From: Jehan <jehan@girinstud.io>
Date: Wed, 20 Dec 2017 16:44:20 +0100
Subject: Bug 790849 - (CVE-2017-17789) CVE-2017-17789 Heap buffer overflow...
Origin: https://git.gnome.org/browse/GIMP/commit/?id=01898f10f87a094665a7fdcf7153990f4e511d3f
Bug-Debian-Security: https://security-tracker.debian.org/tracker/CVE-2017-17789
Bug-Debian: https://bugs.debian.org/884837
Bug: https://bugzilla.gnome.org/show_bug.cgi?id=790849

... in PSP importer.
Check if declared block length is valid (i.e. within the actual file)
before going further.
Consider the file as broken otherwise and fail loading it.

(cherry picked from commit 28e95fbeb5720e6005a088fa811f5bf3c1af48b8)
---
 plug-ins/common/file-psp.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/plug-ins/common/file-psp.c b/plug-ins/common/file-psp.c
index ac0fff78f0..4cbafe37b1 100644
--- a/plug-ins/common/file-psp.c
+++ b/plug-ins/common/file-psp.c
@@ -1771,6 +1771,15 @@ load_image (const gchar  *filename,
     {
       block_start = ftell (f);
 
+      if (block_start + block_total_len > st.st_size)
+        {
+          g_set_error (error, G_FILE_ERROR, G_FILE_ERROR_FAILED,
+                       _("Could not open '%s' for reading: %s"),
+                       gimp_filename_to_utf8 (filename),
+                       _("invalid block size"));
+          goto error;
+        }
+
       if (id == PSP_IMAGE_BLOCK)
         {
           if (block_number != 0)
-- 
2.15.1