From: Sebastian Keller <skeller@gnome.org>
Date: Mon, 3 Feb 2020 00:06:14 +0000 (+0100)
Subject: texture-cache: Fix invalid reads when storing used resource scales
X-Git-Tag: archive/raspbian/50.5-1+rpi1~1^2~781^2^2~17
X-Git-Url: https://dgit.raspbian.org/%22http://www.example.com/cgi/%22/%22http:/www.example.com/cgi/%22?a=commitdiff_plain;h=7287ee365103909c4c3e540a3f7958957f601435;p=gnome-shell.git

texture-cache: Fix invalid reads when storing used resource scales

The used_scales hash table uses g_double_hash and g_double_equal which
try to read a double from the passed pointers. The pointers however were
pointing to a float, leading to an invalid read.

https://gitlab.gnome.org/GNOME/gnome-shell/merge_requests/974
---

diff --git a/src/st/st-texture-cache.c b/src/st/st-texture-cache.c
index 01d193851..7f957bff7 100644
--- a/src/st/st-texture-cache.c
+++ b/src/st/st-texture-cache.c
@@ -1443,8 +1443,9 @@ st_texture_cache_load_file_sync_to_cogl_texture (StTextureCache *cache,
 
       if (policy == ST_TEXTURE_CACHE_POLICY_FOREVER)
         {
+          double resource_scale_double = resource_scale;
           g_hash_table_insert (cache->priv->keyed_cache, g_strdup (key), image);
-          g_hash_table_insert (cache->priv->used_scales, &resource_scale, &resource_scale);
+          g_hash_table_insert (cache->priv->used_scales, &resource_scale_double, &resource_scale_double);
         }
     }
 
@@ -1491,10 +1492,11 @@ st_texture_cache_load_file_sync_to_cairo_surface (StTextureCache        *cache,
 
       if (policy == ST_TEXTURE_CACHE_POLICY_FOREVER)
         {
+          double resource_scale_double = resource_scale;
           cairo_surface_reference (surface);
           g_hash_table_insert (cache->priv->keyed_surface_cache,
                                g_strdup (key), surface);
-          g_hash_table_insert (cache->priv->used_scales, &resource_scale, &resource_scale);
+          g_hash_table_insert (cache->priv->used_scales, &resource_scale_double, &resource_scale_double);
         }
     }
   else