* apt-pkg/pkgcache.cc:

  - Check that cache is at least CacheFileSize bytes large (LP: #16467)

apt-pkg/pkgcache.cc

@@ -157,6 +157,9 @@ bool pkgCache::ReMap(bool const &Errorchecks)
        HeaderP->CheckSizes(DefHeader) == false)
       return _error->Error(_("The package cache file is an incompatible version"));
 
+   if (Map.Size() < HeaderP->CacheFileSize)
+      return _error->Error(_("The package cache file is corrupted, it is too small"));
+
    // Locate our VS..
    if (HeaderP->VerSysName == 0 ||
        (VS = pkgVersioningSystem::GetVS(StrP + HeaderP->VerSysName)) == 0)

debian/changelog

@@ -4,6 +4,8 @@ apt (0.8.16~exp4) UNRELEASED; urgency=low
     - [ABI break] Add pkgCache::Header::CacheFileSize, storing the cache size
   * apt-pkg/pkgcachegen.cc:
     - Write the file size to the cache
+  * apt-pkg/pkgcache.cc:
+    - Check that cache is at least CacheFileSize bytes large (LP: #16467)
 
  -- Julian Andres Klode <jak@debian.org>  Wed, 20 Jul 2011 16:23:55 +0200