Fix memory leak with clip device and image width/height = 0

When rendering masked images we can create a clip device in order to do
the actual masking before passing the result to the final device.

After creating the device we store it in a 'gs_image_common_enum' for
later use. We then proceed to initialise the main image enumerator in
gs_image_common_init().

As an optimisation, if the image width or height is 0, we don't waste
any time processing it but simply end the image and exit.

However, if we had created a clip device, we did not free that device
leading to a memory leak.

This commit simply 'un-retains' the device causing it to be freed.

1 files changed, 5 insertions, 0 deletions

diff --git a/base/gsimage.c b/base/gsimage.c
index d62c76eb7..7afea3358 100644
--- a/base/gsimage.c
+++ b/base/gsimage.c
@@ -408,7 +408,12 @@ gs_image_common_init(gs_image_enum * penum, gx_image_enum_common_t * pie,
     int i;
 
     if (pim->Width == 0 || pim->Height == 0) {
+        gx_device *cdev = pie->dev;
+
         gx_image_end(pie, false);
+        if (dev_proc(cdev, dev_spec_op)(cdev,
+                    gxdso_pattern_is_cpath_accum, NULL, 0))
+            gx_device_retain((gx_device *)cdev, false);
         return 1;
     }
     image_enum_init(penum);