From d3905fcd68b0f754f9d121ecab4630ab968eaf8d Mon Sep 17 00:00:00 2001
From: Cristy <urban-warrior@imagemagick.org>
Date: Sat, 3 Feb 2018 13:16:37 -0500
Subject: [PATCH] ...

---
 MagickCore/blob.c | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/MagickCore/blob.c b/MagickCore/blob.c
index b42415a0f..2bb35466a 100644
--- a/MagickCore/blob.c
+++ b/MagickCore/blob.c
@@ -2713,7 +2713,6 @@ MagickExport MagickBooleanType IsBlobSeekable(const Image *image)
     case BlobStream:
       return(MagickTrue);
     case FileStream:
-    case ZipStream:
     {
       int
         status;
@@ -2723,6 +2722,16 @@ MagickExport MagickBooleanType IsBlobSeekable(const Image *image)
       status=fseek(blob_info->file_info.file,0,SEEK_CUR);
       return(status == -1 ? MagickFalse : MagickTrue);
     }
+    case ZipStream:
+    {
+      int
+        status;
+
+      if (blob_info->file_info.gzfile == (gzFile) NULL)
+        return(MagickFalse);
+      status=gzseek(blob_info->file_info.gzfile,0,SEEK_CUR);
+      return(status == -1 ? MagickFalse : MagickTrue);
+    }
     case UndefinedStream:
     case BZipStream:
     case FifoStream:
-- 
2.40.0