dnsmasq: CVE-2017-14492

Heap based overflow.

References:
https://cve.mitre.org/cgi-bin/cvename.cgi?name=2017-14492
https://security.googleblog.com/2017/10/behind-masq-yet-more-dns-and-dhcp.html

Signed-off-by: Sona Sarmadi <sona.sarmadi@enea.com>
Signed-off-by: Adrian Dudau <adrian.dudau@enea.com>

2 files changed, 58 insertions, 0 deletions

diff --git a/recipes-networking/dnsmasq/dnsmasq/CVE-2017-14492.patch b/recipes-networking/dnsmasq/dnsmasq/CVE-2017-14492.patch
new file mode 100644
index 0000000..5b66944
--- /dev/null
+++ b/recipes-networking/dnsmasq/dnsmasq/CVE-2017-14492.patch
@@ -0,0 +1,57 @@
+From 24036ea507862c7b7898b68289c8130f85599c10 Mon Sep 17 00:00:00 2001
+From: Simon Kelley <simon@thekelleys.org.uk>
+Date: Mon, 25 Sep 2017 18:47:15 +0100
+Subject: [PATCH] Security fix, CVE-2017-14492, DHCPv6 RA heap overflow.
+
+Fix heap overflow in IPv6 router advertisement code.
+This is a potentially serious security hole, as a
+crafted RA request can overflow a buffer and crash or
+control dnsmasq. Attacker must be on the local network.
+
+CVE: CVE-2017-14492
+Upstream-Status: Backport
+
+Signed-off-by: Sona Sarmadi <sona.sarmadi@enea.com>
+---
+ CHANGELOG  |   10 +++++++++-
+ src/radv.c |    3 +++
+ 2 files changed, 12 insertions(+), 1 deletion(-)
+
+diff --git a/CHANGELOG b/CHANGELOG
+index a7c2f35..df6c157 100644
+--- a/CHANGELOG
++++ b/CHANGELOG
+@@ -35,7 +35,15 @@ version 2.78
+        and Kevin Hamacher of the Google Security Team for
+        finding this.
+ 
+-
++       Fix heap overflow in IPv6 router advertisement code.
++       This is a potentially serious security hole, as a
++       crafted RA request can overflow a buffer and crash or
++       control dnsmasq. Attacker must be on the local network.
++       CVE-2017-14492 applies.
++        Credit to Felix Wilhelm, Fermin J. Serna, Gabriel Campana
++       and Kevin Hamacher of the Google Security Team for
++       finding this.
++       
+        
+ version 2.77
+        Generate an error when configured with a CNAME loop,
+diff --git a/src/radv.c b/src/radv.c
+index 1032189..9b7e52c 100644
+--- a/src/radv.c
++++ b/src/radv.c
+@@ -198,6 +198,9 @@ void icmp6_packet(time_t now)
+       /* look for link-layer address option for logging */
+       if (sz >= 16 && packet[8] == ICMP6_OPT_SOURCE_MAC && (packet[9] * 8) + 8 <= sz)
+        {
++         if ((packet[9] * 8 - 2) * 3 - 1 >= MAXDNAME) {
++           return;
++         }
+          print_mac(daemon->namebuff, &packet[10], (packet[9] * 8) - 2);
+          mac = daemon->namebuff;
+        }
+-- 
+1.7.10.4
+
diff --git a/recipes-networking/dnsmasq/dnsmasq_%.bbappend b/recipes-networking/dnsmasq/dnsmasq_%.bbappend
index e228035..1fc8819 100644
--- a/recipes-networking/dnsmasq/dnsmasq_%.bbappend
+++ b/recipes-networking/dnsmasq/dnsmasq_%.bbappend
@@ -3,4 +3,5 @@ FILESEXTRAPATHS_prepend := "${THISDIR}/${PN}:"
 
 SRC_URI += "file://0001-CVE-2017-14491.patch \
     file://0002-CVE-2017-14491.patch \
+    file://CVE-2017-14492.patch \
 "