(gif_load): Fix size of allocated image buffer

for images where a sub-image may be larger than the image's
total height/width specifications.

1 files changed, 11 insertions, 7 deletions

diff --git a/src/image.c b/src/image.c
index 6ec0734e785..bdc78c2d718 100644
--- a/src/image.c
+++ b/src/image.c
@@ -7369,8 +7369,17 @@ gif_load (f, img)
       return 0;
     }
 
-  width = img->width = max (gif->SWidth, gif->Image.Left + gif->Image.Width);
-  height = img->height = max (gif->SHeight, gif->Image.Top + gif->Image.Height);
+  image_top = gif->SavedImages[ino].ImageDesc.Top;
+  image_left = gif->SavedImages[ino].ImageDesc.Left;
+  image_width = gif->SavedImages[ino].ImageDesc.Width;
+  image_height = gif->SavedImages[ino].ImageDesc.Height;
+
+  width = img->width = max (gif->SWidth,
+                            max (gif->Image.Left + gif->Image.Width,
+                                 image_left + image_width));
+  height = img->height = max (gif->SHeight,
+                              max (gif->Image.Top + gif->Image.Height,
+                                   image_top + image_height));
 
   /* Create the X image and pixmap.  */
   if (!x_create_x_image_and_pixmap (f, width, height, 0, &ximg, &img->pixmap))
@@ -7405,11 +7414,6 @@ gif_load (f, img)
      requires more than can be done here (see the gif89 spec,
      disposal methods).  Let's simply assume that the part
      not covered by a sub-image is in the frame's background color.  */
-  image_top = gif->SavedImages[ino].ImageDesc.Top;
-  image_left = gif->SavedImages[ino].ImageDesc.Left;
-  image_width = gif->SavedImages[ino].ImageDesc.Width;
-  image_height = gif->SavedImages[ino].ImageDesc.Height;
-
   for (y = 0; y < image_top; ++y)
     for (x = 0; x < width; ++x)
       XPutPixel (ximg, x, y, FRAME_BACKGROUND_PIXEL (f));