Merge pull request #2059 from ynse01/issue-exif-null-array-value

Fix null reference exception on Exif clone of null ExifArrayValue

src/ImageSharp/Metadata/Profiles/Exif/Values/ExifValue.cs

@@ -29,7 +29,7 @@ namespace SixLabors.ImageSharp.Metadata.Profiles.Exif
             {
                 // All array types are value types so Clone() is sufficient here.
                 var array = (Array)other.GetValue();
-                this.TrySetValue(array.Clone());
+                this.TrySetValue(array?.Clone());
             }
         }
 

tests/ImageSharp.Tests/Formats/Jpg/JpegDecoderTests.Metadata.cs

@@ -302,6 +302,19 @@ namespace SixLabors.ImageSharp.Tests.Formats.Jpg
             Assert.Null(ex);
         }
 
+        [Theory]
+        [WithFile(TestImages.Jpeg.Issues.ExifNullArrayTag, PixelTypes.Rgba32)]
+        public void Clone_WithNullRationalArrayTag_DoesNotThrowException<TPixel>(TestImageProvider<TPixel> provider)
+            where TPixel : unmanaged, IPixel<TPixel>
+        {
+            Exception ex = Record.Exception(() =>
+            {
+                using Image<TPixel> image = provider.GetImage(JpegDecoder);
+                var clone = image.Metadata.ExifProfile.DeepClone();
+            });
+            Assert.Null(ex);
+        }
+
         [Fact]
         public void EncodedStringTags_WriteAndRead()
         {

tests/ImageSharp.Tests/TestImages.cs

@@ -262,6 +262,7 @@ namespace SixLabors.ImageSharp.Tests
                 public const string MalformedUnsupportedComponentCount = "Jpg/issues/issue-1900-malformed-unsupported-255-components.jpg";
                 public const string MultipleApp01932 = "Jpg/issues/issue-1932-app0-resolution.jpg";
                 public const string InvalidIptcTag = "Jpg/issues/Issue1942InvalidIptcTag.jpg";
+                public const string ExifNullArrayTag = "Jpg/issues/issue-2056-exif-null-array.jpg";
 
                 public static class Fuzz
                 {

tests/Images/Input/Jpg/issues/issue-2056-exif-null-array.jpg

@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:4c52500be37a8ea1ee1caeb78c79e44b02e10912df4f6db65313c6745573c8ee
+size 250451