Patch "tcp: mark skbs with SCM_TIMESTAMPING_OPT_STATS" has been added to the 4.10-stable tree

[<gregkh@linuxfoundation.org>]

This is a note to let you know that I've just added the patch titled

    tcp: mark skbs with SCM_TIMESTAMPING_OPT_STATS

to the 4.10-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     tcp-mark-skbs-with-scm_timestamping_opt_stats.patch
and it can be found in the queue-4.10 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From foo@baz Sat Apr 29 08:22:40 CEST 2017
From: Soheil Hassas Yeganeh <soheil@google.com>
Date: Sat, 18 Mar 2017 17:03:00 -0400
Subject: tcp: mark skbs with SCM_TIMESTAMPING_OPT_STATS

From: Soheil Hassas Yeganeh <soheil@google.com>


[ Upstream commit 4ef1b2869447411ad3ef91ad7d4891a83c1a509a ]

SOF_TIMESTAMPING_OPT_STATS can be enabled and disabled
while packets are collected on the error queue.
So, checking SOF_TIMESTAMPING_OPT_STATS in sk->sk_tsflags
is not enough to safely assume that the skb contains
OPT_STATS data.

Add a bit in sock_exterr_skb to indicate whether the
skb contains opt_stats data.

Fixes: 1c885808e456 ("tcp: SOF_TIMESTAMPING_OPT_STATS option for SO_TIMESTAMPING")
Reported-by: JongHwan Kim <zzoru007@gmail.com>
Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 include/linux/errqueue.h |    2 ++
 net/core/skbuff.c        |   17 +++++++++++------
 net/socket.c             |    2 +-
 3 files changed, 14 insertions(+), 7 deletions(-)

--- a/include/linux/errqueue.h
+++ b/include/linux/errqueue.h
@@ -20,6 +20,8 @@ struct sock_exterr_skb {
 	struct sock_extended_err	ee;
 	u16				addr_offset;
 	__be16				port;
+	u8				opt_stats:1,
+					unused:7;
 };
 
 #endif
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -3799,16 +3799,20 @@ EXPORT_SYMBOL(skb_clone_sk);
 
 static void __skb_complete_tx_timestamp(struct sk_buff *skb,
 					struct sock *sk,
-					int tstype)
+					int tstype,
+					bool opt_stats)
 {
 	struct sock_exterr_skb *serr;
 	int err;
 
+	BUILD_BUG_ON(sizeof(struct sock_exterr_skb) > sizeof(skb->cb));
+
 	serr = SKB_EXT_ERR(skb);
 	memset(serr, 0, sizeof(*serr));
 	serr->ee.ee_errno = ENOMSG;
 	serr->ee.ee_origin = SO_EE_ORIGIN_TIMESTAMPING;
 	serr->ee.ee_info = tstype;
+	serr->opt_stats = opt_stats;
 	serr->header.h4.iif = skb->dev ? skb->dev->ifindex : 0;
 	if (sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID) {
 		serr->ee.ee_data = skb_shinfo(skb)->tskey;
@@ -3850,7 +3854,7 @@ void skb_complete_tx_timestamp(struct sk
 	 */
 	if (likely(atomic_inc_not_zero(&sk->sk_refcnt))) {
 		*skb_hwtstamps(skb) = *hwtstamps;
-		__skb_complete_tx_timestamp(skb, sk, SCM_TSTAMP_SND);
+		__skb_complete_tx_timestamp(skb, sk, SCM_TSTAMP_SND, false);
 		sock_put(sk);
 	}
 }
@@ -3861,7 +3865,7 @@ void __skb_tstamp_tx(struct sk_buff *ori
 		     struct sock *sk, int tstype)
 {
 	struct sk_buff *skb;
-	bool tsonly;
+	bool tsonly, opt_stats = false;
 
 	if (!sk)
 		return;
@@ -3874,9 +3878,10 @@ void __skb_tstamp_tx(struct sk_buff *ori
 #ifdef CONFIG_INET
 		if ((sk->sk_tsflags & SOF_TIMESTAMPING_OPT_STATS) &&
 		    sk->sk_protocol == IPPROTO_TCP &&
-		    sk->sk_type == SOCK_STREAM)
+		    sk->sk_type == SOCK_STREAM) {
 			skb = tcp_get_timestamping_opt_stats(sk);
-		else
+			opt_stats = true;
+		} else
 #endif
 			skb = alloc_skb(0, GFP_ATOMIC);
 	} else {
@@ -3895,7 +3900,7 @@ void __skb_tstamp_tx(struct sk_buff *ori
 	else
 		skb->tstamp = ktime_get_real();
 
-	__skb_complete_tx_timestamp(skb, sk, tstype);
+	__skb_complete_tx_timestamp(skb, sk, tstype, opt_stats);
 }
 EXPORT_SYMBOL_GPL(__skb_tstamp_tx);
 
--- a/net/socket.c
+++ b/net/socket.c
@@ -708,7 +708,7 @@ void __sock_recv_timestamp(struct msghdr
 			 SCM_TIMESTAMPING, sizeof(tss), &tss);
 
 		if (skb_is_err_queue(skb) && skb->len &&
-		    (sk->sk_tsflags & SOF_TIMESTAMPING_OPT_STATS))
+		    SKB_EXT_ERR(skb)->opt_stats)
 			put_cmsg(msg, SOL_SOCKET, SCM_TIMESTAMPING_OPT_STATS,
 				 skb->len, skb->data);
 	}


Patches currently in stable-queue which might be from soheil@google.com are

queue-4.10/tcp-mark-skbs-with-scm_timestamping_opt_stats.patch
queue-4.10/secure_seq-downgrade-to-per-host-timestamp-offsets.patch
queue-4.10/tcp-fix-scm_timestamping_opt_stats-for-normal-skbs.patch