Patch "ipv6: make sure to initialize sockc.tsflags before first use" has been added to the 4.9-stable tree

[<gregkh@linuxfoundation.org>]

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

    ipv6: make sure to initialize sockc.tsflags before first use

to the 4.9-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:
     ipv6-make-sure-to-initialize-sockc.tsflags-before-first-use.patch
and it can be found in the queue-4.9 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 Mon Mar 27 18:17:54 CEST 2017
From: Alexander Potapenko <glider@google.com>
Date: Tue, 21 Mar 2017 17:14:27 +0100
Subject: ipv6: make sure to initialize sockc.tsflags before first use

From: Alexander Potapenko <glider@google.com>


[ Upstream commit d515684d78148884d5fc425ba904c50f03844020 ]

In the case udp_sk(sk)->pending is AF_INET6, udpv6_sendmsg() would
jump to do_append_data, skipping the initialization of sockc.tsflags.
Fix the problem by moving sockc.tsflags initialization earlier.

The bug was detected with KMSAN.

Fixes: c14ac9451c34 ("sock: enable timestamping using control messages")
Signed-off-by: Alexander Potapenko <glider@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 net/ipv6/udp.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/net/ipv6/udp.c
+++ b/net/ipv6/udp.c
@@ -1037,6 +1037,7 @@ int udpv6_sendmsg(struct sock *sk, struc
 	ipc6.hlimit = -1;
 	ipc6.tclass = -1;
 	ipc6.dontfrag = -1;
+	sockc.tsflags = sk->sk_tsflags;
 
 	/* destination address check */
 	if (sin6) {
@@ -1156,7 +1157,6 @@ do_udp_sendmsg:
 		fl6.flowi6_oif = np->sticky_pktinfo.ipi6_ifindex;
 
 	fl6.flowi6_mark = sk->sk_mark;
-	sockc.tsflags = sk->sk_tsflags;
 
 	if (msg->msg_controllen) {
 		opt = &opt_space;


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

queue-4.9/ipv4-provide-stronger-user-input-validation-in-nl_fib_input.patch
queue-4.9/ipv6-make-sure-to-initialize-sockc.tsflags-before-first-use.patch