From 331ebdd3de4437b493d0e4e12fa8b97fa976f5a4 Mon Sep 17 00:00:00 2001
From: Sebastian Pipping <sping@gentoo.org>
Date: Wed, 22 Jun 2016 22:12:30 +0200
Subject: media-gfx/gimp: CVE-2016-4994 (bug #586666)

Package-Manager: portage-2.2.28
---
 .../gimp/files/gimp-2.9.2-CVE-2016-4994.patch      | 88 ++++++++++++++++++++++
 1 file changed, 88 insertions(+)
 create mode 100644 media-gfx/gimp/files/gimp-2.9.2-CVE-2016-4994.patch

(limited to 'media-gfx/gimp/files/gimp-2.9.2-CVE-2016-4994.patch')

diff --git a/media-gfx/gimp/files/gimp-2.9.2-CVE-2016-4994.patch b/media-gfx/gimp/files/gimp-2.9.2-CVE-2016-4994.patch
new file mode 100644
index 000000000000..846318b42149
--- /dev/null
+++ b/media-gfx/gimp/files/gimp-2.9.2-CVE-2016-4994.patch
@@ -0,0 +1,88 @@
+From 6d804bf9ae77bc86a0a97f9b944a129844df9395 Mon Sep 17 00:00:00 2001
+From: Shmuel H <shmuelgimp@gmail.com>
+Date: Mon, 20 Jun 2016 17:14:41 +0300
+Subject: Bug 767873 - (CVE-2016-4994) Multiple Use-After-Free when parsing...
+
+...XCF channel and layer properties
+
+The properties PROP_ACTIVE_LAYER, PROP_FLOATING_SELECTION,
+PROP_ACTIVE_CHANNEL saves the current object pointer the @info
+structure. Others like PROP_SELECTION (for channel) and
+PROP_GROUP_ITEM (for layer) will delete the current object and create
+a new object, leaving the pointers in @info invalid (dangling).
+
+Therefore, if a property from the first type will come before the
+second, the result will be an UaF in the last lines of xcf_load_image
+(when it actually using the pointers from @info).
+
+I wasn't able to exploit this bug because that
+g_object_instance->c_class gets cleared by the last g_object_unref and
+GIMP_IS_{LAYER,CHANNEL} detects that and return FALSE.
+---
+ app/xcf/xcf-load.c | 29 +++++++++++++++++++++++++++++
+ 1 file changed, 29 insertions(+)
+
+diff --git a/app/xcf/xcf-load.c b/app/xcf/xcf-load.c
+index f48558a..244d5c2 100644
+--- a/app/xcf/xcf-load.c
++++ b/app/xcf/xcf-load.c
+@@ -1141,6 +1141,18 @@ xcf_load_layer_props (XcfInfo    *info,
+         case PROP_GROUP_ITEM:
+           {
+             GimpLayer *group;
++            gboolean   is_active_layer;
++
++            /* We're going to delete *layer, Don't leave its pointers
++             * in @info.  After that, we'll restore them back with the
++             * new pointer. See bug #767873.
++             */
++            is_active_layer = (*layer == info->active_layer);
++            if (is_active_layer)
++              info->active_layer = NULL;
++
++            if (*layer == info->floating_sel)
++              info->floating_sel = NULL;
+ 
+             group = gimp_group_layer_new (image);
+ 
+@@ -1150,6 +1162,13 @@ xcf_load_layer_props (XcfInfo    *info,
+             g_object_ref_sink (*layer);
+             g_object_unref (*layer);
+             *layer = group;
++
++            if (is_active_layer)
++              info->active_layer = *layer;
++
++            /* Don't restore info->floating_sel because group layers
++             * can't be floating selections
++             */
+           }
+           break;
+ 
+@@ -1220,6 +1239,12 @@ xcf_load_channel_props (XcfInfo      *info,
+           {
+             GimpChannel *mask;
+ 
++            /* We're going to delete *channel, Don't leave its pointer
++             * in @info. See bug #767873.
++             */
++            if (*channel == info->active_channel)
++              info->active_channel = NULL;
++
+             mask =
+               gimp_selection_new (image,
+                                   gimp_item_get_width  (GIMP_ITEM (*channel)),
+@@ -1234,6 +1259,10 @@ xcf_load_channel_props (XcfInfo      *info,
+             *channel = mask;
+             (*channel)->boundary_known = FALSE;
+             (*channel)->bounds_known   = FALSE;
++
++            /* Don't restore info->active_channel because the
++             * selection can't be the active channel
++             */
+           }
+           break;
+ 
+-- 
+cgit v0.12
+
-- 
cgit v1.2.3-65-gdbad