openssh: fix CVE-2016-8858

Backport patch to fix CVE-2016-8858 of openssh.

Ref:
https://bugzilla.redhat.com/show_bug.cgi?id=1384860

(From OE-Core rev: 134a05616839d002970b2e7124ea38348d10209b)

Signed-off-by: Kai Kang <kai.kang@windriver.com>
Signed-off-by: Ross Burton <ross.burton@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/recipes-connectivity/openssh/openssh/fix-CVE-2016-8858.patch

@@ -0,0 +1,39 @@
+Fix CVE-2016-8858 of openssh
+
+Backport patch from upstream and drop the change of comment which can NOT be applied.
+
+Upstream-Status: Backport [ https://anongit.mindrot.org/openssh.git/commit/?id=ec165c3 ]
+CVE: CVE-2016-8858
+
+Signed-off-by: Kai Kang <kai.kang@windriver.com>
+---
+From ec165c392ca54317dbe3064a8c200de6531e89ad Mon Sep 17 00:00:00 2001
+From: "markus@openbsd.org" <markus@openbsd.org>
+Date: Mon, 10 Oct 2016 19:28:48 +0000
+Subject: [PATCH] upstream commit
+
+Unregister the KEXINIT handler after message has been
+received. Otherwise an unauthenticated peer can repeat the KEXINIT and cause
+allocation of up to 128MB -- until the connection is closed. Reported by
+shilei-c at 360.cn
+
+Upstream-ID: 43649ae12a27ef94290db16d1a98294588b75c05
+---
+ kex.c | 3 ++-
+ 1 file changed, 2 insertions(+), 1 deletion(-)
+
+diff --git a/kex.c b/kex.c
+index 3f97f8c..6a94bc5 100644
+--- a/kex.c
++++ b/kex.c
+@@ -481,6 +481,7 @@ kex_input_kexinit(int type, u_int32_t seq, void *ctxt)
+ 	if (kex == NULL)
+ 		return SSH_ERR_INVALID_ARGUMENT;
+ 
++	ssh_dispatch_set(ssh, SSH2_MSG_KEXINIT, NULL);
+ 	ptr = sshpkt_ptr(ssh, &dlen);
+ 	if ((r = sshbuf_put(kex->peer, ptr, dlen)) != 0)
+ 		return r;
+-- 
+2.10.1
+

meta/recipes-connectivity/openssh/openssh_7.3p1.bb

@@ -25,6 +25,7 @@ SRC_URI = "http://ftp.openbsd.org/pub/OpenBSD/OpenSSH/portable/openssh-${PV}.tar
            file://openssh-7.1p1-conditional-compile-des-in-cipher.patch \
            file://openssh-7.1p1-conditional-compile-des-in-pkcs11.patch \
            file://fix-potential-signed-overflow-in-pointer-arithmatic.patch \
+           file://fix-CVE-2016-8858.patch \
            "
 
 PAM_SRC_URI = "file://sshd"