https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=6203

diff --git a/coders/dib.c b/coders/dib.c
index 22941fe237a065a4aae50001f113d50d0f215c4b..05f50bca139ab8815db2752033e206f8151f78be 100644 (file)
--- a/coders/dib.c
+++ b/coders/dib.c
@@ -576,8 +576,8 @@ static Image *ReadDIBImage(const ImageInfo *image_info,ExceptionInfo *exception)
     default:
       ThrowReaderException(CorruptImageError,"UnrecognizedImageCompression");
   }
-  image->columns=(size_t) MagickAbsoluteValue(dib_info.width);
-  image->rows=(size_t) MagickAbsoluteValue(dib_info.height);
+  image->columns=(size_t) MagickAbsoluteValue((ssize_t) dib_info.width);
+  image->rows=(size_t) MagickAbsoluteValue((ssize_t) dib_info.height);
   image->depth=8;
   image->alpha_trait=dib_info.bits_per_pixel == 32 ? BlendPixelTrait :
     UndefinedPixelTrait;