diff options
Diffstat (limited to 'media-gfx/gimp/files/gimp-2.9.2-CVE-2016-4994.patch')
-rw-r--r-- | media-gfx/gimp/files/gimp-2.9.2-CVE-2016-4994.patch | 88 |
1 files changed, 88 insertions, 0 deletions
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 + |