File GraphicsMagick-CVE-2017-15930.patch of Package GraphicsMagick.7893

Index: GraphicsMagick-1.3.25/coders/png.c
===================================================================
--- GraphicsMagick-1.3.25.orig/coders/png.c	2017-11-06 13:01:24.251142530 +0100
+++ GraphicsMagick-1.3.25/coders/png.c	2017-11-06 13:02:15.284022071 +0100
@@ -2837,7 +2837,7 @@ static Image *ReadOneJNGImage(MngInfo *m
     reading_idat,
     status;
 
-  unsigned long
+  size_t
     length;
 
   jng_alpha_compression_method=0;
@@ -2901,7 +2901,7 @@ static Image *ReadOneJNGImage(MngInfo *m
 
       type[0]='\0';
       (void) strcat(type,"errr");
-      length=ReadBlobMSBLong(image);
+      length=(size_t) ReadBlobMSBLong(image);
       count=(unsigned int) ReadBlob(image,4,type);
 
       if (logging)
@@ -3012,6 +3012,30 @@ static Image *ReadOneJNGImage(MngInfo *m
               ThrowReaderException(CorruptImageError,ImproperImageHeader,image);
             }
 
+          /* Rationalize dimensions with blob size if it is available */
+          if (BlobIsSeekable(image))
+            {
+              magick_off_t
+                blob_size;
+
+              blob_size = GetBlobSize(image);
+              if ((blob_size == 0) ||
+                  ((((double) jng_width*jng_height)/blob_size) > 512.0))
+                {
+                  (void) LogMagickEvent(CoderEvent,GetMagickModule(),
+                                        "    Unreasonable dimensions: "
+                                        "geometry = %lux%lu, "
+                                        "blob size = %" MAGICK_OFF_F "d",
+                                        jng_width, jng_height, blob_size);
+
+                  ThrowException(exception,CorruptImageError,
+                                 InsufficientImageDataInFile,image->filename);
+                  MagickFreeMemory(chunk);
+                  DestroyJNGInfo(color_image_info,alpha_image_info);
+                  return ((Image *)NULL);
+                }
+            }
+
           continue;
         }
 
@@ -3363,17 +3387,37 @@ static Image *ReadOneJNGImage(MngInfo *m
                               "    Copying jng_image pixels to main image.");
       image->rows=jng_height;
       image->columns=jng_width;
-      length=image->columns*sizeof(PixelPacket);
+      length=MagickArraySize(image->columns,sizeof(PixelPacket));
+      if (jng_height == 0 || jng_width == 0 || length == 0)
+        {
+          if (logging)
+          (void) LogMagickEvent(CoderEvent,GetMagickModule(),
+              "    jng_width=%lu jng_height=%lu",
+              (unsigned long)jng_width,(unsigned long)jng_height);
+          DestroyJNGInfo(color_image_info, &alpha_image_info);
+          DestroyImage(jng_image);
+          return ((Image *)NULL);
+        }      
       for (y=0; y < (long) image->rows; y++)
         {
           s=AcquireImagePixels(jng_image,0,y,image->columns,1,&image->exception);
           q=SetImagePixels(image,0,y,image->columns,1);
+          if ((s == (const PixelPacket *) NULL) || (q == (PixelPacket *) NULL))
+            break;
           (void) memcpy(q,s,length);
           if (!SyncImagePixels(image))
             break;
         }
       DestroyImage(jng_image);
       jng_image = (Image *)NULL;
+      if ((unsigned long) y != image->rows)
+        {
+          if (logging)
+            (void) LogMagickEvent(CoderEvent,GetMagickModule(),
+                                  "Failed to transfer JPEG scanlines");
+          DestroyJNGInfo(&color_image_info, &alpha_image_info);
+          return ((Image *)NULL);
+        }
       if (alpha_image != (Image *)NULL && !image_info->ping)
         {
           if (jng_color_type >= 12)
@@ -3405,12 +3449,16 @@ static Image *ReadOneJNGImage(MngInfo *m
                   if (image->matte)
                     {
                       q=SetImagePixels(image,0,y,image->columns,1);
+                      if (q == (PixelPacket *) NULL)
+                        break;
                       for (x=(long) image->columns; x > 0; x--,q++,s++)
                         q->opacity=(Quantum) MaxRGB-s->red;
                     }
                   else
                     {
                       q=SetImagePixels(image,0,y,image->columns,1);
+                      if (q == (PixelPacket *) NULL)
+                        break;
                       for (x=(long) image->columns; x > 0; x--,q++,s++)
                         {
                           q->opacity=(Quantum) MaxRGB-s->red;