diff --git a/libtiff/tif_dirread.c b/libtiff/tif_dirread.c
index e9fe5c35..ba127ca9 100644
--- a/libtiff/tif_dirread.c
+++ b/libtiff/tif_dirread.c
@@ -838,6 +838,7 @@ static enum TIFFReadDirEntryErr TIFFReadDirEntryArrayWithLimit(
 	uint32 datasize;
 	void* data;
         uint64 target_count64;
+        int original_datasize_clamped;
 	typesize=TIFFDataWidth(direntry->tdir_type);
 
         target_count64 = (direntry->tdir_count > maxcount) ?
@@ -850,6 +851,12 @@ static enum TIFFReadDirEntryErr TIFFReadDirEntryArrayWithLimit(
 	}
         (void) desttypesize;
 
+        /* We just want to know if the original tag size is more than 4 bytes
+         * (classic TIFF) or 8 bytes (BigTIFF)
+         */
+        original_datasize_clamped =
+            ((direntry->tdir_count > 10) ? 10 : (int)direntry->tdir_count) * typesize;
+
         /* 
          * As a sanity check, make sure we have no more than a 2GB tag array 
          * in either the current data type or the dest data type.  This also
@@ -881,7 +888,7 @@ static enum TIFFReadDirEntryErr TIFFReadDirEntryArrayWithLimit(
 	}
 	if (!(tif->tif_flags&TIFF_BIGTIFF))
 	{
-		if (datasize<=4)
+		if (original_datasize_clamped<=4)
 			_TIFFmemcpy(data,&direntry->tdir_offset,datasize);
 		else
 		{
@@ -902,7 +909,7 @@ static enum TIFFReadDirEntryErr TIFFReadDirEntryArrayWithLimit(
 	}
 	else
 	{
-		if (datasize<=8)
+		if (original_datasize_clamped<=8)
 			_TIFFmemcpy(data,&direntry->tdir_offset,datasize);
 		else
 		{