package/libvncserver: fix CVE-2020-29260

libvncclient v0.9.13 was discovered to contain a memory leak via the
function rfbClientCleanup().

Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
(cherry picked from commit b3ab978703e0597b4bdf17d3e32cf0357db8315c)
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

package/libvncserver/0002-libvncclient-free-vncRec-memory-in-rfbClientCleanup.patch

@@ -0,0 +1,28 @@
+From bef41f6ec4097a8ee094f90a1b34a708fbd757ec Mon Sep 17 00:00:00 2001
+From: Christian Beier <info@christianbeier.net>
+Date: Sat, 21 Nov 2020 12:52:31 +0100
+Subject: [PATCH] libvncclient: free vncRec memory in rfbClientCleanup()
+
+Otherwise we leak memory. Spotted by Ramin Farajpour Cami
+<ramin.blackhat@gmail.com>, thanks!
+
+[Retrieved from:
+https://github.com/LibVNC/libvncserver/commit/bef41f6ec4097a8ee094f90a1b34a708fbd757ec]
+Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
+---
+ libvncclient/vncviewer.c | 2 ++
+ 1 file changed, 2 insertions(+)
+
+diff --git a/libvncclient/vncviewer.c b/libvncclient/vncviewer.c
+index d6b91f02b..0a1bdcf6a 100644
+--- a/libvncclient/vncviewer.c
++++ b/libvncclient/vncviewer.c
+@@ -534,6 +534,8 @@ void rfbClientCleanup(rfbClient* client) {
+     client->clientData = next;
+   }
+ 
++  free(client->vncRec);
++
+   if (client->sock != RFB_INVALID_SOCKET)
+     rfbCloseSocket(client->sock);
+   if (client->listenSock != RFB_INVALID_SOCKET)

package/libvncserver/libvncserver.mk

@@ -14,6 +14,9 @@ LIBVNCSERVER_INSTALL_STAGING = YES
 LIBVNCSERVER_DEPENDENCIES = host-pkgconf lzo
 LIBVNCSERVER_CONF_OPTS = -DWITH_LZO=ON
 
+# 0002-libvncclient-free-vncRec-memory-in-rfbClientCleanup.patch
+LIBVNCSERVER_IGNORE_CVES += CVE-2020-29260
+
 # only used for examples
 LIBVNCSERVER_CONF_OPTS += \
 	-DWITH_FFMPEG=OFF \