm);
+
 	/* Build TCP header and checksum it. */
 	th = (struct tcphdr *)skb->data;
 	th->source		= inet->inet_sport;
-- 
1.9.3